Friday, December 31, 2010

Too-Short History of the Theory of Superconductivity

This is a rather entertaining article (a chapter from a book) written by Jan Zaanen on the history of the theory of high-Tc superconductivity. As everyone knows (or should know), the exact theory for this family of material is still a highly debated and contentious holy grail in condensed matter physics. It is also an area that will have wide-ranging ramifications in not only condensed matter physics, but also in many areas of physics. So knowing the development of the history of the search for this theory might be interesting and important.


Thursday, December 30, 2010

Horsepower Versus Torque In A Vehicle

Here's an informative "basic" classical mechanics, as applied to motor vehicles. Might be something you want to read if you're shopping for new vehicles.

“Horsepower, in physics or engineering terms, is a measure of work, and work is defined as moving something with some force in a certain amount of time. Torque is a force, and can be briefly described as what force it takes to turn an axle or a rod. Horsepower and torque are related based on the speed of the engine,” says Gary Pollak, program manager for ground vehicle standards with the Society of Automotive Engineers (SAE) International.

Don't think I want to quibble about the definition of "work" being "... moving something with some force in a certain amount of time.. ", since this probably makes no difference here.


Wednesday, December 29, 2010

In The Beginning...

This is not a bad article, written by Martin Rees. But then again, I'm a bit disappointed at how sloppy it is in some areas. I'm fully aware that this was written for the general audience, and it appeared in a regular newspaper. But still, he could have made it a bit more accurate without changing the readability of the article.

For example, he wrote this about a possible extra dimension for gravity:

Some have speculated that other universes could exist in tandem with ours. Imagine ants crawling around on a large sheet of paper (their two-dimensional universe). They would be unaware of a similar sheet that is parallel to it. Likewise, there could be another entire universe (with three-dimensional space, like ours) less than a millimetre away from us, but we would be oblivious to it if that millimetre were measured in a fourth spatial dimension, while we are imprisoned in just three.

While the original prediction by Arkani-Hamed et al. predicted millimeter scale compaction, it has now become sub-sub-sub-millimeter scale after several tests have concluded that the Newtonian gravity has not shown any deviation up to sub-micron length scales (or even smaller). So to me, the paragraph above gives the wrong idea that such extra dimension are of the order of just under a millimeter scale. We know quite a bit more now. There is no longer any need to stick with "under a millimeter" when we know it should be under a micrometer, which would be more accurate.

The other part is more puzzling and I don't know why he wrote it.

That said, everything, however complicated - breaking waves, migrating birds and tropical forests - is made of atoms and obeys the equations of quantum physics. But the uncertainties of subatomic physics are irrelevant to biologists; even if those equations could be solved, they would not offer the enlightenment that scientists seek.

This, I don't understand. There are already numerous examples of QM effects in biological system. I've mentioned a lecture given by Seth Lloyd at the Perimeter Institute. And we now have many reports of QM effects in photosynthesis. Someone like Rees should be aware of such advancement. So why would he made a statement that gives the impression that quantum mechanics offers no "enlightenment" to biologists?

{scratching head}


Monday, December 27, 2010

Dubunk Quackery Using Another Quackery

A long time ago, when I found Warren Siegel's "Are You A Quack" webpage, I had quite a chuckle when I came across this piece of information.

Note: Long ago a professor of mine told me that he got letters from 2 quacks, so he forwarded each's letter to the other. He got back an angry letter from one saying, "Why did you introduce me to this quack?"

This is not an isolated incidence. In my encounter on the web after so many years, I find that, often times, quacks can't stand other quacks, or at least, they don't want to make any effort in trying to argue with other quacks, which is understandable. After all, what VALUE is there in such discussion when a quack generally (i) doesn't understand physics and/or (ii) are set in their ways and won't want to learn why he/she is wrong.

So, in this very same spirit, I thought what would be better than using a pseudoscience to counter the argument or another pseudoscience. The pseudoscience that I want to argue against here is "ghosts" or other supernatural beings that go bump in the night. Y'know, the ones you see on either the Travel Channel where they seem to encounter some unknown "forces", "energy", or other beings almost every week, without even a bat of an eye that these things are not verified by science.

So how does one counter the validity of such ghosts? Well, we should pull out "The Secret" and apply the Law of Attraction. The fundamental idea of this Law of attraction is a bastardization of quantum mechanics. Here, it appears that you and your thoughts can somehow affect what goes on around you. Your thoughts can change your world and thus, you are in control of what is happening. This, of course, comes from the bastardization of the act of measurement in quantum mechanics, where these people are erroneously apply the fact that a measurement causes the "collapse" of a wavefunction, and how we measure things can affect the outcome.

So my argument against ghosts is that, when put in a "scary" situation, where you go into a building that you have been told to be haunted, or have supernatural occurrences, then you inevitably, according to The Law of Attraction, are "thinking of thoughts" about ghosts and other goblins. So essentially, your thoughts are the ones bringing these entities into your perception. They would not have been there if you didn't know any better, or didn't know about it. So these ghosts are not real. They are only your imagination, and they are shared by people who are there as well. I bet you, if you bring James Randi to one of these ghosts sightings, he will have a different take on what is going on.

So according to The Secret, you are the one who caused the ghosts that you experienced. How about them apples?


Saturday, December 25, 2010

Italy To Build Accelerator/Collider With US Parts

As further signs that the US truly is going out of particle collider experiments, an agreement has been reached for Italy's SuperB to be built with parts from the now decomissioned PEP-II accelerator at SLAC.

Petronzio says he hopes that the Italian ministry will agree to a construction schedule early next year and that SuperB will start taking data around 2016. The construction of SuperB is contingent on the U.S. Department of Energy (DOE) contributing the machinery of PEP-II, which would be worth more than €100 million. However, David MacFarlane, SLAC's associate director for particle physics and particle astrophysics, says the lab and the agency are onboard with the project: "Both DOE and the laboratory are fully committed to supplying the equipment requested."

Whether U.S. physicists will be able to fully participate in the Italy project is another matter. To support such participation, DOE officials will have to find some room in the agency's already tight $810 million particle physics budget. But David Hitlin, a particle physicist at the California Institute of Technology in Pasadena who has been involved in the project since its inception, says that SuperB presents DOE with a scientific bargain. "DOE can be a major player in the project for a relatively small amount of money by leveraging the in-kind contribution" of the equipment, he says. For the moment, Hitlin says he's just happy that the project seems to be coming to fruition: "It's nice that it's real."

THe US is losing grounds on high energy physics experiments. And no one seems to be concerned about it. Might as well give these equipment to those who appreciate their importance. So Merry Christmas, Italy!


Wednesday, December 22, 2010

Top 10 Reasons to Pursue a Career in Science & Technology

Here's the top 10 reasons to pursue a career in science and technology, from the point of view of Eric Isaacs, the Laboratory Director of Argonne.

Unfortunately, if you're an experimentalist, you can't come in to work in sandals if you're going to be doing experiments that day. :)


Tuesday, December 21, 2010

More Tests Against Realism

The Leggett inequality has been violated in another experiment.

I've mentioned this test earlier in which, even invoking non-locality, certain aspect of realism still cannot survive tests that produced results consistent with quantum mechanics. Now comes a newer test that eliminated even more classes of realism. It is published in New Journal of Physics[1], which is an open access journal and should be accessible to everyone.

Abstract: We report an experimental test of Leggett's non-local hidden variable theory in an orbital angular momentum (OAM) state space of light. We show that the correlations we observe are in conflict with Leggett's model, thus excluding a particular class of non-local hidden variable theories for the first time in a non-polarization state space. It is known that the violation of the Leggett inequality becomes stronger as more detection settings are used. The required measurements become feasible in an OAM subspace, and we demonstrate this by testing the inequality using three and four settings. We observe excellent agreement with quantum predictions and a violation of five and six standard deviations, respectively, compared to Leggett's non-local hidden variable theory.


[1] J. Romero et al., N. Jour. Phys. v.12, p.123007 (2010).

Monday, December 20, 2010

Shatter Metals With Liquid Nitrogen

More fun and educational demo from Jefferson Lab. This time, it shows how one can shatter a metal (pewter) by cooling it with liquid nitrogen. Too bad they didn't spend much time explaining why this happens.


Physics and Diplomacy

Thanks to PhysicsToday Science and Media news for pointing out a terrific letter written by Neil deGrasse Tyson in the NY Times regarding the late Richard Holbrook. It is worth repeating here:

When I gave Ambassador Richard Holbrooke a personal tour of the newly opened Rose Center for Earth and Space and Hayden Planetarium in 2000, I could not help notice how fluent he was in the depth and breadth of his cosmic curiosity.

True science literacy is less about what you know and more about how your brain is wired for asking questions. Later in the tour he confessed that, as an undergraduate at Brown, he studied physics before switching to politics.

I could not resist asking him whether that exposure to physics made a difference in his career as a diplomat, especially in tense, war-torn areas of the world that are resistant to negotiated peace settlements.

He answered emphatically “yes,” citing the physics-inspired approach of sifting for the fundamental drivers of a cause or phenomenon — stripped of all ornament. To get there, one must assess how and when to ignore the surrounding details, which can give the illusion of importance, yet in the end, are often irrelevant distractions to solutions of otherwise intractable problems.

I've written about this many times already on the importance of physics education. When I came up with a series of experiments to revamp undergraduate physics laboratories, I had this very thing in mind. It isn't meant to just train people to become physicists. It is meant to train everyone on how to think analytically, and that figuring out the central principle, be it a physical phenomenon or a political issue, gives one a very systematic approach on how to think things through.

A very nice letter.


Friday, December 17, 2010

Making Cloud In A Bottle

A fun video on making a simple cloud in a bottle.


Tuesday, December 14, 2010

Inflationary Versus Cyclic Universe

I'm guessing that most of you have heard of the battle being done on arXiv between Penrose/Gurzadyan and a number of groups disputing their conclusion. This is being reported on Nature News (which has a limited amount of time for free access).

Simply put, Penrose/Gurzadyan examined the cosmic microwave background data from WMAP and showed that there are these concentric rings of uniform temperature in the CMB. This is not in dispute. What is in dispute is that they concluded that that these are signatures of "... black holes colliding in a previous cosmic 'aeon' that existed before our Universe....", thus, giving an evidence towards a cyclic universe[1].

That led to a flurry of activities, and 3 groups have independently challenged that view[2,3,4].

To gauge this significance, Gurzadyan compared the observed circles with a simulation of the cosmic microwave background in which temperature fluctuations were completely scale invariant, meaning that their abundance was independent of their size. In doing so, he found that there ought not to be any patterns. But the groups who are critical of his work say that this is not what the cosmic microwave background is like.

They point out that the WMAP data clearly show that there are far more hot and cold spots at smaller angular scales, and that it is therefore wrong to assume that the microwave sky is isotropic. All three groups searched for circular variance patterns in simulations of the cosmic microwave background that assume the basic properties of the inflationary Universe, and all found circles that are very similar to the ones in the WMAP data.

Moss and his colleagues even carried out a slight variation of the exercise and found that both the observational data and the inflationary simulations also contain concentric regions of low variance in the shape of equilateral triangles. "The result obtained by Gurzadyan and Penrose does not in any way provide evidence for Penrose's cyclical model of the Universe over standard inflation," says Zibin.

Of course, that's not the end of it. Gurzadyan/Penrose has posted a rebuttal (also on arXiv)[5]. I'm sure there will be more forthcoming to rebut that one as well. People don't even wait anymore for such a thing to be published.

This, btw, is what happens when we try to deduce something using only a set of data and not in possession of other types of data. Often, in such a case, the conclusion isn't unique. You say the data is consistent with A, someone else can also say it is consistent with B. That is why we seldom accept anything to be valid until this non-uniqueness has been sufficiently removed, and Mother Nature clearly points to a single, clear description of such-and-such phenomenon. It is why science can take a very long time to come up with a valid theory of something.


1. Gurzadyan, V. G. and Penrose, R. Preprint at (2010).

2. Wehus, I. K. and Eriksen, H. K. Preprint at (2010).

3. Moss, A., Scott, D. and Zibin, J. P. Preprint at (2010).

4. Hajian, A. Preprint at (2010).

5. Gurzadyan, V. and Penrose, R Preprint at (2010).

Monday, December 13, 2010

Questioning The Radius Of The Proton

A brief highlight of the just published paper out of the Paul Scherrer Institut on a recently-measured proton form factor using a muonic hydrogen. You also (I believe) get a free copy of the actual paper.

It will be interesting to see how CODATA handles this new information, and whether the radius of a proton will have a change in subsequent updates.


Friday, December 10, 2010

The Physics of Holiday Decorations

... or to be specific, the Christmas tree and the Hanukkah menorah (or the Festivus pole if you wish).

PhysicsCentral has an amusing look at how unstable these items are during the holidays, especially when they are fully loaded with decorations.

On a Christmas tree, the majority of the mass is concentrated near the floor. It has a low center of mass. The aluminum Festivus pole's mass is evenly distributed, putting its center of mass right near the center of the pole. For a menorah, with its branches at the top, it's center of mass is higher. That means the menorah would be the most likely to topple.


Tuesday, December 07, 2010

Dear Fellow Quantum Mechanics

I try not to frequently highlight still-unpublished arXiv manuscripts. Some of them are crap and have no place else where they can go. But often, I would find something written by prominent physicists that simply demand to be mentioned. This is one such example.

Jeremy Bernstein has written an entertaining, but at the same time, rather informative view on quantum mechanics, especially on the "measurement problem". You have to read the entire article to get his argument. Along the way, he clarified the uncertainty principle based on what Heisenberg has written:

The uncertainty principle refers to the degree of indeterminateness in the possible present knowledge of the simultaneous values of various quantities with which the quantum theory deals; it does not restrict, for example, the exactness of a position measurement alone or a velocity measurement alone. Thus suppose that the velocity of a free electron is precisely known, while the position is completely unknown. Then the principle states that every subsequent observation of the position will alter the momentum by an unknown and undeterminable amount such that after carrying out the experiment our knowledge of the electronic motion is restricted by the uncertainty relation. This may be expressed in concise and general terms by saying that every experiment destroys some of the knowledge of the system which was obtained by previous experiments.
This formulation makes it clear that the uncertainty relation does not refer to the past: if the velocity of the electron is at first known and the position then exactly measured the position for times previous to the measurement may be calculated. Thus for the past times ΔxΔp is smaller than the usual limiting value, but this knowledge of the past is of a purely speculative character, since it can never (because of the unknown change in momentum caused by the position measurement) be used as an initial condition in any calculation of the future progress of the electron and thus cannot be subjected to experimental verification. It is a matter of personal belief whether such a calculation concerning the past history of the electron can be ascribed any physical reality or not.

You will note that this is consistent with my earlier blog entry on the misconception of the HUP.

Still, the most fascinating aspect of this article is Bernstein's assertion about the observer based on Dyson's writing:

My second general conclusion is that the ``role of the observer'' in quantum mechanics is solely to make the distinction between past and future. The role of the observer is not to cause an abrupt ``reduction of the wave-packet'', with the state of the system jumping discontinuously at the instant when it is observed. This picture of the observer interrupting the course of natural events is unnecessary and misleading. What really happens is that the quantum-mechanical description of an event ceases to be meaningful as the observer changes the point of reference from before the event to after it. We do not need a human observer to make quantum mechanics work. All we need is a point of reference, to separate past from future, to separate what has happened from what may happen, to separate facts from probabilities.

You also get a little provocative challenge at the very end of the article in which the scale of the Planck's time measured by a clock violates SR? Hum?

Like I said, whether you agree with the article or not, it is highly fascinating. :)


Sunday, December 05, 2010

Science Versus Religion Battle in Israel

This is a very different battle between science and religion in Israel. If you think the battle here in the US is "complicated", wait till you read about the battle there!

So the battle in Israel between advocates of science and advocates of Torah, surprisingly ends up to be not about an angry disagreement, but a profound agreement. Both sides agree that science education offers a road from being a Talmud scholar living on the dole who's never heard of Madam Curie to being an SUV-driving systems analyst who can't get enough of Lady Gaga.

All they disagree about is whether this is a road worth traveling.

It'll be interesting to see how this plays out.


Saturday, December 04, 2010

"X" Marks The Spot

A lot of brouhaha has been going on this past week or so on the speculative particle called the "X" particle. The model for the existence of this particle could, in principle, explain the dark matter problem, and also the matter-antimatter imbalance of our universe.

Check out this MSNBC article, that gives you links to other articles, on this topic in case you missed it.


Thursday, December 02, 2010

The Physics of X-Ray Backscattering at Airports

I'm back and severely jet-lagged. So it'll be a couple of days before I'm back up to speed with what's been happening. But yours truly got his first full-body scan at O'Hare on this past trip. Yippee!

I couldn't figure out if it was the X-ray backscattering or the millimeter wave technology. I was about to ask one of the TSA's officer what it was, but they were all rather busy at that time, and I was already "loitering" about the area for a few minutes. After giving it a thought, I decided not to risk raising suspicion about being too curious about the scanning technology and left.

Anyway, if anyone wants to look at the issue surrounding the millimeter wave technology, check out an earlier blog entry. Ars Technica has a good article covering the x-ray backscattering technology.

Happy traveling!


Thursday, November 18, 2010

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....


Wednesday, November 17, 2010

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".


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.


Tuesday, November 16, 2010

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? :)


Monday, November 15, 2010

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.


Sunday, November 14, 2010

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.


Saturday, November 13, 2010

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.


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?


Friday, November 12, 2010

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.


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.


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

Thursday, November 11, 2010

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.


Wednesday, November 10, 2010

"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.
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!


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."


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.


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.


Tuesday, November 09, 2010

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! :)


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.


Monday, November 08, 2010

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?


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.


Sunday, November 07, 2010

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.


Saturday, November 06, 2010

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).


Bronx Physics

An interesting coverage of an amazing high school in the US, Bronx High School of Science, that has produced SEVEN Nobel Prize winners in physics.

On 15 October this year, Bronx Science, as it is colloquially known, was officially designated a "historic physics site" in a ceremony organized by the American Physical Society (APS). The high school joins an imposing list of 18 other landmarks with that status. They include Bell Labs in New Jersey, where the transistor was discovered, the Massachusetts Institute of Technology's Radiation Laboratory, which helped to develop radar, the University of Chicago site where Robert Millikan measured the charge on the electron, and the spot outside Cleveland, Ohio, where Albert Michelson and Edward Morley did their epochal ether-drift experiment.

Located in the northwest corner of New York City, Bronx Science owes its historic status to the fact that seven future Nobel-prize-winning physicists went through its doors – more than any other high school in the world and more than most countries have ever achieved. The school, which opened in 1938, was founded by the educator Morris Meister, who believed that if a school put bright students together, it would kindle ill-defined but valuable learning processes. The school seems to have proved him right: according to the Bronx laureates, their physics learning took place mainly outside the classroom.

It is fitting that it became a physics historic site here in the US.


Friday, November 05, 2010

An Interview With Albert Einstein

This is a rather "interesting" way of doing it. Science News Editor-in-Chief Tom Siegfried "conducted an interview" with Albert Einstein on his objection to quantum mechanics. Einstein's responses were based on his writings on the subject.

I suppose that for many of us who are familiar with this history, there's nothing surprising here. However, if we were to conduct this interview today, one certainly cannot ignore the dramatic advancement we have made with the Bell-type family of experiments, something that Einstein didn't live to see. So presumably, he didn't have much to say about this phenomenon and so, this "interview" could not speculate on what his response would be if we were to present to him such a question. To be, that would be the question that I would pose, and I would be highly curious on his response to it.


Thursday, November 04, 2010

Physics Doctorate - One Year Later

The AIP has just released the result of a new statistics that polled Physics Ph.Ds on the state of their career one year after they received their degrees. The result comes from degree recipients from the class of 2007 and 2008, so the poll was conducted right in the height of the economic crash.

Interestingly enough, the percentage of Ph.Ds in postdoctoral position continues to decline, while those getting potentially permanent position increased. What is also interesting is that, no matter what the unemployment situation is in the US, the unemployment rate of physics Ph.D remained relatively unchanged throughout the years.

Foreign citizens continue to go into the postdoctoral position more than US citizens. Understandably, they do not have a higher percentage that are in a potentially permanent job position than US citizens 1 year after their degrees.

Would be interesting to compare this with the initial employment right after graduation.


Quantum Mechanics in Biology

This appears to be a report on a lecture given by Seth Lloyd at the Perimeter Institute. It covers how various biological organisms or functions work via quantum mechanics.

Bird navigation, plant photosynthesis and the human sense of smell all represent ways living things appear to exploit the oddities of quantum physics, scientists are finding.

Supposedly, the video of this lecture will appear on the Perimeter Institute website, but as of this morning, it isn't up yet.


Wednesday, November 03, 2010

Topological Superconductor?

We know how "hot" topological insulator is right now in condensed matter. Huge amount of publications are pouring out on this family of material. Well, it seems that in one type of topological insulator, B12Se3, when doped with copper, it becomes what is claimed to be a topological superconductor! This is where the material becomes a superconductor in the bulk of the material, but still becomes a normal metal on the surface.

Generally, metals, insulators and conventional superconductors tend to have a single type of behavior as far as electricity goes. They can either conduct current or not, and remain consistent in they way they respond to electrical charges.

“The known states of electronic matter are insulators, metals, magnets, semiconductors and superconductors, and each of them has brought us new technology,” explains M. Zahid Hasan.

“Topological superconductors are superconducting everywhere but on the surface, where they are metallic; this leads to many possibilities for applications,” adds the expert.

Here is the abstract from the Nature Physics paper[1]:

Experimental observation of topological order in three-dimensional bulk solids has recently led to a flurry of research activity. Unlike the two-dimensional electron gas or quantum Hall systems, three-dimensional topological insulators can harbour superconductivity and magnetism, making it possible to study the interplay between topologically ordered phases and broken-symmetry states. One outcome of this interplay is the possible realization of Majorana fermions—quasiparticles that are their own antiparticles—on topological surfaces, which is of great interest in fundamental physics. Here we present measurements of the bulk and surface electron dynamics in Bi2Se3 doped with copper with a transition temperature Tc up to 3.8 K, observing its topological character for the first time. Our data show that superconductivity occurs in a bulk relativistic quasiparticle regime where an unusual doping mechanism causes the spin-polarized topological surface states to remain well preserved at the Fermi level of the superconductor where Cooper pairing takes place. These results suggest that the electron dynamics in superconducting Bi2Se3 are suitable for trapping non-Abelian Majorana fermions. Details of our observations constitute important clues for developing a general theory of topological superconductivity in doped topological insulators.


[1] L.A. Wray et al., Nature Physics v.6, p.855 (2010).

What Is Quantum Mechanics Good For?

This is a question I get on a regular basis. I even see it in the news when politicians belittled some basic research that he/she didn't understand and thus, could not see the implications.

This interview article with James Kakalios on his book "The Amazing Story of Quantum Mechanics" has just enough details to pacify such a question on what QM is good for.

I present in the introduction what I call a "workingman's view" of quantum mechanics and show how if you accept on faith three weird ideas—that light is a photon; that matter has a wavelength nature associated with its motion; and that everything, light and matter, has an intrinsic angular momentum or spin that can only have discrete values—it turns out that you can then see how lasers work. You can see how a transistor works or your computer hard drive or magnetic resonance imaging—a host of technologies that we take for granted that pretty much define our life.

There were computers before the transistor; they used vacuum tubes as logic elements. To make a more powerful computer meant that you had to have more vacuum tubes. They were big, they generated a lot of heat, they were fragile. You had to make the room and the computer very large. And so if you used vacuum tubes, only the government and a few large corporations would have the most powerful computers. You wouldn't have millions of them across the country. There would be no reason to hook them all together into an Internet, and there would be no World Wide Web.

The beautiful aspect to this is the scientists who developed this were not trying to make a cell phone; they were not trying to invent a CD player. If you went to Schrödinger in 1926 and said, "Nice equation, Erwin. What's it good for?" He's not going to say, "Well, if you want to store music in a compact digital format..."

But without the curiosity-driven understanding of how atoms behave, how they interact with each other, and how they interact with light, the world we live in would be profoundly different.

I've always believed that as a physicist, you need to have a set of "here's what this was used for" examples on your back pocket at all times. When someone asked you "what is so-and-so good for?", you should be able to whip out immediately the direct application to such a thing.

Now, granted, some areas of physics will be more difficult for us to do that than others. However, you should always have a read-made answer, and the way Kakalios tackled in the above example of QM is the way it should be dealt with.


Tuesday, November 02, 2010

Possible Detection of Sterile Neutrinos?

It looks like the MiniBooNE experiment is producing very tantalizing results that might point to the existence of sterile neutrinos.

An electron neutrino might become a muon neutrino, and then later an electron neutrino again. Scientists previously believed three flavors of neutrino exist. In this Mini Booster Neutrino Experiment, dubbed MiniBooNE, researchers detected more oscillations than would be possible if there were only three flavors.

"These results imply that there are either new particles or forces we had not previously imagined," said Byron Roe, professor emeritus in the Department of Physics, and an author of a paper on the results newly published online in Physical Review Letters[1].

"The simplest explanation involves adding new neutrino-like particles, or sterile neutrinos, which do not have the normal weak interactions."


[1] A. A. Aguilar-Arevalo et al., Phys. Rev. Lett. 105, 181801 (2010).

Monday, November 01, 2010

2010 Jefferson Lab Open House

Video highlights from this year's Jefferson National Laboratory Open House.

As I've said numerous times, if you have the chance to visit any of the US National Labs, especially during one of these open houses, don't miss the opportunity. Not only do you get to see many amazing research facilities, you get to talk to the scientists and engineers who are passionate about what they do, and get first-hand information on a lot of things.


Is the International Space Station Worth $100 Billion?

For many, the answer to that question is a resounding "no". Bob Park is certainly one of the many critics of the ISS, something you would have noticed if you have followed his "What's New" regularly.

This article examines the ISS as it approaches what could be an important phase in its existence.

Now, as NASA celebrates the 10th anniversary of astronauts living on the space station — and with construction essentially complete, the question remains — will the International Space Station ever really pay off scientifically?

In many facilities, the "worth" of such facility is justified by either (i) the amount of scientific publication emanating from work done at such a facility and/or (ii) the level of ground-breaking work produced from work done at such facility.

Can the ISS show such a thing?


Sunday, October 31, 2010

Abdus Salam Ignored In The Muslim World?

As THE most prominent muslim physicist, one would think that Nobel Laureate Abdus Salam would be celebrated in the muslim world. But it appears that he isn't for reasons that we have seen repeated over time and in many different religions. The writer of this article highlighted why his name is missing in a festivities to celebrate Canada's Islamic History Month.

Salam (1926-96) was born in Jhang, Punjab, in British India. The 1947 partition of India made Salam a Pakistani. His family belonged to the Ahmadiyya sect in Islam founded by Mirza Ghulam Ahmad (1835-1908), an autodidact scholar of Arabic and Persian, who claimed to be a messiah or renovator of faith in 1889. The followers of Ahmad grew in number during the British Raj despite the fierce opposition of orthodox Muslims. Their circumstances, however, changed for the worse following India's partition.

During Pakistan's early years Ahmadis experienced hostility, yet the government remained neutral and protective of them. This changed in the 1970s when Ali Bhutto's government under Saudi Arabia's influence declared the Ahmadiyya sect to be outside of Islam, and formally branded Ahmadis as non-Muslims. Since then Ahmadis have faced persecution as apostates and blasphemers in Pakistan, Saudi Arabia and wherever in the Muslim world the Wahhabi version of Saudi Islam finds favour among people, as in Afghanistan.

Like I said, such religious persecution happens in almost every religion and beliefs over different times. It is sad that such an outstanding person is being totally ignored. It is not as if he's a murderer, or did some heinous crime.


A Zombie Steven Chu

Our US Energy Secretary commented on his Facebook page on how cool he looks as a zombie. He doesn't think there's evidence that zombies exist (neither do I), but then he talks about vampire appliances.

To date, there is no scientific evidence about the existence of Zombies, but what about vampires? Actually, when it comes to energy, they are all too real. “Vampire appliances” – from DVD players to stereos to desktop computers -- suck up energy even when they are turned off. In fact, these vampires are responsible for adding 10 percent or more to your monthly electricity bill.

That's scary. So Happy Halloween, everyone!


Friday, October 29, 2010

Liquid Nitrogen and the Tea Kettle Mystery

Another fun and educational video from Jefferson Lab.

You may catch up with the previous videos in one of my earlier blog entry.


Physics Teaching Technology Resource

I came across this website at Rutgers University in the new edition of Science. Physics Teaching Technology Resource looks extremely useful, and the brief description of its motivation as stated in the Science article is spot on!

The Rutgers Physics Teaching Technology Resource engages students from middle school to college in the process of physics. It contains more than 200 videos of real-life physics experiments that students can view and analyze as they learn new material, perform labs, carry out independent projects, or do homework. Videos allow them to see physical phenomena in real time and then again in slow motion for data collection. The videos do not contain tools for quantitative analysis. Instead, students need to decide themselves what data to collect and how to collect them. The goal is to engage students in actions and decisions similar to those of real physicists by working with simple experiments.

Physicists observe physical phenomena, collect data, find patterns in the data, and devise multiple explanations or mechanisms behind the patterns, test those explanations with more experiments, and apply their theories to solve real-world problems. Although it is a complex and nonlinear process, its logic can be used in physics instruction. A physics learning system called Investigative Science Learning Environment (ISLE) models this process for the students. In ISLE, all experiments that students encounter can be placed into one of three categories according to their roles: observational (experiments that are used to generate explanations), testing (used to test explanations), or application (experimental problems to solve for which one needs to synthesize multiple explanations and/or relations). The video Web site follows this scheme, helping an instructor form a learning progression that mirrors the process of doing physics.

Physics teachers and instructors might find this quite useful.


Thursday, October 28, 2010

Fusion - From Here To Reality

An informational video from Physics World on Fusion and ITER. It is more of an interview and Q&A. A bit dry, but it's informative.


Best Physics App

No, I'm not starting another poll, so let's get that out of the way first. :)

Do you have a favorite physics app that you've found for your smartphone? There's been a lot of apps being written for the iPhone/iPad, Android phones, and Blackberry. Still, are there really good and/or useful apps in physics? I have a Blackberry, and the only stuff that I've found that would be remotely considered to be useful for physics work would be the standard, generic stuff - periodic table, scientific calculator. I find that I use the browser more often to look up stuff, rather than rely on apps. But then again, there aren't that many apps for the Blackberry when compared to Android and iOS phones.

So, have you found apps in physics for Smartphones that you think are quite useful?


Wednesday, October 27, 2010

The "Relavistic" Mug

Lev Okun tries again to correct the error in thinking about relativistic mass. I mentioned last time about his rather compact paper that tries to crush the erroneous notion of a "relativistic mass". This time, he does that based on things he read on, of all things, a mug!

Recently my friends added to my collection a Relativity Floxy Noxy mug.
In a certain sense it contains the quintessence of my collection presenting the main popular science clich`es and misconceptions. As they are quite often repeated in newspapers and textbooks, I decided to reproduce the text on the mug and to explain briefly what is wrong with it. I believe that it may be useful to many people.

You'll have to read his preprint to know what's written on the mug and how he tackled it into an issue of a misrepresentation of "mass".


Tuesday, October 26, 2010

How To Build A Cloud Chamber

More fun instructional videos from Jefferson Lab. This time, they teach you how to build a simple cloud chamber.

So, talking about safety, shouldn't the woman wear safety glasses, especially when the isopropanol is being squirted? The MSDS that was referred to indicated that one should wear eye protection, and gloves.

Read my previous blog entry to see other videos in this series.


Monday, October 25, 2010

Unpopular Science

This is a rather amusing interpretation of the various principles and laws of physics/science. I bet you haven't seen it illustrated like this before.


Sunday, October 24, 2010

Physicists and Poker

A rather amusing article on physicists and poker. I didn't think physicists, or at least, some of them, have such affinity towards poker.

But a little research revealed there are a lot of poker-playing physicists, some of whom are pretty serious about the game.

Physicist Michael Binger placed third in the 2006 World Series of Poker, winning $4 million. Two others, Michael Piper and Liv Boeree, competed last spring in a tournament in San Remo, Italy. Piper placed fourth, and Boeree won, racking up $1.6 million. Ouelette's husband, CalTech cosmologist Sean Carroll, entered a Chicago tournament in 2004 and, to his surprise, met three other poker-playing physicists, including Harvey.

I suppose the game of poker is one thing, while other gambling games at a typical casino is another. The latter tends to have odds very much in favor of the house, so anyone with any sense of chance and probability will know that sooner or later, the house will get the better of you.


Friday, October 22, 2010

Penthouse Magazine Founder and Fusion Research

Who knew? I certainly didn't.

With the passing this week of Bob Guccione, the founder of Penthouse Magazine, we now have various information about him that I didn't know before. For example, he founded the science magazine Omni (not one of my favorite magazines). Still, what was surprising to me was that he was fascinated with fusion and invested quite heavily in a company to develop a workable fusion reactor.

Bussard, who had previously worked on fusion at Los Alamos National Laboratory, had set up a company, International Nuclear Energy Systems Company (Inesco) to develop a compact tokamak design he had devised. His innovation was to equip the device with extremely powerful electromagnets to allow it to heat a small volume of plasma to high enough temperatures so that nuclei would fuse and generate heat. Mainstream tokamaks were getting larger and larger in an effort to reduce heat loss.

According to Robin Herman in her book Fusion: The Search for Endless Energy, Guccione invited Bussard over to dinner and heard about his trouble getting government funding or private investors. In 1980, Guccione decided to back the project with an initial $400,000.

Bussard set up the business in San Diego, California, and soon had a staff of 85. Other investors failed to materialize, and Guccione eventually sank up to $17 million in the project. When a public share issue for Inesco in 1984 flopped, the pair were forced to wind up the project.

Interestingly enough, as pointed out in that Science news article, one of Bussard's said is Bruno Coppi of MIT, who made a news splash recently with his Ignitor project that I mentioned recently as a small-scale alternative to ITER. So Bussard's and Guccione's legacy sort of continues in some form and shape.

Soft porn and fusion? Who knew?


Thursday, October 21, 2010

The Wet-Dog Shake

Continuing with items on our physics of the mundane, which I really love, this time we have a rather amusing investigation. I'm sure most of us have seen this. A wet dog gets out of a pool or a water sprinkler, and gets ready to really shake its body to get ride of all that accumulated water. At what rate/speed does it shake its body to get rid of most of the water?

That is the study that was conducted by Andrew Dickerson and his colleague at Georgia Tech, and was published in Fluid Dynamics journal.

The team built a mathematical model of the processes involved, reasoning that surface tension between the water and the dog's hair is what keeps the dog wet. Overcoming that tension requires a centripetal force that exceeds it.

As centripetal force varies with distance from the centre of the creature, its radius is therefore crucial to work out the speed of the oscillations. The team arrived at an equation that calculates the frequency of that oscillation as R0.5.

To test that hypothesis, the team filmed a wide range of dogs shaking, and used the images to calculate the period of oscillation. For a labrador retriever, that turned out to be 4.3 Hz. He then expanded the search, filming animals as small as mice (27Hz) and as large as bears (4 Hz).

Here's the video that accompanied this article:

So the bigger the animal, the slower it can shake to achieve comparable drying, but the relationship isn't linear. Instead, it approaches a limit of 4Hz as an animal grows in size.

A preprint version of the paper can be found on Arxiv.

How many wet investigators that resulted in this study? :)

Can I say it once again how much I love things like this. You guys can go ahead and try to find the meaning of life, and why we're here, and how the universe began. Go at it and call me when you find out. But give me stuff like this that, while it appears to look mundane, can have wide-ranging application that most of us don't know about when we study such things. These things can be fascinating by itself, and the fact that they can have important implications for other systems is simply a pleasant bonus. Kids and students should be exposed to these kinds of curiosity, because these are the things that they can see and understand. Being curious and trying to understand how things happen is what physics is all about.


Wednesday, October 20, 2010

Scientists Versus Engineers

It seems that the severe budget cuts in the UK has cause a long-standing crack between the perceived importance of science over engineering to surface.

Science is mainly concerned with unearthing knowledge. Engineering seeks to deliver working solutions to practical problems in the form of technology. Yet the terms 'engineering' and 'technology' have been increasingly subsumed into 'science' — in the names of institutions, in discussion of 'science policy', in media coverage and in popular parlance. The situation upsets engineers and their leaders, but they tend to keep quiet for fear of being accused of having chips on their shoulders.

Now that public money is scarce for both the science and engineering communities, the fault line between them has started to creak. In the run-up to this week's UK Comprehensive Spending Review, Martin Earwicker, a vice-president at the Royal Academy of Engineering (RAEng), wrote to The Times to point out that engineers are needed to turn a scientific discovery into hard cash. It was a "logical leap that is not in general supported by experience", he wrote, "that a scientific discovery, however important, will automatically turn into economic success."

I must admit that I have been totally ignorant of the sentiments reflected here by engineers or the engineering profession. So I can't really comment on the validity of such sentiments. However, from my perspective as a scientist (physicist), there are two major points that should be pointed out:

1. Engineers as a profession tend to have a greater degree of employability than scientists, and the tend to make more money as well. So this is not a suppressed, down-trodden, poor profession. In fact, they are quite well off when compared to the physics profession. So to hear this type of comments from the engineering profession of not being given any respect is like Donald Trump complaining that he isn't given the same level of respect as, say, Steven Chu.

2. I can also see why government spending would tend to favor spending on science rather than engineering. I'm not saying there shouldn't be any spending on engineering. That would be silly. However, spending on science tends to be "riskier", and it isn't something the private industries generally are willing to invest in. This is where the government can step in and fill such voids. Now, once a discovery has been made, then turning a scientific idea into something useful and commercial can and should be done by private industries, where profits can be made. This is where engineers step in where they take a science idea, and then refine it to turn it into something useful. I do not see this as a denigration of the engineering profession. In fact, it clearly shows the vital link between science and engineering, where an idea turns into a useful product. In fact, one could argue that the amount of money put into engineering research and effort dwarfs money spent on science, as indicated in the article:

The RAEng said in its submission that each active research academic in physics and maths gets 'several times more expenditure' than those in engineering and technology. But industry spends twice as much — about £15 billion (US$23.8 billion) — as the UK government on research and development each year, and most of that industrial money supports engineering, not science. In addition, state programmes that concentrate on applied work — such as the European Commission's Framework Programme — tend to be more politicized, less meritocratic and less efficient than science programmes such as those of the US National Science Foundation.

In fact, advances in engineering allows for the ability to advance science. Better detector and measuring devices are crucial aspects in the ability of scientists to study even more difficult subjects to greater precisions. So this is almost like a closed, feedback loop where there is a symbiotic relationship. I don't know of any scientist that I work with that do not value the impact of engineering on our profession. But then again, we're experimentalists.


Redefining The Kilogram

Is this the last of our standard metrology that isn't tied to a fundamental constant? It might be.

There is a push to redefine the kilogram into something beyond a mass kept in a lab somewhere. While standard length of 1 meter and standard time of 1 second are tied to various fundamental constant, the standard mass of 1 kilogram is still tied to some fiducial object. This latest attempt at a precise measurement of Avogadro's number using silicon-28 strengthened the case to redefine the kilogram.

The latest result from a team led by Peter Becker of the Federal Institute of Physical and Technical Affairs (PTB) in Braunschweig, Germany, published on arXiv (P. Andreas et al. Preprint at; 2010), comes closer than ever to ending the cylinder's reign. The team has measured the number of atoms in a sphere of silicon-28 to calculate Avogadro's constant to nine significant figures: 6.02214084(18) × 1023 mol−1. The constant refers to the number of atoms in a sample whose bulk mass in grams equals the relative atomic mass of the element. This general relationship makes Avogadro's constant a fixed point from which to define mass.


Tuesday, October 19, 2010

String Theory Tackles Strange Metal

Forget about high energy physics or elementary particles. The testing grounds for String Theory is condensed matter physics!


As if you are not convinced already by all the possibilities presented with the topological insulator, we now have even more ideas that various aspects of String Theory can be analogously tested in condensed matter. I mentioned a paper a while back that suggested that an aspect of String theory might explain the phenomenon of high-Tc superconductors (among other things). Well now, a new paper just published in PRL[1] extended that work and used it to come up with a model to describe the strange metal state of these cuprate high-Tc superconductors.

In 2003, condensed matter physicist Subir Sachdev of Harvard University, in Cambridge, Massachusetts, and his colleagues, put forward a new model called fractionalized Fermi liquid (FFL) that seemed to account for some of the properties of strange metals, including the variation of their resistance with temperature1. Unlike in the standard Fermi liquid model, the quantum mechanical spins of some electrons in the material are linked together in an FFL.

Now, in a paper published in Physical Review Letters2 on 4 October, Sachdev shows that the FFL model's characteristics match those of a type of black hole in string theory. "We're still a long way from saying string theory explains strange matter but we have hope," Sachdev says. "It's very exciting because it's a whole new perspective." He adds that he's been learning string theory at a breakneck speed.

We'll have to see how far this can be taken.

[1] S. Sachdev et al., Phys. Rev. Lett. v.105, p.151602 (2010).

High-Energy Astroparticle Physics

A very useful overview of astroparticle physics, which is the merging of knowledge and capabilities from high energy physics and astrophysics.

Abstract: In these three lectures I discuss the present status of high-energy astroparticle physics including Ultra-High-Energy Cosmic Rays (UHECR), high-energy gamma rays, and neutrinos. The first lecture is devoted to ultra-high-energy cosmic rays. After a brief introduction to UHECR I discuss the acceleration of charged particles to highest energies in the astrophysical objects, their propagation in the intergalactic space, recent observational results by the Auger and HiRes experiments, anisotropies of UHECR arrival directions, and secondary gamma rays produced by UHECR. In the second lecture I review recent results on TeV gamma rays. After a short introduction to detection techniques, I discuss recent exciting results of the H.E.S.S., MAGIC, and Milagro experiments on the point-like and diffuse sources of TeV gamma rays. A special section is devoted to the detection of extragalactic magnetic fields with TeV gamma-ray measurements. Finally, in the third lecture I discuss Ultra-High-Energy (UHE) neutrinos. I review three different UHE neutrino detection techniques and show the present status of searches for diffuse neutrino flux and point sources of neutrinos.


Monday, October 18, 2010

The Musical Turkey Baster

Another physics in the kitchen, and this time, you get instructions on how to turn your turkey baster into a musical instrument. Hey, after all, here in the US, Thanksgiving is barely a month away.

Inside the tube of the turkey baster is a column, or chamber of air. When you blow over the edge of the turkey baster, its edge vibrates, compressing the air inside the tube at equal intervals. The compressed air moves down the column and bounces back toward the opening once it hits the water. By doing this, you have created a standing wave, a wave that remains at a constant position. When you change the water level, it changes the wavelength of the standing wave.

So you get to learn about sound in a standing wave with stuff you find around your house.


Interview With Anton Zeilinger

PhysicsWorld has an interview with Anton Zeilinger. Anyone who has followed progress in physics these past few years would know that name very well. Zeilinger has made several landmark experimental and theoretical advances in our understanding of quantum mechanics, especially on the property of quantum entanglement/teleportation.

So if you haven't read the provocative interview yet, don't miss it.


Saturday, October 16, 2010

Your Quantum Superpowers

A rather fun interview with James Kakalios (he the author of "The Physics of Superheroes") on his new book "The Amazing Story of Quantum Mechanics". In the interview, he answered the question on why ordinary citizens want to not only learn about the basics of QM, but also why they should realize that research in fundamental knowledge has led to the advancement that we take for granted today.

Q: Are there aspects of this that you feel are particularly important for voters, considering that we have an election season upon us?

A: The bottom line is, when you see all of the benefits that have accrued to us through these applications of basic scientific research, you get a sense that basic science really matters. Recently there's been a tendency to denigrate scientists. People take the titles of certain research grants out of context and ridicule them. But people will explore different things for very different reasons. These are usually peer-reviewed proposals. Many proposals get rejected, but the ones that get accepted are projects where other scientists see true value.

The world is a knowable place, and science is a way of providing that knowledge. The philosophy that guides my book is the idea that science is not "just another opinion." You can argue about, say, the age of the earth, but science provides an answer. We may have to improve on the answer and refine it, but we all agree on the criteria for the answer. It's not just an opinion. It provides you with something you can really depend on. If you don't believe in science, that's fine, but at least put the cell phone down.

A couple of video accompany this interview, which I've included in here as well.


Friday, October 15, 2010

Resource Letter: Quantum Chromodynamics

I always like these "resource letter" in AJP. They are chokeful of useful and valuable references, and having them right at your fingertips in one document is extremely handy.

This is one such example, and this time, it is on QCD. Anyone just learning about QCD will find the references very handy. It cuts down on the time hunting for the majors papers in the various topic in QCD.


Baseball Zany Pitches Are Visual Illusions?

Here's a close examination on how our eyes perceive things that may not be correct. This is applied to the trajectory of an object that is spinning versus one in which we can't perceive it to be spinning, which is relevant to baseball.

The key to the phenomenon, says Shapiro, is understanding how the human visual system works. One of its two components, the fovea, or central visual area, can track motion very well. The region around the fovea provides our peripheral vision; it can detect only motion and can't track it very well. "We often confuse different signals in peripheral vision," adds neuroscientist and co-author Zhong-Lin Lu of the University of Southern California (USC) in Los Angeles. "For example," he says, "if we see a moving car with our peripheral vision, we may confuse [its movement] with any movement in its immediate background."

Regarding baseballs, the problem is that the fovea can focus on only a very small area—only about 2 degrees of the visual field (or an area smaller than your thumbnail held at arm's length)—so as a pitched ball moves closer it can easily slip into your peripheral vision as it becomes larger. When that happens, Shapiro explains, the movement and spin of the ball combine in the hitter's mind and create the perception that the ball is veering off track. Hence, curveballs seem to curve more, fastballs seem to break, and the best hitters in baseball succeed in getting a hit only about three times in every 10 at bats.

The work is available online, and you can even try the visual test done in the study. TRY IT! It is astounding!

Relying on our eyes alone as accurate description of something is not sufficient. It is another reason why anecdotal evidence can't be trusted as valid.


The Physics of the "Mundane"

I got interested in physics not because of some grandiose idea of wanting to know why we exist, or how the universe came to be, etc. I didn't have, and don't have, such lofty goals. Maybe I'm not smart enough to want to ask those questions. Rather, I love physics because of its ability, or at least its potential capability, to solve or explain ordinary, and apparently "mundane" phenomena. These seemingly-simple things are what fuel my curiosity.

The Buzz Blog on Physics Central has a bunch of such mundane phenomena, with videos of them. One may be tempted to argue that studying and trying these things may be a waste of time. But as mentioned at the end of the blog entry, these things can, in fact, be an avenue to understand more important phenomena. After all, who would have thought that just trying to understand an apple falling from a tree could provide an understanding of how to build large structures and how celestial bodies move.


Thursday, October 14, 2010

New Ion Beam Source for Brookhaven Accelerators

An informational video describing new ion beam source for accelerators at RHIC and NSRL at Brookhaven Lab.


Photocathode for Photoinjectors

I've been attending a workshop this week on photocathodes for photoinjectors. With more stringent requirements and more demanding environment that these photocathodes are subjected to (example: higher field gradients, extremely low emittance, etc.), there is a deliberate effort to understand even more the physics of photocathodes and photoemission processes using various materials and processing techniques.

Historically, most of the emphasis has been on getting a stable photocathode, or something with sufficient quantum efficiency (QE) with long lifetimes. Metal photocathdoes have been the workhorse for many photoinjectors (such as synchrotron light sources) because they are relatively easier to fabricate, long life times, and not very fussy. But metals such as copper or niobium have very low QE, and with new demands on producing high brightness electron beam, new materials, or new processing/treatment are being investigated.

What is very exciting now in this area of study is that, there is a new influx of experts from the condensed matter/material science field studying photocathodes specifically for accelerator photoinjectors. This is important because, while there have been such experts scattered around studying these photocathodes, there hasn't been a coordinated effort to get more of these experts in, both with theorists or experimentalists. CM theorists are needed because there are many aspects of the photoemission process that resulted in high QE and low emittance beam that needed to be modeled or explained. Experimentalists are needed because they have a wealth of material characterization knowledge that are needed to study the nature of the surface and the nature of the material, and they provide feedback to theorists to make accurate models. At this workshop, there is a major presence CM theorists and experimentalists, and I think people in both accelerator physics and condensed matter/material science/physical chemistry realize that there's A LOT of work that can be done in the study of photocathodes, even though a lot has already been known.

I'm very excited with this development. As someone who came from condensed matter physics and now working in accelerator physics, I've always realized the importance of these two fields getting together and combining their expertise to solve the various problems in photocathodes. In fact, this issue doesn't just affect the application of photocathodes to accelerator photoinjector. It has a direct consequence to many photocathode applications, such as photodetectors, and this includes things such as high energy physics detector (neutrino detectors) and even night-vision goggles. So the impact of the understanding of a better understanding of the physics can be very wide.