Unfortunate Acronym

First of all, this is not an attempt at being politically correct. I'm not criticising anything or asking for something to change. It is just that I find it a bit "amusing" some time, and wonder if anyone else spotted it, especially those who came up with it.

Often people come up with very cute acronym for many things. I can think of WIMP and MACHO, etc. in physics. These are catchy acronym that many people, including the general public, catch on. However, sometime, they come up with rather unfortunate acronym. I came across this one several years ago, and somehow, after reading an article this morning, it popped up again. The acronym is "FFAG", for Fixed-Field Alternating Gradient accelerator. I'm sure that most people reading this can guess what is unfortunate about this acronym (remove one of the "F"s and it becomes a short form of a derogatory word).

Of course, the first thing that came to mind is if the people who came up with the acronym actually realized this. The second thing that came to mind is on how this acronym is pronounced. Usually, acronym that can form a "name" that can be pronounced is usually refered to by that pronounciation. One would refer to WIMP as "wimp", not "W - I - M - P". So do people refer to "FFAG" as "F - F - A - G" or "F-fag"? I don't know about you, but I would feel rather uncomfortable to say the latter, even if nothing bad is intended.

I haven't had the opportunity yet to be in the circle of people that actually discussed this subject area yet, so I'm a bit curious on their view on this, or how they go about mentioning this word. Of course, I certainly wouldn't discount the fact that most of the people who do use this acronym aren't even aware of this angle, especially since there are many non-native English speakers involved in this field of study and the social/cultural connotation involved in that word doesn't mean anything to them.

Have you come across any similar acronym in physics/science that has the same unfortunate connotation?

Zz.

ScienceDebate Announces Shift to Oregon

The initiative to hold a Science Debate among the US Presidential candidates is not going well. The planned debate to be held in Philadelphia has been canceled, and the organizers hope to schedule another one later in Oregon.

At this stage, I'm skeptical that it will occur. As the article stated, the candidates at this point are "well-defined" and don't need any more publicity. And science isn't anywhere near the important factor that the general public would consider in making their decisions on who to vote for.

Zz.

Thousands Showed Up for CERN's Open House

Fifty thousand, to be exact. It was the last time the public will get to see many parts of the facility before they are closed down for the expected start-up in July. I suppose all the brouhaha about CERN and the black hole creation created even more publicity and even more interest in it.

And now, ladies and gentlemen, start your engine!

Zz.

'The Physics of NASCAR' Lecture

I mentioned earlier on the physics involved in a NASCAR race. Now there is an announcement of a lecture on the Physics of NASCAR tomorrow (Monday, April 7, 2008) at the University of North Carolina - Charlotte. It will be given by Diandra Leslie-Pelecky, the author of "The Physics of NASCAR".

If you get to attend this, could you write something about it?

Zz.

Follow-Up To The LHC Lawsuit

I was reading Bob Park's entry (April 4, 2008) of this LHC lawsuit yesterday, and it brought back memories of the almost-identical issue being faced when RHIC was about to start up. It was such a brouhaha that even Comedy Central covered it! :)

It is worthwhile to note of the in-depth study that was done at that time to dispel the myth that RHIC would create not only black holes in its collisions, but a catastrophic one. And unlike the joker who filed that lawsuit, this scenario was brought up not by an ignorant individual, but rather by a few physicists themselves. So certainly it warranted a careful consideration.

However, there were two different issues involved here. The first was the careful study of the claims made within the scenario, i.e. can there be a catastrophic creation of blackholes that could spell disaster. This was easily dispelled because of the existence of the moon (you'll have to read the full report). The second one was more difficult to explain to the general public. In many instances in physics, we see different phenomena that share the same mathematical description or formulation. The similarities of the mathematics from some aspect of condensed matter physics and elementary particle physics is one example. This is again what happened in a RHIC blackhole scenario. The problem here is that once that comparison got out, it caught fire among the media and the general public, who weren't able to know the significance of such a comparison. All they see is the "headlines" of blackholes being created, and that's that.

Again, this is where, if one doesn't have the necessary knowledge to decipher the information, one can be easily mislead by news reports. Sometime, it is the fault of scientists themselves for sensationalizing the issue (example: quantum teleportation, and anything Michio Kaku has written in his latest pop-science book). The public does not have the understanding and the formalism in mind when they read these things, unlike physicists. All they can do is associate what they read with what they know, and what they know come mostly from the media, TV, movies, etc. So it should not be a surprise that they can't tell the different between the "quantum teleportation" as a demonstration of quantum entanglement, and the teleportation they saw in Star Trek. When you use the same word, you should expect the pedestrian meaning of it to dominate, where it is accurate or not.

Zz.

Addendum: Looks like the Editorial in the NY Times has it right.

More than once over the years we have felt as if we were transported to another universe listening to lawyers and judges wield the complexities and arcana of their trade. It would be fun to watch them struggle with theoretical physics. But if the courts have any sense, they will drop this suit into the nearest black hole.

More CP Violation

On the heels of the KEK report that I mentioned earlier, here comes the analysis of the data from the Tevatron at Fermilab that point to the same conclusion.

The amount of CP violation observed in experiments (and enshrined in the standard model), however, is far too little to explain why matter should have prevailed in its ancient war with antimatter. To get a clean look at CP symmetry, DZero and its sibling detector, CDF, focus on the BS, which consists of a bottom quark and a strange antiquark. (Quarks are components of protons and neutrons.) Working independently, the two detectors both found an extra dose of CP violation beyond what the standard model predicts.

Neither result on its own was very convincing, so a team of Italian researchers combined the data, similar to the way medical researchers cull information from independent clinical trials, to look for rare side effects. Together, the data make it 99.7 percent likely that the discrepancy is real, not due to chance, says physicist Luca Silvestrini of the National Institute for Nuclear Physics in Rome, who took part in the study submitted to Physical Review Letters.

Looks like both the CDF and D0 got similar things, which is always good.

Zz.

Q&A With Bill Foster

As the newest member of the US Congress, and the 3rd physicists in Congress, Bill Foster has a short Q&A session with Nature.

Zz.

Feynman and the Music of Physics

Symmetry Breaking has an interesting, short article on Feynman and his bongo-playing. If you've read any of Feynman's biography (Glick's "Genius" is a good one), you'll know that he doesn't like any kind of "structured" music, but rather the more primitive, tribal rhythm.

So here's the video of Richard Feynman during one of his finest hours. :)



Zz.

High-Tc Superconductors Are Very Kinky

In trying to decipher the mysteries of the mechanism that causes superconductivity in high-Tc superconductors (HTS), we have to characterize and understand the many-body interactions that influence the behavior of the charge carriers in these material. In a standard Fermi Liquid theory, these charge carriers are called quasiparticles, and their behavior are described by what is known as the spectral function A(k,E) (i.e. the imaginary part of the single-particle Green's function). The interactions that influence the behavior of these quasiparticles are quantified in the spectral function via the complex self-energy term Σ. The real part of the Σ shows how these collective interactions influences the dispersion relations/band structure of the material (i.e. the E vs. k curves), while the imaginary part of Σ indicates the scattering rate or lifetime of the quasiparticles. For an idealized metal having a non-interacting free-electron gas, the self-energy term is zero. This means that there's no deviation from the non-interacting electronic band structure/dispersion (ReΣ=0) and it has zero scattering rate/infinite lifetime (ImΣ=0).

So if one can actually measure this A(k,E), one can gain a lot of insight into the interactions that influence the behavior of the quasiparticles that are responsible for superconductivity in high-Tc superconductors. One of the ways to make a direct measurement of the spectral function (at least the occupied side of the band) is by using the angle-resolved photoemission spectroscopy (ARPES) technique. In an earlier post, I have highlighted a review of this powerful technique and how it can directly measure A(k,E). This technique has produced very clear signature of the various interactions in a typical metal such as Be[1] and Mo[2], showing very clearly the electron-electron interaction, the electron-phonon interaction, and electron-impurity interaction, all based on the self-energy obtained from ARPES measurement. The parameters obtained from the results, such as the electron-phonon coupling strength, all agree with existing theoretical predictions and previous measurements. So we know that such a technique works.

Because of that, ARPES has been extensively used in the study of HTS. This family of material is high suitable for this technique because of its layered, 2D structure. Furthermore, HTS compounds such as the BSCCO family are easily cleaved in situ along these 2D planes, exposing a pristine surface perfect for photoemission studies. A major progress in ARPES technique came in 1999 whereby not only the energy distribution curve (EDC) at a particular momentum are collected, but also the momentum distribution curve (MDC) at a particular energy can also be obtained simultaneously! This resulted in the collection of a 2D raw data of energy distribution and momentum distribution of the photoelectrons within an energy and momentum window[3]. What is essentially obtained is the dispersion curve. When this technique was done on the BSCCO family, a distinctive feature of a "kink" in the dispersion with an energy scale of around 50 meV was clearly observed[4]. This kink is the deviation of dispersion curve from the non-interacting dispersion, which signifies a coupling to some bosonic mode. By 2001, the race was on to analyze the nature of this kink to see if one can identify this "bosonic mode" that affects the electronic dispersion. This bosonic mode might be the "glue" that holds the Cooper pairs together in the formation of superconductivity.


[Figure shows the "kink", i.e. the deviation from the non-interacting dispersion (Campuzano et al. in The Physics of Superconductors, Vol. II, ed. K. H Bennemann and J. B. Ketterson (Springer, New York, 2004), p. 167-273., or at http://arxiv.org/abs/cond-mat/0209476]


There were three important papers that were published in 2001 that were the first to analyze the origin and nature of this kink[5,6,7]. Two different groups arrive at roughly the same conclusion - that the kink seems to indicate a coupling to a magnetic (spin) bosonic mode[5,6], while the Stanford group[7] proposed the phonon as the origin of the kink. There have been many publications since then arguing for various scenario for the origin of this kink and until today, there is no overwhelming consensus for either the magnetic, although my quick review of this matter seems to indicate that there are more publications related to ARPES experiment in favor of the magnetic channel [8,9]. Still, the phonon picture has many strong advocates and the issue isn't settled even to this date.

But that is not the end of the story. It appears that the high-Tc cuprate familyis even kinkier than first thought. There seems to be, in addition to the low energy kink (now regarded to be between 50 to 70 meV scale), a higher energy kink in the dispersion has been discovered. It was reported, in succession within the span of a couple of weeks, by 2 papers in Phys. Rev. Lett.[10,11]. This new kink occurs at an energy scale of around 340 meV, so it is considerably larger than the low energy kink. The latter concluded that this new high energy kink is consistent with coupling to the magnetic (spin excitation) mode.

Since then, there have been even more reports on high energy kink[12], and this one is even at a different energy scale (115 and 150 meV) and the authors are suggesting that these may be due to neither spin fluctuation nor phonon modes.

Moral of the story: the high-Tc family of material is very kinky, and that the study on the origin of these kinks could hold a vital clue on the mechanism of superconductivity in these materials. However, the issue is highly complicated, especially when new discoveries are continually being made as one tries to solve the old ones. Whether these kinks are due to coupling to the magnetic mode, phonon modes, or neither, remains to be seen. A lot more work is still to be done.

Zz.

Edit (04/10/08): A new preprint on arXiv[13] has appeared that studied the phonon mode in La doped Bi-cuprate compound. The result supports the electron-phonon coupling as the source of the kink in the cuprate superconductor.

Edit (06/10/08): A new preprint on arXiv[14] has studied the phonon dispersion in on of the Bi cuprate family using inelastic X-ray scattering. They found a significant phonon softening that's consistent with the same energy and momentum scale as the kink observed in the ARPES result. So this argues for the phonon origin of the kink.

Edit (07/02/08): This is getting to be quite interesting. A new PRL paper[15] has just been published, arguing that the high energy kink is more of an artifact of the MDC analysis, and that the EDC spectra provides a more accurate information about the band dispersion in high-Tc superconductors. So this certainly calls into question the conclusion made in previous papers on this high-energy kink.

Edit (12/22/08): A new theoretical analysis using parameters from the inelastic neutron scattering experiment has produced a model that can explain all the ARPES results[16]. It points to the incommensurate spin excitation as the dominant scattering mechanism.

Edit (02/26/09): A new manuscript has just appeared that compares the high energy kinks between the electron-doped cuprate with the hole-doped cuprates[17].

Edit (04/14/09): A manuscript has appeared that discussed the possibility that the high energy kink in the Bi-cuprates might be due to an artifact of the matrix element. The calculation produced showed that it isn't, and that this kink points to the coupling of the quasiparticles to the electronic mode [18].

Edit (06/16/09): A manuscript appeared today calculating the phonon contribution to the kink[19]. They concluded that phonons only contribute ~10% to the kink, while non-phonon sources contribute to the other 90%.

Edit (08/05/09): A PRL paper on ARPES measurement of single layer, bilayer, and trilayer Tl-family of high-Tc cuprate[20] shows that the kink has a momentum dependence as one changes the number of CuO planes per unit cell. The authors claim that this is not consistent with magnetic coupling scenario, and thus, seems to point to the electron-phonon coupling as the origin of the band renormalization (i.e. the kink).

Edit (02/02/10): A preprint on arXiv has reported a high-resolution, laser-based ARPES measurement on heavily overdoped (Bi,Pb)2Sr2CuO6. The report claims that the 70 meV kink along the nodal direction is due to coupling to multiple phonon modes[21].

Edit (02/15/10): 2 new reports on a new kink in the band dispersion of Bi2212. This kink is ~8 meV below the gap energy and may be tied to the optical phonon mode[22,23]

Edit (05/24/10): A new theoretical analysis of the low and high energy kink in the cuprates have revealed that these kinks can be reproduced by phonons using the extended Eliasberg theory [24]

Edit (01/10/11): An analysis of the low energy kink has attributed it to an in-plane acoustic phonon branch[25].

Zz.

[1] S. LaShell et al. Phys. Rev. Lett. v.61, p.2371 (2000).
[2] T. Valla et al., Phys. Rev. Lett. v.83,p.2085 (1999).
[3] T. Valla et al., Science v.285, p.2110 (1999).
[4] P.V. Bogdanov et al., Phys. Rev. Lett. v.85, p.2581 (2000).
[5] P.D. Johnson et al., Phys. Rev. Lett. v.87, p.177007 (2001).
[6] A. Kaminski et al., Phys. Rev. Lett. v.86, p.1070 (2001).
[7] A. Lanzara et al., Nature v.412, p.510 (2001).
[8] A.A. Kordyuk et al., Phys. Rev. Lett. v.92, p.257006 (2004); A.A. Kordyuk et al., Phys. Rev. Lett. v.97, p.017002 (2006).
[9] A. Macridin et al., Phys. Rev. Lett. v.99, p.237001 (2007).
[10] B.P. Xie et al., Phys. Rev. Lett. v.98, p.147001 (2007).
[11] T. Valla et al., Phys. Rev. Lett. v.98, p.167003 (2007).
[12] http://arxiv.org/abs/0711.1706.
[13] http://arxiv.org/abs/0804.1372.
[14] http://arxiv.org/abs/0804.1372.
[15] W. Zhang et al., Phys. Rev. lett. v.101, p.017002 (2008).
[16] T. Dahm et al., http://arxiv.org/abs/0812.3860.
[17] M. Ikeda et al., http://arxiv.org/abs/0902.4280
[18] S. Basak et al., http://arxiv.org/abs/0904.1749
[19] E. Schachinger et al., http://arxiv.org/abs/0906.2627.
[20] W.S. Lee, Phys. Rev. Lett. v.103, p.067003 (2009).
[21] L. Zhao et al. http://arxiv.org/abs/1002.0120
[22] J.D. Rameau et al. Phys. Rev. B v.80, p.184513 (2009) http://arxiv.org/abs/1002.1990
[23] I.M. Vishik et al., Phys. Rev. Lett. v.104, p.207002 (2010) http://arxiv.org/abs/1002.2630
[24] E.A. Mazur http://arxiv.org/abs/1005.3930
[25] S. Johnston et al., http://arxiv.org/abs/1101.1302

Statistical Evidence Consistent With Performance-Enhancing Drugs in Professional Baseball

It seems that the use of statistical analysis has been quite prominent in the controversy surrounding the use of performance-enhancing drugs in baseball. Roger Clemens had a team trying to use such statistics in his favor, but it has now been discredited by a team of Ivy League professors.

Now comes even more support for the Mitchell Report. A team from Boston University has analyzed the statistics in baseball, and applied the power law density distribution from complex systems. They arrived at the conclusion written in the title.

So far, the scientific and statistical aspects of this controversy do not support the innocence of the players involved.

Zz.

Bush to Science: "Let's be friends"

Holy Cow! This must be an April Fools joke!

Bush also plans to relax his stem cell policy. Although he has twice blocked congressional bills that would have expanded federal research on embryonic stem cells (ScienceNOW, 20 June 2007), he said today that such vetoes were a mistake. Bush said he now regrets having placed more value on a destined-to-be-discarded embryo than on a 30-year-old mother with multiple sclerosis--not to mention Michael J. Fox. "Why wait for a new president?" said Bush. "Let's get these embryos into the hands of scientists who can use them for good."

In a final concession, Bush promised to be a better steward of the planet. "I haven't always been clear about the threat global warming poses," he said. "In retrospect, having oil industry lobbyists edit our climate reports was probably a bad idea." He also admitted that initiatives such as "Healthy Forests" and "Clear Skies" had led to excess logging and air pollution, respectively. To make amends, he has appointed former rival and Nobel laureate Al Gore to head his new conservation initiative, which calls for mandatory cuts on greenhouse gas emissions and rigorous protection for species classified as threatened or endangered. "We're calling it 'Pristine Planet,' " said Bush. "And this time we mean it."

I would say that that last part kinda gave it away, really. Who would believe such a thing? :)

Zz.

Sea Perch is a Fun, Hands-On Approach to Teaching Science

This Physics Today article highlights a project called Sea Perch, a hands-on approach to getting schoolchildren interested in science and technology.

For 10 weeks, Anderson will be showing the 10 students who stay after school for a couple of hours how to assemble their ROVs from kits consisting of such everyday items as PVC pipe and electrical tape. When the students are finished, they'll get to take the electrically powered vehicles to a test tank at the US Naval Academy, where they'll maneuver them by remote control. Throughout the process, the students will learn about buoyancy, displacement, and other physics principles through simple, well-crafted experiments. They also learn how to operate an electric drill and a soldering iron. Best of all, they're having fun doing it.

This is similar to my philosophy on the revamping of the undergraduate intro physics labs. Don't give some rudimentary exercise for them to do. Give them a TASK in which they have to build something or figure out something to accomplish that task. Along the way, they will need to learn certain techniques, or learn certain reason why something should be done in a certain way, just like the kids on this program:

As the children await their turn with the drill, they tested Archimedes' principle by fashioning crude model ships out of aluminum foil. Their goal was to see how many marbles they could load into the makeshift hull before it sank from the weight. By maximizing the length and width of their boats, they learned, they could increase the marble count. They recorded observations in laboratory logbooks. Asked by Anderson to explain how repeated trials are necessary in science, one savvy student explained the importance of changing a single variable at a time.

Reviewing what they had learned that day, Charlie Youngman observed, "the more weight, the more water it displaces," while Matt Rinaldi explained that if a vessel has "solid walls," it's less likely to sink. For R. J. Neal, the biggest lesson was "safety first; always use goggles when drilling."

If these are the lessons that the students learned from the program, then I would say that in my eyes, it has accomplished what many undergraduate intro physics labs have failed to accomplish or reinforce into the students. The ability to know the relationship between what we manipulate and what the corresponding outcome is one of the most important aspect of science, and certainly, experimental science. The students in this program obviously are getting that without even having to be taught of it. Why can't we do the same thing with the undergraduate intro physics labs?

Zz.

Moore Looks Beyond the Law

Gordon Moore, the legendary Intel cofounder, and the originator of the "Moore's Law" for the semiconductor industry, sat down with the editors of Physics Today for a very insightful interview. Read about his contribution to various scientific projects through his foundation.

Zz.

Traffic Jams Happen, Get Used to It

I've heard about this research study, but I didn't pay that much attention to it until I saw that they had a video of this effect that was rather neat. It also confirms what I had suspected for a while.

The study was done by a group of Japanese scientists/mathematicians about traffic jams that happened without any bottleneck[1]. In other words, there's no obvious obstacles, such as an on-ramp, or a constrictions, etc. that would be obvious causes for a traffic jam. All they did was increase the traffic density, and at some point, there's some "critical density" in which traffic jams simply occurs because people just don't all drive at the same speed.

What is need is that you can actually this taking place in the video that they have included. I've always suspected this. I drive roughly 31 miles each way to work every day. I sometime get stuck in a couple of slow spots where traffic either slows down or stopped for periods of time. Yet, as you you drive some more, you speed back up again as if nothing has happened, and you don't see any reason why the traffic slowed down. I tend to blame it on slow cars in the left lane, but I had no proof that was the usual cause. Now, I have some evidence to back my haunch! :)

Zz.

[1] Y. Sugiyama et al., New Journal of Physics v.10 p.033001 (2008).

Time-Keeping Milestone

There are a couple of interesting reports in the latest issue of Science this week (Science 28 March 2008). Two papers have made the most accurate measurement of time-keeping to date. One uses the optical transition from ions[1], while the other uses neutral atoms[2]. They produced a time accuracy of up to 10^-17 and 10^-16 second, respectively, which is significantly more accurate than the Cs atomic clock.

However, as pointed out in the Perspective by Daniel Kleppner in the same issue, with an error budget that includes perturbation of the order of 10^-18 s, such precision now has to consider the effects of General Relativity.

When precision is pushed to new levels, ever more subtle effects must be taken into account. For instance, the error budget includes a small contribution, 1 mult 10-18, due to an uncertainty in the gravitational potential of the two clocks. This corresponds to a difference in their altitudes of 1 cm. This heralds one of the most interesting aspects of time keeping with optical clocks: The effects of general relativity that mix time with gravity are starting to approach a point that will require rethinking the basic concept of "keeping time."

The "two clocks" referred here are the two ion clocks used in the T. Rosenband et al. experiments - Al+ ion and Hg+ ion clocks. Having clocks that are now sensitive enough to detect effects of GR would certainly open up a whole possibility of testing GR even more.

Zz.

[1] T. Rosenband et al., Science v.319, p.1808 (2008).
[2] A. D. Ludlow et al., Science v.319, p.1805 (2008).

Gyroball - A "Nothing Ball"?

The controversy surrounding the existence of a "gyroball" in the sports of baseball continues. Recall that I reported on this a while ago of the skepticism that such a ball can be thrown. Now there's a new follow up to this issue where even more people are simply questioning why this is such a big deal.

Adair said it actually mimics a pitch in cricket that "probably goes back 100 years," its odd-duck spin more useful in that sport because the ball is bounced to the batsman. "It had various names," Adair said. "The 'googly' and the 'Chinaman,' because a British bowler of Chinese extraction threw it.'

"Properly thrown through the air, the gyroball does nothing. It's a 'nothing ball!'"

Or as University of Illinois physics professor Alan Nathan amended, "A 'qualified nothing ball.' Because if the batter is expecting a 'something ball' [with a break or a dip], that makes a 'nothing ball' effective."

Sort of a reverse psychology? :)

I wish they just play ball!

Zz.

Lawsuit: Huge Atom Smasher Could Destroy World

This news has been making the rounds around various blogs and news wires. A couple of wackos have decided to file a lawsuit against the US Dept. of Energy (DOE) and CERN to stop them from building the Large Hadron Collider (LHC) at CERN.

I debated on whether I want to dignify this stupidity by reporting it on here. But then again, it is going to be reported anyway. This news report has some brief description of the background of the yoohoos that filed the lawsuit.

Not included among the documents is Wagner's own indictment last month on identity-theft charges tied to an ongoing legal battle over a botanical garden on the Big Island of Hawaii, but you can read about that here.

Most physicists say Wagner's worries are unfounded. Micro black holes would evaporate nearly instantly instead of combining to form larger ones, they say, and the "strangelet" particles he frets would freeze the world would in fact fall apart quickly.

Wagner's own background is a bit fuzzy. He claims to have minored in physics at U.C. Berkeley, gone to law school, taught elementary-school science and worked in nuclear medicine at health facilities — but he doesn't appear to have an advanced degree in science.

Sancho's qualifications are even murkier, but the lawsuit identifies him as a Spanish citizen residing in the U.S., even if his presence makes the entire case a bit, um, quixotic.

And before someone accuse me of simply trying to attack the credibility of the wackos rather than address the "physics", let me point one very glaring and important observation here. There are already extremely energetic particles colliding with other particles in our universe. For example, the recent Auger Observatory results studied the origin of the these cosmic particles, that have energies in the 100's of TeV, something that CERN cannot even come close to. These particles have been around for million (even billions) of years, and have made gazillions of collisions. If such high energy collisions can create blackholes, we would have been swallowed and destroy by them already by now. Hello? Is this not obvious?

It looks like the crackpots are now getting a bit more daring. But now, rather than just being an internet nuisance, they are now being a pain-in-the-rear-end with their frivolous lawsuits. So anyone who thinks that these crackpots are just a "harmless" bunch of losers, think again. They're still losers, but they're definitely not always harmless.

Zz.

Giant Magnetoresistance

The 2007 Nobel Prize in Physics was awarded to Albert Fert and Peter Grünberg for the discovery of the Giant Magnetoresistance, as reported earlier. I had also given a good link that explains what GMR is. Still, one can never have too many good explanations of what it is, so here's another one, this time, it's an article from Physics Central.

This is actually quite appropriate because it is another example on how basic research in strongly-correlated electron systems can produce something that becomes important in our daily lives. It is why basic research is important. One would hope that this message gets across to those people making funding decisions.

Zz.

Webcast: Nobel Laureate to lecture on "Blind Chance or Intelligent Design: The Need for Basic Research," April 8, 2008

Here is the announcement for the next series of Honeywell-Nobel Initiative lecture series:

Some scientific advances, such as the discoveries of X-rays and penicillin were stumbled upon through serendipity. Others, like streptomycin and nuclear reactors, resulted from targeted and specific research. Honeywell will be presenting a lecture and Webcast by Nobel Laureate Dr. Sheldon Glashow on “Blind Chance or Intelligent Design: The Need for Basic Research" at 9:00AM on April 9, 2008 in Beijing (9:00PM pm April 8, 2008 in Eastern Time).

Dr. Glashow’s many research accomplishments in theoretical physics include his prediction of the charmed quark (for which he was awarded the Oppenheimer Medal) and his seminal contributions to the unified theory of weak and electromagnetic interactions (for which he shared the 1979 Nobel Prize in Physics).

For the past quarter century, while he has continued his fundamental researches in particle physics and cosmology, Dr. Glashow has also focused on stimulating interest in science among high-school students and encouraging scientific literacy among non-science students at the university level.

Dr. Glashow will be delivering a lecture to students at Beihang University, Beijing, China on April 9. A live Webcast of his remarks, as well as related content, will be available for viewing from Honeywell Science.

The video of the recent lecture on Cosmic Background Radiation by George Smoot is now available online.



Zz.

Under Control: Keeping the LHC Beams on Track

While people do have some idea of the size and the complexity of the LHC, most do not have a good 'scale' of the issues involved here. There are some astounding issues and problems that they have to deal with. Keeping the LHC beam under control, and what to do when it veers off course is a major issue.

This article tries to impart some idea on the control and contingency issues of the LHC beam. For example:

The complexity means that repairs of any damaged equipment will take a long time. For example, it will take about 30 days to change a superconducting magnet. Then there is the question of damage if systems go wrong. The energy stored in the beams and magnets is more than twice the levels of other machines. That accumulated in the beam could, for example, melt 500 kg of copper. All of this means that the LHC machine must be protected at all costs. If an incident occurs during operation, it is critical that it is possible to determine what has happened and trace the cause. Moreover, operation should not resume if the machine is not back in a good working state.

So this is not case where you can just simply pull the switch if something goes wrong. They have to make sure they dump the beam properly without causing damage to all the components along the ring.

This is, of course, a common issue at large particle accelerator facilities, including the Tevatron. I am still at awed at some of the things they are able to do, and at the scale that they are doing in. I some time wish the most of the general public has some clue on the level of complexity and the accomplishments at just being able to run such an experiment.

Zz.