Dynamics of a test null string in the gravitational field of a null string domain that radially changes its size

2020 ◽  
Vol 35 (02n03) ◽  
pp. 2040011 ◽  
Author(s):  
A. P. Lelyakov
Keyword(s):  
Gravitational Field ◽  
Initial Conditions ◽  
Rest Mass ◽  
Symmetric Domain ◽  
Life Time ◽  
Mass Energy ◽  
Axially Symmetric ◽  
Number Of Layers ◽  
External Conditions ◽  
Null String

The motion of a test null string “inside” an axially symmetric domain of null strings which has a layered structure and radially changes its size has been investigated. It is shown that the action of the gravitational field of such a domain on a test null string for any initial conditions leads to oscillations of a test null string inside a region limited in space. The motion (drift) of the region inside which the test null string oscillates depends on the ratio of the initial parameters characterizing the test null string and the null string domain. These regions can be considered as particles localized in space with an effective nonzero rest mass. For these particles, you can enter the concept of “life time”, which depends on the number of layers in the multi-string system. It is also possible to introduce the concept of particle “mass” (energy), which is determined by the size of the region in which the null string oscillates and depends on the trajectory of the null string in this region. Under the influence of changing external conditions one kind of particles can pass into another.

scholarly journals Finite Rest Masses of Wave Quanta in Material Media

1971 ◽  
Vol 24 (4) ◽  
pp. 871 ◽  
Author(s):  
KD Cole
Keyword(s):  
Gravitational Field ◽  
Doppler Effect ◽  
Plasma Frequency ◽  
Rest Mass ◽  
Gravitational Redshift ◽  
Mass Energy ◽  
Dynamical Equations ◽  
Dispersion Relationship ◽  
New Form ◽  
The Doppler Effect

The equivalence of a dispersion relationship and Einstein's mass--energy relationship leads to the specification of a particle in a vacuurrt which is equivalent to a "photon" in a medium. The invariance of the rest mass of this particle leads to a formula for the Doppler effect which is good for all forms of waves whose quanta can be described by E = nw and p = nk. Applying dynamical equations to the equivalent particle in the case of a radiofrequency photon in a plasma around a star, a new gravitational redshift formula is deduced which reduces to the well-known expression in the appropriate limit. A new form of bending of photon trajectories in a gravitational field is also described. At frequencies near the plasma frequency Vp the bending is vp/4(v-vp} times that for light in a vacuum.

On a non-symmetric theory of the pure gravitational field

1958 ◽  
Vol 54 (1) ◽  
pp. 72-80 ◽  
Author(s):  
D. W. Sciama
Keyword(s):  
Gravitational Field ◽  
Energy Momentum Tensor ◽  
Equations Of Motion ◽  
Rest Mass ◽  
Symmetric Tensor ◽  
Momentum Tensor ◽  
Unified Field Theory ◽  
Field Equations ◽  
Metric Tensor ◽  
Unified Field

ABSTRACTIt is suggested, on heuristic grounds, that the energy-momentum tensor of a material field with non-zero spin and non-zero rest-mass should be non-symmetric. The usual relationship between energy-momentum tensor and gravitational potential then implies that the latter should also be a non-symmetric tensor. This suggestion has nothing to do with unified field theory; it is concerned with the pure gravitational field.A theory of gravitation based on a non-symmetric potential is developed. Field equations are derived, and a study is made of Rosenfeld identities, Bianchi identities, angular momentum and the equations of motion of test particles. These latter equations represent the geodesics of a Riemannian space whose contravariant metric tensor is gij–, in agreement with a result of Lichnerowicz(9) on the bicharacteristics of the Einstein–Schrödinger field equations.

scholarly journals The Total Energy and Momentum Stored in a Particle

2017 ◽  
Vol 9 (2) ◽  
pp. 65
Author(s):  
Eyal Brodet
Keyword(s):  
Total Energy ◽  
Special Relativity ◽  
Decay Time ◽  
Rest Mass ◽  
Minimum Time ◽  
Mass Energy ◽  
Light Velocity ◽  
Extra Energy ◽  
Definition Of ◽  
Energy And Momentum

In this paper we reconsider the conventional expressions given by special relativity to the energy and momentum of a particle. In the current framework, the particle's energy and momentum are computed using the particle's rest mass, M and rest mass time, t_m=h/M c^2  where t_m has the same time unit as conventionally used for the light velocity c. Therefore it is currently assumed that this definition of time describes the total kinetic and mass energy of a particle as given by special relativity. In this paper we will reexamine the above assumption and suggest describing the particle's energy as a function of its own particular decay time and not with respect to its rest mass time unit. Moreover we will argue that this rest mass time unit currently used is in fact the minimum time unit defined for a particle and that the particle may have more energy stored with in it. Experimental ways to search for this extra energy stored in particles such as electrons and photons are presented.

Relativistic Electron-Positron Gamma Ray Laser

1986 ◽  
Vol 41 (8) ◽  
pp. 1005-1008
Author(s):  
F. Winterberg
Keyword(s):  
Relativistic Electron ◽  
Gamma Ray ◽  
Center Of Mass ◽  
Rest Mass ◽  
Mass Energy ◽  
Electron Positron ◽  
Pair Annihilation ◽  
Rapid Formation ◽  
Time Requirements ◽  
Dense State

The prerequisite for an efficient electron-positron gamma ray laser, which is the rapid formation o f a dense electron-positron plasma in a time shorter than the time for pair annihilation, is ideally fulfilled in a relativistic electron-positron superpinch. Because the cross section for annihilation decreases quadratically with the center o f mass energy, the time requirements otherwise imposed, are greatly relaxed. A relativistic electron-positron pinch can collapse under a complete population inversion into a very dense state possessing the form o f a long filament, just as it is required for a gamma ray laser. The gamma ray energies are the total center of mass energies, which can be much larger than the electron-positron rest mass energies.

The Riemann tensor and stress singularities

1972 ◽  
Vol 71 (1) ◽  
pp. 131-134 ◽  
Author(s):  
A. Sackfield
Keyword(s):  
Gravitational Field ◽  
Riemann Tensor ◽  
Axially Symmetric ◽  
Stress Singularities ◽  
Symmetric Gravitational Field ◽  
Algebraic Invariants

AbstractThe algebraic invariants of the Riemann tensor for a static axially symmetric gravitational field are examined. Contrary to common expectation they are shown to be well defined in a region of the field known to be physically singular.

scholarly journals New closed analytical solutions for geometrically thick fluid tori around black holes

2018 ◽  
Vol 614 ◽  
pp. A75 ◽  
Author(s):  
V. Witzany ◽  
P. Jefremov
Keyword(s):  
Black Hole ◽  
Initial Conditions ◽  
Rest Mass ◽  
Decisive Role ◽  
Rotational Instability ◽  
Asymptotic State ◽  
Rotation Curves ◽  
Perfect Fluids ◽  
Order Of Magnitude ◽  
Orbital Periods

Context. When a black hole is accreting well below the Eddington rate, a geometrically thick, radiatively inefficient state of the accretion disk is established. There is a limited number of closed-form physical solutions for geometrically thick (nonselfgravitating) toroidal equilibria of perfect fluids orbiting a spinning black hole, and these are predominantly used as initial conditions for simulations of accretion in the aforementioned mode. However, different initial configurations might lead to different results and thus observational predictions drawn from such simulations. Aims. We aim to expand the known equilibria by a number of closed multiparametric solutions with various possibilities of rotation curves and geometric shapes. Then, we ask whether choosing these as initial conditions influences the onset of accretion and the asymptotic state of the disk. Methods. We have investigated a set of examples from the derived solutions in detail; we analytically estimate the growth of the magneto-rotational instability (MRI) from their rotation curves and evolve the analytically obtained tori using the 2D magneto-hydrodynamical code HARM. Properties of the evolutions are then studied through the mass, energy, and angular-momentum accretion rates. Results. The rotation curve has a decisive role in the numerical onset of accretion in accordance with our analytical MRI estimates: in the first few orbital periods, the average accretion rate is linearly proportional to the initial MRI rate in the toroids. The final state obtained from any initial condition within the studied class after an evolution of ten or more orbital periods is mostly qualitatively identical and the quantitative properties vary within a single order of magnitude. The average values of the energy of the accreted fluid have an irregular dependency on initial data, and in some cases fluid with energies many times its rest mass is systematically accreted.

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