If the big crunch occurred, would time go backwards?

  • Thread starter Dremmer
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In summary, the conversation discusses the possibility of a "big crunch" where the universe begins to shrink and how this could potentially reverse the arrow of time. However, it is stated that the thermodynamic and psychological arrows of time would not necessarily reverse in this scenario. The concept of entropy is also brought up as a factor in the direction of time.
  • #1
Dremmer
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Causing people to start walking backwards, uneating, undrinking, undoing everything they've ever done.
 
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  • #2
Yes, absolutely.
 
  • #3
How would we know? Our future would become our past, and our past would become unpredictable.
 
  • #4
Chronos said:
How would we know? Our future would become our past, and our past would become unpredictable.

i fail to see what you mean.. if the big crunch were a possibility then why would the process leading to it affect the way we perceive time? events would not roll backwards.. (i thought the first reply to dremmer's question was sarcastic, but i doubt your's is, so i had to ask..)
 
  • #5
look up entropy
 
  • #6
granpa said:
look up entropy

ok.. i understand that the concept of big crunch comes along with a certain flip of entropy in order to be valid and thus reversing its overall state from a thermodynamic point of view.. but that doesn't change the fact that time, as we perceive it, remains the same.. (we will still continue to struggle with the invariability of our own past and the annoyance of an unwanted future..)
 
  • #7
No, there is no reason for the thermodynamic or psychological arrows of time to reverse. The thermodynamic arrow of time comes from the fact that we had (for unknown reasons) a big bang with much less than maximal entropy.
 
  • #8
ima not sure, but doesn't entropy always increase, causing time to move in a forward way
if the universe began to decrease in size, that doesn't mean entropy does, so time stays forward :D
 
  • #9
It depends on the physics of a shrinking universe. If entropy increases in an expanding universe, then it could be decreasing in a shrinking one. If entropy decreases, then things would tend to clump up instead of falling apart. Gravity would go up, which could bend space-time.
 

Related to If the big crunch occurred, would time go backwards?

1. What is the Big Crunch?

The Big Crunch is a theoretical concept in astrophysics that suggests the universe will eventually collapse in on itself due to the force of gravity. This would result in all matter and energy being compressed into a singularity, similar to the Big Bang theory of the universe's origin.

2. How would the Big Crunch affect time?

If the Big Crunch were to occur, time would essentially stop as we know it. As the universe becomes infinitely dense, time and space would cease to exist, making it impossible for time to move forward or for anything to happen. This means that time would not go backwards, but rather cease to exist altogether.

3. Is the Big Crunch a likely scenario?

At this point, the Big Crunch is not considered a likely scenario for the fate of the universe. Current research and observations suggest that the universe is expanding at an accelerating rate, making a collapse in on itself less likely. However, it is still a possibility that is being explored by scientists.

4. Would humans be able to survive the Big Crunch?

It is highly unlikely that humans, or any form of life, would be able to survive the Big Crunch. As the universe collapses, all matter and energy will be compressed into an infinitely dense singularity, making it impossible for anything to exist. Therefore, the concept of survival would not apply.

5. What would happen after the Big Crunch?

After the Big Crunch, the universe would essentially start over again with another Big Bang. This cycle of expansion and collapse is known as the "Big Bounce" theory. However, it is important to note that this theory is still highly speculative and requires further research and evidence to be fully accepted by the scientific community.

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