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I have read that the LHC, and perhaps other collides, have reached so-called electroweak energies, where the two forces are unified....

So how much energy, exactly, is needed to produce fields/particles like those that existed during the Electroweak Epoch of the early universe?

And have the W0....W3? and B bosons actually been officially 'observed'?

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    $\begingroup$ so-called electrodes energies Is that a typo? $\endgroup$
    – Ghoster
    Dec 5, 2022 at 0:46
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    $\begingroup$ @Ghoster. He means "electroweak scale energies". $\endgroup$ Dec 5, 2022 at 1:46
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    $\begingroup$ That was not a typo on MY part, dang it, but this site's (or my phone's?) Autocorrect... $\endgroup$
    – Kurt Hikes
    Jan 3, 2023 at 1:47

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Well, the popular science bloviations rarely mean anything to me, as they are pitched to impress the public with large numbers in unfamiliar units.

The electroweak scale is v=0.245 TeV, ~$2m_H$, corresponding to a temperature of ~ 2$\cdot 10^{12}$ K.

So I gather you are pointing out that the maximum LHC energy, 50 times that, should perhaps suffice to make the W&Z masses irrelevant, in some vague sense. But, in each isolated event, the vector bosons, W&Z, travel "huge" distances in our normal (post SSB, low energy) EW vacuum, before they decay and have their products reach the detectors, so what is observed (indirectly) is W&Zs.

The way I reconstruct/deconstruct your question is "can the precursors of those, $W_{1,2,3}$ & B, traveling in an effective collision fireball hotter than v be somehow inferred, before they leave that medium/vacuum and 'turn' into the 'detected' W&Z?".

I fear the question is intrinsically vague, and I have no good answer to it. The pre-SSB vacuum only obtains in the isolated "fireball" of each (rare) event, not in an extensive primordial soup.

Everything detected so far at ATLAS & CMS, to my limited knowledge, comports pretty well with the SM and its subtle predictions of the equivalence theorem for the EW interactions.

This is the systematic framework probing your massless pre-SSB bosons inside the belly of the W&Z, and parsing out the eaten goldstons in suitable amplitudes: i.e., there are small factors with v/E, so, $m_{W,Z}/E$, and they appear to be increasingly weaker at higher energies, probably borne out by the data... but maybe this is wishful thinking.

Perhaps an experimentalist could point you to a review of such. So such processes might indicate the underlying presence of $W_{1,2,3}$&B, anfractuously.

The theorist's point of view is that pre- and post-SSB variables are all equivalent, and your choosing such is a matter of convenience. The "actual" bosons "detected" in a chain of indirection, are always the massive W&Z with propagate massively in our "low-energy" vacuum.

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    $\begingroup$ "I fear the question is intrinsically vague, and I have no good answer to it." I feel like the answer could expand upon this, which to me seems like the crux of the question. The Higgs boson is also not detected directly, yet people state confidently that we have discovered it. I'm not a particle physicist, but couldn't something similar be said for the $W_i$ and $B$ bosons? $\endgroup$
    – Javier
    Dec 6, 2022 at 19:17
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    $\begingroup$ The point is W & Z and $W_i$ & B, are equivalent descriptions of the same fields. For the lab, whose vacuum is the SSB one, the first description is the best one. For certain contexts, such as calculating the evolution of couplings up to GUT scales, the second is more convenient. But both are different bases for the same vector space! The Goldstone boson equivalence theorem systematically connects the two. The one thing I am not liable to do is recast the vague question into a dozen mutually exclusive different specific ones, and answer them all! $\endgroup$ Dec 6, 2022 at 19:27
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The $W$ and $B$ fields are just linear combinations of the post-SSB fields, it's simply a choice of basis.

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