Ana Alexandre and Valentin Thoss tell us about their recent papers examining the consequences of a potential “memory burden” effect on decaying primordial blackholes (PBHs).

This memory burden effect would be a consequence of quantum gravity and would substantially slow down the Hawking evaporation of blackholes. The consequences for primordial blackholes would be very important because it would open a whole window of PBH masses as dark matter candidates. (Masses that are normally ignored because PBHs of these masses are presumed to have decayed by today.)

All fundamental physicists would agree that Hawking radiation must breakdown at some point at/before a blackhole reaches the Planck mass. This proposed memory burden effect goes a step further and claims that the breakdown must happen no later than when a blackhole has decayed to half of its original mass. This is not universally agreed upon, but it’s still worth examining the consequences if it is true.

Ana: at linkedin
Valentin: at Max Planck Inst

Ana’s paper: arXiv: 2402.14069
Valentin’s paper: arXiv: 2402.17823