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Odd Lots

  • PLAUD recently announced their NotePin, a little AI device that hangs from a string around your neck. (I assume you could clip one to your lapel, which is what I would do.) I wrote about that concept in my SF and my magazine between 1984-1992. I called them "jiminies" after Pinocchio’s little advisor. Nice to see it become real!
  • This is clever as hell: A sizeable chicken coop without a floor that moves to a new grassy spot in the pasture every day and thus gives chickens fresh grass, fresh bugs, and exercise. Some are even solar powered, wow.
  • Here’s yet another reason to go low-carb and especially low-sugar: a study showing that high-sugar diets may inhibit neuron growth in the brain. I’ve been doing low-carb/sugar for 27 years now. I sure hope this study is correct!
  • Wegovy and similar weight-loss drugs may treat alcoholism and opioid addiction. More research needed, obviously, but boy, that would be HUGE if proven.
  • Lazarus 3.6 is now out. Built with FPC 3.2.2. Bugfix release, but why not have the latest?
  • The Moon is getting its own time zone—or at least a system of standard time that would greatly help calculations of lunar missions. It’s made complicated by the fact that gravitational time dilation is involved; i.e., the gravity of the moon is less than Earth’s gravity, which makes a lunar second shorter than an Earth second. Not much, but at the speeds of spacecraft, that tiny difference can really mess up a mission. [Note well: I got this wrong the first time, and corrected the error here. Alex Dillard pointed out my error and provided a long and detailed explanation of the problem in the comments. Definitely read his comment!]
  • Roy Harvey sent me a link to a BBC article about “knocker uppers,” the people who woke people up to go to work during the British industrial revolution by tapping on their windows with a long pole (especially for upper stories) or (egad) with little hammers. I guess the British never knew that “knocked up” meant “got pregnant” out here in the Colonies.
  • From my friend Pete comes a report of a study indicating that high cholesterol isn’t a heart disease risk if you keep your diet low in carbs and sugar. I’ve heard that in a few other places, but this is a real study, and I sure hope it’s true, as I’ve been low carb/sugar now for over 25 years.
  • Charlie Martin recently posted a number of superb astrophotos, including a picture of hurricane Milton from orbit. I can call them superb because astronomy has been a hobby of mine for over sixty years. Don’t miss it.
  • Carol and I did see comet Tsuchinshan-ATLAS from our front yard, but it was a bare smudge by naked eye, and only showed a trace of coma in binoculars. Yes, we live in Phoenix and light pollution can be intense here. That said, I’m pretty sure that comet Hale-Bopp (1997) and Hyakutake (1996) were lots brighter, and Hale-Bopp was visible for a very long time as comet appearances go.

12 Comments

  1. EdH says:

    On Friday Tsuchinshan-ATLAS was an averted vision object here, but a good 5* in 7×50 binoculars, semi out-of-town.

    Forest fire smoke Saturday night, alas, but the apparent view in binoculars has stayed constant: the comet’s absolute magnitude is fading but at the same time it rising higher in the sky each evening and the moon is coming up later.

    Not like one of the mid-90s comets, but quite decent in dark skies.

  2. Alex Dillard says:

    Regarding the time rate difference on the Moon as compared to the time rate on Earth, you got the difference backwards (Earth seconds are longer than Moon seconds, not the other way around) and you overlooked the dominant mechanism (gravitational time dilation).

    While it is true that a small portion of the time rate offset effect is due to relative motion (the “time slows down as you approach the speed of light” situation which falls under special relativity) the vast majority of the time rate difference between the Earth and the Moon is actually due to gravitational time dilation which is described by general relativity. “Gravitational time dilation” is the effect that clocks run slower (time “dilates”, meaning the seconds get longer) in strong gravitational fields than in week gravitational fields. The two effects sort of compete with each other by working in opposite directions but gravitational time dilation typically wins by a lot whenever it is in play. The relative motion effect slows time on the Moon down slightly, but the gravitational time dilation effect slows time on the Earth quite substantially, enough to overcome the time rate shift from relative motion. The Moon is offset from Earth by a couple hundred thousand miles, and Earth’s gravity (really any massive body’s gravity) decays with distance. The Moon’s own gravitational field is also pretty weak. Because the total magnitude of the gravitational field at the Earth is stronger than that at the Moon, clocks run slower on Earth than they do on the Moon, and that would be true even for the hypothetical case where there is no relative motion at all.

    Sometimes you will see/hear it pointed out that the clocks on GPS satellites have to account for relativity to achieve the high location accuracy we currently enjoy. This is true and most of what must be accounted for is gravitational time dilation. Clocks run faster in space even at that relatively low orbital altitude, and again the gravitational effect overwhelms the opposite effect that the motion of the satellites relative to Earth has on time. Gravitational time dilation is so strong that by just hiking up a few thousand feet in altitude and then back down you can readily observe the time rate change with a couple of atomic clocks. Take one clock with you and leave the other one at low altitude, when you return you will see the atomic clock you took with you on your hike will be ahead.

    1. Many thanks for this! As is my policy, I corrected the bullet item but pointed out that I had it wrong the first time, and pointed them to your excellent comment here. I was aware of gravitational time dilation, but thought (incorrectly) that the two effects are about equal.

  3. Spencer Arnold says:

    A british comedian named Dawn French was an exchange student in America and asked the father of the host family to “knock her up” in the morning. Hilarity did not ensue. (from her biography).

    Also an australian surgeon named kellie when living in america asked to nurse her host’s baby (In antipodean terms, “hold her”; in american terms, “breast-feed her”).

    1. Akiva Eisenberg says:

      the difference between nurse and wet-nurse

  4. Rich Rostrom says:

    I guess the British never knew that “knocked up” meant “got pregnant” out here in the Colonies.
    In The Sign of Four, Holmes tells Watson to “Knock old Sherman up”, and fetch Toby (a dog).

    Also an australian surgeon named kellie when living in america asked to nurse her host’s baby (In antipodean terms, “hold her”; in american terms, “breast-feed her”).

    As in “‘Here! you may nurse it a bit, if you like!’ the Duchess said to Alice, flinging the baby at her as she spoke.”

  5. TRX says:

    > high cholesterol

    “Modern medicine” started in France in the 1800s, when doctors and hospital administrators began using statistical methods to apportion limited medical resources to plague victims and wounded soldiers. The idea moved to England, where location data and mapping were used to locate the epicenters of cholera outbreaks, then spread throughout the world.

    Due to the success of those applications, the medical industry is still statistically based. Statistics is a power tool, like a table saw. Like a table saw, it can bite you if you make mistakes with it.

    Medically, statistics has *two* problems:

    A) the tendency view people as “spherical patients of uniform density”

    (you might remember our discussion of salt vs. blood pressure a few years ago – I have extensive data showing no effect at all for me, while you were in the “is affected by” group)

    and B) confusion of cause and effect.

    In the case of cholesterol, the link between cholesterol and heart disease was based on poor data collection and analysis, which was then institutionalized in medical training. Massive amounts of new data are showing that’s not anywhere near as close a correlation as was initially thought.

    1. All very true, except…I did an experiment, and salt had zero effect on my blood pressure. I like salt. (I believe that’s one of my Neanderthal traits) I stopped adding salt to anything for three months. (Hated it!) My blood pressure didn’t go down. I went back to adding as much salt as I usually do. My blood pressure didn’t go up. I’ve since read that sodium affects far fewer individuals than is generally thought. So I just stopped worrying about sodium.

      What did bring my blood pressure down was losing weight. I peaked at 170 back around 1997, and since then have managed to bring it down to (as of this morning) 148. BP is still a little high, but I take only half the meds I was taking fifteen years ago to bring it down to an acceptable level.

      I’ve read those reports on cholesterol as well, and no longer worry about it. What I wish the medical community would accept is the fact that we are not all alike, and there are both individual and racial differences for many factors.

      1. TRX says:

        > I did an experiment, and salt had zero effect on my blood pressure.

        Oops! “Sorry about that, Chief!”

  6. TRX says:

    > Lazarus

    One of these days I need to check Lazarus out again. I never did write anything of consequence in it; too many bits only worked on Windows, which would have been nice if the documentation had mentioned it, and too many of the tool packages were only half-ported from Delphi and didn’t properly work either.

    I understand “work in progress” and have no problem with it. But they wasted too much of my time with poor documentation.

    That was a long time, ago, though. Things might be much better now.

    1. There is better documentation now. Way better documentation. The group has published a 2-volume set called The Lazarus Handbook. They’re hardcovers and have…placeholder ribbons! (Just like all the old missals I had in the Latin Mass era.)

      The hardcover set is expensive, but I’ve found it well worth the money, considering that the software itself is free. A lot more documentation is available, online or in book form. Here’s the best list I know of:

      https://wiki.freepascal.org/Lazarus_Documentation

  7. TRX says:

    I vastly prefer printed documentation to screen-based stuff. Yes, you can run a search over a file, but you still lose the “just past the middle of the book” metadata. And, of course, you have no bookmarks for a file unless you’re going to be further dependent on some sort of viewer program.

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