Monday, November 28, 2011

Gliding Along the Alps for Eleven Hours

Did You Wonder How a Plane Stayed Up for 11 Hours With No Engine? an article by James Fallows about the flight in The Atlantic.

Hedy Lamarr - Screen Siren and Inventor

"Any girl can be glamorous. All you have to do is stand still and look stupid."
Hedy Lamarr was a glamorous Hollywood actress and the inventor of frequency hopping, the basic technique used in wireless communication. Hedy’s Folly: The Life and Breakthrough Inventions of Hedy Lamarr, the Most Beautiful Woman in the World is a new book by Richard Rhodes the Pulitzer Prize winning author of The Making of the Atomic Bomb. The new book is reviewed in Slate: The Inventor in Hollywood; in Nature: Technology: Inventing beauty.

Saturday, November 26, 2011


There's a special section on Allergies in Nature magazine this week. That holds special interest for me personally since I'm allergy prone. I've been violently allergic to eggs since I was an infant - for example, I can't have vaccinations cultured with eggs including flu vaccines. When I was 19, before I knew that some vaccinations were cultured in eggs, I received one and then spent a week in the MIT infirmary - I needed two shots every 15 minutes for the first 36 hours just to keep me alive - ouch!
I had asthma as a child, but grew out of it. I developed an allergy to cats and many other furry animals (but not dogs) while in college - I would walk into a room with a cat and in seconds start sneezing and rubbing my eyes. But that's been much less severe since my early forties. I developed hay fever in my mid-thirties which persists but it seems to be getting somewhat less severe. I also seem to have developed allergies to kiwis and avocados, both of which I loved growing up, both of which I unknowingly ate mixed with eggs (kiwi sherbert and guacamole) during my thirties and ever since have experienced strong reactions.

Atophy: Marching with allergies in Nature is written by an individual tormented by a wide array of allergies. The author also suffered from chronic eczema, one annoyance I've been mercifully spared.

Food: Picky eaters discusses food allergies, including the possibility of creating tolerance by ingesting tiny amounts of the allergen and gradually increasing the dosage.

Wednesday, November 23, 2011

How do porcupines make love?

This riddle appears in the 1987 film Black Widow starring Debra Winger and Theresa Russell.
The two main characters are: women; formidable adversaries; and they are stronger and more clever then the men in the story. They use men to further their goals - kindly in one instance, cruelly in another - but they control their own destinies.
Any other good examples of stories - filmed or written - along those lines?

The article How do porcupines make love? from Annals of Improbable Research, reveals the punch line to the joke and then goes on to detail the actual mating behavior of these mammals - your previous ignorance of you may come to cherish.

When I was a little kid, nine or so, I had heard the f-word, realized of course, it was probably something naughty, but didn't yet know the actual definition. I finally asked another kid, who disdainfully outlined the concept. "Oh," I responded, "you mean copulation?"

Wednesday, November 16, 2011

Leonardo's Rule

Leonardo da Vinci observed that
all the branches of a tree at every stage of its height when
put together are equal in thickness to the trunk

There have been various attempts to explain that, involving the tree's vascular system for example. The preprint Leonardo's rule, self-similarity and wind-induced stresses in trees votes for wind resistance. See also Leonardo's Formula Explains Why Trees Don't Splinter at Science Now.

Monday, November 14, 2011

Ultra High Energy Cosmic Rays

Ultra High Energy Cosmic Rays hit the earth's atmosphere with energies millions of times higher than the most powerful man-made particle accelerator (the LHC). When these cosmic rays slam into the atmosphere, they create an air shower of up to billions of secondary particles which can be detected on the ground. They also generate a streak of ultraviolet light bright enough (barely) to be detected on the ground in ideal conditions. There are two amazing detector arrays: the Pierre Auger Observatory in Argentina; and the Telescope Array Project in Utah, which are currently collecting data using vast arrays of detectors. The recent preprint Ultra High Energy Cosmic Rays reviews the latest data gathered by these two observatories. One of the main unresolved questions is the source of these fantastically energetic particles - which particles are produced within our own Milky Way galaxy and which are extragalactic.

Thursday, November 10, 2011

Nonlocal Correlations without Alignment or Calibration

Nonlocal correlations are one of the spookiest things about quantum mechanics. Einstein didn't much care for quantum mechanics, he tried to show that quantum mechanics was inconsistent with his special theory of relativity with the EPR paradox. While thought provoking, the EPR paradox did not end up being viewed as a fatal flaw for quantum mechanics.
Experimental schemes for actually testing quantum nonlocality have required quite a bit of alignment and calibration of different parts of the experiment which might make a skeptic wonder if such experiments really are an ironclad test of nonlocality. The preprint Guaranteed violation of a Bell inequality without aligned reference frames or calibrated devices is a clever test of quantum nonlocality which doesn't require a lot of the alignment and calibration steps used in other approaches.

Einstein and controversy in Weimar Germany

Einstein's theory of general relativity was astonishingly controversial around 1920, even at the level of the general public. Einstein was caught up in the politics and anti-semitism rampant in Germany at the time. See the preprint Reactionaries and Einstein's Fame: "German Scientists for the Preservation of Pure Science," Relativity, and the Bad Nauheim Meeting
Cut with a kitchen knife, Dada through the last Weimar beer belly culture of Germany, 1919/1920 - Hannah Höch

Tuesday, November 08, 2011

Spacecraft Navigation by Pulsar

Currently spacecraft find their position and velocity using radio signals sent back and forth from earth-based antennas. That's quite accurate for the components of position and velocity in the direction of earth, but in other directions the accuracy is not so good. The authors of the preprint Autonomous Spacecraft Navigation Based on Pulsar Timing Information propose using an x-ray telescope onboard the spacecraft to track the signals emitted by pulsars, which rival atomic clocks in accuracy. New models of x-ray telescopes are getting small and accurate enough to find the position and velocity of a spacecraft more accurately than an earth-based system, for interplanetary missions when the spacecraft is more than 1AU from earth.