Later On

A blog written for those whose interests more or less match mine.

Archive for November 16th, 2021

Shopping trip in the sun, with flowers

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Yesterday the floodgates of heaven opened and we got a pouring rain, high winds, and much flooding of roads, with cars stalled in deep water because either (a) the driver thought that “Road Closed” did not apply to him (a specific example of the general principle some hold, that rules with which they disagree do not apply to them — cf. mask mandates, vaccination requirements), or (b) the road blockage was marked with tape strung across the road, and someone removed the tape (incredible, but it happens, repeatedly).

View out my window right now

Today, a different story: calm, sunny day, relatively warm. Totally clear skies, as you can see at the right — a photo of the new from my window right now.  (The shim in the window is to keep the window from rattling. I embrace effective solutions regardless of appearance.) I even broke out my sunglasses. 

I needed the sunglasses because, being out of greens, I walked to the local market and found some nice-looking turnip greens, turnips still attached, and at the supermarket on the way home got some red kale and green kale and mushrooms. I’ve chopped the kale and the turnip greens, and cut up the turnips, and I’m letting those sit for 45 minutes of so. Then I’ll cook them — recipe: olive oil, red onion, garlic, local fresh ginger, fresh turmeric root, mushrooms, diced lemons, greens and turnips, splash of vinegar, dash of shoyu sauce, a splash of mirin, a little water, 5 Thai red chiles chopped small, and a lot of black pepper — by now you know the drill: 200ºF for 25 minutes after everything added and simmering.

Although it’s mid-November among the intriguing plants I saw on the walk were some flowers in full bloom. The Army has a saying that in any communication with troops, 10% will not get the memo. These flowers are perhaps among the 10%. 

Notice that spherical bush. It’s perfectly symmetrical shape seems almost unnatural. In any event, it has tiny, fascinating leaves — like the leaves of the plant in the first photo, but white instead of yellow, and much smaller, like a perfect miniature.

Written by Leisureguy

16 November 2021 at 3:29 pm

Posted in Daily life

The genius of John von Neumann

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Tom Chivers writes at UnHerd:

In 1956, shortly before his early death from bone cancer, John von Neumann received a letter from Kurt Gödel, the Austrian logician. After a paragraph of half-hearted inquiries into von Neumann’s health, Gödel finally got to the point: he had found an interesting new mathematical puzzle. And in the Fifties, if you found an interesting new mathematical puzzle, you sent it to John von Neumann.

The puzzle that Gödel was describing would come to be known as P vs NP. To oversimplify, it asks: can every mathematical question which can be checked quickly also be solved quickly? For instance: you are given a half-complete Sudoku puzzle. Is there a legal solution? If someone were to show you a solution, you could quickly verify whether it was legal. If you used a larger grid, the solution would take longer to check, but not exponentially so1.

But establishing that there is a legal solution is much slower. There might be quintillions of possible ways of filling it out; the number grows exponentially with the size of the grid. Checking them all one by one might take millions of years even on a powerful computer, if the grid is large enough.

What Gödel wanted to know was: is there some algorithm that could solve the Sudoku (or similar problems) as quickly as we could check a solution? P vs NP is one of the great outstanding questions of mathematics: it has profound implications, but no one has been able to prove it, one way or the other.

The Man from the Future, Ananyo Bhattacharya’s fascinating, fast-moving intellectual biography of von Neumann, made me think of P vs NP. Not because von Neumann solved it; but because von Neumann, in Bhattacharya’s telling, provided solutions to many other previously unsolved problems, in dozens of different fields; others simply had to check them, and expand on them. There is, I think, some discomfort about calling people “geniuses” these days, or in admitting that intelligence is a real thing or that it shapes history – but von Neumann was a genius, and his extraordinary intelligence shaped the modern world.

He was not an economist, but he developed the use of fixed-point theorems in economics in a paper which the historian Roy Weintraub calls “the single most important article in mathematical economics”, and which inspired “half a dozen” Nobel laureates.

His work on game theory – he invented the field, and coined the term “zero-sum game” – inspired at least half a dozen more. Game theory also transformed the study of evolution, inspiring the work of Bill Hamilton, John Maynard Smith, and Richard Dawkins.

He developed utility theory, the basis of modern economics. In 2011 Daniel Kahneman, another economics Nobel laureate (who won his Nobel partly for building on von Neumann’s game-theory ideas), called it“ the most important theory in the social sciences”.

Some of his last work, with Stanislaw Ulam on “cellular automata” – grids of squares that turn on and off according to simple rules – shaped modern computer science in thousands of ways, notably inspiring John McCarthy, who would go on to coin the term “artificial intelligence”.

Von Neumann’s genius was apparent early. In 1915, at the age of 11, he had gone to the famous gymnasium school in his native Budapest; the “legendary” maths teacher, László Rátz, immediately realised that von Neumann was beyond his ability to teach, and sent him for extra tuition at the local university. There he was mentored by Gábor Szegö, later head of Stanford’s maths department, who was “moved to tears” by his brilliance.

At 17, still at high school, he partly rescued Cantor’s set theory, the basis of much mathematical theory, from a crippling paradox. A couple of years later, he helped reconcile Werner Heisenberg and Erwin Schrödinger’s rival models of quantum mechanics. In the early Thirties, he met the astronomer Subrahmanyan Chandrasekhar, and worked with him on general relativity and the behaviour of stellar clusters. Chandrasekhar would later tell an interviewer, “If I say, ‘He reminds me of von Neumann,’ that’s about the best compliment I can give anyone.”

Von Neumamm read some Alan Turing research which imagined a hypothetical computing machine, and saw how to build a working computer. The paper he produced building on Turing’s ideas is considered “the birth certificate of modern computers”, according to the computer scientist Wolfgang Coy. With his wife Kläri, and Ulam, he pioneered Monte Carlo simulations, vital now in climate modelling and a million other fields.

In almost every sphere of scientific inquiry – physics, biology, maths, economics, the social sciences, computing – you find von Neumann’s fingerprints. There is a Wikipedia page of “List of things named after John von Neumann.” Were it not for him, our understanding of the world would be decades behind where it is.

What created this genius? Bhattacharya  . . .

Continue reading.

Written by Leisureguy

16 November 2021 at 12:50 pm

The Wrong Way to Set Speed Limits

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Naturally enough, the way speed limits are typically set in the US and Canada is (a) wrong and (b) doesn’t work. After watching this, it struck me that this is a User-Experience (UX) design issue.

Written by Leisureguy

16 November 2021 at 12:44 pm

The Drunken Goat, the Pro 48, and a great shave

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Little by little my supply of Mickey Lee Soapworks’ The Drunken Goat dwindles, but that’s life. I did get a noble lather this morning, thanks to my trusty Pro 48, and the Charcoal clone of the Edwin Jagger head delivered a fine shave, here mounted on a Wolfman razor handle. 

Three passes to a very smooth result, then a splash of the aftershave, and a brilliantly sunny morning begiins.

Written by Leisureguy

16 November 2021 at 9:57 am

Posted in Shaving

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