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Oral History Transcript — Dr. P. A. M. Dirac
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P. A. M. Dirac; May 6, 1963
ABSTRACT: Part of the Archives for the History of Quantum Physics oral history collection, which includes tapes and transcripts of oral history interviews conducted with ca. 100 atomic and quantum physicists. Subjects discuss their family backgrounds, how they became interested in physics, their educations, people who influenced them, their careers including social influences on the conditions of research, and the state of atomic, nuclear, and quantum physics during the period in which they worked. Discussions of scientific matters relate to work that was done between approximately 1900 and 1930, with an emphasis on the discovery and interpretations of quantum mechanics in the l920s. Also prominently mentioned are: Niels Henrik David Bohr, Max Born, Boyland, Louis de Broglie, Johannes Martinus Burgers, Paul Ehrenfest, Ralph Fowler, Peter Fraser, Werner Heisenberg, Ernst Pascual Jordan, Cornelius Lanczos, Edward Arthur Milne, Wolfgang Pauli, David Robertson, Ernest Rutherford, Erwin Schrödinger, John Joseph Thomson, Hermann Weyl; University of Cambridge, Delta Squared V Club, Kapitsa Club, Københavns Universitet, Merchant Venturers School in Bristol, University of Bristol, and Universität Göttingen.
Session I | Session II | Session III | Session IV | Session V
Kuhn:Id really like to get a clearer idea of what you may actually have covered In school science and mathematics, then later at Birmingham, and at Cambridge.
Dirac:In the first place it was Bristol, not Birmingham. I went to a very good science school in Bristol, a Merchant Ventures School. They just concentrated on science and on modern languages. They didnt teach Latin or any kind of classics at all. Just a little bit of history and geography. I didnt like the arts side of it. I feel I was very lucky to get to this good school. The school shared the same building with the technical college. Its a school in the daytime and a technical college in the evening so all the laboratories of the technical college were available to the school. We had very good laboratory facilities. Then another thing which helped me was that as soon as I went to this secondary school the war started. That meant that the older boys were taken away, called up for war work, the higher classes were empty and they pushed on the younger boys as quickly as they could. So I got pushed on ahead and learned science earlier than I would otherwise have done.
Kuhn:Was it quite unusual to have no classical languages in a school of this sort?
Dirac:Well, most secondary schools would teach Latin. This one didnt.
Kuhn:Did. that mean that it was designed to prepare people particularly for technical schools?
Dirac:Well, it was meant to give a good scientific education. I dont know of any school now which concentrates so much on science as that one did.
Kuhn:But would it mean, for example, that students who had graduated from there generally could not go to Oxford or Cambridge without Latin in that day?
Dirac:They would have to take Latin as a separate subject; not everyone had to go into it.
Kuhn:What sort of schools would most of them have gone to?
Dirac:. . . They would go to Bristol University or other modern universities.
Kuhn:Would. they be particularly likely to go into the sciences or engineering?
Dirac:They would from that school.
Kuhn:Can you tell me more about what subjects you would actually have prepared there in the sciences?
Dirac:No biological sciences. That hadnt come into the ordinary school work then, but (we had) physics, chemistry, mathematics; mathematics was divided into algebra, geometry, trigonometry. Of course I was soon working independently in mathematics — independently of the class. I was just given books to read which I worked through by myself.
Kuhn:Do you remember what books?
Dirac:Well, there was Edwards Calculus, differential calculus and Integral calculus. I think it was Hall and (Knight's) Geometry, Im not sure. I dont remember very clearly what the books were. I know we did not stick to Euclid, We had more modern methods of geometry than Euclid. There were mainly the science courses and courses in English, French and German. We had three hours a week in each of these subjects.
Kuhn:How much would have been in the physics course?
Dirac:There may have been three hours a week of lecturing and one afternoon of practical work.
Kuhn:Just for the one year?
Dirac:I think all the time. Chemistry also I started quite early because of being pushed on on account of the war. I remember my chemistry master, Mr. Boyland, believed in teaching chemistry in the modern way and he introduced atoms and chemical equations very early, in the course. I think in almost my first lecture in chemistry he introduced me to these things. We learned about atomic weights and we did not learn about equivalent weights. I think even now in school in chemistry they spend a lot of time on equivalent weights and only go on to atomic weights later on. I know my daughter was learning quite a lot about equivalent weights.
Kuhn:Well, I think I had them both but I think I had atomic weights before I had equivalent weights.
Dirac:Yes. I hardly ever heard of equivalent weights. I hardly knew what they meant. Well, do you have any other questions?
Kuhn:What sort of subjects in physics would you actually have gotten - through using how much of the accompanying mathematics either by yourself or in the course?
Dirac:It was only in mathematics that I worked by myself, in the other subjects I worked in the class. I dont remember. I suppose they were just the usual things. Heat, and light and sound. It was spread over four years, you see. I had four years in that school.
Kuhn:Where you worked by yourself in mathematics in that school, did you then come back and talk to the teacher about this or did you simply tell him that you had read the books?
Dirac:I expect I talked to him a bit. I think I was mostly on my own. I was just allowed to read what interested me. I took the same exams as the rest of the class. They were no problem to me.
Kuhn:Were you reading at this time by yourself in other subjects? I dont necessarily mean academic subjects. Did you read novels? Or poetry?
Dirac:I read some novels. In fact, one was supposed to do it in connection with the English lessons. I was always a slow reader and I didnt like poetry. In fact, I never understood good poetry.
Kuhn:Well, this was not something you went on with, particularly then on your own as you did with the math.
Dirac:No, no. My whole interest was on the scientific side. I was really very ignorant of matters outside my schoolwork.
Kuhn:I think you were also quite interested at tines in economics.
Dirac:Not at that stage.
Kuhn:When did that begin?
Dirac:I was never very much interested in economics. Who said that I was?
Kuhn:Im not sure. You gave an economic example in your Nobel address, for example. Someone spoke also of an occasion when you had talked on, I think, an economic, perhaps a social, problem when you might at least equally well have talked about matters more strictly scientific.
Dirac:It must have been much later because... Certainly not in that period at all. I took no interest in political things either.
Kuhn:Now let me ask you about subjects and courses at Bristol.
Dirac:In the school or university?
Kuhn:Now I mean at the university, assuming that we have done this now for the pre-university.
Dirac:Well, I was in electrical engineering at Bristol and that was in the same building again as this school and the technical college. They were all together. The faculty in engineering was quite small then. They were all housed in the same building so that when I went to the university I continued to go to the same building. To some extent I had the same teachers. I specialized in electrical engineering and I was mainly influenced by the professor of electrical engineering there called David Robertson. He was extremely methodical. He taught both theoretical and practical work. I remember how methodical he was with the practical work, impressing upon people the need to arrange things so as to avoid the possibility of accidents. He was paralyzed from polio and he rode around everywhere. He was paralyzed in his legs and he went around everywhere in a wheelchair. So he had to arrange his own life methodically.
Kuhn:This made no great problems for him in teaching the practical work?
Dirac:Well, he could go around in his wheelchair and see what everyone was doing and explain things to them.
Kuhn:How theoretical was the teaching for electrical engineering of electromagnetic theory or how much of electromagnetic theory as such did you get in that curriculum?
Dirac:Well, engineers just concentrate on the equations that give the right answers. They dont want to know the reasons for those equations. I learned the equations and how to use them - - all about inductance, capacitance and so on, how to work out electrical circuits and the rules for winding electrical motors and dynamos. I found it was quite interesting mathematics in some of these rules. I am grateful to David Robertson for explaining these things in a way which did show the mathematical beauty of some of the things which one had to calculate.
Kuhn:Did one go as deep as Maxwells equation?
Dirac:We didnt do electrical waves at all. Wireless didnt exist as a regular thing.
Kuhn:So this was really for power engineering.
Dirac:Yes, yes.
Kuhn:Did you learn to do what I once learned to call Heaviside calculus?
Dirac:I did a bit of that with solving differential equations, linear differentials equations with constant coefficients. I was just taught it as a rule that worked. I couldnt explain very well why they did work, but still they did work and gave the answer that you wanted, and that was enough to satisfy engineers.
Kuhn:Were you impressed with that?
Dirac:There is some sort of magic about it, yes. It was strange bow you could get the answers out.
Kuhn:I had just a taste of it and didnt really get back to it until I began to learn a little bit about operator techniques and delta functions. You had these in the reverse order and I wondered whether they had any kinship.
Dirac:Well, I was just first taught the way to — the rules which one had to use to get. the right result.
Kuhn:Ive got no notion how specialized or how quickly specialized the electrical engineering curriculum would have been. Did you do simply electricity or did you...
Dirac:Well, there was some amount of general engineering, for instance, testing materials, pulling things until they break and calculating the breaking stress, and things like that. We had quite a good deal about calculating stresses in structures.
Kuhn:Would you have had a general dynamics course along with this?
Dirac:Yes, yes. One had to know about the dynamics. There was quite a good deal of general engineering in the work.
Kuhn:Was the approach to the scientific problems generally rather different from what one would have had if one had been in physics or was this quite a lot the same?
Dirac:I think it was different in the sense that they just concentrated on learning equations that give the right answer. Then you could proceed to work out the answer with slide rules.
Kuhn:Were you at all impelled yourself at that point to push back to a more basic source for these formulas?
Dirac:I dont think I felt impelled to it. I think at that time I wasnt really doing much inquiring; it was just absorbing the knowledge which was given to me. I think it was! probably that sort of training that first gave me the idea of a delta function because when you think of loads in engineering structures, sometimes you have a distributed load and sometimes you have a concentrated load at the point. Well, it is essentially the same whether you have a concentrated load or a distributed one but you use somewhat different equations in the two cases. Essentially it s only to unify these two things which sort of led to the delta function.
Kuhn:Do you think you did try to unify them at that time?
Dirac:Not at that time. Oh, no. Not at that time at all. But I just felt that they were essentially the same even though the treatment was different. There was a lot to be done just calculating stresses and things like that. Maybe the stress on a whirling shaft, and I found that some of the mathematics was quite p:nDtty even though the whole work ±3 approximate. I think I owe a lot to my engineering training because it did teach me to tolerate approximations. Previously to that I thought any kind of an approximation was really intolerable. One should just concentrate on exact equations all the time. Then I got the idea that in the actual world all our equations are only approximate. We must just tend to greater and greater accuracy. In spite of the equations being approximate they can be beautiful.
Kuhn:When you say approximate here, I think people often use the same term in two rather different ways. This may mean that they give approximate results in the sense that engineering equations do. It may mean that the whole physical theory with which the equations are involved is approximate in the sense that its an approach to whats really there.
Dirac:Well, its just neglecting a lot of factors. I meant it in that sense. The actual situation is far too complicated, you have to neglect a lot of factors.
Kuhn:Would you say that one gets the Bohr atom from quantum mechanics or that one gets to quantum mechanics from the Bohr atom by adding simply a factor that one has been ignoring previously, which would give a sense of approximation?
Dirac:You mean by quantum mechanics the Schrödinger equation.
Kuhn:The Schrödinger equation or the general -. I mean would that also be an example of an approximation in the sense that you have in mind?
Dirac:Yes, it would be. Yes.
Kuhn:Because clearly the logical relation of the earlier and later theory there is more complex; that is, it would be difficult to isolate a single — or group of extra things, that sort of added on
Dirac:I think its very likely that all our equations are only approximate. Our present quantum theory is probably only an approximation to the improvement of the future. I feel that everything might be an approximation and this comes very largely from the engineering training.
Kuhn:I think this question may arise again when we come back to some of the problems presented by quantum mechanics. You may be willing to elaborate it because I think most engineers idea of what is involved in the approximation is that there may be a complete theory, an exact theory, which you must know in order to know what youre neglecting.
Dirac:I dont think thats the engineering approach. I think they have a general feeling about what is important and what can be neglected. That would make a good engineer. Probably would make a good physicist also.
Kuhn:But this is a sense of an approximation in which one doesnt t ask except perhaps intuitively to know what the full series would be in order to justify dropping the term.
Dirac:Yes, yes. You just rely on your general intuition. Thats certainly so for engineers.
Kuhn:Very good. In addition, were you doing anything over and above your engineering studies at this point as you had gone ahead by yourself with math at school?
Dirac:I continued to go ahead with math and I was interested in relativity. You see, just at that time relativity sort of burst on the world. That was 1918 when the war ended and relativity had a tremendous effect on the general public. Pews- papers were full of articles on relativity and magazines also. very one was talking about relativity, It was a new philosophy and ft produced more excitement I third than science has ever produced before or since. Of course, engineering students were also interested in it and talked about it. And during in my later period I worked on it. I told you that I went to Professor Broads lectures. remember I was also interested in other things, philosophy and logic. I got a copy of Mills from the library and read that all through. I found it pretty dull, but still I stuck to it, and tried to understand these things. I thought at that time that maybe philosophy was important. Since then the field of philosophy has terribly declined. I feel that philosophy will never lead to important discoveries. Its just a way of talking about discoveries which have already been made.
Kuhn:What else did you read in philosophy?
Dirac:I cant remember reading any other books.
Kuhn:Were there philosophical problems that you talked to people about or worried about yourself? Bohr, for instance, talked a good deal about how concerned he had been at one time with the problem of the freedom of the will.
Dirac:I never talked to people about it. I thought about it, but found that sort of problem insoluble. I did think a lot about these things but I never came to any definite conclusions.
Kuhn:Do you remember what the particular problems were?
Dirac:I think I told you that one time I thought that space and time might be connected and that you might have to rotate space and time axes together. But I only knew about Euclidean space then and, of course it wont work with Euclidean space. So I had to give up with that.
Kuhn:Were some of the more usual philosophical problems like the freedom of the will, the reality of other minds?
Dirac:I thought about those things, yes. Cant remember anything definite that this thinking led to.
Kuhn:You spoke, when you talked before about relativity, about having gotten hold of Eddington s book. Were there other books at that point that you were particuiar1y working in yourself?
Dirac:I dont think so, no. Eddingtons book was the first mathematical book on relativity.
Kuhn:Well, Ive noticed when you get up to Cambridge you start publishing quite soon. Your second semester. Now clearly youve got a very good command of statistical mechanics. Did that all happen while you were there?
Dirac:No. I might say that there was a good deal of controversy at that time between Eddington and Jeans and some of the students were very interested in that. One of the students that I was especially friendly with called Wilshire used to be very keen to read letters in Nature which Eddington and Jeans had written.
Kuhn:This was a controversy over relativity?
Dirac:Ive forgotten what it was about. No, I think it was some astronomical thing. One can look it up. Wilshire was also interested in relativity and we had talks about that together.
Kuhn:You said that you thought your choice of engineering was probably largely determined by the fact that your brother had done this.
Dirac:Yes, and also it was in the same building and a natural thing for students to go on to. I suppose I didnt know then that one could get ones living in pure science.
Kuhn:Mad you been tempted to do mathematics, for example? It was the thing you had been reading by yourself.
Dirac:It was the thing which interested me most but I did not know that one could get a living by it. No one ever spoke to me about it. Engineering was something which one could earn ones living from and I knew that.
Kuhn:Well, teaching mathematics, would you have thought of that as a way of raking ones living?
Dirac:I didnt like teaching very much. Of course, I thought I could have been a school teacher but I didnt like it.
Kuhn:So you think probably that you considered mathematics as a possibility and rejected it because it meant school-teaching which you didnt want to do.
Kuhn:Row did you feel about the practical work in engineering? Youve spoken of the appeal of engineering approximations, but what about the manipulative, mechanical soldering-side of electrical engineering?
Dirac:I dont suppose I was very good at it. On one long occasion I went to a factory to get some practical training in engineering work. They sent an unfavorable report on me to my professor, so I presume I didnt do very well.
Kuhn:Did you enjoy the more manipulative part —.
Dirac:I enjoyed it, yes, but I was extremely ignorant of anything which I hadnt learned in class. I was just lacking in., common sense, I suppose.
Kuhn:Did you ever do experimental work after you madc the transition to physics?
Dirac:I did a very little at one time, yes.
Kuhn:I ran onto a letter, which I think was printed in the Fermi volume, from Rutherford to Fermi in response to some news about the early neutron work. Rutherford congratulates Fermi on turning to experimental work and then says that youre also. doing some experimental work so there s hope for theoretical physics.
Dirac:Yes. I did a little work on trying to separate isotopes by centrifugal methods.
Kuhn:How did you core out with that? I know were out of chronological order, but were not likely to come back to this one by the logic of your paper.
Dirac:Well, I was a close friend of Kapitza at that time and I think he interested me in it and persuaded me to take up some experimental work; I had the idea that maybe just the rotation of gases at high speed without any mechanical moving parts could be used for separation of isotopes. I did some experiments on it and got a negligible amount of separation, but I got another effect which I wasnt expecting which was interesting, namely a thermal effect. I was able to produce something like a conjuring trick. I just showed three pipes, pumped in some air into one pipe; have the one pipe here branching out into two pipes and the air would come out of these two pipes at different temperatures, widely different temperatures.
Kuhn:They were coming off symmetrically?
Dirac:Well, I mean there were some asymmetry in the apparatus but the apparatus was so small that it was concealed- . I believe we had differences of about maybe 1000 centigrade.
Kuhn:At what temperature?
Dirac:The pressure was about six atmospheres. Maybe not quite that much; but below freezing point on one side, and the other side quite high. Comes entirely from the viscosity effects. The inner layers have a higher angular velocity than the outer ones and the viscosity transfers energy from the inner layers to the outer ones. The outer ones go out one side and the inner ones come out the other side and theres quite a big temperature difference.
Kuhn:Did anything further come of that?
Dirac:I tried to see whether there was any separation when one used a mixture of gases and it seemed to me the simplest way to try that would be to put some scent in it, the scent being some heavy gas, and see whether more scent comes out one side than the other but it turned out later that it was just due to the fact that ones sense of smell is very much keener at low temperatures than at high temperatures. The temperature effect quite dominated any other effect.
Kuhn:When you say you had thought of mathematics and felt that there was not a living to be made there, was physics a career one would even think of at this time?
Dirac:I never thought of it. No one ever spoke to me of it as a career. I did not come into contact with the physics and mathematics people at the university because they were in quite a different building a half a mile away. I never went to that building. I was entirely at this Merchant Ventures College.
Kuhn:Do you mean to be taken literally when you suggest that its being in the same building was perhaps a major factor in the choice?
Dirac:I think it was quite an important factor, yes. And the same people, same staff, to some extent. This David Robertson, for instance, who was my physics teacher in the school, I also - -.
Kuhn:So it was really because these were the subjects you enjoyed and you went right on with them.
Dirac:Yes. With the same professor.
Kuhn:I see that more clearly now. Id taken it initially to mean, Why go a half mile away to another building? But I see much more now the sense of continuity in a subject which you liked and were doing well with.
Dirac:Yes. The people there rather took it for granted that I would continue in that way.
Kuhn:Well, the last time you talked, you said that you had heard later that the mathematicians were quite disappointed that you decided to do engineering,
Dirac:Yes, yes.
Kuhn:This sounds as though the mathematics was once a more live option, as though they might have either persuaded you to do it or you had talked about doing it or something.
Dirac:They had heard about my good examination results and they hoped that I would specialize in mathematics.
Kuhn:But they didnt try to persuade you?
Dirac:I never heard anything of it. Perhaps its going too far to say they never did anything, but if they did, it a skipped my mind. Well, going back to this centrifugal force, theres one further thing to add. When Kapitza was detained in Russia, I rather stopped. I didnt have enough enthusiasm to carry on without him and so nothing further was done on it until the war came and people wanted to separate isotopes of uranium and the subject was taken up again some modified apparatus was experimented with in Oxford. I went to Oxford from time to time to talk with the people there who were doing experiments. There is a possibility of getting small effects from the separation of gases by rotations which are produced without any mechanical moving parts.
Kuhn:It never, I take it, was done on a major scale?
Dirac:No, I dont think it was good enough to compete with the diffusion method. That was all the experimental work that I did as a physicist. Of course, I had to do a lot during my training in school and in the university.
Kuhn:You said before that when you first went into the school of mathematics at Bristol, you really started first by going back to engineering school because you had not been able to get an engineering job in the depression.
Dirac:That is so, yes. This professor, David Robertson, told me I shouldnt waste my time hanging around doing nothing and that I should go back and do some research. —He started me off on a problem with Stroboscopes, and after a few weeks there the mathematics people asked me to go and study mathematics with free tuition.
Kuhn:Well, this is clearly the beginning of your way back or your way to physics. But I take it earlier if youd suddenly heard of an engineering job, you would have taken it.
Kuhn:Is there anything identifiable as a point of decision?
Dirac:Well, I really went over to mathematics in that period, not physics.
Kuhn:Yes. But is there a point at which it suddenly becomes clear to you that youre not going to go to an engineering job if it does become available?
Dirac:No, I dont think theres any definite occasion like that. I stopped applying for jobs when I went to study the mathematics at Bristol.
Kuhn:And so far as you remember you never did open that up again.
Dirac:No, I never applied again. Well, having started on a course, I wanted to finish it.
Kuhn:That was a two-year course from the beginning, was it?
Dirac:Yes. It would normally be a three-year course but with my previous training they let me off a year. There was another choice that had to be made, because in the first year of that two-year course one did pure and applied mathematics together, half and half. The second year one had to specialize in either pure or applied. So I didnt really know which to choose. I didnt mind very much between then. There were just two students doing the honors course then, a girl, called Miss Dent, and me. The professors, of course, wanted both of us to choose the sane option because it would mean only half as much teaching for them to do. But Miss Dent was very definite that she wanted to do applied and that was why I did applied mathematics rather than pure. Again, its rather fortuitous that I got onto the path of applied mathematics.
Kuhn:What subjects did you do — this would be a course that met every day?
Dirac:Oh, yes. There were lectures every day, I think. Well, when I was doing both pure and applied, I was very much influenced by Peter Fraser whom I told you about. I learned projective geometry from him and I found it very interesting. It was really a fascinating subject. I found an article about Fraser (looks for article). You might like to look at it. You can take it along and read it.
Kuhn:Thank you. Do you remember where its from?
Dirac:Hodge wrote it, and you could ask him. Professor Hodge is in Cambridge.
Kuhn:Well, I shall take that along and have a look at it and bring it back. Im very glad to see it.
Dirac:Id say he was the best teacher I ever had.
Kuhn:Did you have him just in this one course?
Dirac:No, he taught other things also, rigorous foundations in mathematics, how to differentiate and integrate with rigor. I previously had just learned the rules well enough for engineering and I found it rather hard to appreciate that rigor was needed. It seemed to me that when you were confident that a certain method gave the right answer, you didnt have to bother about rigor. In fact, I still feel rather that way. But Fraser did a: very good job of persuading one of the need of rigor.
Kuhn:Did any of your math get you more toward algebra?
Dirac:By algebra do you mean sort of noncommutative stuff?
Kuhn:Well, at least something more - just a class of variables that dont necessarily have to be numbers.
Dirac:I remember reading about quaternions by myself. I never had it in class but I did get hold of an old book on quaternion's.
Kuhn:Do you have any notion what that would have been
Dirac:Well, there werent very many books on quaternion's. Who was it, Thomson, Tait?
Kuhn:There are some quaternions in Thomson and Tait.
Dirac:This is a book entirely on qunternions. A big thick book,
Kuhn:That thick book on quaternions would not be Thomson and Tait.
Dirac:There werent very many books on quaternions in those days. They talked about tensors and versors. It was an old-fashioned book.
Kuhn:Good. Im much interested. Youve mentioned Thomson and Tait and knowing something about quaternions from that last time we talked - -.
Dirac:Maybe Thomson and Tait is the wrong book and I read something else.
Kuhn:But you do remember there being a book on quaternions by themselves. How did you like that?
Dirac:I liked it in some ways, but I didnt appreciate it to the full extent because the authors did talk about tensors and versors for the scalar and vector parts and they rather separated the scalar and vector parts too much, instead of thinking of the two together as one entity. They put the wrong emphasis on it. So I didnt appreciate it as much as I ought to have done if Id had a better book.
Kuhn:This connects with something you said last time that puzzled me a good deal, because I think in talking about the projective geometry with Fraser, you said that ever since then your own approach has been largely geometrical.
Kuhn:I was somewhat puzzled about this because I would myself have thought of your approach as being very often algebraic, but I probably wouldnt have even raised this except that as you may know Oppenheimer arrived in Copenhagen just before I left. He sends you his greetings. We were talking bit together about you and he came out, without my having raised this at all, with a remark about your immense facility as an algebraist. This has been somewhat my own feeling but runs dead counter to this remark of yours. I wonder if I could vex you by asking you to say a little bit more about what you d had in mind.
Dirac:Well, Im not altogether sure what is meant by algebraist. If it means some- one who simply carries through masses of algebraic calculation without picturing what the equations mean, then Im just no good at it. All this modern work about dispersion relations and reggi-poles and things like that I find very difficult to follow. It doesnt impress me strongly at all because I dont see the geometrical connections.
Kuhn:I would think of your peculiar q-number manipulations, for example, as being algebraic rather than geometric.
Dirac:Yes, but I only used them in an elementary way. Perhaps I didnt tell you that I kept up my connection with geometry some time after I came to Cambridge. There was a Professor Baker, a professor of geometry, who used to give tea parties on Saturday afternoons to people who were keen on geometry; after the tea someone would give a talk on some recent research work on none geometrical subject. I went to those tea-parties and absorbed quite a lot of geometry then. I talked once or twice myself. I remember I worked out a new method in projective geometry and gave a talk about that at one of these meetings. I never published this method. Well, thats a good deal about working with the geometry of four or more dimensions. Four dimensions were very popular then for the geometrists to work with. It was all done with the notions of projective geometry rather than metrical geometry. So I became very familiar with that kind of mathematics in that way. Ive found it useful since then in understanding the relations which you have in Minkowski a space. You can picture all the directions in Minkowski space as the points in a three-dimensional projective space. The relationships between vectors, null-vectors and so on - - and you get at once just the relationships between points in a three-dimensional vector space. I always used these geometrical ideas for getting clear notions about relationships in relativity although I didnt refer to them in my published works.
Kuhn:Did this also give you techniques that were relevant to your approach to quantum theory whether relativistic or not?
Dirac:No. It doesnt connect at ail with non-commutative algebra.
Kuhn:It is all right to think of that as being algebraic.
Dirac:Yes, yes. But I dont think youll find any heavy algebra in any of my work.
Kuhn:No. There is an awful lot of algebraic sense, though its hard to know how to put that more precisely; but I think with many people who find the approach to a multiplication relation more general than XY, where these cannot be thought of as numbers, it suddenly gets away from them as a subject matter. Youve clearly made this exception with ease and facility, at a time, I take it, when it wasnt the standard thing to do.
Dirac:Yes, I suppose. Non-commutative algebra was a rather strange idea in those days, although it shouldnt have been because of quaternions. Hello, come on in. (Someone enters room)
Kuhn:I think we were talking about the transition from engineering to math and I think it might be appropriate to go on now to the transition from math to physics.
Dirac:When I came to Cambridge, yes.
Kuhn:I take it that although you had had a year in which you turned out to be in applied math, this wasnt necessarily to be a career with the subject matter that you ultimately went on with.
Dirac:Not necessarily, no.
Kuhn:Did you think of yourself as going to Cambridge to do applied, math?
Dirac:It was already when I was finishing my engineering course, my father sent me to Cambridge to try for a scholarship. Actually, it was too late when he thought of it to try for the honorary scholarships because the examinations for the honorary scholarships are in December but St. Johns College offered some exhibitions for which the examinations were held in June. I went and took that examination and they offered me an exhibition of 70 pounds a year. I wasnt able to get any other money to supplement it and it wasnt enough to come to Cambridge with. Thats why I stayed on in Bristol. But after the two years in Bristol I was awarded a government grant from the Department of Scientific and Industrial Research and with the help of that I was able to come to Cambridge.
Kuhn:Could you also take up the previous scholarship?
Dirac:Yes. The previous exhibition. They allowed me to take it up two years later. It was still a very small amount of money, but just enough to manage with.
Kuhn:Was your father able to help you at all?
Dirac:He didnt seem to want to anyway and I did get by entirely, in this way, independently of my father. He left quite a bit when he died, but at that time he didnt think he could afford it.
Kuhn:If you had gone to Cambridge immediately after finishing your engineering course, would you have gone into applied mathematics or mathematics?
Dirac:To begin with, one doesnt specialize. I would have had to specialize later. dont know how it would have turned out.
Kuhn:Well, since you had already finished your engineering work, youd have had some idea of going to study something.
Dirac:It would have been mathematics, yes.
Kuhn:Well, in that sense there really wasnt as much accident involved as I had thought before in the transition from engineering to mathematics in the graduate school at Bristol.
Dirac:That was made quite independently of my having won this exhibition in Cambridge.
Kuhn:But at least you would have gone on to do mathematics at Cambridge. Well, coming back now to when you actually do go there in 23, youd had a good deal of mathematics in the meantime. Was it the sort of mathematics by that time that meant that you were thinking of a career in teaching?
Dirac:I didnt like the idea of being a school-teacher anyway.
Kuhn:Did that seem the likely outcome?
Dirac:Well, if I wasnt very good, it might have been the only possibility. I didnt like the idea of becoming a schoolteacher.
Kuhn:The other alternative was university teaching?
Dirac:Yes. I didnt know whether Id be good enough for that.
Kuhn:Clearly you had impressed an awful lot of people quite a lot; was there real doubt in your own mind about the likely outcome of this?
Dirac:I was really very ignorant of the world. I had done well on examination but that was all. I had no idea what the standard was in Cambridge.
Kuhn:You went there more or less with an eye to continuing in more advanced subjects in mathematics?
Dirac:To do research. The government grant that I got was specifically for doing research
Kuhn:You didnt have to have a particular research project.
Dirac:No, no.
Kuhn:It was research in mathematics, but it might have been anywhere in mathematics.
Dirac:Yes, yes. So I came to Cambridge as a research student and not as an undergraduate. That was why I was able to come without knowing Latin. If I had gone to Cambridge earlier as an undergraduate I would have had to suddenly learn Latin.
Kuhn:Did you attempt to pick up research problems virtually on arrival, or did you go to lectures and read at first?
Dirac:Well, Fouler was appointed as my supervisor.
Kuhn:This was immediately on arrival.
Dirac:Yes. I think perhaps I first went to see Cunningham. I had seen Cunningham previously when I came for the examination for the exhibition. I was rather hoping that Cunningham would be my supervisor. He worked in electromagnetic theory and I thought that was an interesting subject. Cunningham couldnt take me. I dont quite know why. I was assigned to Fouler and his interest was statistical mechanics and I thought that to be a relatively ugly subject.
Kuhn:Had you looked at it at all before?
Dirac:Not really, no. Cunningham is still alive, by the way; if youd like to ask him any questions you probably could. He lives here in Cambridge. Well, Fowler set me to think about this question of dissociation under a temperature gradient.
Kuhn:At the very start?
Dirac:Pretty near the beginning, yes. He also gave me things to read and lectures to go to. Fouler himself was giving lectures on quantum theory, I believe. It was then that I first learned about the Bohr atom. I was quite surprised to find that atomic theory had developed to such a large extent.
Kuhn:Do you still have notes on those lectures?
Dirac:Its possible that I have them. I dont remember where they are; I could look for them.
Kuhn:It would be terribly helpful to have a precise idea. at what level, over what illustrations and subject matter Fowler was actually lecturing at that quite key point. So if you do have those I think we would like very much to microfilm them.
Dirac:I also went to Cunninghams lectures. He was lecturing on classical electrodynamics. I went to lectures on thermodynamics. I believe that was by Newman. Newman gave some lectures on relativity and so on. He is now in Manchester. I went to the Colloquia at the Cavendish. We sometimes had visitors from foreign places. Bohr came and lectured sometimes. Of course, I was very happy to meet Bohr. I was also very happy to meet I1dington, because I had heard about him. so much in my engineering student days. Eddington was the great man then. He brought relativity to England, and he led that eclipse expedition to check the Einstein effect in 1919. That aroused tremendous public interest.
Kuhn:Did you go to lectures of Eddington at that time, or courses of lectures?
Dirac:I cant remember whether I did or not. I dont remember now.
Kuhn:Well, there are all sorts of subjects coming in quickly now that are really new to you. I mean the electromagnetic theory ties somewhat to your previous engineering training, but must go a great deal beyond it. Statistical mechanics is a subject which was perhaps quite new.
Dirac:Yes, yes. Lennard-Jones was in Cambridge at the time. I learned quite a bit from him. Well, I got introduced to the Boltzmann equation for the first time. 891 This was a starting point for statistical mechanics. .1 also learned some astrophysics from Milne. During one term when Fowler went to Copenhagen Mime was appointed my supervisor and he set me on that astrophysical problem on which I wrote a little paper.
Kuhn:Unless my impression is wrong, when you came to Cambridge you start on more advanced work, but really the whole subject matter broadens out.
Kuhn:Now, at least from the point of view of the American vocabulary, you are doing physics as you had not previously been doing physics. Many of these subjects are applied mathematics or astronomy at Cambridge — this is not the natural way to describe it.
Dirac:Well, the electromagnetic theory was really physics.
Kuhn:Could you have had many of these same subjects at Bristol or did they simply not exist there?
Dirac:Statistical mechanics and thermodynamics I dont think existed at Bristol.
Kuhn:Electromagnetic theory probably did?
Dirac:Yes, but not the waves. Not electromagnetic waves. I learned a little about the lagrangian and a little about the Hamiltonian.
Kuhn:But that existed in the sense of potential theory problems.
Dirac:Yes, quite a lot of potential theory problems.
Kuhn:Well, I would be grateful if you could look at some point and see what lectures you may have notes on. It would help to pin down content of lectures more specifically and there may very well be a few of those that wed like to microfilm.
Dirac:I think my notes are pretty rough. In any ease, I didnt absorb very much from lectures. I got a more thorough understanding from private reading than from lectures.
Kuhn:Do you remember again books you read in this period?
Dirac:Sommerfeld was the main book. Sommerfelds Atombau and Spectralinien.
Kuhn:You read that in the German. There was an English translation-
Dirac:It was an English translation, but it was rather a bad one. I think I read it in the German. I had read some Gcrman in school and it turned out to be rather inadequate. Still, with the help of a dictionary, I was able to plod along and gradually got more fluent with it.
Kuhn:But Fowlers statistical mechanics was not out yet.
Dirac:Oh, no. Not till much later. But I read a good many papers and periodicals.
Kuhn:What periodicals would you have been likely to follow at that point?
Dirac:The Proceedings of the Royal Society, and the Zeitschrift fur Physik, that was the main physics journal in those days. Annalen der Physik I recall. I dont know whether the Physical Review existed then. It wasnt very important.
Kuhn:Yes, it did exist, but I find almost nobody who would have been likely to be reading it in Europe. It had existed for a while, but was not an international journal.
Dirac:Well, the Zeitschrift fur Physik was the main physics journal in those days. And it was from reading these papers that I got ideas for problems in research work.
Kuhn:Some of those also must have come from teachers. That is, Fowler you say put you on right at the start.
Dirac:He definitely put me on this first problem as soon as I arrived.
Kuhn:Is it that second one that is the relativity dynamics of a particle?
Dirac:Thats just a very short note. That was suggested by something that Eddington had written and Fowler had talked about. Seers that I could put things a little more clearly than he had them. Yes, it was in Eddingtons book.
Kuhn:That came out of the book you think rather than from taking a course with him?
Dirac:I think it came out of a book, yes.
Kuhn:The paper you do on the Doppler principle and the Bohr condition that may well come out of reading.
Dirac:Yes, what was the title of that paper?
Kuhn:Note on the Doppler Principle and the Bohr Frequency Condition.
Dirac:I expect it did. Ive forgotten that paper. Was that in the Cambridge
Kuhn:Yes. Thats the
Dirac:I think that did come from private reading.
Kuhn:Well certainly there is a relevant paper of Bohrs that you point to thats In the supplement to the Cambridge Proceedings.
Dirac:Yes, I think this sort of work came just from reading things and noting that its possible to improve what someone else has written
Kuhn:In connection with your next paper on the detailed balancing in the Proceedings of the Philosophical Society [Royal Society A 106], Id like to ask whether by any chance you knew of de Broglie s work in this period.
Dirac:1924, was it?
Dirac:I did know about it and I wasnt strongly impressed by it because it seemed to me to be a mathematical curiosity. I didnt take these waves as something physically real in the way that Schrodinger did. It never occurred to me to try to generalize it for particles which are not moving uniformly. I looked upon it just as a mathematica1 curiosity.
Kuhn:Do you remember how you knew of it, because there are lots of people who were totally unaware that it existed in this period.
Dirac:I think de Broglie had published something about it. I had read about it.
Kuhn:Do you remember where?
Dirac:I dont remember where, no.
Kuhn:The thesis itself, although it was published in full in French, was not often read; there was however an article in the Phil. Mag., that summarized it.
Dirac:I probably got it from that.
Kuhn:Fowler was the one who transmitted the article to the Phil. Mag., I think it was Ellis that was responsible for its being there in the first place because he had been at Maurice de Broglies lab. But I wonder whether you bad ever heard Fowler speak of it or remembered other conversations about it.
Dirac:No, I don1t remember Fowler speaking about it. I dont think its the sort of thing that would impress Fowler Fowlers in interests were in statistical mechanics and the Bohr orbits also.
Kuhn:Well, of course this tied to both of those, you know. That is, de Broglie had a derivation for the quantum condition or for the Bohr orbit in terms of the interference and he also got some quite interesting statistical results. So Im not sure whether those were in the article or not.
Dirac:I didnt know he had any statistical results. I think it was just speculative what he said about the possibility of connecting these waves with quantum condition. It was just a speculation. I dont think people took it seriously. Nobody except Schrodinger took it seriously.
Kuhn:Einstein took it fairly seriously, I think. There are an awful lot of people who simply didnt know it existed. There was nothing equivalent to the Phil article printed in any German journal that I know of. So by and large it was unknown to people who didnt follow the French literature. I was really led to ask you this question in the first place because of the one passage in the paper on detailed balancing in which I supposed probably you were speaking directly to the de Broglie paper.
Dirac:I dont think I referred to it in any [part of the paper].
Kuhn:You certainly didnt cite it. It was this on page Its that paragraph. [End of § 5. For the discussion of equilibrium problems, quanta of radiation cannot be regarded as very small particles of tatter moving with very nearly the speed of light.]
Dirac:Well, so far as concerns the light quanta and the electromagnetic waves, de Broglie s ideas were common to everybody but the idea of extending them to other particles with non-zero rest mess was a new thing, which people, did not take seriously.
Kuhn:But de Broglie, so far as I know, is the only one who in talking about light quanta talks of them as having a very small but finite rest mass and a velocity correspondingly just a little bit less than the velocity of light. That is, most people simply give them the velocity of light and zero mess. Dc Broglie from the start talks of having a very finite mass and a velocity slightly less than the velocity of light and you phrase this point on what I agree is in general a veil-known idea of light quanta. But this phraseology strongly suggests to me that maybe youre thinking of de Broglies version of it.
Dirac:Id better think this over and see if I can remember any more about it.
We ought to go and have our tea now.
Session I | Session II | Session III | Session IV | Session V


text: Hello friends I am planning to buy a new Maruti Swift Dzire 2012 this week but I am really confused between these two colors Silky Silver or Glistering Grey. But when I saw the colors I am getting more confused as not able to understand which color to choose so guys please help me out which color should I go for? And let me know as soon as possible.

subset: commoncrawl


text:
Math of the World
There's math in Native American beadwork, African fabrics, modern music, and even cornrow hairstyles.
By Emily Sohn, 00:00 AM October 30, 2006
If you know where to look, you can find math anywhere you go.
Math is not just in the numbers on a cash register or at a football game. It's in bathroom-tiling patterns, the shapes of clouds and trees, the arrangement of a flower's petals, a ball's path in a pinball game, the knots you tie in your shoelaces—and even in the way you lace your shoes (see "How to Lace Like an Ace").
There's math in the spiral pattern at the center of a flower.
|Kenneth Peterson
Ron Eglash has gone even farthe...
Source URL: https://student.societyforscience.org/article/math-world


text:
CARE welcomes ceasefire in South Sudan, but a comprehensive peace settlement must be reached
JUBA, South Sudan. (Feb. 2, 2015) — CARE welcomes the signing of the ceasefire between the government and opposition forces in South Sudan.
CARE is one of the world's largest private international humanitarian organizations, committed to helping families in poor communities improve their lives and achieve lasting victories over poverty. The organization was founded in 1945, when 22 American organizations came together to rush lifesaving CARE Packages® to survivors of World War II. CARE quickly became a trusted vehicle for the compassion and generosity of millions. Originally located in New York City, we moved our headquarters to Atlanta, Georgia, in 1993. We are located at 151 Ellis Street, NE, Atlanta, Georgia 30303-2440 USA.
Keep learning:
In October 1993, the global poverty-fighting organization CARE moved its headquarters to Atlanta. Twenty years later, we held a celebration marking the special anniversary.
We seek a world of hope, tolerance and social justice, where poverty has been overcome and people live in dignity and security.
How American food aid can hurt local farmers
Check out these great letters to the editor by members of the CARE Action Network.
WASHINGTON (Feb. 4, 2014) - CARE applauds the Senate approval of reforms to the U.S. international food assistance program contained in the 2014 Farm Bill under the leadership of Sen. Debbie Stabenow (D-MI), working with Sen. Thad Cochran (R-MS), and House colleagues, Rep. Frank Lucas (R-OK) and Rep. Collin Peterson (D-MN).
This paper briefly summarizes our analyses, options and directions on food resources and spending on food aid.
CARE applauds the House and Senate Farm Bill conferees, under the leadership of Senate Chairwoman Debbie Stabenow (D-MI), Ranking Member Cochran (R-MS), House Chairman Lucas (R-OK) and Ranking Member Peterson (D-MN)), for including significant, common-sense, lifesaving reforms to the U.S. international food assistance program.
Washington, D.C. (January 21, 2014) – The FY14 Omnibus Spending Bill (Consolidated Appropriations Act of 2014), recently signed into law by President Obama is a welcome shift from the continuing resolutions and sequestration in recent years that has cut funding for important foreign investments.
There's a new CARE Package under the tree this holiday season.
ATLANTA (Nov. 21, 2013) — CARE USA hailed the introduction today of H.R. 3571, the International Violence Against Women Act (IVAWA), by Reps. Jan Schakowsky (D-IL), Nita Lowey (D-NY), Richard Hanna (R-NY), Eliot Engel (D-NY), Chris Gibson (R-NY) and Debbie Wasserman Schultz (D-FL). This bipartisan legislation aims to make ending gender-based violence (GBV) a top diplomatic priority of the United States.
ATLANTA (Nov. 13, 2013)—The global poverty-fighting organization CARE and its creative agency of record, Brunner, have brought back the iconic CARE Package® in a new ad campaign that debuts in November. The campaign recalls the origin of the CARE Package but through a contemporary lens that showcases the sustainable solutions to poverty that define CARE's work today.


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text: Publications Search Results Users may wish to consult What's Included in the Bibliography. Results 1 - 1 Results per page: 25 50 100 Sort by: Pub Date (newest) Title Recent Additions Author Clear All Pub. Year Citation 1995 Gazmararian, Julie A., James, Sherman A., Lepkowski, James M. Depression in Black and White women: The role of marriage and socioeconomic status. Annals of Epidemiology. 5, (6), 455-463. Full Text Options: DOI Worldcat Google Scholar Export Options: RIS EndNote XML [1]


text:
Graphics Cards
AMD FirePro V4800 & FirePro V7800
Last month we reviewed the ATI FirePro V8800, which is the newest ultra high-end workstation graphics card from AMD that is based upon the Evergreen graphics processor found in the consumer-grade Radeon HD 5000 series. We were blown away by the performance of the FirePro V8800 and then we subsequently reviewed the FirePro V3800 and FirePro V5800 when they launched later in the month. The FirePro V3800 was designed for entry-level workstation customers while the V5800 was to fill the mid-range void. For those looking into an entry-to-mid-range or high-end workstation graphics card, today we are completing our look at AMD's Evergreen-based FirePro family with a review of the ATI FirePro V4800 and ATI FirePro V7800.
17 May 2010 - 1 Comment
AMD Radeon HD 4290 On Linux
Last week we delivered benchmarks of the AMD Athlon II X3 425 processor running Ubuntu 10.04 LTS while this week we are continuing in benchmarks from this triple-core budget processor as we try out its gaming performance when paired with an AMD 890GX motherboard boasting integrated Radeon HD 4290 graphics.
5 May 2010 - 31 Comments
AMD FirePro V3800 & FirePro V5800
Earlier this month we reviewed the brand new ATI FirePro V8800 graphics card, which was AMD's first workstation graphics card based upon the Evergreen GPU refresh (derived from the consumer-grade Radeon HD 5000 series ASICs), and it was a magnificent performer. The FirePro V8800 played well with AMD's proprietary Linux driver and the OpenGL performance was terrific with sizable gains compared to AMD's previous ultra high-end workstation graphics card, the FirePro V8750, that was launched last year. The FirePro V8800 also introduced Eyefinity support and other features to the AMD workstation world. This morning AMD is expanding their selection of new FirePro products based upon the Evergreen architecture with the introduction of the FirePro V3800 and FirePro V5800, which are to address the entry-level and mid-range workstation segments, respectively. We have been testing out these new AMD FirePro graphics cards over the past week and have the Linux benchmarks to share.
26 April 2010 - 6 Comments
AMD FirePro V8800 2GB
Last week AMD launched the FirePro V8800, which is their first workstation graphics card derived from an ATI Evergreen graphics processor and designed to be a step-up from the previously reviewed FirePro V8700 and FirePro V8750. The AMD FirePro V8800 features 2GB of GDDR5 video memory with 147.2 GB/s of bandwidth, 1600 Stream processors, four DisplayPort outputs, ATI Eyefinity support, DirectX 11.0 / OpenGL 4.0 support, OpenCL 1.0 capable, a full 30-bit display pipeline, Multi-View display support, and much. We have now carried out our Linux testing of this new ultra high-end workstation graphics card and have the results to share this morning.
12 April 2010 - 28 Comments
Intel Atom: NVIDIA ION vs. Radeon HD 4330 Graphics
Last week we featured a review on two MSI WindBox Atom 330 NetTops that we had purchased to add to our testing farm, which as you may now know went into our Phoromatic Ubuntu Tracker setup that is monitoring the performance of the latest Ubuntu development packages on a daily basis. Before devoting this hardware to the farm, we ran a few benchmarks comparing the performance of NVIDIA's ION GeForce 9400M graphics processor to the ATI Radeon HD 4330 graphics processor found on the MSI 6667BB-004US and several other Atom-powered devices.
19 March 2010 - 53 Comments
Intel Clarkdale Linux Graphics Performance
Last week we delivered our first Linux benchmarks of Intel's Core i3 Clarkdale processor with a variety of computational tests through the Phoronix Test Suite. While the Core i3 packs a nice performance punch, that is not all it has to offer. Also found on the Clarkdale (and mobile Arrandale) processors is an integrated 45nm graphics processor that is supposed to offer a decent level of performance in comparison to earlier Intel IGPs normally found on the motherboard's Chipset. In this article are these first Intel benchmarks for the Clarkdale graphics processor as we see how its open-source Intel driver stack compares to that of AMD with their open-source Radeon stack up through the Radeon R700 series.
4 February 2010 - 27 Comments
ECS NVIDIA GeForce GT 240 512MB
A month after NVIDIA launched the GeForce GT 220 graphics card they rolled out the GeForce GT 240, to further fill the performance void between the GT216-based GT 220 and the GeForce GTS 250 that had been around since March. The $100 GeForce GT 240 has received some praise for its low-power consumption while delivering a decent level of performance for being a mid-range graphics card, but of course, those reviews have been when tested under Microsoft Windows. We finally have our hands on a GeForce GT 240 graphics card from the folks over at ECS Elitegroup to see how this GT215 graphics card performs under Linux.
22 January 2010 - 23 Comments
NVIDIA GeForce GT 220
Days prior to AMD's release of the ATI Radeon HD 5750 and Radeon HD 5770 graphics cards, NVIDIA released their GeForce G 210 and GeForce GT 220 graphics cards. Both of these NVIDIA graphics cards are for low-end desktop systems, but part of what makes them interesting is that they are the first NVIDIA GPUs built upon a TSMC 40nm process. To Linux users these graphics cards are also interesting in that they fully support all of the current features of VDPAU for Linux video decoding, including MPEG-4 support. We picked up an XFX GT220XZNF2 GeForce GT 220 1GB graphics card for this round of benchmarking on Ubuntu Linux.
19 October 2009 - 86 Comments
More AMD Radeon 5770 Linux Benchmarks
Earlier this week AMD launched the Radeon HD 5700 series GPUs using their Juniper GPUs as part of the Evergreen family. We published Linux benchmarks of the Radeon HD 5750/5770 on Tuesday with our thoughts on these new mid-range graphics cards, but today there are a few more Ubuntu results to add in for these ATI graphics cards.
16 October 2009 - 8 Comments
AMD Radeon HD 5750/5770
In late September AMD had introduced the Radeon HD 5850 and Radeon HD 5870 graphics cards as the successors to the Radeon HD 4850 and Radeon HD 4870, respectively. These graphics cards, which are part of the Evergreen GPU family, have been performing quite nicely according to reports, but we have yet to test either of these Cypress graphics cards under Linux. Today though AMD is introducing the first midrange graphics cards in the Evergreen family. Under the Juniper codename, the Radeon HD 5750 and HD 5770 are being launched with both graphics cards being quite similar except for the ATI Radeon HD 5770 shipping with slightly higher core and memory clocks along with a different heatsink. In this review we have the first Linux-based benchmarks of these two new graphics cards, which are also the first publicized Linux benchmarks from any AMD Evergreen graphics processor.
13 October 2009 - 281 Comments
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Results 1 to 10 of 21
Style: BJJ, formerly Judo--
Help with a second style.
I'm a reasonably competent judoka, nothing special, but passable. And I've done a wee bit of BJJ over the years.
Anyway, I'm looking to expand to a second style.
My first choice would be Kyokushin, but there's one school and it's on the same time as my judo class, so I was wondering about sparring in these styles, in general.
Shorinji Kempo,
Daito-Ryu Aikijujitsu (I did this for a little bit, but not enough to have any real knowledge).
More specifically I'm wondering:
How frequently does sparring occur? (Bearing in mind differences between schools)
How live is this sparring? (Point, Semi, or Full/Knockdown)
Effective? (By this I mean pragmatic boxing vs Reverse Thrust/Lunge Punch)
If none of these work, I may just start going to judo 5 days a week, or take up BJJ again. Or maybe Kendo, I'm not sure.
Style: BJJ, formerly Judo--
Fair enough. I'm looking for a striking based art which will work. I've done Wing Chun for four years and believed all the hype. I was a Larper as I think you people here refer to.
Long story short, I was rudely awoken, and now I just want a place where I can learn to strike, preferably through some sort of live sparring system. I'm not looking to kick ass, but I'm looking to train myself out of past habits (Pulling punches, leaving the head unprotected, basically everything wing chun taught me) as they've gotten me into serious trouble.
I'm not really lookiing for philosophy or culture lessons. No disrespect to anyone who likes that stuff, I just don't prioritise it.
I assume someone will say "join a boxing gym", but boxing isn't cheap around here, at all. So I'm just wondering, of those I specified is more martial, less art.
Thanks in advance.
Senior Member
- Join Date
- Jun 2008
- Location
- Long Island
- Posts
- 1,545
Posted On:
7/30/2008 12:21am
Style: Shotokan/Shorin Ryu--Originally Posted by hoodedmonk
I think you will like shotokan its a very straight forward linear hard style and you can find Shotokan almost anywhere. They too do alot of Kata but spar as well. Some schools spar more than others. You will have to check it.
Kyokushin is a rough ass style , they are hard core
Registered Member
- Join Date
- Jul 2005
- Location
- Brooklyn, NY
- Posts
- 875
Posted On:
7/30/2008 2:31pm
Registered Member
- Join Date
- Aug 2007
- Location
- Dallas
- Posts
- 928
Posted On:
7/30/2008 2:39pm
Style: MMA--
I would say shotokan by default, but you might want to check out each school first as every one is different. At my school we sparred very very often as a regular part of training, but this might not carry over into every school."This is why we are here. Because the Martial Arts for too long have been cloaked in an unnecessary level of secrecy bordering on mysticism, and its in these shadows that the cockroaches love to hide. -Phrost"
Originally Posted by Squerlli


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Jill Dando Institute of Crime Science
- Home Page
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JDiBrief - bitesize briefing notes on crime, security and analysis
What Works Masterclass: Problem solving and implementing evidence-based responses
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UCL JDI Centre for the Forensic Sciences
The Jill Dando Institute Centre for the Forensic Sciences is a new initiative at University College London. Its mission is to contribute significantly to the development of the forensic sciences through high quality multidisciplinary research, teaching & learning, and through the establishment of collaborative projects with external partners.
In September 2012 UCL is offering a new taught MSc in Crime and Forensic Science,
which offers students the opportunity to learn the scientific
behind forensic science within a crime science framework, and how these
are interpreted in the courtroom. Modules are being offered by the
departments of Security and Crime Science, Laws, Biosciences, Chemistry, Archaeology, Psychology and Computer Science - enabling students to
specialise in a particular area of forensic science if they wish.
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S48 - Trolver Barn
from £120 /night help Price for guests, Nights approx:
from £120 /night help Price for guests, Nights approx:
Estimated nightly price based on a weekly stay. Contact the advertiser to confirm the total cost.
Cottage / 4 bedrooms / sleeps 8
Availability Your dates are available
Cottage / 4 bedrooms / sleeps 8
|Key Info
� in unspoilt countryside on the edge of Feock, close to the creekside hamlet of Penpol and with easy access to a labyrinth of footpaths, a magnificent, split-level, 300-year-old, detached house with views of Restronguet Creek. Converted from a cattle barn and renovated with care and attention to detail. Suntrap garden with lawn and flower beds; two patios (tables/chairs, barbecue), one with creek view for alfresco dining and evening sunsets.
Inside, large, light, comfortable, triple-aspect living/dining room with wood floor (rugs), beams, woodburner, original artwork, TV/DVD and lovely creek views; 2 steps up to elegant dining area with glazed door to small viewing area and gentle sloping path to garden and parking. Four steps up to fitted kitchen (dishwasher, microwave, fridge-freezer) with small breakfast bar; a double bedroom (5� bed) with far-reaching country views and en suite bathroom (suite with separate shower), and a twin overlooking the garden (limited clothes-hanging space).
Downstairs (stairgate), large light hall with slate floor; short passageway with French windows to patio and garden; two more twin bedrooms (one zip-linkable to 6� double) with French windows to cobbled courtyard; bathroom (suite with separate shower). From the hall, 3 steps up to shower-room (suite); large games room (TV, 6� pool/snooker table, table football, Wii, sofas); utility room (washing machine, heated drying rails, wine fridge) with hanging for coats/wetsuits and door to parking/garden.
An individual, contemporary and stylish house providing a spacious and warm home at any time of year. Equally suitable for walking (Penpol and the creek, 300 yards), birdwatching, sailing, exploring or just relaxing.
|Sleeps up to 8, 4 bedrooms
|Car advised
|Family friendly
|Great for children of all ages
|Pets welcome, No smoking at this property
Features and Facilities
|Log fire, Internet access, DVD player, Sea view
|Central heating, TV, Telephone, Games room
|Kettle, Toaster, Iron
|Dishwasher, Cooker, Microwave, Fridge, Freezer, Washing machine
|4 bedrooms, 3 bathrooms of which 3 Family bathrooms
|Double beds (2), Single beds (4), Cots (1)
|Towels provided, High chair
|Secure parking
|Further details indoors
Please bring your own beach towels.
The agent has its own star rating system to quantify interior quality, comfort and ambience. This property has been rated 4 star.
The Cornwall region
Cornwall�s �Med�: here is Cornwall at its warmest, most sheltered; of creeks and tidal waters penetrating deep inland, deep in woods, silent except for birdsong; of wonderful gardens growing things that live nowhere else outdoors in England (marvellous in rhododendron, camellia, magnolia time, from March to end of May especially); of sailing boats everywhere decorating the sea; of harbour villages where the light is Mediterranean - dazzling in the sunshine. And really very little that is ugly has been allowed to be built.
Here is Truro, Cornwall�s (small) capital, with its 20th century cathedral; Falmouth, resort town and cargo/cruise ship/yacht port, superbly sited; and the glorious Helford River. Trewithen, Trelissick, Glendurgan, Trebah, Heligan (Lost Gardens of) and Caerhays are among the finest gardens. In the very middle of Cornwall, Lanhydrock house is very special, so is its garden. Not the greatest area for beaches, but good sandy ones near Veryan and Portscatho, in St Mawes, and around Falmouth and the Helford River�s mouth. Not to be missed is St Just-in-Roseland�s churchyard; nor - within easy reach - is The Eden Project (see South Cornwall).
Feock: sprawling village (church) almost hidden in trees, eyeing lazily an extensive estuary with creeks and open sea beyond. Boats/yachts on sheltered water, shingle beach for launching dinghies; sailing/windsurfing/canoeing lessons; beach caf�. Golf nearby. Trelissick Gardens (Nat. Trust) and the King Harry Ferry to the Roseland Peninsula. Creek-side walks. Truro (cathedral city), 5 miles. Falmouth, 7.
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16 Aug 2013
"What a fantastic place!!"
We have just returned from 2 magical weeks at Trolver Barn! It is an absolutely wonderful setting; so close to Truro & Falmouth yet so quiet and peaceful. We were a family of 4 for a week and were the… More
Thank you so much for your kind comments, I am so glad that you enjoyed your time at Trolver Barn. I hope we will see you again in the future.
14 Nov 2012
"Perfect accommodation, great location, fantastic facilities."
Perfect place for a west country holiday in a really lovely barn conversion. The standard of accommodation is of the highest level, with a wood burner for winter nights, comfy bed rooms and well finis… More
Thanks for taking time to leave your kind comments. We're delighted you had such a good holiday at Trolver Barn. It's certainly a lovely part of Cornwall to explore. We hope we can help you with your holiday plans again in the near future.
Best wishes
Helpful Holidays
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Former Delhi Chief Minister Arvind Kejriwal was on Monday directed by a court in New Delhi to "positively appear" before it on May 21 in connection with a criminal defamation complaint filed against him by BJP leader Nitin Gadkari.
The court's observation came after Mr. Kejriwal, who was summoned for Monday as an accused, did not appear before it on the ground that he was busy in campaigning for the Lok Sabha elections.
"The accused (Mr. Kejriwal) is directed to positively appear before the court on May 21," Metropolitan Magistrate Gomati Manocha said, while allowing the plea filed by Mr. Kejriwal's lawyer seeking exemption from personal appearance for the day for the Aam Aadmi Party (AAP) leader.
During the hearing, the counsel appearing for Mr. Gadkari, opposed the plea filed by Mr. Kejriwal's counsel saying the AAP leader should have appeared before the court on Monday.
The court, however, posted the matter for May 21.
The court, on February 28, had summoned Mr. Kejriwal as an accused in the criminal defamation complaint observing that statements allegedly made by the AAP leader have the effect of "harming the reputation" of the complainant.
The summon was issued against Mr. Kejriwal on a complaint in which Mr. Gadkari had alleged that he was defamed by Mr. Kejriwal, who had included his name in the party's list of "India's most corrupt".
Former BJP president Mr. Gadkari had said on January 31, 2014, that Mr. Kejriwal had issued a list of alleged "India's most corrupt" in which he had named various politicians, including him.
On January 31, Mr. Kejriwal had accused several politicians of being "corrupt" and had said AAP will field candidates against them in coming Lok Sabha polls.


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Kochi, Sep 18 (IANS) The month of Ramadan is a dull period for Malayalam cinema as collections dip and theatres close for annual maintenance. With no new releases for the next few weeks, Mohanlal starrer 'Ore Kadal' tops the chart.
The top five Malayalam films are:
1. 'Ore Kadal' - Mammootty has the knack of maintaining a balance between commercial and off beat films. Directed by Shyama Prasad, 'Ore Kadal' is a well-told, delicate story about a housewife, played by Meera Jasmine, falling in love with a self-absorbed social scientist.
2. 'Alibhai' - The film continues the lean patch in megastar Mohanlal's career. Directed by Shaji Kailas has used all the ingredients that Mohanlal fans enjoy watching in his films, but it didn't work at the box office.
3. 'Arabikatha' - Sreenivasan and director Lal Jose make a film about the Left in Kerala. Laced with humour, it hits the nail on the head.
4. 'Hello' - Director Rafi-Mecartin's film is a saving grace for Mohanlal. Released long before Onam, it gave the fans of the star something to cheer about, as it is one of the biggest hits of the year.
5. 'Indrajith' - A typical Kalabhavan Mani film directed by Haridas, the film was released just a week before Ramadan and made it to the list as there is no other film vying for the place.
Do you like this article?
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|o|oNaTaShAo|o, -Believe-
classy movie..from shyam
great article .....thx for sharing
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Swimmers Attempt Record In Race Around Manhattan
All four were attempting to beat the record of 5 hours, 45 minutes, 25 seconds set by Shelley Taylor-Smith in 1995.
NYC Group Touts Benefits Of Running Barefoot
City sidewalks in the summer can be hot, crowded and covered with grime. Most people don't want their shoes to touch the stuff on the streets — never mind their bare feet.
Go New York!: Running The City
Alfatah Kadal claims he runs the City, and with no disrespect to Mayor Bloomberg, he really does.


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Safe Harbor This release may contain certain forward-looking statements regarding our prospective performance and strategies within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. We intend such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995, and are including this statement for purposes of said safe harbor provisions.
Forward-looking statements, which are based on certain assumptions and describe future plans, strategies, and expectations of our company, are generally identified by use of words "anticipate," "believe," "estimate," "expect," "intend," "plan," "project," "seek," "strive," "try," or future or conditional verbs such as "could," "may," "should," "will," "would," or similar expressions. Our ability to predict results or the actual effects of our plans or strategies is inherently uncertain. Accordingly, actual results may differ materially from anticipated results. Some of the factors that could cause our actual results to differ from our expectations or beliefs include, without limitation: the unpredictability of the size of the markets for, and market acceptance of, any of our products, including the Keyhole Cup Laparoscopic Access Device; our ability to produce and sell any approved products and the price we are able realize for those products; ourability to enter into a
|SOURCE Life Care Medical Devices Ltd
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Bad News UCF And USF – No Big XII Expansion Any Time Soon
Here is the latest on the chance that the Big XII might expand to 12 teams. According to our sources as well as a number of media reports the conference will not be looking for any new members. There
Video: World Series Game 6 Has Had Plenty Of Memories
Tonight 8:00 p.m.ET it will be World Series Game 6 between the San Francisco Giants and the Royals at Kauffman Stadium in Kansas City, on FOX. The Giants hold a 3 games to 2 lead over the Royals and
10 College Football Games Not To Be Missed
As a public service we at Sports Talk Florida do not want you to waste a moment of your weekend watching bad football. So, in the interest of making sure that Saturday brings you nothing but quality football action,
NFL: Network TV Coverage 2014
Each year brings us something new to look out for when we plan our NFL TV viewing and this year is no different. FOX, CBS, NBC, ESPN and the NFL Network all have made changes to their talent rosters
MLB, FOX Release Statement On Tony Gwynn Matter
Seeing as how there was no baseball yesterday, the news that MLB on FOX released a joint statement
STF talks with Joe Buck on his new FOX MLB team
Yesterday FOX made it official lead announcer Joe Buck will be joined in the broadcast booth by Harold Reynolds and Sports Illustrated senior writer Tom Verducci. For Buck, who was born in St. Petersburg, this is the first year since 1996
NASCAR: The big boys head west for a desert showdown
Here are some of the fast facts about this weeks big race in Phoenix. Date: Sunday, March 2 Start Time: 3 p.m. ET Site: Phoenix International Raceway — Avondale, Ariz. Track: 1-mile oval Laps: 312 Miles: 312 (500 kilometers) TV: FOX On Radio: Motor Racing Network
Super Bowl XLVII Sets Ratings Record- Bay Area Rating Is Huge
Super Bowl XLVII might have been a blowout win for Seattle over Denver but over 111.5 million people watched the game, more than any television program in U.S. history. The Tampa Bay market ranked an impressive 10th overall in all the
The real Super Bowl Showdown: Obama vs O'Reilly
Well we know that the Denver Broncos and the Seattle Seahawks should put on one heck of a show come Sunday night in New Jersey. However, from an entertainment value you might want to tune in on Fox
ELOOnline : Super Bowl TV Coverage Preview
Eric Lopez talks to James Williams about Fox's Super Bowl 48 broadcast plans.


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¡Gracias! Su mensaje ha sido enviado correctamente
Síbelgroup, is a group of companies formed by Sibelmed, Asimed, Bitmed, dedicated to the manufacture and sale of medical equipment such as spirometers, audiometers, audiometric booths, polygraphs, polysomnographs and weighing scales.
If you want your company to become part of a group with a long experience in the industry over 35 years and a reputation based on our professionalism, innovation and quality, contact us and our team will inform you about everything that precises.
26-29 January, Dubai – EEAA
Sleep course Dr. Terán
4-7 May, Burgos · Spain
5-8 June, Canarias · Spain
16-19 November, Düsseldorf · Germany


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Choiseul Hotel Reviews
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Reviews & Ratings Explained
The rating percentage is calculated from customers who booked within the last 12 months.
All ratings and reviews are based on the feedback and opinions of the customers who submitted them and do not express the opinions of Hostelworld.com. This way, you get an up-to-the-minute opinion of just how good a hostel really is.
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Staff and management very helpful and friendly - hotel clean, central and good value
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A very inexpensive hostel which was in a great location in Bordeaux. Hostel staff was very friendly and welcoming. Room was a bit small, and I didn't have a private toilet or shower in my room, but nonetheless was a good room/experience. Very good for the price.
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Magnetic resonance angiography (MRA) is a technique for imaging vascular anatomy and pathology that does not use ionizing radiation. MRA is performed using magnetic resonance imaging (MRI) machines, and vascular images may be generated either with or without intravenous contrast agents, depending on the clinical application. However, the contrast agents used for MRA are associated with less risk of allergic reaction or nephrotoxicity than those used for conventional angiography.
MRA is the general term used to describe MRI of vascular structures, but when MRI is used to image a vein instead of an artery, the term magnetic resonance venography (MRV) may be used.
The technical capabilities of current MRA make it most suitable for evaluation of medium to large size vessels. In the head, this includes the Circle of Willis and major posterior circulation vessels, while in the body this includes the aorta and its major arterial branches such as renal, hepatic and mesenteric arteries. MRA is less suitable for providing detailed information about the small peripheral vasculature.
MRA application in the thorax (chest) can be subdivided into the following categories:
Each benefit plan, summary plan description or contract defines which services are covered, which services are excluded, and which services are subject to dollar caps or other limitations, conditions or exclusions. Members and their providers have the responsibility for consulting the member's benefit plan, summary plan description or contract to determine if there are any exclusions or other benefit limitations applicable to this service or supply. If there is a discrepancy between a Medical Policy and a member's benefit plan, summary plan description or contract, the benefit plan, summary plan description or contract will govern.
Blue Cross and Blue Shield of Montana (BCBSMT) may consider magnetic resonance angiography (MRA) and venography (MRV)eligible for coverage when specific criteria outlined below are met:
MRA of the Head:
MRA of the head may be considered medically necessary for the assessment of patients with:
MRA of the Neck:
MRA of the neck may be considered medically necessary in the assessment of patients suspected of having:
MRA of the Abdomen or Pelvis:
MRA of the abdomen or pelvis may be considered medically necessary for the assessment of patients with the following clinical indications, in whom angiography would otherwise be indicated, and in whom the result of the MRA would eliminate the need for standard contrast angiography:
MRA of the Pelvis or Lower Extremities:
MRA of the pelvis or lower extremities may be considered medically necessary for the assessment of patients with:
MRA of Potential Renal Donors:
MRA of potential renal donors may be considered medically necessary to evaluate the presence of accessory renal arteries.
MRA of the Chest (Excluding the Heart):
MRA of the chest (excluding the heart) may be considered medically necessary for patients with any of the following:
MRA of the chest (excluding the heart) is considered not medically necessary for any other condition not listed above.
MRA of the Heart:
MRA of the heart may be considered medically necessary in patients who have a history of severe contrast media allergy to iodine contrast or who are at high risk of contrast-induced renal failure, such as in diabetic patients with moderate renal insufficiency, and in patients for the following:
MRA of the heart is considered not medically necessary for:
MRA of the Spinal Canal:
MRA of the spinal canal is considered experimental, investigational and unproven for any condition.
MRV of the Head:
MRV of the head may be considered medically necessary for the evaluation of patients:
MRV of the Chest or Abdomen:
MRV of the chest or abdomen may be considered medically necessary for the evaluation of patients suspected of having:
This policy is based on a series of Blue Cross Blue Shield Association (BCBSA) Technology Evaluation Center (TEC) Assessments in 1997, which focused on MRA of the head, neck and abdomen. (1-7), as well as additional information on MRA of the pelvis and lower extremities as a technique to evaluate peripheral vascular disease and MRA of the abdomen for evaluation of potential living renal donors available as of 2003.
MRA of the pelvis and lower extremities has emerged as an important tool for surgical planning, particularly to identify patent run-off vessels when surgical revascularization is considered. (8-11) In addition, MRA has been widely used to evaluate the recurrent symptoms in patients who have undergone either angioplasty or surgical revascularization. A meta-analysis of 34 studies, conducted by Koelemay et al., (12) found that MRA was accurate for identifying stenosis (>50%) or occlusions in the aortic-iliac, femoropopliteal, and infrapopliteal regions. Baum et al. (13) found that MRA is more sensitive for identifying run-off vessels compared with conventional angiography. Use of vessels visible only on MRA for bypass surgery provides an opportunity for limb salvage and when compared with bypass to angiographically, visible vessels, graft-patency and limb-salvage outcomes are similar. (14) These roles of MRA are recognized by the ACR (American College of Radiology) Appropriateness Criteria, found in the ACR Practice Guidelines. (15-16)
Diagnostic performance of MRA of the abdomen for evaluation of renal anatomy in potential living renal donors has improved with the evolution of contrast-enhanced MRA techniques. Recent studies have shown contrast-enhanced MRA to have good sensitivity and specificity for detection of renal arterial and venous anomalies. Three studies reported sensitivity and specificity of 90% or higher for renal arterial anatomy. (17-19) One study examined the ability of contrast-enhanced MRA to detect arterial, venous, ureteral, or parenchymal anomalies during the presurgical evaluation process for laparoscopic nephrectomy. (20) This study found that preoperative MRA agreed completely with surgical findings in 21 of 28 cases (75%). In this study, the laparoscopic surgical procedure was successful in 27 of 28 cases (96%) and only one case required conversion to open nephrectomy, suggesting that some oversights on MRA may not be clinically significant. Furthermore, studies comparing contrast-enhanced MRA to alternatives such as computed tomographic (CT) angiography (CTA) and digital subtraction angiography have reported comparable results. (21-22) However, concerns have been raised regarding the ability of MRA or CTA to detect mild or distal-moderate fibromuscular dysphasia that can be seen on conventional renal angiography. (24) The prevalence of fibromuscular dysphasia is about 2% to 6.6% in angiographic case series, and it is unclear what effect donor nephrectomy may have on the subsequent development of hypertension in asymptomatic potential renal donors who have silent fibromuscular dysphasia. (24)
Additionally, in the initial policy review using the same series of 1997 BCBSA TEC assessments (1-7) indicated earlier, our conclusion was that, compared to angiography, MRA provides:
However, the evaluation also concluded that diagnostic performance is not sufficiently accurate to allow replacement of pulmonary angiography in the diagnosis of pulmonary embolism (PE) in patients who have no contraindications to receiving intravenous iodinated contrast material. In this setting, MRA may be an acceptable alternative to angiography in patients who are allergic to or who have other contraindications (e.g., renal insufficiency) for iodinated contrast media. (1-7)
It should be noted that in all applications, MRA is considered an alternative to angiography. A 2003 review did not identify any published articles that addressed the limitations noted in the series of BCBSA TEC Assessments; therefore, the policy statement is unchanged. Specifically, the appropriateness criteria of the ACR are consistent with the conclusions of the BCBSA TEC Assessment. For example, the ACR appropriateness criteria offer the following statement regarding MRA in a patient with suspected PE, "MRA is not indicated in the routine evaluation of patients with suspected pulmonary embolism…currently it is mainly used in certain centers with particular interest and expertise, and in patients in whom contrast administered for helical CT scans or even for pulmonary angiography is thought to be contraindicated.…" (15-16)
2006 Update
Literature was searched for the period of 2003 through March 2006, with a particular focus on MRA of the chest to detect PE and on MRA of the heart. MRA would only be indicated in the subset of patients that have a contraindication to contrast media containing iodine. When indicated, the administration of intravenous MRI or MRA contrast agent (Gadolinium chelate) is associated with an overall lower nephrotoxicity and allergic response when compared with radiographic use of intravascular iodinated contrast material during CT examinations. Contrast utilization is at the discretion of the ordering and imaging providers. (16)
2008 Update
A literature search of MedLine database was performed through August 2008. No articles were identified that would change the coverage position of this medical policy.
2010 Update
A search of peer reviewed literature through September 2010 identified no new clinical trial publications or any additional information that would change the coverage position of this medical policy.
2012 Update
A search of peer reviewed literature through June 2012, including a review of the current ACR Appropriateness Criteria, found in the ACR Practice Guidelines (25-27), identified no new clinical trial publications or any additional information, that would change the coverage position of this medical policy.
Disclaimer for coding information on Medical Policies
Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.
The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.
Benefit coverage determinations based on written Medical Policy coverage positions must include review of the member's benefit contract or Summary Plan Description (SPD) for defined coverage vs. non-coverage, benefit exclusions, and benefit limitations such as dollar or duration caps.
Refer to the ICD-9-CM manual.
Refer to the ICD-10-CM manual.


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50 - 100 downloadsAdd this app to your listsTweets por @Appszoom
Chick-fil-A Bowl ACC & SEC Pocket Schedule: The Chick-fil-A Bowl, host of the original ACC vs SEC match-up, brings you the entire 2013 ACC and SEC football season schedule in one place. You can sort the schedule by conference, team, game week and Broadcast TV network. In addition, receive comprehensive updates on TV network changes, game times, final scores, conference standings and national rankings. Play and share our weekly and season-long Pick'em game for free Chick-fil-A food and prizes.
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