Questions tagged [dark-energy]
Dark energy is the unknown form of energy that drives the acceleration of the universe's expansion.
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Are modified theories of gravity credible?
I'm a statistician with a little training in physics and would just like to know the general consensus on a few things.
I'm reading a book by John Moffat which basically tries to state how GR makes ...
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Does time expand with space? (or contract)
Einstein's big revelation was that time and space are inseparable components of the same fabric. Physical observation tells us that distant galaxies are moving away from us at an accelerated rate, and ...
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How did the universe shift from "dark matter dominated" to "dark energy dominated"?
In order to get dark energy to dominate, wouldn't you first need another form of energy to push the expansion until dark energy could dominate? Otherwise I don't understand how the universe could ...
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How is dark energy consistent with conservation of mass and energy?
I initially thought that dark energy must in some way violate conservation of mass and energy since the component of the energy density of space that comes from dark energy is constant, and space is ...
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Dark matter and dark energy references
I've been looking for questions about dark matter, and I've read some very interesting answers. However, I desire too look into it deeply.
This is not actually a question. I'm asking the community ...
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Why does dark energy produce positive space-time curvature?
My understanding is that dark energy, or equivalently a positive cosmological constant, is accelerating the expansion of the universe and I have read that this gives empty space-time positive ...
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Theory that gets rid of dark matter/energy
Is there any physics theory that either groups together gravity and dark energy/dark matter or eliminates dark energy/dark matter by modifying standard understanding of gravity or any force? If so, is ...
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Are there experiments taking place right now that might show evidence for or falsify dark energy or dark matter?
What experiments at quantum or cosmic level might provide the strongest supporting evidence for or, conversely, potential for falsifying, the existence of dark matter or dark energy?
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Possibility of making dark energy equivalent with dark matter
I was curious whether it is possible to make dark energy equivalent to dark matter.
Can this unification be done?
If it can, why do scientists prefer to separate dark energy from dark matter?
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What are the alternative theories of dark energy? ($w \neq -1$)
There has been a lot of related questions about dark energy around here but these are usually 2-4 years old and the closest question to mine hasn't really been answered, so I am going to proceed. ...
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How do people calculate proportions of dark matter, dark energy and baryonic matter of the universe?
The Wikipedia page on dark matter mentions that the Planck mission had revealed that in our universe ordinary baryonic matter, dark matter and dark energy are present in the ratio: 4.9%, 26.8% and 68....
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Dark Energy saving the world
Ok, my understanding of physics is still limited, hoping to change that in the following years, but I have a question.
Dark energy is what provokes the expansion of the universe, so, in theory, it ...
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Dark matter and dark energy [duplicate]
Possible Duplicate:
Dark matter references
I have recently read about dark matter and dark energy, and why physicists think it must exist (dark matter: mass of galaxies are far bigger than ...
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Dark Energy / Accelerating universe: naive question
Folks, I have a naive question regarding the subject of dark energy and an accelerating universe:
From what I understand/read, it seems that the further we look out into deep space, the faster the ...
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What is the evidence that dark energy exists? (as of 2020)
Astrophysicists believe that dark energy exists and makes up ~70% of the universe's energy content. What is the evidence that dark energy exists? Wikipedia gives five lines of evidence:
Supernovae. A ...
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