"Classic" Timekeeping, Part I: Introduction

Following the suggestion and subsequent reminder (nothing like a deadline to get the creative juices flowing) from gg at Skulls in the Stars, I’ve got two “old” papers that I’m going to summarize.

I recommend choosing something pre- World War II, as that was the era of hand-crafted, “in your basement”-style science. There’s a lot to learn not only about the ingenuity of researchers in an era when materials were not readily available, but also about the problems and concerns of scientists of that era, often things we take for granted now!

These are from 1931, fulfilling the pre-WWII criterion, when you still had individuals engaging in research that were self-financed or supported by a patron and much of the equipment was self-manufactured. The science in this case was largely self-funded, and as for the “basement,” well, it’s a pretty fancy basement as you’ll see, as one might suspect of someone who can fund his own science. But classic nonetheless. There’s a bit to do, and I’m going to break it up into more manageable chunks.

The papers in question are from the Monthly Notices of the Royal Astronomical Society, Vol. 91, published in 1931, and are “The Precise Measurement of Time” by Alfred L. Loomis (p. 569-575) and “Time, Analysis of records made on the Loomis chronograph by three Shortt clocks and a crystal oscillator” by Brown, E. W. & Brouwer, D. (p.575-591). (I, know, I know. They sound like tabloid headlines, don’t they?) The first paper describes various apparati used, and the second describes a particular measurement that was of interest to me.

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Richard Feynman and The Connection Machine

Richard Feynman and The Connection Machine

Story of Richard Feynman working at Thinking Machines.

Many a visitor at Thinking Machines was shocked to see that we had a Nobel Laureate soldering circuit boards or painting walls. But what Richard hated, or at least pretended to hate, was being asked to give advice. So why were people always asking him for it? Because even when Richard didn’t understand, he always seemed to understand better than the rest of us. And whatever he understood, he could make others understand as well. Richard made people feel like a child does, when a grown-up first treats him as an adult. He was never afraid of telling the truth, and however foolish your question was, he never made you feel like a fool.

via Daring Fireball

Beulah, Peel Me a Piece of Copy Paper

The surprisingly rich physics of peeling paper

[T]he physics of peeling paper almost exactly mimics the stick-slip movement of tectonic plates, right down to the statistics of the time between “quakes” and the correlations between released energy and aftershock activity.

From the preprint, “Line creep in paper peeling:”

For paper, we use perfectly standard copy paper, with an areal mass or basis weight of 80 g/m2. Industrial paper has two principal directions, called the “Cross” and “Machine” Directions (CD/MD). The deformation characteristics are much more ductile in CD than in MD, but the fracture stress is higher in MD [20]. We tested a number of samples for both directions, with strips of width 30 mm. The weight used for the creep ranges from 380 g to 450 g for CD case and from 450 g to 533 g for MD case.

I’ll never look at copy paper the same way again.

It'll Do, But I Wanted a Frikkin' Laser

An electric fly-swatter, over at Built on Facts

Press the button on the side and swing it at the fly in the air; there’s a spark and a pop, and the fly falls out of the sky like a little brick. No mess, and dementedly entertaining (I’ll admit it). Yeah it’s a little redneck, but effectiveness is effectiveness.

Redneck? Surely you jest. What is needed now is a little empirical testing, a la Colbert’s fun with a spark coil.