The Big Bang

[Shadowy Man]

A quick google search on the phrase "after the Big Bang" gives results that imply that the "Big Bang" is being used to mean t=0, for better or for worse. Technically speaking, the "Big Bang" isn't an event, it is a description of the model that says the universe was once in a hot, dense state and has been expanding since then.

There was no heat--and no bang--at T=0.

We don't know the state of the universe at t=0. We don't yet have the physics to understand it.

 

[skepticalbip]

There was no heat--and no bang--at T=0.

We don't know the state of the universe at t=0. We don't yet have the physics to understand it.

Even further, we don't know if there was a t=0.

 

[Wiploc]

We don't know the state of the universe at t=0. We don't yet have the physics to understand it.

Even further, we don't know if there was a t=0.

If there was no t=0, then it follows that it's not true that t=0 was hot and dense.

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There was no heat--and no bang--at T=0.

We don't know the state of the universe at t=0. We don't yet have the physics to understand it.

I don't think you can find any physicist who will describe a singularity as hot.

 

[T.G.G. Moogly]

I don't think you can find any physicist who will describe a singularity as hot.

So a singularity possesses no motion?

 

[skepticalbip]

I don't think you can find any physicist who will describe a singularity as hot.

So a singularity possesses no motion?

The term, singularity, doesn't refer to a physical thing. It is simply a term that means that the mathematical model no longer gives meaningful solutions, only infinities.

ETA:
As an example;

An electron's electric field strength at various distances from the electron would be the electron's charge divided by the distance squared. So the field strength increases by the square of the distance as the electron's position is approached. At the point of the electron the equation would have the electric field strength go to infinity since the distance, r, goes to zero. The simple equation obviously no longer gives a meaningful solution - this is a singularity.

 

[Wiploc]

I don't think you can find any physicist who will describe a singularity as hot.

So a singularity possesses no motion?

Everything is stopped relative to itself. If we're no longer talking about time zero, we can say that a singularity has motion relative to other things (which is the same as saying that other things are moving relative to it).

If you are asking whether there is motion within the singularity, that wouldn't make sense.

 

[Shadowy Man]

Even further, we don't know if there was a t=0.

If there was no t=0, then it follows that it's not true that t=0 was hot and dense.

- - - Updated - - -

There was no heat--and no bang--at T=0.

We don't know the state of the universe at t=0. We don't yet have the physics to understand it.

I don't think you can find any physicist who will describe a singularity as hot.

The t=0 density singularity is an extrapolation of a classical model into a regime where we know there must be quantum effects, so it's currently a placeholder for our ignorance.

 

[Wiploc]

If there was no t=0, then it follows that it's not true that t=0 was hot and dense.

- - - Updated - - -

There was no heat--and no bang--at T=0.

We don't know the state of the universe at t=0. We don't yet have the physics to understand it.

I don't think you can find any physicist who will describe a singularity as hot.

The t=0 density singularity is an extrapolation of a classical model into a regime where we know there must be quantum effects, so it's currently a placeholder for our ignorance.

I can't tell whether you're conceding my point.