What products use PFAS whose absence would cause society to collapse? If you look at the major sources of PFAS by 3M, it's not like these were essential products. Here's a random list from wisconsin.gov:
Cleaning products.
Water-resistant fabrics, such as rain jackets, umbrellas and tents.
Grease-resistant paper.
Nonstick cookware.
Personal care products, like shampoo, dental floss, nail polish, and eye makeup.
Stain-resistant coatings used on carpets, upholstery, and other fabrics.
I also play some, and yeah that's incorrect. Also, there was recently a bunch of hype about an adversarial strategy that could beat AIs w/o deep readout (i.e. only using the 'policy network' nonlinear ML stuff and not enough actual calculation). Here's a vid of an amateur doing it.
Also, if you want to get into it, Micheal Redmond's Go TV on youtube has an amazing beginner playlist, watch some of that then maybe blacktoplay.com and if you likey play :)
Definitely not true in math - if you take a circle (S^1 = { (x, y) : x^2 + y^2 == 1 }) it has a hole as defined by homotopy in the middle and there is no 'space' there. If you fill it with space you get a disk (D^2 = { (x, y) : x^2 + y^2 <= 1 }) there is no longer a hole as defined by homotopy/is contractible.
I thought the same thing when I noticed he's an economist - though I do understand what he's saying - the furin cleavage site is suspicious AF. For example
"""
Furin cleavage sites are also found in certain bat-origin MERS-like merbecovirises, but not—with the exception of SARS-CoV-2—in the sarbecovirus lineage. The presence of a furin cleavage motif at the SARS-CoV-2 S1–S2 interface is therefore highly unusual, leading to the smoking gun hypothesis of manipulation that has recently gained considerable attention as a possible origin of SARS-CoV-2. However, with analogy to influenza, it was shown many years ago that the simple insertion of a polybasic site into an H3 virus does not result in a high pathogenicity phenotype7 and is likely to only function in the context of a series of other genomic changes provided by a process of natural selection. """
i.e. an actual scientist is saying it's suspicous (sort of), and his only rebuttal to that point of view is "just that doesn't guarantee anything". If scientists WERE doing this (which they probably were/are), it makes sense that while it doesn't guarantee anything, if they did get lucky and achieve a highly pathogenic phenotype and it were to contaminate something, that'd be that.
What I really don't understand is why this is so abjectly anti-US: US scientists trained Chinese ones in biotech, and they fucked up, and that's the US's fault? So if the US helps china, they're bad, and if they don't and 'try to contain china', they're bad too. Ok. Note this guy has been criticized for his stances on China. Hard to say whether that's reasonable or nationalist backlash, but this doesn't help IMO.
Cleaning products. Water-resistant fabrics, such as rain jackets, umbrellas and tents. Grease-resistant paper. Nonstick cookware. Personal care products, like shampoo, dental floss, nail polish, and eye makeup. Stain-resistant coatings used on carpets, upholstery, and other fabrics.