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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Is it possible that humans have the capability to interact with Dark matter? [closed]
Recently, scientists and physicists have been making breakthroughs in dark matter detection. I'm wondering if it's possible for humans to potentially be able to travel deep enough into space to be ...
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By what experiment is the vacuum energy density actually measured?
I have heard that the actual vacuum energy density which is up to 120 orders smaller than the predicted QED value can be measured in experiments or cosmological observations?
What are these ...
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+ spin Photons inside a right hand circularly polarized field with -spin photons outside of that field…”dark matter/energy��
As I understand it, If I am inside of a rh, circularly polarized EM field, there are only +spin photons inside the field: no -spin photons are admitted inside. The field inside serves to “filter” out -...
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Cosmological constant from the stress energy tensor or geometry?
Sabine does make some interesting points. Can a cosmological constant come from the stress energy tensor? If so, I don't see how one is suppose to distinguish this as an all permeating field in the ...
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Inflation, dark energy and symmetry breaking
Aside as the inflaton has been hypothesized to have arisen from the breaking of the $SU(5)$ GUT symmetry, could dark energy have arisen as a weaker inflaton from electroweak symmetry breaking?
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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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Does dark energy cause the creation of spacetime?
The universe is expanding, in theory because of 'dark energy'. Does this mean that this dark energy is causing an increase in the amount of spacetime? I.e., does dark energy cause the creation of ...
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Blueshift caused by dark energy?
Galaxies that are sufficiently far away from our point of view are receding from us due to the accelerated expansion of the universe (supposedly caused by dark energy) and therefore their light is ...
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The slowing of expansion in the matter dominated era
On all the graphs of the inflation of the universe, the era dominated by matter is slowing the rate of expansion. With an intuitive explanation (for all you science communicators out there) could you ...
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What is the estimated velocity of expansion at the beginning of the Dark Energy era?
Approximately 7.5 billion year ago Dark energy began to accelerate the expansion of the universe. Data has shown us that up until that time the universe was decelerating in its expansion velocity. ...
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$\Lambda$CDM's observations and the universe's matter content
It's known that the current value of the universe's total density parameter $\Omega_0=1$.
According to the $\Lambda$CDM model, the current density parameter of baryonic matter $\Omega_P \sim 0.04$, ...
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Flat collapsing universe with dark energy (solution to Friedmann equation)
We always say due to the negative pressure of dark energy, the acceleration equation shows that dark energy will cause positive acceleration $\ddot a >0$.
For a flat universe with cosmological ...
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Dark energy and neutrinos
Neutrinos are sometimes considered to contribute to dark matter, see e.g. E.Siegel.
Why not for dark energy?
There is a similar scale in energy density involved. If you use the current upper limit for ...
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Could dark energy and dark matter be the elusive luminiferous aether that was being searched for over 100 years ago
Is it suggested that dark energy and dark matter is the luminiferous aether that Sir Isaac Newton was proposing might exist?
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Am I wrong if I interpret dark matter just as a red herring to justify the shortcomings of the current theories? [duplicate]
Wikipedia defines
Dark matter is a hypothetical form of matter thought to account for approximately 85% of the matter in the universe.
And continues with
Various astrophysical observations – ...
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