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Photons (radio waves, "light", gamma-rays, etc.) and neutrinos contribute negligibly to the total energy density of the Universe. By far, most of the photons that exists today are the cosmic microwave background, with 450 photons per cm$^{3}$ (e.g. Hobson et al. 2006). The number density of neutrinos is similar, 330 per cm$^{3}$. In total, the energy density ...

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Here is an experiment trying to limit dark energy theories which predict detectable interactions with matter: If dark energy --- which drives the accelerated expansion of the universe --- consists of a light scalar field, it might be detectable as a "fifth force" between normal-matter objects, in potential conflict with precision tests of gravity. ...

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Nobody knows. There are multiple explanations for dark energy that haven't been eliminated. One of the explanations that hasn't been eliminated is zero point energy: http://arxiv.org/abs/1205.3365. Another possible explanation is that the alleged expansion is actually a result of neglecting the effects of inhomogeneities on averaging: ...

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There is a number of misconceptions in the question. I did not downvote the question, but I will just try to address some of the mistakes. In Quantum Field Theroy (QFT) all fields permeat all space. I am not sure what you mean by "gluon fluctuating field" - there is simply a quantum field for each particle type: not only for gluons, but also for electrons, ...

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