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Author Topic: What was the temperature of Universe before Big Bang ? (SBC)  (Read 3230 times)

ScientificBoysClub

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What was the temperature of Universe before Big Bang ?

Well I must say if there is no light .. no heat .. so, temperature of Universe must be - ....

could it be below absolute zero ?



 

Offline Vern

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If you use the Big Bang theory as a predicting tool, there was no universe before the big bang. It did not exist. Time and space did not exist.

But that is just the currently accepted Big Bang theory. The original theory proposed by Abbe Georges Lemaitre didn't discuss it as far as I can see.
« Last Edit: 08/04/2009 12:53:30 by Vern »
 

ScientificBoysClub

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If you use the Big Bang theory as a predicting tool, there was no universe before the big bang. It did not exist. Time and space did not exist.

But that is just the currently accepted Big Bang theory. didn't discuss it as far as I can see.
what was Temperature in that no universe ?
 

Offline Don_1

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Nothing???

Zero, nil, nada???

Perhaps a fraction of a degree above absolute zero???

 

Offline dentstudent

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(The following is open to scrutiny by anyone who knows more about this than I do, which is probably anyone still reading this.)

Temperature is a measure of mean energy. Since there was nothing there, there was nothing to have a temperature. The concept of temperature is redundant here, I think.
 

Offline Vern

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what was Temperature in that no universe ?
Well, in a non-existent universe, what non-existent tool would you use to measure it. As Don_1 posted, the best answer is null. Null is not zero. It is simply a place holder with the capacity to hold a number.
 

Offline LeeE

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(The following is open to scrutiny by anyone who knows more about this than I do, which is probably anyone still reading this.)

Temperature is a measure of mean energy. Since there was nothing there, there was nothing to have a temperature. The concept of temperature is redundant here, I think.

I think you're right.  Rather than temperature, people tend to talk in terms of energy density i.e. the amount of energy per unit volume.  If you treat the BB as starting from a geometric point then the energy density would have been infinite at that stage, even for a finite amount of energy.  However, and while still assuming a finite total quantity of energy in the universe, once the universe acquired size the energy density would have become finite.

As the universe continued to expand the energy density kept dropping, eventually reaching the point where matter could exist and it was only really at that point that temperature could mean anything.
 

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