Time - How Long was the first second?

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If a singularity slows time. How long was the first second after big bang?
 
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The first second, was by definition, one second long.
 
A second by my watch is different from a second next to a singularity. Are you saying it would be the time it took light (if it had existed) to travel 186000 miles (in which case it would have been a really long second)? Just trying to get this concept right in my head before I launch into more study.
 
TonyLondon said:
A second by my watch is different from a second next to a singularity.
No, it is not. It looks different to a remote observer but that's a different story.

Are you saying it would be the time it took light (if it had existed) to travel 186000 miles (in which case it would have been a really long second)? Just trying to get this concept right in my head before I launch into more study.
Yes, It would have been the time it took light to travel 186000 miles along a spacetime geodesic, assuming there was nothing to get in its way.
 
How do you measure that "first second"?

;)Aleksandr Solzhenitsyn: "Who could act rationally on the first morning of Creation?" (Cancer Ward)o_O

Garth
 
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TonyLondon said:
A second by my watch is different from a second next to a singularity.

If you're thinking of a black hole, this applies to an observer "hovering" near the horizon, not the singularity (you can't "hover" near the singularity since you'd be inside the horizon and everything inside the horizon has to fall inward), and, as phinds says, it refers to a second by that observer's clock as seen by a remote observer.

None of this applies to the initial singularity in the Big Bang model. First, that singularity is a past singularity, not a future singularity (like a black hole's); second, you can't "hover" near the Big Bang, since it's really a moment of time, not a place in space (it would be like trying to "hover" near last Tuesday); and third, the concept of "gravitational time dilation" such as occurs near a black hole's horizon is not applicable to the universe as a whole, since it only works in a stationary spacetime and the universe is not stationary.

So the only real answer to your question is Matterwave's: a second is a second by definition.
 
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https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
Hi, I’m pretty new to cosmology and I’m trying to get my head around the Big Bang and the potential infinite extent of the universe as a whole. There’s lots of misleading info out there but this forum and a few others have helped me and I just wanted to check I have the right idea. The Big Bang was the creation of space and time. At this instant t=0 space was infinite in size but the scale factor was zero. I’m picturing it (hopefully correctly) like an excel spreadsheet with infinite...

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