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mjreacheron The exceptional Jordan algebra (2020)

I wonder if there is any connection of this being on the front page today with this paper [0] being uploaded on arXiv today or if it's just pure coincidence.

[0]: https://arxiv.org/abs/2503.10744

mjreacheron Klára Dán von Neumann

Marina vN Whitman had the book in her possession so I suppose they visited her and got access to it that way. I emailed her back in 2022 about it and she said she was planning on sending it to Josh Levy at the Library of Congress to go with the von Neumann/Klara papers there but I don't know how that ended up going, perhaps the book might be there now.

In a similar fashion Vincent Ford, who was the Air Force colonel responsible for von Neumann when he was in hospital dying of cancer, published a manuscript, Twenty-Four Minutes To Checkmate, on the US crash program for ICBMs focusing on the 1953-1957 period, which obviously overlaps a lot with when von Neumann was involved in those topics. It's held in the Dwight Eisenhower Library in Kansas however it's also only available if you visit in person.

It would be a great boost to the history of science if both texts were either published or scanned and uploaded online to make them significantly more accessible to both scholars and interested laypersons.

mjreacheron Klára Dán von Neumann

I've seen her unpublished memoir, A Grasshopper in Very Tall Grass, quoted in quite a few places and it definitely seems worth publishing, such a shame no publisher has taken any interest in it yet.

mjreacheron Potential Links Between the Wuhan Institute of Virology and Origin of Covid [pdf]

A short thread giving an overview of the report mandated by Congress:

https://twitter.com/jseldin/status/1672390899718840322

mjreacheron A New Theory for the Assembly of Life in the Universe

By the sounds of that article there needs to be more work done on applying abstract notions of complexity to the real world and developing suitable methods for this.

mjreacheron The military loved Discord for Gen Z recruiting. Then the leaks began

Parent post doesn't distinguish between those. It just annoys to see people always talking about governmental or corporate bureaucracy but when it comes to intelligence agencies suddenly it's like they're immune to it and become perfect panopticons of information gathering and analysis.

mjreacheron U.S. may change how it monitors the web after missing leaked documents for weeks

> spying on allies

That is one of the exact purposes those agencies exist for in almost every country of the world.

> possibly misleading the public about casualty numbers

The numbers given in the documents are consistent with the numbers publicly stated by the US military.

> demanding an investigation

For what? I don't see how he is a whistleblower when he hasn't exposed any illegal activity. It's pretty clear from what he friends said that he was doing this solely to impress his friends, which is pretty clearly illegal.

mjreacheron The military loved Discord for Gen Z recruiting. Then the leaks began

Ukraine's Western supporters can propose a ceasefire but why would either side agree to one? Putin seems to be in it for the long haul, he probably knows Western support for Ukraine will gradually go down and then once Russia's military recovers a bit they can go back their original aim of taking all of Ukraine. For Zelenskyy there exists plenty of popular support for trying to take back territory, and unless the US says they'll completely throw them to the wolves and cut off all aid (which would make the US look completely terrible internationally), why would he agree to a ceasefire if he thinks Russia will go back to war once they recover anyway?

mjreacheron The military loved Discord for Gen Z recruiting. Then the leaks began

They literally openly admitted it last November. You can say the special forces part is new but that isn't the point being made by most, which is about US troop boots on the ground, and the military never says which specific type of troops are there anyway for operational security reasons.

https://www.nbcnews.com/news/us-news/us-military-inspectors-...

mjreacheron The military loved Discord for Gen Z recruiting. Then the leaks began

If ICs were already all over major social media like Discord, then how did these leaks sit spread around unnoticed for almost half a year? I swear every time this comes up people's critical thinking just vanishes into thin air. Mythologizing intelligence agencies as these omniscient entities only benefits them.

mjreacheron Thinking hard makes the brain tired

On the contrary, John von Neumann was not known to sleep much at all and he was well known for being the fastest thinker alive in his time.

mjreacheron South Korea Now Openly Discussing Arming Itself with Nuclear Weapons

The War Zone is a well reputed publication for defense news so I'm not sure why you're making this comment? The fact it publishes under The Drive has nothing to do with the author and hence quality of the content.

mjreacheron A non-constructive proof of the Four Colour Theorem

Some comments on the math subreddit by some folks going through the proof in case anyone with a more formal background is interested:

https://old.reddit.com/r/math/comments/zruc58/221209835_a_no...

mjreacheron We are drowning in information while starving for wisdom (2021)

This issue has been talked about quite a bit over the past few years and to me it comes down fundamentally to incentives academics have to keep churning papers because that's what they get measured on. Of course the good thing about that is that you can change the incentives, just as how science funding changed significantly post WW2, but I'm afraid just like in many problematic areas of society nowadays there is a large group of people who benefit from this situation and are hence hostile to any sort of change. As such if change does come I think it will have to be top down rather than bottom up.

For an interesting perspective the physicist Murray Gell-Mann spoke on similar issues in a 1997 interview:

https://www.youtube.com/watch?v=tQGjsWiA_mM

mjreacheron The sad story of Heisenberg's doctoral oral exam (1998)

Dirac came from a later generation than Einstein. For example during Einstein's annus mirabilis (1905) I doubt very many physicists knew of tensor calculus considering it was only developed a decade beforehand. During that time the mathematics physicists learnt was very much the traditional topics of analysis: series expansions, special functions, integral equations, calculus of variations, quadratic forms and of course partial differential equations. Hilbert himself actually wrote a textbook with Richard Courant covering these topics: Methods of Mathematical Physics. As such I don't really think many physicists of Einstein's generation knew lots of mathematics simply because it wasn't taught at the time. In the decades since physicists gradually has generally become more "mathematised" so to speak. In Dirac's generation tensor calculus and group representation theory became important, than in general abstract algebra and functional analysis, then as differential geometry became more well developed that gets taught and closer to the modern day you can find top theoretical physics students learning all sorts of abstract mathematics like algebraic topology.

mjreacheron The sad story of Heisenberg's doctoral oral exam (1998)

This reminds me of how Terence Tao almost failed his orals at Princeton. Turns out even the best in the field need to spend lots of time doing hard work.

https://web.math.princeton.edu/generals/tao_terence

https://www.ams.org/journals/notices/202007/rnoti-p1007.pdf (less technical)

mjreacheron ZLibrary domains have been seized by the United States Postal Inspection Service

I'm reading on the zlibrary subreddit that supposedly there were some popular (>300k views) TikToks going around showing that you could use z-lib to get free books. https://torrentfreak.com/tiktok-blocks-z-library-hashtag-pen...

I wonder if this is related.

mjreacheron Vladimir Putin says the world’s energy infrastructure is at risk

https://www.crn.com/news/security/zscaler-ceo-major-eu-inter...

Title: Zscaler CEO: ‘Major’ EU Internet Cable Cut Was ‘Act Of Vandalism’

Most incidents of cuts in internet cables usually have benign causes but given recent hostilities it's worth keeping an eye on whether these incidents start becoming far more common than they have been historically.

mjreacheron Cloudflare Calls

I for one think this could be a very useful idea for my use case (education) and am looking forward to see how it turns out.

mjreacheron If the Moon Were Only 1 Pixel (2014)

> This also holds for small things like atoms. They are mostly empty space, too

Not quite so simple, see: https://physics.stackexchange.com/questions/126512/why-doesn...

mjreacheron Intelligence and radical economic attitudes

Well that's what we would like to think of ourselves.

mjreacheron Mudge Twitter whistleblower testimony [video]

On another thread that didn't receive the same attention as this one we learn the Twitter has Chinese and Indian government agents amongst their employees.

https://news.ycombinator.com/item?id=32825670

mjreacheron Riemann Hypothesis Disproved?

Yes you would be right I haven't taken a class on analytic number theory. Perhaps excuse my lack of knowledge on the subject but why would psi(x)=0 for x in [1, 2)? Λ(2) is not 0. You are right that arXiv moderators don't review papers in the sense of peer review but they still check over them and I haven't heard of an occasion where something that was originally placed in General Mathematics or General Physics was later moved to another category. Safe to say if there was anything substantial in the proof we would have heard of something from the experts in number theory by now.

mjreacheron Are all brains good at math?

One thing I think would be interesting to research is how different people are good in different areas of math. There's lots of anecdotal evidence[0] of people saying they tend to be good at either more algebraic subjects (say group theory or algebraic number theory) or more analytical ones (PDEs or measure theory) likewise I would extend this to also include geometric/topological subjects.

In general especially as once gets into more advanced mathematics the abstraction level gets much higher quite quickly so it would interesting to know if there is any connection between brain structures and ability to grasp abstract mathematics. As an example I know a physicist who can tell you everything about general relativity and has a solid grasp of differential geometry but one time I was trying to teach him some mathematical logic and he just couldn't grok it no matter how many hours we spent on it. Likewise subjects that use category theory heavily (homological algebra/algebraic geometry for example) are known to be difficult to understand even for professional mathematicians in other areas.

[0]: https://bentilly.blogspot.com/2010/08/analysis-vs-algebra-pr...

mjreacheron Riemann Hypothesis Disproved?

I was referring to the ones in Motl's blog. I wasn't aware this paper was updated compared to that one to remove those problems. Either way, looking at the paper I see a few things I can't follow. For example for theorem 1 he says for d>0 there exists \psi(y) = some expression uniformly for y≥1. The source he quotes is Montgomery's book on multiplicative number theory. Looking at the theorem in that book (Theorem 6.9) I can't see how what he says follows from it. The book is looking at the distribution of prime numbers with some error bounds. There is nothing in the paper about any sort of error bounds. Quite often such papers when submitted to arXiv get a quick look-over and if the professional mathematicians don't think it's worth much it gets thrown into the "General Mathematics" section, whereas more legitimate attempts would be put in the number theory section.

mjreacheron LibGen's Bloat Problem

This is a pretty common one I see:

https://www.pdf-tools.com/en/products/pdf-optimizer/

When I mean optimized I mean maintaining the page quality too. Obviously you can make the PDF look like crap but that's not very useful.

mjreacheron LibGen's Bloat Problem

I think one of the problems is the lack of a good open source PDF compressor. We have good open source OCR software like ocrmypdf which I've seen used before, but some of the best compressed books I've seen on libgen used some commercial compressor while the open source ones I've used were generally quite lackluster. This applies double so when people are ripping images from another source, combining them into a PDF then uploading as a high resolution PDF which inevitably ends up being between 70-370 MB.

How to deal with duplication is also a very difficult problem because there's loads of reasons why things could be duplicated. Take a textbook, I've seen duplicates which contain either one or several of the following: different editions, different printings (of any particular edition), added bookmarks/table of contents for the file, removed blank white pages, removed front/end cover pages, removed introduction/index/copyright/book information pages, LaTeX'd copies of pre-TeX textbooks, OCR'd, different resolution, other kinds of optimization by software that reduces to wildly different file sizes, different file types (eg .chm, PDFs that are straight conversions from epub/mobi), etc. Some of this can be detected by machines, eg usage of OCR but some of the other things aren't easy at all to detect.

mjreacheron Riemann Hypothesis Disproved?

https://www.google.com/search?q=riemann+hypothesis+site%3Avi...

If you've studied real analysis some of the integrals don't converge the way the paper claims they do (I think Lubos makes similar comments on the page you linked in one of the sister comments).

mjreacheron ‘Generation sensible’ risk missing out on life experiences, therapists warn

study in question:

https://onlinelibrary.wiley.com/doi/10.1111/1468-4446.12964

mjreacheron Riemann Hypothesis Disproved?

There have been lots of attempts by people trying to solve the RH and quite a few of them use the exact same kind of circular logic that is demonstrated in the paper.