Later On

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

Archive for December 22nd, 2020

How Claude Shannon Invented the Future

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David Tse writes in Quanta:

Science seeks the basic laws of nature. Mathematics searches for new theorems to build upon the old. Engineering builds systems to solve human needs. The three disciplines are interdependent but distinct. Very rarely does one individual simultaneously make central contributions to all three — but Claude Shannon was a rare individual.

Despite being the subject of the recent documentary The Bit Player — and someone whose work and research philosophy have inspired my own career — Shannon is not exactly a household name. He never won a Nobel Prize, and he wasn’t a celebrity like Albert Einstein or Richard Feynman, either before or after his death in 2001. But more than 70 years ago, in a single groundbreaking paper, he laid the foundation for the entire communication infrastructure underlying the modern information age.

Shannon was born in Gaylord, Michigan, in 1916, the son of a local businessman and a teacher. After graduating from the University of Michigan with degrees in electrical engineering and mathematics, he wrote a master’s thesis at the Massachusetts Institute of Technology that applied a mathematical discipline called Boolean algebra to the analysis and synthesis of switching circuits. It was a transformative work, turning circuit design from an art into a science, and is now considered to have been the starting point of digital circuit design.

Next, Shannon set his sights on an even bigger target: communication.

Communication is one of the most basic human needs. From smoke signals to carrier pigeons to the telephone to television, humans have always sought methods that would allow them to communicate farther, faster and more reliably. But the engineering of communication systems was always tied to the specific source and physical medium. Shannon instead asked, “Is there a grand unified theory for communication?” In a 1939 letter to his mentor, Vannevar Bush, Shannon outlined some of his initial ideas on “fundamental properties of general systems for the transmission of intelligence.” After working on the problem for a decade, Shannon finally published his masterpiece in 1948: “A Mathematical Theory of Communication.”

The heart of his theory is a simple but very general model of communication: A transmitter encodes information into a signal, which is corrupted by noise and then decoded by the receiver. Despite its simplicity, Shannon’s model incorporates two key insights: isolating the information and noise sources from the communication system to be designed, and modeling both of these sources probabilistically. He imagined the information source generating one of many possible messages to communicate, each of which had a certain probability. The probabilistic noise added further randomness for the receiver to disentangle.

Before Shannon, the problem of communication was primarily viewed as a deterministic signal-reconstruction problem: how to transform a received signal, distorted by the physical medium, to reconstruct the original as accurately as possible. Shannon’s genius lay in his observation that the key to communication is uncertainty. After all, if you knew ahead of time what I would say to you in this column, what would be the point of writing it?

This single observation shifted the communication problem from the physical to the abstract, allowing Shannon to model the uncertainty using probability. This came as a total shock to the communication engineers of the day.

Given that framework of uncertainty and probability, Shannon set out in his landmark paper to systematically determine the fundamental limit of communication. His answer came in three parts. Playing a central role in all three is the concept of an information “bit,” used by Shannon as the basic unit of uncertainty. A portmanteau of “binary digit,” a bit could be either a 1 or a 0, and Shannon’s paper is the first to use the word (though he said the mathematician John Tukey used it in a memo first).

First, Shannon came up with a formula for the minimum number of bits per second to represent the information, a number he called its entropy rate, H. This number quantifies the uncertainty involved in determining which message the source will generate. The lower the entropy rate, the less the uncertainty, and thus the easier it is to compress the message into something shorter. For example, texting at the rate of 100 English letters per minute means sending 26100 possible messages every minute, each represented by a sequence of 100 letters. One could encode all these possibilities into 470 bits, since 2470 ≈ 26100. If the sequences were equally likely, then Shannon’s formula would say that the entropy rate is indeed 470 bits per minute. In reality, some sequences are much more likely than others, and the entropy rate is much lower, allowing for greater compression.

Second, he provided a formula for the maximum number of bits per second that can be reliably communicated in the face of noise, which he called the system’s capacity, C. This is the maximum rate at which the receiver can resolve the message’s uncertainty, effectively making it the speed limit for communication.

Finally, he showed that reliable communication of the information from the source in the face of noise is possible if and only if  . . .

Continue reading.

Written by Leisureguy

22 December 2020 at 4:30 pm

Congress helped with US medical fees — and reminded us of how bad it is

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Paul Waldman writes in the Washington Post:

In the 5,593 pages of the covid-19 relief and spending bill that will soon become law, there are some awful things and some wonderful things. And at least one provision is both.

It’s a provision that protects patients from “surprise medical bills,” just one of many horrors unique to the American health care system. It’s wonderful that the relief bill addresses the problem. It’s awful that it was even necessary.

Here’s how surprise medical bills work. You have an injury or an accident or some other kind of medical crisis, and since you don’t want to get hit with a huge bill, you go to the emergency room of a hospital in your network. Then a few weeks later you get a bill for hundreds, thousands or even tens of thousands of dollars, because unbeknownst to you, someone who treated you wasn’t in your network. Surprise!

Maybe it was the doctor in the ER; it could have been someone who showed up when you were unconscious, so even if you had the presence of mind to ask every person in the room “Are you in my network?” as you were bleeding all over the place, you still wouldn’t have avoided the bill.

As The Post notes, “A study this year by the Kaiser Family Foundation of millions of insurance claims found that nearly 1 in 5 emergency room visits nationwide led to at least one unexpected bill for care outside the patient’s insurance network.”

This worked out great for the health care industry, as long as it didn’t attract too much attention. Insurers could avoid some costs, and as the New York Times reports, “Some private-equity firms have turned this kind of billing into a robust business model, buying emergency room doctor groups and moving the providers out of network so they could bill larger fees.” What an inspiring story of entrepreneurial creativity.

Now the responsibility has been taken off the backs of patients. But Congress excluded ambulance rides, which are usually not in-network and cost hundreds of dollars. And the new rules won’t take effect for another year.

To repeat: It’s great that Congress addressed this problem, even if imperfectly. And it’s absolutely insane that we have a health care system that victimizes us this way in the first place.

You probably know the basic problem: America pays far more than any other country on earth for health care, yet we have tens of millions of people with no insurance at all, and our health outcomes are no better than countries that spend much less. We spend twice as much per capita as the average country in the Organization for Economic Cooperation and Development, yet we have the lowest life expectancy among those advanced countries.

Underneath that broad reality is an orgy of exploitation and victimization in ways large and small, ranging from the bill that’s merely annoying to the one that drives you into bankruptcy.

That the industry has convinced us that we can do no more than tinker around the edges of this system has to count as one of the great propaganda triumphs in history. Wendell Potter, an insurance industry whistleblower, will be happy to explain how he and others spread the lie that the Canadian health care system is a nightmare when it’s superior to ours in almost every way, to convince people that serious reform is impossible and they should be happy with what they have.

Yet if you asked someone from anywhere else in the industrialized world how their country handles surprise medical bills, they’d answer, “What now?” That’s because they don’t have them. Nor do they have “medical debt.” Or “the uninsured.” Or “networks” a provider could be in or out of. It’s just not a thing.

That’s because while there are many different health care models — Britain’s is different from Canada’s, which is different from Germany’s, which is different from Japan’s — all start from the premise that everyone deserves care they can afford. When that requires strong government to make sure prices stay reasonable and patients are protected — even if it means your orthopedist might drive a Volkswagen and not a Porsche — that’s what they use.

Our system, on the other hand, is based on the premise that health care is, at its heart, a business that should continue to generate massive profits, with some regulation that curbs its worst excesses. The result is not only that we have to pay so much for a system with so many holes, but that periodically we learn about some horrific practice like surprise billing, which continues until it gets enough attention that Congress resists industry lobbying and gets rid of it. . .

Continue reading. There’s more.

Written by Leisureguy

22 December 2020 at 4:17 pm

Vegetable melange template

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The way I cook and what I cook changes over time. For example, in May of last year I discontinued adding salt to the foods I cook or eat (and avoid foods high in salt — for example, sauerkraut, pickles, potato chips). And I stopped (in general — occasional exceptions) eating meat, dairy, eggs, and fish — which initially made it difficult for me to think out a meal, but then I found Dr. Greger’s Daily Dozen and have used that as a general guide since.

In this post I’ll describe how I now approach a vegetable dish. I’m not sure what to call it — it’s not a stew, exactly, and it’s always a combination of vegetables. I’ll go with “vegetable melange.” (I also cook a variety of greens together, so I’ll describe later my “greens melange.”) The vegetable melange fits the Daily Dozen category of “Other Vegetables.” (See also an earlier and somewhat different take in this post.)

I now keep on hand some form of cooked beans (beans, lentils, tempeh) and some kind of cooked intact whole grain (kamut most commonly, but also whole rye, hulled barley, red fife wheat — and also occasionally quinoa or amaranth). These take care of the Beans and Grain categories, and when I serve vegetable melange it is with Beans and Grain (and sometime Nuts/Seeds: usually walnuts or pepitas/pumpkin seeds).


Vegetables tend to be bulky (though not so bulky as Greens) until they cook down, so I often use my 6-qt 11.3″-diameter pot (wide diameter helps with cooking), but if I’m going to sauté the vegetables, then I’ll use a large (12″) cast-iron skillet or my 4-qt d3 All-Clad Stainless sauté pan.


I use extra-virgin olive oil (and get a reliable brand), and generally about 1.5 tablespoons. Not much is needed since I include vegetables that will release some liquid during cooking (e.g., mushrooms, tomatoes, summer squash)


I always include garlic. Since the dish is large — I like cook once to get multiple meals — I use a fairly large amount of garlic, generally a head of garlic. I peel the cloves and slice (using a garlic mandoline) or chop them. I do this first in preparing the vegetables so the garlic will have time to rest.

I also include leeks or scallions or (in season) spring onions. I don’t use storage onions all that often since the leaves (of leeks, scallions, and spring onions) have considerable nutritional value and storage onions lack those.

  • Leeks: Use all but the root; the leaves are very nutritious, but rinse the top well after halving the leek lengthwise: dirt tends to collect at the base of the leaves. As a snack, I like to roast short sections of the white part of a leek, and then I save the top (green) part to cook in my next vegetable melange.
  • Scallions: I use these often since they are always available and the generous extent of green enhances the nutritional value. I much prefer thick scallions to those the diameter of knitting needles. I certainly use scallions in salads but mostly in cooking.
  • Spring onions are available in only one season, which I will at some point reveal. They are really excellent, and they come in both white and red varieties. (I always go for a darker vegetable color if there’s a choice: darker pignments in general are a sign of more phytonutrients.) Spring onions have a definite bulb and large, long leaves.
  • Storage onions: These are always available. I prefer red to yellow and yellow to white. White onions are easy to peel but very low in nutritional value (but good dietary fiber). Sweet storage onions (Walla Walla, Vidalia, Maui, Texas Sweet) are good in salads but not so good in cooking. They lack the pungency of regular storage onions because they are grown in soil low in sulfur (and presumably because of their genetics).
  • Shallots: These can be considered a type of storage onion, and I do use them occasionally. “Shallot” is pronounced “sha-LOT” and not “SHALL-ut” (despite what you may hear — and while I’m on the topic, “basil” is “BAZ-ul” and not “BAY-sel”).


I always include mushrooms because (a) I like the taste and mouthfeel, (b) they are a good source of pantothenic acid (B5) and when I was using Cronometer I found that my regular diet was a tad light in that, and (c ) they release their water as they cook which aids in cooking the vegetables. I sometimes use oyster mushrooms but more often domestic white or crimini mushrooms. (When crimini mushrooms grow up, they are called portobello mushrooms.) Depending on my mood, I chop them coarsely or slice them, thickly or thinly.

Root vegetable

I generally will include one or two root vegetables.

  • Daikon radish has a variety of good nutrients, but the one of interest to me is potassium, since Cronometer showed I was running light on that. (Tomato paste is also a good source, and I often use that as well.) One short section, diced, is enough.
  • Beets: Naturally I prefer dark red to golden beets (the darker the color, the more nutrients (in general)), and I just dice them. The juice from raw beets doesn’t stain the way juice from cooked beets does. I rinse them well but don’t peel them, and I follow this rule in general (with some exceptions — e.g., bananas, oranges). One beet is enough.
  • Carrots: Again, I just dice the carrot, and one is enough.
  • Turnip: Same as carrot. Though turnips are not terribly high in food value, I like the taste.
  • Potatoes: Never. Potatoes raise my blood glucose, plus regular potatoes (russet, Yukon gold, white potatoes) seem boring. So far as I’m concerned, they don’t bring much to the party. Sweet potatoes are more interesting (and more nutritious), and I particularly like purple sweet potatoes, which have a wonderful flavor, but there is for me the blood glucose problem.
  • Celeriac/celery root: I actually don’t eat this often, but it’s a good choice and quite tasty. I think I’ll get some.
  • Parsnips: Same problem as potatoes: too great an impact on blood glucose.
  • Turmeric: I like to include turmeric root — generally a couple of pieces about 2″  long that I chop small. And to make the nutrients bioavailable, it’s important to include a fair amount of ground black pepper. I especially don’t peel turmeric; since it is so stainy, I handle it as little as possible.
  • Ginger: Good fresh ginger is a nice addition. I will either chop it fine or slice it on my garlic mandoline.


Peppers are always good, both hot (jalapeño, habanero, Thai red or green, serrano) and mild (Anaheim, poblano, bell peppers (green, red, yellow, or orange), banana peppers, Hungarian peppers). Hot peppers I chop including core and seeds; mild peppers I remove core and seeds. A small can of chipotles in adobo is a nice addition — cut up the chipotles with kitchen scissors — if you like spicy.


I like to include eggplant from time to time, either Japanese or Italian. I dice it in large dice so I can get the taste and mouthfeel. (I do not, of course, even thinking of peeling them.) When I include eggplant, I generally omit the root vegetables, and I also include:

  • Zucchini and/or summer squash: Like eggplant, cut in rather large dice so it will maintain some structure.
  • Tomatoes: Canned tomatoes (generally whole Roma/San Marzano tomatoes, which I cut up with kitchen scissors after adding to the pot; sometimes diced tomatoes) or fresh tomatoes (usually halved cherry tomatoes). I also use sun-dried tomatoes (no oil — I find them at Whole Foods), which I cut up with kitchen scissors.
  • Tomato paste: One small can — good source of potassium, as noted above. And it’s worth noting that the lycopene in tomatoes, unlike the lycopene in watermelon (an excellent source), is not bioavailable until and unless the tomatoes have been cooked. Raw fresh tomatoes (in a salad, for example) are for decoration and taste, not nutrition.
  • Pitted kalamata olives: A good amount. Sometimes I halve them to increase the likelihood of getting an olive taste in each spoonful and to check for pits. Often I use them whole.
  • Mexican oregano: A good amount — 1/4 cup, say — and often also thyme (about 2 teaspoons).
  • Italian parsley: I chop an entire bunch — no point in keeping half a bunch of parsley on hand to rot.
  • Red wine or red vermouth: About 1/4-1/2 cup.
  • Diced lemon: A diced lemon works well in here, at least for me.

As you can see, once eggplant enters the picture, it tends to take over the dish and pushes it toward ratatouille, but still I resist — for example, I might also include some chopped fresh fennel.


Besides summer squash (yellow crookneck or patty pan) and/or zucchini, I might also include diced winter squash: delicata, buttercup (a favorite), or kombucha. I don’t use an entire winter squash, but just a quarter or a half. The rest I’ll probably roast, and then I also roast the seeds.


I chop fresh fennel, both fronds and bulb (but not the core), are cook them or use them raw in salads (see: Salad Checklist).


If I’m going to cook leaves, I generally am cooking a batch of Greens, but some leaves are good in cooked vegetables. Italian parsley I’ve already mentioned, but I might also use one or two baby bok choy or baby Shanghai bok choy, or a section of red cabbage (depending on the size of the head, one-eighth or one-quarter), chopped. Cilantro I would add at the end, not during cooking. Fresh tarragon has a wonderful flavor.


I don’t often see, but it is excellent to add: peel and dice. It’s also good raw, slivered for salad.

Flavor boosters

Last, I always include flavor enhancers.

  • Umami booster: Tamari or soy sauce or Worcestershire sauce or fish sauce (preferably Red Boat)
  • Added acid: Acid brightens the taste. I use a good splash of vinegar (apple cider or red wine or sherry or rice vinegar) and/or lemon pulp. Sometimes I dice a whole lemon (cut off and discard ends, cut lemon into slabs and dice them), which works best if the peel is thin. Meyer lemons are excellent for this.
  • Herbs/spices: Crushed red pepper, Mexican oregano, thyme, rosemary, marjoram, herbes de Provence, paprika, and so on — whatever catches your eye and sounds good.
  • Liquid smoke: If I’m in the mood. Just a littlle is plenty. Wright’s is a good brand. Colgin includes additives that don’t appeal to me.
  • Miso: A good big spoonful of miso (red, white, brown…) adds a nice flavor.

This is one of those posts to which I’m sure I’ll return and augment as additional things occur to me. But I think there’s enough here to get you started.

Written by Leisureguy

22 December 2020 at 12:18 pm

Marvelous razor, marvelous soap, marvelous shave

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And the brush (Phoenix Artisan’s Green Ray) is alo very nice. Stubble Trubble is, alas, no more, and so this tub of Up & Adam, with a vanilla-espresso fragrance, is the last I’ll have. I treasure it: excellent lather and divine fragrance.[

iKon’s open-comb razor, sold now with a B1 coating, is a remarkably good razor: totally comfortable and yet efficiently produces a totally smooth result in three passes: no effort, no danger, no kidding. I love the razor.

A good splash of Phoenix Artisan’s excellent Spring-Heeled Jack coffee-fragrance aftershave (which drys down to a kind of musky wood fragrance) and the (very sunny) day begins, with a few vestiges of snow from yesterday’s sullen cold weather.

Written by Leisureguy

22 December 2020 at 9:55 am

Posted in Shaving

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