Thursday, September 25, 2008

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Physicists have made the first “movie” of a microwave pulse transitioning from the quantum-physics world to the classical-physics world। http://louis-j-sheehan.net

Reporting in the Sept. 25 Nature, the researchers say that their method may help in understanding at what point in nature quantum physics ends and classical physics begins. It could also shed light on how to keep information inside future computers that would take advantage of quantum physics.

Quantum objects — generally, anything that’s small enough to be ruled by quantum physics — can exist in multiple forms at the same time. An atom, for example, can be in two places at the same time, as can the crests and troughs of electromagnetic waves, such as in a microwave pulse.

Any disturbance from the outside world can cause a loss of this quantum innocence — loss of coherence, in physics parlance. The state of the object becomes progressively more definite, until the object picks one state, as would be expected from everyday experience. Normally, physicists cannot capture all the information contained in quantum coherence, since a measurement produces an answer that’s just one in a range of possible outcomes.

Serge Haroche of the Ecole Normale Supérieure and the Collège de France in Paris and his collaborators have now observed this transition in a microwave pulse trapped between two mirrors. The researchers probed the pulse by shooting thousands of rubidium atoms across it, one atom at a time. Each atom extracted a small amount of information from the pulse, without destroying its coherence.

The near-perfect mirrors allowed the photons in the microwave pulse to bounce back and forth, establishing a standing wave that lasted several milliseconds. Through the reflections, the pulse, bit by bit, lost coherence, and the position of the peaks and troughs came closer to being definite.

At the same time, the path the pulse follows to lose coherence is also different each time. To obtain the most complete picture of the process, the researchers repeated the measurement thousands of times on identical pulses.

“This is fascinating work,” comments physicist Mikhail Lukin of Harvard University. It is unique, he adds, “in that it allows one to look directly, in real time, into what happens with a quantum state of light as it loses coherence.”

Haroche says that the team is constantly improving the apparatus so it can preserve the coherence of pulses of higher intensities। Higher-intensity pulses tend to behave more like classical than quantum objects. Thus, the researchers hope to learn more about the boundary between the quantum and the classical world. http://louis-j-sheehan.net

Haroche also says that his team might be able to learn how to use the atoms to restore a pulse’s coherence before it is completely lost. This ability could help researchers design quantum data storage for future quantum computers. Such machines would use the multiple states of quantum objects to essentially perform myriad calculations all at once.

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Trying to keep up with the blogs at ScienceBlogs is like trying to dig a hole in water, they have so many. But still I was surprised that I didn’t know about Science Woman. They just posted a very cool link of their blogroll which contains a zillion links to science/tech/engineering/math (STEM) blogs written by women.

It’s pretty good, but I noticed they are missing a few, so I sent them a comment about it (awaiting moderation as I write this). Here are the ones I read (or listen to):

I bet I’ve missed some. If you know of more, send them to Science Woman! And let me know, too, because I have sooo much spare time to read more stuff added to my feed reader. :-)

Tip o’ the lab coat to ScienceGeekGirl.

September 25th, 2008 2:09 PM by Phil Plait in Astronomy, Cool stuff, Science | 1 Comment »

Trans-cosmic flow broadens our horizon

In one of the weirder astronomy press releases I’ve seen in a while, it appears that material literally outside the visible Universe is tugging on material that we can see.


A cluster showing traces of an unseen tug.
Hubble image of the Bullet Cluster, which appears to be getting yanked by material from The Other Side. Click to embiggen.

What does this mean? First off, let’s take a sec and talk about the visible Universe. If you go outside and look around, you don’t see the whole Earth. You only see a small fraction of its surface, because the Earth is a curved ball. The solid planet itself blocks your view. The farthest you can see is out to the horizon, where the curving Earth dips everything else below your view (well, except for tall objects like buildings and ships at sea, but we can ignore them for this analogy).

The Universe is the same way. The fabric of space is expanding, with the cosmos getting bigger every day. This has an odd effect: objects farther away appear to be moving more rapidly away from us. Eventually, an object can be so far away that the space between us is effectively expanding faster than the speed of light! This does’t violate any physical laws, because nothing material is actually moving at transluminal speeds; it’s just that there is more space itself between us and that object all the time.

This effect naturally provides us with a cosmic horizon. Any object "moving away" from us faster than light can’t be seen by us; the photons it emits can’t keep up with the expansion of space. They lose energy and fall away from view (like a slow walker on a fast treadmill… or better yet, an ant walking along a rubber band that is being stretched). So, to us, an object far enough away is invisible, beyond the Universal horizon.

Weird, huh? Yeah, as usual, things get even weirder.

Now imagine a third object, say a cluster of galaxies, that lies between us and the one that is beyond our horizon. To the cluster, the object may still be visible, because it’s closer, and therefore not receding as rapidly. It’s like an island just over the horizon to you as you look seaward from the beach; to you the island is invisible, but to someone a few kilometers out to sea in a yacht the island is still visible.

That cluster can still be affected by the more distant object, pulled by its gravity, for example. To us, farther away, we don’t see that distant object, but to the cluster it’s sitting right there and still, literally, a force with which to be reckoned.

If you want to go away for a moment and take some Tylenol, I understand। I feel a bit headachy myself just writing this. http://louis-j-sheehan.com

The thing is, astronomers now think they’ve detected this force! Clusters of galaxies are filled with extremely hot gas, or plasma, heated by things like the galaxies’ motion in the cluster. As light from objects farther away passes through this gas, it gets affected by it, and we can measure that change. This is called the Sunyaev-Zel’dovich effect, and it’s too weak to measure well in individual clusters, but by looking at literally hundreds of clusters, the effect adds up and can be seen. [Edited to add: the photons that are being affected are not from the matter beyond the horizon, but from the cosmic microwave background, the relic radiation from a very early time in the Universe, but still in our visible Universe. Sorry I wasn’t clear about that in the original post.]

The total force is fairly big, in fact. Clusters seen in the direction of the constellations Centaurus and Vela appear to have an additional 3 million kilometers per hour added to their usual velocity! That means that some very large clump of matter — probably a cluster of galaxy clusters, called a supercluster — lies in that direction, over the horizon to us but very much visible to clusters we can see.

Imagine! It’s a sobering reminder that the Universe itself is literally bigger than we can see, with the majority of it forever beyond our ken.

And if your quota of weird isn’t yet sated, then ponder this: the expansion is accelerating. That means that objects we can see today, so distant they linger on our current horizon, will eventually fall away from view as the accelerating expansion beats out the velocity of the light they emit. They will literally move beyond the horizon and become invisible. In a sense, it’s as if the visible Universe is shrinking, the horizon getting closer to us every day. The physical Universe is getting bigger, but almost paradoxically what we see of it gets smaller. Someday, billions of years from now, only the closest of objects will remain visible.

Everything else will have sailed below the horizon. So we better take a look around while we still can.

[Incidentally, I cover this topic in more detail in my book Death from the Skies!, coming out in October, but already available for pre-order.]

September 25th, 2008 11:09 AM by Phil Plait in Astronomy, Cool stuff, DeathfromtheSkies! | 72 Comments »

People unclear on the concept

I get email. Because my site has been around a while it rises pretty high in Google searches, and that means all kinds of spam gets sent to me. Invalid offers to buy the site, requests for links, and such.

I just got this email, with the subject line "Link Exchange Request with Free Psychic Readings site":

Hi,

I saw your website’s page and felt that you have a wonderful resource which can be of interest to users on my website who are looking for free psychic readings. We will reciprocate you from one of our good theme based site.

My desired link is

[link redacted] Free Psychic Readings: 5Free Minutes @ [website name redacted] Get Live phone love relationship advice with Free Psychic Readings, Free Tarot Card Readings, Astrology Predictions, Numerology Readings and more on [website name redacted]!

I hope you will find my website another good resource to be added into your website.

Kindly revert back with your preferred linking code, hoping for a positive response from you.

Hmmm, a positive response? Well, I can positively say no.

Maybe these folks ought to actually, y’know, read my site first.

September 25th, 2008 8:09 AM by Phil Plait in About this blog, Antiscience, Humor | 24 Comments »

Shorter creationism

Pithy quote on creationism:

… Imagine how foolish you would feel if a thousand car mechanics tell you that you need to change the carburetor in your car and you keep insisting that they don’t know what they are talking about, elitist auto-experts that they are, because carburetors obviously don’t exist!

I am elitist. That is all.

September 24th, 2008 3:09 PM by Phil Plait in Antiscience, Piece of mind, Religion, Science | 83 Comments »

News: Hubble Shuttle launch delayed to October 14

I just received word that the launch of Atlantis to service Hubble has been delayed from October 10 to October 14। The nominal launch time will be 10:19 p.m. Eastern (US) time. The launch was delayed so that NASA could check out all the facilities after Hurricane Ike. http://louis-j-sheehan.com

This also means that the launch of Endeavour has been delayed to November 16.

For more info, check out NASA’s Shuttle pages.

September 24th, 2008 12:09 PM by Phil Plait in NASA | 9 Comments »

The Mentalist: review

Last night was the premier of the TV "The Mentalist", what promised to be a skeptical look at psychics and police work.

Quick summary: it rocked.

More thorough summary:

Simon Baker as The MentalistWell, it did rock. It’s a crime/detective drama, but also has lots of humor. Simon Baker, dreamy Aussie, plays Patrick Jane, a man who used to be a relatively famous stage psychic, and is now a police detective. He has an incredible gift of observation, able to watch people’s behaviors, notice small background items, note things that are said, and put them together rapidly to form a picture of what’s happening around him.

"The Mentalist" is a different kind of crime drama. Baker is very engaging (especially, evidently, for my wife), and he does have a quality about him that makes him fun to watch. His character invokes sympathy right away, even if he is a bit of a pain in the butt. He’s confident, even a little arrogant, but funny and endearing. It’s hard not to compare him to the titular character from "House", though he’s not as grumpy.

I love love love his character. He hates so-called "psychics" — hates them. In one scene, he comes right out and says there are no such things as psychics! When he did that, Mrs BA, The Little Astronomer, and I all threw our arms over our heads, fists pumping the air! W00t!

But to the meat of this: I think a real skeptic is behind this show, someone who knows about the frauds, fakes, and evil people who claim to speak to the dead. Here’s why:

S P O I L E R S B E L O W

In a series of flashbacks, we see Patrick Jane as he was five years before, a stage psychic who uses all the fraudulent tricks to make people think he can speak to the dead. On a TV show, he also brags that he’s helping the police find a serial killer nicknamed Red John (most psychics make claims like these, but you will never, ever find a case that was solved by a psychic, or even aided by one). Jane brags about his abilities, and insults the serial killer, calling him ugly and small.

The Mentalist, with an unhappy icon
Red John’s signature

When Jane comes home that night, there is a note on his bedroom door… from Red John. The killer wasn’t happy about being insulted in the media by Jane, and so has exacted his revenge. The note says that when Jane opens the door to the bedroom, he’ll find his wife and daughter, dead. In an unusual demonstration of restraint by a TV show, the scene ends showing him opening the door, and we don’t see the bodies. Just a lurid smiley face on the wall, drawn in blood, Red John’s signature.

Obviously, this is when Jane dropped the psychic act and became a vigilante against psychics. It’s also where he joins the police force.

During the show, Jane talks to a psychiatrist because he can’t sleep well at night. When asked why not, he makes up a story about a childhood tragedy. We, the viewers, know the real reason: guilt over the death of his family. His own hubris killed them.

Now let me make an aside. The real tragedy of these blood-sucking "psychics" who "talk to the dead" is that they interrupt the grieving process. If you lose someone you love, it’s awful, terrible, and the pain is tremendous. But, over time, you heal. It takes a long time, and of course you never totally get over it, but eventually you can heal, you can move on. "Psychics" stop this process cold.

By making people believe that their loved ones are still around, still issuing pablum-like things ("I’m happy", "I forgive you"), they don’t let the grieving people heal. They are picking at the wound, keeping it open. Sure, people may feel better in the short term, but the healing process is short-circuited, and that’s very unhealthy. And it’s another in a long list of reasons why people who claim to talk to the dead are so truly evil.

And that brings us to the last scene in "The Mentalist". At the end, after solving the case using his amazing observational skills, Jane goes home. We see it’s the same house he lived in when his wife and daughter were killed five years earlier… but it’s totally empty. All the furniture, all the furnishings are gone.

Jane slowly goes up the stairs and into the bedroom. Like the rest of the house, it’s stripped clean. The only thing in it is a bare mattress on the floor. Jane lies down on it, and the camera pans around, showing the bloody smiley face still on the wall.

I was astonished by this. The character of Patrick Jane feels tremendous guilt — as well he should — over the death of his family. Because of this, he punishes himself by staying in the same house, removing all the trappings of a happy life, and by leaving Red John’s mark on the wall.

But remember, he couldn’t tell the doctor why he wasn’t sleeping. He couldn’t admit to being partly responsible for his family’s death. He was a psychic, and he interrupted his own grieving process.

Beautiful. The writing here was intelligent, thoughtful, and because of this irony based on skeptical knowledge of "psychics", right on the mark.

And, in my opinion — as you might guess — nailed how truly loathsome "psychics" are.

This was one of the most skeptical shows I have ever seen on mainstream TV, and I hope they can keep this up. It showed so many tricks, so many insights into how to defraud people that I would LOVE it if more people watched and absorbed this knowledge. My only fear is that, under pressure from TV suits, they somehow let Jane get over his guilt and forgive the "psychics" — after all, his skepticism is in some ways due to his major character flaw, so it’s not a big jump for the writers to do that. So many shows cop out that way; make the skeptics look like jerks, and make the antiscience followers look sympathetic, when in fact that is far, far from the truth. So many "psychics" are the ones who use people, defraud people, and use their emotional vampirism to get rich, rich, rich.

So I can’t say enough good things about "The Mentalist". It was well acted, well written, and the staging and direction were very good. Overall it was engaging, funny, and drew me right in.

But I think the most important part is that it spoke from a true skeptical standpoint. Jane gave many of the arguments I hear from other skeptics about many antiscience topics, and they come from the star of a mainstream show. And to see a skeptic who is portrayed as sympathetic, attractive, and even likable was a breath of fresh air from a medium — heh, medium — that falls all over itself to give the phonies, the frauds, and the fakes far more than their fair share.

I hope "The Mentalist" has a long, skeptical, and critically acclaimed run.

September 24th, 2008 11:09 AM by Phil Plait in Antiscience, Debunking, Piece of mind, Skepticism | 83 Comments »

Space X to try again this week

The private company Space X will try once again to get a Falcon 1 rocket into orbit. This fourth launch attempt could be as early as September 28!


Space X Falcon 1 static engine firing test for Launch #4
The static firing engine test for the Falcon 1.

They just had a "static firing" a test of the engines with the rocket strapped down। Everything looked pretty good, but they detected a minor fault in the second stage liquid oxygen supply. They’ll be replacing a component in that system just to be safe. http://louis-j-sheehan.com

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Friday, September 19, 2008

dizziness

20th U.S. edition of Gray's Anatomy of the Human Body

Thomas Riccio, a lanky 84-year-old, was dozing off in the waiting room. A former crane operator at a steel mill and a World War II veteran, he had been in for a physical six months earlier and everything was fine. His only chronic medical problem was high blood pressure.

When I called his name, he stood up and swayed, almost losing his balance. His wife and I lunged, each grabbing one of his arms.http://louis1j1sheehan1.blogspot.com

“I’m OK, I’m OK,” he insisted. “Just when I get up sometimes, I almost lose my balance, but I haven’t fallen.”

His wife told me it was the fourth time in three months that he’d come to the VA clinic with dizziness. At our regular visits he always said that everything was good. He wasn’t one to complain.

Slowly we made our way down the hall, Mr. Riccio sliding one hand along the wall.

Dizziness is the third most common symptom in primary care, and it’s one that doctors love to hate. That is because each of the three main cate­gories of dizziness—vertigo, disequilibrium, and light-headedness—has its own lengthy list of diagnoses.

Vertigo is an illusory sensation of motion or spinning, often accompanied by nausea. It can be caused by inner-ear problems, mi­graines, or, if accompanied by other symp­toms, a stroke. Disequilibrium—which is particularly common in elderly patients with arthritis or problems with vision, hearing, or balance—is a feeling of unsteadiness while walking unaided across an open space. Light-headedness is the sensation of near fainting, such as one might experience when standing up suddenly after a day of gardening in the hot sun. It most often results from problems in blood flow to the brain caused by anemia, low blood sugar, hyperventilation, dehydration, or cardiac problems.

Which of these three was Mr. Riccio experiencing? I wasn’t the first doctor to consider the question. Mr. Riccio told me he had gone to the emergency room three months earlier, complaining of dizziness and headaches he’d had off and on for several days. Given the patient’s history of high blood pressure, the emergency room doctor suspected a stroke, so he asked for a CT scan of Mr. Riccio’s brain to see if there were any blocked or burst blood vessels. He also requested blood tests for signs of anemia or low blood sugar. The CT scan and the blood work both came back normal. Mr. Riccio was discharged with instructions to take Tylenol, in case he was experiencing a migraine. During the next three weeks, both the headache and the dizziness eased, but then the dizziness returned.

Over the next few months, he saw three more doctors. One ascribed the headache and dizziness to sinusitis. Another thought it could be inflammation of the inner ear. Another believed elevated blood pressure was the cause. Mr. Riccio tried various treatments to no avail.

Now it was my chance to solve the puzzle.

“It comes and goes,” Mr. Riccio told me. “Last night in bed, I thought I was going to pass out. The room suddenly whizzed around. Just for about 10 seconds, but it felt a lot longer.”

Did it happen more if he turned his head to one side or the other?

He thought for a moment. “To the right,” he said. “When I turn my head to the right fast, I get dizzy.”

“When you stood up in the waiting room, you looked pretty dizzy,” I said. “When you stand up fast, do you usually get kind of light-headed, like you’re going to faint?”

He shook his head। http://louis1j1sheehan1.blogspot.com

What happened when he walked across a large open space? Did he feel unsteady? He said that he didn’t.

I asked Mr. Riccio to follow my forefinger with his eyes. A jerking in his eye movements when he tracked my finger could indicate a problem with the balancing system of the inner ear. The other doctors hadn’t noted any rhythmic jerkiness, called nystagmus, but I wanted to double-check. I repeated the test a couple of times. Mr. Riccio’s eye movements were smooth.

Sometimes the information we get from a patient’s history doesn’t match up with the physical, and we have to go with our gut feeling. My gut was telling me that this was vertigo, even without nystagmus. Could it be benign paroxysmal positional vertigo (BPPV)? This is the most common type of positional vertigo, and it occurs most frequently in the elderly. In almost half of all cases, there is no known cause.

There is one leading hypothesis about how it happens. Inside the inner ear are three fluid-filled, semicircular canals that serve as balance sensors. In patients with BPPV, tiny chunks of calcium carbonate crystals, called otoconia, float into the canals. The crystals are normally attached to a membrane in the inner ear, but they can be dislodged, perhaps by head injury or infection or through the normal degeneration of aging.

+++

“You know those little handheld pinball games?” I asked. Mr. Riccio nodded. “The crystals are like the tiny metal balls in one of those games. Once they’re in the wrong spot, it’s hard to get them back. They roll around every time you move your head and unintentionally set off motion sensors. So your brain gets the wrong information about balance. It thinks you’re moving in one direction when you’re really not. So it overcorrects, and you end up with the spinning sensation.”

He leaned forward and pursed his lips.

“Is there another pill to try?” He sounded tired, a little frustrated.

“Something even better.”

In 1983, John Epley, an otolaryngologist in Portland, Oregon, found that a precise series of guided head movements could rid patients of vertigo by directing the disruptive crystals out of the semicircular canals. Initially the local medical community dismissed his finding. To many physicians, any technique based on a maneuver or manipulation smacks of hocus-pocus. But the treatment was backed up by scientific studies, and by 1992 doctors had come to accept it.

The Epley maneuver is now the standard treatment for BPPV. Because it involves manipulating the head and neck into certain positions, in rare instances it is not recommended for patients with unstable heart disease, severe blockage of the carotid arteries, or neck disease. Otherwise the maneuver is safe and quite effective, re­lieving vertigo in 80 percent of patients with BPPV.

It was worth a try.

I asked Mr. Riccio to sit on the exam table again. I explained that we needed to position him so he was lying on his back with his head hanging to one side and gently tilted backward. I warned him that the changes in position would momentarily trigger the dizziness, if my suspicion about the cause of his vertigo was correct.

Standing at his side, I said, “Hold my right forearm,” as I braced my left hand on his back. “Now turn your head to the right and keep it turned as you lie down.” I guided him down until he was flat on his back, his head tilted back over the edge, his right ear pointing at the floor.

“Whoa, there it goes,” he said, opening his eyes wide. “That’s the feeling. That’s the one.” As I moved his head into the different positions, I pictured a little pinball game and imagined I was directing the tiny balls—the crystals—back into their designated holes.

After 30 seconds I turned his head gently so his left ear was pointing down. Then I instructed him to keep his head still and to roll over onto his left shoulder, keeping his head angled down to the exam table. Another 30 seconds.

“Now please sit up without changing the position of your head and tell me if you still feel dizzy.” I helped him up.

“Oh yeah, very dizzy.” He braced himself, clutching the edge of the exam table.

We repeated the whole sequence two more times, and by the last time Mr. Riccio sat up, the dizziness was gone. It might come back, I told him, but it would probably be less intense. I printed a diagram showing how he could do a modified version of the Epley maneuver at home, using a pillow under the shoulders to position his head at the correct angle. If he did this a few times a day until the dizziness was gone for 24 hours, it would probably stay away for a while, and in some cases for good.

Two months later he was back for his regular checkup। We walked briskly from the waiting room to my office. He was beaming. http://louis1j1sheehan1.blogspot.com

“Doctor, can I give you a hug?” he asked. “You cured me!”

Just call me a pinball wizard.

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Tuesday, September 2, 2008

aspm

The brains of people who have had the misfortune of inheriting specific rare mutations in the ASPM gene are only one-third the normal size. That gene is the locus of beneficial alterations that began to accumulate as early as 8 million years ago in populations of now-extinct apes, according to a report in the May Public Library of Science Biology, an online journal.http://louis_j_sheehan.today.com

At least some of those ancient DNA changes led to bigger brains in various ape species long before human ancestors experienced unprecedented brain growth, theorize Vladimir Larionov of the National Cancer Institute in Bethesda, Md., and his colleagues.

The scientists sequenced the ASPM gene in chimps, gorillas, orangutans, and rhesus monkeys. They then compared the gene's nucleotide sequences among these primate species. Comparable data from people were already available.

Segments of the gene displayed systematic nucleotide additions and repetitions consistent with the evolutionary spread of useful mutations, Larionov says. These DNA fingerprints of natural selection appeared most strongly in gorillas and people. Comparisons of DNA sequences across species enabled the researchers to estimate when favorable ASPM-gene mutations began to spread.http://louis_j_sheehan.today.com

This gene is thought to play a key role in the division of cells that later become neurons and may also have a role in certain cancers, Larionov says.

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