To give some context on the matter, I found these interesting articles (https://arxiv.org/abs/2007.11428 & https://arxiv.org/abs/2003.04927) where the authors analyzed, among other things, the relationship between black holes and vacuum up-tunneling events (that is, from a lower vacuum energy state to a higher one). However, I asked the authors about this, and they told me that in their particular model, they found a contradiction with thermodynamics and abandoned their model.
Despite this, I was wondering if there was another way where black holes produce similar processes (not related to the papers I cited):
I was told by Gian Francesco Giudice, director of the theoretical physics department at CERN, via email, that very energetic processes (like very high energetic cosmic rays) could excite the vacuum to a higher level (essentially, up-tunnelling it). However, cosmic rays tend to lose momentum due to the expansion of the universe, losing their peculiar velocity (similarly to how photons lose energy as they are redshifted by the cosmic expansion). However, angular momentum is conserved and not "redshifted" over time. There are massive objects in the universe with an enormous amount of angular momentum like neutron stars and rotating black holes. Since angular momentum is related to energy (for example in accretion disks, angular momentum makes them emit very energetic radiation), could these black holes transform their angular momentum into energy and cause an up-tunneling of the vacuum energy to a higher level? Could this also happen for similarly fast-rotating bodies (like neutron stars)?
And, if everything that I said above is nonsense, would there be any other way?
