0
$\begingroup$

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.

Improve this question
$\endgroup$
9
  • 1
    $\begingroup$ Possible duplicate of Why is the Standard model Higgs not a candidate of dark matter (in particular, a WIMP)? (by OP), and Is cold dark matter made of Higgs bosons?. $\endgroup$
    – AccidentalFourierTransform
    Commented Jun 13, 2018 at 15:32
  • $\begingroup$ The question is not why Higgs boson is not a dark matter. The question is why can't the Higgs condensate behave as dark matter. Please understand it's not a duplicate. @AccidentalFourierTransform $\endgroup$
    – SRS
    Commented Jun 13, 2018 at 15:34
  • $\begingroup$ I don't see how those questions are different. $\endgroup$
    – AccidentalFourierTransform
    Commented Jun 13, 2018 at 15:35
  • $\begingroup$ Why the beyond-the-standard-model tag? $\endgroup$
    – John Rennie
    Commented Jun 13, 2018 at 17:13
  • 2
    $\begingroup$ Your question is unclear. The "Higgs condensate" is simply a name for the symmetry-breaking ground state in which the Higgs VEV is non-zero, it does not denote any actual substance that could "clump", "move" or otherwise be "found" anywhere. $\endgroup$
    – ACuriousMind ♦
    Commented Jun 13, 2018 at 17:18

1 Answer 1

Reset to default
2
$\begingroup$

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.

Improve this answer
$\endgroup$
7
  • $\begingroup$ How does it differ from dark matter? @JohnRennie $\endgroup$
    – SRS
    Commented Jun 13, 2018 at 16:49
  • $\begingroup$ @SRS I've extended my answer to address this $\endgroup$
    – John Rennie
    Commented Jun 13, 2018 at 16:52
  • 2
    $\begingroup$ @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
    Commented Jun 13, 2018 at 17:04
  • 2
    $\begingroup$ @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
    Commented Jun 13, 2018 at 17:09
  • 2
    $\begingroup$ 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 ♦
    Commented Jun 13, 2018 at 17:29

Not the answer you're looking for? Browse other questions tagged or ask your own question.