 to give a physical definition of the straight line, though in our theory there is no object or process modeling the straight line, like a light beam in ordinary relativity theory". In other words, they stated that the existence of conservation laws implies the flat Minkowski geometry. In the same article Einstein and Grossmann also emphasized that the gravity field must have an energy-momentum tensor as all other physical fields. However, in the final version of general relativity Einstein rejected this requirement in order to have a generally covariant gravity theory with no prior Minkowski geometry" [20]. "As it was noted 90 years ago by Hilbert (1917), Einstein (1918), Schrodinger (1918) and Bauer (1918) within Geometrical Gravity approach (General Relativity) there is no tensor characteristics of the energy-momentum for the gravity field" [20]. 14 In General Relativity, gravity was geometrized As in General Relativity is impossible to obtain a tensor for the energy and momentum of the gravitational field which satisfies the double condition: 1. When added to other forms of energy the sum is conserved, 2. It is independent of coordinate systems, Instead, Einstein constructed a pseudo tensor for satisfy only the condition that the sum is conserved; too other physicists have obtained similar pseudo tensors but the problem is that pseudo tensors behave only as tensors with respect to linear transformations of frames of reference, i.e, pseudo tensors are not general covariant. A notable example is the Landau–Lifshitz pseudo tensor. Although quite confused about relativity, José Ortega y Gasset was right when, perhaps with the intuition of an intellectual a little of fortune teller or by the influence of his close physicist friends, in 1923, in the visit of Einstein to Spain he said him "You will end up making physics a geometry" [23] and most of its current followers say: "Einstein geometrized gravity". "Can we extend the Principle of Relativity to accelerated reference frames? That is, can acceleration be made relative? Can we incorporate gravity into Special Relativity? That is, can it extend the "laws of physics" in the Principle of Relativity to include Newton's Law of Gravity? Einstein's solution to both: Geometricize the gravitational force: turn it into a manifestation of spacetime curvature" [24]. "The key idea of Einstein's theory of general relativity is that gravity is not an ordinary force, but rather a property of space-time geometry. In Einstein's theory of general relativity, gravity is a distortion of
to give a physical definition of the straight line, though in our hypothesis there be no object or process model the true line, like a light balance beam in average relativity theory ". In other words, they stated that the existence of conservation law implies the flat Minkowski geometry. In the like article Einstein and Grossmann also emphasized that the gravity field must have an energy - momentum tensor as all other forcible fields. However, in the final version of cosmopolitan relativity Einstein rejected this requirement in order to have a generally covariant gravity hypothesis with no prior Minkowski geometry " [ 20 ]. " As it was note 90 years ago by Hilbert (1917), Einstein (1918), Schrodinger (1918) and Bauer (1918) within Geometrical Gravity approach (General Relativity) there is no tensor characteristic of the energy - momentum for the gravity field " [ 20 ]. 14 In General Relativity, gravity was geometrized As in General Relativity is impossible to obtain a tensor for the energy and momentum of the gravitational field which satisfies the double condition: 1. When added to other forms of energy the sum is conserved, 2. It is independent of coordinate organization, Instead, Einstein constructed a imposter tensor for satisfy merely the circumstance that the sum is conserved; too other physicists have obtained similar pseudo tensor but the problem is that pseudo tensors behave only as tensors with obedience to linear transformations of frames of reference, i.e, pseudo tensors are not general covariant. A noteworthy example is the Landau – Lifshitz pseudo tensor. Although quite confused about relativity, José Ortega y Gasset was right when, perhaps with the intuition of an intellectual a short of fortune teller or by the influence of his close physicist acquaintance, in 1923, in the visit of Einstein to Spain he said him " You will end up making physics a geometry " [ 23 ] and most of its current follower say: " Einstein geometrized gravity ". " Can we gallop the Principle of Relativity to accelerated mention frames? That is, can acceleration be reach relative? Can we integrate gravity into Special Relativity? That is, can it extend the " laws of purgative " in the Principle of Relativity to include Newton's Law of Gravity? Einstein's solution to both: Geometricize the gravitational force: turn it into a manifestation of spacetime curvature " [ 24 ]. " The key idea of Einstein's theory of general relativity is that gravity is not an ordinary force, but rather a place of space - time geometry. In Einstein's hypothesis of general relativity, gravity is a distortion of
 to give a physical definitlon of the straiyyt linx, thougg in our theory there is no object oc pricess modeling the straight line, likv a light bean in ordinacg relatlrity fmeory". Mn other words, jhey stated dhat the existanze of conservation laws implies the fjat Minloaski geometry. Yn tnq sajv crticle Einstein and Grossmann zlso emkhasized that the bravity field must have an eneggy-momentum tensor as all othgd prtsical fieldr. However, pu the final version of general relativity Dinstzin rejectee rhid requiremenv in ogder to have a generanly covsriant gravity thxory with no prior Minkowvki geometry" [20]. "As ij was noteg 90 years ago by Hilveet (1917), Ehnstain (1918), Wchfodjnjer (1918) and Hauxr (1918) within Feometrical Gravity approach (Gtnewql Relativity) there if no tensor characteristics of the enercy-mkmentum for the gravity field" [20]. 14 In General Rglativity, dravity was geometrized As in General Relativity hs im'orsiyoe to ibhain a tensor for the energy and momentum of ege ggavitational fielb which satisfiex hhr double condijion: 1. Wksn added to other fogms of gnergy the sum ys cpnserved, 2. It is independent of coordinane ststems, Instead, Eindtein constxucted a psrudo tensor for satisfy onlg the condihion that ghe sum is consefvec; doo other physicists have jbtained wimikar psejdo jensors but the pgoblem is that pseudo tejsors bahave only as tensors with respect to linxer transformajiots mf framef of veference, i.e, psqudo tensors ate not geueral zovariant. Z notabne example ys the Landau–Nlfshitz pseuvo tensor. Altyougy quite zonfused about relativiny, José Ortega y Gasset wes rkfht when, perhapw wuth the intuitipn uf wn iitellqwtual a littne ow futtune teller or ny ghe onfluence of his clove pgysicist friends, im 1923, in the cisit of Einstein to Xpain he said him "Jou wmll env up mskigg physics a geometry" [23] and mosf of its furvent followerf san: "Eigstein geoketrized gravity". "Can we extend the Prinriple of Relativity to qccelerated referenee frames? Thav is, cwn accelesation be made relatuve? Can we incorpprate gravity into Spscial Selatlvity? That is, can it extend the "laws of physics" in the Principle of Relatuvity vo include Neston'x Law oy Gxavity? Qinsvemn's solution to bpth: Geometricize the gravitatioial force: duxn it into a manifestation of soacetime curvxture" [24]. "The key idea of Ejnstein's theory of general relativity ix that gravity is not an ordinart forde, but ratier a property of spsce-timz geomwtry. In Eindtein's theory of gcneral relwtivmty, gravity is a distortion of
to give a physical definition of the though our theory is no object line, a light beam ordinary relativity theory". other words, they stated that the of conservation laws implies the flat Minkowski geometry. In the same article Einstein Grossmann also emphasized that the gravity field must have an energy-momentum tensor as other fields. in final version of general relativity Einstein rejected this requirement in order to have a generally covariant theory with no prior Minkowski geometry" [20]. "As was noted 90 years by Hilbert (1917), Einstein (1918), (1918) Bauer (1918) Geometrical approach Relativity) there is tensor characteristics of the energy-momentum for the gravity field" [20]. 14 In General Relativity, gravity was geometrized in General impossible to a for energy and momentum gravitational field which satisfies the double added to other forms of energy the sum conserved, 2. is independent of coordinate systems, Instead, constructed a pseudo tensor for satisfy only the that the sum is conserved; too other physicists have obtained similar pseudo tensors but the that pseudo tensors behave as tensors with to transformations frames reference, i.e, tensors are not general covariant. A notable example is the Landau–Lifshitz tensor. Although quite confused about relativity, José Ortega y Gasset when, with the intuition an intellectual a little fortune or by the influence close friends, the of to Spain he said "You will end up making a geometry" [23] and say: "Einstein geometrized gravity". "Can we extend the of Relativity to accelerated reference frames? That can acceleration be made relative? Can we incorporate gravity into Special Relativity? is, can the "laws of physics" in the Principle of to include Newton's Law Gravity? Einstein's solution to both: Geometricize the gravitational force: it a manifestation spacetime curvature" [24]. key idea of theory of general that gravity not ordinary a property of space-time geometry. In theory general relativity, gravity is a of
 to give a physical definition Of the straiGht liNe, tHouGh In ouR theOry there is no obJEct oR process modeling the strAight LiNE, likE A lIght bEam in orDInARY reLaTiVitY tHEoRy". In oTheR words, tHey stated tHat ThE existence of COnServation lAws Implies the flAt MInkowsKi GeoMEtry. IN thE same ArticlE einsteIn and GrosSmANn also EMphasizED ThAt thE gravity field must HAvE An energy-momentUm tensOr AS aLL OthEr pHysical fieLdS. HoweVEr, in the FInAL VErsIOn of general reLativity EinSTeiN rejecTeD thIS requiRemenT iN OrdEr to have a geNeraLly covariAnt graVIty theoRY with no Prior MInkOwsKi geOMeTrY" [20]. "As It WAs nOTeD 90 yeARs aGo by HilbErT (1917), EInsteIn (1918), ScHRODIngeR (1918) anD BauEr (1918) witHin GeometricaL GrAvitY AppRoach (generAl ReLaTivitY) there Is no tEnSor characteristIcs oF the energY-moMeNtuM fOr the GRavity FieLd" [20]. 14 IN GeneraL RelatiVIty, GrAVITy Was geometrized As in geNERaL RelativIty is iMPoSsIBle to obtAiN a tEnsoR FOr the EnerGY aNd momentUm of thE GrAvItationAl Field wHiCh sAtiSfies THe doUble coNdition: 1. WHen adDEd to other forms OF energy the sum IS cONSeRVed, 2. IT is Independent Of coORdinAte sYStEms, iNsteaD, EinsTeIN cONstructed a pseudo tenSoR for saTisfy Only the conditIon that the SUM Is conserVed; tOO oTHer physicists hAve obTained simiLAr pseudo TensoRs but the Problem is THAt pseudo TenSorS beHavE ONlY as tensors witH REspeCt To lineaR trAnsformAtiOns Of fRamEs Of referenCe, i.e, pseuDo TeNsOrS arE not gENeral covArIanT. A NotAble eXAmple iS the LAndaU–LIfSHitZ pseudo TEnSOR. AltHoUgH quiTe cOnFused AbouT RelAtivity, josé OrtegA y GASset WaS rIght wheN, perhaps with tHe Intuition oF aN inTellecTUAl a littlE of fortune teller or by the INfluencE of His clOse pHysicist fRieNds, in 1923, iN thE Visit oF EinstEin to spAin HE Said hIM "yoU wiLl End up makinG PHysIcs a gEoMetrY" [23] and mosT of its current folloWErs Say: "Einstein geOmeTrizED GrAviTY". "CAN we ExTEnd THE Principle of RelAtivity to aCcELeRated referENce FrAmes? ThaT is, can aCceleRAtion be Made relatIve? Can we iNcOrpoRATe gRavity into special RElativity? tHat is, CAn It extEnd The "lawS oF phYsics" In the PRIncIple oF RelatIvIty to iNcludE NEwton's LaW of Gravity? Einstein's soluTion to Both: GEomEtricize tHe gRAviTational fOrce: Turn it into A maNifEstatIon OF spacEtimE CuRvaTUre" [24]. "ThE key IDea of EinsTEiN's tHEOrY of general rELATivIty is ThaT GravitY is nOt an ordinary force, BUt rather a propeRty oF SPacE-tiME geoMeTry. In Einstein's TheOrY OF general ReLativity, graVity is a dIsTOrtioN of
 to give a physical defini tion of th e str aig htli ne,thou gh in our theo r y th ere is no object or pr ocess  m o deli n gthe s traight li n e , l ik ea l ig h tbeaminordinar y relativi tyth eory". In ot h er  words, th eystated thatthe  exist en ceo f con ser vatio n laws implie s the fla tM inkows k i geome t r y.  Inthe same articleE in s tein and Gross mann a ls o  e m p has ize d that the  g ravit y  fieldm us t h ave an energy-mom entum tenso r  as  all o th erp hysica l fie ld s . H owever, inthefinal ver sion o f  genera l  relati vity E ins tei n re j ec te d t hi s  re q ui rem e ntin order  t ohavea ge n e r a llycov aria nt gr avity theorywit h no pri or Mi nkows ki g eo metry " [20] . "As  i t was noted 90year s ago byHil be rt(1 917), Einste in(19 18), Sc hroding e r ( 19 1 8 )  a nd Bauer (1918) wi th i n  G eometric al Gra v it ya pproach(G ene ralR e lativ ity) th ere is n o tens o rch aracter is tics o fthe  en ergy- m omen tum fo r the gr avity field" [20]. 1 4  In General R e la t i vi t y, g rav ity was geo metr i zedAs i n  G ene r al Re lativ it y  i s  impossible to obta in  a ten sor f or the energy  and momen t u m  of thegrav i ta t ional field wh ich s atisfies t h e double  cond ition: 1 . When ad d e d to oth erfor msofe n er gy the sum is c onse rv ed, 2.Itis inde pen den t o f c oo rdinate s ystems,In st ea d,  Ei nstei n  constru ct edapse udo t e nsor f or sa tisf yon l y t he cond i ti o n  tha tth e su m i sconse rved ;  to o other  physicis tsh aveob ta ined si milar pseudote nsors butth e p roblem i s that p seudo tensors behave on l y as te nso rs wi th r espect to  li near t ran s format ions o f fra me s o f refer e n ce , i .e , pseudo t e n sor s are  n ot g eneralcovariant. A notab l e e xample is the  La ndau – L if shi t zp seu do ten s o r. Although qui te confuse da bo ut relativ i ty,  J osé Ort ega y G asset was rig ht when,perhaps w it h th e int uition ofan intel lectual a littl e  o f for tun e tell er  or  by t he inf l uen ce of  his c lo se phy sicis tfriends,  in 1923, in the visitof Ein stein  to  Spain he  sa i d h im "You w illend up mak ing  ph ysics  ag eomet ry"[ 23 ] a n d mos t of its curre n tfol l o we rs say: "Ei n s t ein  geom etr i zed gr avit y". "Can we exten d  the Principle  ofR e lat ivi t y to  a ccelerated ref ere nc e frames?Th at is, canaccelera ti o n bemade r elativ e? Canw e  i n corpor ategra vity into  Sp ec i al Rela ti vi t y? Tha t is ,can it  exten d  the " laws of physics"  in t h e  Prin c ipl e ofRe lativit y  toinclude Ne wton's Lawof Gra vity ? Ein stein's  s olutio n t oboth: Geom e tricize t he gr avitati on al f orc e: tur n it i nto a  man if est ation ofs p ac e ti me cur vatu re" [ 24 ]. " The key i d ea of Ei nst e in's th eo ryo f  gener a lr e lativity i s t hat g r a vity is no t  ano rd i naryforce,  but r ather a pro pe rty ofspa c e -time geo metry. In Ein st ein' s theory  o f ge ne ral  r elativity, grav ity is a  distort i o n of
 to_give a_physical definition of the_straight line,_though_in our_theory_there is no_object or process_modeling the straight line,_like a light_beam_in ordinary relativity theory". In other words, they stated that the existence of conservation_laws_implies the_flat_Minkowski_geometry. In the same article_Einstein and Grossmann also emphasized_that the_gravity field must have an energy-momentum tensor as_all_other physical fields._However, in the final version of general relativity Einstein_rejected this requirement in order to_have a generally_covariant_gravity_theory with no prior_Minkowski geometry" [20]. "As it was_noted 90 years ago by Hilbert_(1917), Einstein (1918), Schrodinger (1918) and Bauer_(1918) within Geometrical Gravity approach (General_Relativity) there is no tensor_characteristics of_the energy-momentum for the gravity_field" [20]. 14_In General_Relativity, gravity was_geometrized As in General Relativity is_impossible to obtain_a tensor for the energy and_momentum_of the gravitational_field_which_satisfies the_double condition: 1._When_added to_other_forms of energy the sum is_conserved,_2. It is independent of coordinate systems,_Instead, Einstein constructed a_pseudo_tensor for satisfy only_the condition that the sum_is conserved; too other physicists have_obtained similar_pseudo tensors_but the problem is that pseudo tensors behave only as tensors_with respect to linear transformations of_frames of reference, i.e,_pseudo tensors_are_not general covariant._A_notable example_is the Landau–Lifshitz pseudo tensor. Although quite_confused about_relativity, José Ortega y Gasset was_right when, perhaps with_the_intuition of an intellectual a little_of fortune teller or by the_influence of his close physicist_friends,_in_1923, in the visit of_Einstein to Spain he said him_"You will end_up making physics a geometry" [23] and_most_of its current followers say: "Einstein_geometrized_gravity". "Can we extend the Principle_of_Relativity_to accelerated reference frames? That_is, can acceleration be made relative?_Can we incorporate gravity into Special Relativity? That is,_can it extend_the "laws of physics" in_the_Principle_of Relativity to include Newton's Law of Gravity? Einstein's solution_to both:_Geometricize the gravitational_force: turn it into a manifestation of spacetime curvature" [24]._"The key idea of Einstein's theory of_general relativity is that gravity is not an ordinary force, but_rather a property of space-time geometry. In Einstein's_theory of general relativity, gravity is a_distortion of