Later On

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

Archive for March 11th, 2021

Are millets healthy grains?

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Update: If you order millet, be sure that you get unpolished millet. Unpolished millet is the intact whole grain; polished millet removes the bran. Ceylon Grocer, for example, lists their unpolished millets.

Update: It’s worth noting that millets, like flax, soy, and broccoli, are goitrogenic. That is totally not a problem if you get adequate iodine (which I get by beating two sheets of nori a day as a snack). Don’t let that put you off millet any more than you should let it put you off broccoli. See this post.

Written by Leisureguy

11 March 2021 at 8:31 pm

Losing cause and effect in physics seems like losing associativity in abstract algebra — but there it is

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And some interest math arises as the common properties of arithmetic operations are abandoned. The requirement that the square of any number be positive was set aside with the creation/discovery of i and the complex numbers, which turned out be very useful. Losing commutativity happens pretty quickly as you develop new numbers. Although complex numbers are commutative (a*b = b*a for any two complex numbers a and b), quaternions are not, though with quaternions associativity (a*(b*c) = (a*b)*c) still holds (as it does for complex numbers, real numbers, rational numbers, and integers. But with octonions you lose associativity as well. (Real numbers are, well, real numbers. Complex numbers are represented by pairs of real numbers, quaternions by quadruples of real numbers, an octonions by octuples of real numbers.)

Associativity is pretty basic, as is cause and effect, but exploring reality is like moving west on the Oregon Trail: some things must be abandoned along the way. Special relativity did away with simultaneity, and now we lose cause and effect. Natalie Wolchover writes in Quanta:

Alice and Bob, the stars of so many thought experiments, are cooking dinner when mishaps ensue. Alice accidentally drops a plate; the sound startles Bob, who burns himself on the stove and cries out. In another version of events, Bob burns himself and cries out, causing Alice to drop a plate.

Over the last decade, quantum physicists have been exploring the implications of a strange realization: In principle, both versions of the story can happen at once. That is, events can occur in an indefinite causal order, where both “A causes B” and “B causes A” are simultaneously true.

“It sounds outrageous,” admitted Časlav Brukner, a physicist at the University of Vienna.

The possibility follows from the quantum phenomenon known as superposition, where particles maintain all possible realities simultaneously until the moment they’re measured. In labs in Austria, China, Australia and elsewhere, physicists observe indefinite causal order by putting a particle of light (called a photon) in a superposition of two states. They then subject one branch of the superposition to process A followed by process B, and subject the other branch to B followed by A. In this procedure, known as the quantum switch, A’s outcome influences what happens in B, and vice versa; the photon experiences both causal orders simultaneously.

Over the last five years, a growing community of quantum physicists has been implementing the quantum switch in tabletop experiments and exploring the advantages that indefinite causal order offers for quantum computing and communication. It’s “really something that could be useful in everyday life,” said Giulia Rubino, a researcher at the University of Bristol who led the first experimental demonstration of the quantum switch in 2017.

But the practical uses of the phenomenon only make the deep implications more acute.

Physicists have long sensed that the usual picture of events unfolding as a sequence of causes and effects doesn’t capture the fundamental nature of things. They say this causal perspective probably has to go if we’re ever to figure out the quantum origin of gravity, space and time. But until recently, there weren’t many ideas about how post-causal physics might work. “Many people think that causality is so basic in our understanding of the world that if we weaken this notion we would not be able to make coherent, meaningful theories,” said Brukner, who is one of the leaders in the study of indefinite causality.

That’s changing as physicists contemplate the new quantum switch experiments, as well as related thought experiments in which Alice and Bob face causal indefiniteness created by the quantum nature of gravity. Accounting for these scenarios has forced researchers to develop new mathematical formalisms and ways of thinking. With the emerging frameworks, “we can make predictions without having well-defined causality,” Brukner said.

Correlation, Not Causation

Progress has grown swifter recently, but many practitioners trace the origin of this line of attack on the quantum gravity problem to work 16 years ago by Lucien Hardy, a British-Canadian theoretical physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada. “In my case,” said Brukner, “everything started with Lucien Hardy’s paper.”

Hardy was best known at the time for taking a conceptual approach made famous by Albert Einstein and applying it to quantum mechanics.

Einstein revolutionized physics not by thinking about what exists in the world, but by considering what individuals can possibly measure. In particular, he imagined people on moving trains making measurements with rulers and clocks. By using this “operational” approach, he was able to conclude that space and time must be relative.

In 2001, Hardy applied this same approach to quantum mechanics. He reconstructed all of quantum theory starting from five operational axioms.

He then set out to apply it to an even bigger problem: the 80-year-old problem of how to reconcile quantum mechanics and general relativity, Einstein’s epic theory of gravity. “I’m driven by this idea that perhaps the operational way of thinking about quantum theory may be applied to quantum gravity,” Hardy told me over Zoom this winter.

The operational question is: In quantum gravity, what can we, in principle, observe? Hardy thought about the fact that quantum mechanics and general relativity each have a radical feature. Quantum mechanics is famously indeterministic; its superpositions allow for simultaneous possibilities. General relativity, meanwhile, suggests that space and time are malleable. In Einstein’s theory, massive objects like Earth stretch the space-time “metric” — essentially the distance between hash marks on a ruler, and the duration between ticks of clocks. The nearer you are to a massive object, for instance, the slower your clock ticks. The metric then determines the “light cone” of a nearby event — the region of space-time that the event can causally influence.

When you combine these two radical features, Hardy said, two simultaneous quantum possibilities will stretch the metric in different ways. The light cones of events become indefinite — and thus, so does causality itself.

Most work on quantum gravity elides one of these features. Some researchers, for instance, attempt to characterize the behavior of “gravitons,” quantum units of gravity. But the researchers have the gravitons interact against a fixed background time. “We’re so used to thinking about the world evolving in time,” Hardy noted. He reasons, though, that quantum gravity will surely inherit general relativity’s radical feature and lack fixed time and fixed causality. “So the idea is really to throw caution to the wind,” said the calm, serious physicist, “and really embrace this wild situation where you have no definite causal structure.”

Over Zoom, Hardy used a special projector to film a whiteboard, where he sketched out various thought experiments, starting with one that helped him see how to describe data entirely without reference to the causal order of events.

He imagined an array of probes drifting in space. They’re taking data — recording, say, the polarized light spewing out of a nearby exploding star, or supernova. Every second, each probe logs its location, the orientation of its polarizer (a device like polarized sunglasses that either lets a photon through or blocks it depending on its polarization), and whether a detector, located behind the polarizer, detects a photon or not. The probe transmits this data to a man in a room, who prints it on a card. After some time, the experimental run ends; the man in the room shuffles all the cards from all the probes and forms a stack.

The probes then rotate their polarizers and make a new series of measurements, producing a new stack of cards, and repeat the process, so that the man in the room ultimately has many shuffled stacks of out-of-order measurements. “His job is to try to make some sense of the cards,” Hardy said. The man wants to devise a theory that accounts for all the statistical correlations in the data (and, in this way, describes the supernova) without any information about the data’s causal relationships or temporal order, since those might not be fundamental aspects of reality.

How might the man do this? He could first . . .

Continue reading.

Written by Leisureguy

11 March 2021 at 6:36 pm

Posted in Daily life, Math, Science

Not only wolves, but goats as well

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Reference is to this post.

Written by Leisureguy

11 March 2021 at 6:02 pm

The Jewelry Archaeologist

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Just by accident a segment of cultural knowledge was preserved. Alison Main writes in Craftsmanship Quarterly:

  1. The Search, Stage One
  2. The Evolution of Gold
  3. Catch Me If You Can
  4. “I Pay Cash For Hubs”
  5. “One More Vulture”
  6. The “Mad Dog Marxist”
  7. The Fruits of Loyalty
  8. The Question of Originality
  9. Tomorrow’s Vintage Jewelry

On a summer vacation in 1995, in Providence, Rhode Island, Hugo Kohl noticed an intriguing item on a local tourist map. A pictorial inset, blown up to highlight a piece of the city’s historic center, said “Providence Jewelry District.” Kohl happened to have been working in the jewelry business at the time, as a goldsmith back in Harrisonburg, Virginia. With his wife and daughter out shopping on the town, Kohl hopped in his car. Once he reached the Jewelry District, he discovered … nothing: just some dilapidated old factories and run-down warehouses. Something, he thought, is not adding up.

This was a decade before Google maps, so Kohl’s most immediate mode of assistance was a nearby telephone booth. Flipping through the Providence Yellow Pages, Kohl unearthed a few jewelry businesses still in existence and made some calls. One was a company that dealt with factory-scale jewelry manufacturing equipment, and he persuaded the owner to let him visit. After a quick tour, the factory owner left Kohl on his own to “snoop around.”

Kohl soon happened upon a team of warehouse workers with a forklift, who were heaving broken boxes of steel parts into a dump truck. While one load was going into the truck-bed, a small, rusted, antique metal cabinet fell apart, and a bunch of dirty metal trinkets spilled out. Some fell on the ground right at Kohl’s feet. As the workers were scooping up the spill and throwing the pieces into the dump truck, Kohl picked up a few, then stood there in awe. “Each one of these pieces was like a little mini Michelangelo,” Kohl recalls. “They were beautiful carvings. I knew nothing of what I had, but I did intimately know the jewelry connected to this art.”

For Kohl, this was an out-of-body moment—a combination of shock, surprise, amazement, and confusion. Why would anyone throw away such masterful tiny sculptures? “To factory owners, it was just stuff,” he says. “It was nothing. It was trash. The only value it held for them was what it could sell for scrap.”

As the truck drove away from the warehouse, Kohl panicked. “I ran, hopped in my car, and I followed the dump truck onto the highway. It was summer. My windows were down. I was speeding down Interstate 95. Cars were zooming all around me, and I pulled up alongside the truck, blasting my horn, trying to catch the driver’s attention. I waved him down, pointing to the back of his truck. He thought I was telling him something was wrong with his truck, that there was an emergency, so he pulled over.”

Kohl soon happened upon a team of warehouse workers with a forklift, who were heaving broken boxes of steel parts into a dump truck. While one load was going into the truck-bed, a small, rusted, antique metal cabinet fell apart, and a bunch of dirty metal trinkets spilled out. Some fell on the ground right at Kohl’s feet. As the workers were scooping up the spill and throwing the pieces into the dump truck, Kohl picked up a few, then stood there in awe. “Each one of these pieces was like a little mini Michelangelo,” Kohl recalls. “They were beautiful carvings. I knew nothing of what I had, but I did intimately know the jewelry connected to this art.”

For Kohl, this was an out-of-body moment—a combination of shock, surprise, amazement, and confusion. Why would anyone throw away such masterful tiny sculptures? “To factory owners, it was just stuff,” he says. “It was nothing. It was trash. The only value it held for them was what it could sell for scrap.”

As the truck drove away from the warehouse, Kohl panicked. “I ran, hopped in my car, and I followed the dump truck onto the highway. It was summer. My windows were down. I was speeding down Interstate 95. Cars were zooming all around me, and I pulled up alongside the truck, blasting my horn, trying to catch the driver’s attention. I waved him down, pointing to the back of his truck. He thought I was telling him something was wrong with his truck, that there was an emergency, so he pulled over.”

As soon as they both got out of their vehicles, Kohl made him an offer. “You’ve got some stuff on the back of your truck that I’d like to buy,” he said. Fortunately (or unfortunately for his wife) Kohl had a large portion of his family’s vacation fund in his pocket—about $1,500 in cash. In his eyes, however, this was a chance for a priceless deal, far more valuable than a handful of gourmet dinners. Kohl laid ten $100 bills on the hood of his car, methodically placing one bill on top of the other. He wanted the driver to see the money, to take it all in. Then Kohl grabbed the stack of cash, ripped the bills in half, placed one half in the driver’s hand, held the other half in his hand, and said, “If you let me get something from the back of your truck, I’ll give you the other half.”

Incredulous but curious, the driver agreed. For the next couple of hours, in the New England humid summer heat, Kohl hauled stuff off the dump truck in search of his hoped-for treasures. Once he gathered these little nuggets, he gave the driver the second half of the money, threw the loot in his truck, finished up his vacation (his wife was bemused, yet supportive of this whimsy), and went home to Harrisonburg to unearth his stash. “All this stuff was rusted,” Kohl said. “It was nasty, disgusting, gross. I cleaned it off, looked at these tiny pieces of steel, unsure what I just bought. I had no answers, but I knew I had something very special.” Eventually, Kohl figured it out. “What I stumbled into,” he now says, “was the very end of this industry coming undone. If I’d been a year later, none of this would be here. I ended up there at the exact right moment to intervene.”

THE SEARCH, STAGE ONE

To put the puzzle together, Kohl embarked on an epic quest for information. He bought a digital camera, piles of blank CD-ROMs (the photo transfer technology of the day), and took photo after photo of his decaying booty. After burning them on the CDs and composing query letters, he spent months mailing it all to jewelry experts and academics. He called Sotheby’s, Christie’s, the Smithsonian. “I put hundreds of these CDs out there in the world,” Kohl recalls. They’re still out there. I sent them to every university that had a metals and jewelry department.” In his letters, Kohl asked, “What is this? How was it used?” The response: Zilch. No answers. No leads.

Exasperated, Kohl called the only lead he had—Tony Santoro, the man whose Providence factory led Kohl to his loot. “They’re hubs,” Santoro said. “They’re worthless.”

Hubs, Kohl soon learned, are actual size, three-dimensional renderings of how a finished piece of vintage jewelry would take shape. Given how important these little blocks of steel once were, Kohl would not accept Santoro’s answer. To placate Kohl, Santoro gave him a few names, but no one wanted to talk. Finally, on a subsequent trip to Providence, during a visit to Gold Machinery, the office manager said, “You could probably talk to Peter.” When Kohl asked for Peter’s phone number, the manager said, “I can’t. Peter will kill me if I give you his number.” By this point, the jewelry trail had been cold for far too long for Kohl to put up with another dead end. While the manager was out of the room, Kohl flipped through a giant rolodex on his desk, found a card for some guy named Peter, and with a magic marker, wrote his phone number on the palm of his hand.

“Peter,” it turned out, was Peter DiCristofaro, President of the Providence Jewelry Museum in Rhode Island. Kohl’s first phone conversation with DiCristofaro went exactly like this: “Hi. My name’s Hugo, I’ve got some hubs.” Click. Nothing but dial tone from DiCristofaro.

If he couldn’t get DiCristofaro’s attention on the phone, Kohl decided to present himself in person. So he took another trip to Providence, to visit the museum. “At the time, it was at a beautiful atrium in the middle of downtown Providence. There was an exhibition. And people were lined up, out the door, down the street, around the block. These were wealthy people, a little bit older, and they were paying to interact with history and with Peter.” The exhibit, staged to be kinetic, featured  . . .

Continue reading. There’s much more.

Written by Leisureguy

11 March 2021 at 3:36 pm

Google Director Of Engineering: This is how fast the world will change in ten years

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I’ve blogged several times about memes (cultural entities) and how they are subject to the same Darwinian conditions as lifeforms and therefore evolve, and how memetic evolution is millions of times faster than the evolution of lifeforms. Michael Simmons in an interesting article points out that memetic evolution is accelerating as memes lead to the creation of tools that actively support memes and their propagation and thus their evolution — for example, the printing press, radio, television, the Internet. He writes in Medium:

“For the first time since his creation man will be faced with his real, his permanent problem — how to use his freedom from pressing economic cares, how to occupy the leisure, which science and compound interest will have won for him, to live wisely and agreeably and well.”

— John Maynard Keynes (1930)

“Rather than being bored to death, our actual challenge is to avoid anxiety attacks, psychotic breakdowns, heart attacks, and strokes resulting from being accelerated to death.”

— Geoffrey West

Time Is Accelerating Because Of The Red Queen Effect

If a competitor makes an improvement, you must make an equal or greater improvement just to stay neck-and-neck with them. Stay the same and you fall behind.

“Standing still is the fastest way of moving backwards in a rapidly changing world.”

Continue reading. One can observe some of the phenomenon he describes.

Written by Leisureguy

11 March 2021 at 12:51 pm

Posted in Daily life, Evolution, Memes

Stephen Fry comments on the difference between American and British comedy

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Written by Leisureguy

11 March 2021 at 9:28 am

Posted in Daily life, Humor, Video

Darkfall, Valley of Ashes, and another naughty razor made nice

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I began, of course, by applying a small (pea-sized) lump of Grooming Dept Moisturizing Pre-Shave to my face. I noticed that now I can easily pull the right amount from the jar using the tip of my finger. At first it was more difficult, but experience/practice makes physical tasks easier to the point of unthinking habit.

I massaged the pre-shave in thoroughly, adding a pat of water halfway through, then with the Copper Hat’s silvertip badger brush worked up a truly excellent lather from the tub of Darkfall shaving soap.

Declaration Grooming’s Icarus formula is not a vegan formula, and the images on the label provides some clues: bison (tallow), goat (milk), and lamb (tallow). It’s a very good formula (though not so good as the spectacular Milksteak formula from the same maker). The maker’s detailed comments on the formula are worth reading. He notes that it’s a thirsty soap, and I attribute that to the clay in the formula:

Stearic Acid, Water, Castor Oil, Avocado Oil, Vegetable Glycerin, Mango Seed Butter, Potassium Hydroxide, Sodium Hydroxide, Fragrance, Bison Tallow, Lamb Tallow, Colloidal Oatmeal, Goat’s Milk, Lanolin, Bentonite Clay, Tocopheryl Acetate, Hippophae Rhamnoides (Sea Buckthorn) Fruit Extract, Salix Alba L. (White Willow) Bark Extract, Vitis Vinifera (Grape) Seed Extract, Tetrasodium EDTA, Tussah Silk

Darkfall is also available in the Milksteak formulation, which in Canada is carried by Top of the Chain. (It’s out of stock now, but they offer a wait-list feature so you can be notified when they have it again.)

The razor is a vintage French Eros slant that worked well for me for a while, and then I lost the knack and, after one nick too many, banished it to the back row. Since Grooming Dept pre-shave tamed the other two back-row razors, I ventured to bring out this guy, and lo! once again the pre-shave comes through.

I had a wonderfully comfortable shave, with never a nick. The shave was a pleasure and the result superb. I gave the bottle of Valley of Ashes a good shake (it’s an aftershave milk whose ingredients tend to separate — for example, the kaolin clay will settle.

Water, stearic acid, shea butter, castor oil, potassium hydroxide, glycerine, coconut oil, sodium lactate, sodium hydroxide, jojoba oil, aloe powder, liquid aloe, isopropyl myristate, kaolin clay, fragrance

A good shave starts the day right, and today we again have lots of sun, also a help. As I mentioned in an earlier post, I have a shaving-brush article on Sharpologist.

Written by Leisureguy

11 March 2021 at 9:03 am

Posted in Daily life, Shaving

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