Gravitational waves from an axi-symmetric source in the Nonsymmetric Gravitational Theory

Cornish, N.; Moffat, J. W.; Tatarski, D. C.

doi:10.1007/bf02113075

Cited by 6 publications

(3 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In 2002, Kostelecky and Mews (2002) used polarization measurements of light from cosmologically distant astrophysical sources to yield stringent constraints down to 2 × 10 -32 . The electromagnetic propagation in Moffat's nonsymmetric gravitational theory (Moffat 1991, Cornish et al 1995 fits the χ-g framework. Krisher (1991), and Haugan and Kauffmann (1995) have used the pulsar data and extragalactic radio observations to constrain it.…”

Section: Theoretical Frameworkmentioning

confidence: 96%

Searches for the role of spin and polarization in gravity

2010

Rep. Prog. Phys.

126

191

View full text Add to dashboard Cite

Spin is fundamental in physics. Gravitation is universal. Searches for the role of spin in gravitation dated before the firm establishment of the electron spin in 1925. Since mass and spin or helicity in the case of zero mass are the only invariants of the Poincaré group and mass participates in universal gravitation, these searches are natural steps to pursue. Here we review both the theoretical and experimental efforts in searching for the role of spin/polarization in gravitation. We discuss torsion, Poincaré gauge theories, teleparallel theories, metric-affine connection theories and pseudoscalar (axion) theories. We discuss laboratory searches for electron and nucleus spin-couplings ---the weak equivalence principle experiments for polarized-bodies, the finite-range spin-coupling experiments, the spin-spin coupling experiments and the cosmic-spin coupling experiments. The role played by angular momentum and rotation is explicitly discussed. We discuss astrophysical and cosmological searches for photon polarization coupling. Investigation in the implications and interrelations of equivalence principles led to a possible pseudoscalar or vector interaction, and led to the proposal of WEP II (Weak Equivalence Principle II) which include rotation in the universal free-fall motion. Evidences for WEP II are discussed and compiled.Cosmological searches for photon-polarization coupling test the possibility of violation of EEP and the existence of cosmic pseudoscalor/vector interaction and may reveal a potential influence to our presently-observed universe from a larger arena. In relativistic gravity, there is a Lense-Thirring frame-dragging on rotating body with angular momentum. In analog with gyromagnetic ratio in electromagnetism, one can define gyrogravitational ratio. A profound search for the role of spin in gravitation is to measure the gyrogravitational ratio of particles. This could lead us to probe and understand the microscopic origins of gravity. We discuss the strategies to perform such experiments. R. Acad. Sci., Paris 174 593 Cartan É 1923 Sur les variétés à connexion affine et la théorie de la relativitée généralisée I, Ann. Ec. Norm. Sup. 40, 325 Cartan É 1924 Sur les variétés à connexion affine et la théorie de la relativitée généralisée I (suite), Ann. Ec. Norm. Sup. 41 1 Cartan É 1925 Sur les variétés à connexion affine et la théorie de la relativitée généralisée II, Ann. Ec. Norm. Sup. 42 17 Carroll S M, Field G B and Jackiw R 1990 Limits on a Lorentz-and parity-violating modification of electrodynamics Phys. Rev. D 41 1231-1240 Carroll S M and Field G B 1991 Einstein equivalence principle and the polarization of radio galaxies A experiment to search for vacuum dichroism, pseudoscalar-photon interaction and millicharged fermions Mod. Phys. Lett. A 22 2815 [arXiv:hep-ex/0611050v1] Cheng H-C, Luty M A, Mukohyama and Thaler J 2006 Spontaneous Lorentz breaking at high energies J High Energy Phys. 0605 076 Cheng K-S and Ni W-T 1980 Conditions for the local existence of metric in a generic affine manifo...

show abstract

Section: Theoretical Frameworkmentioning

confidence: 96%

Searches for the role of spin and polarization in gravity

2010

Rep. Prog. Phys.

126

191

View full text Add to dashboard Cite

show abstract

“…In 2002, Kostelecky and Mews [70] used polarization measurements of light from cosmologically distant astrophysical sources to yield stringent constraints down to 2 × 10 -32 . The electromagnetic propagation in Moffat's nonsymmetric gravitational theory [71,72] fits the χ-g framework. Krisher [73], and Haugan and Kauffmann [58] have used the pulsar data and extragalactic radio observations respectively to constrain it.…”

Section: Nonbirefringence Condition For the Skewonless Casementioning

confidence: 99%

Equivalence principles, spacetime structure and the cosmic connection

2017

One Hundred Years of General Relativity

View full text Add to dashboard Cite

After reviewing the meaning of various equivalence principles and the structure of electrodynamics, we give a fairly detailed account of the construction of the light cone and a core metric from the equivalence principle for the photon (no birefringence, no polarization rotation and no amplification/attenuation in propagation) in the framework of linear electrodynamics using cosmic connections/observations as empirical support. The cosmic nonbirefringent propagation of photons independent of energy and polarization verifies the Galileo Equivalence Principle [Universality of Propagation] for photons/electromagnetic wave packets in spacetime. This nonbirefringence constrains the spacetime constitutive tensor to high precision to a core metric form with an axion degree and a dilaton degree of freedom. Thus comes the metric with axion and dilation. Constraints on axion and dilaton from astrophysical/cosmic propagation are reviewed. Eötvös-type experiments, Hughes-Drever-type experiments, redshift experiments then constrain and tie this core metric to agree with the matter metric, and hence a unique physical metric and universality of metrology. We summarize these experiments and review how the Galileo equivalence principle constrains the Einstein Equivalence Principle (EEP) theoretically. In local physics this physcical metric gives the Lorentz/Poincaré covariance. Understanding that the metric and EEP come from the vacuum as a medium of electrodynamics in the linear regime, efforts to actively look for potential effects beyond this linear scheme are warranted. We emphasize the importance of doing Eötvös-type experiments or other type experiments using polarized bodies/polarized particles. We review the theoretical progress on the issue of gyrogravitational ratio for fundamental particles and update the experimental progress on the measurements of possible long range/intermediate range spin-spin, spin-monopole and spincosmos interactions.

show abstract

“…[18]). In NGT (Nonsymmetric Gravitation Theory) the problem of gravitational radiation from axisymmetric sources has been taken into account (see Refs [19], [20], [21]).…”

Section: Introductionmentioning

confidence: 99%