Neal Weiner
@nealweiner.bsky.social
Physicist / dark matter aficionado.
The great tragedy of Science - the slaying of a beautiful hypothesis by an ugly fact. -Thomas Huxley & Oliver Wendell Jones
The great tragedy of Science - the slaying of a beautiful hypothesis by an ugly fact. -Thomas Huxley & Oliver Wendell Jones
Who is this person and what have you done with MTG?
November 16, 2025 at 3:15 PM
Who is this person and what have you done with MTG?
We should start with simple things: the stepped up basis for inheritance skews incentives in bad ways.
October 24, 2025 at 2:49 AM
We should start with simple things: the stepped up basis for inheritance skews incentives in bad ways.
This is why kids shouldn't just do one sport all the time
September 21, 2025 at 8:14 PM
This is why kids shouldn't just do one sport all the time
I mean, regardless, the high redshift universe is turning out to be interesting!
September 4, 2025 at 3:57 PM
I mean, regardless, the high redshift universe is turning out to be interesting!
So I think it's not any more contrived (and almost logically less contrived) than PBHs. It just is new and so we aren't used to it yet.
September 4, 2025 at 2:59 PM
So I think it's not any more contrived (and almost logically less contrived) than PBHs. It just is new and so we aren't used to it yet.
In principle, it's much easier to get this because late universe dynamics can enhance the density. Or isocurvature perturbations can work. Or you can have an O(1) over density in just a subcomponent of DM.
September 4, 2025 at 2:58 PM
In principle, it's much easier to get this because late universe dynamics can enhance the density. Or isocurvature perturbations can work. Or you can have an O(1) over density in just a subcomponent of DM.
I think it's not any more contrived than PBHs. PBHs say: if you have O(1) perturbations, you get a PBH. NQPBHs say: if you have a O(10^-2)-O(10^-1) perturbation, you get a BH after recombination.
September 4, 2025 at 2:57 PM
I think it's not any more contrived than PBHs. PBHs say: if you have O(1) perturbations, you get a PBH. NQPBHs say: if you have a O(10^-2)-O(10^-1) perturbation, you get a BH after recombination.
As noted in the paper however, the Qin et al "not quite primordial" black hole scenario is also viable. There, large fluctuations are seeded early but collapse post recombination.
September 4, 2025 at 8:35 AM
As noted in the paper however, the Qin et al "not quite primordial" black hole scenario is also viable. There, large fluctuations are seeded early but collapse post recombination.
You can't just leave us hanging with that question! What's the explanation?
August 10, 2025 at 12:58 PM
You can't just leave us hanging with that question! What's the explanation?
Reposted by Neal Weiner
August 9, 2025 at 12:00 PM
Go to CERN. Easy to get to with tram from the main train station. It's an inspirational place about what the world can accomplish when it works together.
July 31, 2025 at 3:24 PM
Go to CERN. Easy to get to with tram from the main train station. It's an inspirational place about what the world can accomplish when it works together.
The epitome of skating to where the puck is.
July 1, 2025 at 12:37 AM
The epitome of skating to where the puck is.
Physics student! No wonder I ended up following you.
May 22, 2025 at 2:04 AM
Physics student! No wonder I ended up following you.