Zobrazeno 1 - 10
of 227
pro vyhledávání: '"Sayan, A"'
Autor:
Sen, Gargi, Chakraborty, Chandrachur, Bhattacharyya, Sudip, Maity, Debaprasad, Chakrabarti, Sayan, Das, Santabrata
The accreting collapsed object GRO J1655-40 could contain the gravitomagnetic monopole (GMM), and it was shown to be better described by the Kerr-Taub-NUT (KTN) spacetime instead of the Kerr spacetime. The warped accretion disk has also been observed
Externí odkaz:
http://arxiv.org/abs/2408.03270
Autor:
Dey, Ayan, Kar, Sayan
We study closed string evolution in the pp-wave spacetime assuming different pulse shapes (square and sech-squared) in the exact gravitational wave metric. It is shown that the shape of a circular closed string changes permanently to an elliptical fo
Externí odkaz:
http://arxiv.org/abs/2407.10095
Complete waveform models able to account for arbitrary non-planar orbits represent a holy grail in current gravitational-wave astronomy. Here, we take a step towards this direction and present a simple yet efficient prescription to obtain the evoluti
Externí odkaz:
http://arxiv.org/abs/2404.15408
Publikováno v:
Phys.Dark Univ. 44 (2024) 101472
We have investigated the characteristics of shadows cast by the Kerr black hole in the presence of plasma and compared them to those of a rotating wormhole in a uniform plasma space-time for an observer at infinity. Interestingly, for the same unifor
Externí odkaz:
http://arxiv.org/abs/2403.12439
Renormalization Group correction to General Relativity (RGGR) proposes a logarithmic running of the gravitational coupling $\left(G\right)$, resulting in a modified description of gravity. This has the potential to explain the observed kinematics of
Externí odkaz:
http://arxiv.org/abs/2403.00531
Autor:
Pal, Sayan Kumar, Nandi, Partha
Motivated by the symmetry in the non-relativistic limit of anti-de Sitter geometry, we employ planar dynamical models featuring exotic (deformed) harmonic oscillators, presented through direct and indirect Lagrangian representations. The latter intro
Externí odkaz:
http://arxiv.org/abs/2401.12957
Publikováno v:
Universe 10 (3), 122 (2024)
$\phi$CDM models provide an alternative to the standard $\Lambda$CDM paradigm, while being physically better motivated. These models lead to a time-dependent speed of sound for dark energy that is difficult to replicate by $w$CDM parametrizations. We
Externí odkaz:
http://arxiv.org/abs/2310.16911
Effect of temperature on measurement of fundamental constants using white dwarfs in Gaia-EDR3 survey
Publikováno v:
MNRAS 527 (2024) 232
Fundamental constants are crucial for comprehending physical mechanisms, but their measurements contain uncertainties due to experimental limitations. We investigate the impact of system temperature on these uncertainties using nearby white dwarfs ob
Externí odkaz:
http://arxiv.org/abs/2310.06050
Publikováno v:
Ann. Phys. 462, 169614 (2024)
This study explores spherically symmetric non-linear electrodynamics black holes and their effects on light propagation. We derive the governing metric, revealing radial coordinate dynamics within the event horizon. We analyze photon trajectories, fi
Externí odkaz:
http://arxiv.org/abs/2309.13680
Publikováno v:
Eur. Phys. J. Plus, 139:219 (2024)
We explore the characteristics of shadows for a general class of spherically symmetric, static spacetimes, which may arise in general relativity or in modified theories of gravity. The chosen line element involves a sum (with constant but different c
Externí odkaz:
http://arxiv.org/abs/2309.11383