Results for 'gravitational theories'

966 found
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  1. Evaluation of post-Einsteinian gravitational theories through parameterized post-Newtonian formalism.Nicolae Sfetcu - manuscript
    Right after the elaboration and success of general relativity (GR), alternative theories for gravity began to appear. In order to verify and classify all these theories, specific tests have been developed, based on self-consistency and on completeness. In the field of experimental gravity, one of the important applications is formalism. For the evaluation of gravity models, several sets of tests have been proposed. Parameterized post-Newtonian formalism considers approximations of Einstein's gravity equations by the lowest order deviations from Newton's (...)
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  2. Modern Tests of Relativistic Gravitational Theories.Nicolae Sfetcu - manuscript
    Dicke and Schiff established a framework for testing general relativity, including through null experiments and using the physics of space exploration, electronics and condensed matter, such as the Pound-Rebka experiment and laser interferometry. The gravitational lens tests and the temporal delay of light are highlighted by parameter γ of the PPN formalism, equal to 1 for general relativity and with different values in other theories. The BepiColombo mission aims to test the general theory of relativity by measuring the (...)
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  3. Tests and Anomalies of Post-Newtonian Gravitational Theories.Nicolae Sfetcu - manuscript
    Usually, the "laboratory" of gravitational tests was the celestial bodies, the astrophysical systems. But such tests are disturbed by non-gravitational effects. The most used such "laboratory" was the solar system. Recently, scientists have focused on observing binary pulsars for the verification of gravitational theories, by observing the variations of the orbital period, thus providing indirect evidence for the emission of gravitational radiation. But the experimenter cannot "arrange the lab" according to his needs, nor trigger certain (...)
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  4. Théorie des cordes, gravité quantique à boucles et éternalisme.Baptiste Le Bihan - 2021 - In Alexandre Declos & Claudine Tiercelin (eds.), La Métaphysique du Temps: Perspectives Contemporaines. Collège de France.
    L'éternalisme, la thèse selon laquelle les entités que nous catégorisons comme étant passées, présentes et futures existent tout autant, est la meilleure approche ontologique de l'existence temporelle qui soit en accord avec les théories de la relativité restreinte et de la relativité générale. Cependant, les théories de la relativité restreinte et générale ne sont pas fondamentales si bien que plusieurs programmes de recherche tentent de trouver une théorie plus fondamentale de la gravité quantique rassemblant tous les enseignements de la physique (...)
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  5. Theoretical mass value of electron, neutrino and other particles by means of QED together with Gravitational theory.Enrico Pier Giorgio Cadeddu - manuscript
    From time involved in pair production process, in the photon-photon collision, we consider energy and then mass uncertainty. Taking the latter as the mass of a particle, we repeat pair production process obtaining another mass uncertainty, then another particle mass, and so on. Starting with the heaviest charged elementary particle that is possible using Planck length for electromagnetic mass, we obtain a mass value close to electron mass. It is supposed exactly electron mass, considering the presence of uncertainties in the (...)
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  6. Classic gravitational tests of post-Einsteinian theories.Nicolae Sfetcu - manuscript
    Albert Einstein proposed three tests of general relativity, later named the classic tests of general relativity, in 1916: the precession of the perihelion of Mercury's orbit, sun light deflection, and the gravitational redshift of the light. For gravitational testing, the indirect effects of gravity are always used, usually particles that are influenced by gravity. In the presence of gravity, the particles move along curved geodesic lines. The sources of gravity that cause the curvature of spacetime are material bodies, (...)
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  7. Mie's Theories of Matter and Gravitation.Chris Smeenk - 2007 - In Jürgen Renn (ed.), The Genesis of General Relativity. Springer. pp. 1543-1553.
    Unifying physics by describing a variety of interactions – or even all interactions – within a common framework has long been an alluring goal for physicists. One of the most ambitious attempts at unification was made in the 1910s by Gustav Mie. Mie aimed to derive electromagnetism, gravitation, and aspects of the emerging quantum theory from a single variational principle and a well-chosen Lagrangian. Mie’s main innovation was to consider nonlinear field equations to allow for stable particle-like solutions (now called (...)
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  8. The relativistic theory of gravitation beyond general relativity.Alfonso Guillen Gomez - manuscript
    It presents the basics of the “Relativistic theory of gravitation”, with the inclusion of original texts, from various papers, published between 1987 and 2009, by theirs authors: S. S Gershtein, A. A. Logunov, Yu. M. Loskutov and M. A. Mestvirishvili, additionally, together with the introductions, summaries and conclusions of the author of this paper. The “Relativistic theory of gravitation” is a gauge theory, compatible with the theories of quantum physics of the electromagnetic, weak and strong forces, which defines gravity (...)
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  9. The relativistic theory of gravitation beyond general relativity.Guillen Gomez Alfonso Leon - manuscript
    It presents the basics of the “Relativistic theory of gravitation”, with the inclusion of original texts, from various papers, published between 1987 and 2009, by theirs authors: S. S Gershtein, A. A. Logunov, Yu. M. Loskutov and M. A. Mestvirishvili, additionally, together with the introductions, summaries and conclusions of the author of this paper. The “Relativistic theory of gravitation” is a gauge theory, compatible with the theories of quantum physics of the electromagnetic, weak and strong forces, which defines gravity (...)
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  10. How Hilbert’s attempt to unify gravitation and electromagnetism failed completely, and a plausible resolution.Victor Christianto, Florentin Smarandache & Robert N. Boyd - manuscript
    In the present paper, these authors argue on actual reasons why Hilbert’s axiomatic program to unify gravitation theory and electromagnetism failed completely. An outline of plausible resolution of this problem is given here, based on: a) Gödel’s incompleteness theorem, b) Newton’s aether stream model. And in another paper we will present our calculation of receding Moon from Earth based on such a matter creation hypothesis. More experiments and observations are called to verify this new hypothesis, albeit it is inspired from (...)
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  11. Tests et anomalies des théories de la gravité post-newtoniennes.Nicolae Sfetcu - manuscript
    Dans la première édition du Principia, Newton considérait que des expériences avec le pendule lui permettraient de déchiffrer les différents types de force de résistance et leur variation avec la vitesse. Habituellement, le « laboratoire » des tests gravitationnels était les corps célestes, les systèmes astrophysiques. Mais ces tests sont perturbés par des effets non gravitationnels. Le « laboratoire » le plus utilisé était le système solaire. Récemment, les scientifiques se sont concentrés sur l'observation des pulsars binaires pour la vérification (...)
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  12. Electromagnetic and Gravitational Pictures of the World.Sergey G. Fedosin - 2007 - Apeiron 14 (4):385-413.
    The review of the theory of electromagnetic field together with the special and general theories of relativity has been made. The similar theory of gravitation has been presented which has the property of Lorentz-invariancy in its own representation in which the information is transferred at the speed of propagation of the gravitational field. Generalization of the specified gravitation theory on noninertial reference systems has been made with the help of the mathematical apparatus of the general relativity. It allows (...)
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  13. Gravitational decoherence: A thematic overview.C. Anastopoulos & B. L. Hu - 2022 - AVS Quantum Science 4:015602.
    Gravitational decoherence (GD) refers to the effects of gravity in actuating the classical appearance of a quantum system. Because the underlying processes involve issues in general relativity (GR), quantum field theory (QFT), and quantum information, GD has fundamental theoretical significance. There is a great variety of GD models, many of them involving physics that diverge from GR and/or QFT. This overview has two specific goals along with one central theme:(i) present theories of GD based on GR and QFT (...)
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  14. Épistémologie de la gravité quantique.Sfetcu Nicolae - manuscript
    La gravité quantique a nécessité la prise en compte des questions épistémologiques fondamentales, qui peuvent être identifiées en philosophie avec le problème corps-esprit et le problème du libre arbitre . Ces questions ont influencé l'épistémologie de la mécanique quantique sous la forme du « parallélisme psycho-physique » de von Neumann et l'analyse ultérieure de la thèse de Wigner selon laquelle « l'effondrement du paquet d'ondes » se produit dans l'esprit de « l'observateur ». La gravité quantique en cosmologie pose le (...)
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  15. Incommensurability Tenet and Modern Theory of Gravity.Rinat M. Nugayev - 1989 - In Lev Bazhenov Azaria Polikarov (ed.), Cosmos,Physics,Philosophy. pp. 37-39.
    An apparent incommensurability of two leading gravitational paradigms (metric and nonmetric) is considered. It is conjectured that the application of neutral language of A.P. Lightman, D.L. Lee and Kip S. Thorne (“The Foundation of Theory of Gravitational Theories”. Phys. Rev. D 1973, vol.7, pp.3563-3572) can help to solve the theory –choice problem in principle. Key words: neutral language, theory choice, gravity.
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  16. Gravité et tests gravitationnels.Nicolae Sfetcu - manuscript
    Les théories scientifiques en général, en physique en particulier, sont confirmées (temporairement) par des expériences vérifiant les affirmations et les prédictions des théories, jetant ainsi les bases de la connaissance scientifique. Francis Bacon a été le premier à soutenir le concept d'une expérience cruciale, qui peut décider la validité d'une hypothèse ou d'une théorie. Plus tard, Newton a soutenu que les théories scientifiques sont directement induites par les résultats expérimentaux et les observations, excluant les hypothèses non vérifiées. DOI: 10.13140/RG.2.2.34744.70403 .
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  17. Unification de la gravité avec les autres forces fondamentales.Sfetcu Nicolae - manuscript
    Plusieurs théories unificatrices ont été proposées. Une grande unification implique l'existence d'une force électronucléaire. La dernière étape de l'unification nécessiterait une théorie qui inclue à la fois la mécanique quantique et la gravité par la relativité générale (« la théorie finale »). Après 1990, certains physiciens considèrent que la théorie M à 11 dimensions, souvent identifiée à l'une des cinq théories des supercordes perturbateurs, ou parfois à la supergravité à supersymétrie maximale supersymétrique à 11 dimensions, est la théorie finale. L'idée (...)
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  18. L'heuristique de la gravité quantique.Sfetcu Nicolae - manuscript
    Il existe trois problèmes majeurs dans la conception d'une théorie de la gravité quantique: la théorie quantique et la relativité générale présentent en elles-mêmes des problèmes conceptuels importants, les bases fondamentales disparates des deux théories génèrent de nouveaux problèmes majeurs en essayant de les combiner, et le contraste entre l'absence d'une théorie de la gravité quantique satisfaisante et des théories des ingrédients réussis soulèvent des questions sur la nature et la fonction de la discussion philosophique de la gravité quantique. DOI: (...)
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  19. L'heuristique de la gravité newtonienne.Nicolae Sfetcu - manuscript
    L'exemple classique d'un programme de recherche réussi est la théorie gravitationnelle de Newton, probablement le programme de recherche lakatosien le plus réussi. Initialement, la théorie gravitationnelle de Newton était confrontée à de nombreuses « anomalies » (« contre-exemples ») et contredisait les théories observationnelles qui soutenaient ces anomalies. Mais les partisans du programme de recherche sur la gravité newtonienne ont transformé chaque anomalie en cas corroborants. De plus, ils ont eux-mêmes indiqué des contre-exemples qu'ils ont ensuite expliqués à travers la (...)
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  20. Epistémologie de la gravité expérimentale - Rationalité scientifique.Nicolae Sfetcu - 2020 - Drobeta Turnu Severin: MultiMedia Publishing.
    L'évolution des tests gravitationnels dans une perspective épistémologique encadré dans le concept de reconstruction rationnelle d'Imre Lakatos, fondée sur sa méthodologie de programmes de recherche. Contrairement à d'autres travaux sur le même sujet, la période évaluée est très longue, allant de la philosophie naturelle de Newton aux théories de la gravité quantique d'aujourd'hui. Afin d'expliquer de manière plus rationnelle l'évolution complexe du concept de gravité du siècle dernier, je propose une extension naturelle de la méthodologie des programmes de recherche que (...)
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  21. Newton's Law of Universal Gravitation and Hume's Conception of Causality.Matias Slavov - 2013 - Philosophia Naturalis 50 (2):277-305.
    This article investigates the relationship between Hume’s causal philosophy and Newton ’s philosophy of nature. I claim that Newton ’s experimentalist methodology in gravity research is an important background for understanding Hume’s conception of causality: Hume sees the relation of cause and effect as not being founded on a priori reasoning, similar to the way that Newton criticized non - empirical hypotheses about the properties of gravity. However, according to Hume’s criteria of causal inference, the law of universal gravitation is (...)
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  22. Einstein and gravitational waves.Alfonso Leon Guillen Gomez - manuscript
    The author presents the history of gravitational waves according to Einstein, linking it to his biography and his time in order to understand it in his connection with the history of the Semites, the personality of Einstein in the handling of his conflict-generating circumstances in his relationships competition with his colleagues and in the formulation of the so-called general theory of relativity. We will fall back on the vicissitudes that Einstein experienced in the transition from his scientific work to (...)
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  23. Burgess and the Bucket: The Emergence of Spacetime in Classical Theories of Gravitation.Joshua Babic & Lorenzo Cocco - forthcoming - Synthese.
    The paper studies in detail a precise formal construction of spacetime from matter suggested by the logician John Burgess. We presuppose a continuous and perdurantistic matter ontology. The result is a systematic method to translate claims about the geometry of a flat relativistic, or classical, spacetime into claims about geometrical relations between matter points. The approach is extended to electric and magnetic fields by treating them as multifields defined on matter, rather than as fields in the vacuum. A few tentative (...)
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  24. (1 other version)Isaac Newton vs. Robert Hooke on the law of universal gravitation.Nicolae Sfetcu - manuscript
    One of the most disputed controversy over the priority of scientific discoveries is that of the law of universal gravitation, between Isaac Newton and Robert Hooke. Hooke accused Newton of plagiarism, of taking over his ideas expressed in previous works. In this paper I try to show, on the basis of previous analysis, that both scientists were wrong: Robert Hooke because his theory was basically only ideas that would never have materialized without Isaac Newton's mathematical support; and the latter was (...)
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  25. Gravity and gravitational tests.Nicolae Sfetcu - manuscript
    Theories in science in general, and in physics in particular, are confirmed (temporarily) by experiments that verify the assertions and predictions of theories, thus laying the groundwork for scientific knowledge. Francis Bacon was the first to support the concept of a crucial experiment, which can decide the validity of a hypothesis or theory. Later, Newton argued that scientific theories are directly induced by experimental results and observations, excluding untested hypotheses. DOI: 10.13140/RG.2.2.33549.08167.
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  26. Tests de la gravité quantique.Sfetcu Nicolae - manuscript
    Le test primordial de toute théorie quantique de la gravité est la reproduction des succès de la relativité générale. Cela implique de reconstruire la géométrie locale à partir des observables non locaux. De plus, la gravité quantique devrait probablement prédire la topologie à grande échelle de l'Univers, qui pourrait bientôt être mesurable , et les phénomènes à l'échelle de Planck. Il existe déjà une prédiction liée à la gravité quantique: l'existence et le spectre du rayonnement Hawking du trou noir, une (...)
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  27.  40
    Theory of Universality.Surya Narayana Kasibhatla - 2019 - Iosr - Jap 11 (2):19-115. Translated by Surya Narayana Kasibhatla.
    This theory is an attempt to describe the universal phenomena like space, time, matter and energy as an inter-relationship bound by a newly discovered force named as the universal force. The universal force is shown to be the force of gravitation, electricity, magnetism, strong nuclear and weak nuclear forces. I believe any other force, hitherto fore not discovered; also, can be explained in terms of this universal force. Liberal use of wave-particle duality, relativity, quantum concepts is made to achieve a (...)
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  28. Theory, Evidence, Data: Themes from George E. Smith.Marius Stan & Christopher Smeenk - 2023 - Springer.
    A volume of papers inspired by the work of George E. Smith on confirmation and evidence in advanced science—from Newton's gravitation theory to the physics of molecules.
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  29. Einstein's gravitation is Einstein-Grossmann's equations.Alfonso Leon Guillen Gomez - 2015 - Journal of Advances in Physics 11 (3):3099-3110.
    While the philosophers of science discuss the General Relativity, the mathematical physicists do not question it. Therefore, there is a conflict. From the theoretical point view “the question of precisely what Einstein discovered remains unanswered, for we have no consensus over the exact nature of the theory 's foundations. Is this the theory that extends the relativity of motion from inertial motion to accelerated motion, as Einstein contended? Or is it just a theory that treats gravitation geometrically in the spacetime (...)
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  30. Dirac-Type Equations in a Gravitational Field, with Vector Wave Function.Mayeul Arminjon - 2008 - Foundations of Physics 38 (11):1020-1045.
    An analysis of the classical-quantum correspondence shows that it needs to identify a preferred class of coordinate systems, which defines a torsionless connection. One such class is that of the locally-geodesic systems, corresponding to the Levi-Civita connection. Another class, thus another connection, emerges if a preferred reference frame is available. From the classical Hamiltonian that rules geodesic motion, the correspondence yields two distinct Klein-Gordon equations and two distinct Dirac-type equations in a general metric, depending on the connection used. Each of (...)
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  31. L'espace et le temps existent-ils ? Le mystère de la gravité quantique.Baptiste Le Bihan - 2018 - Implications Philosophiques 1.
    La physique contemporaine pourrait bien nous livrer un enseignement incroyable, à savoir que l'espace et le temps n'existent pas fondamentalement. Je présenterai succinctement les ontologies suggérées par les deux principaux programmes de recherche en gravité quantique : la théorie des cordes et la gravité quantique à boucles. Je soutiendrai ensuite qu'il est fructueux de prendre les différentes conceptions ontologiques de la conscience en philosophie de l'esprit en modèles pour la construction de solutions au problème de l'émergence de l'espace-temps.
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  32. Mathematical Nature of Reality, Plus Gravitation-Electromagnetism Unification, Derived from Revised Gravitational Tidal Forces and Mass-from-Gravity Concept.Rodney Bartlett - manuscript
    This article had its beginning with Einstein's 1919 paper "Do gravitational fields play an essential role in the structure of elementary particles?" Together with General Relativity's statement that gravity is not a pull but is a push caused by the curvature of space-time, a hypothesis for Earth's ocean tides was developed that does not solely depend on the Sun and Moon as Kepler and Newton believed. It also borrows from Galileo. The breakup of planets and asteroids by white dwarfs, (...)
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  33. Selective Realism and the Framework/Interaction Distinction: A Taxonomy of Fundamental Physical Theories.Federico Benitez - 2019 - Foundations of Physics 49 (7):700-716.
    Following the proposal of a new kind of selective structural realism that uses as a basis the distinction between framework and interaction theories, this work discusses relevant applications in fundamental physics. An ontology for the different entities and properties of well-known theories is thus consistently built. The case of classical field theories—including general relativity as a classical theory of gravitation—is examined in detail, as well as the implications of the classification scheme for issues of realism in quantum (...)
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  34.  58
    Alternative concept on space used in the BSM – Supergravitational Unified Theory unveils the connection between the micro-cosmos and Universe.Stoyan Sarg Sargoytchev - unknown
    The theory is based on an original alternative space-time concept that leads to a new vision of the micro-cosmos and Universe. The relationship between the forces in Nature is unveiled by adopting the following framework: (1) Empty space without any physical properties and restrictions; (2) Two fundamental particles of superdense protomatter with parameters associated with Planck’s scale; (3) A Fundamental law of Supergravitation (SG) with forces inversely proportional to the cube of distance in a pure empty space. An enormous abundance (...)
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  35. Heuristique de la théorie des cordes.Sfetcu Nicolae - manuscript
    Comme la théorie des cordes n'a jusqu'à présent pas pu expliquer les phénomènes, il peut sembler que cela confirme l'opinion de Feyerabend selon laquelle il n'y a pas de « méthode » de la science. Et pourtant, la théorie des cordes est toujours le programme de recherche le plus actif pour la gravité quantique. Mais, par rapport à d'autres théories non falsifiables, cela a quelque chose de plus, en particulier : le langage mathématique, avec une logique claire de décoctions. Jusqu'à (...)
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  36. La revendication de Hooke sur la loi de la gravité.Nicolae Sfetcu - manuscript
    Dans une note intitulée « Un état vrai de l'affaire et la controverse entre Sr Isaak Newton et le Dr Robert Hooke comme priorité de cette noble hypothèse du mouvement des planètes autour du Soleil en tant que leurs centres » non publié au cours de sa vie, Hooke a décrit sa théorie de la gravité. Pour soutenir sa « priorité », Hooke cite ses conférences sur les mouvements planétaires du 23 mai 1666, « Une tentative de prouver le mouvement (...)
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  37. ΛCDM and MOND: A debate about models or theory?Melissa Jacquart - 2021 - Studies in History and Philosophy of Science Part A 89 (C):226-234.
    The debate between ΛCDM and MOND is often cast in terms of competing gravitational theories. However, recent philosophical discussion suggests that the ΛCDM–MOND debate demonstrates the challenges of multiscale modeling in the context of cosmological scales. I extend this discussion and explore what happens when the debate is thought to be about modeling rather than about theory, offering a model-focused interpretation of the ΛCDM–MOND debate. This analysis shows how a model-focused interpretation of the debate provides a better understanding (...)
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  38. Prolifération des théories post-newtoniennes.Nicolae Sfetcu - manuscript
    Les théoriciens ont formulé un ensemble de critères fondamentaux que toute théorie de la gravité devrait satisfaire, deux purement théoriques et deux fondés sur des preuves expérimentales. Ainsi, une théorie doit être : complet (capable d'analyser à partir des « premiers principes » le résultat de toute expérience d'intérêt), auto-cohérent (sa prédiction pour le résultat de chaque expérience doit être unique), relativiste (à la limite où la gravité est négligée par rapport à d'autres interactions physiques, les lois non gravitationnelles de (...)
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  39. Towards a Theory of Everything Part I - Introduction of Consciousness in Electromagnetic Theory, Special and General Theory of Relativity.RamLakhan Pandey Vimal - 2010 - Neuroquantology 8 (2):206-230.
    Theory of everything must include consciousness. In this Part I of the series of three articles, we introduce the subjective experience (SE) and/or proto‐experience (PE) aspect of consciousness in classical physics, where PEs are precursors of SEs. In our dualaspect‐ dual‐mode PE‐SE framework, it was hypothesized that fundamental entities (strings or elementary particles: fermions and bosons) have two aspects: (i) material aspect such as mass, charge, spin, and space‐time, and (ii) mental aspect, such as experiences. There are three competing hypotheses: (...)
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  40. Prolifération des théories post-einsteiniennes - Formalisme paramétrisé post-newtonien (PPN).Nicolae Sfetcu - manuscript
    Immédiatement après l'élaboration et le succès de la relativité générale, des théories alternatives pour la gravité ont commencé à apparaître. En développant ces théories, de nombreuses stratégies différentes (heuristiques positives) ont été essayées, en ajoutant de nouvelles hypothèses à la RG, en utilisant un espace-temps pour lequel l'univers est statique, des hypothèses qui éliminent les singularités gravitationnelles, etc. Pour l'évaluation des modèles de gravité, plusieurs séries de tests ont été proposées. Le formalisme paramétrisé post-newtonien (PPN) détaille les paramètres qui différencient (...)
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  41. Colombeau solutions to Einstein field equations.Gravitational singularities.Jaykov Foukzon - manuscript
    In contemporary mathematics, a Colombeau algebra of Colombeau generalized functions is an algebra of a certain kind containing the space of Schwartz distributions. While in classical distribution theory a general multiplication of distributions is not possible, Colombeau algebras provide a rigorous framework for this. Remark 1.1.1.Such a multiplication of distributions has been a long time mistakenly believed to be impossible because of Schwartz’ impossibility result, which basically states that there cannot be a differential algebra containing the space of distributions and (...)
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  42. Classical theory of singularities.Nicolae Sfetcu - manuscript
    The singularities from the general relativity resulting by solving Einstein's equations were and still are the subject of many scientific debates: Are there singularities in spacetime, or not? Big Bang was an initial singularity? If singularities exist, what is their ontology? Is the general theory of relativity a theory that has shown its limits in this case?
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  43. Origin and Resolution of Theory-Choice Situations in Modern Theory of gravity.Rinat M. Nugayev - 1987 - Methodology and Science 20 (4):177-197.
    A methodological model of origin and settlement of theory-choice situations (previously tried on the theories of Einstein and Lorentz in electrodynamics) is applied to modern Theory of Gravity. The process of origin and growth of empirically-equivalent relativistic theories of gravitation is theoretically reproduced. It is argued that all of them are proposed within the two rival research programmes – (1) metric (A. Einstein et al.) and (2) nonmetric (H. Poincare et al.). Each programme aims at elimination of the (...)
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  44. A methodological note on proving agreement between the Elementary Process Theory and modern interaction theories.Cabbolet Marcoen - 2022 - In Marcoen J. T. F. Cabbolet (ed.), And now for something completely different: the Elementary Process Theory. Revised, updated and extended 2nd edition of the dissertation with almost the same title. Utrecht: Eburon Academic Publishers. pp. 373-382.
    The Elementary Process Theory (EPT) is a collection of seven elementary process-physical principles that describe the individual processes by which interactions have to take place for repulsive gravity to exist. One of the two main problems of the EPT is that there is no proof that the four fundamental interactions (gravitational, electromagnetic, strong, and weak) as we know them can take place in the elementary processes described by the EPT. This paper sets forth the method by which it can (...)
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  45. Gravity as Archimedes? Thrust and a Bifurcation in that Theory.Mayeul Arminjon - 2004 - Foundations of Physics 34 (11):1703-1724.
    Euler’s interpretation of Newton’s gravity (NG) as Archimedes’ thrust in a fluid ether is presented in some detail. Then a semi-heuristic mechanism for gravity, close to Euler’s, is recalled and compared with the latter. None of these two ‘‘gravitational ethers’’ can obey classical mechanics. This is logical since the ether defines the very reference frame, in which mechanics is defined. This concept is used to build a scalar theory of gravity: NG corresponds to an incompressible ether, a compressible ether (...)
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  46. The Universe:a Philosophical derivation of a Final Theory.John F. Thompson - manuscript
    The reason for physics’ failure to find a final theory of the universe is examined. Problems identified are: the lack of unequivocal definitions for its fundamental elements (time, length, mass, electric charge, energy, work, matter-waves); the danger of relying too much on mathematics for solutions; especially as philosophical arguments conclude the universe cannot have a mathematical basis. It does not even need the concept of number to exist. Numbers and mathematics are human inventions arising from the human predilection for measurement. (...)
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  47. Testing the relativistic theories of gravity.Nicolae Sfetcu - manuscript
    In developing general relativity, Einstein was led by theoretical criteria of elegance and simplicity. His theory initially encountered "three classic tests": perihelion precession of Mercury's orbit, deflection of light by the Sun, and gravitational redshift of light. There are large differences in predictions between general relativity and classical physics, such as gravitational time dilation, gravitational lensing, gravitational redshift of light, and so on. And there are many relativistic theories of gravity, bifurcated or independent, but Einstein's (...)
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  48. A Semi-Classical Model of the Elementary Process Theory Corresponding to Non-Relativistic Classical Mechanics.Marcoen J. T. F. Cabbolet - 2022 - In And now for something completely different: the Elementary Process Theory. Revised, updated and extended 2nd edition of the dissertation with almost the same title. Utrecht: Eburon Academic Publishers. pp. 255-287.
    Currently there are at least four sizeable projects going on to establish the gravitational acceleration of massive antiparticles on earth. While general relativity and modern quantum theories strictly forbid any repulsive gravity, it has not yet been established experimentally that gravity is attraction only. With that in mind, the Elementary Process Theory (EPT) is a rather abstract theory that has been developed from the hypothesis that massive antiparticles are repulsed by the gravitational field of a body of (...)
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  49. Proliferation of Post-Newtonian, Non-Relativistic Theories.Nicolae Sfetcu - manuscript
    Theoreticians have formulated a set of fundamental criteria that any theory of gravity should satisfy, two purely theoretical and two that are based on experimental evidence. Thus, a theory must be complete (capable of analyzing from the "first principles" the result of any experiment of interest), self-consistent (its prediction for the outcome of each experiment must be unique), relativistic (at the limit when gravity is neglected compared to other physical interactions, non-gravitational laws of physics must be reduced to special (...)
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  50. A Decoherence-Based Approach to the Classical Limit in Bohm’s Theory.Davide Romano - 2023 - Foundations of Physics 53 (2):1-27.
    The paper explains why the de Broglie–Bohm theory reduces to Newtonian mechanics in the macroscopic classical limit. The quantum-to-classical transition is based on three steps: (i) interaction with the environment produces effectively factorized states, leading to the formation of _effective wave functions_ and hence _decoherence_; (ii) the effective wave functions selected by the environment—the pointer states of decoherence theory—will be well-localized wave packets, typically Gaussian states; (iii) the quantum potential of a Gaussian state becomes negligible under standard classicality conditions; therefore, (...)
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