All Questions
56
questions
7
votes
3
answers
5k
views
If we consider the spacetime of the universe to be four-dimensional, does the Big Bang lie in its center?
Apologies for the (hopefully now somewhat less) clickbait-y title. Now, of course, I know that the Big Bang did not happen at any point connected to a single point in our current $3$-dimensional ...
- 1,897
0
votes
1
answer
98
views
Does The Big Bang Require An Infinitesimal Point, Or Is Another Shape Possible? [duplicate]
Einstein's Spacetime has four dimensions. If the size of one of these dimensions is zero, then the four-dimensional 'volume' - or whatever the corollary to 3D volume is called in 4D - would be zero.
...
- 103
0
votes
2
answers
47
views
Is this the Format of the Observable Universe?
The way I have it is: the Observable Universe looks as follows. In some ball, all the galaxy clusters exist, then in a bigger concentric ball the dark ages exist (no galaxies), then on the surface of ...
- 61
2
votes
1
answer
171
views
Particle horizon in an empty universe
So in this thread,
Can space expand with unlimited speed?,
the author Pulsar made amazing diagrams of different horizons and paths for a benchmark model that describes our current universe, and gave a ...
- 161
0
votes
2
answers
91
views
What is there at a point the universe hasn't expanded past yet? [duplicate]
(Please don't mark as a duplicate)
If the universe is constantly expanding that means that there is a point the univese hasn't expanded past, with that what would be past that point? This isn't about ...
- 11
33
votes
9
answers
9k
views
Is space really expanding?
In a book called "Einstein, Relativity and Absolute Simultaneity" there was this sentence by Smith:
There is no observational evidence for a space expansion hypothesis. What is observed are ...
user311398
0
votes
0
answers
24
views
What was the volume of the universe a short time after the big bang? [duplicate]
I assume this question is somehow ill posed, but I do not know in which way.
I think it is not a difference here whether the universe expanded into space,
or space expanded itself.
Seen from the ...
- 3,901
1
vote
2
answers
120
views
How many dimensions Big Bang had? [closed]
I just watched "Through the Wormhole S01E04 What Happened Before the Beginning" and a question just popped into my head.
Time dimension should not exist at that moment I think, but I wonder ...
- 137
1
vote
1
answer
336
views
Did the Big Bang cause an outward push of gravity?
There is a theory that the big bang’s blast caused an outward push, a kind of reverse gravity if you will, of our universe and everything within it.
My question is how could this have happened? If it ...
- 179
0
votes
1
answer
134
views
Does it violate energy conservation? (What are the possible flaws in my reasoning?) [closed]
The universe has been expanding since the Big Bang. This expansion of the spacetime fabric can be estimated by the Hubble’s constant, and is usually compared (analogously) to a ballon being blown up, ...
- 178
1
vote
2
answers
1k
views
When did the Big Bang happen?
Did the Big Bang happen at a point? goes through the fact that the Big Bang happened everywhere at the same time. John Rennie's answer explains this as being a consequence of all points in space ...
- 2,162
1
vote
1
answer
139
views
How was matter in other parts of the universe affected by the Big Bang and inflation in an infinitely sized universe?
I'm trying to understand how the idea of an infinite universe with presumably infinite matter works with the Big Bang and inflation.
I understand that if the universe is infinite, then it's always ...
- 199
0
votes
2
answers
92
views
What can we find if we went back to where the big bang happened?
Space after the big bang occurred have expanded dramatically. However at the same time the big bang happened it started to expand from that moment so what can we find before that point. For example, ...
- 13
0
votes
2
answers
85
views
Various scales of infinite
I was reading a great answer by John Rennie earlier (and took a mental note of the question which I must have mislaid). I wanted clarification by comment so I thought I could look it up amongst John's ...
- 58
1
vote
1
answer
112
views
Did the big bang start at ONE infinitely curved point (or a 4D curved ball shrunk to a point) with an infinite density of energy?
I'm confused. In this question it is said:
The simple answer is that no, the Big Bang did not happen at a point. Instead, it happened everywhere in the universe at the same time.
How could it have ...
