In astronomy, first light is the first time a telescope is used to look at the Universe. This is often not the first time the telescope has been used. Tests will have been done during daylight to make sure everything is working. Images taken during first light are not normally of scientific interest. They are usually poor quality as the parts of the telescope have not been properly adjusted for best performance. Usually, a well-known and spectacular astronomical object is chosen. First light is always a moment of great excitement, both for the people who designed and built the telescope, and for the astronomical community.

For example, the 200-inch Hale Telescope saw first light January 26, 1949, targeting a nebula located in the constellation Monoceros. under the direction of American astronomer Edwin Hubble. The image was published in many magazines.

The Large Binocular Telescope had its first light with a single primary mirror on October 12, 2005. This was a view of NGC 891, a spiral galaxy in the Andromeda constellation . The second mirror was installed in January 2006 and the telescope became fully operational in January 2008.

In physical cosmology, first light refers to the light coming from the first generation of hyperstars. These were formed less than a billion years after the big bang, bringing an end to the cosmological Dark Ages.

References

Telescopes

First light (astronomy)


Istrianis crauropa is a moth of the family Gelechiidae. It is found in southern India.

The wingspan is about 6 mm. The forewings are dark grey, sprinkled whitish and with undefined elongate spots of blackish irroration on the costa at one-fifth, two-fifths, and three-fifths, separated and last followed by small suffused whitish spots. There is a black subbasal dot on the dorsum surrounded by ochreous-brownish suffusion and there is an oblique black bar in the disc at one-fourth, surrounded by ochreous-brown. Several ochreous-brown tufts are found in the disc and there is some irregular ochreous-brown suffusion, as well as small blackish dots posteriorly. The hindwings are pale grey.

The larvae feed on the leaves of Butea frondosa. Pupation takes place in a spindle shaped cocoon made on the leaf.

References

Moths described in 1918
Istrianis

Istrianis crauropa


Eugênio Bucci (Orlândia) is a Brazilian journalist, known for his works at many Brazilian publications and also for his time as president of Radiobras (now working under the name Agência Brasil).

Biography

Bucci graduated in Social Communication at Communication and Arts School of the University of São Paulo (ECA-USP) in 1982 and in Law at the same university.

In 1984, he was president of the Centro Acadêmico XI de Agosto, from USP. His campaign group was called "The Pravda", in allusion of the American newspaper The New York Times and the official soviet publication Pravda. The same group elected his successor, Fernando Haddad. Affiliated to the Worker's Party in the early 80s, he was the creator and first editor of the magazine Teoria e Debate, published by Fundação Perseu Abramo.

As a journalist, he was director of magazines such as Set, Superinteressante, Playboy and Quatro Rodas, culture and television critic in newspapers like (Folha de S.Paulo, O Estado de S. Paulo, Jornal do Brasil) and magazines as (Veja, Nova Escola and Sem Fronteiras), besides being Editorial Secretary of Editora Abril.

In 2002, he became doctor at Communication Science, Journalism area, at ECA-USP. He taught journalistic ethics at Faculdade Cásper Líbero in 2001 and 2002.

From January 2003 to April 2007, he directed Radiobrás (Empresa Brasileira de Comunicação S.A), leading the process of revitalization and repositioning of the company. His work was positively received by the press, the critics and other politicians and intellectuals, granting him national and international prizes.

After leaving the position at Radiobras, he became Visiting Professor at the Advanced Studies Institute of University of São Paulo. Currently, he is a member of the Curator Council of the Fundação Padre Anchieta, he works occasionally for O Estado de S. Paulo and with the website Observatório da Imprensa. In 2008, he became a professor at ECA-USP. In the same year, he became ombudsman of the "Jornal do Campus", a newspaper edited by the students from the second grade of the Journalist course of the university. In 2010, he became director of the new post-graduation course of journalism at ESPM, although he still works at USP.

Bucci has published many books, including a partnership with Maria Rita Kehl.

Bibliography
2009: "A Imprensa e o Dever da Liberdade", Editora Contexto.
2008: "Em Brasília, 19 horas: a Guerra entre a Chapa-branca e o Direito à Informação no Primeiro Governo Lula", Editora Record.
2006: "Jornalismo Sitiado" (livro + DVD, com Sidnei Basile), estúdio Log On / Culturamarcas.
2004: "Videologias" (co-autora Maria Rita Kehl), Editora Boitempo.
2003: "Do B: Críticas para o Caderno B do Jornal do Brasil".
2001: "Sobre ética e imprensa", ed. Companhia das Letras.
2000: "A TV aos 50" (org.), Fundação Perseu Abramo.
1997: "Brasil em Tempo de TV", Editora Boitempo.
1993: "O Peixe Morre pela Boca: oito Artigos sobre Cultura e Poder", Scritta Editorial.
1982: "Um Balde" (compilation of poetry in collaboration with Guian de Bastos and Gomes Moor), edited by Masao Ohno.

Articles published in collective books
2007: "Comunicação pública: Estado, Mercado, Sociedade e Interesse Público" (org. Jorge Duarte), Editora Atlas.
2004: "Educação, Cidadania e Direitos Humanos" (org. José Sérgio Fonseca de Carvalho), Editora Vozes.
2002: "Comunicação na Pólis: Ensaios sobre Mídia e Política" (org. Clóvis de Barros Filho), Editora Vozes.
1996: "Libertinos, Libertários"; (org. Adauto Novaes), Companhia das Letras.
1993: "Diário da Viagem ao Brasil Esquecido", Scritta Editorial.
1992: "O Cinema dos Anos 80"; (org. Amir Labaki), Editora Brasiliense.

References

1958 births
Living people
People from Orlândia
Brazilian people of Italian descent
Brazilian journalists
Brazilian male journalists
Brazilian non-fiction writers
University of São Paulo alumni
Academic staff of the University of São Paulo

Eugênio Bucci


A recession is where there is a long period of time where there is economic decline. This can mean that people are choosing not to spend their money (due to Deflation) or are choosing to rapidly convert their money (due to Inflation).

An example of this is the Great Recession of 2007-2008.

References

Economics

Recession


Oggar, the World's Mightiest Immortal, is a fictional character from the publisher Fawcett Comics, whose publication rights were acquired by DC Comics in the 1970s. Oggar was a villain of Captain Marvel chronology in Pre-Crisis; he made no Post-Crisis appearances. He first appeared in Captain Marvel Adventures # 61 (May 1946, Fawcett Comics). His first appearance in DC Comics was in World's Finest Comics # 264 (August 1980).

He was a major recurring enemy of the Marvels in the DC Comics stories published before the continuity-resetting Crisis on Infinite Earths miniseries in 1985.

Development
In a 1974 interview, writer Otto Binder admitted, "The Oggar serial was really a flop, to be frank. It was again one of my ideas and it seemed to be great in my mind, but when it came to writing and developing the theme, it just sort of went nowhere and it was quickly killed after six chapters. That was how it worked: For every good idea, there were a couple of so-so ones."

Fictional character biography
Originally, the Wizard Shazam was called Shazamo. He was a powerful wizard and led a pantheon of heroes whose initials formed its name: Solomon, Hercules, Atlas, Zeus, Achilles, Mercury ... and Oggar. However, power corrupted Oggar, who was a former pupil of Shazamo. At one point, Oggar refused an order from Shazamo to help a small nation that was being invaded by a tyrant. Oggar stated that Shazamo was getting old and that Oggar himself should lead the pantheon. After engaging in combat with Shazamo, he could not counter the wizard's power. Shazamo consequently condemned Oggar to live among mortals and subsequently removed the "O" from his name. Before leaving, Oggar remained close enough to the gates of the Shazamo temple that he heard a prophecy: In the twentieth century, the wizard (now Shazam) would die and would have a successor named Billy Batson. Billy was destined to become Captain Marvel and acquire the combined powers of the remaining heroes of the pantheon. Oggar thought it would be wise to wait until the twentieth century when there would only be Captain Marvel rather than seven enemies to defeat. However, 3000 years ago in the mortal world, Oggar tried to seduce the beautiful Circe to be his queen while attempting to conquer the world, but she refused (Note: This is Earth-S Circe; yet she resembles the mythological figure but is not the same Circe from the actual DC Universe). Oggar tried to avenge himself, but his magic was unable to harm women. So instead he gave her a gift by making her immortal. However, the spell did nothing to mitigate the effects of aging and after about 200 years she was still alive but terribly ugly and wrinkled. She eventually developed a mortal hatred of all men who were now horrified by her face. She learned witchcraft and how to turn men into animals. After his rebellion, the wizard Shazam cursed Oggar with cloven hooves.

Oggar returned in the twentieth century and battled Captain Marvel as he tried to recruit people to the Cult of the Curse. If they left, they were driven mad. However, he finally encountered Circe, who turned him into a boar. In this form, he fell off of a precipice and died.

However, he was able to reform himself with his magic due to the help of Mr. Mind and joined the Monster Society of Evil. He and Black Adam went to conquer Egypt. With his magic he turned Billy mute, then summoned up an army from the sand for Black Adam to lead. However Mary Marvel was able to trick him into striking Billy with lightning, after which the two Marvels defeat the army. Oggar and the rest of the Society attack the Rock of Eternity, forcing the entire Marvel Family to fight them. Mary disguises herself as her brother and gets close enough to Oggar to bind and gag him.

Powers and abilities
Oggar has divine strength and durability equal to Captain Marvel's. He possesses vast magical powers that enable him to do nearly anything, like fly, create objects, teleport himself and others, make people burst into flames, create a large fissure in the ground, create an invisible, indestructible force field, mute people, shoot lightning bolts out of his finger, or summon a magic lightning bolt to change Captain Marvel back into Billy Batson, although each spell could only be used once against the same person.

Oggar's power cannot be used to directly harm a female target, which makes Mary Marvel the preferred member of the Marvel Family to deal with him (however, Oggar has repeatedly worked around this limitation; one time by giving immortality to Circe without giving her eternal youth, and another time by directing magical lightning to strike the ground where Mary Marvel was standing).

By kicking someone in their forehead with one of his cloven hooves, Oggar can brand them with the mark of his cult of the curse: a hoof print on their forehead. The person then must obey Oggar's every command, or the hoof print vanishes and they become struck by a curse that turns them insane. However, if the person is already insane, the curse cures their insanity instead. Oggar is also immortal, and cannot age. However, he is vulnerable to magical transformation spells.

References

Characters created by Bill Parker (comics)
Characters created by C. C. Beck
Characters created by Otto Binder
Comics characters introduced in 1946
DC Comics characters with superhuman durability or invulnerability
DC Comics characters with superhuman strength
DC Comics supervillains
Fawcett Comics supervillains
DC Comics characters who use magic
DC Comics characters who can teleport
Golden Age supervillains
Fictional characters with immortality
Fictional characters with electric or magnetic abilities
Fictional characters with fire or heat abilities
Captain Marvel (DC Comics)

Oggar


St Miliau or Miliav is a Breton saint and eponym of the village of Guimiliau, where he is particularly venerated.  He is said to be a good saint to invoke in cases of rheumatism. St Miliau is a figure of some importance in Breton cult and legend. He is sometimes represented as a cephalophore, i.e. holding his own severed head. It is hard to be sure what historical core there might be to the legends.

Legend
The legend of St Miliau, as retold in Brittany, pictures him as a good and just prince, slain by his evil brother. Miliau was the son of Budic and grandson of Alain le Long, kings of Armorica in Brittany. His brothers were Theodoric and Rivod. Miliau is said to have married Haurille and their son was St Melar. Miliau was famous as a protector and benefactor of the poor, and is represented as dividing his cloak with a beggar, like St Martin of Tours. When he succeeded to the throne, Rivod had him assassinated by decapitation, around 531. A few years later, Rivod eliminated Melar in the same way.

However, the historical Alan I, King of Brittany, flourished in the 9th century and died in 907. He really did have a son called Budic, who did not succeed him as king. The date 892 is sometimes given for the martyrdom of St Miliau, making him a contemporary of the Carolingian emperors, rather than the early Merovingian kings. This seems a better fit with the alleged ancestry of St Miliau, and it is reasonable to suppose that Budic might have had two sons who quarreled over their ranking within the kingdom. This dating separates Miliau from St Melar by more than three centuries. On the other hand, the paternity, and even the geographical origins, of Melar are disputed, and it possible that the connection between the two is based on a misunderstanding.

A further confusing factor is that St Hervé, whose date of death (as an old man) is generally given as 556, is also regarded as a native of Guimiliau. Even the earlier dating for Miliau would make it improbable that Hervé was born in a village of that name, though it would not exclude the possibility that he was born in that locality some time before Miliau.

References

Medieval Breton saints
Cephalophores
6th-century Christian saints

Miliau


In mathematics, a Clifford algebra is an algebra generated by a vector space with a quadratic form, and is a unital associative algebra. As -algebras, they generalize the real numbers, complex numbers, quaternions and several other hypercomplex number systems. The theory of Clifford algebras is intimately connected with the theory of quadratic forms and orthogonal transformations. Clifford algebras have important applications in a variety of fields including geometry, theoretical physics and digital image processing. They are named after the English mathematician William Kingdon Clifford (1845–1879).

The most familiar Clifford algebras, the orthogonal Clifford algebras, are also referred to as (pseudo-)Riemannian Clifford algebras, as distinct from symplectic Clifford algebras.

Introduction and basic properties
A Clifford algebra is a unital associative algebra that contains and is generated by a vector space  over a field , where  is equipped with a quadratic form . The Clifford algebra  is the "freest" unital associative algebra generated by  subject to the condition

where the product on the left is that of the algebra, and the  is its multiplicative identity.  The idea of being the "freest" or "most general" algebra subject to this identity can be formally expressed through the notion of a universal property, as done below.

When  is a finite-dimensional real vector space and  is nondegenerate,  may be identified by the label , indicating that  has an orthogonal basis with  elements with ,  with , and where  indicates that this is a Clifford algebra over the reals; i.e. coefficients of elements of the algebra are real numbers. This basis may be found by orthogonal diagonalization.

The free algebra generated by  may be written as the tensor algebra , that is, the direct sum of the tensor product of  copies of  over all . Therefore one obtains a Clifford algebra as the quotient of this tensor algebra by the two-sided ideal generated by elements of the form  for all elements . The product induced by the tensor product in the quotient algebra is written using juxtaposition (e.g. ).  Its associativity follows from the associativity of the tensor product.

The Clifford algebra has a distinguished subspace , being the image of the embedding map. Such a subspace cannot in general be uniquely determined given only a -algebra isomorphic to the Clifford algebra.

If the characteristic of the ground field  is not , then one can rewrite the fundamental identity above in the form

where

is the symmetric bilinear form associated with , via the polarization identity.

Quadratic forms and Clifford algebras in characteristic  form an exceptional case. In particular, if  it is not true that a quadratic form uniquely determines a symmetric bilinear form satisfying , nor that every quadratic form admits an orthogonal basis. Many of the statements in this article include the condition that the characteristic is not , and are false if this condition is removed.

As a quantization of the exterior algebra
Clifford algebras are closely related to exterior algebras. Indeed, if  then the Clifford algebra  is just the exterior algebra . For nonzero  there exists a canonical linear isomorphism between  and  whenever the ground field  does not have characteristic two. That is, they are naturally isomorphic as vector spaces, but with different multiplications (in the case of characteristic two, they are still isomorphic as vector spaces, just not naturally). Clifford multiplication together with the distinguished subspace is strictly richer than the exterior product since it makes use of the extra information provided by .

The Clifford algebra is a filtered algebra, the associated graded algebra is the exterior algebra.

More precisely, Clifford algebras may be thought of as quantizations (cf. quantum group) of the exterior algebra, in the same way that the Weyl algebra is a quantization of the symmetric algebra.

Weyl algebras and Clifford algebras admit a further structure of a *-algebra, and can be unified as even and odd terms of a superalgebra, as discussed in CCR and CAR algebras.

Universal property and construction
Let  be a vector space over a field , and let  be a quadratic form on .  In most cases of interest the field  is either the field of real numbers , or the field of complex numbers , or a finite field.

A Clifford algebra  is a pair , where  is a unital associative algebra over  and  is a linear map  satisfying  for all  in , defined by the following universal property: given any unital associative algebra  over  and any linear map  such that

(where  denotes the multiplicative identity of ), there is a unique algebra homomorphism  such that the following diagram commutes (i.e. such that ):

The quadratic form  may be replaced by a (not necessarily symmetric) bilinear form  that has the property , in which case an equivalent requirement on  is

When the characteristic of the field is not , this may be replaced by what is then an equivalent requirement,

where the bilinear form may additionally be restricted to being symmetric without loss of generality.

A Clifford algebra as described above always exists and can be constructed as follows: start with the most general algebra that contains , namely the tensor algebra , and then enforce the fundamental identity by taking a suitable quotient. In our case we want to take the two-sided ideal  in  generated by all elements of the form
 for all
and define  as the quotient algebra

The ring product inherited by this quotient is sometimes referred to as the Clifford product to distinguish it from the exterior product and the scalar product.

It is then straightforward to show that  contains  and satisfies the above universal property, so that  is unique up to a unique isomorphism; thus one speaks of "the" Clifford algebra . It also follows from this construction that  is injective. One usually drops the  and considers  as a linear subspace of .

The universal characterization of the Clifford algebra shows that the construction of  is  in nature. Namely,  can be considered as a functor from the category of vector spaces with quadratic forms (whose morphisms are linear maps preserving the quadratic form) to the category of associative algebras. The universal property guarantees that linear maps between vector spaces (preserving the quadratic form) extend uniquely to algebra homomorphisms between the associated Clifford algebras.

Basis and dimension

Since  comes equipped with a quadratic form , in characteristic not equal to  there exist bases for  that are orthogonal. An orthogonal basis is one such that for a symmetric bilinear form
 for , and

The fundamental Clifford identity implies that for an orthogonal basis
 for , and

This makes manipulation of orthogonal basis vectors quite simple. Given a product  of distinct orthogonal basis vectors of , one can put them into a standard order while including an overall sign determined by the number of pairwise swaps needed to do so (i.e. the signature of the ordering permutation).

If the dimension of  over  is  and  is an orthogonal basis of , then  is free over  with a basis

The empty product () is defined as the multiplicative identity element. For each value of  there are  basis elements, so the total dimension of the Clifford algebra is

Examples: real and complex Clifford algebras
The most important Clifford algebras are those over real and complex vector spaces equipped with nondegenerate quadratic forms.

Each of the algebras  and  is isomorphic to  or , where  is a full matrix ring with entries from , , or . For a complete classification of these algebras see Classification of Clifford algebras.

Real numbers

Clifford algebras are also sometimes referred to as geometric algebras, most often over the real numbers.

Every nondegenerate quadratic form on a finite-dimensional real vector space is equivalent to the standard diagonal form:

where  is the dimension of the vector space. The pair of integers  is called the signature of the quadratic form. The real vector space with this quadratic form is often denoted  The Clifford algebra on  is denoted   The symbol   means either  or  depending on whether the author prefers positive-definite or negative-definite spaces.

A standard basis  for  consists of  mutually orthogonal vectors,  of which square to  and  of which square to . Of such a basis, the algebra  will therefore have  vectors that square to  and  vectors that square to .

A few low-dimensional cases are:
  is naturally isomorphic to  since there are no nonzero vectors.
  is a two-dimensional algebra generated by  that squares to −1, and is algebra-isomorphic to , the field of complex numbers.
  is a four-dimensional algebra spanned by  The latter three elements all square to  and anticommute, and so the algebra is isomorphic to the quaternions .
  is an 8-dimensional algebra isomorphic to the direct sum , the split-biquaternions.

Complex numbers
One can also study Clifford algebras on complex vector spaces. Every nondegenerate quadratic form on a complex vector space of dimension n is equivalent to the standard diagonal form

Thus, for each dimension , up to isomorphism there is only one Clifford algebra of a complex vector space with a nondegenerate quadratic form. We will denote the Clifford algebra on  with the standard quadratic form by .

For the first few cases one finds that
 , the complex numbers
 , the bicomplex numbers
 , the biquaternions
where  denotes the algebra of  matrices over .

Examples: constructing quaternions and dual quaternions

Quaternions
In this section, Hamilton's quaternions are constructed as the even subalgebra of the Clifford algebra .

Let the vector space  be real three-dimensional space , and the quadratic form be the usual quadratic form.  Then, for  in  we have the bilinear form (or scalar product)

Now introduce the Clifford product of vectors  and  given by

Denote a set of orthogonal unit vectors of  as , then the Clifford product yields the relations

and

The general element of the Clifford algebra  is given by

The linear combination of the even degree elements of  defines the even subalgebra  with the general element

The basis elements can be identified with the quaternion basis elements  as

which shows that the even subalgebra  is Hamilton's real quaternion algebra.

To see this, compute

and

Finally,

Dual quaternions
In this section, dual quaternions are constructed as the even Clifford algebra of real four-dimensional space with a degenerate quadratic form.

Let the vector space  be real four-dimensional space  and let the quadratic form  be a degenerate form derived from the Euclidean metric on   For  in  introduce the degenerate bilinear form

This degenerate scalar product projects distance measurements in  onto the  hyperplane.

The Clifford product of vectors  and  is given by

Note the negative sign is introduced to simplify the correspondence with quaternions.

Denote a set of mutually orthogonal unit vectors of  as  then the Clifford product yields the relations

and

The general element of the Clifford algebra  has 16 components.  The linear combination of the even degree elements defines the even subalgebra  with the general element

The basis elements can be identified with the quaternion basis elements  and the dual unit  as

This provides the correspondence of  with dual quaternion algebra.

To see this, compute

and

The exchanges of  and  alternate signs an even number of times, and show the dual unit  commutes with the quaternion basis elements

Examples: in small dimension
Let  be any field of characteristic not .

Dimension 1
For , if  has diagonalization , that is there is a non-zero vector  such that , then  is algebra-isomorphic to a -algebra generated by an element  satisfying , the quadratic algebra .

In particular, if  (that is,  is the zero quadratic form) then  is algebra-isomorphic to the dual numbers algebra over .

If  is a non-zero square in , then .

Otherwise,  is isomorphic to the quadratic field extension  of .

Dimension 2
For , if  has diagonalization  with non-zero  and  (which always exists if  is non-degenerate), then  is isomorphic to a -algebra generated by elements  and  satisfying ,  and .

Thus  is isomorphic to the (generalized) quaternion algebra . We retrieve Hamilton's quaternions when , since .

As a special case, if some  in  satisfies , then .

Properties

Relation to the exterior algebra
Given a vector space , one can construct the exterior algebra , whose definition is independent of any quadratic form on . It turns out that if  does not have characteristic  then there is a natural isomorphism between  and  considered as vector spaces (and there exists an isomorphism in characteristic two, which may not be natural). This is an algebra isomorphism if and only if . One can thus consider the Clifford algebra  as an enrichment (or more precisely, a quantization, cf. the Introduction) of the exterior algebra on  with a multiplication that depends on  (one can still define the exterior product independently of ).

The easiest way to establish the isomorphism is to choose an orthogonal basis  for  and extend it to a basis for  as described above. The map  is determined by

Note that this only works if the basis  is orthogonal. One can show that this map is independent of the choice of orthogonal basis and so gives a natural isomorphism.

If the characteristic of  is , one can also establish the isomorphism by antisymmetrizing. Define functions  by

where the sum is taken over the symmetric group on  elements, . Since  is alternating it induces a unique linear map . The direct sum of these maps gives a linear map between  and . This map can be shown to be a linear isomorphism, and it is natural.

A more sophisticated way to view the relationship is to construct a filtration on . Recall that the tensor algebra  has a natural filtration: , where  contains sums of tensors with order . Projecting this down to the Clifford algebra gives a filtration on . The associated graded algebra

is naturally isomorphic to the exterior algebra .  Since the associated graded algebra of a filtered algebra is always isomorphic to the filtered algebra as filtered vector spaces (by choosing complements of  in  for all ), this provides an isomorphism (although not a natural one) in any characteristic, even two.

Grading
In the following, assume that the characteristic is not .

Clifford algebras are -graded algebras (also known as superalgebras).  Indeed, the linear map on V defined by  (reflection through the origin) preserves the quadratic form Q and so by the universal property of Clifford algebras extends to an algebra automorphism

Since  is an involution (i.e. it squares to the identity) one can decompose  into positive and negative eigenspaces of

where

Since  is an automorphism it follows that:

where the bracketed superscripts are read modulo 2. This gives  the structure of a -graded algebra.  The subspace  forms a subalgebra of , called the even subalgebra. The subspace  is called the odd part of  (it is not a subalgebra).  -grading plays an important role in the analysis and application of Clifford algebras. The automorphism  is called the main involution or grade involution. Elements that are pure in this -grading are simply said to be even or odd.

Remark. The Clifford algebra is not a  -graded algebra, but is -filtered, where  is the subspace spanned by all products of at most  elements of .

The degree of a Clifford number usually refers to the degree in the -grading.

The even subalgebra  of a Clifford algebra is itself isomorphic to a Clifford algebra. If  is the orthogonal direct sum of a vector  of nonzero norm  and a subspace , then  is isomorphic to , where  is the form  restricted to  and multiplied by . In particular over the reals this implies that:

In the negative-definite case this gives an inclusion , which extends the sequence

Likewise, in the complex case, one can show that the even subalgebra of  is isomorphic to .

Antiautomorphisms
In addition to the automorphism , there are two antiautomorphisms that play an important role in the analysis of Clifford algebras. Recall that the tensor algebra  comes with an antiautomorphism that reverses the order in all products of vectors:

Since the ideal  is invariant under this reversal, this operation descends to an antiautomorphism of  called the transpose or reversal operation, denoted by . The transpose is an antiautomorphism: . The transpose operation makes no use of the -grading so we define a second antiautomorphism by composing  and the transpose. We call this operation Clifford conjugation denoted

Of the two antiautomorphisms, the transpose is the more fundamental.

Note that all of these operations are involutions. One can show that they act as  on elements which are pure in the -grading. In fact, all three operations depend only on the degree modulo . That is, if  is pure with degree  then

where the signs are given by the following table:

Clifford scalar product
When the characteristic is not , the quadratic form  on  can be extended to a quadratic form on all of  (which we also denoted by ). A basis-independent definition of one such extension is

where  denotes the scalar part of  (the degree- part in the -grading). One can show that

where the  are elements of  – this identity is not true for arbitrary elements of .

The associated symmetric bilinear form on  is given by

One can check that this reduces to the original bilinear form when restricted to . The bilinear form on all of  is nondegenerate if and only if it is nondegenerate on .

The operator of left (respectively right) Clifford multiplication by the transpose  of an element  is the adjoint of left (respectively right) Clifford multiplication by  with respect to this inner product. That is,

and

Structure of Clifford algebras
In this section we assume that characteristic is not , the vector space  is finite-dimensional and that the associated symmetric bilinear form of  is nondegenerate.

A central simple algebra over  is a matrix algebra over a (finite-dimensional) division algebra with center . For example, the central simple algebras over the reals are matrix algebras over either the reals or the quaternions.
 If  has even dimension then  is a central simple algebra over .
 If  has even dimension then the even subalgebra  is a central simple algebra over a quadratic extension of  or a sum of two isomorphic central simple algebras over .
 If  has odd dimension then  is a central simple algebra over a quadratic extension of  or a sum of two isomorphic central simple algebras over .
 If  has odd dimension then the even subalgebra  is a central simple algebra over .

The structure of Clifford algebras can be worked out explicitly using the following result. Suppose that  has even dimension and a non-singular bilinear form with discriminant , and suppose that  is another vector space with a quadratic form. The Clifford algebra of  is isomorphic to the tensor product of the Clifford algebras of  and , which is the space  with its quadratic form multiplied by . Over the reals, this implies in particular that

These formulas can be used to find the structure of all real Clifford algebras and all complex Clifford algebras;  see the classification of Clifford algebras.

Notably, the Morita equivalence class of a Clifford algebra (its representation theory: the equivalence class of the category of modules over it) depends only on the signature . This is an algebraic form of Bott periodicity.

Lipschitz group
The class of Lipschitz groups ( Clifford groups or Clifford–Lipschitz groups) was discovered by Rudolf Lipschitz.

In this section we assume that  is finite-dimensional and the quadratic form  is nondegenerate.

An action on the elements of a Clifford algebra by its group of units may be defined in terms of a twisted conjugation: twisted conjugation by  maps , where  is the main involution defined above.

The Lipschitz group  is defined to be the set of invertible elements  that stabilize the set of vectors under this action, meaning that for all   in  we have:

This formula also defines an action of the Lipschitz group on the vector space  that preserves the quadratic form , and so gives a homomorphism from the Lipschitz group to the orthogonal group.  The Lipschitz group contains all elements  of  for which  is invertible in , and these act on  by the corresponding reflections that take  to .  (In characteristic  these are called orthogonal transvections rather than reflections.)

If  is a finite-dimensional real vector space with a non-degenerate quadratic form then the Lipschitz group maps onto the orthogonal group of  with respect to the form (by the Cartan–Dieudonné theorem) and the kernel consists of the nonzero elements of the field . This leads to exact sequences

Over other fields or with indefinite forms, the map is not in general onto, and the failure is captured by the spinor norm.

Spinor norm

In arbitrary characteristic, the spinor norm  is defined on the Lipschitz group by

It is a homomorphism from the Lipschitz group to the group  of non-zero elements of . It coincides with the quadratic form  of  when  is identified with a subspace of the Clifford algebra. Several authors define the spinor norm slightly differently, so that it differs from the one here by a factor of , , or  on . The difference is not very important in characteristic other than 2.

The nonzero elements of  have spinor norm in the group ( of squares of nonzero elements of the field . So when  is finite-dimensional and non-singular we get an induced map from the orthogonal group of  to the group , also called the spinor norm. The spinor norm of the reflection about , for any vector , has image  in , and this property uniquely defines it on the orthogonal group. This gives exact sequences:

Note that in characteristic  the group  has just one element.

From the point of view of Galois cohomology of algebraic groups, the spinor norm is a connecting homomorphism on cohomology. Writing  for the algebraic group of square roots of 1 (over a field of characteristic not  it is roughly the same as a two-element group with trivial Galois action), the short exact sequence

yields a long exact sequence on cohomology, which begins

The 0th Galois cohomology group of an algebraic group with coefficients in  is just the group of -valued points: , and , which recovers the previous sequence

where the spinor norm is the connecting homomorphism .

Spin and pin groups

In this section we assume that  is finite-dimensional and its bilinear form is non-singular.

The pin group  is the subgroup of the Lipschitz group  of elements of spinor norm , and similarly the spin group  is the subgroup of elements of Dickson invariant  in . When the characteristic is not , these are the elements of determinant . The spin group usually has index  in the pin group.

Recall from the previous section that there is a homomorphism from the Lipschitz group onto the orthogonal group. We define the special orthogonal group to be the image of . If  does not have characteristic  this is just the group of elements of the orthogonal group of determinant . If  does have characteristic , then all elements of the orthogonal group have determinant , and the special orthogonal group is the set of elements of Dickson invariant .

There is a homomorphism from the pin group to the orthogonal group. The image consists of the elements of spinor norm . The kernel consists of the elements  and , and has order  unless  has characteristic . Similarly there is a homomorphism from the Spin group to the special orthogonal group of .

In the common case when  is a positive or negative definite space over the reals, the spin group maps onto the special orthogonal group, and is simply connected when  has dimension at least . Further the kernel of this homomorphism consists of  and . So in this case the spin group, , is a double cover of . Please note, however, that the simple connectedness of the spin group is not true in general: if  is  for  and  both at least  then the spin group is not simply connected. In this case the algebraic group  is simply connected as an algebraic group, even though its group of real valued points  is not simply connected. This is a rather subtle point, which completely confused the authors of at least one standard book about spin groups.

Spinors

Clifford algebras , with  even, are matrix algebras which have a complex representation of dimension . By restricting to the group  we get a complex representation of the Pin group of the same dimension, called the spin representation. If we restrict this to the spin group  then it splits as the sum of two half spin representations (or Weyl representations) of dimension .

If  is odd then the Clifford algebra  is a sum of two matrix algebras, each of which has a representation of dimension , and these are also both representations of the pin group . On restriction to the spin group  these become isomorphic, so the spin group has a complex spinor representation of dimension .

More generally, spinor groups and pin groups over any field have similar representations whose exact structure depends on the structure of the corresponding Clifford algebras: whenever a Clifford algebra has a factor that is a matrix algebra over some division algebra, we get a corresponding representation of the pin and spin groups over that division algebra.
For examples over the reals see the article on spinors.

Real spinors

To describe the real spin representations, one must know how the spin group sits inside its Clifford algebra. The pin group,  is the set of invertible elements in  that can be written as a product of unit vectors:

Comparing with the above concrete realizations of the Clifford algebras, the pin group corresponds to the products of arbitrarily many reflections: it is a cover of the full orthogonal group .  The spin group consists of those elements of  that are products of an even number of unit vectors.  Thus by the Cartan–Dieudonné theorem Spin is a cover of the group of proper rotations .

Let  be the automorphism which is given by the mapping  acting on pure vectors.  Then in particular,  is the subgroup of  whose elements are fixed by .  Let

(These are precisely the elements of even degree in .)  Then the spin group lies within .

The irreducible representations of  restrict to give representations of the pin group.  Conversely, since the pin group is generated by unit vectors, all of its irreducible representation are induced in this manner.  Thus the two representations coincide.  For the same reasons, the irreducible representations of the spin coincide with the irreducible representations of .

To classify the pin representations, one need only appeal to the classification of Clifford algebras.  To find the spin representations (which are representations of the even subalgebra), one can first make use of either of the isomorphisms (see above)

and realize a spin representation in signature  as a pin representation in either signature  or .

Applications

Differential geometry
One of the principal applications of the exterior algebra is in differential geometry where it is used to define the bundle of differential forms on a smooth manifold. In the case of a (pseudo-)Riemannian manifold, the tangent spaces come equipped with a natural quadratic form induced by the metric. Thus, one can define a Clifford bundle in analogy with the exterior bundle. This has a number of important applications in Riemannian geometry. Perhaps more important is the link to a spin manifold, its associated spinor bundle and  manifolds.

Physics
Clifford algebras have numerous important applications in physics. Physicists usually consider a Clifford algebra to be an algebra with a basis generated by the matrices  called Dirac matrices which have the property that

where  is the matrix of a quadratic form of signature  (or  corresponding to the two equivalent choices of metric signature). These are exactly the defining relations for the Clifford algebra , whose complexification is  which, by the classification of Clifford algebras, is isomorphic to the algebra of  complex matrices . However, it is best to retain the notation , since any transformation that takes the bilinear form to the canonical form is not a Lorentz transformation of the underlying spacetime.

The Clifford algebra of spacetime used in physics thus has more structure than . It has in addition a set of preferred transformations – Lorentz transformations. Whether complexification is necessary to begin with depends in part on conventions used and in part on how much one wants to incorporate straightforwardly, but complexification is most often necessary in quantum mechanics where the spin representation of the Lie algebra  sitting inside the Clifford algebra conventionally requires a complex Clifford algebra. For reference, the spin Lie algebra is given by

This is in the  convention, hence fits in .

The Dirac matrices were first written down by Paul Dirac when he was trying to write a relativistic first-order wave equation for the electron, and give an explicit isomorphism from the Clifford algebra to the algebra of complex matrices. The result was used to define the Dirac equation and introduce the Dirac operator. The entire Clifford algebra shows up in quantum field theory in the form of Dirac field bilinears.

The use of Clifford algebras to describe quantum theory has been advanced among others by Mario Schönberg, by David Hestenes in terms of geometric calculus, by David Bohm and Basil Hiley and co-workers in form of a hierarchy of Clifford algebras, and by Elio Conte et al.

Computer vision
Clifford algebras have been applied in the problem of action recognition and classification in computer vision. Rodriguez et al propose a Clifford embedding to generalize traditional MACH filters to video (3D spatiotemporal volume), and vector-valued data such as optical flow. Vector-valued data is analyzed using the Clifford Fourier Transform. Based on these vectors action filters are synthesized in the Clifford Fourier domain and recognition of actions is performed using Clifford correlation. The authors demonstrate the effectiveness of the Clifford embedding by recognizing actions typically performed in classic feature films and sports broadcast television.

Generalizations
 While this article focuses on a Clifford algebra of a vector space over a field, the definition extends without change to a module over any unital, associative, commutative ring.
 Clifford algebras may be generalized to a form of degree higher than quadratic over a vector space.

See also

 Algebra of physical space
 Cayley–Dickson construction
 Classification of Clifford algebras
 Clifford analysis
 Clifford module
 Complex spin structure
 Dirac operator
 Exterior algebra
 Fierz identity
 Gamma matrices
 Generalized Clifford algebra
 Geometric algebra
 Higher-dimensional gamma matrices
 Hypercomplex number
 Octonion
 Paravector
 Quaternion
 Spin group
 Spin structure
 Spinor
 Spinor bundle

Notes

Citations

References

 , section IX.9.

 . An advanced textbook on Clifford algebras and their applications to differential geometry.

 ; ibid II (1883) 46; ibid III (1884) 7–9. Summarized in The Collected Mathematics Papers of James Joseph Sylvester (Cambridge University Press, 1909) v III. online and further.

Further reading

External links

 Planetmath entry on Clifford algebras
 A history of Clifford algebras (unverified)
 John Baez on Clifford algebras
 Clifford Algebra: A Visual Introduction

Ring theory
Quadratic forms

Clifford algebra


The 5th New Hampshire Infantry Regiment was an infantry regiment that served in the Union Army during the American Civil War.  The regiment has the unfortunate distinction of having sustained the greatest total loss in battles of any infantry or cavalry regiment in the Union Army, with a total of 295 killed and 756 wounded, for a total of 1,051 men.

Service
The 5th New Hampshire Infantry was organized in Concord, New Hampshire and mustered in for a three-year enlistment on October 22, 1861, under the command of Colonel Edward Ephraim Cross.

The regiment was attached to Howard's Brigade, Sumner's Division, Army of the Potomac, to March 1862. 1st Brigade, 1st Division, II Corps, Army of the Potomac, to July 1863. Concord, New Hampshire, Department of the East, to November 1863. Marston's Command, Point Lookout, Maryland, to May 1864. 1st Brigade, 1st Division, II Corps, Army of the Potomac, to June 1865.

The 5th New Hampshire Infantry mustered out of service June 28, 1865, and was discharged July 8, 1865.

Detailed service
Left New Hampshire for Washington, D.C., October 29, 1861. Camp at Bladensburg, Md., defenses of Washington, D.C., until November 27, 1861. Expedition to lower Maryland November 3–11. At Camp California, near Alexandria, Va., until March 10, 1862. Scout to Burke's Station January 17, 1862 (Company A). Advance on Manassas, Va., March 10–15. Reconnaissance to Gainesville March 20, and to Rappahannock Station March 28–29. Warrenton Junction March 28. Moved to the Virginia Peninsula April 4. Siege of Yorktown, Va., April 5-May 4. Temporarily attached to Woodbury's Engineer Brigade. Construct Grapevine Bridge over Chickahominy May 28–30. Battle of Fair Oaks or Seven Pines May 31-June 1. Seven days before Richmond June 25-July 1. Orchard Station June 28. Peach Orchard, Allen's Farm and Savage's Station June 29. White Oak Swamp and Glendale June 30. Malvern Hill July 1. At Harrison's Landing until August 16. Movement to Fortress Monroe, then to Alexandria and to Centreville, Va., August 16–30. Cover Pope's retreat from Bull Run. Maryland Campaign September–October. Battle of South Mountain, Md., September 14 (reserve). Antietam Creek, near Keedysville, September 15. Battle of Antietam, September 16–17. Duty at Harpers Ferry, W. Va., September 21 to October 29. Reconnaissance to Charlestown October 16–17. Advance up Loudoun Valley and movement to Falmouth, Va., October 29-November 17. Battle of Fredericksburg, Va., December 12–15. Burnside's Second Campaign, "Mud March," January 20–24, 1863. Duty at Falmouth until April. Chancellorsville Campaign April 27-May 6. Battle of Chancellorsville May 1–5. Reconnaissance to Rappahannock June 9. Gettysburg Campaign June 13-July 24. Battle of Gettysburg, July 1–3. Moved to Concord, N.H., July 26-August 3. Duty at Draft Rendezvous, Concord, N.H., until November. Moved to Point Lookout, Md., November 8–13, and duty there guarding prisoners until May 27, 1864. Moved to Cold Harbor, Va., May 27-June 1, and joined the Army of the Potomac. Battles about Cold Harbor June 1–12. Before Petersburg, Va., June 16–19. Siege of Petersburg June 16, 1864, to April 2, 1865. Jerusalem Plank Road June 22–23, 1865. Deep Bottom, north of James River, July 27–28. Mine Explosion, Petersburg, July 30 (reserve). Demonstration north of James River August 13–20. Strawberry Plains August 14–18. Ream's Station August 25. Non-veterans mustered out October 12, 1864. Reconnaissance to Hatcher's Run December 9–10. Dabney's Mills, Hatcher's Run, February 5–7, 1865. Watkins' House March 25. Appomattox Campaign March 28-April 9. On line of Hatcher's and Gravelly Runs March 29–30. Hatcher's Run or Boydton Road March 31. White Oak Road March 31. Sutherland Station April 2. Fall of Petersburg April 2. Sailor's Creek April 6. High Bridge and Farmville April 7. Appomattox Court House April 9. Surrender of Lee and his army. Moved to Washington, D.C., May 2–12. Grand Review of the Armies May 23.

Casualties
The regiment lost a total of 473 men during service; 18 officers and 277 enlisted men killed or mortally wounded, 2 officers and 176 enlisted men died of disease.

Commanders
 Colonel Edward Ephraim Cross - mortally wounded at the Battle of Gettysburg while commanding 1st Brigade, 1st Division, II Corps
 Colonel Charles E. Hapgood - commanded at the Battle of Gettysburg and afterward
 Colonel Welcome E. Crafts - took command after Hapgood was wounded; also took command when the regiment was redesignated as 5th New Hampshire Battalion
 Lieutenant Colonel James E. Larkin
 Major John S. Ricker

See also

 List of New Hampshire Civil War units
 New Hampshire in the American Civil War

References
 Child, William.  A History of the Fifth Regiment, New Hampshire Volunteers, in the American Civil War, 1861-1865 (Bristol, NH:  R. W. Musgrove, Printer), 1893.
 Child, William.  Letters from a Civil War Surgeon:  The Letters of Dr. William Child of the Fifth New Hampshire Volunteers (Solon, ME:  Polar Bear & Co.), 2001.
 Cross, Edward Ephraim.  Stand Firm and Fire Low:  The Civil War Writings of Colonel Edward E. Cross (Hanover, NH:  University Press of New England), 2003.
 Dyer, Frederick H.  A Compendium of the War of the Rebellion (Des Moines, IA:  Dyer Pub. Co.), 1908.
 Pride, Mike & Mark Travis. My Brave Boys:  To War with Colonel Cross and the Fighting Fifth (Hanover, NH:  University Press of New England), 2001.
 Grandchamp, Robert. Colonel Edward E. Cross, New Hampshire Fighting Fifth: A Civil War Biography (Jefferson, NC: McFarland & Company), 2012. .
Attribution

External links
 5th New Hampshire monument at Gettysburg
 5th New Hampshire living history organization
 Story of the 5th New Hampshire at Gettysburg

 The Papers of Ira Barton, Captain of Co. E at Dartmouth College Library

Military units and formations established in 1861
Military units and formations disestablished in 1865
5th New Hampshire Volunteer Infantry
1861 establishments in New Hampshire

5th New Hampshire Infantry Regiment


Dadnab is a free text-messaging service that provides transit information in several major metropolitan areas throughout the United States.  Users of this service can use any text-message enabled cell phone or any other text-messaging device to send a request for information to one of Dadnab's phone numbers, and they can expect an instantaneous response.

Dadnab relies on transit authority databases for the information that it provides.  Queries can cover trip planning, location information, or help requests.  Typically, a Dadnab user will send a text message with an origin and destination to one of Dabnab's phone numbers, and will receive a text message seconds later with routes, stops, departure, transfer and arrival times. Users can also specify desired departure times in their queries.

Roger L. Cauvin, founder and operator of the service, is a longtime resident of Austin, Texas and a frequent user of public transportation.

Service Areas

 Austin, TX
 San Francisco Bay Area
 Chicago, IL
 Dallas, TX
 Houston, TX

 Portland, OR
 Seattle, WA
 Southern California
 Tri-state NY/NJ/CT Area
Boston, MA

External links
Official Website

References

Companies based in Austin, Texas

Dadnab


David Khari Webber Chappelle ( ; born August 24, 1973) is an American stand-up comedian and actor. He starred in and co-created the satirical comedy sketch series Chappelle's Show (2003–2006) before quitting in the middle of production during the third season. After a hiatus, Chappelle returned to performing stand-up comedy across the U.S. By 2006, Chappelle was called the "comic genius of America" by Esquire and, in 2013, "the best" by a Billboard writer. In 2017, Rolling Stone ranked him No. 9 in their "50 Best Stand Up Comics of All Time".

Chappelle has appeared in various films, including Robin Hood: Men in Tights (1993), The Nutty Professor (1996), Con Air (1997), You've Got Mail (1998), Blue Streak (1999), Undercover Brother (2002), Dave Chappelle's Block Party (2005), Chi-Raq (2015) and A Star Is Born (2018). His first lead role was in the 1998 comedy film Half Baked, which he co-wrote. Chappelle also starred in the ABC comedy series Buddies (1996). In 2016, he signed a $20-million-per-release comedy-special deal with Netflix and released six stand-up specials under the deal.

He has received numerous accolades, including six Emmy Awards and four Grammy Awards, as well as the Mark Twain Prize for American Humor in 2019, which is presented by the Kennedy Center as America's highest comedy honor. Chappelle has received two Primetime Emmy Award for Outstanding Guest Actor in a Comedy Series for hosting Saturday Night Live in 2016 and 2020. Chappelle received four Grammy Awards for Best Comedy Album for The Age of Spin (2018), Equanimity & The Bird Revelation (2019), Sticks & Stones (2019) and The Closer (2021).

Early life
David Khari Webber Chappelle was born on August 24, 1973, in Washington, D.C. His father, William David Chappelle III, was a professor of vocal performance and the dean of students at Antioch College in Yellow Springs, Ohio. His mother, Yvonne Seon (, formerly Chappelle), worked for Congolese Prime Minister Patrice Lumumba, is a Unitarian Universalist minister, and worked as a professor and university administrator at several institutions including Wright State University and Prince George's Community College. Chappelle has a stepmother and a stepbrother.

Chappelle grew up in Silver Spring, Maryland, and attended Woodlin Elementary School. His parents were politically active, and family house visitors included Pete Seeger and Johnny Hartman. Hartman predicted Chappelle would be a comedian and, around this time, Chappelle's comic inspiration came from Eddie Murphy and Richard Pryor. After his parents separated, Chappelle stayed in Washington with his mother while spending summers with his father in Ohio. In high school he worked as an usher in Ford's Theatre. He attended DC's Eastern High School for a short time before transferring to Duke Ellington School of the Arts, where he studied theater arts, graduating in 1991.

Career

Early career
Chappelle was featured in a montage of random people telling jokes in the first episode of ABC's America's Funniest People, airing on September 13, 1990. Following his high school graduation, Chappelle moved to New York City to pursue a career as a comedian. He performed at Harlem's Apollo Theater in front of the "Amateur Night" audience, but he was booed off stage. Chappelle described the experience as the moment that gave him the courage to continue his show business aspirations. He quickly made a name for himself on the New York comedy circuit, even performing in the city's parks. In addition to weekend stand-up gigs, he honed his craft at Monday night "open mic" performances at places like the Boston Comedy Club on West 3rd Street, as late as the summer 1994. In 1992, he won critical and popular acclaim for his television appearance in Russell Simmons' Def Comedy Jam on HBO. It was his appearance on this show that allowed his popularity to truly begin rising, eventually allowing him to become a regular guest on late-night television shows such as Politically Incorrect, Late Show with David Letterman, The Howard Stern Show, and Late Night with Conan O'Brien. Whoopi Goldberg nicknamed him "The Kid". At 19, he made his film debut as "Ahchoo" in Mel Brooks' Robin Hood: Men in Tights. He also appeared on Star Search three times but lost to competing comedian Lester Barrie; Chappelle later joked about becoming more successful than Barrie. The same year, Chappelle was offered the role of Benjamin Buford "Bubba" Blue in Forrest Gump. Concerned the character was demeaning and the movie would bomb, he turned down the part. He parodied the film in the 1997 short Bowl of Pork, where a dim-witted black man is responsible for the Rodney King beating, the LA riots and O. J. Simpson's being accused of murder. Chappelle played another supporting role in an early Doug Liman film, Getting In, in 1994. At age 19, he was the opening act for R&B soul singer Aretha Franklin.

Chappelle attracted the attention of television network executives and developed numerous pilots but none were picked up for development into a series. In 1995, he made a guest appearance on an episode of ABC's popular sitcom Home Improvement. The storyline had Chappelle and real-life friend and comedian Jim Breuer ask Tim Taylor for advice on their girlfriends. The characters' single outing in the episode proved so popular that ABC decided to give them their own spin-off sitcom titled Buddies. However, after taping a pilot episode, Breuer was fired and replaced with actor Christopher Gartin. Buddies premiered in March 1996 to disappointing ratings and the show was canceled after only five episodes out of 13 that had been produced.

After the failure of Buddies, Chappelle starred in another pilot. According to Chappelle, the network was uncomfortable with the African-American cast and wanted white actors added. Chappelle resisted and subsequently accused the network of racism. Shortly afterward Chappelle's father died and, after returning to Ohio, he considered leaving the entertainment business.

He later appeared as a stand-up insult comic who targets patrons of a nightclub in the 1996 comedy The Nutty Professor starring Eddie Murphy, one of his major comedic influences. He had a minor role in 1997's Con Air. At the beginning of 1998, he did a stand-up performance for HBO Comedy Half-Hour. That same year, he appeared in "Pilots and Pens Lost", an episode of The Larry Sanders Shows sixth season, in which he and the executives of the show's unnamed television network satirize the treatment that scriptwriters and show creators were subjected to, as well as the executives' knee-jerk tendencies toward racial stereotypes.

He and Neal Brennan co-wrote the 1998 cult stoner film Half Baked, Chappelle's first starring role, about a group of marijuana-smoking friends trying to get their other friend out of jail. It made money at the box office and remains a classic "stoner" film, a genre that includes the Cheech & Chong films as well as more recent fare like Judd Apatow's Pineapple Express. In December 1998, Chappelle appeared as Tom Hanks' character's friend and confidant in You've Got Mail. In 1999, he appeared in the Martin Lawrence film Blue Streak.

In 2000, Chappelle recorded his first hour-long HBO special, Dave Chappelle: Killin' Them Softly, in Washington, D.C. He also starred alongside Norm Macdonald in the 2000 comedy film Screwed. He followed this with an appearance as "Conspiracy Brother" in the 2002 racial satire Undercover Brother.

2003–2006: Chappelle's Show

In 2003, Chappelle debuted his own weekly sketch comedy show on Comedy Central called Chappelle's Show. The show parodied many aspects of American culture, including racial stereotypes, politics and pop culture. Along with comedy sketches, the show also featured musical performances by mostly hip-hop and soul artists. He promoted the work of other black comedians as well, most notably Paul Mooney and Charlie Murphy.

Due to the show's popularity, Comedy Central's new parent company Viacom offered Chappelle a $55 million contract (giving Chappelle a share of DVD sales) to continue production of Chappelle's Show for two more years while allowing him to do side projects. Chappelle has said that sketches are not his favorite form of comedy, and that the show's format was similar to short films.

In June 2004, based on the popularity of the "Rick James" sketch, it was announced that Chappelle was in talks to portray James in a biopic from Paramount Pictures, also owned by Viacom. James' estate disagreed with the proposed comical tone of the film and put a halt to the talks.

That same month, Chappelle recorded his second comedy special, this time airing on Showtime, Dave Chappelle: For What It's Worth, at San Francisco's Fillmore Auditorium, where Lenny Bruce, George Carlin, Richard Pryor, and Robin Williams had performed.

Season 3 problems
In a June 2004 stand-up performance in Sacramento, California, Chappelle walked off the stage after berating his audience for constantly shouting "I'm Rick James, bitch!" which had become a catchphrase from his popular "Rick James" sketch. After a few minutes, Chappelle returned and resumed by saying, "The show is ruining my life." He stated that he disliked working "20 hours a day" and that the popularity of the show was making it difficult for him to continue his stand-up career, which was "the most important thing" to him. He told the audience:

Season 3 was scheduled to begin airing on May 31, 2005, but earlier in May, Chappelle surprised fans and the entertainment industry when he abruptly left during production and took a trip to South Africa. Chappelle said that he was unhappy with the direction the show had taken, and expressed in an interview with Time magazine his need for reflection in the face of tremendous stress:

Immediately following Chappelle's departure, tabloids speculated that Chappelle's exit was driven by drug addiction or a mental problem, rather than the ethical and professional concerns that Chappelle had articulated.

Chappelle's decision to quit the show meant walking away from his $50 million contract with Comedy Central and forming a rift with longtime collaborator Neal Brennan.

The show still plays in syndication on several television networks, despite the relatively small number of episodes compared to most American syndicated television programs. Chappelle's abrupt departure from his show continues to be a focus of interviews and profiles of Chappelle and of Chappelle's own comedy. In Bird Revelation, Chappelle draws an analogy between his departure and the book Pimp, the memoir of Iceberg Slim.

2004: Dave Chappelle's Block Party

Chappelle was the star and a producer of the Michel Gondry-directed documentary Dave Chappelle's Block Party, which chronicles his hosting a free concert in the Clinton Hill neighborhood of Brooklyn on September 18, 2004. Several musical artists, including Kanye West, The Roots, Erykah Badu, Mos Def, Dead Prez and Jill Scott, are featured in the movie both performing in the concert and in conversation off-stage; Chappelle brought Yellow Springs residents to Brooklyn at his own expense. Another highlight of the event was the temporary reunion of 1990s hip-hop group The Fugees.

Chappelle toured several cities in February and March 2006 to promote the film under the name "Block Party All-Stars Featuring Dave Chappelle". Universal Pictures' genre division, Rogue Pictures, released the film in the U.S. on March 3, 2006. It was a success, grossing a total of $11.7 million on a $3 million budget.

2005–2013: Infrequent comedy appearances
In June 2005, Chappelle performed impromptu stand-up shows in Los Angeles, then went on a tour that began in Newport, Kentucky, not far from his Ohio home. On May 11, 2006, he made a prearranged, but quietly marketed, surprise appearance at Towson University's annual Tigerfest celebration. He made another appearance on HBO's Def Poetry, where he performed two poems, titled "Fuck Ashton Kutcher" and "How I Got the Lead on Jeopardy!"

In an interview with Oprah Winfrey that aired on February 3, 2006, Chappelle explained his reasons for quitting Chappelle's Show. He also expressed his contempt for the entertainment industry's tone-deafness regarding black entertainers and audiences:

Chappelle was interviewed for Inside the Actors Studio on December 18, 2005, at Pace University's Michael Schimmel Center for the Arts. The show premiered on February 12, 2006. Four days earlier, he had introduced the musical tribute to Sly Stone at the 48th Annual Grammy Awards.

Chappelle said on Inside the Actors Studio that the death of his father seven years prior influenced his decision to go to South Africa. By throwing himself into his work, he had not taken a chance to mourn his father's death. He also said the rumors that he was in drug or psychiatric treatment only persuaded him to stay in South Africa. He said,

Chappelle said that he felt some of his sketches were "socially irresponsible." He singled out the "pixie sketch" in which pixies appear to people and encourage them to reinforce stereotypes of their races. In the sketch, Chappelle is wearing blackface and is dressed as a character in a minstrel show. According to Chappelle, a white crew member laughed during its filming in a way that made him uncomfortable, saying "It was the first time I felt that someone was not laughing with me but laughing at me."

During this time, Chappelle did not rule out returning to Chappelle's Show to "finish what we started," but promised that he would not return without changes to the production, such as a better working environment. He wanted to donate half of the DVD sales to charity. Chappelle expressed disdain at the possibility of his material from the unfinished third season being aired, saying that to do so would be "a bully move," and that he would not return to the show if Comedy Central were to air the unfinished material. On July 9, 2006, Comedy Central aired the first episode of Chappelle's Show: The Lost Episodes. After the DVD release, Chappelle was interviewed by Anderson Cooper on CNN and reiterated he would not return to Chappelle's Show. An uncensored DVD release of the episodes was made available on July 25.

Chappelle has been known to make impromptu and unannounced appearances at comedy venues, and continues to do so following his post–Chappelle's Show return to stand-up comedy.

In April 2007, Chappelle set a stand-up endurance record at the Laugh Factory Sunset Strip comedy club, beating comedian Dane Cook's record of three hours and 50 minutes. In December of the same year, Chappelle broke his own record with a time of six hours and 12 minutes. Cook reclaimed the record in January 2008, with a time of seven hours. On November 19, 2009, Chappelle performed at the Laugh Factory again, where it was speculated that he would attempt to take back the record. However, according to the club owner, he was disqualified after he left the stage five hours into his routine.

Chappelle again appeared on Inside the Actors Studio and, in celebration of the show's 200th episode, he interviewed the show's usual host, James Lipton. The episode aired on November 11, 2008. He appeared again on Inside the Actors Studio in 2013, for its 250th episode.

In February 2009, Chappelle did a four-hour set at Comic Strip Live in New York.

In August 2011, Chappelle appeared at Comedy Jam in San Francisco.

2013–2017: Career comeback

In August 2013, Chappelle returned to full-time touring stand-up, as a headliner, when he was featured during the Oddball Comedy & Curiosity festival. Sponsored by Funny or Die, Chappelle co-headlined with comedy act Flight of the Conchords.

During a stop in Hartford, Chappelle walked off the stage due to heckling from the crowd that lasted throughout his entire performance. The heckling was so raucous that it drowned out Chappelle's voice over the P.A. system and included chants of "White Power", a line used in a Chappelle's Show episode, that was viewed as wildly uncalled-for and out-of-context by other audience members who later wrote about the event. A few days later, Chappelle stopped in Chicago for a performance. The comedy website ComedyHype.com acquired and released audio of him on stage responding to the heckling. Chappelle referenced the Hartford incident, stating that "young, white, alcoholic[s]" should be blamed for the prior incident, that he hoped North Korea would bomb Hartford, that in the future he would not stop in Hartford for gas, and finally summarizing his feelings on the situation by saying, "Fuck Hartford!" However, in August 2014 Chappelle returned to Hartford for a surprise appearance at the 2014 Oddball Festival and received standing ovations during his set.

In June 2014, Chappelle made his first major New York City appearance in eleven years, performing ten nights at Radio City Music Hall. Chappelle promoted the dates by appearing on The Today Show, The Tonight Show Starring Jimmy Fallon and Late Show with David Letterman.

In 2015, Chappelle appeared in the Spike Lee film Chi-Raq, his first film role in 13 years.

On November 12, 2016, Chappelle made his hosting debut on Saturday Night Live the weekend of Donald Trump winning the 2016 presidential election. The show also featured A Tribe Called Quest as the musical guest. In his opening monologue, Chappelle tackled Trump and the election head on. He ended his monologue by stating, "I'm wishing Donald Trump luck, and I'm going to give him a chance, and we, the historically disenfranchised, demand that he give us one too." His performance on SNL received widespread acclaim from critics and audiences alike. At the 69th Primetime Emmy Awards, he received an Emmy Award for Outstanding Guest Actor in a Comedy Series for his appearance. He donated the Emmy to his former high school while filming an episode of Jerry Seinfeld's Netflix series, Comedians in Cars Getting Coffee (Season 10, Episode 2: "Nobody Says, 'I Wish I Had A Camera'").

On November 21, 2016, Netflix announced that they would be releasing three new stand-up comedy specials from Chappelle in 2017, with Chappelle being paid $20 million per special. The first two specials were released on Netflix on March 21, 2017, and hail directly from Chappelle's personal comedy vault. "Deep in the Heart of Texas" was filmed at Austin City Limits Live in April 2015, and "The Age of Spin" was filmed at the Hollywood Palladium in March 2016. The specials marked the comedian's first concert specials released in 12 years, and proved to be an immediate success as Netflix announced a month later that they were the most viewed comedy specials in Netflix's history.

The third special, Equanimity, was filmed in September 2017 at the Warner Theater in Washington, D.C., and then on November 20, 2017, Chappelle filmed a fourth special, The Bird Revelation, at The Comedy Store in Los Angeles. On December 22, 2017, Netflix announced the expansion of the deal to include The Bird Revelation, which was released with Equanimity on December 31.

2018 and 2019

In January 2018 at the 60th Annual Grammy Awards, Chappelle received a Grammy Award for Best Comedy Album for his first two 2017 specials The Age of Spin & Deep in the Heart of Texas. In September 2018, Chappelle's Equanimity special received an Emmy Award for Outstanding Variety Special (Pre-Recorded). In October 2018, Chappelle returned to the big screen as "Noodles", Jackson Maine's best friend and retired musician in Bradley Cooper's directorial debut, a remake of A Star Is Born. The film was a massive critical and commercial success. He was nominated along with the cast for the Screen Actors Guild Award for Best Cast in a Motion Picture. In 2018, Chappelle and Jon Stewart joined forces for a duo comedy tour in the United States, and across the United Kingdom. He has also collaborated with Aziz Ansari for three stand-up shows in Austin, Texas, at the Paramount Theater.

In February 2019, Chappelle was nominated for and won the Grammy Award for Best Comedy Album for Equanimity and Bird Revelation.

In 2019, Chappelle was chosen to receive the annual Mark Twain Prize for American Humor presented by The Kennedy Center. President of the Kennedy Center Deborah Rutter stated "Dave is the embodiment of Mark Twain's observation that 'against the assault of humor, nothing can stand'... and for three decades, Dave has challenged us to see hot-button issues from his entirely original yet relatable experience." The set of people honoring Chappelle included Jon Stewart, Bradley Cooper, Morgan Freeman, Lorne Michaels, Tiffany Haddish, Aziz Ansari, Sarah Silverman, Neal Brennan, Q-Tip, Mos Def, John Legend, Frederic Yonnet, Erykah Badu, Common, SNL cast members Kenan Thompson, Michael Che and Colin Jost, as well as Eddie Murphy. The Prize was awarded at the Kennedy Center gala on October 27, 2019. The ceremony was broadcast on PBS January 7, 2020. The Mayor of the District of Columbia, Muriel Bowser, declared the day of the award ceremony "Dave Chappelle Day" in Washington, D.C.

On August 26, 2019, Chappelle's fifth Netflix special, Dave Chappelle: Sticks & Stones, was released. The special garnered controversy (receiving an average score of 5.70 from Rotten Tomatoes critics), and backlash for jokes about abuse allegations against singers Michael Jackson and R. Kelly, as well as for jokes about the LGBT community and cancel culture. However it received overwhelming praise from audiences (with a 99% audience approval rating on Rotten Tomatoes) and in 2020, Sticks & Stones won the Grammy Award for Best Comedy Album.

2020
On June 12, 2020, Netflix released 8:46, a 27-minute and 20-second video of newly recorded stand-up by Chappelle on the YouTube channel "Netflix Is a Joke". The private event was held outdoors on June 6, 2020, in Yellow Springs, Ohio, where audience members observed social distancing rules and wore masks to prevent the spread of COVID-19. The title was chosen in reference to the 8 minutes and 46 seconds that police officer Derek Chauvin knelt on the neck of George Floyd, a black man, murdering him. Chappelle touches on Floyd's murder and subsequent protests and takes aim at Don Lemon, Laura Ingraham and Candace Owens.

Expanding on the concept of the socially distanced comedy presentation, beginning with a pair of performances in late June 2020 and officially kicking off with a Fourth of July celebration, "Chappelle and friends" hosted what became known as "Chappelle Summer Camp", which brought live performances to a masked, socially distanced audience at Wirrig Pavilion, in Yellow Springs, Ohio. These shows featured regular performances from comedians Michelle Wolf, Mohammed Amer and Donnell Rawlings, as well as Chappelle's tour DJ, DJ Trauma and frequent special guests including Jon Stewart, Chris Rock, Louis CK, Sarah Silverman, David Letterman, Bill Burr, Michael Che, Brian Regan, Chris Tucker, Kevin Hart, Ali Wong, Trevor Noah, Tiffany Haddish, with musical guests John Mayer, Common, and many others. After several shows in July, some issues arose from neighbors' complaints of noise and disturbances, local zoning officials granted a special variance allowing the performances to continue through October 4, 2020. The Chappelle Summer Camp series of shows ended suddenly September 25, 2020, when Elaine Chappelle announced in a closed Facebook fan group that there had been a possible COVID-19 exposure in their inner circle, and all further performances were canceled.

It was announced that Chappelle would return to host Saturday Night Live the weekend of the 2020 United States presidential election, his second time giving a post-presidential election monologue. Due to the effect of the COVID-19 pandemic on the vote count, the results were delayed and announced earlier that Saturday. In response to unfounded allegations that Joe Biden's presidency had been stolen from Donald Trump, Chappelle's offered jokes ranging from Trump's handling of the pandemic to his resulting legacy, and the political future of the United States, in his 16-minute opening monologue:

Critics and audiences praised the monologue describing it as "scathing", "illuminating", and "powerful."

In December 2020, Chappelle's company, Iron Table Holdings purchased a fire station near his Yellow Springs, Ohio, home, with plans to convert it into a comedy club. He also retrofitted a mechanic's garage in the same village into a clubhouse, and dubbed it "The Shack", for podcasting.

2021–present
On October 5, 2021, Chappelle starred in his sixth and final Netflix special The Closer. In The Closer, Chappelle made jokes about gay and transgender people, particularly transgender women, that some considered transphobic. Simultaneously, Chappelle argued that he was not anti-transgender, bringing up his opposition to North Carolina's anti-transgender bathroom laws and his friendship with the late Daphne Dorman. The special was met with some backlash, including from students of Chappelle's alma mater Duke Ellington School. On October 20, Netflix employees organized a walkout demonstrating their support of the transgender community, and demanded that The Closer be taken off of Netflix. CEO Ted Sarandos acknowledged that "storytelling has real impact in the real world" but refused to take down the special, stating that he "does not believe it falls into hate speech."  In November 2021, Saturday Night Live lampooned the controversy during its Weekend Update segment, stating, "A Washington D.C. art school is postponing renaming its theater, after alumni Dave Chappelle's Netflix controversy. Well, of course, because God forbid, you should name a building after someone problematic in Washington D.C." In summer of 2022, Chappelle announced that he would not give his name to the Duke Ellington School theater, instead insisting it should be named the Theater for Artistic Freedom and Expression.

Dave Chappelle: Live in Real Life, a documentary covering Chappelle's concerts in Yellow Springs during the COVID-19 pandemic, premiered at Tribeca Film Festival in June 2021, followed by a series of roadshow events in the United States and Canada and a limited theatrical release on November 19, 2021.

In the early hours of May 4, 2022, Chappelle was performing at the Hollywood Bowl in Los Angeles, California, as part of the Netflix is a Joke Fest, where he was tackled onstage by a member of the audience, who was swiftly subdued by security. The attacker was later found to have been armed with a replica handgun containing a knife blade. Chappelle's 4-night stint at the Hollywood Bowl ties him with Monty Python for the most headlined shows by a comedian at the venue.

On November 12, 2022, Chappelle hosted Saturday Night Live for the third time. On February 5, 2023, he received his fourth Grammy Award for Best Comedy Album for The Closer.

During an October 19, 2023 show in Boston, Chappelle described Israel's actions during the 2023 Israel-Hamas war as war crimes. Chappelle also condemned the United States for aiding Israel and condemned Hamas for its October 7th attacks. The audience reaction to Chappelle's statements was mixed; some audience members cheered, some heckled, and others walked out.

Influences
In his interview with Inside the Actors Studio host James Lipton, he said that his biggest influences in comedy are Richard Pryor, Eddie Murphy, Mort Sahl, Chris Rock, Paul Mooney, and Mel Blanc.

When asked about his earliest influence in comedy, Chappelle said:

When asked about the biggest influence on him in comedy, Chappelle spoke of Richard Pryor:

Awards and accolades

Chappelle has received many awards and nominations for his work in stand-up and television including three consecutive Grammy Awards for Best Comedy Album. He has also received five Primetime Emmy Awards and one Screen Actors Guild Award nomination along with the ensemble of A Star Is Born.

In 2017, Columbia, South Carolina Mayor Steven Benjamin declared February 3 "Dave Chappelle Day" when Chappelle spoke at the Chappelle Auditorium at Allen University, a building named after his great-grandfather, Bishop William David Chappelle, who worked at the university.

In 2019, Chappelle was awarded the prestigious Mark Twain Prize for American Humor at the John F. Kennedy Center for Performing Arts. Those to honor Chappelle at the event included Jon Stewart, Bradley Cooper, Aziz Ansari, Sarah Silverman, Chris Tucker, Frederic Yonnet and Lorne Michaels. The award ceremony was turned into a television special and released on Netflix and received a Primetime Emmy Award for Outstanding Variety Special (Pre-Recorded) nomination.

His work, as well as that of Margaret Cho, was also the subject of a book by Canadian dramaturg Elizabeth Ludwig, American Stand-Up and Sketch Comedy, that was published at the end of 2010.

Activism and advocacy

Philanthropy
In 2004, he donated his time to Seeds of Peace International Camp, a camp located in Otisfield, Maine, which brings together young leaders from communities in conflict.

Chappelle supports his high school, Duke Ellington School of the Arts. He has financially contributed to the school over the years, visited and gave a commencement speech. During his acceptance speech at the 2017 Emmy Awards, Chappelle gave a shout-out to D.C. Public Schools. In November 2021, the school was set to rename their auditorium in Chappelle's honor. Following controversy in response to jokes made in The Closer, the renaming ceremony was delayed until April 2022. Instead, Chappelle made an unannounced stop at the school to host a school assembly and Q&A session, asking only students who had an issue with Chappelle to come forward to ask questions. Following the assembly, the school decided to go forward with renaming the auditorium, respecting the wishes of school co-founder Peggy Cooper Cafritz.

Politics
Chappelle endorsed Andrew Yang in the 2020 United States presidential election.

In December 2021, Chappelle told the Yellow Springs, Ohio, village council that he would cancel his planned business investments, including his restaurant and comedy club, if it approved a zoning change to allow a multifamily affordable housing project. The affordable housing had been negotiated between the village and the developer as a condition of approval for its plan to build 143 single-unit homes. On February 7, 2022, he again spoke up against the zoning change at the council meeting held to vote on the approval, calling the council "clowns" and reminding them that his business was worth $65 million a year. The council failed to approve the change, deadlocking at 2–2, with one recusal. He has also criticized the city of San Francisco in a stand-up.

Personal life
Chappelle married Elaine Mendoza Erfe in 2001. The couple have two sons, and two daughters. They live on a  farm near Yellow Springs, Ohio. Chappelle also owned several houses in Xenia, Ohio. He told Yellow Springs' residents in September 2006:

Chappelle converted to Islam when he was 17. He told Time magazine in May 2005:
 Chappelle appears in a video explaining the religious history of the Well of Zamzam in Mecca. He has also explained that his faith helped him use his career to benefit people.

His great-grandfather Bishop William D. Chappelle, born into slavery in 1857, served as a president of Allen University and led a delegation of African Americans who met President Woodrow Wilson at the White House. His great-great-grandfather Robert J. Palmer was a member of the South Carolina Legislature, then majority black, during Reconstruction. His grand-uncle W. D. Chappelle Jr. was a physician and surgeon who opened the People's Infirmary around 1915, a small hospital and surgery practice in Columbia, South Carolina, during a time when segregation prevented many African Americans from having access to healthcare.

Discography

Live albums

Other charted songs

Filmography

Film

Television

Stand-up specials

References

External links

 "Transcripts: Interview with Dave Chappelle". Anderson Cooper 360, July 7, 2006. CNN.

 "If He Hollers Let Him Go". The Believer, October 2013. Rachel Kaadzi Ghansah.

1973 births
Living people
20th-century African-American people
21st-century African-American people
20th-century American comedians
21st-century American comedians
20th-century American male actors
21st-century American male actors
20th-century Muslims
21st-century Muslims
African-American film producers
African American–Jewish relations
African-American male comedians
American male comedians
African-American Muslims
African-American stand-up comedians
American sketch comedians
American stand-up comedians
African-American television producers
American comedy writers
American male film actors
American male non-fiction writers
American male screenwriters
American male television actors
American male voice actors
American satirists
Audiobook narrators
Comedians from Maryland
Comedians from Ohio
Comedians from Washington, D.C.
Converts to Islam
American Muslims
Film producers from Ohio
Grammy Award winners
Journalists from Ohio
Male actors from Maryland
Male actors from Ohio
Male actors from Washington, D.C.
Mark Twain Prize recipients
Muslim male comedians
People from Silver Spring, Maryland
People from Xenia, Ohio
People from Yellow Springs, Ohio
Primetime Emmy Award winners
Screenwriters from Maryland
Screenwriters from Ohio
Screenwriters from Washington, D.C.
Third Man Records artists

Dave Chappelle


Louis Philippe, Crown Prince of Belgium (24 July 1833 – 17 May 1834), was the eldest child and heir-apparent of King Leopold I of the Belgians and his second wife, Louise of Orléans. He died as an infant. He may have been named after his grandfather Louis Philippe I.

Life
Louis Philippe became crown prince at birth in Laeken. His birth was announced by the sound of 101 cannon shots at the capitol, Brussels. The baby was baptised at the Collegiate church of St. Michael and St. Gudule at Brussels.

Death and burial
Louis-Philippe died of an inflammation of the mucous membranes. According to his father, this was completely preventable. His funeral was held on 24 May 1843. He was buried in the Mausoleum of the Dukes of Brabant at the Collegiate church of St. Michael and St. Gudule. He is now burried in the chapel of Church of Our Lady of Laeken (Notre Dame de Laeken), near his family's tomb. This church did not exist at the time of his death. His mother died in 1850 and wanted to be buried at Laeken near the royal residence. Construction for the church began in 1854. It houses the royal crypt where the royal family is buried. A contemporary source recorded his passing: "The family of King Leopold are plunged into the deepest distress by the sudden death of the Duke of Brabant, the heir-apparent to the throne." He was followed as crown prince upon the birth of his younger brother, Leopold (Léopold Louis Philippe Marie Victor), who would later succeed their father as Leopold II, King of the Belgians. Leopold was the replacement child to Louis-Philippe.

Titles and Styles
His tombstone records his titles as: "S.A.R. (Son Altesse Royale or Royal Highness) le Prince Louis-Philippe Duc le Brabant".

24 July 1833 – 16 May 1834 His Royal Highness The Crown Prince of Belgium, Prince of Saxe-Coburg and Gotha, Duke of Saxony.

Ancestry

References

Belgian princes and princesses
1833 births
House of Saxe-Coburg and Gotha
Heirs apparent who never acceded
1834 deaths

Louis Philippe, Crown Prince of Belgium


William Charles Renshaw (3 January 1861 – 12 August 1904) was a British tennis player active during the late 19th century, who was ranked world No. 1. He won twelve Major titles during his career. A right-hander, he was known for his power and technical ability which put him ahead of competition at the time. Renshaw shared the all-time male record of seven Wimbledon singles titles with American Pete Sampras until 2017 when Roger Federer won his eighth singles title. His six consecutive singles titles (1881–86) is an all-time record. Additionally he won the doubles title five times together with his twin brother Ernest. William Renshaw was the first president of the British Lawn Tennis Association (LTA).

Career
Renshaw won a total of twelve Wimbledon titles. His record of seven singles titles, which Pete Sampras tied in 2000, was surpassed in 2017 when Roger Federer won his  eighth title. The first six were consecutive, an achievement which has been unequalled to this day. Since 1922 the reigning champions have had to play in the main draw, making such feats considerably more difficult. In the summer months he would compete in England and Ireland, while competing on the French Riviera during the winter months and practising on a private tennis court he and his brother had built at their own cost. In singles play he played his twin brother Ernest Renshaw three times (1882, 1883 and 1889) in the Wimbledon final, triumphing on all three occasions. He was unable to defend his title in 1887 because of tennis elbow, the first time this injury received public attention, and during his absence took up golf. The other five titles were in the Gentlemen's doubles, partnering with Ernest. Additionally, he and his brother dominated the sport for many years in a time when the only other Grand Slam was the U.S. Championships, and by custom players did not travel far. The rise in popularity of tennis in this period became known as the 'Renshaw Rush'. In 1888 William was elected the first president of the British Lawn Tennis Association (LTA). In 1983, William Renshaw was elected posthumously into the International Tennis Hall of Fame together with his brother.

Death
He died in Swanage, Dorset on 12 August 1904, aged 43, of epileptic convulsions. In 2020, a street in Leamington Spa was named after his brother and him, Renshaw Drive.

Grand Slam finals

Singles (7 titles, 1 runner-up)

Doubles (5 titles)

Records

All-time

See also

 List of Grand Slam men's singles champions

References

External links

1861 births
1904 deaths
19th-century English people
19th-century male tennis players
English male tennis players
Grand Slam (tennis) champions in men's singles
Grand Slam (tennis) champions in men's doubles
International Tennis Hall of Fame inductees
Sportspeople from Leamington Spa
English twins
Wimbledon champions (pre-Open Era)
British male tennis players
Tennis people from Warwickshire

William Renshaw


Robert Francis Boyle (October 10, 1909 – August 1, 2010) was an American film art director and production designer. He was nominated for four Academy Awards for North by Northwest (1959), Gaily, Gaily (1969), Fiddler on the Roof (1971), The Shootist (1976) before winning the Honorary Academy Award in 2008. He was also nominated for a Primetime Emmy Award for The Red Pony (1973).

Boyle is also known for his work on Alfred Hitchcock's North by Northwest (1959), The Birds (1963), and Marnie (1964). He also was the art director for The Russians Are Coming, The Russians Are Coming (1966), How to Succeed in Business Without Really Trying (1967), In Cold Blood (1967), and The Thomas Crown Affair (1968), Mame (1974), and Private Benjamin (1980).

Early life
Born in Los Angeles, Boyle trained as an architect, graduating from the University of Southern California (USC). When he lost his job in that field during the Great Depression, Boyle found work in films as an extra.

Career
In 1933 he was hired as a draftsman in the Paramount Pictures art department, headed by supervising art director Hans Dreier. Beginning with Cecil B. DeMille's The Plainsman, Boyle went on to work on a variety of pictures as a sketch artist, draftsman and assistant art director before becoming an art director at Universal Studios in the early 1940s.

Boyle collaborated several times with Alfred Hitchcock, first as an associate art director for Saboteur (1942) and later as a full-fledged production designer for North by Northwest (1959), The Birds (1963), and Marnie (1964). Denied permission to shoot footage on Mount Rushmore, Hitchcock turned to Boyle to create realistic replicas of the stone heads.

Boyle abseiled down the monument, photographing its contours in detail, before constructing "just enough to put the actors on so we could get down shots, up shots, side shots, whatever we needed." Almost two decades earlier, Boyle had delivered the Statue of Liberty reproduction that was used in the climactic scene of Saboteur.  For The Birds, Boyle was put in charge of the title characters. He later recalled, "We needed to find out which birds we could use best, and finally settled on two types: sea gulls, which were very greedy beasts that would always fly toward the camera if there was a piece of meat, and crows, which had a strange sort of intelligence." Boyle described his relationship with Hitchcock: "It was a meeting of equals: the director who knew exactly what he wanted, and the art director who knew how to get it done."

When director Norman Jewison failed in his attempts to get the necessary submarine that was at the center of his The Russians Are Coming, the Russians Are Coming storyline, Boyle built a working model from styrofoam and fiberglass.

Boyle's other credits include It Came from Outer Space, Cape Fear, In Cold Blood, Fiddler on the Roof, Portnoy's Complaint, Winter Kills, W.C. Fields and Me, The Shootist, Private Benjamin, Staying Alive, and Troop Beverly Hills.

During the course of his career, Boyle was nominated four times for the Academy Award for Best Art Direction, but never won. In 1997 he received the Art Directors Guild's Lifetime Achievement Award, and he was voted an Honorary Academy Award by the Board of Governors of the Academy of Motion Picture Arts and Sciences, "in recognition of one of cinema's great careers in art direction," which he received during the 80th Academy Awards ceremony on February 24, 2008.

At the age of 98, Boyle became the oldest winner ever of an Honorary Award in the history of the Academy Awards. In ill health and arriving to the ceremony in a wheelchair, Boyle insisted on walking onstage, alongside Nicole Kidman, to receive the honor. He was the subject of the Academy Award-nominated documentary short The Man on Lincoln's Nose (2000).

Personal life and death
Boyle's wife, Bess Taffel, whose career began in the Yiddish theatre, was a Hollywood blacklistee, whose film career ended in 1951 after she was "named" by Leo Townsend, although her husband's career was apparently unharmed. They lived in a house that Bob designed and built in The Hollywood Hills, for their entire marriage.

Unable to have children of their own, they adopted two girls; Emily Rebecca Boyle, in 1956 and Susan Anne Boyle (Licon) in 1959. He also worked at the American Film Institute's Center for Advanced Film Study program in Los Angeles as the Production Design instructor.

A widower since 2000, Boyle died on August 1, 2010, in Los Angeles due to natural causes.

Awards and nominations

See also
 Art Directors Guild Hall of Fame

References

External links

Robert Boyle papers, Margaret Herrick Library, Academy of Motion Picture Arts and Sciences

1909 births
2010 deaths
Academy Honorary Award recipients
American art directors
American centenarians
American production designers
Men centenarians
People from Los Angeles
USC School of Architecture alumni

Robert F. Boyle


"Sentir" is a song recorded by Cuban recording artist Jon Secada for his debut self-titled studio album and for his debut Spanish-language album Otro Día Más Sin Verte (1992). It was released in 1993 as the fourth single from his Spanish-language album. The Spanish version peaked at number one on the US Billboard Hot Latin Tracks chart, making Secada the first Hispanic artist to do so. It was composed by Secada, Miguel Morejon, and Joseph Stefano, while Emilio Estefan Jr. produced the piece.

Production and success
Jon Secada was the backup vocalist for Cuban singer Gloria Estefan in 1989. Secada became close friends with Gloria and her husband, Emilio Estefan Jr., who helped guide Secada into the music business. Secada released his self-titled debut album in 1992 with SBK Records. The recording made up of English-language compositions and two Spanish-language tracks. It was certified triple platinum by the Recording Industry Association of America (RIAA), denoting shipments of three million copies. Secada, with the help from Emilio, decided to release an all Spanish-language album. During the recording sessions, Secada confirmed that Gloria helped translate his English-language recordings into Spanish. He said that she told him to record songs that he would be comfortably fine with singing throughout his career as a singer. She also told them not to "translate everything literally" but to "keep the same theme of the song in play."

"Sentir" was released as the fourth single from his Spanish album. It peaked at number one on the US Billboard Hot Latin Tracks chart ending on July 3, 1993. Secada became the first Latin artist to place four number one singles from a single album on the US Billboard Hot Latin Tracks chart. Spanish Latin pop singer Enrique Iglesias broke Secada's record with five number one singles from his self-titled album in 1997. "Sentir" was the seventh best-performing Latin single on the Hot Latin Tracks year-end chart in 1993.

Chart performance

Weekly charts

Year-end charts

Credits and personnel
Credits are taken from the album's liner notes.

Jon Secada — vocals, composer
Miguel Morejon — composer
Joseph Stefano — composer
Emilio Estefan Jr. — producer

References

Sources

1993 singles
1992 songs
Jon Secada songs
Spanish-language songs
Song recordings produced by Emilio Estefan
Songs written by Jon Secada
EMI Records singles
Songs written by Miguel A. Morejon

Sentir