Arsenic Poison Didn't Kill Napoleon

Another myth bites the dust.

A new study by physicists at INFN in Milano-Bicocca and Pavia, Italy, has shown that there's no difference in the arsenic level in Napoleon's hair during his last days when compared to when he was a child. This means that he wasn't deliberately poisoned by arsenic during his last days. Instead, it was more likely that it was due to a lifetime's worth of exposure to arsenic.

Zz.

On Vacation

Hello Folks,

I'm on an extended vacation right now till May 18th. So there will be little to no updates at all in this blog till I get back.

Cheers!

Zz.

Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks

I just want to say that I had a lot of fun reading this preprint by Joseph Kapusta. It is entertaining, insightful, and has a ton of information for both scientists and non-scientists alike. It reinforces the point that I've been trying to make, which is the constant miscommunication between scientists and non-scientists. The blame goes on both sides - scientists for not considering how what they say is being interpreted by the public, and the public for not self-educating themselves into trying to understand not just the science, but the vocabulary that science uses. Not being aware that there are discontinuity in the communications and understanding of the two parties is the first significant problem. This is also a very good opportunity to again highlights the wonderful essay written by Helen Quinn that I've mentioned a while back. Everyone should read it!

If you have some time, I'd recommend reading this article by Kapusta, even for just for its "storytelling" aspect.

Zz.

A Memristor?

Quick, before you read this, what do you think is a "memristor"?

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Give up? It's a resistor with a "memory"!! I didn't know that either!

The existence of the memristor, short for 'memory resistor', was first suggested in 1971, but only now have researchers succeeded in creating a real, working example. They hope that the new components could revolutionize computing, promising an end to frustrating waits for your computer to boot up.

"A memristor is essentially a resistor with memory," explains Stan Williams of HP Labs in Palo Alto, California, who reports the memristor's creation in this week's Nature. "The actual resistance of the memristor changes depending on the amount of voltage and the time for which that voltage has been applied to the device."

The reference to the paper is:

D.B. Strukov et al., Nature 453, 80–83 (2008).

Fascinating!

Zz.

Shaken But Not Stirred

Although it isn't designed to detect earthquakes, many synchrotron facilities around the world, especially the latest generation facilities, can actually detect when an earthquake is occuring, some time halfway around the world. The recent earthquake in Southern Illinois that occured a couple of weeks ago was certainly felt in various parts of Chicago, and it was certainly detected by the Advanced Photon Source at Argonne.

The magnitude 5.2 earthquake that shook southern Illinois was “detected” by the beam position monitors that keep the electron beam on course in the APS particle accelerator (see the accompanying figure), but the machine continued to orbit electrons at nearly the speed of light with no noticeable adverse effects. Other monitors (x-ray beam position monitors) assured that x-ray beams illuminated experiment samples as small as molecules.

There are of course many steps in place to either make sure the beam continues to be stable, or in the worst scenario, that it gets dumped safely if it goes too far off course. The same thing is in place in many other facilities around the world, especially the LCLS being constructed at SLAC in the earthquake-prone California, which has an even more stringent beam operating parameters to produce its FEL.

I was told by someone working at the APS that they even detected the huge earthquake in the Indian Ocean from a few years ago that caused the massive and deadly tsunami. So this is one very sensitive machine with very precise diagnostics ability.

Zz.

Revamping Intro Physics Laboratory - Part 5

{{Note: If you wish to follow what has transpired so far in this series, here are Part 1, Part 2, Part 3, Part 3-Follow-up, Part 4, and Part 5}

This may be a bit misleading because it is not strictly a "laboratory exercise". In fact, I think it might be more suitable to be presented during class. Still, it involves the students doing something, so that fits in with the spirit of a laboratory.

This exercise has 2 parts to it. The first is in class where the students are asked to think about a situation, and write down what they think should occur. Then, they get to go out and test it themselves and observe the situation. They then come back and write down what they observe, and compare it to what they wrote earlier of what they THINK should occur. Finally, they get to explain their observations, especially if what they wrote earlier is different than what actually occurred.

So what is the exercise? Here goes...

You are in a stationary vehicle (a train, bus, or a large vehicle). You have a helium balloon attached at the end of a length of string, so the balloon floats freely (without being confined or rubbing against other objects), while you hold the other end of the string. The vehicle then accelerates forward. What happens to the balloon?

The whole point here is to see the effect of the acceleration in a vehicle (on earth) on an object that is less dense than air. You first give this in a class (or a lab) towards the end of the session, and then ask the students to write down what they think they will observe. They don't have to give you any reason, just what they expect to happen.

Then, give them some way to get a helium balloon. This shouldn't be too expensive, should it? Maybe they can get on a train to go downtown, let's say, with a group of their friends. That would be a great way to observe the balloon. Advice them that maybe it would be a good idea to write down there and then some notes on what they observe, and any relevant circumstances surrounding the observation (i.e. was the train packed? Did the balloon float freely? Were the windows open? Was the air conditioning blasting right at them? etc.) Then when they come back, they need to write down exactly what they observed, and compare that to what they wrote earlier before they did the "experiment".

I would then suggest that everyone discussion what they have done. Who predicted an observation that is consistent with what they actually observed? Who didn't see what they thought would happen? Why?

Now, it would be OK to tell the students before they did this that they need to make sure that there are no significant moving air, because that would ruin any effects of the acceleration. But I'm even tempted not to say that. This is because if there are students who did not consider this effect, then there could easily be a discussion on the nature of the 'experiment', and why the result that these students get doesn't quite tell you the effects of the acceleration. The "observation" isn't valid as far as finding the effect of the acceleration in a vehicle on the balloon, because other external factors have intruded into the observation. If these students acknowledged this extra factor, then they have been observant, and understands the non-validity of their observation. If the students did not realize this, then hopefully, other students will point it out during the discussion.

I'm hoping that during the discussion session is where the students start "argue" about the validity of each other's observation, such as the possibility that the wind or other factors might affect some other's observations. I'm also hoping that they might try to come up with some physics on what exactly is the most valid observation for a balloon in an accelerating vehicle that isn't affected by any other external factors. As the instructors, I would suggest you simply stay out of the way, and see how the students are thinking and reasoning their way through this. You can certainly offer some guidance, but the "thinking process" may take awhile, especially if there are many students who observe things differently from each other. They need to weed out which observation is "faulty" as far as answering the question at hand. Once they figured out the valid observation, then they need to figure out why it happened that way. It is the students that need to make their own self-discovery.

BTW, the valid observation in this case is that the balloon will tilt FORWARD, in the direction of the motion of the vehicle. This is, at first, counter-intuitive, because when a vehicle accelerates, objects tend to get pushed back in the opposite direction of motion. So the first inclination is to expect the balloon to tilt backwards. However, a floating balloon is less dense than the air surrounding it. So when the vehicle accelerates, the air surrounding the balloon gets pushed to the back of the vehicle more than the balloon, and thus displacing the balloon forward.

Strangely enough, it observation shouldn't be THAT unusual, because there's an identical situation to this that we are quite familiar with. If we apply Einstein's equivalence of gravity to acceleration, then technically, we are accelerating "upwards" at 9.8 m/s^2. Now try letting go of a helium balloon. It floats UP, in the direction of our "motion". It's the same effect we see in the accelerating vehicle. Yet, I'm sure, for many people, the observation of the balloon tilting forward is non-intuitive. If you are lucky enough to have students who actually argue using this point, then you have one heck of a student! I consider the ability to see the similarities of something "new" with something that they are familiar with as a major accomplishment. It is how we can describe many things that appear to be "different", yet share almost the same type of description or phenomena. I would suggest that if no students realize this, that you bring it up at the end of the discussion.

Zz.

Physicists Quantify the 'Coefficient of Inefficiency'

One of the skill one learns as a physicist is to tackle a problem systematically, and to quantify it, if possible, by making an effective, accurate model of the system. This problem doesn't have to be in physics. It can be anything. I mentioned earlier of someone who tried to find the most optimum way to load an airplane, simply because he became curious after observing how an airplane is typically boarded. Well, this is a similar problem.

Three physicists from the University of Vienna examines the efficiency of committees in making a decision in terms of the number of people that makes up the committee.

To understand why, Thurner and fellow physicists Peter Klimek and Rudolf Hanel turned to the British historian C Northcote Parkinson, who studied how the British Navy was once administered. Parkinson, who died in 1993, discovered a strong correlation between a committee’s ability to make a good decision, and its size. In particular, Parkinson found that committees with more than about 20 members are much more ineffectual at making decisions than smaller groups — something he dubbed the “coefficient of inefficiency”.

You can read the preprint of the paper from a link given in that article. It is a clever way to quantify and model this problem. Now if only people who form such committees would pay attention to it.

Zz.

Symposium Focuses on Energy Challenges

If you're in Chicago or near the Northwestern University campus, this might be something interesting to attend.

Steve Chu, who won the 1997 Nobel Prize in physics and is director of the Lawrence Berkeley National Laboratory of the U.S. Department of Energy, will deliver the keynote address at the Northwestern-Argonne Energy Symposium on Friday at Northwestern University.

The symposium, themed "Energy: The Challenge for the 21st Century," is free and open to the public. The program is from 8:30 a.m. to 5 p.m. in the Ryan Family Auditorium in the Technological Institute, 2145 Sheridan Rd., Evanston.

With the cost of gasoline here in the US rapidly approaching an average of $4 per gallon, this has become certainly a very hot topic.

Zz.

Just Because You Say It Is Based On Quantum Physics, Doesn't Make It So

So many pseudoscience are so damn quick to attach themselves to "quantum physics", as if they know what quantum physics is. I've already mentioned several instances of the bastardization of quantum mechanics by a few people who are using it to validate whatever it is that they are claiming. Well, count this one as one of them. It is the "ancient medical treatment" called Shirodhara.

I honestly don't care at all what people wish to do with their bodies. However, when they tried to justified it by saying some nonsense to the effect that it is verified by some aspects from physics, then that gets my goat.

Ayurveda, the primary health system in India, and western biomedicine, the primary system in North America, differ in their view of the body. "It needs to be emphasized that ayurveda is very much a science," Dr. Gupta stresses. "The foundation of ayurveda is based on quantum physics instead of molecules, cells and gross structure.

What the hell does that mean? And why is "molecules" different from quantum physics?

First of all, there's some inconsistencies here. This practice has been going on for "5,000 years". If it is true, how can it be "based on quantum physics", when quantum physics was only formulated in the early 20th century? Did someone from 5,000 years ago time-traveled to the time or Bohr, Einstein, Schrodinger, Heisenberg, etc. and got the knowledge about quantum physics and then got back to 5,000 years ago to form the Ayurveda medical treatment? Sure, I'll buy that!

OK, so maybe it isn't that. Does that mean that they realize that, like Chemistry, which came way before quantum physics, that what they are using can actually be "explained" by quantum physics? Really? Such as what? In Chemistry, many aspects of what is measured (as in QUANTITIVE MEASUREMENT), can be explained in terms of the formulation of quantum physics. The energy state of the hydrogen atom, the nature and strength of chemical bonds, the behavior of molecules, etc. In other words, a lot of things that were measured can be quantitatively derived from quantum mechanics.

Now I would bet you no such comparison has ever been made with this Ayurveda. Oh sure, they might bastardize various aspects of the superficial idea of "entanglement" (this seems to be a popular effect to be bastardized - refer to "The Secret"), but this is FAR from claiming that you have a foundation based on quantum physics.

What these crackpots do not realize is that to be able to say that something is based on quantum physics, one must DERIVE the effect for THAT PARTICULAR SYSTEM, using quantum physics. Start with the Hamiltonian, and use whatever means one has to drive both the QUALITATIVE AND QUANTITATIVE result that agrees with whatever it is one is trying to show an agreement of. One simply cannot use "superficial induction". Just because the phenomenon of entanglement has been shown to work in 2 photons does NOT mean that such phenomenon is valid for 2 apples! It isn't! But that is why these crackpots are doing.

I really don't know how the Edmonton Journal could have seriously published this with a straight face.

Zz.

The US Army Issues Polygraph To Soldiers In Afganistan and Iraq

Holy cow!

I didn't know about this until it was brought up by Bob Park in this week's column of What's New. So the US army thinks that they could improve security by using portable polygraphs.

The Defense Department says the portable device isn't perfect, but is accurate enough to save American lives by screening local police officers, interpreters and allied forces for access to U.S. military bases, and by helping narrow the list of suspects after a roadside bombing. The device has already been tried in Iraq and is expected to be deployed there as well. “We're not promising perfection — we've been very careful in that,” said Donald Krapohl, special assistant to the director at the Defense Academy for Credibility Assessment, the midwife for the new device. “What we are promising is that, if it's properly used, it will improve over what they are currently doing.”

This is astounding, considering that the NAS study has concluded that such devices are useless. They must be desperate enough to make use of voodoo science (a nod to Bob Park) to ensure safety over there. I think it would have been cheaper to simply hire a psychic, or train an army personnel in the art of reading tarot card.

As Bob Park said, these portable devices should work as well as the non-portable versions.

Zz.

Leaps of Faith

Here's someone who understands the importance of basic, theoretical physics research - Mike Lazaridis, founder and co-CEO of Research in Motion (i.e. make of the Blackberry).

That's one reason why, in 1999, Lazaridis donated $100 million of his nascent fortune to seed the institute. Another, he says, is "because people take theoretical physics for granted." No kidding. This world of equations and chalk dust is about as far away as you can get from the world of commerce. Why anyone would hand over such a massive amount of money—at the time, close to one-fifth of Lazaridis's net worth—to a collection of wild-haired math freaks is lost on most of the folks on Bay Street. Sure, Lazaridis knows that quarterly earnings are important. (In its most recent quarter, RIM posted a higher-than-expected profit of $412.5 million and shipped 2.2 million new BlackBerrys, the first time in the company's history that it broke through the two-million-mark in a quarter.) But he also knows that without the kind of work being done at Perimeter, chances are slim that someone will develop another world-beating technology like RIM's 60 or 80 years down the line.

Many of the CEO's of major technological and electronics companies are aware of this. The question is, do the general public and the politicians know this?

Zz.

Physics In Action at Theme Parks

Summer is almost here (at least here as in the northern hemisphere). With that, many theme parks are gearing for their busiest time of the year. Taking advantage of this are several schools and programs that try to marry the fun of theme park rides with physics lessons.

There are two recent examples to this. The first one is the Physics Day for area students at the Six Flags theme park in Largo.

Barnabas Adekanye, Irving Delco, Frailen Ramirez, Ludwin Romero and Johnny Wilks, all sophomores at Northwestern High School in Hyattsville who study engineering, were somewhere in the middle. They had brought a 28-page workbook of problems to solve. It was complicated stuff with a lot of formulas.

"Compare the change in potential energy to the gain in kinetic energy," went one question about the Mind Eraser. "Within experimental error, was energy conserved? Explain your answer."

Johnny, 15, had an easier explanation for what they were learning: "Like how the gravity and force relates with the loops and stuff."

The second example is a trip to Ceder Point by students from Windsor, Canada. I think it is a valid concern to look at it closely and see if the students are learning something, rather than simply using it as an excuse for a trip to a theme park. There has to be a conscious program to clearly demonstrate the physics principle to the students, and that the students actually got something. I think most of these programs try do that.

Zz.

Death For Phonons In High-Tc Superconductors?

This is a highly interesting and certainly provocative result.

Remember I posted a while back on the "kink" observed in the angle-resolved photoemission spectra (ARPES) on high-Tc superconductors? There have been a continuing debate since the kink was observed on the origin of this observation. Two leading candidates are the coupling of the charge carrier to a spin fluctuation mode, and a coupling to the phonons.

Now two separate theoretical papers have calculated the coupling to the phonon modes and have arrived at the conclusion that such coupling cannot account for the strength of the kink observed in ARPES spectra.

In recent years, despite mounting experimental evidence against it, some physicists have clung on to this interpretation. But now teams from Germany and the US have performed calculations to suggest that lattice vibrations in cuprates can at best account for just a small fraction of the materials’ superconducting behaviour.
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Manske’s team found that the theoretical energy–momentum relationship produced by these calculations did contain a kink — but about a three to five times smaller than the 2001 observations (Phys. Rev. Lett. 100 137001). This is bad news for physicists who have been hoping phonons can account for all of the behaviour of high-temperature superconductors. “It is embarrassing for people to admit they have worked on something for 20 years if it is not true,” jokes Manske.

Meanwhile, Steven Louie and colleagues at the Univerisity of California in Berkeley have come to a similar conclusion with the cuprate LaSrCuO4. From their calculations, the phonon contribution is almost an order of magnitude too small for the observed kink (Nature 452 975).

This could be rather devastating to the phonon picture. If this is true, the two new results still cannot account for the origin of superconductivity, but at least they have eliminated a red herring. Still, all this could be moot if an earlier report is true about the absence of any kind of "glue" in the mechanism for high-Tc superconductors.

So stay tune. The story is by no means over, and the fat lady hasn't even warmed her vocal cords yet.

Non Sequitur

Thanks to Jim McNamara at PF for pointing this out. I thought it was a hilarious cartoon.

I don't know if that is a permanent link, unfortunately, for this cartoon.

Update: Thanks to Tom for the permanent url to the cartoon.

Zz.

Bubble Fusion Fiasco Just Won't Go Away

Reported in the new edition of Nature (23 April 2008), it appears that Purdue University has sent its final report to the Office of Naval Research that funded Taleyarkhan's work on the so-called bubble fusion that is being questioined. But that's not it. He himself plans to contact the ONR directly to dispute the report (which implies that the report isn't favorable towards him). And, get this, he also plans on suing certain people!

The engineer is also pursuing a defamation lawsuit, filed last month in Tippecanoe County in Indiana against scientists who questioned his claims of bubble fusion. The defendants include Purdue faculty members named in Nature articles, which helped trigger an institutional review. “The complaint filed is to clear up my reputation,” Taleyarkhan says.

Peachy!

Zz.

Can Buckyballs Make Flash Memory More Efficient?

The flash memory that is now very common in many devices may get a big boost if this report is correct. It seems that using buckyballs (C60 fullerenes) could operate at a lower voltage (link may be accessible only for a limited time for non subscribers) and thus, make the flash memory devices more efficient.

“We’re the first ones trying to borrow molecular electronics concepts and put them into non-volatile memory,” says electrical engineer Tuo-Hung Hou of Cornell University in Ithaca, New York, who led the research (T.-H. Hou et al. Appl. Phys. Lett. 92, 153109; 2008).

This is also another example of a possible wide-ranging application of physics.

Zz.

Towards A No-Loophole Bell-Type Experiment?

Looks like we are well on our way to achieving that and nailing the coffin shut on Local Realism..... or are we?

The paper published last week in PRL[1] seems to point to the possibility of a loophole-free Bell experiment. While entanglement experiments with photons have closed down the locality loophole, and experiments with "particles" such as protons, neutrons, etc... have closed down the detection loophole, no experiments have managed to close both of them simultaneously.

This experiment with Yb+ atoms is well on its way to getting there. While they have certainly closed the detection loophole, they have reduced the possibility of the locality loophole by separating the atoms by 1 m (previously, the spatial separation was of the order of microns). So this is a tremendous improvement.

Eventually, it will be convincing enough, if it isn't already.

Zz.

[1] D.N. Matsukevich et al., PRL v.100, p.150404 (2008).

Phenomenology of the Normal State In-Plane Transport Properties of High-Tc Cuprates

I always like it when authors upload their published papers. It gives those who do not have access to the various journals a chance to get a copy of a peer-reviewed, published papers, especially if they're in respectable journals.

This paper is more of a review of the current understanding of the anisotropic nature of the in-plane transport of the cuprate superconductors. The cuprate superconductors are well-known to have highly 2D nature in its charge transport, most probably due to the layered nature of the compound. It is believed that the transport occurs in the copper oxide planes, especially since the resistivity perpendicular to the planes is roughly 3 to 4 orders of magnitude higher. However, even within the copper oxide plane itself, there is a considerable anisotropy in the transport direction, as seen in various measurements.

The paper has a very good review of our state of knowledge on this issue so far, and also a good background info regarding the cuprates superconductor for those who need to get up to speed.

Zz.

Teaching Superfluidity at the Introductory Level

I've only glanced through briefly this preprint, but from what I can see, it might provide a useful intro to superfluidity to undergraduate students, and even to those with some physics background. This isn't a topic that is dealt with in extensive details at the modern physics intro level, so it might fill a gap (no pun intended).

If you have read this and have comments about it, I'd like to hear them, especially if my impression of it isn't accurate.

Zz.

Who or What is RVB?

In an earlier entry related to the "No glue for cuprate superconductors", I mentioned that Phil Anderson might be right after all since this could be consistent with what he has been pushing all along. Of course, what I had in mind was his Resonating Valence Bonds (RVB) theory as applied to the cuprate superconductors. I believe he has argued for the non-conventional (as in no boson coupling) origin of the superconductivity in the cuprates. So this result is certainly in favor of that picture.

In any case, not sure if it was deliberate or terrific timing, there is a start of at least a couple of columns on RVB in Physics Today. The first article appeared in the April 2008 issue, which you can read for free even if you're not an APS member. In this article, he describes basically the history of RVB theory. But I think I am more interested in the teaser that he gave at the very end, which is supposed to described "... the rise and fall and rise again of RVB's relevance to high Tc and other superconductors..."

Now THAT, is a physics cliff-hanger!

:)

Zz.

A Case Study of Gender Bias

OK, this thing has the potential of becoming a rather big news especially when the popular media picks it up or the a coverage in Nature (whichever comes first). This arXiv preprint titled "A Case Study of Gender Bias at the Postdoctoral Level in Physics, and its Resulting Impact on the Academic Career Advancement of Females" is getting quite a bit of legs. You might want to also look at the trackback links to read more about it.

I'm not endorsing or disputing the report, simply pointing it out since the cat, obviously, is out of the bag. I'm guessing there's more to come on this.

Zz.

Looking Into Nuclear Power

Two different articles appeared almost at the same time discussing the use of nuclear power to generate electricity. So you might want to read them here and here.

I will fully admit that I am very much in favor of nuclear power. As with many aspects of physics/science policy in which ignorance and lack of knowledge have interfered with the decision-making process, nuclear power has suffered from the same fate. Both article addressed many of the issues involved currently when one talks about nuclear power.

Zz.

Saving Energy While Driving

So I don't remember which TV public service announcement that I heard this from. I think it was on one of the cable channels that was advising how you can make NY City more "green". In any case, that isn't relevant. What it did say was that you can save gas if you drive with your windows up, especially at high speed.

Of course, with everything being the equal, this is true. If you drive with your windows down, you create more drag, or air resistance, for your vehicle. Thus, you burn more fuel as you drive, especially when you're driving very fast.

HOWEVER (somehow, I think you were expecting that, weren't you? :)), let's consider the situation here of when you usually drive with your windows down. It is typically in the summer, or when the weather is warm. So, if you roll up your windows, you inevitably crank up the air-conditioning! So now, you've reduced air drag on your vehicles, but you're using up additional fuel due to the air conditioning.

So which one uses up more fuel - driving with the windows down but no air conditioning, or driving with the windows up but with air conditioning? I haven't looked into the calculations of how much power is used is a typical car air-conditioner, and I haven't looked into it yet on the amount of drag created when a car drives around at, say, 60 mph (yes, we still use mph here in the US). Does anyone have some rough estimates on what these might be? Off the top of my head, I would think that driving with the windows down instead of using air conditioning might be more energy efficient than the other alternative.

Of course, driving with the windows up and not using air conditioning is a no-brainer better option. But the PSA didn't say that. All they said was to drive with the windows up to save fuel. That is not the complete story.

Zz.

Physics for Sports Nuts

Highly unusual for the Wall Street Journal to review a book about the physics of sports, but here it is. The reviewed "Why a Curveball Curves: The Incredible Science of Sports", which was compiled by the editors of Popular Mechanics. To quote the reviewer's own words:

This book is quite possibly every sports nerd's dream.

So don't feel self-conscious if you go out and buy it at a bookstore near you. :)

Zz.