All Questions
Tagged with dark-energy thermodynamics
11
questions
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What causes a big rip?
If dark energy has $w<-1$ you get the Big rip scenario, where dark energy becomes more and more powerful until it eventually rips all matter apart. Why does this occur? Why does having $w<-1$ ...
- 2,908
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Kinetic energy and collisions in cosmology? [duplicate]
Objects in space time can move due to the expansion of spacetime itself (where objects that are sufficiently far apart would recede from each other due to the Hubble flow) and peculiar motions (which ...
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Dark Energy & Thermodynamics
I'm not sure I'm understanding this correctly, but I recently read that the repulsive force of dark energy is responsible for the creation of new space as the universe expands - and since empty space ...
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Why can't work be done by dark energy on cosmic scales?
My rudimentary understanding of dark energy as the cosmological constant is that the vacuum state of space has positive energy but negative/repulsive gravity/pressure.
Given a system dominated by &...
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$\rho-3P$ for ultra-relativistic regime in early universe
I am trying to read this paper, in which they try to get dark energy by modifying the EFEs to its unimodular form. As interesting as it may be for someone here, I'm struggling to understand the ...
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Can the fact that dark energy increases with volume be explained by classical thermodynamics?
Considering adiabatic process in classical thermodynamics, a normal substance with (positive) pressure must do work on its environment in order for the volume to increase by $ dV $(like pushing the ...
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Would it be possible for dark 'energy' to follow the laws of thermodynamics?
Would it be possible for dark 'energy' to follow the laws of thermodynamics? I hope, this is something that can be answered.
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Can dark energy be explained by 2nd law of thermodynamics?
The second law of thermodynamics states that entropy cannot decrease over time. If entropy is simply the description of how "uniformly" spread out energy is over space then doesn't it follow, as a ...
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Why is it important that the equation of state parameter of dark energy is measured?
The equation of state for a perfect fluid is that $p=\omega \rho c^{2}$, where $p$ is the pressure, $\rho$ is the density, $c$ is the vacuum speed of light, and $\omega$ is called the equation of ...
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Less than absolute zero possible? [duplicate]
Possible Duplicate:
Temperature below absolute zero?
According to this article
http://www.sciencemag.org/content/339/6115/52 (preprint: http://arxiv.org/abs/1211.0545)
it is. What do you think....
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How many times brighter could the stars shine without raising the temperature of space?
If my understanding is correct, the temperature of space (as defined by the temperature that a black-body will reach) has been decreasing since the big bang. It has never increased. Additionally, ...
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