All Questions
Tagged with big-bang space-expansion
321
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When was the Higg's particle created after the Big Bang?
Was the Higg's particle created with the Bag Bang?
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Can we infer the size of the whole universe from its expansion rate? [closed]
If the universe inflated to 100 billion km in its first second, that suggests only 1/160,000 of it was observable from any point at that moment. The expansion rate slowed after that, of course, but ...
- 384
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Why is cosmological time unique?
According to the definition I have encountered for the concept of cosmological time, it is defined in the following way:
The cosmological principle states that, at each location in the universe, it ...
- 293
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Has it been proven the fine-structure constant (FSC) changes with time?
I have heard this claimed over and over, even that the FSC was 1 at the Big Bang. Is there any actual consensus among scientists that this is so?
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Isn't the universe older than 13.8 billion years? [duplicate]
To preface this, I'm not an expert, I'm just an avid astronomer with little mathematical knowledge.
I was watching a video that was explaining the cosmic scale and how the observable universe is only ...
- 299
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Time dilation between now vs right after the Big Bang should imply the universe is much older than 13.8 bn years? [duplicate]
The universe is said to be 13.8 bn years old. But if we go back in time towards the Big Bang singularity time will slow down more and more and eventually stop because of the density of the singularity....
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Size of the universe 13 billion years ago
When wee look at the sky in opposite directions, we can see early galaxies that were formed about 13 billion years ago. At that time, the distance between two such galaxies at the opposite ends of the ...
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Could an observer in time determine whether time had no beginning or had a beginning infinitely long ago? [closed]
I don't know if this is more a question for mathematicians or physicists (or even philosophers), but what would be the difference between time having a beginning infinitely long ago and time having no ...
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"What" was expanding during the Inflationary epoch?
I know, space. But in my opinoin, space makes only sense if there is something that experience things like position and distance. A universe without anything that require position and distance to ...
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Why do we need inflation?
wiki (https://en.wikipedia.org/wiki/Inflation_(cosmology)) says that immediately after BB there was expansion at speed greater than $c$, what makes this necessary, what would happen if expansion took ...
user337596
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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
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Cosmos at minimum 250x bigger than our observable Universe, so why then the need for a Big Bang?
Please correct me If I'm wrong but does not the BB only refers to our light speed limited observable Universe (OU) from our home position?
Also it is estimated that the Cosmos is minimum 250 times the ...
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Is a meter constantly getting bigger? [duplicate]
If the bigbang is the start of the expansion of space everywhere then does that mean that a 1 meter ruler is bigger tomorrow than it was today?
Does this apply to the size of atomic particles and ...
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88
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How could proper distance today be infinity in a curvature only Universe when the age is finite?
So for a curvature only universe, the Friedmann equation becomes
and we get the solution $a(t) = t/to$, and $to = 1/Ho$.
If we calculate the proper distance today we will get
As $z-> infinity$, ...
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Confused about size of the universe in the past
From Wikipedia, I got that the photons of the cosmic microwave background radiation originated when the spherical volume of space which will become the observable universe was 42 million light-years ...
user338734