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Menikmati
03-November-2003, 11:28 PM
The three arrows of time are the thermodynamic arrow, phychological arrow, and the cosmological arrow. The thermodynamic arrow is where disorder increases with time, the psychological arrow is why we remember the past but not the future, and there is the cosmological arrow is which the universe expands rather then contracts. It is said that the thermodynamic and the psychological arrow of time are connected together in which they both run on the same path. So does the cosmological arrow just run on its own path all by itself or does it have any relation with the thermodynamic and psychological arrow of time? The reason asking is because if you believe in the big crunch then the cosmological arrow must reverse itself for the universe isn't expanding anymore and if the cosmological arrow is related with any of those two then those two must also reverse. Then in the big crunch the dish that you just broke would simpy be back to its fixed state and you would know remeber the future instead of the past. I mean its really not likely for that not to happen but what do you think or know about this subject? Thanks
Matthew
04-November-2003, 05:46 AM
The thermodynamic arrow is where disorder increases with time, the psychological arrow is why we remember the past but not the future, and there is the cosmological arrow is which the universe expands rather then contracts

Who says the universe will not contract? We do not know this for a fact.
Menikmati
04-November-2003, 04:33 PM
Ahh yes that is true , but that it theory is if you believe in the big crunch.
DippyHippy
05-November-2003, 03:12 AM
Why does disorder increase with time? Surely "in the beginning" there was chaos in the universe and now there's (relatively speaking) order`?
Matthew
05-November-2003, 10:38 AM
Its entropy. There was chaos, but all the matter was clumped, over time though it spread out, entropy. Entropy is decreased by gravity, even cancelled out. If there is enough gravity entropy is reversed and we'll have a big crunch.
DippyHippy
06-November-2003, 05:08 AM
I'm not sure what you mean by entropy... could you explain a little more please?
Haglund
07-November-2003, 11:08 PM
My questions:
Is it possible to imagine a creature that remembers the future?
If there are three arrows of time, are there then three futures?
Matthew
07-November-2003, 11:38 PM
Is it possible to imagine a creature that remembers the future?

I don't think so. How can something remember what hasn't happened yet?
Haglund
08-November-2003, 10:40 AM
Originally posted by matthew@Nov 7 2003, 11:38 PM
Is it possible to imagine a creature that remembers the future?

I don't think so. How can something remember what hasn't happened yet?
I was thinking about this just now, I've read that if tachyons do exist, they would go back in time? What does that even mean? That their age is decreasing? If so, then how old were they?

And here is something interesting to read:
http://spot.colorado.edu/~vstenger/Briefs/...TimeTravel.html (http://spot.colorado.edu/~vstenger/Briefs/QuantumTimeTravel.html)