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by pdonis 650 days ago
> the entire theory of the higgs field and its discovery came from understanding that the model without it lacked sufficient gravity to match the world around us.

No, it didn't. Mass is not required for gravity; only energy is. The energy was there before the electroweak phase transition; it just wasn't in the form of rest mass. It still produced gravity.
2 comments
LegitShady 650 days ago
The end of the electroweak epoch is estimated at 10^-12 seconds after the big bang. So while I understand that something existed prior to the universe as we understand it now, for the overwhelming majority of the existence of reality we have lived in a reality after the electroweak phase transition, and the universe we live in today and the features we recognize of it are a result of forces including the effect of the higgs field on mass and thus gravity.

So you're right technically, but it has nothing to do with what I said in my first comment - without the higgs field the universe as we know it today would be unrecognizable, and a universe without a higgs field would not look like ours.

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pdonis 649 days ago
> and thus gravity.

No. The electroweak phase transition had no effect on gravity whatever; the stress-energy that was governing the expansion was the same before and after. Again, the source of gravity in GR is the stress-energy tensor, not rest mass.

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leptons 649 days ago
>Mass is not required for gravity; only energy is.

E = MC^2

Can't have energy without mass, and mass leads to gravity.

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elashri 649 days ago
Actually it is

E^2 = (MC)^2 + (PC^2)^2

The first term is describing the rest mass. You can redefine the mass term to make it E=mc^2 but now this mass does not correspond to the rest mass. And for sure you can have energy without having a rest mass. Actually for the early universe all you had was a form of radiation and energy.

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itishappy 649 days ago
The full equation is: E^2 = (p*c)^2 + (m0*c^2)^2.

https://en.wikipedia.org/wiki/Energy%E2%80%93momentum_relati...

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damiankennedy 649 days ago
This ignores Planck's energy-frequency relation. Things like photons are affected by gravity as well.
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pdonis 649 days ago
> E = MC^2

Is only an approximation for particular cases, not a general law.

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