Time - How Long was the first second?

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Discussion Overview

The discussion revolves around the concept of time measurement in relation to the first second after the Big Bang, exploring the implications of singularities and time dilation. Participants examine the definitions and perceptions of time in extreme conditions, particularly near singularities and in the context of the universe's early moments.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions how time is perceived near a singularity, suggesting that the first second after the Big Bang may not align with conventional measurements of time.
  • Another participant asserts that the first second is defined as one second long, regardless of context.
  • Some participants discuss the differences in time measurement between a watch and the experience of time near a singularity, with one proposing that it could be related to the distance light would travel in that time.
  • There is a clarification that the concept of gravitational time dilation applies differently to black holes compared to the initial singularity of the Big Bang, emphasizing that the Big Bang represents a moment in time rather than a spatial location.
  • One participant concludes that, despite the complexities, a second remains a second by definition.

Areas of Agreement / Disagreement

Participants express differing views on the nature of time measurement in extreme conditions, with no consensus reached on how to interpret the first second after the Big Bang.

Contextual Notes

Participants highlight limitations in understanding time near singularities, including the distinction between past and future singularities and the applicability of gravitational time dilation in non-stationary spacetimes.

TonyLondon
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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
 
Last edited:
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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