Could cosmic rays induce a vacuum decay in the future?

[Suekdccia]

TL;DR Summary

Could cosmic rays induce a vacuum decay in the future (by natural means)?

I've been told that very energetic cosmic rays could cause a vacuum phase transition or vacuum decay (and even could cause a true vacuum level to go "uphill" to a false vacuum) due to their high energy levels.

I've found some references supporting this claim [1], [2], [3], [4]

But also one paper arguing that vacuum decay induced by particle collisions (such as cosmic rays collisions) would be suppressed and no amount of cosmic rays collisions occurring in nature (even in the largest production sites) could trigger such phenomenon [5]. But at the same time, the author speculates that in the future with powerful colliders we could cause a vacuum decay. However, I don't really get how the author says that a futuristic civilization could get enough energy to cause a vacuum phase transition while saying that even the most energetic events in the universe producing high-energy cosmic rays (like quasars and AGN) would fail to do so. I mean, I'm pretty sure there will be more energy in such natural events than in a particle collider even if we are talking about futuristic potential scenarios.

I asked the author from [5] about this and he said

If the Higgs instability really exists, triggering it needs putting in the same place at the same time a few hundred of very energetic Higgs bosons and (roughly) nothing else.
Natural colliders can accidentally concentrate a few random particles. This is not enough to trigger the instability. The point is that a big temperature (for example in the early universe) does not induce fast vacuum decay.
An old computation found that the thermal energy
a) allows to jump over the Higgs potential barrier, but
b) it also makes the barrier higher.
Black holes make something qualitatively similar to a big “Hawking” temperature.
People who claim that black holes trigger vacuum decay include a) but forgot to include b).
Same for scattering of particles. When many particles scatter randomly, the result is somehow similar to thermal.
To trigger the vacuum instability one needs a very special collision that only involves Higgs bosons.
This makes it too much unlikely to occur by chance.

However, I find it hard to believe that no place in the universe would achieve such conditions (especially in energetic events). I mean, for instance, it is far more likely that cellular life survives in a controlled environment by us in a lab than in a random planet (since as far as we know there is only one planet with life). The conditions for life to exist are pretty difficult to achieve in nature. However, it is possible even if very unlikely

Therefore, is it possible or not that cosmic rays collisions may trigger such a vacuum decay? And if not, or if it is unclear, could it be triggered by other mechanisms (like certain types of black holes for example)?



[1]: https://www.worldscientific.com/doi/10.1142/9789814440783_0002
[2]: https://ui.adsabs.harvard.edu/abs/2019PhRvD..99b4046C/abstract
[3]: https://theses.ncl.ac.uk/jspui/handle/10443/4907
[4]: https://www.osti.gov/etdeweb/biblio/5974966
[5]: https://arxiv.org/abs/2301.03620

 

[Mordred]

The author from 5 gave you excellent answers if you examine his paper it clearly describes his reply .
It might help to recall that paper 5 provides a thin wall scenario where number density of required Higgs bosons is roughly 1000 bosons.
Now consider the detail that the Higgs boson quickly decays with a mean lifetime of $$10^{-22} $$ s.

When you factor in number density as well as the mean lifetime determined via the Higgs cross section for the top quark case described by each paper. This should indicate just how unlikely this would be for occurring naturally.
Paper 5 also specifies that the SM model electroweak case is not a thin wall scenario.

 

[Suekdccia]

This should indicate just how unlikely this would be for occurring naturally.

I see... but in high energetic events throughout the universe (like quasars) couldn't the right conditions be met? I mean, couldn't there be enough energy to make a lot of Higgs particles in a very short time, so they achieve the density and number of particles required by the paper?

In section 5.1 the author seems to say that ultra-relativistic interactions of electrons and protons could induce dominant thermal effects. Could this then induce a vacuum decay? Could this scenario be more likely in nature, or nothing changes here?

Paper 5 also specifies that the SM model electroweak case is not a thin wall scenario

How would this affect the conclusion of the paper? Is then invalidated for our universe if the electroweak scale for SM is not a thin wall scenario? Also in section 3.2. the author says that he studied the case for a more SM-like scenario where the true vacuum lies "further apart" in the energy scale respective to the false vacuum. Then in this case are the conclusions valid?

Finally, would the arguments by the author hold in the very far future of the universe when it becomes cold, CMB has cooled down and almost all that is left are vacuum fluctuations? I mean, if we put cosmic rays colliding in these conditions, would the suppression mentioned by the paper still hold? Or in this case it would be easier to provoke a vacuum decay if particles collided?

 

[Mordred]

I honestly cannot think of a single scenario in nature occurring in our Universe today where you would get the right conditions. The thin wall case is technically the easier process as there is a lower potential difference between false and true vacuum.
Secondly such an event would be more likely in a higher density environment. Yet we have zero observational evidence of ever occurring in nature outside of Electroweak symmetry breaking.

 

[Suekdccia]

I honestly cannot think of a single scenario in nature occurring in our Universe today where you would get the right conditions.

Not even in high energetic events with a lot of energy/particle density? Could there be events in nature where a number of protons/electrons collide at high speeds that could trigger a vacuum instability (as author of [5] says in section 5.1)?

Also, would this be the same for the far-future universe? I mean, would vacuum decay still be suppressed if two (or more) particles collide with sufficient speed in a universe where everything has cooled down, is approaching heat death, and almost what is left are only quantum fluctuations? Or in this case, it would be easier?

 

[Mordred]

As stated I cannot think of any natural scenario where this could occur.