A few thoughts on timeline & entropy

[sacscale]

If we agree that universe has a beginning and if we know that the entropy increases over time (a broken window won't fix itself),

I reckon that entropy had to be zero or a constant some point in past. Then if universe is to begin shrinking, that means it's returning to the primal state of higher order and

least entropy - the entropy'd start to decrease- in that case the usual thermodynamic direction of time will reverse - the window pieces will jump together and the window will be whole again.

The psychological direction of time would also reverse: we wouldn't remember past but future - but that also raises paradoxes like "Could we die before we're born?" etc.

These are just some of my thoughts on this subject, I'm 15 and would like to hear your opinion on this.

 

 

Hawkins discussed this in "A Short History of Time" however the evidence indicates that not only does the universe continue to expand but that expansion is accelerating.

[Djordje]

Hawkins discussed this in "A Short History of Time" however the evidence indicates that not only does the universe continue to expand but that expansion is accelerating.

 

Yes, an inflationary model.

[IM Egdall]

Yes, an inflationary model.

 

No, not exactly. The inflationary model says that the universe expanded exponentially just moments after the big bang. It then setted down to a much slower uniform expansion. This uniform expansion is predicted by the theory of general relativity. Then in 1998 examination of supernova data said that this expansion has actually been speeding up for the past 5-7 billion years. No one knows exaclty what is causing this speeding up of the expansion of the universe; so it is called dark energy. In summary:

 

Initlal exponential expansion (over a fraction of a second after big bang) - Inflation theory

 

Subsequent uniform expansion (over billions of years from big bang) - Theory of general relativity

 

Recent increase in the rate of expansion (last 5 - 7 billion years) - Dark energy

Edited March 21, 2011 by I ME

[Djordje]

No, not exactly. The inflationary model says that the universe expanded exponentially just moments after the big bang. It then setted down to a much slower uniform expansion. This uniform expansion is predicted by the theory of general relativity. Then in 1998 examination of supernova data said that this expansion has actually been speeding up for the past 5-7 billion years. No one knows exaclty what is causing this speeding up of the expansion of the universe; so it is called dark energy. In summary:

 

Initlal exponential expansion (over a fraction of a second after big bang) - Inflation theory

 

Subsequent uniform expansion (over billions of years from big bang) - Theory of general relativity

 

Recent increase in the rate of expansion (last 5 - 7 billion years) - Dark energy

 

Thanks for this information. I haven't known that it was that short period during which it expanded exponentially.