PARABOLOIDAL SPACE–TIMES AND RELATIVISTIC MODELS OF STRANGE STARS

2006 ◽  
Vol 15 (08) ◽  
pp. 1175-1182 ◽  
Author(s):  
KANTI JOTANIA ◽  
RAMESH TIKEKAR
Keyword(s):  
Space Time ◽  
Interior Space ◽  
Strange Stars ◽  
X Ray ◽  
Superdense Stars ◽  
Relativistic Models

The objective of this paper is to find out the suitability of an ansatz similar to that suggested by Vaidya–Tikekar, but prescribing paraboloidal geometry for the 3-space of the interior space–time of a relativistic spherical star in describing a family of physically viable models of superdense stars like Her X-1, SAX, and X-ray brust.

RELATIVISTIC SUPERDENSE STAR MODELS OF PSEUDO SPHEROIDAL SPACE–TIME

2005 ◽  
Vol 14 (06) ◽  
pp. 1037-1048 ◽  
Author(s):  
RAMESH TIKEKAR ◽  
KANTI JOTANIA
Keyword(s):  
Space Time ◽  
Compact Stars ◽  
Field Equations ◽  
Relativistic Field ◽  
Interior Space ◽  
Strange Matter ◽  
Superdense Stars ◽  
Star Models ◽  
Superdense Star ◽  
Spheroidal Geometry

The physically viable models of compact stars like SAX (J1808.4-3658) can be obtained using Vaidya–Tikekar ansatz prescribing spheroidal geometry for their interior space–time. We discuss here the suitability of an alternative ansatz in this context. The models of superdense star are proposed using a general three parameter family of solutions of relativistic field equations obtained adopting the alternative ansatz. The setup is shown to admit physically viable models of superdense stars and strange matter stars such as Her. X-1.

Electro-gravity spin density waves

2017 ◽  
Vol 14 (10) ◽  
pp. 1750146
Author(s):  
A. G. Syromyatnikov
Keyword(s):  
Shock Waves ◽  
Minkowski Space ◽  
Spin Density ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Space Time ◽  
Energy Output ◽  
Speed Of Light ◽  
X Ray ◽  
Cold Dust

It is known that some string models predict that strong bursts of gravitational radiation which should be detectable by LIGO, VIRGO and LISA detectors are accompanied by cosmologic gamma-ray bursts (GRBs). GRBs of low-energy gamma ray are associated with core-collapse supernovae (SN). However, measurements of the X-ray afterglow of very intense GRBs (allow a critical test of GRB theories) disagree with that predicted by widely accepted fireball internal–external shocks models of GRBs. It is also known that in a system of a large number of fermions, pairs of gravitational interaction occur on spontaneous breaking of the vacuum spatial symmetry, accompanied by gravitational mass defect. In another side, the space rays generation mechanism on a method of direct transformation of intergalactic gamma-rays to the proton current on spin shock-waves ensures precise agreement between generated proton currents (spin shock waves theory) with the angular distribution data of Galactic gamma-rays as well as for the individual pulses of gamma-/X-ray bursts. There is a precise confirmation of the generated currents (theory) with the burst radiation data characterized by the standard deviation of [Formula: see text] in intensity in relative units within the sensitivity of the equipment. Thus, it was found that the spin angular momentum conservation law (equation of dynamics of spin shock waves) in the X-ray/gamma ranges is fulfilled exactly in real time. The nature of gamma bursts is largely determined by the influence of powerful external sources. The angular distributions anisotropy of Galactic gamma rays and pulsars are determined by the paradoxes way, so this can only take place under conditions of the isotropy of space–time. In this regard, promising gravity in a Finsler space can have the selected direction in flat Minkowski space metric with torsion as in the Einstein–Cartan theory. Considering the induction of torsion in conformal transformations of tetrades (N-ades in arbitrary dimension N) under the Conformal Gauge Theory of Gravity (CGTG), here is considered an exact cosmological solution with Friedman’s asymptotic in the form of conformal flat Fock’s metrics at large times, describing the stage of decay on a cold dust-like medium of do-not-interacting-among-themselves particles and a light-like isotropic radiation. It is shown that at high times, indeed, the process of enlarging the space–time in the model metrics Friedman conformal is equivalent to Minkowski space with a gradient torsion trace in the CGTG Newtonian limit, accompanied by a polarization effect separation of electric charges induced by an electric field [Formula: see text] is manifested in the formation of plasma-like medium with a zero complete electric charge, that in the later stages of evolution is identical to the Fock’s model of a cold dust-like medium of do-not-interacting-among-themselves particles moving here with the same speed. The trace of torsion on the CGTG formula is freezing into an electromagnetic field spin tensor trace density and [Formula: see text] defined inside a spherical surface, moving at the speed of light, on which experiencing a gap. Therefore, this decision takes the form of an electro-gravity spin density wave, as performed in kinematic and dynamic close connection conditions for theorems on spin shock waves with spin flip at the front of the wave, moving at the speed of light in a vacuum. The theoretical dependence of electro-gravity wave energy output from the size of the emitting object is received. When applied to GRBs, this can give a new mechanism of nonthermal gamma rays production.

scholarly journals First Observation of an X-Ray Beam Following a New Geodesic When Gravitational Waves Deform Space-Time

2019 ◽  
Vol 11 (2) ◽  
pp. 53
Author(s):  
Edward Jiménez ◽  
Nicolás Recalde ◽  
Wilson P. Álvarez-Samaniego ◽  
Borys Álvarez-Samaniego ◽  
Douglas Moya-Álvarez ◽  
...  
Keyword(s):  
Gravitational Waves ◽  
Space Time ◽  
Treatment Center ◽  
X Rays ◽  
X Ray ◽  
Hardware Failure ◽  
Zero Position ◽  
Constant Polarization ◽  
Ray Trajectories ◽  
Log File

By using X-rays of a linear accelerator (LINAC Siemens X rays, 6 MeV) for medical use, we were able to measure gravitational waves, GW, (amplitude = 56:385mm, frequency =1 = 3Hz, velocity = c and polarization) and its threedimensional effect on X-ray trajectories. The collimated X-ray beam, which is in the plane (X; Y); travels on the Z axis at the speed of light in air and passing through the machine isocenter, until it reaches the target and, ultimate, is recorded in a radiographic film. Apparently, there is an exceptional coincidence in the operation of LINAC and the presence of GW. This coincidence occurred in VIRGINIA, GPS (38.634 351 1, -77.282 523 9), UTC (12/06/2011: 12: 56: 01). This important event, but not sui generis, was recorded in the LINAC computer system, on a film for radiography, in the log file of the cancer treatment center and it was reported to SIEMENS in order to try to find an explanation of a possible hardware failure, some abnormality or any software issue. The physicist and Siemens service engineer on site concluded that such event should never happened because LINAC was not malfunctioning. Consequently, for the X-rays, there was a deviation of the isocenter of the LINAC (△X = (11:5 ± 0:5)mm, △Y = (48 ± 0:5)mm), by the action of the amplitude of GW. The tolerance of a LINAC is lower than these measurements, and the equipment will stop working if they are greater than ±1:0mm for isocenter (zero position) and ±2:0mm for other collimator leaf positions. Therefore, this constitutes a register of space-time alteration with a consequent variation of the path of the X-ray beam. Finally, the registered gravitational waves leave invariant the angle between the axes (X; Y), of the X-ray beam, indicating a constant polarization.

Relativistic Models for Strange Stars in Massive Brans–Dicke Gravity

2021 ◽  
Vol 65 (10) ◽  
pp. 1048-1053
Author(s):  
M. Sharif ◽  
A. Majid
Keyword(s):  
Strange Stars ◽  
Relativistic Models

Space-time modulation of an X-ray beam by ultrasonic superlattice

1995 ◽  
Vol 42 (1) ◽  
pp. 127-134 ◽  
Author(s):  
D.V. Roshchupkin ◽  
I.A. Schelokov ◽  
R. Tucoulou ◽  
M. Brunel
Keyword(s):  
Space Time ◽  
X Ray ◽  
Time Modulation
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