Tag Archives: Physics

Faxes From the Far Side

On the 10th of January 1956—about a decade into the Cold War and about a year into the Space Race—the United States Air Force launched the first vehicle in its top secret Genetrix program. The vehicle was a balloon—an enormous, 200-foot-tall, 100-foot-wide helium balloon—the first of hundreds that the US would ultimately launch from sites in Scotland, Norway, Germany, and Turkey. Upon release, each balloon ascended into the stratosphere, where the winter jet stream was perfectly situated to carry it over and across the interior of the USSR. A coffin-sized gondola dangled from the bottom of each balloon, housing a set of downward-facing high-resolution cameras. Whenever an onboard photocell detected that the surface below was illuminated by daylight, these cameras snapped periodic photographs. The Genetrix balloons were some of the original high-altitude spy cameras—precursors to spy planes and satellites.

Whenever a balloon cleared Soviet airspace, the US Air Force sent an encoded radio signal that would detonate a small explosive charge on the gondola’s attachment line. If all went according to plan, a specially equipped C-119 airplane would be loitering in the nearby airspace, ready to snag the parachuting payload of photographic film in mid-air. Once retrieved, the film was sent back to the states to be developed and analyzed.

Launching a Genetrix balloon
Launching a Genetrix balloon

The Genetrix balloons were designed to be practically invisible to radar, using very thin balloon film and a gondola much smaller than a typical aircraft. And this might have worked were it not for the fact that one of the steel rods in the balloon rigging was 91 centimeters long. US Air Force engineers didn’t realize it at the time, but 91 centimeters happened to correspond to one of the frequencies used by Soviet early-warning radar. This caused the otherwise inconsequential rod to resonate and glint like a mirror on Soviet radar screens.

Soviet leaders were understandably annoyed when their military pilots reported back regarding the nature of these radar reflections. US officials replied that these were innocuous weather balloons for the study of cloud formations, a claim which was roundly ridiculed. During the day, there was little the Soviets could do about it apart from political posturing—the balloons cruised at 55,000 feet, which was higher than Soviet weapons could reach. But MiG fighter pilots soon discovered they could shoot the balloons out of the sky at sunrise. The chill of the night robbed the balloons of some of their buoyancy, and they dipped down into weapons range.

The Genetrix program lasted only 27 days. It had originally been planned to continue indefinitely, but president Eisenhower cancelled any further spy balloon launches due to the Soviets’ strenuous diplomatic protests. Of the 500 or so spy balloons that were launched, only about 50 camera gondolas were successfully recovered by the US Air Force. These provided over 10,000 reconnaissance photos of inland Soviet Union and China, including first peeks at nuclear and radar facilities.

The Soviets recovered a number of the gondolas themselves, and engineers began to dissect them, seeking useful information. To their surprise, they found something inside that happened to solve a little problem they had been having with one of their upcoming space missions: temperature-resistant and radiation-hardened photographic film.

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Absolute Zero is 0K

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Near the heart of Scotland lies a large morass known as Dullatur Bog. Water seeps from these moistened acres and coalesces into the headwaters of a river which meanders through the countryside for nearly 22 miles until its terminus in Glasgow. In the late 19th century this river adorned the landscape just outside of the laboratory of Sir William Thompson, renowned scientist and president of the Royal Society. The river must have made an impression on Thompson—when Queen Victoria granted him the title of Baron in 1892, he opted to adopt the river’s name as his own. Sir William Thompson was thenceforth known as Lord Kelvin.

Kelvin’s contributions to science were vast, but he is perhaps best known today for the temperature scale that bears his name. It is so named in honor of his discovery of the coldest possible temperature in our universe. Thompson had played a major role in developing the Laws of Thermodynamics, and in 1848 he used them to extrapolate that the coldest temperature any matter can become, regardless of the substance, is -273.15°C (-459.67°F). We now know this boundary as zero Kelvin.

Once this absolute zero temperature was decisively identified, prominent Victorian scientists commenced multiple independent efforts to build machines to explore this physical frontier. Their equipment was primitive, and the trappings were treacherous, but they pressed on nonetheless, dangers be damned. There was science to be done.

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The Isle of Doctor Seaborg

Glenn T Seaborg c. 1964
Glenn T Seaborg c. 1964

It was the summer of 1936 when Ernest Lawrence, the inventor of the atom-smashing cyclotron, received a visit from Emilio Segrè, a scientific colleague from Italy. Segrè explained that he had come all the way to America to ask a very small favor: He wondered whether Lawrence would part with a few strips of thin metal from an old cyclotron unit. Dr Lawrence was happy to oblige; as far as he was concerned the stuff Segrè sought was mere radioactive trash. He sealed some scraps of the foil in an envelope and mailed it to Segrè’s lab in Sicily. Unbeknownst to Lawrence, Segrè was on a surreptitious scientific errand.

At that time the majority of chemical elements had been isolated and added to the periodic table, yet there was an unsightly hole where an element with 43 protons ought to be. Elements with 42 and 44 protons—42molybdenum and 44ruthenium respectively—had been isolated decades earlier, but element 43 was yet to be seen. Considerable accolades awaited whichever scientist could isolate the elusive element, so chemists worldwide were scanning through tons of ores with their spectroscopes, watching for the anticipated pattern.

Upon receiving Dr Lawrence’s radioactive mail back in Italy, Segrè and his colleague Carlo Perrier subjected the strips of molybdenum foil to a carefully choreographed succession of bunsen burners, salts, chemicals, and acids. The resulting precipitate confirmed their hypothesis: element 42 was the answer. The radiation in Lawrence’s cyclotron had converted a few 42molybdenum atoms into element 43, and one ten-billionth of a gram of the stuff now sat in the bottom of their beaker. They dubbed their plundered discovery “technetium” for the Greek word technetos, meaning “artificial.” It was considered to be the first element made by man rather than nature, and its “short” half-life—anywhere from a few nanoseconds to a few million years depending on the isotope—was the reason there’s negligible naturally-occurring technetium left on modern Earth.

In the years since this discovery scientists have employed increasingly sophisticated apparatuses to bang particles together to create and isolate increasingly heavy never-before-seen elements, an effort which continues even today. Most of the obese nuclei beyond 92uranium are too unstable to stay assembled for more than a moment, to the extent that it makes one wonder why researchers expend such time, effort, and expense to fabricate these fickle fragments of matter. But according to our current understanding of quantum mechanics, if we can pack enough protons and neutrons into these husky nuclei we may encounter something astonishing.

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Better Call Sol

On 10 January 1709, pioneering weather observer William Derham recorded an historic event outside his home near London. He examined his thermometer in the frigid morning air and jotted an entry into his meticulous meteorological log. The prior weeks had been typical for an English winter, but overnight an oppressive cold had lodged itself over the Kingdom. As far as Derham was aware, London had never experienced so few millimeters of mercury as it did that morning: -12º C.

The remarkable cold lingered in Europe for weeks. Lakes, rivers, and the sea froze over, and the soil solidified a meter deep. The cold cracked open trees, crushed the life out of livestock huddling in stables, and made travel a treacherous undertaking. It was the coldest winter in the past 500 years, and one of the coldest moments in a larger global phenomenon known as the Little Ice Age. Likely causes include volcanic activity, oceanic currents, and/or reforestation due to Black-Death-induced population decline. It is nearly certain, however, that it has something to do with the unusually low number of sunspots that appeared at that time, a phenomenon referred to as the Maunder minimum.

We now know that such solar minima correlate quite closely with colder-than-normal temperatures on Earth, but science has yet to ascertain exactly why. Solar maximums, on the other hand, have historically had little noteworthy impact on the Earth apart from extra-splendid auroral displays. But thanks to our modern, electrified, interconnected society these previously innocuous events could cause catastrophic economic and social damage in the coming decades.

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The Mechanical Battery

In a world where everything from our automobiles to our underwear may soon run on electricity, more efficient portable power is a major concern. After a century of stagnation, chemical and ultracapacitor batteries have recently made some strides forward, and more are on the horizon. But the most promising way of storing energy for the future might come from a more unlikely source, and one that far predates any battery: the flywheel.

In principle, a flywheel is nothing more than a wheel on an axle which stores and regulates energy by spinning continuously. The device is one of humanity’s oldest and most familiar technologies: it was in the potter’s wheel six thousand years ago, as a stone tablet with enough mass to rotate smoothly between kicks of a foot pedal; it was an essential component in the great machines that brought on the industrial revolution; and today it’s under the hood of every automobile on the road, performing the same function it has for millennia—now regulating the strokes of pistons rather than the strokes of a potter’s foot.

Ongoing research, however, suggests that humanity has yet to seize the true potential of the flywheel. When spun up to very high speeds, a flywheel becomes a reservoir for a massive amount of kinetic energy, which can be stored or drawn back out at will. It becomes, in effect, an electromechanical battery.

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The Gravity Express

A forty-two minute gravity train route from New York City to Hawaii
A forty-two minute gravity train route from New York City to Hawaii

About four hundred years ago— sometime in the latter half of the 17th century— Isaac Newton received a letter from the brilliant British scientist and inventor Robert Hooke. In this letter, Hooke outlined the mathematics governing how objects might fall if dropped through hypothetical tunnels drilled through the Earth at varying angles. Though it seems that Hooke was mostly interested in the physics of the thought experiment, an improbable yet intriguing idea fell out of the data: a dizzyingly fast transportation system.

Hooke’s calculations showed that if the technology could be developed to bore such holes through the Earth, a vehicle with sufficiently reduced friction could use such a tunnel to travel to another point anywhere on the on Earth within three quarters of an hour, regardless of distance. Even more amazingly, the vehicle would require negligible fuel. The concept is known as the Gravity Train, and though it seems inconceivably difficult to construct, it has received some serious scientific attention and research in the intervening centuries.

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Evolving Universes

Black Hole in M81
Black Hole in M81

To many it seems unlikely that a universe could spring into being from chaos, and achieve a level of organization advanced enough to allow for life—let alone intelligence. After all, if an electron were only twice the size that it is, chemistry as we know it couldn’t exist. If the Strong and Weak nuclear forces were out of proportion, stars mayn’t work. Over the centuries a number of theories have cropped up to try to explain life, the universe, and everything, but almost none propose to explain how it all came together. As with many problems that are too grandiose to grapple, however, sometimes it’s best to start on a smaller scale.

Evolutionists and naturalists have long observed Earth’s “natural selection” where most creatures create offspring with slightly different characteristics than their own. Those with characteristics better suited to the environment will thrive, procreate, and pass on their heritage; whereas offspring less suited will wither, reproduce less, and their traits will fade and vanish.

Theoretical physicist Lee Smolin looked at the simple, functional elegance found in the the theory of natural selection, and thought that maybe such a concept could be applied on a universal scale. Thus the theory of Cosmological Natural Selection was born.

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Baseball and the Physicists

Without a doubt baseball has had more serious study behind it than any other major sport. It’s hard to say why this is, but we don’t see academic studies on the flight trajectories of footballs or the effect of “soft rims” on basketballs but we do see plenty of research on baseball. Scholarly research papers on baseball have titles like, “An Experimental and Finite Element Study of the Relationship amongst the Sweetspot, COP, and Vibration Nodes in Baseball Bats” and “Determining Baseball Bat Performance Using a Conservation Equations Model with Field Test Validation.”

Very rarely do these scientists, mostly physicists, offer practical advice for players to take into the field, but they do come up with some interesting observations. And almost all of them have to do with the baseball-bat “collision sequence.”

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