Does electroweak symmetry breaking involve quantum tunneling, just like GUT symmetry breaking?
What makes you think tunneling has anything at all to do with symmetry breaking?
According to inflation theory, GUT symmetry breaking involves the decay of fale vaccum through quantum tunneling. So does electroweak symmetry breaking also involve quantum tunneling?
No it doesn't. You can have inflation without GUTs. Or for that matter, without ordinary matter (although in that case it would be hard to tell. Your premise is incorrect, so your question has no answer.
This is not correct. Inflation theory has nothing to do with GUT symmetry breaking; GUT symmetry breaking happens after the end of inflation.
Also, although the original "old inflation" models involved the decay of a false vacuum by tunneling, those models were found not to be viable. Newer inflation models have inflation ending by a "slow roll" transition that involves no tunneling.
As noted, the OP question is based on a false premise, so this thread is closed.
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