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The Higgs field has a nonzero vacuum expectation value which contributes to the energy density of the Universe. Energies contribute to the curvature of spacetime and affected by gravitational potential wells. Therefore, I have the following questions:

Why can't the Higgs vacuum energy clump to galaxies (the gravitational potential wells created by the galactic mass distribution) like dark matter do? Why isn't it more likely to found around the galaxies?

In other words, why can't the Higgs condensate be a candidate of dark matter(instead of a component of dark energy)?

Note Please understand that it is not a duplicate of my previous question here which is related to Higgs boson, not the Higgs condensate density $v$, an energy density in space that can couple to gravity.

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closed as unclear what you're asking by AccidentalFourierTransform, ACuriousMind Jun 13 '18 at 17:26

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The Higgs condensate should act like a vacuum energy i.e. a form of dark energy. If it gravitated it would would produce a dark energy around 50 orders of magnitude larger than the observed dark energy and the universe would have experienced a sufficiently rapid accelerating expansion that no macroscopic structures would ever have formed.

This is because the Higgs condensate is a fundamental property of space i.e. its energy density remains constant as space expands instead of diluting as space expands. This results in it producing a negative pressure which drives the expansion. By contrast normal and dark matter dilute as space expands and are normally considered pressureless.

Explaining this away is something of an embarrassment. Generally we assume that the Higgs condensate does not contribute to the stress-energy tensor for reasons that are unknown.

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  • $\begingroup$ How does it differ from dark matter? @JohnRennie $\endgroup$ – SRS Jun 13 '18 at 16:49
  • $\begingroup$ @SRS I've extended my answer to address this $\endgroup$ – John Rennie Jun 13 '18 at 16:52
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    $\begingroup$ @SRS Unless the Higgs potential changes with time it will always produce a constant energy per cubic metre, regardless of how much or how little the universe has expanded. The expansion of the universe simply doesn't enter the calculation at all. $\endgroup$ – John Rennie Jun 13 '18 at 17:04
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    $\begingroup$ @SRS From the Planck 2013 analysis we know dark matter behaves like normal pressureless matter. Well, the models with dark matter behaving like normal pressureless matter fit the CMB data. $\endgroup$ – John Rennie Jun 13 '18 at 17:09
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    $\begingroup$ The Higgs condensate is not a substance, it is just a name for the ground state in which the VEV is non-zero, so there is nothing to explain away: A zero-point energy, i.e. an energy value for a state without any particles in it, is a perfectly fine contribution to dark energy that does not contribute to stress-energy. $\endgroup$ – ACuriousMind Jun 13 '18 at 17:29

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