Register to reply 
Inflation as a solution to the Early Universe Enrtopy problem 
Share this thread: 
#1
Dec1412, 07:52 AM

P: 452

I really think this paper
http://arxiv.org/abs/1212.1087 which Chronos mentioned in another thread deserves its own thread. Has anyone had a chance to look at it? what do you think? This has been a lot of noise about this issue raised by people like Roger Penrose and Sean Caroll . They have come up with the some pretty , shall we say, creative ideas such as CCC and the Caroll/Chen model to deal with this issue. But if this paper is right they are not required. 


#2
Dec1512, 10:12 AM

P: 534




#3
Dec1512, 12:48 PM

Sci Advisor
P: 4,802

That said, I don't think you should lump in CCC with the Caroll/Chen model. The Caroll/Chen model is fairly reasonable. The CCC model is way, way, way out there. 


#4
Dec1512, 04:26 PM

Sci Advisor
PF Gold
P: 9,447

Inflation as a solution to the Early Universe Enrtopy problem
They are using von Neumann entropy as a measure of entropy, which is the quantum version of entropy. This appears entirely reasonable to me. The Carroll/Chen model, http://arxiv.org/abs/hepth/0410270, invokes eternal inflation, which has its own issues.



#5
Dec1612, 05:04 AM

P: 452

http://arxiv.org/abs/0912.4093 http://arxiv.org/abs/1011.4249 So it seems to be possible both of these results are valid, if so might a solution then have been found? BTw on the CCC model and Caroll/Chen models, I was simply trying to ascertain if this paper (perhaps combined with the results in the 2 paper I mention above) removes the need for such models. How reasonable or unreasonable they was not my issue here. 


#6
Dec1612, 07:28 AM

P: 534

The whole point of the paper, as I understand it, is that they are trying to explain how inflation can get started entirely within the quantum entanglement framework. 


#7
Dec1612, 12:02 PM

Sci Advisor
P: 4,802




#8
Dec1612, 08:13 PM

P: 534




#9
Dec1712, 02:42 PM

Sci Advisor
P: 4,802




#10
Dec1812, 12:08 AM

P: 534




#11
Dec1812, 05:27 AM

P: 534




#12
Dec1812, 05:58 AM

P: 452

As I understand there are two issues that we would like answers to (well obviously more than 2 but 2 related to this thread):
1 how did inflation get started and how likely was that state? 2 why was the entropy of the early universe so low? From my reading the paper attempts to address question 2 and a paper like Ashtekar/Sloan addresses question 1. So assuming 1 is solved I dont think that means that 2 is solved or am I wrong? 


#13
Dec1812, 08:27 AM

P: 534

To be frank, I am not sure if explaining inflation is sufficient, but one way to think about the issue is as what McInnes mentioned in http://arxiv.org/abs/0711.1656v2.



Register to reply 
Related Discussions  
Inflation of the Universe.  Cosmology  20  
Very very early universe help!  Cosmology  16  
What gave rise to cosmic inflation of the early Universe?  Cosmology  4  
Early Universe  Cosmology  3  
The early universe  Astronomy & Astrophysics  22 