I Number of Higgs "particles" per unit volume

[mister i]

TL;DR Summary

Is the number of Higgs "particles" per unit volume constant?

Is the number of Higgs "particles" per unit volume constant (or Higgs field value), even in expanding space?

 

[PeterDonis]

the number of Higgs "particles" per unit volume

...is not even a meaningful quantity. The Higgs field is not even in a state with a meaningful "particle number" except in special cases like the interior of the LHC during an experimental run.

 

[ohwilleke]

...is not even a meaningful quantity. The Higgs field is not even in a state with a meaningful "particle number" except in special cases like the interior of the LHC during an experimental run.

There is also a distinction between interactions with on-shell Higgs bosons v. interactions with off-shell Higgs bosons (i.e. virtual Higgs bosons).

But, while the particle part of the question is ill-posed, the question asking "Is the . . . Higgs field value [constant] . . ., even in expanding space?" Is not non-sensical on its face.

 

[PeterDonis]

the question asking "Is the . . . Higgs field value [constant] . . ., even in expanding space?" Is not non-sensical on its face.

Even the "Higgs field value" is problematic since a quantum field is not a number, it's an operator. But asking about something like the average energy density of the Higgs field would be reasonable. As far as I know that is constant as the universe expands, like dark energy density.

 

[Vanadium 50]

...is not even a meaningful quantity.

Or it's zero pretty much everywhere.

Add "scare quotes" as necessary.