Category Archives: History

Going Retro

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Retro Science – Part 1
Mostly about Matthew Fontaine Maury, the first superintendent of the US Naval Observatory.

Maury embarked in crowdsourcing data in 1842 when, as a lieutenant, he was placed in charge of the Depot of Charts and Instruments of the Navy Department. Sailors followed a strict routine and were systematic in recording very specific observations around the clock. Ships were mobile weather stations, accumulating a standardized set of weather variables with the strictest regularity at 15 minute intervals. As much as sailors emphasized these routines, once a voyage was completed, the logs were practically viewed as rubbish.

But when Maury saw the Navy’s stockpile of old ships logs, he quickly realized the collective information could improve navigation. Maury developed a method to systematically extract key information from each log book.

That Shifty Hydrogen Atom

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Landmarks—Lamb Shift Verifies New Quantum Concept

In the second quarter of the 20th century, quantum theory faced some serious challenges, including unexplained details of atomic spectra and difficulties calculating basic properties of charged particles. In 1947 Willis Lamb and Robert Retherford of Columbia University discovered an unexpected detail in the hydrogen spectrum, later called the Lamb shift, that became an essential clue in solving both problems. The measurement agreed with new calculations and was the first indication that the theoretical approach called renormalization could resolve the mathematical infinities that had threatened to derail the progress of quantum mechanics.

Can't Wait for "Dawn of the Flick II"

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Dawn of the Flick: The Doctors, Physicists, and Mathematicians Who Made the Movies

Today, we know that persistence of vision does not work like the progenitors of film thought it did (the retina does not retain images like Dr. Paris and others theorized), and many movies are filmed in 3-D and displayed on screens that are sometimes five stories tall. But as the technology of moving images has progressed and the group experience of attending a film has gotten increasingly sophisticated, a parallel trend has emerged, namely, to permit anyone to watch anything, anywhere, on a tiny cell phone. Curiously, this medium that was once limited to the single viewer appears to be circling back to that one-at-a-time format. The irony is not lost on Balzer. “It’s a very interesting loop,” he says, pun intended.

A Zero-Sum Game

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Causes of death: 1900 and 2010

Interesting chart; one can see where we’ve made significant progress in reducing diseases like tuberculosis and making the world safer so that accidents account for fewer deaths per unit population. Fewer deaths implies progress. But an increase is not so clear.

We’re doing great on kidneys, but hearts not so much.

As they might say up in New England, you can’t get there from here. Death is a zero-sum game; sorry if this comes as a surprise, but everybody dies. So if you are going to drastically reduce the number of deaths by one method, then those people will eventually die via another. If you eliminate childhood diseases then average lifespans will increase and those spared will die of something else. I can recall a comment in a medicine-related blog post recently, wherein the commenter claimed that something is wrong with the system because the instances of cancer were increasing, as this chart shows. But given some probability of getting cancer as an adult, you expect that increase: if your chance is 25%, then (roughly speaking) every four childhood deaths prevented should give you an additional adult cancer death. Similarly for heart-related deaths. The chart also doesn’t tell you at what age the deaths occurred (though the decrease in rate implies that death is occurring later, on average). So a heart attack that killed a person at 50 in 1900 might translate into avoiding or surviving that attack in modern times, and finally succumbing to heart disease at 70 or 80. That would not be a lack of progress. You simply can’t glean the necessary details from the graph.

Let There Be Light

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Light And ‘The Illusion Of Knowledge’

Often, the familiar hides the deepest mysteries. This is certainly the case with light, one of the take-it-for-granted physical phenomena that surrounds us in everyday life. We wake up to it, we turn it on and off, rarely thinking of what it really is. A good thing, for even the greatest physicists pause before talking about the nature of light.

I Love it When a Plan Comes Together

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Ancient text gives clue to mysterious radiation spike

An eerie “red crucifix” seen in Britain’s evening sky in ad 774 may be a previously unrecognized supernova explosion — and could explain a mysterious spike in carbon-14 levels in that year’s growth rings in Japanese cedar trees. The link is suggested today in a Nature Correspondence by a US undergraduate student with a broad interdisciplinary background and a curious mind.

I'm Also A Drachma Short

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June 19, 240 B.C.: The Earth Is Round, and It’s This Big

Eratosthenes knew that at noon on the day of the summer solstice, the sun was observed to be directly overhead at Syene (modern-day Aswan): You could see it from the bottom of a deep well, and a sundial cast no shadow. Yet, to the north at Alexandria, a sundial cast a shadow even at the solstice midday, because the sun was not directly overhead there. Therefore, the Earth must be round — already conventionally believed by the astronomers of his day.

What’s more, if one assumed the sun to be sufficiently far away to be casting parallel rays at Syene and Alexandria, it would be possible to figure out the Earth’s circumference.

Reminiscing About Dialup

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The Mechanics and Meaning of That Ol’ Dial-Up Modem Sound

Of all the noises that my children will not understand, the one that is nearest to my heart is not from a song or a television show or a jingle. It’s the sound of a modem connecting with another modem across the repurposed telephone infrastructure. It was the noise of being part of the beginning of the Internet.
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This is a choreographed sequence that allowed these digital devices to piggyback on an analog telephone network. “A phone line carries only the small range of frequencies in which most human conversation takes place: about 300 to 3,300 hertz,” Glenn Fleishman explained in the Times back in 1998. “The modem works within these limits in creating sound waves to carry data across phone lines.” What you’re hearing is the way 20th century technology tunneled through a 19th century network; what you’re hearing is how a network designed to send the noises made by your muscles as they pushed around air came to transmit anything, or the almost-anything that can be coded in 0s and 1s.