Gravitational waves in metric-affine gravity theory

Civita criticized Einstein’s papers on gravitational waves: their energy momentum is frame dependent and therefore does not fit the covariance of Einstein’s gravity theory. Infeld and Rosen did not believe gravitational waves existed, and Einstein changed his mind on their existence repeatedly. Others did believe in them, such as Fock and Feynman. Weber constructed his “Weber bar” to detect gravitational waves, but when he claimed success, he was criticized. He then proposed using a Michelson-Morley type of interferometer with lasers to detect gravitational waves, as did Weiss. Merging black holes and neutron stars were proposed as detectable sources of gravitational waves. Taylor and Hulse, using the large Arecibo radio telescope, indirectly detected gravitational waves from inspiraling neutron stars. Primordial gravitational waves, still emanating from the Big Bang, were claimed to have been detected by BICEP2, but the waves were eventually shown to be a result of foreground dust.

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FLUCTUATION SPECTRUM FROM A SCALAR-TENSOR BIMETRIC GRAVITY THEORY

International Journal of Modern Physics D ◽

10.1142/s0218271803003098 ◽

2003 ◽

Vol 12 (04) ◽

pp. 697-712 ◽

Cited By ~ 6

Author(s):

M. A. CLAYTON ◽

J. W. MOFFAT

Keyword(s):

Scalar Field ◽

Gravitational Waves ◽

Early Universe ◽

Initial Period ◽

Field Potential ◽

Gravity Theory ◽

Fluctuation Spectrum ◽

Quadratic Potential ◽

Initial Values ◽

Bimetric Gravity

Predictions of the CMB spectrum from a bimetric gravity theory (BGT)1 are presented. The initial inflationary period in BGT is driven by a vanishingly small speed of gravitational waves vg in the very early universe. This initial inflationary period is insensitive to the choice of scalar field potential and initial values of the scalar field. After this initial period of inflation, vg will increase rapidly and the effects of a potential will become important. We show that a quadratic potential introduced into BGT yields an approximately flat spectrum with inflation parameters: ns=0.98, nt=-0.027, αs=-3.2×10-4 and αt=-5.0×10-4, with r ≥ 0.014.

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MASSIVE GRAVITATIONAL WAVES FROM THE R2 THEORY OF GRAVITY: PRODUCTION AND RESPONSE OF INTERFEROMETERS

International Journal of Modern Physics A ◽

10.1142/s0217751x08038603 ◽

2008 ◽

Vol 23 (10) ◽

pp. 1521-1535 ◽

Cited By ~ 34

Author(s):

CHRISTIAN CORDA

Keyword(s):

Dark Matter ◽

Gravitational Waves ◽

Longitudinal Force ◽

High Order ◽

Gravity Theory ◽

Theory Of Gravity ◽

Gravity Theories ◽

The Universe

We show that from the R2 high order gravity theory it is possible to produce, in the linearized approach, particles which can be seen as massive modes of gravitational waves (GW's). The presence of the mass generates a longitudinal force in addition of the transverse one which is proper of the massless gravitational waves and the response an interferometer to the effect is computed. This could be, in principle, important to discriminate among the gravity theories. The presence of the mass could also have important applications in cosmology because the fact that gravitational waves can have mass could give a contribution to the dark matter of the Universe.

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Gravitational Waves in Scalar–Tensor–Vector Gravity Theory

Universe ◽

10.3390/universe7010009 ◽

2021 ◽

Vol 7 (1) ◽

pp. 9

Author(s):

Yunqi Liu ◽

Wei-Liang Qian ◽

Yungui Gong ◽

Bin Wang

Keyword(s):

Field Equation ◽

Vector Field ◽

Gravitational Waves ◽

Relative Motion ◽

Modified Gravity ◽

Gravity Theory ◽

Test Particles ◽

Stress Energy ◽

Self Gravity ◽

Perturbed Equation

In this paper, we study the properties of gravitational waves in the scalar–tensor–vector gravity theory. The polarizations of the gravitational waves are investigated by analyzing the relative motion of the test particles. It is found that the interaction between the matter and vector field in the theory leads to two additional transverse polarization modes. By making use of the polarization content, the stress-energy pseudo-tensor is calculated by employing the perturbed equation method. Additionally, the relaxed field equation for the modified gravity in question is derived by using the Landau–Lifshitz formalism suitable to systems with non-negligible self-gravity.

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Persamaan Gelombang Gravitasi untuk Teori Proca yang Digeneralisasi

Prosiding SNFA (Seminar Nasional Fisika dan Aplikasinya) ◽

10.20961/prosidingsnfa.v5i0.46604 ◽

2020 ◽

Vol 5 ◽

Author(s):

Marliana Marliana ◽

Agustina Widiyani ◽

Azwar Sutiono ◽

Agus Suroso ◽

Freddy P. Zen

Keyword(s):

Black Holes ◽

Vector Field ◽

Neutron Stars ◽

Gravitational Wave ◽

Gravitational Waves ◽

General Equation ◽

Direct Detection ◽

Gravity Theory ◽

Binary Black Holes ◽

Massive Vector

Abstract: The direct detection of gravitational waves from binary black holes and neutron stars have been taking a new oportunities to test teori of gravity.The gravitational wave is affected by the modification of a gravity theory during propagation at cosmological distances. By comparing general equation of gravtiational wave and modification of gravity theory, is obtained equation of gravitational wave for the generalized Proca theories. As a result, we find equation of gravitational wave for the generalized Proca theory. We conclude that the massive vector field affected propagation of gravitational wave. we can use the result to test the generalized Proca theory. Abstrak: Dengan terdeteksinya gelombang gravitasi secara langsung dari biner lubang hitam dan bintang neutron menjadi kesempatan untuk dapat menguji teori gravitasi yang sedang dikembangkan.Gelombang gravitasi secara umum dipengaruhi oleh modifikasi teori gravitasi selama penjalarannya pada jarak kosmologi. Dengan membandingkan persamaan gelombang gravitasi dengan teori modifikasi yang dikembangkan, diperoleh persamaan umum gelombang gravitasi dari teori gravitasi yang dikembangkan. Pada artikel ini diperoleh persamaan gelombang gravitasi untuk teori Proca yang digeneralisasi. Dapat disimpulkan bahwa fungsi yang mengandung vektor medan masif dapat mempengaruhi gelombang gravitasi. Persamaan ini dapat digunakan untuk menguji teori Proca yang digeneralisasi.

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