3 ms·
Yes, if it would have particle mass at the time of the big bang it would have evaporated long ago. But all small black holes do evaporate (the smaller, the fast
by corty 5y ago
Yes, if it would have particle mass at the time of the big bang it would have evaporated long ago. But all small black holes do evaporate (the smaller, the faster), so if PBHs were e.g. car-mass at the big bang, they could just be the right size for particle-masses right now (and gone in a few years).
- ben_w 5y ago1.7e11 kg is a pretty big car: https://www.wolframalpha.com/input/?i=%28%28%28h-bar%29%28c%5E4%29%28age+of+universe%29%29%2F%285120π%28G%29%5E2%29%29%5E%281%2F3%29 https://www.wolframalpha.com/input/?i=%28%28%28h-bar%29%28c%... And again, the predicted lifespan of a proton-mass black hole is significantly less than a plank time, which in turn is therefore a sign that — one way another — the maths doesn’t actually apply to that situation in the first place.
- scatters 5y agoThe minimum mass for a black hole is the Planck mass, approximately 21 micrograms. Such a black hole is a Planck length in radius, has a Hawking temperature of the Planck temperature, and will decay in Planck time, releasing Planck energy of 1.9 GJ (about the same as a tank of gasoline).