Rock Stars Of Science Has No Physicist

I know that they can't please everyone when they make something like this. Last time, in 2009, they made people unhappy because their "scientists" consisted of only white men.

However, this year's Rock Stars of Science, the oversight is, to me, more glaring, and at some level, demeaning. None of their scientists are physicists. In fact, there seemed to be an over-emphasis on medicine and medical research! Who do they think made many of the instruments, equipment, and understood the physics of those things, that these medical researchers use?

Oy, I'd better stop before I get riled up even more....

Zz.

Full Body Scans At Airports

Obviously, the biggest news in the traveling world lately is the controversy surrounding the full-body scans at airports around the world. There are people who don't want to go through it, opting instead for a full body pat down (which in itself could be highly intrusive).

Now, there are various reasons why people don't want to have the full body scans, ranging from privacy matters all the way to safety. Physics can't address issues on privacy matters - it is a personal decision and what you are comfortable with. However, physics can certainly address the latter, which is the radiation safety issues. This is where I see many people are getting either the wrong information, or not realizing what they accept to be "safe" and what isn't.

What makes it a bit confusing is that, at least in the US, there are two types of full-body scans. There is one called the X-ray backscattering scan, and the other being the Millimeter-Wave scan. The former uses weak x-ray to do the scan. The TSA has cited studies in which the amount of radiation received during such a scan is equivalent to about 2 minutes of flight time at high altitude. There's some questions about this number, and some even quote it to be as long as 1/2 hour. Regardless of the number, it is still less than what you get with a dental x-ray, and certainly less than what you would get over a typical airplane flight. So one has to consider, just like having a medical x-ray, if this is an acceptable risk, or not. This is a personal judgment, but it should be decided upon a clear understanding of the radiation amount received IN COMPARISON with others that one has already accepted.

Now, the latter uses non-ionizing radiation, typically in the GHz range. So this is safe as far as "radiation" is concerned. Yet, there are those who are not aware of this. See this blogger, for example.

One report from a very credible source (a famous health author whom I know quite well) reveals that TSA officers told her the naked body scanners don't even emit X-rays. "It's a myth," the officer said. "There are no X-rays from those machines."

Really? Then how do they work? Are they MAGIC? Do TSA officers cast a magic Spell of X-Ray Vision on the air travel passengers like some sort of Dungeons & Dragons adventure?

No, it could easily mean that that scanner is the Millimeter-wave imaging scanner, and it is completely accurate that there are no x-rays from the machines. BTW, there is a very nice paper describing the physics of this technique that you should read if you're interested in this:

D.M. Sheen, et al., IEEE Trans. Microwave Theory and Tech. v.49, p.1581 (2001).

I think people need to make an informed decision here, rather than repeating the same irrational decision that's based on rumors and half-truths. If you know the difference between x-ray backscattering and millimeter wave scans, and you also know how much radiation you get when compared to other types of radiation, then go ahead and decide if you want to skip the scan and do a pat down. But don't decide based on confusing the two types of scans, or simply not knowing the level of radiation that you get when compared to other types that you've already accepted as part of your life.

And don't use the safety card to hide behind other issues. If you dislike the scan because you don't want an image of your pseudo-naked self being displayed on a screen somewhere, then argue it on that point, not on concerns about "safety".

Zz.

Resonance - Music from the ATLAS Experiment

Physicists can be a multi-talented bunch. I wouldn't call myself "talented" in cooking, but I've had many people praising what I cook up in my kitchen. Still, it appears that many of the physicists working at the ATLAS detector at the LHC are talented musician. So it is a natural evolution for there to be a musical album released by these folks inspired by what they do. The album is called "RESONANCE".

Released on the ATLAS scientists’ own label, Neutralino Records, which is named after a hypothetical particle predicted by a theory called supersymmetry in particle physics, ‘Resonance’ features 19 artists over two CDs and a DVD.

The album features a wealth of new songs: the highlights include an original blues song about ATLAS from physicist Steven Goldfarb’s Canettes Blues Band: an ode to CERN from the remarkable singer-songwriter-scientist Cat Demetriades, classical piano pieces by head of ATLAS, Italian scientist Fabiola Gianotti, and the wry musings of guitar band TLAs and their song about their perennial bugbear – long meetings. The artists who appear on the album hope their music will attract a new audience to Physics and encourage young people to study a subject that is often wrongly perceived as lacking in fun.

The whole thing looks very impressive. It would be interesting to get to hear the whole thing.


Zz.

The Periodic Table Party

This is a rather hilarious take on our beloved periodic table. All the elements are here attending a party, and it's pretty funny.

Time to party! We've got goodies to eat, music to dance to, the only odd thing is all the guests are chemicals. This is a Periodic Table party. Neon is here, but she's an incredible snob, doesn't like to touch. Hydrogen, with his dewy blue eyes, wants to hook up with anybody. Carbon — well, Carbon is the hottest thing on the dance floor and can handle four partners at once...Go ahead, check it out...(you are, after all, mostly carbon based).

I wonder which element is the nerdy one? :)

Zz.

Remains of Tycho Brahe Exhumed

The remains of scientist/astronomer of Tycho Brahe, who was buried in Prague, was exhumed to investigate the cause of his mysterious death.

It had been long thought he died of a bladder infection. A famous legend said it was a result of his hesitation to break court etiquette during a reception by leaving for a toilet.

But tests conducted in 1996 in Sweden and later in Denmark on samples of his mustache and hair — obtained during a previous 1901 exhumation — indicated unusually high levels of mercury, leading to a theory of mercury poisoning, even possible murder.

Hey, if they can investigate the cause of King Tut's death, they should be able to put in the same resources to investigate this one.

Zz.

Assembling GRETINA

What is "GRETINA", you ask? GRETINA is "....the most sensitive gamma-ray detector ever built for studies of the nucleus..", currently being assembled at Berkeley Lab.



Zz.

The Spookiness of Quantum Mechanics

We have read/heard this many times before, but I guess it doesn't hurt (unless it is another one of those bastardization of quantum mechanics) to hear it again.

NPR has a coverage of some of the weird things in QM. You can read it, or listen to it, at their website. It is another useful information for people who do not have a physics background.

Zz.

US No Longer A "Collosus of Science"

I think most of us who work in science (especially physics) and have seen the slow erosion of  funding in the physical science would not be surprised by this development. A Thomson Reuters survey of scientific output has shown a decline in scientific publication from the US when compared to Europe and Asia-Pacific countries.

The report, released yesterday, notes that the Asia-Pacific region has now overtaken the US in terms of published papers and spending on research. In 2008 the US invested $384bn while Asian countries invested $387bn in total, and while researchers in the US published around 310,000 papers in 2009, over 330,000 were published by scientists in the Asia-Pacific region.

In the physical sciences, the report notes that investment in physics and engineering in the US has "taken a back seat" compared to the biological science at a time when countries in Asia are increasing their spending on research in the physical sciences. "In physics, the trend for the US in terms of world share is distinctly downward," says the report. 

I have no idea if US politicians actually know about this, or even care! The incoming Republican congress does not even mention anything about the important of science, science funding, and education. And science certainly was dismissed by many of the Tea Party candidate, some of which blatantly proclaimed that Evolution is wrong. So would I be blamed if I see the Dark Ages of Science coming to the US?

Zz.

The Physics of High Heels

I, of course, have zero clue on what's involved in wearing high heels, and I don't plan on changing that any time soon. Still, out of curiosity, I read this article because, frankly, it had crossed my mind how many of these women, especially in the entertainment business, not only could walk, but also dance wearing such high heels. Just go to a typical Broadway musical, for example, and see the moves these women could make while in these pumps.

"Many of my physicist colleagues have no trouble understanding quantum mechanics but can't figure out how women can wear high heels," admitted Dr. Laura Grant, a physicist from Liverpool University.

Yet the recipe for safe stilettos seems fairly straightforward: Two parts sacrifice and a dash of solid steel, said Fred Allard, creative director for Nine West, one of the world's largest manufacturers of women's shoes.

Well, even after reading this whole article, I don't think it has made a sufficient argument that such a thing is "stable". Rather, it is more of having the "skill" to be able to wear these things, very much like being able to ride a bicycle. At some point, after you wear it often enough, you learn how to balance in them.

I'd like to hear from women physicists and engineers on what they think of the physics of these high heels.

Zz.

How Cats Drink

Hey, we seem to be getting quite a bit of pet physics lately. First we had the study on the wet-dog shake, which I thought was quite informative and entertaining. Now along comes a study on how cats lap at liquids when they take a drink[1].

Watching in slow motion reveals that cats of all sizes, from tabbies to tigers, have a very elaborate way of drinking. First, they move the tip of their tongue onto the surface of the water to flick the water up so that a little jet of liquid flies into the air. Then, in a flash, they catch the jet in their mouth.

So you can watch the motion of this yourself.


And now, for the dogs.


Zz.

[1] P.M. Reis et al., current published on Science Express.

Rust And Entropy

I've tried to tackle plenty of news reports and documents that purportedly are based on physics, but really are nothing more than either errors, or complete bastardization of things the writer didn't understand. This is another example, but done by Dan Styer and published in Nov. issue of AJP (D. Styer Am. J. Phys. v.78, p.1077 (2010)). In it, he tackles the claim from several sources that rust occurs due to entropy, i.e. the tendency towards an increase in entropy. He cited several sources for having such a "theme".

This particular quote comes from an online source: Cutler J. Cleveland and Robert Kaufmann, “Fundamental principles of energy,” in Encyclopedia of Earth, last updated 29 August 2008 accessed 12 May 2010. But the spirit of this quote can be found in many places., “Entropy tends to make our eyes grow weaker as we age… entropy causes iron and other metals to rust” appears in Louis M. Savary, Teilhard de Chardin: The Divine Milieu Explained (Paulist Press, Mahwah, NJ, 2007), p. 163., “Entropy imposes itself in the form of limitation and in the natural tendency toward confusion and chaos, toward decay and destruction. Entropy is why ice cream melts and people die. It is why cars rust and forests burn. Preponderantly, the second law describes effects that we don't want to see” appears in Gilbert L. Wedekind, Spiritual Entropy (Xulon, Fairfax, VA, 2003), p. 68.

Of course, anyone who has studied chemistry in college can pick up what's wrong with such a claim. As Styer pointed out, rust occurs when two types of elements interact, i.e. iron and oxygen, via the reaction

Now, one can assume that Fe is in a solid form, while oxygen is in a gaseous form. In general, it is clear that a gas will have a higher entropy than a solid. So what is going on here is that we have an initial condition of a solid iron and a gaseous oxygen, and ending up with a solid rust (iron oxide). This final condition should actually have a lower entropy than solid iron plus oxygen gas. So the entropy of this system should have decreased, not increased as claimed in the cited references.

Of course, the whole entry of the universe does not decrease since the process involved a change in entropy of the surrounding that is higher. But as Styer indicated, the iron+oxygen system itself has a decrease in entropy. Proclaiming that rust occurs because of entropy (i.e. Thermo's 2nd Law) is faulty.

Zz.

"Mystery Missile" was "A Plane! A Plane!"

It may not be "The Plane!", but it certainly can be a plane as the most plausible explanation for the mystery missile over Southern California that caused all of these brouhaha.

It looked like a missile launch, he said, because of an optical illusion that made the contrail appear as though it started on the ground and zoomed straight up. In reality, he said, the contrail began on the horizon and ran parallel to the ground.

"It was an unusually clear day," he said. So what looked like a missile launch 35 miles off the coast of Los Angeles was actually the contrail of a jet that stretched 300 miles into the distance, he said. "At the end of the day, you really have to go with the simplest explanation," he added.
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Harvard astronomer Jonathan McDowell told New Scientist that because a helicopter in flight recorded the video of the incident, it employed a visual angle that distorted the arc of the contrail. That effect was compounded, McDowell maintained, by the distinctive lighting of the sky at twilight--and the net result was a bit of an optical illusion.

"What isn't clear to me is whether anyone but this helicopter saw it," McDowell said. "If it's coming over the horizon, straight at you, then it rises quickly above the horizon. You can't tell because it's so far away that it's getting closer to you -- you'd think it was just going vertically up."

There you have it!

Zz.

Saturday Morning Physics

I love, love, LOVE something like this. If you are in Ann Arbor, MI, you are damn lucky!

This news article highlights the "Saturday Morning Physics" held at the University of Michigan.

"It started over in West Hall in a small auditorium and about 50 people came to the first one," said Carol Rabuck. "By the second one, they had to come over here (Dennison Auditorium) and we've been popular ever since."

Brad Orr, chairman of the Physics Department at the University of Michigan, said people enjoy it because it's accessible to the layperson and the speakers try to make technical subjects across a wide variety of science accessible so people can learn from them.

"Really, from Day 1, there have been several hundred people coming," he said. "And whether it's high school students who are coming because their teachers have encouraged them or given them extra credit, college students, we encourage this in our classes ... or parents will come with their kids, or retired folks. It's just a really broad spectrum of the community."

LOVE IT!

This is the type of activities that we sorely need more of. It isn't just the opportunity to learn about physics, but also the accessibility of the public to talk to physicists and ask questions that they either are curious about, or don't understand. I've always applaud such activities, including those coffee-house physics activities, and the likes. The fact that this Saturday morning physics has become wildly popular is clear evidence that if we have such a thing and promote it well, the people will come!

We truly need more of this. Universities in large cities with good physics departments should organize something like this.

Zz.

Physics Brainteaser Posters

It appears that the Institute of Physics has produced "physics brainteaser" posters that are now up in various public transportation in several cities in N. Ireland.

The poster campaign, Transport Yourself with Physics, was all about getting the public to engage with the subject, said Alison Hackett, policy officer with the institute.

The institute, with the support of the Government’s Discover Science and Engineering programme, organised the campaign, which was launched to coincide with Science Week Ireland.

The posters are now visible on buses and trains in Galway, Cork, Limerick and Waterford. In Dublin they are installed along Dart and Arrow train services and on Dublin Bus. About 200 buses in Northern Ireland have posters in place, Ms Hackett said.

If I recall correctly, a similar campaign was also done somewhere in Massachusetts a while back, where physics posters were on buses.

While I certainly like such a thing, I would also like to see posters linking specific discovery or advancement in physics that led to things like the iPhone, MRI, etc.. etc.. i.e. linking physics to things that the public use everyday. Most people do not realize how they use discoveries in physics. Rather than make some general statement about its usefulness, it would be even more fascinating if one could simply show the "chain of events" that led from one thing all the way to its application and device.

Zz.

Mathematics and Physics

I can't say whether I completely agree with the content of this report, but it is certainly interesting to consider.

This news article reports on a lecture given Dartmouth on the interaction between Physics and Mathematics, its common history, and how they are now different but interconnected. The lecturer has an interesting point on when in history the field of physics and mathematics split.

The fields began to divide in the late 1800s, she said, with individuals coming to identify with one of the two fields.

“The big question is, what happened between the early 1800s and late 1800s?” she said. “Why was there a split into mathematics and physics? The answer: Fourier happened.”

Joseph Fourier is best known for his development of the Fourier series, a method of breaking sounds into components. The method explains, for example, why a violin sounds different from a flute, Singer said. But in addition to the Fourier series, Fourier came up with the theory of heat distribution, a model for how heat travels on a thin, metal plate.

“This [theory] lit up a crisis in the scientific world,” Singer said. “And the resolution of this crisis split natural philosophy.”

Natural philosophers had formerly agreed upon the definition of a function as a formula and a formula as a function, according to Singer. But to support his theories, Fourier used functions, but not formulas — contradicting the commonly held notion that the two were interchangeable, she said.

As a result of this unprecedented disagreement, mathematics and physics diverged from one another. Those who agreed with Fourier became physicists and those who didn’t became mathematicians, she said.

Wow. So we can blame it all on Fourier? Or maybe some would think that we can thank it all on Fourier! :)

Zz.

Today Is Carl Sagan Day

November 9, 2010 is Carl Sagan Day. Here's a chance for you to learn more about this illustrious astronomer, whose name you may have heard, but whose impact you may not have realized.

Zz.

Possible Observation of Hawking Radiation In A Lab? - Follow-up

I mentioned an earlier news report about the claim of an observation of a Hawking radiation-like radiation using an optical system. The APS Physics has released a very good in-depth description of the work and also allowed everyone to download the paper for free! How about them apples?

Zz.

A Review of One-Way and Two-Way Experiments to Test the Isotropy of the Speed of Light

I try not to highlight preprints on ArXiv until they are published (the exception being if it was a proceeding or a speech, or it is by someone prominent), but this is way too interesting to sit on.

I'm guessing that this is a manuscript for publication. The authors have done a thorough compilation of experiments that test the isotropy of the speed of light, one of the foundational postulates of Special Relativity. It is always nice and convenient to have not only the data, but also to have all the references in one convenient location or document. And this is one such document. One can usually see an improvement in the accuracy of measurement that is commensurate with a lower upper limit in the violation of SR postulate. The exception here being the one-way measurement of the speed of light. Rather interesting.

Zz.

Heavy Ion Collision at LHC

This is a very good article to explain the difference between p-p (or p-pbar) collision, and heavy ion collision, and why they are important. The LHC has recently switched beam source from protons to lead nuclei, and will be studying heavy ion collisions, very much like RHIC. The article has a nice summary on the energy scale that this collision will be relevant to.

As particles collide at higher and higher energies, different physical effects occur. For example, if atoms collide with high enough energies, they knock electrons off each other - they ionise. Experiments which map the cosmic microwave background (like COBE, WMAP and Planck) look at the physics from the moment (about 400,000 years after the start) when the universe got so cool that this ionisation stopped happening. Before that everything was plasma. Plasma is the stuff which glows in fluorescent lightbulbs.

Go further back, a few minutes after the big bang, and energies get so high that even atomic nuclei can't hold together. At this point, protons and neutrons are everywhere. These are the kind of energies you need for nuclear fusion, as is being attempted at ITER.

Back a big step further (about 0.00000000001 seconds after the big bang) and the protons and neutrons can't even stay whole. The quarks and gluons that they are made of spread over the whole universe (which is quite small at this point). This is a new form of matter we refer to as "quark-gluon plasma", though evidence from experiments at RHIC indicates it may behave more like a quark-gluon liquid in fact. This is the stuff the LHC will be able to reproduce now, and which the experiments will study - especially ALICE, which is built for this purpose.

This is a good explanation if you don't understand why, for example, RHIC and CEBAF are a bit different than LHC (when it was doing p-p collision) and the Tevatron, even though all 4 of them are basically particle colliders. They are studying different energy regimes, and possibly different types of processes.

Zz.

Everyday Entanglement

This is a very nice summary of the physics of quantum entanglement. It'll give you a quick synopsis of this phenomenon if you've been asleep these past few decades. If you have followed this blog for any considerable period of time, you would have noticed that we covered many of the examples, papers, and issues mentioned in this article (just do a search).

Zz.