arXiv subjects

Moninder Singh Modgil

Publications and source records attributed to Moninder Singh Modgil.

15 recordsLinked to original sources

arXiv2010

Interplay between the small and the large scale structure of spacetime

Existence of frame invariant, maximum, time interval $T$, length $L$, and mass $M$ is postulated. In the de Sitter universe - (1) the life span of universe, (2) the circumference of universe at the point of maximum expansion, and (3) the mass of the universe - are candidates for $T$, $L$ and $M$ respectively. Impact of such invariant global parameters, on the definition of local physical quantities, such as velocity is discussed.

physics.gen-ph↗

arXiv2009

Loschmidt's paradox, entropy and the topology of spacetime

The issue of the "eternal return" is examined from the perspective of the topology of spacetime. Constraints on dynamical laws for the periodic evolution of a system or universe are highlighted. Using a Fourier series expansion, an infinite set of simultaneous linear equations is formulated for the periodic evolution of a system/universe.

gr-qc↗

arXiv2009

Use of Gödel Universe to Construct A New Zollfrei Metric with $R^2 \times S^1$ Topology

A new example of $(2+1)$-dimensional Zollfrei metric, with the topology $R^2 \times S^1 $, is presented. This metric is readily obtained from the celebrated $(3+1)$- dimensional rotating Gödel universe $G_{3,1}$. This is because $G_{3,1}$ has the interesting property that, the light rays which are confined to move on the plane perpendicular to the rotation axis, return to their origin after a time period $T = \frac{2 π}ω[\sqrt{2}-1]$ -where $ω$ is the angular velocity of the universe. Hence by - the topological identification of pairs of points on the time coordinate, seperated by the time interval $T$. and droping the flat $x_3$ coordinate - which is directed along the rotation axis; one obtains the $(2+1)$-dimensional Zollfrei metric with the $R^2 \times S^1$ topology.

physics.gen-ph↗

arXiv2008

Climate Control Using Nuclear Energy

We examine implications of anthropogenic low pressure regions, - created by injecting heat from nuclear reactors, into atmosphere. We suggest the possibility that such artificially generated low pressure regions, near hurricanes could disrupt their growth, path, and intensity. This method can also create controlled tropical stroms, which lead to substantial rainfall in arid areas, such as - (1)Sahara desert, (2) Australian interior desert, and (3) Indian Thar desert. A simple vortex suction model is developed to study, effect on atmospheric dynamics, by such a nuclear heat injection system.

physics.gen-ph↗

arXiv2007

Geometry of Time, Axiom of Choice and Neuro-Biological Quantum Zeno Effect

Role of axiom of choice in quantum measurement is highlighted by suggesting that the conscious observer chooses the outcome from a mixed state. Further, in a periodically repeating universe, these outcomes must be pre-recorded within the non-physical conscious observers, which precludes free will. Free will however exists in a universe with open time, It is suggested that psychology's binding problem is connected with Cantor's original definition of set. Influence of consciousness on material outcome through quantum processes is discussed and interesting constraints derived. For example, it is predicted that quantum mechanical brain states should get frozen if monitored at sufficiently small space-time intervals - a neuro-biological version of the so called quantum zeno effect, which has been verified in domain of micro-physics. Existence of a very small micro-mini-black-hole in brain is predicted as a space-time structural interface between consciousness and brain, whose vaporization explains mass-loss reported in weighing experiments, conducting during the moments of death.

physics.gen-ph↗

arXiv2006

The Gödel Universe: A Practical Travel Guide

We study the Gödel universe through worldlines associated with motion at constant speed and constant acceleration orthogonal to the instantaneous velocity (WSAs). We show that these worldlines can be used to access every region -- both spatial and temporal -- of the space-time. We capture the insights they accord in a series of sketches, which extend significantly the Hawking and Ellis picture of the Gödel universe.

gr-qc↗

arXiv2005

Recurrence Metrics and Time Varying Light Cones

It is shown by explicit construction of new metrics, that General Relativity can solve the exact Poinc$\acute{a}$re recurrence problem. In these solutions, the light cone, flips periodically between past and future, due to a periodically alternating arrow of the proper time. The geodesics in these universes show periodic Loschmidt's velocity reversion $v \to -v$, at critical points, which leads to recurrence. However, the matter tensors of some of these solutions exhibit unusual properties - such as, periodic variations in density and pressure. While this is to be expected in periodic models, the physical basis for such a variation is not clear. Present paper therefore can be regarded as an extension of Tipler's "no go theorem for recurrence in an expanding universe", to other space-time geometries.

gr-qc↗

arXiv2005

Godel Type Metrics in Randall Sundrum Model

Anisotropic cosmological models such as the Gödel universe and its extensions - Gödel type solutions, are embedded on a visible 3-brane in the Randall-Sundrum 1 model. The size of the extra dimension is stabilized by tuning the rotation parameter to a very small value so that hierarchy problem can be solved. A limiting case also yields the Randall-Sundrum 2 model. The rotation parameter on the visible brane turns out to be of order $10^{-32}$, which implies that visible brane essentially lacks rotation.

gr-qc↗

arXiv2005

Epistemology in Cyclic Time

Consider the scenario, in which human civilization undergoes periodic eras of progression and regression, and consequently, changes in cosmological knowledge are cyclic. There exist solutions of general theory of relativity, such as the Gödel universe, in which the cosmos is rotating. If the real universe is indeed rotating, than this would be a reversion to rotating universe models, used in ancient cosmological models. We argue that such reversions in physical models would be inevitable in a space-time in which time is having $S^1$ (circular) topology.

physics.gen-ph↗

arXiv2004

Curvature effects in special relativity

Space-time measurements, of gedanken experiments of special relativity need modification in curved spaces-times. It is found that in a space-time with metric $g$, the special relativistic factor $γ$, has to be replaced by $γ_\g=1/sqrt{g{μν} V^μV^ν}$, where $V_μ=(1,v,0,0)$, is the 4-velocity, and $v$ the relative velocity between the two frames. Examples are given for Schwarzschild metric, Friedmann-Robertson-Walker metric, and the Gödel metric. Among the novelties are paradoxical tachyonic states, with $γ_\g$ becoming imaginary, for velocities less than that of light, due to space-time curvature. Relativistic mass becomes a function of space-time curvature, $m=\sqrt{g_{μν}P^μP^ν}$, where $P_μ=(E,p)$ is the 4-momentum, signalling a new form of mach's principle, in which a global object - namely the metric tensor, is effecting interia.

physics.gen-ph↗

arXiv2004

Special Theory of Relativity in Curved Space Time

Space-time measurements, of gedanken experiments of special relativity need modification in curved spaces-times. It is found that in a space-time with metric $g$, the special relativistic factor $γ$, has to be replaced by $γ_g=1/\sqrt{g_{μν} V^μV^ν}$, where $V_μ=(1,v,0,0)$, is the 4-velocity, and $v$ the relative velocity between the two frames Examples are given for Schwarzschild metric, Friedmann-Robertson-Walker metric, and the Gödel metric. Among the novelties are paradoxical tachyonic states, with $γ_g$ becoming imaginary, for velocities less than that of light, due to space-time curvature. Relativistic mass becomes a function of space-time curvature, $m=\sqrt{g_{μν}P^μP^ν}$, where $P_μ=(E,p)$ is the 4-momentum, signaling a new form of Mach's principle, in which a global object - namely the metric tensor, is effecting interia.

physics.gen-ph↗

arXiv2002

The Quark Gluon Pion Plasma

While it is commonly believed that there is a {\it direct} transition from the hadronic to a quark gluon phase at high temperature, it would be prejudicial to rule out a sequence of dynamically generated intermediate scales. Using as guide, an effective lagrangian with unconfined gluons and constituent quarks, interacting with a chiral multiplet, we examine a scenario in which the system undergoes first-order transitions at $ T_{comp}$, the compositeness scale of the pions, at $T_χ$, the scale for spontaneous chiral symmetry breaking, and at $T_c$, the confinement temperature. We find that at current energies, it is likely that the formation temperature of the plasma, $ T_0 < T_{comp} $, and that this is therefore a quark gluon pion plasma (QGPP) rather than the usual quark gluon plasma (QGP). We propose some dilepton-related signatures of this scenario.

hep-ph↗

arXiv2002

Large Scale Weather Control Using Nuclear Reactors

It is pointed out that controlled release of thermal energy from fission type nuclear reactors can be used to alter weather patterns over significantly large geographical regions. (1) Nuclear heat creates a low pressure region, which can be used to draw moist air from oceans, onto deserts. (2) Creation of low pressure zones over oceans using Nuclear heat can lead to Controlled Cyclone Creation (CCC).(3) Nuclear heat can also be used to melt glaciers and control water flow in rivers.

physics.ao-ph↗

arXiv2001

Rotating Brane World Black Holes

A five dimensional rotating black string in a Randall-Sundrum brane world is considered. The black string intercepts the three brane in a four dimensional rotating black hole. The geodesic equations and the asymptotics in this background are discussed.

hep-th↗

arXiv2001

Recurrence metrics and the physics of closed time-like curves

We investigate vacuum solutions of Einstein's equation for a universe with an S^1 topology of time. Such a universe behaves like a time-machine and has geodesics which coincide with closed time-like curves (CTCs). A system evolving along a CTC experiences the Loschmidt velocity reversion and undergoes a recurrence commensurate with the universal period. We indicate why this universe is free of the causality paradoxes, usually associated with CTCs.

gr-qc↗