Questions tagged [space-time]
Questions regarding the 4-dimensional background structure of our universe.
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Universe age and cosmological time dilation throughout intergalactic space
Assuming the cosmological principle, universe has the same age and cosmological time dilation throughout intergalactic space. Why can't we use them as an indicator of synchronicity in two extremely ...
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Would a series of gravitational waves from a supernova affect time on a 200 year old clock just as water waves affected clocks on ships in rough seas?
What effect would gravitational waves have on an old - fashioned mechanical clock on Earth with cogs and weights?
user56626
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How is gravity a force if it is the result of space-time warping and bending?
If gravity is just the result of the bending of space-time, how does that make it a force? Isn’t it just an interaction between celestial bodies?
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How is it known that the stars move in the universe because spacetime is expanding and not that the stars expand through empty space? [duplicate]
Quoting one article,
This expansion should not be thought of as stars flying away from each
other in a static spacetime fabric. Instead, the stars are more or
less static relative to a spacetime ...
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Is the gravitational constant really constant over our Universe?
For instance, if objects are travelling at relatively high speed around 'c', is G the same value for them as for us on earth?
I believe a lot of matter is travelling fast away from other matter, so is ...
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What happens at the edge of a finite and "bounded" universe?
So far, we know only about two types of universes: Infinite and finite universes (Unbounded edition).
In an infinite universe, there is no edge. Because well, an infinite space doesn't have an edge. ...
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Does seeing a gravitationally lensed/magnified galaxy imply that they could also see us as well?
Does an observer in that galaxy see our galaxy magnified as well?
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How do we work out the light travel time on a cosmic scale?
I just read this article in the AUSTRALIAN SKY & TELESCOPE magazine, Nov/Dec 2022 Issue 140, on P16, KEEP YOUR DISTANCE: How far away are the objects we see in the universe? And on P23:
"And ...
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What makes space space?
Consider a situation where everything is removed from the Universe. All matter, all radiation, everything.
Only a completely black void would remain. But what is it? What is this empty "space&...
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What is everything wrong with this theory of dark matter?
So I had a hypothesis about why dark matter exists, but seeing as I've just barely begun studying astrophysics its most likely chock full of misconceptions and oversights. Here's a diagram of the ...
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Could vacuum expansion arising from the Big Bang be a consequence of entanglement?
The model assumed here is that the vacuum is a coherent 4-d manifold, embedded in a background of quantum spacetime “foam”, or bulk. It is further assumed the bulk is itself disentangled, possessing ...
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Question about how it's possible for black holes to have gravity and a possible resolution [duplicate]
1. Assumptions
1.a: gravity propagates at c (maximum)
1.b: gravitational fields cause time dilation
1.c: escape velocity at the event horizon is c
1.d: gravity "warps" space-time, but in ...
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Why can't dark energy be considered a 5th fundamental force?
So I have recently been researching for multiple articles about fundamental forces, currently there are just 4 forces:
Gravity
Electromagnetism
Strong nuclear force
Weak nuclear force
So far there ...
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If E.T. alien civilizations exist, won't those exoplanets be almost the age and rate of progress as ours? [closed]
This question is posed also as a mini theory, although I am really asking if someone knows how some parts of our universe would be far-more advanced if "everything" started at the same time (...
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How would the symmetry of time dilation behave if a wormhole sent you near the rest observer?
The scenario I'm envisioning is this:
A spaceship ("the ship") departs from a rest position ("Point A" or "the planet"), and travels at a relativistic speed towards Point ...
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