Negative Gravity Force Created by Gravitational Collapse of the Star

Shape Dynamics (SD) is a field theory that describes gravity in a different way than General Relativity (GR): it assumes a preferred notion of simultaneity, and the dynamical content of the theory consists of conformal 3- geometries. SD coincides with (GR) in most situations, in particular in the experimentally well-tested regimes, but it departs from it in some strong-gravity situations, for example at cosmological singularities or upon gravitational collapse. This chapter provides a quick introduction to the theory and a brief description of its present state.

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Magnetic field amplification in newly-born neutron stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100042056 ◽

1996 ◽

Vol 160 ◽

pp. 435-436

Author(s):

H.-J. Wiebicke ◽

U. Geppert

Keyword(s):

Magnetic Field ◽

Neutron Stars ◽

Gravitational Collapse ◽

Dipole Field ◽

Numerical Calculations ◽

Selection Effects ◽

Thermoelectric Effects ◽

Field Amplification ◽

Seed Field ◽

Flux Conservation

AbstractWe present a scenario of magnetic field (MF) evolution of newly-born neutron stars (NSs). Numerical calculations show that in the hot phase of young NSs the MF can be amplified by thermoelectric effects, starting from a moderately strong seed-field. Therefore, there is no need to assume a 1012G dipole field immediately after the gravitational collapse of the supernova (SN) event. The widely accepted scenario for such a field to be produced by flux conservation during the collapse is critically discussed. Instead, it can be generated by amplification and selection effects in the first 104yrs, and by the subsequent fast ohmic decay of higher multipole components, when the NS cools down.

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Examining gravitational collapse with test scalar fields

Classical and Quantum Gravity ◽

10.1088/0264-9381/27/16/165019 ◽

2010 ◽

Vol 27 (16) ◽

pp. 165019 ◽

Cited By ~ 4

Author(s):

Ryo Saotome ◽

Ratindranath Akhoury ◽

David Garfinkle

Keyword(s):

Gravitational Collapse ◽

Scalar Fields

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Conformal mapping of the Misner–Sharp mass from gravitational collapse

International Journal of Modern Physics D ◽

10.1142/s0218271816500814 ◽

2016 ◽

Vol 25 (07) ◽

pp. 1650081 ◽

Cited By ~ 9

Author(s):

Fayçal Hammad

Keyword(s):

Conformal Mapping ◽

Gravitational Collapse ◽

Conformal Transformation ◽

Conformal Mappings ◽

Conformal Transformations ◽

Theories Of Gravity ◽

Definition Of ◽

Geometric Definition

The conformal transformation of the Misner–Sharp mass is reexamined. It has recently been found that this mass does not transform like usual masses do under conformal mappings of spacetime. We show that when it comes to conformal transformations, the widely used geometric definition of the Misner–Sharp mass is fundamentally different from the original conception of the latter. Indeed, when working within the full hydrodynamic setup that gave rise to that mass, i.e. the physics of gravitational collapse, the familiar conformal transformation of a usual mass is recovered. The case of scalar–tensor theories of gravity is also examined.

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Experimental study of a closed loop flat plate pulsating heat pipe under a varying gravity force

International Journal of Thermal Sciences ◽

10.1016/j.ijthermalsci.2015.04.010 ◽

2015 ◽

Vol 96 ◽

pp. 23-34 ◽

Cited By ~ 28

Author(s):

V. Ayel ◽

L. Araneo ◽

A. Scalambra ◽

M. Mameli ◽

C. Romestant ◽

...

Keyword(s):

Experimental Study ◽

Flat Plate ◽

Heat Pipe ◽

Closed Loop ◽

Gravity Force ◽

Pulsating Heat Pipe

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Electron capture during gravitational collapse in type II supernov AE

Physics Letters A ◽

10.1016/0375-9601(83)90190-1 ◽

1983 ◽

Vol 96 (6) ◽

pp. 322-326 ◽

Cited By ~ 4

Author(s):

Kamales Kar ◽

Alak Ray

Keyword(s):

Electron Capture ◽

Gravitational Collapse ◽

Type Ii

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Numerical Modeling of the Motion of the Flat Textile Structures

ISRN Mechanical Engineering ◽

10.5402/2011/457462 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8

Author(s):

Piotr Szablewski

Keyword(s):

Numerical Modeling ◽

Boundary Conditions ◽

Discrete Model ◽

Gravity Force ◽

Dynamic Conditions ◽

Textile Structure ◽

Sewing Thread ◽

Lagrange’S Equations ◽

Lagrange's Equations ◽

Time Boundary

In many problems from the field of textile engineering (e.g., fabric folding, motion of the sewing thread) it is necessary to investigate the motion of the objects in dynamic conditions, taking into consideration the influence of the forces of inertia and changing in the time boundary conditions. This paper deals with the model analysis of the motion of the flat textile structure using Lagrange's equations in two variants: without constraints and with constraints. The motion of the objects is under the influence of the gravity force. Lagrange's equations have been used for discrete model of the structure.

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