Friday, April 30, 2010

Laser - The First 50 Years, And The Next 50 Years

A perspective on the first 50 years of the laser, and what we might possibly look forward to for the next 50 years.


Wednesday, April 28, 2010

Ignitor to Challenge ITER

Italy and Russia are poised to build a new fusion facility called Ignitor.

Russia and Italy announced on Monday that they will collaborate to build a new tokamak fusion reactor called Ignitor. Following talks between Italian Prime Minister Silvio Berlusconi and his Russian counterpart Vladimir Putin, other ministers signed a memorandum of understanding to work together on building the Italian-designed device on Russian territory.

The reactor is the brainchild of Bruno Coppi of the Massachusetts Institute of Technology who worked on MIT's Alcator tokamaks from the 1970s until the present day.

This is certainly a legitimate alternative to the budget-busting ITER that has been beset by delays and cost over-runs. Whether they can actually achieve the goal is another matter and the whole reason why this is being built in the first place.


Tuesday, April 27, 2010


WANDA at Berkeley Lab is ".. one of the world's first nanomaterials synthesis robots... "

Too bad WANDA doesn't look as attractive as EVE from "Wall-E".

Er... I need to get out more often....


Wichita State University Physics Dept. On The Chopping Block

Here comes another physics program that is slated to be "reoriented". The physics department, and degree program, at the Wichita State University in Kansas is being considered to be eliminated. I suppose if this is a school that emphasized mainly liberal arts subject areas, it is understandable. But WSU kinda sold itself as a school with a strong engineering program. So it is a bit confusing how they could hope to continue selling itself as that but lacks a physics department.

One also wonders if the data being used to argue for its elimination is outdated, as stated in the article.

But supporters of the physics department say demoting physics from a major to a grouping of courses would damage WSU's national reputation. The department chairman, professor Nick Solomey, said Miller's numbers are way out of date in that February study, and that Miller's proposal is destructive.

All the problems Miller cites did exist two years ago, Solomey said, when he was hired by the administration to revive the department. But he did revive it, he said; there are now 38 majors, and eight students graduating; there will be larger numbers in the year to come. The problem is well on it's way to being solved; the numbers trend is up, test scores are up, he said.

Other physics programs have had to face similar fate, with varying degree of success. We'll have to see how this turns out.


Monday, April 26, 2010

April 2010 Issue of Physics and Society Newsletter

The April 2010 issue of Physics and Society Newsletter is now available online.

In particular, one of the issues that could be a major problem some time soon and have not received the publicity that it deserves, is the issue on the isotopes production, especially the medical isotopes that will experience a severe shortage. This is discussed in a brief article in the newsletter, so it will give you a quick intro and update on the problem if you're not aware of it already. I've mentioned this potential problem in relation to particle accelerators.


Sunday, April 25, 2010

Hubble Telescope Turns 20

Happy 20th Birthday, Hubble Telescope.

This is one of the workhorses of astronomy/astrophysics. This "thing" has advanced so much of our knowledge of other parts of our visible universe.


Friday, April 23, 2010

Making Einstein's Idea Real

This is a very fascinating and informative Q&A with Charles Townes as part of the celebration of the 50th Anniversary of the laser. There's a lot of historical background information here on his effort in the invention of the maser, and later on, laser.

Several people at Columbia in the early 1950s, including physics Nobel laureate I.I. Rabi, told you that trying to build a maser was a waste of time. What made you disregard that advice?

I’m accustomed to being myself, being independent, and that’s a very important part of creativity. My parents taught me that, too. Don’t do what other people are doing; you do what you think is really right. I had to think about what these people were saying, yes, but it wasn’t troublesome or upsetting when someone disagreed with me. Luckily, I had tenure at Columbia. If I didn’t have tenure, that would have been a bigger problem certainly, whether I would have taken a chance or not [to build the maser], I’m not sure. After we built the maser, Rabi didn’t exactly apologize, but he did congratulate me on my work.

See? Even Nobel Laureates can be wrong! :)


Tales from the Quantum Frontier

This is an unusually good article on quantum physics aimed at the general public. It is unusually good because (i) it doesn't go overboard with all the weirdness of QM, and (ii) it actually provides links to actual physics papers as references! How many times have you seen article aimed at the general public, and published in the mass media do the latter?

No wonder Alan Boyle, the author of that article, has received all kinds of recognition.


Teaching Science to Nonscience Majors

A very nice article in Science Career section about various instructors teaching science topics to non-science major. A quote from a physics instructors reinforced what I've said earlier regarding communicating physics to the general public.

Teaching nonmajors has much in common with the work of science communicators. You have to learn something about a range of disciplines and social issues and stay current on "what's on the news," Moctezuma says. "I love science, but I'm also interested in other fields, and this allows me to explore some things beyond science and also how science influences and affects many different fields of study," he adds. Also important is not to fall into the trap of thinking it's easier than teaching majors. "There are probably some people who think ... if you can teach classical mechanics to physics students, you should be able to teach motion at a lower level," Schwarz says. "It's actually harder."

It definitely is. This is because, more often than not, what you think you are communicating or trying to convey is not what they understood. This makes it harder because you have to choose your words very carefully, and always have to realize the "pedestrian" meaning of the words and phrases that you chose. This pedestrian meaning is what the general public will attach these words and phrases to, not the physics definition. So this makes the job of communicating science (and physics) significantly harder.


Unconventional s-Wave Superconductivity in Fe(Se,Te)

This is an amazing experiment in more ways than one.

Abstract: The superconducting state is characterized by a pairing of electrons with a superconducting gap on the Fermi surface. In iron-based superconductors, an unconventional pairing state has been argued for theoretically. We used scanning tunneling microscopy on Fe(Se,Te) single crystals to image the quasi-particle scattering interference patterns in the superconducting state. By applying a magnetic field to break the time-reversal symmetry, the relative sign of the superconducting gap can be determined from the magnetic-field dependence of quasi-particle scattering amplitudes. Our results indicate that the sign is reversed between the hole and the electron Fermi-surface pockets (s±-wave), favoring the unconventional pairing mechanism associated with spin fluctuations.

T. Hanaguri et al., Science v.328, p.474 (2010).

What is amazing is that they not only managed to determine the pairing symmetry for this family of superconductors, but also were able, using STM no less, to detect the s±-wave pairing symmetry, which is not easy! See J.E. Hoffman article reviewing this work in the same issue of Science to understand why.

Is this the first ever experiment to actually make an observation of this pairing symmetry? I'm sure that it is the first ever using an STM.


Thursday, April 22, 2010

LCLS Achieved Completion Milestone

Congratulations to all the folks at SLAC's LCLS for completion of CD4 Milestone just today! Here's the official announcement.

Today at approximately 1PM, LCLS achieved its project completion (CD-4) milestone of delivering first photons to the Far Experimental Hall. This is a tremendous day for SLAC! I congratulate all of you who have worked so hard to make this happen. Above all, I want to congratulate and thank John Galayda for delivering this wonderful machine on time, on budget and with outstanding performance!


Well done, folks! This was one tough beast to construct, especially with such tight tolerances. It is an amazing accomplishment.


Wednesday, April 21, 2010

Physics and the 6-Day of Creation

It is a very clear example on what I mean by a good intention with a not-so-good outcome. The intention to educate the public in physics may be good, but often it leads to an unwanted bastardization of the physics itself. Deepak Chopra is one very good example. This is another.

This appears to be a Letter to the Editor by someone who learned about Relativity rather superficially.. "... especially in the Discover magazine with Einstein on the front cover... " no less. The writer seemed to be referring to one of the consequences of SR, which is time dilation. This "knowledge" was used to somehow justify the biblical description of the creation of the universe in 6 days.

And one thing struck with the theory that was shown in an illustration of a boy standing in the center of a circle with an old man riding around him at the speed of light. The theory shows that within a few minutes the young boy in the circle would be older than the man riding around him on the bike.

After we talked about that for a while, everything got plugged in. Time is different with speed and gravity and all those crazy variables. If this type of theory scientifically would exist, it blows the mind with the possibilites of everything else. If the universe is expanding, then if we rewind far enough back, the time dilation would be different. If that boy in the middle is older than that man on the bike, then he still went through the aging process, much like Earth going through the billions of years of aging.

Maybe a day really was nearly a billion years and maybe not much was lost in translation.

It is one thing to actually think and wonder about such a thing, especially considering that one only has a superficial understanding of the physics, it is another to have no qualms to actually write to a paper and let it be known to the world about it. There doesn't seem to be any kind of "quality control" on the part of many, especially in double-checking to see if one has fully understood what one is about to use and present to the "world".

The flaw in this argument, of course, is the very common mistake that almost everyone makes when they first encounter SR. Time dilation is the apparent slowdown of time in ANOTHER REFERENCE FRAME AS VIEWED BY SOMEONE IN A DIFFERENT REFERENCE FRAME. If A views the clock of B, where B is moving relative to A, then A sees B's clock as being slow. A doesn't see HIS clock as being any slower or different. And the same could be said from B's point of view. B sees clocks in A reference frame as being slower than his. B doesn't see his clock being any different.

Now, unless the author is implying that the universe literally has a motion that is VERY fast when compared to "God", so much so that god sees the clock in the universe as being time dilated, then the whole argument above makes no sense. Furthermore, why would god describes the formation of the universe from that point of view? After all, everything else about the genesis was described from the point of view within the universe itself, so the proper time to be used here is the local time of the universe. This, of course, is ignoring the lack of definition for "6 days", considering that Earth didn't come into existence until the final days.

While we can't stop some poor misguided souls from taking something and completely bastardizing it, as science writers and communicators to the public, we should always, in the back of our minds, think of what we say and how the public might understand what we say, because when they do this to physics, it isn't progress, but rather a step backwards. They understood the WRONG THING. I've often wondered in cases like this whether no knowledge is better than having the wrong knowledge. Having the wrong knowledge can often be dangerous.


Tuesday, April 20, 2010

Yoctonewtons Of Force Measured

The smallest ever measurement of a force has reported {link open only for a limited time}.

The result, measuring mere yoctonewtons (10–24 newtons), beats previous record lows by several orders of magnitude. The group behind the measurements, based at the National Institute of Standards and Technology in Boulder, Colorado, hopes that the technique can eventually lead to new tools for measuring the minuscule features of materials' surfaces.

The preprint cited can be found here.


Monday, April 19, 2010

A New Limit on the Light Speed Isotropy

All those theories that have the possible Lorentz violation will have to deal with a new lower and more stringent limit on light speed isotropy. A new study base on the Compton edge measurement at the ESRF has imposed a new limit on such isotropy.

Abstract: When the electrons stored in the ring of the European Synchrotron Radiation Facility (ESRF, Grenoble) scatter on a laser beam (Compton scattering in flight) the lower energy of the scattered electron spectra, the Compton Edge (CE), is given by the two body photon-electron relativistic kinematics and depends on the velocity of light. A precision measurement of the position of this CE as a function of the daily variations of the direction of the electron beam in an absolute reference frame provides a one-way test of Relativistic Kinematics and the isotropy of the velocity of light. The results of GRAAL-ESRF measurements improve the previously existing one-way limits, thus showing the efficiency of this method and the interest of further studies in this direction.

The new limit is Delta(c)/c of less than 1 e-14.


The Day Einstein Died

For 55 years, many of these Ralph Morse pictures never made it into print at the request of Albert Einstein's son. Only now is Life Magazine printing out the pictures of Einstein's office other related scenes. All of them were taken on the day that Einstein died. A bottle of scotch got him access to Einstein's office.

"I grabbed my cameras and drove the ninety miles to Princeton," Morse recalls. "Einstein died at the Princeton Hospital, so I headed there first. But it was chaos -- so many journalists, photographers, onlookers milling around outside what, back then, was a really small hospital. 'Forget this,' I said, and headed over to the building where Einstein's office was. On the way there, I stopped and bought a case of scotch. I knew people might be reluctant to talk to me, and I knew that most people were happy to accept a bottle of scotch instead of money if you offered it in exchange for their help. So, I get to the building and nobody's there. I find the superintendent, give him a fifth of scotch, and he opens up Einstein's office so I can take some photos."


Sunday, April 18, 2010

Soudan Lab Open House

Oh, I would go if I could!

The Soudan underground lab will be having its Open House on May 8, 2010.

The public is welcome to travel a half-mile underground and visit the Soudan Underground Physics Lab at an open house set for May 8.

Participants will discover the data collected during the years that the MINOS detector has been operating. The Fermi National Accelerator Lab has been sending a beam of neutrinos to the Soudan Lab since the first one was detected March 20, 2005. It will also be an opportunity to ask the experts about the new project, NOvA, a 15 kiloton detector under construction on the Ash River Trail to study other characteristics of the neutrino. The third major experiment is the Cryogenic Dark Matter Search.

When was the last time you get to visit a half-mile-underground physics lab? That in itself is a good-enough incentive.


Saturday, April 17, 2010

Can We Be Moral Without Science?

The answer is no, at least, from this essay that argues that a society needs science to maintain moral values.

Can science help us be moral? Yes, science frees our intellect from inadequate morals which have impeded humanity and provides knowledge from which we make better moral decisions. We should not perceive science and religion as opposing principles, but as complementary choices - compatible pathways to progress. Perhaps a more important question is, can we be moral without science? In today's scientific era, I think not.

I haven't decided if I quite agree with the whole essay. I've never thought of science in this light before, so this is something new.


Friday, April 16, 2010


The abbreviation alone is enough to confuse anyone.

This is a valiant attempt at answering some of the general questions regarding the LHC. Still, there are quite a few errors or inaccuracies. The two glaring ones are:

Q. What does the name Large Hadron Collider mean?

A. The LHC is "large'' because it's the biggest assemblage of scientific tools ever gathered in one place. It works with "hadrons'' — physicist jargon for protons and neutrons that make up the nucleus of an atom. It's a "collider'' because it smashes protons — tiny subatomic particles — together so that scientists can peer at their shattered innards.

Hadrons are not a physicist jargon for protons and neutrons. It is essentially anything made up of quarks, which means they could be baryons and mesons.

Q. Will the LHC help explain how quarks combined to create matter?

A. That's one of the major goals of the project. Scientists hope they will find in the debris of the collisions evidence of an as yet undiscovered subatomic particle called the "Higgs boson,'' named after a Scottish physicist who predicted such a particle in 1964. Like the gluon, bosons are particles that have no mass but carry a force. Scientists think the Higgs boson, if it exists, is the particle that allows energy to turn into mass. The theory is that Higgs bosons are spread throughout the universe, like flowers in a field. Particles acquire mass — in other words become matter — by interacting with the Higgs field. That's why physicist Leon Lederman called the Higgs the "God Particle'' in a 1993 book of that name.

Bosons are particles with integer quantum spin. That's it. It happens that all our "force-carrying particles" are also boson, but all bosons are not "force-carrying particles".

While these errors are not as horrible as the one we've seen previously, one again is left to wonder why they don't have a qualified physicist go over these things before they publish it. These errors are not something that is so highly specialized or so subtle. They are often something even an undergrad can spot from 10 miles away.


Watch Out For A Nobel Prize At Your Local Pawn Shop

This is utterly bizarre!

A man broke into Nobel Laureate Roy Glauber's home and not only slept in his bed, but also possibly took his Nobel Prize medal!

Stephen Beaulieu, 42, of Skowhegan, Maine - a disheveled drifter with champagne tastes - broke into Harvard University Professor of Physics Roy J. Glauber’s home overlooking Spy Pond in Arlington last month, slept in one of his beds, stubbed out a cigarette on a nightstand and stuffed his face with imitation lobster and smoked oysters bought with his food stamp card, investigators said.

Police, meanwhile, are trying to track down Glauber’s Nobel Prize for his work on the behavior of light, as well as a Nobel replica and a Spanish Academy of Sciences Gold Medal he has been unable to locate since the break-in.

“Obviously, they mean a great deal to me,” the 84-year-old brainiac said. “I cannot imagine what good they would be to anybody.”

I definitely hope they recover the medal.


Thursday, April 15, 2010

Random Numbers Certified by Bell’s Theorem

Haven't had time to closely read this yet, but it is a good one.

Abstract: Randomness is a fundamental feature of nature and a valuable resource for applications ranging from cryptography and gambling to numerical simulation of physical and biological systems. Random numbers, however, are difficult to characterize mathematically, and their generation must rely on an unpredictable physical process. Inaccuracies in the theoretical modelling of such processes or failures of the devices, possibly due to adversarial attacks, limit the reliability of random number generators in ways that are difficult to control and detect. Here, inspired by earlier work on non-locality-based and device-independent quantum information processing, we show that the non-local correlations of entangled quantum particles can be used to certify the presence of genuine randomness. It is thereby possible to design a cryptographically secure random number generator that does not require any assumption about the internal working of the device. Such a strong form of randomness generation is impossible classically and possible in quantum systems only if certified by a Bell inequality violation15. We carry out a proof-of-concept demonstration of this proposal in a system of two entangled atoms separated by approximately one metre. The observed Bell inequality violation, featuring near perfect detection efficiency, guarantees that 42 new random numbers are generated with 99 per cent confidence. Our results lay the groundwork for future device-independent quantum information experiments and for addressing fundamental issues raised by the intrinsic randomness of quantum theory.

S. Pironio et al., Nature v.464, p.1021 (2010).

A news report on this paper can be found here.


Wednesday, April 14, 2010

Photon Detector With 99% Efficiency?


NIST scientists are reporting a new detection scheme that reportedly can get up to 99% efficiency.

Using essentially the same technology that permitted them to achieve 88 percent detection efficiency five years ago,** the team has enhanced its ability to detect photons largely by improving the alignment of the detector and the optical fibers that guide photons into it. The basic principle of the detector is to use a superconductor as an ultra-sensitive thermometer. Each individual photon hitting the detector raises the temperature—and increases electrical resistance—by a minute amount, which the instrument registers as the presence of a photon.

According to team member Sae Woo Nam, the advantage of this type of single photon detector is that the new detector design not only measures lower levels of light than have ever been possible, but does so with great accuracy.

I wonder if such a detector can be employed in the Bell-type experiments. This type of efficiency can greatly reduce the background subtraction and also lay to rest the detection loophole argument.


A Hands-On Introduction to Single Photons and Quantum Mechanics for Undergraduates

This is another very useful demonstration for undergraduate students on the quantum effect of light, and how it differs from the classical description. Fascinatingly enough, it appears that this is a lab at the sophomore level. Maybe sophomores nowadays are more "sophisticated" than when I was in college, but this certainly would require quite a bit more knowledge of QM than I would have had back then at this level.

Abstract: We describe a series of experiments used in a sophomore-level quantum physics course that are designed to provide students with a hands-on introduction to quantum mechanics. By measuring correlations, we demonstrate that a helium-neon laser produces results consistent with a classical model of light. We then demonstrate that a light source derived from a spontaneous parametric down-conversion process produces results that can only be described using a quantum theory of light, thus providing a (nearly) single-photon source. These single photons are then sent into a Mach–Zehnder interferometer, and interference fringes are observed whenever the path of the photons cannot be determined. These experiments are investigated theoretically using straightforward quantum-mechanical calculations.

B.J. Pearson and D.P. Jackson, Am. J. Phys. v.78, p.471 (2010).

What makes this paper so wonderful is that it is full of various references and resources, and also discussed many of the physics background information. So for someone who wants to learn about the physics of the phenomena, this is almost a one-stop shop.

This paper compliments the ones that I've mentioned earlier that were also undergraduate laboratory or demonstration.


Tuesday, April 13, 2010

Reusing Plastic Bags

Those ever-present and annoying plastic bags may find a valuable second life after all.

Converting them into carbon nanotubes might just be worth its weight in gold.

I no longer use them when I go grocery-shopping. In fact, if I remember them, I tend to bring reusable bags whenever I go shopping, even in shopping malls. These bags are a menace when they blog drainage system.


Single Photon Quantum Erasing: A Demonstration Experiment

OK, I had every intention to read this paper first and then do a report on it afterwards. But y'know, work and life got in the way, and the paper is still on my desk and remained unread. So I'm going to just highlight it here and point to the link at the IoP website now so that it is within the 30-day online print window, and you can get the paper yourself for free (upon registration).

Abstract: In the conventional interpretation of quantum mechanics the interference of particles in a two-beam interferometer is closely related to the problem of which-way information. One of the mysteries of quantum mechanics relies on the assumption that the wavefunction of each photon propagates simultaneously along both classically allowed paths, and that interference arises as a consequence of the indistinguishability of those paths. Any attempt to obtain which-way information by putting individual labels on the photons in each pathway inevitably destroys interference. However, even in cases in which the photons carry which-way labels, it is possible to erase those labels after the particle has left the interferometer. The erasing process (partly or completely) destroys the which-way information, and thereby restores interference. This phenomenon is known as quantum erasing. Here we present a lecture demonstration experiment of quantum erasing based on a Mach–Zehnder interferometer operated with single photons.

T.L. Dimitrova and A. Weis, Eur. J. Phys. v.31, p.625 (2010).

These authors have published another paper that I liked and highlighted before on the so-called wave-particle duality. I'm guessing this is as good as the previous one, but like I said, I haven't read it yet. But that shouldn't stop you from looking over it! :)


Monday, April 12, 2010

The Garden of Cosmic Speculation

Er.. I don't get it.

The garden, at Jencks' private home at Portrack House in Dumfries and Galloway, Scotland, is designed to represent themes and ideas rather than what many see as the real purpose – to mount a horticultural display.
Yesterday, Jencks played host to physicist Professor Peter Higgs and director-general of CERN, Professor Rolf-Dieter Heuer, to discuss the possibility of creating a similar concept in Geneva.

Wow. You would think the Director of CERN has more things on his plate to worry about with the LHC than thining about what type of a garden to put at CERN. Can't he just leave this to people in charge of the grounds?


Friday, April 09, 2010

Measurement of an "Exotic" Nucleus

A significant improvement in energy resolution of a nucleus energy state has been reported using HELIOS.

Nuclear physicists at the Argonne National Laboratory in the US have obtained the first results from a new spectrometer that contains the magnet from a mothballed MRI machine. They used the Helical Orbit Spectrometer (HELIOS) to make the most precise measurements to date of two excited states of boron-13 – an "exotic" nucleus containing an unusually high ratio of neutrons to protons. The researchers say that HELIOS could eventually yield precise data on the structure of a range of rare nuclei.

Carried out at Argonne's ATLAS facility, the experiment involves slamming a beam of stable boron-11 nuclei, containing five protons and six neutrons, into a gas cell filled with much lighter deuterium nuclei, which have just one proton and neutron. This method of rare-isotope production – known in the trade as "inverse kinematics" – leads to neutrons being "stripped" from the deuterium and tacked onto the nuclei in the beam. The result is a "secondary" beam of short-lived boron-12 nuclei containing seven neutrons.

It's a rather amusing, and some time confusing, situation there at Argonne. You got a nuclear physics accelerator/collider facility named ATLAS in the Physics Division. But there's also members of the ATLAS collaboration in the High Energy Physics Division working on the ATLAS detector at the LHC! I'm sure the Physics Division would argue that their ATLAS were there long before the LHC was even a glimmer in someone's eyes. Still, it made for many confused look, especially for visitors and people not familiar with nuclear/high energy physics.


Thursday, April 08, 2010

Life Of A LHC Operator

Symmetry Breaking has a close look at the people responsible for making sure the proton beams are running and colliding at the LHC - the LHC operators.

LHC operators are responsible for running the world’s largest particle accelerator, ensuring that all of the equipment on the seventeen-mile ring works in synchrony. The operators include machine coordinators, engineers in charge, and teams of experts who specialize in different accelerator subsystems.

Twice a day, the machine coordinator leads an informational meeting to update operators on the status of the LHC and outline the tasks at hand for operators on shift. Depending on the mode of operation, whether preparing for particle beams or colliding particles, the tasks will vary.

While these are the people you see during the commissioning process of the LHC, they tend to become the unsung heroes of the whole operation. This is because all the "physics" of the LHC reside in the several detectors that have their own group of people and collaborators. In fact, these detectors such as ATLAS, CMS, etc. have their own control rooms with their own "operators". If you hear major particle physics discoveries, they will come from these detectors. What the LHC operators, engineers, and physicists do are more of interest to those involved in studying accelerator and beam physics, which isn't one of the usually "sexy" areas of physics that get the front-page coverage. So it is nice that these people are given some recognition here.


Free Public Lecture

There will be a free public lecture at the U. of Iowa in Iowa City on April 27 as part of the LaserFest activity commemorating 50 years of the invention of the laser.

"Controlling the Quantum World with Lasers" is the title of a talk to be given by Michael Flatte, professor in the University of Iowa Department of Physics and Astronomy, from 7 to 8 p.m. Tuesday, April 27, in Lecture Room 1 of Van Allen Hall, Dubuque and Jefferson streets, on the UI campus in Iowa City.

Hosted by the UI College of Liberal Arts and Sciences Department of Physics and Astronomy faculty, staff, and students, the event is free and open to the public.

The lecture is the first in a series of UI talks recognizing LaserFest and "2010 -- Year of the Laser," an international celebration of 50 years of laser innovation. Information on LaserFest can be found at:


Tuesday, April 06, 2010

Taking The Mind Of God Out Of Science

A very thought-provoking essay by Marcelo Gleiser, which I think, is primarily aimed at theoretical physicists and their models of our world. In fact, I think it is a very sharp criticism of string theorists.

The one aspect that isn't clearly mentioned in the essay is the role of empirical verification. While there is a mentioned of the CP violation that "... crushed the symmetries that we have hoped for... ", this really is a direct outcome of an unexpected experimental discovery, not out of some theoretical predictions. This lack of empirical observation is the reason why String Theory is a myriad of many (infinite?) different theories and models that no one can select. It lacks any experiment that can falsify one over the other.

So maybe the problem isn't the holding on to the old "truth and beauty", but rather holding on to something that, for so long, can't be verified.


Monday, April 05, 2010

Bad Glossary of Particle Physics Terms

Good intentions, bad execution.

Reuters decided to published what it calls a "Factbox", containing a list of glossary of terms commonly used in particle physics reporting. Unfortunately, it is wrought with errors and misleading definitions. Here it is in its full glory (I'm copying the entire list in case the news item gets deleted.

CERN - The European Organisation for Nuclear Research, a major laboratory located near Geneva on the Swiss-French border.

PARTICLE - An object which is sub-atomic -- smaller than an atom -- and has a definite mass and charge.

HADRON - A particle with mass, made up of smaller units called quarks that are bound together. Protons and electrons are types of hadron.

LHC - CERN's Large Hadron Collider that has been under development for 20 years, with a total project cost of 10 billion Swiss francs ($9.4 billion).

PARTICLE ACCELERATOR - A machine used to accelerate streams of particles in a defined direction at high speeds. The LHC is the world's largest.

COLLIDER - An accelerator in which two beams traveling in opposite directions are steered together to induce high-energy collisions between particles in one beam and those in the other.

HIGGS BOSON - A theoretical particle which is thought to give matter its mass. First proposed by Peter Higgs of the University of Edinburgh in 1964. The LHC should confirm whether it exists.

STANDARD PRINCIPLE - The standard theory of modern physics, based on two other theories -- general relativity and quantum mechanics. Its main weakness is that it cannot yet fully describe gravity or mass.

You get no points for pointing out the error in the "example" of a hadron, or the weird definition of a "particle" (is a neutrino not a particle then since it doesn't have a charge? Really?), and the rather strange definition of the Standard "Principle" (Standard Model, and when did GR got into it?).

The sad thing in all of this is not that they got it wrong. I would not expect a reporter to get all of this correct. The sad part is that (i) no one bothers to fact-check them and (ii) they don't have a expert staff or a physicist on call to give this a quick glance. How difficult can it be? It just shows a total lack of respect for this area of reporting.


The Physics of Cooking Oils

More culinary-related item for you to digest {pun intended}. This time, we look at the physics and chemistry of cooking oil, including all that you wanted to know about the physics and chemistry of olive oil.

The nice thing about this article that is utterly lacking in many news articles is that they included references! I love that! We can at least double check, or read in greater detail, some of these things and look at the sources.


Neal Lane Looks At The Future Of US Science

Neal Lane, former Science Advisor to President Bill Clinton, gets a Q&A on the future of US Science. One of the issues brought up is this:

Q.What can scientists do to make sure the public has a better understanding of science and its role in the modern world?

There is so much now known about the natural world and the engineered world that nobody can know much of it to any depth, including scientists. When people want to know something specific about science, they go to the Internet. I think scientists will need to give a lot more attention to the Internet - how blogs are used, who writes for them and how the public reads them.

So how DOES the public read this blog? :)


Friday, April 02, 2010

Thursday, April 01, 2010

General Relativity in the Undergraduate Physics Curriculum

This is not a new paper. It appeared in AJP in 2006. But for some reason or another, I came across it lately in one of my searches, and I don't think I've highlighted this before. This is an excellent presentation by James Hartle on the rationale to introduce General Relativity to undergraduate physics students. This is no easy task because GR does require a bit of sophistication, especially with mathematics. But beyond that, the paper is actually a good intro to GR where one can actually get a taste of basic GR concepts.

A good paper to read.