Is the Acceleration of the Universe Expansion accelerating?

Click For Summary
SUMMARY

The discussion centers on the acceleration of the universe's expansion as described by the Lambda-CDM model. Edward Witten's assertion that the acceleration of the universe is itself accelerating is confirmed, as the volume of the universe, represented by V, expands exponentially when dominated by the cosmological constant. This exponential growth implies that not only the first and second derivatives but also the third and higher derivatives of volume are increasing. The Friedmann equations provide the mathematical foundation for this understanding.

PREREQUISITES
  • Understanding of General Relativity (GR)
  • Familiarity with the Lambda-CDM model
  • Knowledge of exponential functions and their derivatives
  • Basic grasp of cosmological constants
NEXT STEPS
  • Study the Friedmann equations in detail
  • Explore the implications of the cosmological constant on universe expansion
  • Learn about the mathematical properties of exponential functions
  • Investigate the observational evidence supporting the Lambda-CDM model
USEFUL FOR

Astronomers, physicists, cosmologists, and anyone interested in the dynamics of universe expansion and the implications of the Lambda-CDM model.

Swimmingly!
Messages
43
Reaction score
0
I watched an interview with Edward Witten some time ago and something he said surprised me.
(http://www.youtube.com/watch?v=eEutI_JKr7A) 3:25
"Which in GR causes the acceleration of the universe to accelerate."
Did he literally meant this?
I'm not sure how accurately you can talk about the volume of the universe, but am I interpreting what he said right?
Is
gif.latex?\frac{d^{3}V}{dt^{3}}%3E1.gif
true?
I'm aware it is true for the second derivative but for the third too?

V=Volume

I hope this is in the right section. Thanks.
 
Last edited:
Space news on Phys.org
If the Lambda-CDM model is correct, the universe will become more and more dominated by the cosmological constant as it expands. When it is lambda-dominated, it expands exponentially, so the scale factor goes like a~exp(K t). Since the volume V ~ a^3, the volume is also expanding exponentially. For an exponential function, all derivatives are increasing exponentially. So the answer to your question is yes, the third derivatives and all higher derivatives are increasing as well. See:

http://en.wikipedia.org/wiki/Friedmann_equations
 
phyzguy said:
If the Lambda-CDM model is correct, the universe will become more and more dominated by the cosmological constant as it expands. When it is lambda-dominated, it expands exponentially, so the scale factor goes like a~exp(K t). Since the volume V ~ a^3, the volume is also expanding exponentially. For an exponential function, all derivatives are increasing exponentially. So the answer to your question is yes, the third derivatives and all higher derivatives are increasing as well. See:

http://en.wikipedia.org/wiki/Friedmann_equations

That answers it. Thank you.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 44 ·
2
Replies
44
Views
14K
  • · Replies 23 ·
Replies
23
Views
3K
  • · Replies 4 ·
Replies
4
Views
5K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 7 ·
Replies
7
Views
2K