Is the Acceleration of the Universe Expansion accelerating?

In summary, Edward Witten discussed the acceleration of the universe in an interview, stating that in the Lambda-CDM model, as the universe expands, the volume also expands exponentially and all derivatives, including the third derivative, also increase exponentially. This is supported by the Friedmann equations.
  • #1
Swimmingly!
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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.
 
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  • #2
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
 
  • #3
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.
 

1. What is the Acceleration of the Universe Expansion?

The Acceleration of the Universe Expansion, also known as the Cosmic Acceleration, refers to the constant expansion of the universe at an increasing rate. This means that the space between galaxies is expanding, causing them to move away from each other at faster speeds.

2. How do we know that the Universe Expansion is accelerating?

Scientists have gathered evidence from various sources such as observations of distant supernovae, cosmic microwave background radiation, and the large-scale structure of the universe. These studies have consistently shown that the expansion of the universe is accelerating.

3. What is causing the Acceleration of the Universe Expansion?

The cause of the Acceleration of the Universe Expansion is still a topic of ongoing research and debate. Currently, the most widely accepted explanation is the existence of dark energy, a mysterious force that is thought to make up about 70% of the total energy in the universe.

4. Is the Acceleration of the Universe Expansion constant?

No, the rate of acceleration is not constant. As the universe expands, the acceleration also increases. This means that the expansion of the universe will continue to accelerate, but at a faster rate.

5. What are the implications of the Acceleration of the Universe Expansion?

The Acceleration of the Universe Expansion has significant implications for our understanding of the universe. It suggests that the universe will continue to expand at an increasing rate, eventually leading to a "Big Freeze" scenario where all matter and energy in the universe will be too spread out for any significant interactions to occur.

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