Questions tagged [spacetime]
Within relativity (both special and general), changes of reference frames can change both the notions of space and of time, with one depending on the other as well. As a consequence, it is necessary to treat both concepts in a unified manner. Hence the term spacetime.
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Does Mass Actually Displace Space-Time, or does Mass only Distort it?
1. Question
Given the plethora of space-time illustrations, there is a sense that space-time is actually being displaced by mass, (planets). But on its face, this doesn't really make sense because ...
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Could Space-Time Displace or Distort Itself? [closed]
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Could space-time distort and displace space-time?
If space-time can interact with surrounding space-time, then which ...
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is $LT$ a Lorentz invariant?
We know the relations of time dilation and length contraction
$$L=\frac{L_0}\gamma\\
T=\gamma T_0$$
If we multiply them together, we get
$$LT=L_0T_0.$$
This holds for all $L$ and $T.$
So, is $LT=L'T'$ ...
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On time arrow and coordinate change in General relativity
This may be a silly question but I would like to have things cleared up once and for all in my head.
I will take the example of a Schwarzschild black hole as a solution to vacuum Einstein Field ...
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As I read an article on this website that light cannot warp space time fabric [closed]
But actually we know that energy is equals to mass then light energy can act like mass and it can create a black hole made up of light .
As per Einstein equation E=mc² then why there is no black hole ...
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End points of event horizon
I am reading The Nature of Space and Time by S. W. Hawking. In the last paragraph on page 16 he said that:
event horizon may have past end points but don't have any future end points
I understand ...
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Boundary conditions on transition maps on general relativity
On the initial courses of topology and differential geometry, we learn again and again about charts, and atlas, and transition maps. I feel that transition maps are a very powerful idea, because they ...
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On definition of time in non-inertial frames [closed]
Strictly speaking we can only compare times and lengths in inertial frames of reference because the measuring tools are in the same conditions and aren't subject to G-force. So they are identical ...
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Question on special relativity
I am trying to learn special relativity. If we consider two inertial reference frames with spacetime co-ordinates $(t,x,y,z)$ and $(t',x',y',z')$ and let there be 2 observers who measure the speed of ...
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Looking for papers that claim that spacetime is emergent
This article states:
It’s really striking that for most of the plausible theories of quantum gravity that we have, in some sense their message is, yeah, general relativistic spacetime isn’t in there ...
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Question on spatiotemporal dimensionality about the contradictions of time being a dimension
We can axiomatically see that all spatial dimensions have a fundamental rule where they can either move back or forwards infinitely. However, the temporal dimension started when the universe began and ...
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Under what circumstances can a 4D singularity occur in General Relativity?
I've tried to find on the literature about 4D (single point) singularities, but most of the theorems about singularities pertain to either space-like or time-like singularities, which always have some ...
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What happens if we differentiate spacetime with respect to time? [closed]
Essentially, what would differentiating space-time with respect to time provide us with? What are the constraints associated with such operations? Is it possible to obtain a useful physical quantity ...
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Does gravity accelerate you towards the geodesic of light between you and the mass?
If there's a planet far away, you will accelerate straight towards it due to gravity. If you place a Schwarzschild black hole right in the middle between you and the planet (the distance between the ...
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Do satellites in orbit create Relativity paradoxes? [closed]
Can someone point out the flaw in this very realistic scenario below?
I will start by stating established first principles of the applicable orbital and relativistic conditions.
Then I will describe ...
