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Dr Aaron
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With NASA defining this equilibrium density at 9.9 x 10<30 gm/cm3, how can an increasingly expanding universe maintain a steady density as it expands?
"Dark Energy" is an unknown something that causes the expansion of the universe to accelerate. It makes up something like 70% of everything in the stress energy tensor, and for unknown reasons, it maintains a constant density as the universe expands.Dr Aaron said:With NASA defining this equilibrium density at 9.9 x 10<30 gm/cm3, how can an increasingly expanding universe maintain a steady density as it expands?
Yes, the fact that dark energy maintains a constant density as the universe expands does seem weird. If you can find an explanation for it, I guarantee you a Nobel Prize in physics.Dr Aaron said:Doesn't that suggest that new dark energy is being generated within the universe for there to be an increasing rate of expansion? Then the density could not remain constant without new material to equilibrate the expanding volume. A fixed amount of "stuff" should drop in density when volume expands, yet this seems to contradict pretty basic scientific laws.
Dark matter and dark energy have NOTHING to do with each other and the unfortunate use of the similar names has cause more wasted keystrokes here on PF that any other single topic. There is no increase in DM to correspond to the increasing amount of DE.Dr Aaron said:If it is happening there must be an explanation. The increasing dark energy that expands the universe should be countered by the dark matter noted by findings such as galactic rotational curves, as described by Vera Rubin. I have heard discussions about this, but while we can identify increased dark matter by the expansion of space-time, as we try to identify the entities of dark matter we are having such difficulties in finding dark matter that the only way to measure dark matter is through functions such as evaluation of Einstein-Chowlson rings. Are these findings precise enough to recognize a similar increase for dark matter as we see with dark energy?
I agree, and again, if you can find it, I guarantee you a Nobel Prize.Dr Aaron said:If it is happening there must be an explanation.
The universal equilibrium density problem refers to the question of why the universe has a near-uniform distribution of matter and energy on a large scale.
The universal equilibrium density problem is significant because it is a fundamental question in cosmology that helps us understand the structure and evolution of the universe.
There are several theories that attempt to explain the universal equilibrium density problem, including inflationary theory, dark energy, and the anthropic principle.
Scientists use various methods such as observations of cosmic microwave background radiation, galaxy surveys, and computer simulations to study and gather evidence for the universal equilibrium density problem.
No, there is currently no definitive answer to the universal equilibrium density problem. It is an ongoing area of research and there are still many unanswered questions and debates surrounding it.