All Questions
Tagged with faster-than-light universe
48
questions
1
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2
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470
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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
3
votes
1
answer
334
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Can we observe the universe expanding faster than light?
I am looking at the sky, and I see two objects moving away from each other with speed greater than the speed of light.
Light from one object is not fast enough to reach the other. So I decided to help ...
- 2,127
1
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2
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215
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Why is it assumed that special relativity does not apply to a universe expanding faster than light?
An argument I hear repeatedly is the light-speed limit only applies where spacetime is flat, so faster-than-light speed is possible where spacetime is curved. Thus special relativity does not apply ...
- 93
3
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2
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273
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How can spacetime be expanding faster than the speed of light? [duplicate]
How can spacetime be expanding faster than the speed of light when the speed of light is the speed limit of the universe?
- 117
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0
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68
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What would happen if universe wouldn’t accelerate faster than speed of light? [closed]
Its quite stunning to assume that not only space-time is expanding but also the rate of expansion is greather that speed of light.
But after the initial surprise, I ve been wondering if that fenomena ...
- 21
0
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1
answer
52
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Can we think of relativity as a measure to determine the finiteness of universe? [closed]
Let’s consider a hypothetical situation wherein an observer is in the standpoint of a light ray. The observer faces infinite time dilation. Thus time stops for the observer and it'd have transversed ...
- 29
6
votes
1
answer
448
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Why are the most distant galaxies "only" around 13 billion light years away?
According to Wikipedia's List of the most distant astronomical objects, the most distant galaxy (GN-z11) is estimated to be around 13.39 billion light years away from earth.
However, the observable ...
- 3,778
1
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0
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46
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Calculate distance of galaxy 13 billion years ago [duplicate]
How can I calculate the distance of a point from Earth now vs 13 billion years ago? The excerpt below claims it is 8 times further now. Can someone provide relevant equations ?
- 11
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34
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Can the expansion of the Universe be faster than the speed of light? [duplicate]
I am reading the textbook "The Cosmic Perspective 8th ed.", in the chapter describing the earliest moments of the Big Bang, one of the sentences is
[...] a sudden and dramatic expansion of the ...
- 111
3
votes
1
answer
95
views
Is it possible that the universe is not expanding faster than the speed of light? [closed]
What if the speed of light increases proportionately to the expansion of space? Is it possible that light traveling in the medium of space gets to travel faster if the medium is expanding? An analogy ...
- 31
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2
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73
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Speed of at expansion at the start of the big bang [duplicate]
If I understand the basics of the big bang correctly it starts with a very small dense point. At the moment of the big bang, less then microseconds after, the universe is already the size of our solar ...
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27
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How Can the Universe Be Bigger Than It is Old? [duplicate]
My question is this: If we can look back to roughly 500m years after the big bang and have estimated the age of the universe at 13.7B years, why is the galaxy we are looking at not a part of the non-...
- 2,706
0
votes
3
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458
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Travelling at lights speed of light as universe expanding
I have read that the object, the light of which is reached us in 13.8 billion years is actually about 46 billion light years away from us now, due to the expanding Universe.
Lets assume that we ...
0
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0
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33
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How can the universe expand faster than the speed of light? [duplicate]
In Neil deGrasse Tyson's Astrophysics for People in a Hurry, he writes:
By now, one second of time has passed.
*
The universe has grown to a few light-years across...
If nothing can move faster than ...
- 168
2
votes
2
answers
177
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Does our Galaxy move at the speed of light? [closed]
I am not a physicist, but I have a few questions that bother me for a while:
As we do not know if the Universe is infinite or not I assume we do not know our whereabouts in it;
We know,though, there ...
- 611