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pi.rootpi
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Well, the title says the most, but the question is: If Virtual particles exist... Could it be dark energy?, if it really can, would it be the same idea of a Cosmological Constant??Thanks!
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pi.rootpi said:Well, the title says the most, but the question is: If Virtual particles exist... Could it be dark energy?, if it really can, would it be the same idea of a Cosmological Constant??
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marcus said:And when the particle physicists calculate what the Vacuum Energy should be according to QFT, they get a figure which is many many powers of ten bigger than that.
out.
pi.rootpi said:Does it mean we don't really know how to calculate it (obvius), but what I mean is that if as long as we keep observing we we'll reach an answer.
I've also heard that cosmologists are trying to find the state equation and i think a professor told me it could be someghing like [tex]-p[/tex] if we accorded light speed was 1 or something like that but I don't really remember, sorry.
Could somebody explain this please?
Thanks!
marcus said:Well the Friedmann-equation that governs a"(t) is a short simple formula involving both the energy density and the pressure--of the matter/energy---basically all the stuff--in the universe.
T.
pi.rootpi said:1. Always we talk about [tex]a(t)[/tex] we're talking about the scale factor, or sometimes it means acceleration?
2. When we derivate this term, what is what we have? I mean, if you derivate space you get velocity, and if you do it twice acceleration, so which is the meaning of derivating [tex]a(t)[/tex]?
3. Another problem I have, is that I'm not english speaker, so there are some terms I don't understand nor to translate (and there is no article in wikipedia in Spanish), so when they talk of Comoving Distances, what do they refer to?
Dark energy is a hypothetical form of energy that is thought to make up about 70% of the total energy in the observable universe. It is believed to be responsible for the observed accelerated expansion of the universe.
Dark energy is closely related to the concept of vacuum energy, which is the energy that exists in empty space. Some theories suggest that dark energy is a manifestation of vacuum energy, while others propose that it is a completely separate entity.
The uncertainty principle, also known as Heisenberg's uncertainty principle, is a fundamental principle in quantum mechanics that states that it is impossible to know both the exact position and momentum of a particle at the same time. This means that there will always be some uncertainty in our measurements of these properties.
The uncertainty principle is relevant to dark energy because it is thought to be a manifestation of quantum fluctuations in the vacuum. These fluctuations create a state of uncertainty in the amount of energy in a given space, which could contribute to the overall energy of the universe.
Dark energy is being studied through various methods, including observations of the cosmic microwave background radiation, the large-scale distribution of galaxies, and the distances and velocities of supernovae. Scientists are also conducting experiments to search for new particles and forces that could help explain the nature of dark energy.