Constraints on spacetime anisotropy and Lorentz violation from the GRAAL experiment

Chang, Zhe; Wang, Sai

doi:10.1140/epjc/s10052-013-2337-6

Cited by 12 publications

(28 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All this phenomenology and cosmological constraints combined with particular QG theories where the effective geometry is Finslerian can give a better insight about LV and the colorful morphology of the physical manifold. This detailed and complicated analysis is an intriguing open challenge (for some recent studies see [91][92][93][94][95][96][153][154][155][156][157][158][159][160]). Since our amplification mechanism strongly depends on the intensity of Cartan tensor and its evolution in time, constraining the 'Finslerity' of space-time may lead to a better understanding of why our universe is magnetized.…”

Section: Discussionmentioning

confidence: 99%

Cosmic magnetization in curved and Lorentz violating space–times

Kouretsis

2014

Eur. Phys. J. C

View full text Add to dashboard Cite

The presence of the large-scale magnetic fields is one of the greatest puzzles of contemporary cosmology. The symmetries of the electromagnetic field theory combined with the geometric structure of the FRW universe leads to an adiabatic decay of the primordial magnetic fields. Due to this rapid decay the residual large-scale magnetic field is astrophysically unimportant. A common feature among many of the proposed amplification mechanisms is the violation of Lorentz symmetries. We introduce an amplification mechanism within a Lorentz violating environment where we use Finsler geometry as our theoretical background. The mechanism is based on the adoption of a local anisotropic structure that leads to modifications on the Ricci identities. Thus, the wave-like equation of any vector source, including the magnetic field, is enriched by the Finslerian curvature theory. In particular limits, the remaining seed field can be strong enough to seed the galactic dynamo. In our analysis we also develop the 1+3 covariant formalism for the 4-vector potential in curved space-times.

show abstract

Section: Discussionmentioning

confidence: 99%

Cosmic magnetization in curved and Lorentz violating space–times

Kouretsis

2014

Eur. Phys. J. C

View full text Add to dashboard Cite

show abstract

“…[30]. This model suggested that the spacetime of very early universe may be of Randers-Finsler type.…”

Section: Primordial Power Spectra With Anisotropymentioning

confidence: 96%

“…We are only interested in the evolution of the very early universe. After our calculation of the connection and the curvature tensor, Einstein's gravitational equation could be obtained as [30,50] …”

Section: Primordial Power Spectra With Anisotropymentioning

confidence: 99%

“…However, it is possible that A ij (ℓ) has no preferred directions when the statistical anisotropy has certain particular behaviors. For instance, the initial power spectrum P R (k) may acquire a dipolar modulation [29,30]. The two-point correlators could reduce to the isotropic form, since a dipole is point-parity asymmetric, see .…”

Section: The "Power Tensor" Techniquementioning

confidence: 99%

“…Here φ (0) (t) denotes the zero-order part which drives the inflation. The 00 component of Einstein's gravitational equation gives the Friedmann equation [30] …”

Section: Primordial Power Spectra With Anisotropymentioning

confidence: 99%

See 2 more Smart Citations

Quadrupole-octopole alignment of CMB related to the primordial power spectrum with dipolar modulation in anisotropic spacetime

Chang

Wang

2015

Chinese Phys. C

Self Cite

View full text Add to dashboard Cite

The WMAP and Planck observations show that the quadrupole and octopole orientations of the CMB might align with each other. We reveal that the quadrupole-octopole alignment is a natural implication of the primordial power spectrum in an anisotropic spacetime. The primordial power spectrum is presented with a dipolar modulation. We obtain the privileged plane by employing the "power tensor" technique. At this plane, there is the maximum correlation between quadrupole and octopole. The probability for the alignment is much larger than what in the isotropic universe. We find that this model would lead to deviations from the statistical isotropy only for low-ℓ multipoles.a

show abstract

Finsler geometric perspective on the bulk flow in the universe

Chang

Wang

2013

Physics Letters B

Self Cite

View full text Add to dashboard Cite

Astronomical observations showed that there may exist a bulk flow with peculiar velocities in the universe, which contradicts with the (\Lambda)CDM model. The bulk flow reveals that the observational universe is anisotropic at large scales. In fact, a more reliable observation on the anisotropy of spacetime comes from the CMB power spectra. The WMAP and Planck satellites both show that there is a hemispherical power asymmetry at large-angular scales. In this paper, we propose a "wind" scenario to the bulk flow (or the anisotropy of spacetime). Under the influence of the "wind", the spacetime metric could become a Finsler structure. By resolving the null geodesic equation, we obtain the modified luminosity distance, which has a dipolar form at the leading order. Thus, the "wind" describes well the bulk flow. In addition, we perform a least-(\chi^2) fit to the data of type Ia supernovae (SNe Ia) in the Union2.1 compilation. The peculiar velocity of the bulk flow has an upper limit (v_{bulk}\lesssim 4000 \rm{km/s}), which is compatible with all the existing observational values.Comment: 11 pages, no figure. To be published in the PL

show abstract

Constraints on spacetime anisotropy and Lorentz violation from the GRAAL experiment

Cited by 12 publications

References 36 publications

Cosmic magnetization in curved and Lorentz violating space–times

Cosmic magnetization in curved and Lorentz violating space–times

Quadrupole-octopole alignment of CMB related to the primordial power spectrum with dipolar modulation in anisotropic spacetime

Finsler geometric perspective on the bulk flow in the universe

Contact Info

Product

Resources

About