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October 2012 Archives

Earthquake Prediction: On Solid Ground?

Yesterday's news that the Italian courts sent seven seismologists to jail was stunning. It is a complete failure of their court system.

Beyond the idiocy of blaming those who try to help, the expectation that seismologists can predict earthquakes like tomorrow's weather is lunacy. Given how spotty weather prediction is, that is a statement!

How good are we at predicting earthquakes? Further, how much do we even understand about the processes that make the ground shift under us?

The record says it all as far as our ability to prognosticate goes. We didn't see the Indian Ocean earthquake of 2004 and its ensuing tsunami coming. We didn't predict the massive offshore Japanese earthquake of last year or the Chilean one the year before. Seismologists are terrible at predicting earthquakes. Leading earthquake researchers are not shy to admit that accurate forecasting is currently almost impossible.

We know where earthquakes are likely to strike, and we know how to measure them as they happen and study them later. Why then do we find it so difficult to predict these events?

Earthquake epicenters are usually 20 miles below the surface, severely limiting our ability to observe precursor conditions. Twenty miles of solid rock is further than we have ever drilled down, and it is opaque to most measurements. An analogy would be like trying to predict weather without being able to see satellite images of clouds. You would have to predict the weather solely based on people looking up at the bottoms of the clouds above.

Much like weather, the motion of the earth's interior is also far too complicated to ever fully predict well. Asking whether a quake is likely to strike on a specific day in six months is like asking whether it will be raining on a specific day in six months.

Even our basic understanding of the earth's crust and the rocky layers just beneath it (called the lithosphere) is very recent. Your parents (or grandparents for younger readers) likely weren't taught this theory (called "plate tectonics") when they were in school.

Until roughly 60 years ago, nearly everyone believed that the earth's surface was basically immobile. However, geological observations in the first half of the 20th century revealed that plates (pieces of crust -- i.e., enormous sheets of rock -- that span continents) slide around, on and under the earth's surface. 
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In the following years seafloor spreading was also found, giving evidence of a method for creation, or upwelling, of new surface. If surface is being created, but the size of the earth stays the same, it follows that surface must also be destroyed, or pushed back under. Around the same time as seafloor spreading began to be observed, subduction, or pushing of surface back down into the interior of the earth was also discovered.

Faults are the places where crust is forced back down into the earth. One type, called transform faults, are places where pieces of crust crash together and force each other up to form mountains, or simply grate together as they shift about to relieve pressure. Another type, called subduction zones, are where one plate slides underneath another. (These can cause enormous mega-quakes, and one is located off the coast of the Pacific Northwest.)

In short, nearly all earthquakes are caused by plates crashing together, scraping each other, being pushed skyward or pressed down into the earth's interior.

Thus, seismology is a relatively young field, hindered by the difficulty in performing direct observations and measurements. An incredibly complex, mostly hidden chain of events far underground obscures the world beneath. All of these factors cause seismologists to have a hard time understanding and predicting quakes. 

But, there are larger issues at stake in the Italian trial.

More troubling than the misunderstanding of scientific capability demonstrated by the Italian verdict is the trial of science. Scientists can only offer their very best hypotheses, and for a field such as seismology, there are literally no guarantees. The idea of criminal and financial liabilty for best guesses is ludicrous. 

What's next, putting the weatherman in prison for not predicting a tornado?

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October 2012 Archives

Parasites, Both Real and Imagined

Many parasite tales have... wormed their way into our hearts. But, are these stories true? Is there really a parasite that swims up your urethra? Can intestinal parasites cure allergies and asthma?  Are strange parasitic infections prevalent in our everyday lives?

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Loa Loa parasite (Stanford)

Treating diseases with parasites

Treating several human illnesses (Crohn's disease, allergies, colitis, asthma and more) with helminths (parasitic worms) is a growing medical research area. So-called helmenthic treatments are a topic of legitimate medical research. The idea behind this is that part of the body's immune response evolved to fight certain parasites, such as worms. But since these parasites are less common in our daily environment, the immune response may behave irregularly, such as by attacking benign substances like pollen. Perhaps reintroducing such parasites in small quantities may help prevent this abnormal immune response.

Parasites in Sensitive Places

Anecdotes about the candiru fish have been around for years. Allegedly, as people are swimming (and urinating) in a river, a tiny needle-like fish darts through the water, up the stream of urine, and forces itself into the urethra. Once inside, it deploys barbs to latch on and cuts into the veins to drink blood. Can you imagine a scarier thought? 

Fortunately, this is perhaps a tall tale. The candiru fish is indeed a barbed, blood-sucking parasite; its target is the veins in the gills of other fish. However there are no medically verifiable reports of the fish becoming lodged in a person's urethra. Still, we aren't off the hook entirely: the nightmarish candiru may lodge itself in other sensitive spots.

Cat Parasites

Do parasites creep into our daily lives in unexpected ways? There is a hilarious myth that Toxoplasma gondii parasites, found in cat feces, can cause infected cat owners to become crazed cat fanatics. That's not true. However, about 1 in 3 people globally may be infected, and the parasite may be linked to personality changes and suicide

Alternative diseases and remedies

What's worse than real parasites? Fake ones.

There is a medically discredited disorder, in which the sufferer believes they are infested with strange fibers or tiny clawing parasites. This disorder, now considered a symptom of mental illness ("a delusional infestation"), is called Morgellons syndrome. 

If you like your cures as alternative as your conditions, a quick Google search reveals that an entire cottage industry of holistic medicine exists for "parasite cleanses." These claim to cure all parasites, a feat impossible with clinical medicine. Take this claim with a mountain of rock salt.

October 2012 Archives

Atomic Clock Wins 2012 Physics Nobel

The Nobel Prize in Physics was just awarded to American physicist David Wineland and French physicist Serge Haroche for work which lead to development of new quantum computers and ultra-precise atomic clocks.

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Atomic clock at NIST (NIST)

What's interesting about atomic clocks?

Measuring distances is something that we have been doing for thousands of years, but precisely measuring time is relatively new. Did you know that the first (sort of) accurate clock wasn't invented until 1656?

Calendars have been around for much longer, but really, do you ever measure your daily appointments in days or, perhaps, milli-seasons? Calendars, as well as sundials -- another early time-system -- are also no good for measuring time between events. A sundial can tell you whether it is 3 o'clock of 4 o'clock, but it can't tell you when 30 seconds have passed, or how long it took you to get to work.

The maker of the first accurate clock was a fascinating and extremely important early enlightenment figure: Christian Huygens (pronunciation). He designed a  pendulum clock. It works because a pendulum always takes the same amount of time to swing back and forth, regardless of how high it swings. (This sounds weird, but it's true.) This clock only lost a few seconds per day, while previous clocks lost a second almost every minute!

Pendulum clocks were the best in the world until the advent of electronic clocks, first built in 1927 at the famous Bell Labs. Quartz clocks work because the crystal structure of quartz crystal is piezoelectric, which means that when you run electricity through it, the crystal itself expands or contracts. This contraction can be linked to a system of gears to drive a clock. Most wristwatches, wall-clocks, alarm clocks, stop watches and kitchen timers use a quartz mechanism.

Quartz clocks vary in accuracy, generally losing between a second per day and a second per week. This is good enough for timing the roast or being at the meeting at 10:30 sharp. Who cares about making something more accurate?

Well, do you like your smartphone and your car GPS? When you set your watch to the "official time", how do you think that's kept accurate? Without the far greater precision of atomic clocks, these things would not work. More precise, futuristic atomic clocks, based on recent advances could have even more amazing applications. They could measure gravity by the change in the speed of time, allowing the detection of lava, metal, or oil beneath the surface of the earth. They might even be able to test the salinity of water, the shape of the sea floor, or the movement of plates beneath the earth that cause earthquakes.

So how do atomic clocks tick?

Because of quantum mechanics, we know that electrons can only exist in certain very particular states around atoms. They can only be in one energy level and place, or another, but NOT between. When an electron is pushed from a lower energy level to a higher energy level, it generally will only stay there for a certain amount of time before it falls down again. It turns out that the electron stays there for an extremely precise amount of time (.000000000108782775708 seconds for a common cesium atom clock). If you kick the electron up, let it fall down, then immediately kick it back up again, it will go up and down 9,192,631,770 times in one second. Each time the electron falls down, it emits light. The clock works by measuring light waves, and counting one second every time that 9,192,631,770 light waves are seen.

A clock like this only loses a second over something like one million years!

These extremely precise clocks are a fundamental part of our present. The work that won the prize actually makes possible a clock many times more accurate than that.

October 2012 Archives

Mad Scientists of the Modern Age: Nikola Tesla

What is the first image that pops into your mind when you hear the phrase "mad scientist"? Quite possibly (unless you chose the "mad chemist" wielding test tubes and Erlenmeyer flasks of frothing liquids) it is an eccentric early-twentieth century man, in a lab full of enormous electrical machinery. Sparks fly, leaping from the equipment around him while he intently fiddles, impervious to the fiery danger. He works all night in a cavernous lab crowned by an electrical tower and lit only by dim bulbs and occasional arcs of electricity. He almost never sleeps. He hopes to build death-rays, create earthquakes, revolutionize the world.

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You've just envisioned Nikola Tesla. Yet, he was not as mad as we picture him.

Before we delve into Tesla's crazier aspects, it is important to pause and recognize how brilliant he was and how important his work is to the quality of life that we enjoy today.

Edison's light bulb is trumpeted as the signal achievement beginning the electrical era. However, it was Tesla who devised most of the alternating current (AC) electrical systems that the world's power grids are modeled upon. He single-handedly patented AC electrical generators, transformers, power lines, and motors. The electrical system formed by these devices proved so much superior to Edison's direct current (DC) electrical system that it was adopted universally across the globe. This was despite Edison's public relations battle, which included the invention of the electric chair and the public electrocution of animals.

Tesla was in many ways the opposite of Thomas Edison. Edison was never known as a brilliant man, but as a methodical, determined one. "Genius is 99 percent perspiration and one percent inspiration," he once said. Tesla was a nearly unparalleled genius, but lacked the business intuition and common sense of Edison. Edison died rich and one of most famous men in the world, while Tesla died penniless and alone, feeding pigeons.

Tesla's legacy includes the first working large-scale hydroelectric power station, and the first remote control demonstration. (A remote control toy boat, but still.) Tesla was also among the first scientists in the world to take X-rays, to design a fluorescent lightbulb, and (probably the first) to discover the ideas of radio transmission and radar. He wirelessly lit lightbulbs several feet away and found experimental hints of the resonant frequencies of the earth's atmosphere, which were not to be theoretically and experimentally validated for another 50 years. He died owning roughly 300 patents.

After years of wildly successful invention, Tesla began to lose his way, making grandiose, eccentric and sometimes completely impossible claims. He fervently spoke of building a "teleforce weapon" capable of melting steel wirelessly from 200 miles away. Upon his death, a box supposedly containing a death ray part was found to contain only a basic piece of old equipment.

Tesla believed that he could create a camera to project a brain's thoughts onto a wall. He built a 187 foot-tall tower to try to wirelessly convey electric power across the planet, using the earth itself as an enormous electrical conductor. He wanted to harness the entire sphere of the Earth as a power line! Upon picking up odd signals at one of his labs, Tesla believed that they could have been sent from Mars by using that planet similarly as a conductor.

Celibate his entire life, Tesla became lonely and slightly paranoid in his elder years. He claimed to keep his ideas inside of his brain to keep them from being stolen. He was suspicious of twentieth century physics, as explained by Einstein and others. OCD traits began to hamper him: he could not tolerate round objects, human hair or touching things that might have germs. He was supposedly obsessed with the number three.

Tesla's reputation has grown through many tall-tales: he allegedly caused an earthquake; it was said that he could fell steel buildings and bridges with a pocket-sized machine; he allegedly transmitted electricity 26 miles without wires. It is disappointing that these stories are almost categorically untrue. However, the simple fact that they exist and, like most myths, do have some far-diminished basis in reality is proof of the man's legend. Wireless electrical energy over seven feet became 26 miles and eventually "free energy" from the vacuum.

An entire conspiracy theory movement has formed around Tesla's "hidden" or "suppressed" inventions and ideas. The United States government also unwittingly contributed to Tesla's legacy of mad genius. Shortly after his death in 1943, the FBI seized all of his belongings.

Nikola Tesla never created free energy from thin air. He neither created earthquakes nor built a death ray. He did however, make enormous contributions to the world, leaving us with a fascinating historical character, and some beautiful lightning machines.

(Image: Public Domain)

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