All Questions
Tagged with big-bang-theory expansion
18
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Is the expansion of the universe proof of the big bang?
Is the expansion of the universe proof of the Big Bang theory?
Or are there other proofs?
- 4,800
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Why is the Cosmic Microwave Background evidence of a hotter, denser early Universe?
In his book Gravitation and cosmology, Steven Weinberg says that CMB makes it "difficult to doubt that the universe has evolved from a hotter, denser early stage".
In my understanding, the ...
- 1,002
2
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2
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241
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Expansion rate of an infinite universe at the Big Bang
If the universe is infinitely large, then any two arbitrarily distant points must have been arbitrarily close together at some earlier point in time. Doesn't that mean that the expansion rate of the ...
- 2,264
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1
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Strange plot in Max Tegmark book, Our Mathematical Universe
In Max Tegmark's book, Our Mathematical Universe, we can find (in chapter 5, figure 5.3) the following (horrible and poor quality) plot that is supposed to highlight the extreme sensitivity of the ...
- 15k
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What is the explanation for rapid inflation just after the big bang?
I often hear about cosmic inflation occurring rapidly after the Big Bang, but have never came across any explanation for it. What supposedly caused this inflationary period in the early universe? Also,...
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1
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Because the Universe is expanding, what is it taking up?
It is my understanding that the universe is expanding and that matter takes up space. While the universe only contains small percent of matter, wouldn't expansion indicate that the universe is ...
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How can something infinitely big have expanded from an infinitely small?
Please help me reconcile what I see as contradicting theories:
The universe began with the Big Bang and expanded from an infinitesimally small point.
The universe is infinite.
How can something ...
CommunityBot
- 1
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Expansion of space - how do we end up with an unobservable region?
I've just been answering a question on this issue,in physics SE,and realised that my answer conceals a point I don't myself understand.
I understand that
The expansion of metric isn't affected by ...
- 1,030
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Is it fruitful to search for a correlation between rates of in-falling matter in black holes and the expansion rate of our universe? [duplicate]
To my understanding, white holes are hypothetical objects that are time-reversed black holes; black holes gravitationally "suck in" matter whereas white holes "spit" matter back out. As such, I think ...
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How can the universe be expanding faster than speed of light? [duplicate]
So the story goes like this:
A long time ago, 13.799±0.021 billion years to be exact, something happened. It was a big bang, loud explosion and universe came to existence. It grew and grew, and now ...
- 701
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1
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Why is the CMB not simply travelling parallel to us? [closed]
When we look to the distant farthest reaches of the universe we see light that was emitted at the big bang 14 billion years ago. But the universe was tiny back then so that light, which is only ...
- 38.9k
2
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2
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How do we know the universe's expansion is speeding up?
Please forgive my ignorance, I am not an astronomer, just an interested layman.
The further away a galaxy is from us, the faster it is moving away from us. But the galaxies we see exist in the ...
- 126k
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3
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Is it just the observable universe that is expanding?
Is it possible that it is just our observable part of the universe that is expanding, in the time that we exist, and other parts are both expanding and contracting at different rates and times?
Would ...
- 266
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1
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Isn't the date of the Big Bang a bit bogus?
If I understand correctly, the date of the Big Bang is an extrapolation of acceleration of the universe's expansion through time based on the erroneous assumption that the universe is approximately 13 ...
CommunityBot
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2
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Was the Universe expanding before the beginning of inflation?
My point of view is that first there was the Big Bang singularity, and then the period of inflation which resulted in the observable Universe becoming many times bigger. But was the Universe expanding ...
CommunityBot
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