Author: Discover Main Feed

Yesterday’s book club raised the question of what first inspires young people to get interested in science. Many Cosmic Variance readers aren’t scientists at all, but a lot of you are. So — what first set you down this road? For purposes of this highly non-scientific investigation, let’s define “scientist” fairly broadly, as someone who has either received a bachelor’s degree in some scientific field, or is currently on the road to doing so (e.g. someone currently in high school or college). Even if you’re not currently a full-time scientist, we’ll count you if you got the degree.

Here’s a poll based on my quick guesses as to what might be the leading causes of nudging people into science.

What first inspired you to study science?
	Parent, relative, or friend.
	Role model outside friends and family.
	Teacher or a particular class.
	Science fair, mathletics, or other scholastic activity.
	Personal hobby or tinkering.
	Science books (non-fiction).
	Science fiction or fantasy literature.
	Movies, TV, radio.
	The internet (for you youngsters).
	Other
Free polls from Pollhost.com

I’d be very interested to hear if I’m leaving out some hugely influential category. And you can vote for more than one thing, if you think you were influenced by multiple sources. Among the many flaws of this kind of poll is that you might not actually remember what first inspired you — maybe it was hearing something on the radio, which made you go check out a book, but you remember the book and not the radio show. So be it; just try your best to be honest.

Fat is normally not a word associated with anorexics, but researchers at the Children’s Hospital Boston suggest that people who suffer from the eating disorder anorexia nervosa have some fat stashed away in a surprising place. They may not have a thick layer of fleshy insulation like people with regular amounts of fat, but anorexics do store fat in their bone marrow–with detrimental results. The findings will be published in the February issue of Journal of Bone and Mineral Research.

In the study, researchers took MRI scans of the knees of 40 girls, half of whom were anorexic and the other half healthy. The average age of these girls was 16. Radiologists who studied the MRIs found that girls with anorexia had very high fat content in their knees and less than half as much healthy red marrow.

The researchers say that at an age when young girls should be developing bone mass, the malnutrition induces the bone marrow to stop yielding cells that aid in building bone, and instead redirects the marrow towards forming fat cells.

Science Daily reports:

One speculation is that it’s the body’s attempt to store energy and preserve warmth. Anorexics often develop hypothermia because of a lack of insulating fat, and are often hospitalized with extremely low body temperatures.

Related Content:
DISCOVER: Autoimmune Anorexia
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Image: iStockphoto

Plenty has changed since the last update of the Diagnostic and Statistical Manual of Mental Disorders (DSM), the operating manual for psychiatrists, was published in 1994. With the new fifth version set for a 2013 release, the task force behind the update released its recommended changes for public comment this week, and comments will likely come in droves.

The proposed changes touch many of the psychiatric issues that get people the most riled up. For example, the four separate diagnoses related to autism — autistic disorder, Asperger’s disorder, childhood disintegrative disorder and pervasive developmental disorder not otherwise specified — would now be referred to as autism spectrum disorders [Los Angeles Times].

That won’t sit well with many people who have Asperger’s, Geraldine Dawson of the advocacy group Autism Speaks tells the Los Angeles Times, because they see their condition as something distinct from the others. People with Asperger’s usually don’t have the cognitive and verbal problems that often come with autism, and they can have savant-like abilities. Some scientists are displeased as well. “By massively pathologizing people under these categories, you tend to put them on an automatic path to medication, even if they are experiencing normal distress,” said Jerome C. Wakefield, a professor of social work and psychiatry at New York University [Washington Post].

Other proposed changes include officially classifying binge eating as disorder—but not obesity. Similarly, there’s a proposal to include “hypersexual disorder,” but neither sex nor Internet use (not you, dear reader) would fall under the new “behavioral addiction” category (though gambling would).

In another significant revision, the new DSM would add a childhood disorder called temper dysregulation disorder with dysphoria, a recommendation that grew out of recent findings that many wildly aggressive, irritable children who have been given a diagnosis of bipolar disorder do not have it. The misdiagnosis led many children to be given powerful antipsychotic drugs, which have serious side effects, including metabolic changes [The New York Times].

Beyond shuffling the definitions of particular conditions, the new version of DSM would slightly alter the diagnostic process from the top, changing the definition of what a personality disorder is. The proposed revision suggests that instead of a pervasive pattern of thinking/emotionality/behaving, a personality disorder reflects “adaptive failure” involving: “Impaired sense of self-identity” or “Failure to develop effective interpersonal functioning” [Psychology Today].

But while that could sound to some ears like quibbling over semantics, the American Psychiatric Association says that the details that go into its bible couldn’t be more important. “It not only determines how mental disorders are diagnosed, it can impact how people see themselves and how we see each other,” said Alan Schatzberg, the association’s president. “It influences how research is conducted as well as what is researched” [Washington Post].

The ASA’s proposals are now up for review and public comment at dsm5.org.

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Science Not Fiction: Is “Big Bang Theory” Bad For Science?

Image: iStockphoto

We live on a wonderful planet with a beautiful Moon. But I sometimes think we got gypped.

The view from Saturn can be sooooo much cooler:

That’s the moon Enceladus passing in front of (what we science-types call “transiting”) Rhea. Enceladus is about 500 km (300 miles) across and Rhea is 3 times bigger. Rhea was about 2.7 million km (1.7 million miles) from Cassini when these shots were taken, and Enceladus a bit closer at 2.3 million km (1.4 million miles). Of course, by a bit closer I mean the same distance our Moon is from the Earth, so there was plenty of room for this mutual event.

Here’s a zoom of the middle frame:

Awesome. Note that these images were taken about one minute apart, so things were hopping. It’s amazing to me that not only can we put a probe around Saturn and get images of its moons, but our math and physics are so freaking accurate we can say, “Hey, you know what? On this date at this time if we turn Cassini that way we’ll see a moon over 2 million kilometers away pass in front of another one nearly 3 million kilometers away.”

Every morning, I have a 50/50 chance of finding my keys. That kinda puts things in perspective.

Love is in the air at NCBI ROFL! Tuesday-Friday this week, we will feature research articles about love in its most physical form (okay, we just mean plain ol’ sex). Enjoy!

“While writing a book on paraphilias, the author made a thorough search of early references to paraphilias in literature, especially the Bible. Surprisingly just one published paper was available in the literature having any discussion on the references of paraphilia in the Bible, and that too was in French. [Bieder J. The polymorphous sexual deviant: a reading of Freud and the Bible. Ann Med Psychol (Paris) 1973;2(2):274-81 [in French]]. For the readers in English language, nothing was available on this interesting topic. The author undertook the task of reading the original Bible and finding out instances of paraphilias mentioned therein. Main paraphilias, abnormal sexual behavior and sexual crimes to which explicit allusions were present in the Holy Bible were adultery, incest, sexual harassment, drug facilitated sexual assault, rape, gang rape, homosexuality, transvestism, voyeurism, bestiality, exhibitionism and necrophilia.”

Image: flickr/charlie cravero

Related content:
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Tsang Cheung Shing is the ceramic artist who created this incredible pottery installation called “Ying Yeung.” The name refers to a Chinese beverage of mixed coffee and tea and also symbolizes the mandarin duck, a metaphor for marriage and love. Just amazing.

Submit your photograph or artwork to the Science of Kissing Gallery and remember to include relevant links.

You would think this bit of news would be coming out of Paris, but Britain has moved a step ahead of the French sartorially by giving their hospital gowns a designer makeover.

No more shifty, drafty paper gowns with bits of anatomy barely covered (there’s another reason why it’s called the I.C.U.); the new gown design aims to retain patients’ modesty and make their hospital stays a little less revealing.

The Design Council of Britain is all set to unveil the new designer gowns made by Ben de Lisi, who has dressed the likes of Kate Winslet. The new gowns are part of a project to improve dignity across the National Health Service.

Ben de Lisi told the BBC comfort was top of his mind when he designed the outfits.

“The old hospital gown was hideous, embarrassing, ill-fitting and probably ill-making too. You are away from home, ill, and in hospital and you have to wear this horrific garment with your arse hanging out. Give me a break. I wanted the new gowns to feel fabulous and aspirational.” De Lisi’s NHS collection, in his signature printed fabric, also includes pajama bottoms, nightwear and slippers.

Unlike many designer clothes, these gowns are a clever mix of functional and practical, says de Lisi–they allow patients to retain their modesty, but also give doctors access to the patient’s body via convenient “entrance points” in the gown. De Lisi stresses that these gowns do not tie in the back, to avoid the aforementioned arse issue.

However, the hospital gowns won’t be introduced to NHS facilities till 2011, which means patients who want hospital haute couture will have to wait a bit.

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Image: Ben de Lisi

Steve Newton of the wonderful National Center for Science Education has written another article promoting science in the Huffington Post, this time about asteroid impacts. And special bonus; he gives your loyal host here a shout-out.

Specifically, he mentions that I have said that the Hale-Bopp comet was larger than what wiped out the dinosaurs. It’s true: the object that created the Chicxulub crater off the coast of the Yucatan was something like 10 km (6 miles) across. The nucleus of Hale-Bopp was roughly 60 km (36 miles) across, meaning it would have had something like 100 times the mass of the dinosaur killer. I have vivid nightmares about asteroid impacts, and one 100x the size of the K-T extinction event is beyond scary.

Right now we lack the capability to stop such a comet impact; Hale-Bopp was discovered less than two years before it sailed by the Earth. It missed us by a huge margin, but had it been aimed at us things would look a lot different around here right now. We may be years away from being able to stop such an event, but as I’ve written before, people like Rusty Schweikart and Dan Durda are seriously considering what we can do, and have even started the B612 Foundation to look into it.

If we’re serious about such threats, were just a few years away from being able to prevent them. Given that statistically big impacts are very rare and only happen every few hundred thousand years or so, I’m rather liking where we stand right now. But that’s if we actually do something now. We need to start working on mitigation techniques, and rockets to carry them. I’m glad the B612 Foundation is working on it.

Related articles: A Pro-science article on HuffPo?

The great French biologist Jacques Monod would have turned 100 today. I am personally fond of him for having said, “What is true for E. coli is true for the elephant,” but he did much more than coin lovely phrases about microbes. His work on how genes switch on and off earned him a Nobel in 1965, and he also gave deep thought to the philosophy of biology, seeing it as the interplay of chance and necessity. Here’s a blog post from Larry Moran with more, and here’s Monod’s 1971 book, Chance and Necessity: An Essay on the Natural Philosophy of Modern Biology

[Thanks to Jim Hu for pointing out this auspicious day!]

Sure, Botox can banish crows feet, smooth those wrinkles, and lift those frown lines, making the client look more youthful–and somewhat expressionless. But the treatment may have effects that are more than skin deep. A new study suggests that by paralyzing the frown muscles that ordinarily are engaged when we feel angry, Botox short-circuits the emotion itself [Newsweek]. 

In the now-common cosmetic treatment, a doctor injects botulinum toxin, sold under the brand name Botox, under the skin. The toxin kicks in, temporarily paralyzing facial muscles, smoothing skin out, and making a person look less wrinkly as a result. That paralysis, however, seems to interfere with a known feedback loop, in which smiling adds to your happiness and frowning multiplies your sadness [LiveScience]. And tamping down a person’s emotions seems to interfere with the ability to read emotions in others. Says study leader David Havas: “Botox [also] induces a kind of mild, temporary cognitive blindness to information in the world, social information about the emotions of other people” [Discovery News].

Havas studied 40 first-time Botox patients before and after their treatments, and both times had them read happy, sad, or angry statements. They then had to push a button, indicating they had understood what emotion the text elicited. The results showed that the patients who had undergone the treatment still understood happy sentences as quickly as they had before; but when it came to angry or sad sentences, they took a little bit more time to comprehend the emotion. Psychologist Arthur Glenberg explained, “Normally, the brain would be sending signals to the periphery to frown, and the extent of the frown would be sent back to the brain. But here, that loop is disrupted, and the intensity of the emotion and of our ability to understand it when embodied in language is disrupted” [Newsweek].

Even though the delay was less than a second, the researchers say that could be long enough to prevent you from picking up subtle emotional cues when you’re talking to a person. As Glenberg said, “If you are slightly slower reacting as I tell you about something that made me really angry, that could signal to me that you did not pick up my message” [Newsweek].

The findings were discussed at the recent meeting of the Society for Personality and Social Psychology, and the study will soon be published in the journal Psychological Science.

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Image: iStockphoto

How much time and energy is wasted as drivers circle around blocks and creep down streets, on the prowl for open parking spots? Burning fuel, they simmer silently in their seats, running late for work and appointments. Thankfully, technology has some solutions to ease the pain of finding parking.

Engineers Marco Gruteser and Wade Trappe of Rutgers University have combined ultrasonic sensors, GPS receivers, and cellular data networks to create a handy and ultra-cheap “parking-spot finder.” Their system distributes the task of finding vacant parking spots to sensors placed on a number of roving vehicles, and then combines the info to make a map of all the available parking in a region. That map could theoretically be accessed through smart phones or dashboard navigation devices.

Technology Review reports:

The engineers devised a prototype of a sensing platform using a $20 ultrasonic sensor that reports the distance to the nearest obstacle and a $100 GPS receiver that notes the corresponding location. They connected both to a lightweight PC with a Wi-Fi card to transmit the data to a central server.

The researchers developed an algorithm that detects parked vehicles based on the ultrasonic sensor’s readings of obstacles. Based on the objects’ width and depth, the readings were further refined to filter away parked bicycles and trees. Then, they integrated this data with maps, to pinpoint the exact location of available parking. The engineers report that they were accurate 95 percent of the time finding slotted parking spaces using this algorithm, and were right 96 percent of the time detecting unslotted parking.

The researchers say that as cars like taxicabs drive around busy areas, they could use the sensors to collect data. The information collected by cabs could be sent to a large central server using cellular networks, and all that info could then be combined to create detailed maps of available spaces. The researchers say this information could be sent back to cars with commercial GPS receivers, if a deal is struck with the navigation companies.

If employed, the Rutgers team’s cheap networking sensors could end up saving cities like San Francisco millions of dollars in “smart parking infrastructure.” Already, the SFpark project in San Francisco allows real time information on parking at metered spaces. The fixed sensors used in that system cost $500 to install and maintain each year–adding up to a tidy $3 million annually. The Rutgers engineers estimate that they could outfit 300 San Francisco cabs for about $200,000, and they say that cab fleet could cover the city’s entire downtown.

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Image: flickr / Extra Ketchup

Utah is only one state over, so when I see a website that tells me a fragment of a comet will hit it on March 1 of this year, I sit up and take notice.

Then I see the flashing text. The multiple colors. The GIANT FONT. The URL: satansrapture.com. Well, still. It can’t be all wrong can it? And then I see the title: “BIBLE CODE PREDICTIONS 2010”.

Oh. I guess it can be all wrong.

OK, Utah, you can rest easy. I’m guessing March 1 will come and go with no comet impact, fragment or otherwise. The Bible code is a long debunked piece of antiscience garbage, basically just people looking at random patterns until they find one that kinda sorta if you squint your eyes and plug up your ears and yell LALALALALALA looks like it might say something sorta correct.

Maybe.

Anyway, I wouldn’t normally link to such low-level and obvious nonsense, but no matter how silly a doomsday claim is, there will always be people out there who take it seriously. So just in case, here you go: there are no scientific predictions that a comet piece will hit Utah, and the Bible Code is total 100% fictitious nonsense.

Unless… hmmm. The Earth is hit by about 100 tons of cosmic debris every night. A lot of that is from comets, small (and I mean small) bits of fluff shed off of previous comet passes. And if you live in Utah and go out March 1, you’re sure to see at least one or two shooting stars…

So maybe that website is right!

Or not. I’m guessing not.

Five years ago, the Cassini spacecraft first detected plumes of water ice emanating from Saturn’s moon Enceladus, making the moon one of the best hopes for finding life somewhere else in the solar system. Astronomers have argued over whether or not those jets come from a subsurface ocean of liquid water, but new findings by Cassini provide evidence that water could indeed be sloshing around beneath the frozen surface of this small moon.

During a 2008 pass through the plumes, the spacecraft found negatively charged water molecules. Back home this short-lived type of ion is produced where water is moving, such as in waterfalls or crashing ocean waves [Scientific American]. Researcher Andrew Coates led the study, which is coming out in the journal Icarus.

Besides the water ions, the team also found negatively charged hydrocarbons—huge ions that could result from Saturn’s magnetic field and the sun’s ultraviolet rays interacting with the atmosphere of Enceladus. Researchers find the combination of ions enticing. “While it’s no surprise that there is water there, these short-lived ions are extra evidence for sub-surface water and where there’s water, carbon and energy, some of the major ingredients for life are present,” said Dr Coates [BBC News]. Previous studies have shown that the Enceladus plumes contain ammonia, which could act as an antifreeze to keep an ocean in liquid state, and others have argued that the plumes are spewing sodium, which would indicate that liquid water had been in contact with rocks that leach salt.

Cassini’s new ion findings make Enceladus look a little more like its big brother, the huge and also hugely interesting Saturnian moon of Titan. In fact, the same plasma spectrometer on board Cassini has been used to confirm the presence of large negative hydrocarbon ions high in the atmosphere of Titan, indicating the presence of an organic mix of chemicals called “tholins” on Titan’s surface [Discovery News]. NASA just extended Cassini’s mission by seven more years, giving it time to learn even more about both of these marvelous moons.

Related Content:
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Image: NASA / Cassini

You might not be a smoker yourself, but hanging around people who are smoking can cause you to inhale noxious cigarette fumes. For years, scientists have cautioned against the ill-effects of such second-hand smoke. Now they’re warning about the dangers of “third-hand smoke”—the chemical traces that cling to a smoker, and that are left behind in a room where someone has been smoking.

A team of researchers at the Lawrence Berkeley National Laboratory found that remnants of a smoke don’t just inertly settle onto surfaces, they can react with a common gas (nitrous acid, which is emitted from gas appliances and vehicles, among other sources) to create carcinogenic compounds known as tobacco-specific nitrosamines (TSNAs) [Scientific American]. The study (pdf) was published in Proceedings of the National Academy of Sciences.

The study suggests that even if a smoker puffs outside, some smoke swirls and settles in clothing and hair and is brought back into the building. With smoking inside, the left-over nicotine residue settles on surfaces like furniture, carpets, and curtains, where it can mix with common gas and turn into the carcinogenic TSNAs. Says study coauthor Hugo Destaillats: “It’s this third-hand smoke residue that is the source of the smells that we all easily perceive in a room or a car where cigarettes have been smoked, as a consequence of such places being coated with cigarette emissions…. And we found that such emissions do give rise to new pollutants when they react with non-cigarette compounds found indoors” [BusinessWeek].

To study how the carcinogenic compounds were created, scientists used samples from the glove compartment of a pick-up truck whose driver smoked in the truck regularly. They also studied a cellulose-containing paper similar to a carpet or drape and let it absorb nicotine from cigarette smoke. They then put this paper in a chamber containing nitrous acid and studied the reaction between nicotine and the nitrous acid. In both the lab and in the truck, the reaction between nicotine and nitrous acid produced substantial amounts of three types of toxic compounds…. All three compounds belonged to a group called nitrosamines, which are known to prompt tumor growth [Discovery News].

The researchers say with so many toxic compounds, young infants could be at a risk as they crawl around on rugs and come into contact with dust. However, they also caution that there needs to be more research into third-hand smoke, and note that the study doesn’t indicate that homes and couches that smell of smoke could potentially cause cancer. To deal with third-hand smoke, researchers recommend avoiding smoking in closed spaces like homes and cars. Also, in enclosed spaces that have seen plenty of puffs over the years, they suggest replacing furniture, carpet and even wallboard to cut down on the amount of TSNA exposure [Scientific American].

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Image: flickr/SuperFantastic

Under the Microscope is a cool website ‘where women and science connect.’ It’s the online component of the Women Writing Science project at The Feminist Press featuring stories from women about science, technology, engineering, and math, and aimed to inspire the next generation of STEM pioneers. Last week I was delighted to chat with one of the hosts, Kristina Necovska. Here’s an excerpt from our Q&A:

UTM: I’m curious whether you’ve found that the public’s ability to distinguish credibility and sound arguments is going out the window?

SK: I’m very concerned. We just saw this hack into e-mails of climate change. Most people made very quick judgments without fully understanding the context of what they were reading. [There is] a survey just released by George Mason University and Yale Center for Climate Change Communication. It’s a dismal report, people more than ever don’t “believe” in climate change.

The big point here is that pseudoscience is on the rise. … It’s dangerous and I’m not sure what it means for the future of science and it’s a big red flag in terms of where we’re going. Science needs a better platform. It’s certainly not about PR in a traditional sense but we have to think about how we’re represented when we’re working against so many other forces that have a certain vested interest. We’re trying to emphasize the best research and [research] is very dynamic. There’s no black and white in the way that the pseudo-scientific [groups] want to represent things.

UTM: Can you give us just a few examples of what ordinary people can do to benefit science literacy?

SK: I think just being engaged and being interested is a big part of it. Looking for sources that you should be able to trust like universities. More and more young scientists are creating their own websites in order to counter the rubbish that’s out there. I’d love to see more young people engaged in their communities — like those that have a [bachelor of science] but are unsure whether they want to go to graduate school — writing op-eds or working with local politicians or schools.

Read the full interview here and stick around to check out other featured stories and interviews at Under The Microscope.

Welcome to this week’s installment of the From Eternity to Here book club. This week we’re tackling two chapters at once: Chapter Four, “Time is Personal,” and Chapter Five, “Time is Flexible.” That’s just because these chapters are relatively short; next time we’ll return to one chapter per week.

Excerpt:

Starting from a single event in Newtonian spacetime, we were able to define a surface of constant time that spread uniquely throughout the universe, splitting the set of all events into the past and the future (plus “simultaneous” events precisely on the surface). In relativity we can’t do that. Instead, the light cone associated with an event divides spacetime into the past of that event (events inside the past light cone), the future of that event (inside the future light cone), the light cone itself, and a bunch of points outside the light cone that are neither in the past nor the future.

It’s that last bit that really gets people. In our reflexively Newtonian way of thinking about the world, we insist that some far away event either happened in the past, the future, or at the same time as some event on our own world line. In relativity, for spacelike separated events (outside one another’s light cones), the answer is “none of the above.” We could choose to draw some surfaces that sliced through spacetime, and label them “surfaces of constant time,” if we really wanted to. That would be taking advantage of the definition of time as a coordinate on spacetime, as discussed in Chapter One. But the result reflects our personal choice, not a real feature of the universe. In relativity, the concept of “simultaneous faraway events” does not make sense.

These two chapters take on a task that is part of the responsibility of any good book on modern cosmology or gravity: explaining Einstein’s theory of relativity. Both special relativity and general relativity, hence two chapters. In retrospect they are pretty short, so an argument could be made that I should have just combined them into a single chapter.

The special challenge of these chapters is precisely that many readers — but not all — will already have read numerous other popular-level expositions of relativity. But you have to do it. Fortunately, my favorite way of talking about relativity is a little bit different from the standard one, and lines up well with the overarching goal of understanding the meaning of “time.” In particular, I try to make the point that the secret to relativity is to think locally — to compare things happening right next to each other in spacetime, not events that are widely separated. You’re allowed to compare separated events, of course, but the answers are necessarily dependent on arbitrary choices of coordinates, and that leads to endless confusion. So you won’t read a lot about “length contraction” or “time dilation,” but you will read a lot about the actual amount of time measured along a trajectory.

Unfortunately, a search for vivid examples of the maxim “freely-falling paths through spacetime experience the longest amount of proper time” led me directly to the most embarrassing mistake in the book. (At least, “most embarrassing mistake so far uncovered.”) Sordid details below the fold!

The mistake is the claim that a clock that sits stationary on a tower will experience less proper time than a clock that orbits the Earth at the same height above ground. That’s wrong: the orbiting clock will measure less time. This appears in the paragraph at the bottom of page 85 and top of 86, and is elevated from “unfortunate” to “a real doozy” by being illustrated in graphic detail by the figure on page 86. Not really any way I can claim it was just a typo.

The subtle issue underlying the mistake is illustrated in this figure, which shows two paths connecting two points on a sphere. Both paths are great circles. The shortest distance between two points on a sphere is a great circle; but it certainly doesn’t follow that any path following a great circle gives us the shortest distance between two points. If you go more than half the way around the sphere, you end up with a pretty long path!

The same kind of thing happens in spacetime. The trajectory of longest proper time between two events will always be a freely-falling trajectory (a geodesic). But not every freely-falling path gives us the longest time, and that’s exactly the case in this example. Given two events at the same position above the Earth, the actual path of longest time is a radial freely-falling orbit. If you want your clock to experience the longest time it can, you throw it straight up in the air to where the gravitational field is weaker (and clocks run more quickly with respect to time measured at infinity) and let it fall back down. A circular orbit actually loses time by staying at the same altitude but zipping around the Earth. I relied on my affection for the general underlying principle, and didn’t bother to sit down and work out the actual numbers in this case, so I never found the mistake. Pretty sure my membership in the general relativists’ guild is going to be permanently revoked for this one.

If you’re still not convinced of the wrongness of my example, here’s an equation, the line element along a circular trajectory in the equatorial plane in the Schwarzschild metric:

On the left we have a small interval (squared) of the proper time τ, what a clock would measure along some path. The first term on the right is the contribution from our motion with respect to t, the time measured at infinity; for any given amount of t, we experience less proper time τ as our height r decreases and the coefficient (1-2GM/r) becomes smaller. The second term on the right is the contribution from our angular motion φ. Taking the square root of the whole thing and integrating along a path gives you the proper time.

We don’t have to go through the entire calculation to convince ourselves that staying stationary on the tower has a longer proper time than the circular orbit does. Both trajectories get the same contribution from the first term on the right side, while the second term is zero for the clock on the tower (it’s not moving, so dφ=0), but it’s negative for the orbit. So the orbit is definitely less time. To be corrected in the next printing.

The deep point, of course, remains true: the time measured by clocks in general relativity depends on their path through spacetime, and the way to maximize that time is to take a freely-falling path. Just not that one.

Whether your fear is panicked, like in a life-or-death situation, or deliberative, like a decision about whether to take a big risk on game show, it all comes back to the amygdala. And a new study of patients with lesions on the amygdala, reported by Caltech scientists in the Proceedings of the National Academy of Sciences, suggests that damage to our brain’s fear center might turn people into reckless gamblers.

The researchers found two women with Urbach-Wiethe disease, which results in damage to the almond-shaped amygdala. Benedetto De Martinoa and his team paired those two with 12 people with undamaged brains, and presented everyone with a series of gambling tests. The study found that healthy volunteers would only opt to gamble if the potential gains were one and a half to two times the size of the potential losses [BBC News]. The women with Urbach-Wiethe, however, would keep rolling the dice as the odds got worse, and in some cases would even play if the potential loss was greater than the potential gain.

Two, of course, is a pretty small sample size. But that problem is unavoidable, the researchers say. They noted this kind of study usually involves only a few people as it is not possible or ethical to deliberately damage a person’s brain to see what happens [Reuters]. So Urbach-Wiethe patients are particularly valuable to science, showing how damage to one particular area of the brain can change a person’s behavior.

The PNAS findings also back up what some of the same researchers have documented in previous studies, that the amygdala might be responsible not only for more primal fears, but also for social fears and inhibitions. Last year study coauthor Ralph Adolphs led a separate study of a patient with amygdala damage and found that her understanding of personal space was far different from most people’s (she stood much closer during conversation), and she struggled to pick up signs of fear or aggression in other people. Says Adolphs of the newer work: “A fully functioning amygdala appears to make us more cautious. We already know that the amygdala is involved in processing fear, and it also appears to make us ‘afraid’ to risk losing money” [Reuters].

Related Content:
80beats: An Acidic Brain Leads to Panic; A Deep Breath Can Fix That
80beats: Jell-O Shots in Adolescence Lead to Gambling Later in Life
DISCOVER: Conquering Your Fears, One Synapse at a Time
DISCOVER: Emotions and the Brain: Fear

Image: flickr / Morberg

Oh, I have a very cool anaglyph (red-green 3D images) for you! Stuart Atkinson from the Cumbrian Sky blog has created some fantastic anaglyphs of images from the Mars rover Opportunity as it investigates Concepcion crater. Here are some blocks that look like ejecta from the impact itself:

[Click to embiggen.]

These are beautiful! They almost look sedimentary, which at least makes some sense given that the region Opportunity is roving, Meridiani Planum, was once under water. Closeups of those rocks show they have the famous “blueberries”, concretions of jarosite formed by mineral-laden water.

Stuart has lots more pictures he’s fiddled with, too, and it’s well worth your looking around his site. You should also read Emily Lakdawalla’s great description of Concepcion, talking about how we know it’s a fresh crater about 1000 years old. It’s a fascinating read.

I haven’t read all the new material yet that my good friends at DeSmogBlog are producing. But I have long been suspicious of the attacks on leading climate researchers, like the recently vindicated Michael Mann, because they are so obviously diversionary, and yet also so obviously strategic.

There is no doubt that those attacks have been mounting; I believe a new and full scale “war on science” is afoot in the climate arena, something I hope to say more about shortly.

But in the meantime, it appears that following ClimateGate and GlacierGate, we are once again getting some revelations taking on the other side. Maybe this means the pendulum will shift, and good science can move back off the ropes, where it has been for too long. We’ll see. I’ll be watching closely.

Love is in the air at NCBI ROFL! Tuesday-Friday this week, we will feature research articles about love in its most physical form (okay, we just mean plain ol’ sex). Enjoy!

Degrading and non-degrading sex in popular music: a content analysis.

“OBJECTIVES: Those exposed to more degrading sexual references in popular music are more likely to initiate intercourse at a younger age. The purpose of this study was to perform a content analysis of contemporary popular music with particular attention paid to the prevalence of degrading and non-degrading sexual references. We also aimed to determine if sexual references of each subtype were associated with other song characteristics and/or content. METHODS: We used Billboard magazine to identify the top popular songs in 2005. Two independent coders each analyzed all of these songs (n = 279) for degrading and non-degrading sexual references… … RESULTIS: Of the 279 songs identified, 103 (36.9%) contained references to sexual activity. Songs with references to degrading sex were more common than songs with references to non-degrading sex (67 [65.0%] vs. 36 [35.0%], p < 0.001). Songs with degrading sex were most commonly Rap (64.2%), whereas songs with non-degrading sex were most likely Country (44.5%) or Rhythm & Blues/Hip-Hop (27.8%). Compared with songs that had no mention of sexual activity, songs with degrading sex were more likely to contain references to substance use, violence, and weapon carrying. Songs with non-degrading sex were no more likely to mention these other risk behaviors.”

Photo: Wikimedia/Nicholas Ballasy

Related content:
Discoblog: NCBI ROFL: Opera makes me want to kill myself.
Discoblog: NCBI ROFL: Want your rat to get it on while high on ecstasy? Play loud music.
Discoblog: NCBI ROFL: Flatufonia–or the musical anus