Category Archives: History

Wear Your Safety Goggles

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Because this story might cause something to get into your eyes

Vietnam War bracelets come full circle

Air Force Capt. James Hivner was 60 miles north of Hanoi on Oct. 5, 1965, when his F-4 fighter was hit. He dropped his bombs onto the ammunition dump he was targeting and ejected from the burning plane.

Hivner was quickly captured and endured nearly eight years of brutality. He was beaten and whipped, starved, and held in near-total isolation. In 1973, he was one of 590 American POWs in Vietnam released as part of the cease-fire agreement that ended the war.

“I was in the hospital recovering when I started getting these little packages,” Hivner said.

Inside each was a bracelet with his name etched on it and a note of thanks.

Through the years, the 79-year-old retired colonel has received scores of bracelets. The most recent came last Memorial Day. He keeps them in a shoebox.

What Quantum Mechanics is (and isn't) Good For

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What Is Quantum Mechanics Good for?

Max Born said that by manipulating this wave function that Schrödinger developed, you could tell the probability of finding the electron at any point in space and time. From that, it turns out that the electron can only have certain discrete energies inside an atom. This had been discovered experimentally; this is the source of the famous line spectrum that atoms exhibit and that accounts for why neon lights are red whereas sodium streetlights have a yellow tinge. It has to do with the line spectra of their respective elements.

But to have an actual understanding of where these discrete energies come from—that electrons and atoms can only have certain energies and no other—is one of the most amazing things about quantum mechanics. It’s as though you are driving a car on a racetrack and you are only allowed to go in multiples of 10 miles per hour. When you take that and you bring many atoms together, all of those energies broaden out into a band of possible energies.

I like the point about how in basic discovery, nobody is thinking about applications down the line — Schrödinger didn’t have the diode laser in mind when he was developing the theory

If you went to Schrödinger in 1926 and said, “Nice equation, Erwin. What’s it good for?” He’s not going to say, “Well, if you want to store music in a compact digital format…”

via

Going Green(wich)

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Oct. 13, 1884: Greenwich Resolves Subprime Meridian Crisis

Britain had first solved the problem of longitude, Britain had the world’s largest navy, and the sun indeed did not set on the far-flung British Empire. Britannia ruled the waves, so there was no need for Britain to waive its rules.

Thus, the conference established that the meridian passing through the Royal Observatory at Greenwich would be the world’s Prime Meridian, and all longitude would be calculated both east and west from it up to 180 degrees. The conference also established Greenwich Mean Time as a standard for astronomy and setting time zones.

A Matter of Perspective

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Mindset List for the Class of 2014

The class of 2014 has never found Korean-made cars unusual on the Interstate and five hundred cable channels, of which they will watch a handful, have always been the norm. Since “digital” has always been in the cultural DNA, they’ve never written in cursive and with cell phones to tell them the time, there is no need for a wrist watch. Dirty Harry (who’s that?) is to them a great Hollywood director. The America they have inherited is one of soaring American trade and budget deficits; Russia has presumably never aimed nukes at the United States and China has always posed an economic threat.

…

– John McEnroe has never played professional tennis.

– Clint Eastwood is better known as a sensitive director than as Dirty Harry.

– They never twisted the coiled handset wire aimlessly around their wrists while chatting on the phone.

– Woody Allen, whose heart has wanted what it wanted, has always been with Soon-Yi Previn.

… gettin’ old …

What's Eating You?

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A Lecture On The Psychology of Animals Swallowed Alive

From 1925

[Darwin] states that big sharks swallow the porcupine. fish, and has frequently found it floating alive and distended in the stomach of a shark. On one occasion a porcupine fish swallowed by a shark had eaten its way out, not only through the coats of the stomach, but through the walls of tlhe body, and thus destroyed its captor.
Darwin asks, Who would ever have imaginied that a little soft fish could have destroyed the great and savage shark? The diodon iniflates itself with air and water, which it expels with some force when it deflates. The jets of water must cause some curious ticklings to a shark with a lively diodoni in its stomach!