All Questions
352
questions
1
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2
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1k
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If the Big Bang theory suggests that the Universe is "expanding" then what is it expanding INTO? [duplicate]
I am a software engineer and not an astrophysicist but I want to know if anyone is working on sorting out what exists outside the universe?
So what about outside spacetime? what is there? or shall I ...
- 127
15
votes
6
answers
17k
views
What is our location relative to the Big Bang?
Given what we know about space, time and the movement of galaxies, have we or can we determine what our position is in relation to the projected location of the Big Bang? I've read some introductory ...
- 261
18
votes
6
answers
17k
views
Did time exist before the Big Bang and the creation of the universe? [duplicate]
Does time stretch all the way back for infinity or was there a point when time appears to start in the universe?
I remember reading long ago somewhere that according to one theory time began shortly ...
- 384
125
votes
6
answers
11k
views
What is known about the topological structure of spacetime?
General relativity says that spacetime is a Lorentzian 4-manifold $M$ whose metric satisfies Einstein's field equations. I have two questions:
What topological restrictions do Einstein's equations ...
- 1,734
-2
votes
1
answer
184
views
Four-dimensionalism vs energy economy
Four-dimensionalism claims that the universe is basically one huge space-time worm and that everything exists at once (however you want to say that since "internal time" is then just another ...
- 615
23
votes
5
answers
8k
views
Hubble's law and conservation of energy
If all distances are constantly increasing, as Hubble's law say, then lots of potential energies of form ~$\frac{1}{r}$ changes, so how is the total energy of the Universe conserved with Hubble's ...
- 5,220
7
votes
5
answers
1k
views
What if the size of the Universe doubled?
My question has a silly formulation, but I want to know if there is some sensible physical question buried in it:
Suppose an exact copy of our Universe is made, but where spatial distances and sizes ...
- 5,220