Journal articles: 'Massive gravitation'

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Baiderin, A. A., I. P. Denisova, and V. S. Rostovsky. "Exact plane-wave solution of equations of gravitation theory with massive graviton." Izvestiya vysshikh uchebnykh zavedenii. Fizika 64, no. 1 (2021): 10–15. http://dx.doi.org/10.17223/00213411/64/1/10.

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The theory of gravitation with a massive graviton, which was proposed by Visser, is considered. The exact solution of this theory is found when the source of the gravitational field is plane scalar wave. The Hamilton-Jacobi method obtained the laws of motion of massive and massless particles in this gravitational field.

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Argyris, John, and Corneliu Ciubotariu. "Massive Gravitons in General Relativity." Australian Journal of Physics 50, no. 5 (1997): 879. http://dx.doi.org/10.1071/p97002.

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In the framework of a generalisation of linear gravitation to the case when the gravitons have nonzero rest mass, we obtain a result analogous to that obtained by Regge and Wheeler, that is, the energy of the gravitational waves is trapped in the ‘material’ (interior) metric of the curved space–time. We show that the concept of a nonzero rest mass graviton may be defined in two ways: (i) phenomenologically, by introducing of a mass term in the linear Lagrangian density, as in Proca electrodynamics, and (ii) self-consistently, by solving Einstein’s equations in the conformally flat case. We find that the rest mass of the graviton may be given in terms of the three fundamental constants (gravitational, Planck, and light velocity constants) and it is a function of the density of cosmic matter.

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Ahmed, Shohel, and Md Showkat Ali. "Numerical Relativity: Solving Geodesics equation for Massive Particle Around Black Holes Horizon." GANIT: Journal of Bangladesh Mathematical Society 35 (June 28, 2016): 79–85. http://dx.doi.org/10.3329/ganit.v35i0.28571.

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General relativity is the most beautiful physical theory ever invented. It describes one of the most pervasive features of the world we experience - gravitation. The gravitational field acts on nearby matter defines by the curvature of space-time. The black holes of nature are the most perfect macroscopic objects there are in the universe that constructed our concept of space-time. In this paper we use Einsteins general relativity to model the motions of massive particles around the two black holes: static and rotating. These equations of motion around black holes will be studied with special focus towards the variation of symmetry by the change of gravitational effect.GANIT J. Bangladesh Math. Soc.Vol. 35 (2015) 79-85

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Eingorn, Maxim. "Cosmological law of universal gravitation." International Journal of Modern Physics D 26, no. 10 (August 20, 2017): 1750121. http://dx.doi.org/10.1142/s0218271817501218.

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Without exceeding the limits of the conventional ΛCDM paradigm, we argue for Yukawa law of interparticle interaction as the law of gravitation in the real expanding inhomogeneous universe. It covers the whole space and comes up to take place of Newtonian gravity, which is restricted exclusively to sub-horizon distances. The large-scale screening of gravitational interaction between every two nonrelativistic massive particles is ensured by the homogeneous cosmological background (specifically, by the nonzero average rest mass density of nonrelativistic matter). We take advantage of the uniform matter distribution case (i.e. the homogeneous universe limit) to demonstrate superiority of Yukawa gravity. Attention is also devoted to the concrete particular case of inhomogeneity.

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Yadav, Ranjit Prasad. "Theory of General Relativity: Historical Perspective." Academic Voices: A Multidisciplinary Journal 4 (March 28, 2015): 49–52. http://dx.doi.org/10.3126/av.v4i0.12358.

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General relativity was developed by Albert Einstein near about 100 Years ago. This article attempt to give an outline about the brief history of general theory of relativity and to understand the background to the theory we have to look at how theories of gravitation developed. Before the advent of GR, Newton's law of gravitation had been accepted for more than two hundred years as a valid description of the gravitational force between masses i.e. gravity was the result of an attractive force between massive objects. General relativity has developed in to an essential tool in modern astrophysics. It provides the foundation for the understanding of black holes, regions of space where gravitational attraction is strong that not even light can escape and also a part of the big bang model of cosmology.DOI: http://dx.doi.org/10.3126/av.v4i0.12358Academic Voices Vol.4 2014: 49-52

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Bhattacharjee, Dr Iresh Ranjan. "Biological Phenomena Mimic Astrophysical Principles Of Gravitation – Opening Perspective." Volume 1 Issue 6 1, no. 6 (August 31, 2018): 1–16. http://dx.doi.org/10.31426/ijamsr.2018.1.6.611.

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It is conjectured that phenomena in biological microworld could be equated with astrophysical principles of gravitation. Fluids, gases that constitute 50-90 % of the total accredited biomass causes seclusion from stronger external gravitational fields. Seclusion due to buoyant condition is reflected in apparent ‘weight’ reduced. The g-value (self) to the tune of nanometer per second square in a massive body of a planet may be negligible, but in an isolated living mass at picometer distance, such acceleration is quite a significant force. Homogeneous and heterogeneous accretion; heating and cooling phenomena as well as the rhythmic pattern of growth due to elastic collisions in massive star; heat transfer mechanisms viz. radiation, (perspiration), conduction and convection; site of human core body temperature at liver, kidney, heart and parts of brain at central region under initial circular fetus situation; or coldest part of the periphery at toe, foot, hand demonstrates similarity between biological and astrophysical words

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ACCIOLY, ANTONIO, RUBEN ALDROVANDI, and RICARDO PASZKO. "IS THE EQUIVALENCE PRINCIPLE DOOMED FOREVER TO DANTE'S INFERNO ON ACCOUNT OF QUANTUM MECHANICS?" International Journal of Modern Physics D 15, no. 12 (December 2006): 2249–55. http://dx.doi.org/10.1142/s0218271806009686.

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It is commonly assumed that the equivalence principle can coexist without conflict with quantum mechanics. We shall argue here that, contrary to popular belief, this principle does not hold in quantum mechanics. We illustrate this point by computing the second-order correction for the scattering of a massive scalar boson by a weak gravitational field, treated as an external field. The resulting cross-section turns out to be mass-dependent. A way out of this dilemma would be, perhaps, to consider gravitation without the equivalence principle. At first sight, this seems to be a too much drastic attitude toward general relativity. Fortunately, the teleparallel version of general relativity — a description of the gravitational interaction by a force similar to the Lorentz force of electromagnetism and that, of course, dispenses with the equivalence principle — is equivalent to general relativity, thus providing a consistent theory for gravitation in the absence of the aforementioned principle.

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Garcia de Andrade, L. C. "Torsion, massive electrodynamics and gravitation induced by scalar fields." Astrophysics and Space Science 198, no. 1 (1992): 79–83. http://dx.doi.org/10.1007/bf00644301.

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Geracie, Michael, Kartik Prabhu, and Matthew M. Roberts. "Curved non-relativistic spacetimes, Newtonian gravitation and massive matter." Journal of Mathematical Physics 56, no. 10 (October 2015): 103505. http://dx.doi.org/10.1063/1.4932967.

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Bessada, Dennis, and Oswaldo D. Miranda. "CMB polarization in theories of gravitation with massive gravitons." Classical and Quantum Gravity 26, no. 4 (January 29, 2009): 045005. http://dx.doi.org/10.1088/0264-9381/26/4/045005.

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Moffat, J. W., and E. Woolgar. "Motion of massive bodies: Testing the nonsymmetric gravitation theory." Physical Review D 37, no. 4 (February 15, 1988): 918–30. http://dx.doi.org/10.1103/physrevd.37.918.

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Snytnikov, Valeriy N., Olga P. Stoyanovskaya, and Olga A. Stadnichenko. "Can we expect the massive discs around young stellar objects class O-I to be a birthplace of planetesimal?" Proceedings of the International Astronomical Union 9, S310 (July 2014): 225–26. http://dx.doi.org/10.1017/s1743921314008357.

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AbstractPossibility of large bodies formation in massive discs of young stellar objects (YSO) class O-I was investigated. On the stage of YSO O-I the whole of factors: chemical composition of gas and solids, chemical catalytic reactions, the disc self-gravitation, the increased ratio of solids to gas surface density, adiabatic gas cooling provides favorable conditions for gravitational instabilities development. We simulated 3D dynamics of gas and dust under self-consistent gravitational field and reproduced the formation and evolution of the disc around the protostar. We found that for stars of Solar mass there are regimes when the disc of variable mass is unstable for the development of fast gravitational instabilities.

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Danielski, Camilla, and Nicola Tamanini. "Will gravitational waves discover the first extra-galactic planetary system?" International Journal of Modern Physics D 29, no. 14 (September 7, 2020): 2043007. http://dx.doi.org/10.1142/s0218271820430075.

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Gravitational waves have opened a new observational window through which some of the most exotic objects in the universe, as well as some of the secrets of gravitation itself, can now be revealed. Among all these new discoveries, we recently demonstrated15 that space-based gravitational wave observations will have the potential to detect a new population of massive circumbinary exoplanets everywhere inside our Galaxy. In this paper, we argue that these circumbinary planetary systems can also be detected outside the Milky Way, in particular within its satellite galaxies. Space-based gravitational wave observations might thus constitute the mean to detect the first extra-galactic planetary system, a target beyond the reach of standard electromagnetic searches.

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Yarman, Tolga, Metin Arik, Alexander Kholmetskii, and Ozan Yarman. "Super-massive objects in Yarman–Arik–Kholmetskii (YARK) gravitation theory." Canadian Journal of Physics 94, no. 3 (March 2016): 271–78. http://dx.doi.org/10.1139/cjp-2015-0689.

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We continue to analyze the implications of the gravitational framework of our theoretical approach, christened YARK (abbreviated from Yarman–Arik–Kholmetskii), with respect to super-massive celestial bodies. We emphasize in particular that a gravitating test particle in the presence of a ponderable mass must adhere to the law of energy conservation, which remarkably does not yield any singularity according to YARK. Even so, for a given spherically shaped extremely compact super-massive body, one can achieve a theoretical radius below which “light” of, say, the visible frequency range can indeed be trapped. Yet, such a radius comes out to be tens of times shorter than the threshold radius for black hole formation as established by the general theory of relativity (GTR). In accordance with our derivations, the minimal mass for a celestial object capable of recapturing emitted light in its environs — similar to textbook “intermediate class black holes” — is found to be about 103MS, where MS stands for the mass of the Sun. For less massive celestial objects, the crucial radius that produces a “YARK black hole” (i.e., without singularity) corresponds to a higher density than the density of a baryon; and hence, such entities cannot apparently exist in nature. Black holes allowed therefore in our approach are not related, in any case, to the singularity conceptualization of GTR. As a consequence, we are able to present a resolution to the “black hole information paradox”. The findings of YARK will be discussed hereinafter with regards to the foundations of observational cosmology.

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Yadav, Anil Kumar. "Anisotropic massive strings in the scalar-tensor theory of gravitation." Research in Astronomy and Astrophysics 13, no. 7 (June 25, 2013): 772–82. http://dx.doi.org/10.1088/1674-4527/13/7/002.

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Tripathy, S. K., S. K. Nayak, S. K. Sahu, and T. R. Routray. "Massive String Cloud Cosmologies in Saez-Ballester Theory of Gravitation." International Journal of Theoretical Physics 48, no. 1 (July 24, 2008): 213–25. http://dx.doi.org/10.1007/s10773-008-9796-9.

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Wollmanm, E. R. "A grain plasma model of galaxies." Laser and Particle Beams 6, no. 3 (August 1988): 545–53. http://dx.doi.org/10.1017/s0263034600005462.

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Electrical quasi-neutrality is not a general property of a thermalized self-gravitating plasma. If the massive component of a two-component plasma consists of charged macroscopic solid grains for which the charge-to-mass ratio is of order then self-gravitation and thermalization lead to substantial large-scale charge separation. An alternative statement of the condition for substantial equilibrium charge separation is that the Jeans length and Debye length of the plasma are similar.We consider a system of condensations in such a plasma and show that properties of the system are similar to observed properties of the system of galaxies.

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Struckmeier, J., J. Muench, P. Liebrich, M. Hanauske, J. Kirsch, D. Vasak, L. Satarov, and H. Stoecker. "Canonical transformation path to gauge theories of gravity-II: Space-time coupling of spin-0 and spin-1 particle fields." International Journal of Modern Physics E 28, no. 01n02 (February 2019): 1950007. http://dx.doi.org/10.1142/s0218301319500071.

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The generic form of space-time dynamics as a classical gauge field theory has recently been derived, based on only the action principle and on the principle of general relativity. It was thus shown that Einstein’s general relativity is the special case where (i) the Hilbert Lagrangian (essentially the Ricci scalar) is supposed to describe the dynamics of the “free” (uncoupled) gravitational field, and (ii) the energy–momentum tensor is that of scalar fields representing real or complex structureless (spin-[Formula: see text]) particles. It followed that all other source fields — such as vector fields representing massive and nonmassive spin-[Formula: see text] particles — need careful scrutiny of the appropriate source tensor. This is the subject of our actual paper: we discuss in detail the coupling of the gravitational field with (i) a massive complex scalar field, (ii) a massive real vector field, and (iii) a massless vector field. We show that different couplings emerge for massive and nonmassive vector fields. The massive vector field has the canonical energy–momentum tensor as the appropriate source term — which embraces also the energy density furnished by the internal spin. In this case, the vector fields are shown to generate a torsion of space-time. In contrast, the system of a massless and charged vector field is associated with the metric (Hilbert) energy–momentum tensor due to its additional [Formula: see text] symmetry. Moreover, such vector fields do not generate a torsion of space-time. The respective sources of gravitation apply for all models of the dynamics of the “free” (uncoupled) gravitational field — which do not follow from the gauge formalism but must be specified based on separate physical reasoning.

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Louzada, H. L. C. "The Einstein–Hilbert gravitation with minimum length." International Journal of Modern Physics A 33, no. 13 (May 9, 2018): 1850079. http://dx.doi.org/10.1142/s0217751x18500793.

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We study the Einstein–Hilbert gravitation with the deformed Heisenberg algebra leading to the minimum length, with the intention to find and estimate the corrections in this theory, clarifying whether or not it is possible to obtain, by means of the minimum length, a theory, in D[Formula: see text]=[Formula: see text]4, which is causal, unitary and provides a massive graviton. Therefore, we will calculate and analyze the dispersion relationships of the considered theory.

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KÜHNE, RAINER W. "GAUGE THEORY OF GRAVITY REQUIRES MASSIVE TORSION FIELD." International Journal of Modern Physics A 14, no. 16 (June 30, 1999): 2531–35. http://dx.doi.org/10.1142/s0217751x99001251.

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One of the greatest unsolved issues of the physics of this century is to find a quantum field theory of gravity. According to a vast amount of literature, unification of quantum field theory and gravitation requires a gauge theory of gravity which includes torsion and an associated spin field. Various models including either massive or massless torsion fields have been suggested. We present arguments for a massive torsion field, where the probable rest mass of the corresponding spin three gauge boson is the Planck mass.

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Sharif, M. "Comments on torsion, massive electrodynamics and gravitation induced by scalar fields." Astrophysics and Space Science 238, no. 2 (April 1996): 309–10. http://dx.doi.org/10.1007/bf00641695.

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Chugreev, Yu V. "Cosmological consequences of the relativistic theory of gravitation with massive gravitons." Theoretical and Mathematical Physics 79, no. 2 (May 1989): 554–58. http://dx.doi.org/10.1007/bf01016538.

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Kirzhnits, D. A., and A. A. Shatskii. "On the electrization caused by the gravitation of a massive body." Astrophysics 39, no. 3 (July 1996): 272–77. http://dx.doi.org/10.1007/bf02072000.

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Portnov, Yuriy A. "Change in event horizon surface area as the source of nonmetricity field." International Journal of Geometric Methods in Modern Physics 15, no. 06 (May 8, 2018): 1850104. http://dx.doi.org/10.1142/s0219887818501049.

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This paper concerns the relationship between the nonmetricity 1-form and the change in entropy. Motion equations have been obtained for test bodies in a gravitational field created by a massive body with entropy varying over time. It has been shown that increasing entropy of the gravitational source will bring about an increase in the acceleration of the test body. Applied to the theory of gravitation with nonmetricity, black hole dynamics equations based on foundations laid by S. Hawking and J. Beckenstein, enabled identification of changes in black holes event horizon surface area as a putative source of nonmetricity field. The implication is that changes in event horizon area will affect test body motion. The latter property makes it possible to contemplate a completely new method for discovering short-lived microscopic black holes.

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Pignard, Olivier. "Dynamic medium of reference: A new theory of gravitation." Physics Essays 32, no. 4 (December 1, 2019): 422–38. http://dx.doi.org/10.4006/0836-1398-32.4.422.

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The object of this article is to present a new theory based on the introduction of a non-material medium which makes it possible to obtain a Preferred Frame of Reference (in the context of special relativity) or a Reference (in the context of general relativity), that is to say a dynamic medium of reference. The theory of the dynamic medium of reference is an extension of Lorentz‐Poincaré’s theory in the domain of gravitation in which instruments (clocks, rulers) are perturbed by gravitation and where only the measure of the speed of light always gives the same result. The presence of a massive body creates a centripetal flux of the medium, which has three fundamental effects: the dilatation of the period of material clocks, the contraction of the length of material rulers, and the slowdown of light. Thanks to the centripetal flux of the medium and these three effects, it is possible to find the correct expression of the deflection of a ray of light and the Shapiro delay. The dynamic medium of reference allows to establish a gravitational transformation and to find the fundamental equations of movement for light and matter. Hence, the theory of the dynamic medium of reference allows to find the main results of general relativity, but with important differences: The simultaneity is absolute, existence of the Preferred Frame of Reference, the physical reality is the universal present moment and not a global space-time (block-universe), light is slowed down by a gravitational field.

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Eingorn, Maxim, Andrew McLaughlin II, Ezgi Canay, Maksym Brilenkov, and Alexander Zhuk. "Gravitation in the Space with Chimney Topology." Physical Sciences Forum 2, no. 1 (February 22, 2021): 32. http://dx.doi.org/10.3390/ecu2021-09295.

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Searching for possible indicators of spatial topology of the Universe in the Cosmic Microwave Background data, one recognizes a quite promising interpretation which suggests that the shape of the space manifests itself in the form of anomalies in the large angular scale observations, such as the quadrupole and octopole alignment. Motivated by the presumptive existence of such a tempting connection, we study the chimney topology, T×T×R, which belongs to the class of toroidal topologies with a preferred direction. The infinite axis in this case may be attributed to the preferred axis of the aforementioned quadrupole and octopole alignment. We investigate the gravitational aspects of such a configuration. Namely, we reveal the form of the gravitational potential sourced by point-like massive bodies. Starting from the perturbed Einstein equations, which ensure the proper demonstration of relativistic effects, one can derive the Helmholtz equation for the scalar perturbation (gravitational potential). Through distinct alternative methods, we present the physically meaningful nontrivial exact solutions of this equation. Our approach excludes any presumptions regarding the spatial distribution of gravitating sources. We show that the particular solution that appears in the form of summed Yukawa potentials is indeed very convenient for the use in numerical calculations, in the sense that it provides the desired accuracy with fewer terms in the series.

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Bettwieser, E., K. J. Fricke, and R. Spurzem. "Why are Stellar Systems Anisotropic?" Symposium - International Astronomical Union 113 (1985): 301–3. http://dx.doi.org/10.1017/s0074180900147473.

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Spherical stellar systems show during their secular evolution the development of velocity anisotropy in their halo (cf. e.g. Hénon, 1971). The present study examines the general reasons for generation of anisotropy in stellar systems by means of a gaseous star cluster model including anisotropy. Moment equations of the Boltzmann equation are considered for spherical symmetry in coordinate space but not in velocity space closed in third order by a heat flux equation. The coefficient of heat conductivity is tailored to describe the flux of energy due to the cumulative effect of distant gravitative encounters and generalized to include effects of anisotropy and external gravitation by a massive central object (Bettwieser et al., 1984).

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Jiang, Qing Quan. "The Hawking Radiation of the Charged Massive Particle via Tunneling from a Plane Symmetry Black Hole." Applied Mechanics and Materials 170-173 (May 2012): 2940–43. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.2940.

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In Anti-de Sitter space-time, we develop the Parikh-Wilczek’s semi-classical quantum tunneling method to investigate the Hawking radiation of the charged massive particle via tunneling from a plane symmetry black hole. The result shows that, when taking self-gravitation interaction into account, the tunneling rate of the charged massive particle is related to the change of Bekenstein-Hawking entropy, and that the exact emission spectrum is not strictly pure thermal, but is consistent with the underlying unitary theory.

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Chugreev, Yu V. "A benign property of the ghost mode in massive theory of gravitation." Physics of Particles and Nuclei Letters 15, no. 1 (January 2018): 43–48. http://dx.doi.org/10.1134/s1547477118010053.

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Nesbet, Robert K. "Conformal Higgs model: Gauge fields can produce a 125 GeV resonance." Modern Physics Letters A 36, no. 22 (July 20, 2021): 2150161. http://dx.doi.org/10.1142/s0217732321501613.

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Recent cosmological observations and compatible theory offer an understanding of long-mysterious dark matter and dark energy. The postulate of universal conformal local Weyl scaling symmetry, without dark matter, modifies action integrals for both Einstein–Hilbert gravitation and the Higgs scalar field by gravitational terms. Conformal theory accounts for both observed excessive external galactic orbital velocities and for accelerating cosmic expansion. SU(2) symmetry-breaking is retained by the conformal scalar field, which does not produce a massive Higgs boson, requiring an alternative explanation of the observed LHC 125 GeV resonance. Conformal theory is shown here to be compatible with a massive neutral particle or resonance [Formula: see text] at 125 GeV, described as binary scalars [Formula: see text] and [Formula: see text] interacting strongly via quark exchange. Decay modes would be consistent with those observed at LHC. Massless scalar field [Formula: see text] is dressed by the [Formula: see text] field to produce Higgs Lagrangian term [Formula: see text] with the empirical value of [Formula: see text] known from astrophysics.

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ALDAYA, V., and E. SÁNCHEZ-SASTRE. "GAUGE THEORIES OF GRAVITY AND MASS GENERATION." International Journal of Geometric Methods in Modern Physics 05, no. 02 (March 2008): 197–232. http://dx.doi.org/10.1142/s0219887808002710.

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The compensating Utiyama's method including space-time symmetries is revisited as well as the gauge gravitational theories associated with translation, Poincaré and Weyl groups. Then we propose an extension of the gauge symmetry, allowing for the incorporation of the gauge group parameters into the theory as dynamical fields by considering the jet-gauge group as fundamental symmetry. As a consequence, a natural mass-generating mechanism for the gauge potentials arises without damaging gauge invariance. We also present, as a simple example, some sort of generalized Stueckelberg model for the Weyl group, thus accounting for massive dilatonic gauge field. Finally, the standard diffeomorphism symmetry of gravitation is extended by resorting to the jet-diffeomorphism group, formalism which helps to fix the Hilbert-Einstein Lagrangian in the teleparallelism version.

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Arminjon, Mayeul, and Rainer Wolfgang Winkler. "Motion of a Test Particle According to the Scalar Ether Theory of Gravitation and Application to its Celestial Mechanics." Zeitschrift für Naturforschung A 74, no. 4 (April 24, 2019): 305–16. http://dx.doi.org/10.1515/zna-2018-0470.

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AbstractThe standard interpretations of special relativity (Einstein–Minkowski) and general relativity (GR) lead to a drastically changed notion of time: the eternalism or block universe theory. This has strong consequences for our thinking about time and for the development of new fundamental theories. It is therefore important to check this thoroughly. The Lorentz–Poincaré interpretation, which sees the relativistic effects as following from a “true” Lorentz contraction of all objects in their motion through the ether, uses a conservative concept of time and is in the absence of gravitation indistinguishable from the standard interpretation; but there exists currently no accepted gravitation theory for it. The scalar ether theory of gravitation is a candidate for such a theory; it is presented and discussed. The equations of motion for a test particle are derived; the case of a uniformly moving massive body is discussed and then specialized to the case of spherical symmetry. Formulas for the acceleration of test particles are given in the preferred frame of the ether and in the rest frame of the massive body that moves with velocityVwith respect to the ether. When the body rests in the ether (V=0), the acceleration is up to orderc−2identical to GR. The acceleration of a test particle forV≠0is given; this makes it possible to fit observations in celestial mechanics to ephemerides withVas a free parameter. The current status of such fits (although to ephemerides and not to observations) is presented and discussed.

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Rivera, Paul Cadelina. "The Theoretical Value of the Hubble Constant Ho and Unification of the Fundamental Forces of Nature." European Journal of Applied Physics 3, no. 4 (July 21, 2021): 17–24. http://dx.doi.org/10.24018/ejphysics.2021.3.4.88.

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The Hubble constant Ho represents the speed of expansion of the universe and various cosmological observations and modeling methods were utilized by astronomers for a century to pin down its exact value. Determining Ho from cosmological observations is a long and tedious process requiring highly accurate datasets. To circumvent this need, a simple theoretical approach is introduced in this study which uses the concept of gravitational weakening and seismic-induced recession. As tremors occur among celestial objects, their gravitational fields would also change. This resulted in a fundamental relation of Ho and the computed rate of recession that gives a theoretical value for Ho=69.921 Km/s/Mpc. Using the newly discovered seismic-induced gravitational weakening and time dilation, it is possible that various astrophysical methods using different measurement methods would converge to this theoretical Ho value when cosmological distances and time delay measurements are corrected with the simple formulas we derived. The new model assumes that, as quakes occur in celestial objects, luminosity-induced acceleration and high-energy collision of protons and electrons may produce a massive number of neutrinos, quarks and other subatomic particles. Furthermore, the fine structure constant was found to be inversely proportional to Ho-squared and that the fine-structure constant obtained in this study gives a new physical interpretation of α. New relations for the speed of light, orbital velocity, gravitational force and the Hubble constant were further derived from the new recession constant using approximate relations for the Newtonian and electric force constant. This resulted in a modified gravitational law that is both repulsive and attractive and a theoretical explanation of the phenomenon of light-induced gravitation analogous to the electromagnetic force where photon is the force-carrier. Finally, the fundamental forces of gravitation, electromagnetism and strong nuclear force are now unified.

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Friedman, Yaakov. "Relativistic Gravitation Based on Symmetry." Symmetry 12, no. 1 (January 20, 2020): 183. http://dx.doi.org/10.3390/sym12010183.

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We present a Relativistic Newtonian Dynamics ( R N D ) for motion of objects in a gravitational field generated by a moving source. As in General Relativity ( G R ), we assume that objects move by a geodesic with respect to some metric, which is defined by the field. This metric is defined on flat lab spacetime and is derived using only symmetry, the fact that the field propagates with the speed of light, and the Newtonian limit. For a field of a single source, the influenced direction of the field at spacetime point x is defined as the direction from x to the to the position of the source at the retarded time. The metric depends only on this direction and the strength of the field at x. We show that for a static source, the R N D metric is of the same form as the Whitehead metric, and the Schwarzschild metric in Eddington–Finkelstein coordinates. Motion predicted under this model passes all classical tests of G R . Moreover, in this model, the total time for a round trip of light is as predicted by G R , but velocities of light and object and time dilation differ from the G R predictions. For example, light rays propagating toward the massive object do not slow down. The new time dilation prediction could be observed by measuring the relativistic redshift for stars near a black hole and for sungrazing comets. Terrestrial experiments to test speed of light predictions and the relativistic redshift are proposed. The R N D model is similar to Whitehead’s gravitation model for a static field, but its proposed extension to the non-static case is different. This extension uses a complex four-potential description of fields propagating with the speed of light.

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BARSHAY, SAUL, and GEORG KREYERHOFF. "LONG-RANGE INTERACTIONS BETWEEN DARK-MATTER PARTICLES IN A MODEL WITH A COSMOLOGICAL, SPONTANEOUSLY-BROKEN CHIRAL SYMMETRY." Modern Physics Letters A 20, no. 15 (May 20, 2005): 1155–60. http://dx.doi.org/10.1142/s0217732305017329.

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In a cosmological model with a chiral symmetry, there are two, dynamically-related spin-zero fields, a scalar ϕ and a pseudoscalar b. These fields have self-interactions. Spontaneous symmetry breaking results in a very massive scalar particle with mϕ≅5×1011 GeV , and a nearly massless, (Goldstone-like) pseudoscalar particle with 0<mb≲2.7×10-6 eV . One or both particles can be part of dark matter. There are coherent long-range interactions (at range ~ 1/mb≳10 cm ), from exchange of a b particle between a pair of b particles, a pair of ϕ particles, and between a ϕ and a b. We compare the strength of potentials for the different pairs to the corresponding gravitational potentials (within the same range ~ 1/mb), and show that the new force dominates between a b pair, that gravitation dominates between a ϕ pair, and that the potentials are comparable for a ϕ-b pair. The new interaction strength between a b pair is comparable to the gravitational interaction between a ϕ pair; its possibly greater coherent effect originates in the possibility that the number density of a very light b can be greater than that of a massive ϕ. We consider these results in the context of recent speculations concerning possible effects of special forces between dark-matter particles on certain galactic, and inter-galactic, properties.

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Jiang, Qing Quan. "The Quantum Effect of Massive Particles via Tunneling from the Einsein-Born-Infeld Black Hole." Advanced Materials Research 512-515 (May 2012): 926–30. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.926.

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Hawking radiation of massive particles via tunneling from the stationary axial symmetric Einsein-Born-Infeld black hole is studied. The result shows that, when self-gravitation interaction is considered, the exact spectrum is not precisely thermal, but satisfies the unitary theory. In special case, we also reduce the result to obtain the Hawking effect via tunneling from the Schwarzschild, Kerr and Kerr-Newman black hole.

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Manchester, R. N. "Pulsars and gravity." International Journal of Modern Physics D 24, no. 06 (April 27, 2015): 1530018. http://dx.doi.org/10.1142/s0218271815300189.

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Pulsars are wonderful gravitational probes. Their tiny size and stellar mass give their rotation periods a stability comparable to that of atomic frequency standards. This is especially true of the rapidly rotating "millisecond pulsars" (MSPs). Many of these rapidly rotating pulsars are in orbit with another star, allowing pulsar timing to probe relativistic perturbations to the orbital motion. Pulsars have provided the most stringent tests of theories of relativistic gravitation, especially in the strong-field regime, and have shown that Einstein's general theory of relativity is an accurate description of the observed motions. Many other gravitational theories are effectively ruled out or at least severely constrained by these results. MSPs can also be used to form a "Pulsar Timing Array" (PTA). PTAs are Galactic-scale interferometers that have the potential to directly detect nanohertz gravitational waves from astrophysical sources. Orbiting super-massive black holes in the cores of distant galaxies are the sources most likely to be detectable. Although no evidence for gravitational waves has yet been found in PTA data sets, the latest limits are seriously constraining current ideas on galaxy and black-hole evolution in the early universe.

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Ritter, Patxi, Sofiane Aoudia, Alessandro D. A. M. Spallicci, and Stéphane Cordier. "Indirect (source-free) integration method. I. Wave-forms from geodesic generic orbits of EMRIs." International Journal of Geometric Methods in Modern Physics 13, no. 02 (January 26, 2016): 1650021. http://dx.doi.org/10.1142/s0219887816500213.

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The Regge–Wheeler–Zerilli (RWZ) wave-equation describes Schwarzschild–Droste black hole perturbations. The source term contains a Dirac distribution and its derivative. We have previously designed a method of integration in time domain. It consists of a finite difference scheme where analytic expressions, dealing with the wave-function discontinuity through the jump conditions, replace the direct integration of the source and the potential. Herein, we successfully apply the same method to the geodesic generic orbits of EMRI (Extreme Mass Ratio Inspiral) sources, at second order. An EMRI is a Compact Star (CS) captured by a Super-Massive Black Hole (SMBH). These are considered the best probes for testing gravitation in strong regime. The gravitational wave-forms, the radiated energy and angular momentum at infinity are computed and extensively compared with other methods, for different orbits (circular, elliptic, parabolic, including zoom-whirl).

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JOSHI, PANKAJ S., and DANIELE MALAFARINA. "RECENT DEVELOPMENTS IN GRAVITATIONAL COLLAPSE AND SPACETIME SINGULARITIES." International Journal of Modern Physics D 20, no. 14 (December 31, 2011): 2641–729. http://dx.doi.org/10.1142/s0218271811020792.

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It is now known that when a massive star collapses under the force of its own gravity, the final fate of such a continual gravitational collapse will be either a black hole or a naked singularity under a wide variety of physically reasonable circumstances within the framework of general theory of relativity. The research of recent years has provided considerable clarity and insight on stellar collapse, black holes and the nature and structure of spacetime singularities. We discuss several of these developments here. There are also important fundamental questions that remain unanswered on the final fate of collapse of a massive matter cloud in gravitation theory, especially on naked singularities which are hypothetical astrophysical objects and on the nature of cosmic censorship hypothesis. These issues have key implications for our understanding on black hole physics today, its astrophysical applications, and for certain basic questions in cosmology and possible quantum theories of gravity. We consider these issues here and summarize recent results and current progress in these directions. The emerging astrophysical and observational perspectives and implications are discussed, with particular reference to the properties of accretion disks around black holes and naked singularities, which may provide characteristic signatures and could help distinguish these objects.

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Takahashi, M. "8.12. MHD accretion in a black hole magnetosphere." Symposium - International Astronomical Union 184 (1998): 367–68. http://dx.doi.org/10.1017/s0074180900085259.

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To explain the activity of active galactic nuclei or compact X-ray sources, I consider a black hole magnetosphere in the center of these objects. The considering black hole magnetosphere is composed of a massive black hole with surrounding fluids and magnetic fields, and rotates rapidly. Because of the strong gravitation and the rapid rotation, both an accretion and a wind/jet would be generated from plasma sources (e.g., an accretion disk and its corona). The outgoing flow carries the angular momentum from the plasma source effectively, and then the accretion would go on stationary, releasing its gravitational energy. I assume that the magnetosphere is stationary and axisymmetric, and that the ideal MHD approximation is available for the streaming fluid. I discuss the thermal effects on MHD flows, and then I argue that the trans-fast MHD accretion solution can be broken by highly thermal effects.

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Poher, Claude, and Danielle Poher. "Quantum Model of Inertia - Predictions - Confirmations, Consequences for Gravitation into Galaxies, and LCDM Cosmology Models." Applied Physics Research 12, no. 4 (July 31, 2020): 8. http://dx.doi.org/10.5539/apr.v12n4p8.

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We propose a Quantum model of Inertia using two main hypotheses, (i) existence of a general isotropic flux of Quanta (named “Universons”, which differ from Gravitons), propagating at light velocity into the Universe, (ii) a very short time duration interaction of these Quanta with elementary massive matter particles, with temporary momentum transfer (really a 2π phase shift of the wave function). Model parameters values are obtained from observations. The natural flux has Random Fluctuations in intensity and in direction, predicted to be the cause of Gravitational acceleration, a model of Gravitation is deduced. Predictions of the two models are confirmed by free fall of cold Neutrons; and by strong electrons accelerations into superconducting devices. A supplementary Cosmological acceleration H0 c, from Universe expansion, is predicted and confirmed by Astronomical observations. Galaxies rotation velocities are predicted from quantum fluctuations and H0c effect, solving the enigma that required Cold Dark Matter mass hypothesis. The cosmological concordance model has therefore to be strongly modified, and the isotropic flux expansion could also explain observations without “Dark Energy”.

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Trippe, Sascha. "The “graviton picture”: a Bohr model for gravitation on galactic scales?" Canadian Journal of Physics 93, no. 2 (February 2015): 213–16. http://dx.doi.org/10.1139/cjp-2014-0158.

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Modified Newtonian dynamics (MOND) provides a successful description of stellar and galactic dynamics on almost all astronomical scales. A key feature of MOND is the transition function from Newtonian to modified dynamics, which corresponds to the empirical mass discrepancy–acceleration (MDA) relation. However, the functional form of the MDA relation does not follow from theory in a straightforward manner; in general, empirical MDA relations are inserted ad hoc into analyses of stellar dynamics. I revisit the possibility of gravity being mediated by massive virtual particles, gravitons. Under certain reasonable assumptions, the resulting “graviton picture” implies a MDA relation that is equivalent to the — empirical — “simple μ” function of MOND, which is in very good agreement with observations. I conclude that the “graviton picture” offers a simple description of gravitation on galactic scales, potentially playing a role for gravitation analogous to the role played by Bohr’s model for atomic physics.

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Bastien, Pierre, and Claude Lejeune. "New Results on the Coagulation Equation." Symposium - International Astronomical Union 115 (1987): 547. http://dx.doi.org/10.1017/s0074180900096388.

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In attempting to reproduce the initial stellar mass function, we solved analytically the coagulation equation with an explicit time dependence in the coagulation rate in order to simulate the gravitational collapse of the fragments upon themselves as they move within the progenitor cloud. Two separate cases have been studied, with and without a mass dependence in the coagulation rate. The solution show that (1) inclusion of self-gravitation is very important and can change the results to the point of preventing coalescence to work altogether, depending on the values of the two free parameters, (2) the precise form of the mass dependence of the coagulation rate is not of prime importance in most situations of astrophysical interest, and (3) coagulation alone is not sufficient to yield a realistic mass spectrum and fragmentation must also be taken into account. Coagulation is more efficient for massive fragments and fragmentation for the smaller ones. These results are applied to different regions: star clusters, associations, and starburst regions.

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Gritschneder, Matthias, T. Naab, F. Heitsch, and A. Burkert. "Triggered star formation in the environment of young massive stars." Proceedings of the International Astronomical Union 2, S237 (August 2006): 246–50. http://dx.doi.org/10.1017/s174392130700155x.

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AbstractRecent observations with the Spitzer Space Telescope show clear evidence that star formation takes place in the surrounding of young massive O-type stars, which are shaping their environment due to their powerful radiation and stellar winds. In this work we investigate the effect of ionising radiation of massive stars on the ambient interstellar medium (ISM): In particular we want to examine whether the UV-radiation of O-type stars can lead to the observed pillar-like structures and can trigger star formation. We developed a new implementation, based on a parallel Smooth Particle Hydrodynamics code (called IVINE), that allows an efficient treatment of the effect of ionising radiation from massive stars on their turbulent gaseous environment. Here we present first results at very high resolution. We show that ionising radiation can trigger the collapse of an otherwise stable molecular cloud. The arising structures resemble observed structures (e.g. the pillars of creation in the Eagle Nebula, M16, or the Horsehead Nebula, B33). Including the effect of gravitation we find small regions that can be identified as formation places of individual stars. We conclude that ionising radiation from massive stars alone can trigger substantial star formation in molecular clouds.

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Chen, Yingtian, Hui Li, and Mark Vogelsberger. "Effects of initial density profiles on massive star cluster formation in giant molecular clouds." Monthly Notices of the Royal Astronomical Society 502, no. 4 (February 25, 2021): 6157–69. http://dx.doi.org/10.1093/mnras/stab491.

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ABSTRACT We perform a suite of hydrodynamic simulations to investigate how initial density profiles of giant molecular clouds (GMCs) affect their subsequent evolution. We find that the star formation duration and integrated star formation efficiency of the whole clouds are not sensitive to the choice of different profiles but are mainly controlled by the interplay between gravitational collapse and stellar feedback. Despite this similarity, GMCs with different profiles show dramatically different modes of star formation. For shallower profiles, GMCs first fragment into many self-gravitation cores and form subclusters that distributed throughout the entire clouds. These subclusters are later assembled ‘hierarchically’ to central clusters. In contrast, for steeper profiles, a massive cluster is quickly formed at the centre of the cloud and then gradually grows its mass via gas accretion. Consequently, central clusters that emerged from clouds with shallower profiles are less massive and show less rotation than those with the steeper profiles. This is because (1) a significant fraction of mass and angular momentum in shallower profiles is stored in the orbital motion of the subclusters that are not able to merge into the central clusters, and (2) frequent hierarchical mergers in the shallower profiles lead to further losses of mass and angular momentum via violent relaxation and tidal disruption. Encouragingly, the degree of cluster rotations in steeper profiles is consistent with recent observations of young and intermediate-age clusters. We speculate that rotating globular clusters are likely formed via an ‘accretion’ mode from centrally concentrated clouds in the early Universe.

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Vlasov, A. A., and A. A. Logunov. "Impossibility of catastrophically strong contraction of a massive body in the relativistic theory of gravitation." Theoretical and Mathematical Physics 63, no. 1 (April 1985): 323–28. http://dx.doi.org/10.1007/bf01017832.

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MIRMAN, R. "POINCARÉ ZERO-MASS REPRESENTATIONS." International Journal of Modern Physics A 09, no. 01 (January 10, 1994): 127–56. http://dx.doi.org/10.1142/s0217751x94000066.

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The zero-mass, discrete-spin, finite-dimensional representations of the proper Poincaré group are discussed, using the nondecomposable — and so nonunitary — representations of the little group, SE(2); matrix elements are thus arbitrary functions. The physical meaning and significance of the results are emphasized. Matrices are not decomposable, so the bases are connections, not tensors, giving gauge invariance — a partial statement of Poincaré invariance for zero mass only. Gravitation, a zero-mass spin-2 field, obeys a nonlinear condition (unlike the zero-mass spin-1 electromagnetic A), the Bianchi identity, which follows from the nature of Γ, and its integrated form, the Einstein equations, resulting in a curvature of space. Gravitation must be and is nonlinear, and electromagnetism linear, because of restrictions on which massless objects can interact with massive ones, these resulting from the differences in their little groups. The nonlinear representation is equivalent to a curvature of space — which thus can be considered a consequence of nonlinearity.

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Rivera, Paul C. "Gravitational Weakening of Seismic Origin as a Driving Mechanism of Some Astronomical Anomalies." Applied Physics Research 11, no. 2 (February 22, 2019): 10. http://dx.doi.org/10.5539/apr.v11n2p10.

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The anomalous increase of the astronomical unit, the mysterious secular increase of the lunar eccentricity and the flyby anomaly are important issues of modern astronomy. This study aims to determine the effect of earthquakes on the origin of these anomalies. Based on conventional physics, we found the existence of earthquake-induced gravitational weakening within the earth-moon-sun system and beyond. New equations of gravitation, including time dilation, are introduced that can explain the anomalous increase of the astronomical unit and the lunar orbit. A modified equation that includes the effect of massive quakes also explains the anomalous increase of the lunar eccentricity. Furthermore, the results of the present study can explain the flyby and Pioneer anomalies experienced by spacecraft during gravity assisted maneuvers. A modification of the 3rd Law of Kepler is also presented. Implications on the elliptic orbit of the earth, its reduced velocity and the occurrence of leap years are also discussed. Using the seismic-induced gravitational weakening model, probable trigger mechanisms of the faint young sun paradox and the Allais effect are also presented. An estimate of the age of the earth based on the observed values of the Hubble parameter and the USGS earthquake data for the past century is also presented. A new model of the seismic-driven expanding universe and a new equation to determine the expansion rate of galaxies and the universe is also proposed. The sudden earth’s retreat due to gravitational weakening and its implication on anomalous astronomical refraction and flight risk at night especially near the equatorial region, and its effect on the abrupt satellite orbital decay, spin and drift are also discussed. This study may also shed light on the occurrence of sinkholes and massive landslides. Finally, this study proposes a new equation that can explain the observed changes in the fine structure constant.

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MASHHOON, BAHRAM. "BEYOND GRAVITOELECTROMAGNETISM: CRITICAL SPEED IN GRAVITATIONAL MOTION." International Journal of Modern Physics D 14, no. 12 (December 2005): 2025–37. http://dx.doi.org/10.1142/s0218271805008121.

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A null ray approaching a distant astronomical source appears to slow down, while a massive particle speeds up in accordance with Newtonian gravitation. The integration of these apparently incompatible aspects of motion in general relativity is due to the existence of a critical speed. The dynamics of particles moving faster than the critical speed could then be contrary to Newtonian expectations. Working within the framework of gravitoelectromagnetism, the implications of the existence of a critical speed are explored. The results are expected to be significant for high energy astrophysics.

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Sahu, R. C., B. Behera, and S. P. Misra. "Non-static plane symmetric massive string magnetized perfect fluid cosmological models in bimetric theory of gravitation." IOSR Journal of Mathematics 10, no. 5 (2014): 54–59. http://dx.doi.org/10.9790/5728-10555459.

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Journal articles on the topic 'Massive gravitation'

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