Wednesday, June 27, 2012

£1000 Reward For The Best Explanation Of The Mpemba Effect

This thing will just not go away! :)

The UK Royal Society of Chemistry is offering a £1000 cash prize for the best explanation for the Mpemba effect. This is where hot water appears to freeze faster than cold water.

It's a question that has perplexed scientists for centuries and now the Royal Society of Chemistry is offering £1000 to whoever can come up with the best explanation for what is referred to as the The Mpemba Effect.

Judges will be looking for an outside-the-box submission that is creative and eye-catching.

The deadline for submissions is July 30.
Creative and "eye-catching"? What about being CORRECT and verified?

Hum.. oh well. The link to the contest is here where it is described in a bit more detail:

Submissions can be based on, and reference, existing research. The winning submission will be scientifically sound, and arresting in presentation and delivery. The judges' decision will be final.
We shall see! If you want to catch up on all the stuff I had linked to on this effect, click here, here, and here.

Zz.

Monday, June 25, 2012

July 4th, 2012 - Birth Date For The Higgs?

I suppose everyone (or almost everyone) is aware of the press release out of CERN announcing a seminar on the Higgs on July 4th. But in case you are one of the few who didn't hear about it, here is the press release again:

Geneva, 22 June 2012. CERN will hold a scientific seminar at 9:00CEST on 4 July to deliver the latest update in the search for the Higgs boson. At this seminar, coming on the eve of this year’s major particle physics conference, ICHEP, in Melbourne, the ATLAS and CMS experiments will deliver the preliminary results of their 2012 data analysis.

“Data taking for ICHEP concluded on Monday 18 June after a very successful first period of LHC running in 2012,” said CERN’s Director for Accelerators and Technology, Steve Myers. “I’m very much looking forward to seeing what the data reveals.”

The 2012 LHC run schedule was designed to deliver the maximum possible quantity of data to the experiments before the ICHEP conference, and with more data delivered between April and June 2012 than in the whole 2011 run, the strategy has been a success. Furthermore, the experiments have been refining their analysis techniques to improve their efficiency in picking out Higgs-like events from the millions of collisions occurring every second. This means that their sensitivity to new phenomena has significantly increased for both years’ data sets.  The crunching of all this data has been done by the Worldwide LHC Computing Grid, which has exceeded its design specifications to handle the unprecedented volume of data and computing.  

“We now have more than double the data we had last year,” said CERN Director for Research and Computing, Sergio Bertolucci, “that should be enough to see whether the trends we were seeing in the 2011 data are still there, or whether they’ve gone away. It’s a very exciting time.”

If and when a new particle is discovered, ATLAS and CMS will need time to ascertain whether it is the long sought Higgs boson, the last missing ingredient of the Standard Model of particle physics, or whether it is a more exotic form of the boson that could open the door to new physics.

“It’s a bit like spotting a familiar face from afar,” said CERN Director General Rolf Heuer, “sometimes you need closer inspection to find out whether it’s really your best friend, or actually your best friend’s twin.”

The Standard Model gives an extraordinarily precise picture of the matter that makes up all the visible universe, and the forces that govern its behaviour, but there are good reasons to believe that this is not the end of the story. For example, we know from observation that the visible universe is just 4% of what seems to be out there.

Physicists from around the world gathering in Melbourne for the ICHEP conference will be able to join the seminar via a live two-way link. The seminar will be followed by a press conference at CERN. It will be available via webcast at http://webcast.cern.ch, accompanied by plain language interpretations from physicists accessible in blogs and chats from the webcast site.
I fully expect that they will announce the discovery of the Higgs. I would be hard for me to believe that they would do all this just to tell people that they didn't find anything.

Zz.

Friday, June 22, 2012

Hot Wheels Double Loop

Oh, here's something fun to give to your students to work on!

At the LA X-Games, Hot Wheels will attempt a "6-story" vertical loop!

On June 30, drivers in a Hot Wheels double loop at X Games Los Angeles 2012 will attempt to break a world record for racing two vehicles through a six-story double vertical loop. Two drivers will accelerate to 52 mph, enter a 66-foot tall loop and hit seven times normal gravity as they drive through the loop.
Of course, it would be nice to have an exact diameter of the loop beyond just "six-story" measurement. Still,  using an estimate of the car's mass and the height of the loop, calculate the minimum speed that the vehicle must have to successfully make the loop. One almost might want to consider if neglecting the rotational energy in the wheels is acceptable.



Should be fun to do such calculation and make a prediction before hand if this will be successful or not! :)

Zz.

Wednesday, June 20, 2012

Higgs Discovery Rumors

Ah, don't we love rumors like this that set many parts of the physics community on fire?

Unconfirmed rumors (is there any other kind?) are abound that the data analysis out of ATLAS and CMS are each producing 4-sigma signal at where the Higgs were expected. So far, indications point to an announcement of the Higgs discovery at the upcoming conference in Australia starting on July 4th.

The latest Higgs rumors suggest nearly-there 4-sigma signals are turning up at both of the two separate LHC experiments that are hunting for the particle. As physicist Philip Gibbs points out on his blog, Vixra log, if each experiment is seeing a 4-sigma signal, then this is almost definitely the long-sought particle. Combining the two 4-sigma results should be enough to clear that 5-sigma hurdle.
I asked a couple of the ATLAS people here at the lab, and while they didn't tell me anything specific, they certainly gave away the impression that whatever they are getting is quite "compelling", which doesn't say much. But these are the people who tend to not overhype things. So my gut instinct here is that we are going to hear something soon enough.

Zz.

Tuesday, June 19, 2012

Job Advertisements For Theorists and Experimentalists In Physics Today Apr-Jun 2012

This is a follow-up to the previous post I did in counting the different number of job advertisements in Physics Today. This time, I've included the job advertisement that appeared in the June 2012 issue.

So here is the job distribution:

1. Number of jobs looking only for experimentalist = 25
2. Number of jobs looking only for theorist = 7
3. Number of jobs looking for either or both = 21

Again, I've tried to not double-count, i.e. if I recall seeing the same advertisement for the same position in an earlier issue, I do not include that a second (or third) time. So I'm trying to count the number of unique jobs being advertized.

Additional note: a lot of jobs that are included in #3 (i.e. seeking for either experimentalists or theorists) are often temporary teaching jobs. I decided to include them in the count even though one may not consider this as the start of a career.

Zz.

Saturday, June 16, 2012

Son Of A Physicist!

Oh no, I wasn't cussing! :)

Throughout history, there have been many situations where the off-springs followed in the footsteps of their parents. The world of physics isn't an exception. There have been many notable parent-offspring physicists - the Bohrs, the Braggs, the Thomsons, etc.

Strangely enough, in my circle of physicist friends at work, I know of no one whose offspring is following in his/her footsteps. Zilch! None of the kids want to go into physics. Granted, majoring in physics is not one of the more popular line of study in college, so the odds are already stacked against it. But I would think that if there's demographic that would be more amenable to wanting to do physics, it would be from this group of people, since at least one of their parents is a physicist.

So I wonder why don't I see more of their kids going into physics? Is it because the parents are trying to get the kids to carve out their own destiny? Is it because the kids have seen the nature of the work and decided that this isn't something they want to do? Or is it due to something else?

What about you? Are you a physicist with a child/children? Any of your kids are inclined to go into physics?

Zz.

Friday, June 15, 2012

FBI Files On Feynman Released

The FBI Files on Richard Feynman has been released, not that it makes any difference.

The FBI began keeping an eye on Feynman after other members of the Manhattan Project, which built the first atomic bomb, turned out to be Soviet spies, including Klaus Fuchs, the project's primary physicist. The documents, 361 pages, record statement after statement from the physicist's friends and colleagues, mostly praising Feynman for his brilliance, trustworthiness and loyalty to the country.


The documents available at MuckRock detail, for example, how in 1958 Feynman, then at Caltech, received an invitation from the Soviet Union to attend a physics conference in Moscow. After discovering this invitation by sifting through the Soviet ambassador's trash, the FBI began looking into his plans.
And for anyone who thinks he was a nice guy and fun to be around with, this might change your mind:

In a note to the director of the FBI, dated July 29, 1958, Special Agent-in-Charge (SAC) Los Angeles notes details from an L.A. Times article from two years prior, regarding his relations with his wife: "The appointee's wife was granted a divorce from him because of appointee's constantly working calculus problems in his head as soon as awake, while driving car, sitting in living room and so forth, and that his one hobby was playing his African drums. His ex-wife reportedly testified that on several occasions when she unwittingly disturbed either his calculus or his drums he flew into a violent rage, during which time he choked her, threw pieces of bric-a-brac about and smashed the furniture."
I suppose this makes for a good bedtime stories. It is also one aspect of his life that is missing in the many biographies written about him.

Zz.

Thursday, June 14, 2012

Job Advertisements For Theorists and Experimentalists In Physics Today Apr/May 2012

Anyone reading my blog on the Problem in Pursuing To Be A Theorist would have read comments that disputed my claim that there are less job positions for theorists to practice what they want to do versus that of experimentalists. To make a check on how far off (or on) I was, I did a quick count on the job advertisements on the pages of Physics Today April and May 2012 issues. I look at each advertisement, categorize the job description into three categories:

1. Job looking only for experimentalists
2. Job looking only for theorists
3. Job that either has no clear description, or a job that either a theorist or experimentalist can do. This is often a position higher up in administration, i.e. director of a projects or lab, not something that a new PhD or Postdoc would qualify for.

What I discovered was this distribution:

1. Number of jobs looking only for experimentalist = 19
2. Number of jobs looking only for theorist = 5
3. Number of jobs looking for either or both = 14

I discounted job advertisements in the May issue that were identical to the ones found in the April issue.

From looking at this quick count, we see that the ratio of experimentalist-only jobs to theorist-only jobs is almost 4:1. I will not be surprised that this is a common ratio if I were look at other issues. Maybe I'll check the job listing on the AIP webpage and see what this turns out to be.

Zz.

Wednesday, June 13, 2012

Fusion Energy Research Funding Might Be Restored

Due to the effort of the lone physicist in the US Congress, the US House of Representatives passed a bill to restore funding for fusion energy research, which includes funding for the Princeton Plasma Physics Lab.

The funding, which supports the Princeton Plasma Physics Lab and other energy research laboratories, was not included in the President Obama’s fiscal year 2013 budget request. Without the funding, the lab would face major cutbacks on research projects and staff reductions of up to 100 people, including scientists, engineers, and lab technicians.
While I know that Holt has a tie with PPPL, I wonder if he can muster the same support for high energy physics funding, which looks extremely bleak.

Zz.

Tuesday, June 12, 2012

Anticipation For The Higgs Builds Up

Boy, this is almost as exciting as anticipating the next Apple iPad or iPhone! Speculation runs rampant!

It appears that the cut-off date for the first set of data analysis at the LHC has come and gone. So now there are "leaks" here and there indicating that there's a good chance of an announcement soon from the LHC on the issue of the Higgs.


Poring over huge volumes of data, CERN physicists are confident they are now closer to achieving that aim, outside scientists with links to two key research teams at the Switzerland-based facility said.

"They are getting quite fired up," one scientist outside CERN but with links to the experiment who declined to be named told Reuters.

Strong signs of the Higgs were being seen in the same energy range where it was tentatively spotted last year, the scientists added, even though the particle is so short-lived that it can only be detected by the traces it leaves.
.
.
The scientists spoke of their CERN colleagues' progress after research chiefs at the Swiss facility decreed a cut-off last weekend in the processing of all data related to the search for the particle ahead of a major physics conference, ICHEP, in Melbourne in mid-July.
We shall see. Don't count your bosons before they are detected!

Zz.

Monday, June 11, 2012

Winner of "What Is A Flame" Challenge

OK, I didn't even know that there was such a challenge. Apparently, they got quite a number of submission too! And they got a winner!

Ames, who is studying for his Ph.D. in quantum optics at the University of Innsbruck, Austria, got national recognition this month when his 71/2-minute video was selected as the best explanation of flame to a young audience. The worldwide contest, run by Stony Brook University in New York, was inspired by actor and visiting professor Alan Alda and was judged by 6,000 sixth-graders.

The award was given by the Stony Brook Center for Communicating Science, a part of its School of Journalism.

Ames’ video bested 800 entries by getting the top number of rating points from sixth-graders in 131 schools.
So I went scrambling off to YouTube to see if I can find the video, and I did!




Zz.

Saturday, June 09, 2012

Laser Beam May Replace X-ray?

The quality of science reporting in the news has taken a new low. Just when you think it can't get any worse, it did!

This "news" report from CNN, no less, has way too many things wrong with it, I don't even know where to start. For posterity, I'm going to copy it wholesale, and I'd love to have someone from CNN tells me to take it down so that I can tell them what a stupid job of reporting they have done.

Laser beam may one day replace X-rays

Researchers at the University of Colorado have made a breakthrough that may one day help doctors detect disease earlier and with more accuracy.

Based on the hypothosesis of Dr. Tenio Popmintchev, researchers have created a laser beam by adding 5,000 photons together. Previously, two photons were typically used to create laser beams. This is the first time so many photons have been successfully added together.

The result is a more efficient and easier to set up X-ray, according to Dr. Margaret Murnane.

"If we can push this further, and we don’t know how far into the X-ray region we can push this technology, there's a chance we can change your doctor or dentist's X-ray device to a laser version." Murnane said.

"The image would be much crisper. It could really get high resolution X-rays so you could detect disease much earlier."

But that is still a while away - possibly around 10 or 20 years guessed Murnane.

In the meantime, the breakthrough sheds light on how heat flows in very small devices, which may allow scientists develop more energy efficient data storage devices, better understanding of solar energy harvesting and better nano electronics, "so your laptop doesn't heat up so fast," Murnane said.
I mean, where do you even begin? The title itself is glaringly wrong! "Laser beam" can be any EM radiation. This means that even x-ray can be a laser. That's what has been done at SLAC's LCLS, where they have generated x-ray lasers using FELs! Oy freaking vey!

Read the comments accompanying this article. They are unanimously condemning the horrible quality of this article.

CNN should be ashamed of  themselves for putting out such garbage in plain sight.

Zz.

Edit: If you want to more a more accurate report of this work, check out this link.

Friday, June 08, 2012

Confirmed: OPERA Superluminal Neutrino Result Was False!

At the 25th Neutrino conference in Kyoto, it was announced that the latest result of the neutrino speed measurement from CERN to Gran Sasso is consistent with the speed of light.

At the 25th International Conference on Neutrino Physics and Astrophysics in Kyoto today, CERN Research Director Sergio Bertolucci presented results on the time of flight of neutrinos from CERN to the INFN Gran Sasso Laboratory on behalf of four experiments situated at Gran Sasso. The four, Borexino, ICARUS, LVD and OPERA all measure a neutrino time of flight consistent with the speed of light. This is at odds with a measurement that the OPERA collaboration put up for scrutiny last September, indicating that the original OPERA measurement can be attributed to a faulty element of the experiment’s fibre optic timing system.
Case closed.

Now, I'd like to hear from all those theorists who posted all those silly papers on ArXiv formulating the concept of superluminal neutrinos. What do you have to say for yourself?

Zz.

Edit: this article from Science has more details and more links.

Thursday, June 07, 2012

Light Shows Non-Classical Properties, But I Don't Get It

OK, this is where you can help me understand this paper in the context of the press report.

This is the paper:

E. Kot et al., "Breakdown of the Classical Description of a Local System", Phys. Rev. Lett., v.08, p.233601 (2012).

Abstract: We provide a straightforward demonstration of a fundamental difference between classical and quantum mechanics for a single local system: namely, the absence of a joint probability distribution of the position x and momentum p. Elaborating on a recently reported criterion by Bednorz and Belzig [ Phys. Rev. A 83 052113 (2011)] we derive a simple criterion that must be fulfilled for any joint probability distribution in classical physics. We demonstrate the violation of this criterion using the homodyne measurement of a single photon state, thus proving a straightforward signature of the breakdown of a classical description of the underlying state. Most importantly, the criterion used does not rely on quantum mechanics and can thus be used to demonstrate nonclassicality of systems not immediately apparent to exhibit quantum behavior. The criterion is directly applicable to any system described by the continuous canonical variables x and p, such as a mechanical or an electrical oscillator and a collective spin of a large ensemble.

From a quick reading of the paper, they are trying to show this:

Classically, the phase space distribution Wðxi; piÞ is the joint probability of finding the system in an infinitesimal area around x = x_i, p = p_i, and hence it obeys all the requirements of a probability distribution including being a non-negative function. As mentioned, in the case of a quantum phase space formulation, introduced by Wigner [9], the Heisenberg uncertainty renders this definition meaningless, as a joint probability distribution for x and p does not exist. The phase space distribution is only defined through the single coordinate (marginal) distributions, projected from the distribution function [10] and this relaxation of constraints allows for negative values of the function in areas smaller than hbar. This negativity is not directly observable due to the vacuum fluctuations preventing simultaneous measurement of x and p. However, one can still infer the phase space distribution from measurements of only a single observable at a time and detect such negativities, thereby illuminating the failure of classical theory.
I think they showed this in Fig. 2.

Fine. However, here's the press release of this work. The lead author was interviewed, and said this:

Based on a series of experiments in the quantum optics laboratories, they examined the state of light. In classical physics, light possesses both an electric and a magnetic field.

“What our study demonstrated was that light can have both an electric and a magnetic field, but not at the same time. We thus provide a simple proof that an experiment breaks the classical principles. That is to say, we showed light possesses quantum properties, and we can expand this to other systems as well” says Eran Kot.
Electric and magnetic field? Not at the same time? What did I miss? The press release doesn't seem to have any resemblance (at least in terms of the experiment and what is being measured) with the actual paper. Can someone clarify this for me?

Zz.

Science Fiction, or Engineering Fiction?

The death of Ray Bradbury brings out the common assertion that science fiction stories, novels, etc. such as those produced by him and Asimov and others "predicted" various devices such as cell phones, ipods, etc... etc. In fact, when talking to many of my friends, they often brought up a number of the modern-day devices that had some sort of a resemblance to devices in use in various science fiction stories.

I've always considered these to be "technologies", rather than science. After all, these are gadgets. In fact, in the few (again, this may not be representative) science fiction stories that I've encountered, there is more of an emphasis on the engineering aspects of the "fiction" rather than science itself. After all, these are devices that have been engineered to do amazing stuff. So the engineering capabilities are the ones that are being touted, not the science. And strangely enough, the science that usually accompany these amazing devices aren't that "sexy". After all, when was the last time the front page of a major newspaper proclaim the physics that is responsible for the capacitive touch screen on your iPhone? So, if one wants to claim that the science that made these devices possible is also astounding, I would ask "what science"?

And this brings us to really glaring omission in many of the coverage of articles on science fiction stories. The science is often missing or not well-highlighted. The few times that I think that I've seen a "science fiction" is in the dealing with worm holes and hyperspace. But even there, one often finds that it is the "gadget" or the space ship that gets center stage (again, engineering). But here, at least, you can see the direct connection between the device, and the science, and how the "scientific fiction" resulted in the device and the ability to do something. This is not often the case. More often than not, from my reading, it's the gadget that gets top billing, and the science is rather obscure.

I've often been asked why I don't normally read science fiction novels or books. I think people tend to think that if you're a physicist, then reading science fiction stories is almost a second nature. My usual reply here is that, I find more fascinating and mind-boggling SCIENCE (not engineering) in real physics than I can find in science fiction stories. Science fiction writers don't deal with CP violation, spin-charge separation, fractional quantum Hall effect, neutrino flavor mixing, etc.. etc. How about making use of the Luttinger Liquid property of spin-charge separation where a spy decompose himself into a series of signals in a 1D wire to avoid detection? He then transport himself to another location inside the 1D wire, where his charge and his spin moves with different dispersion rate and thus, cannot be detected easily. How's that for "science fiction"?

Zz.

Wednesday, June 06, 2012

Photos Of The Transit Of Venus

Hey, did you miss seeing the once-in-a-lifetime event yesterday of the transit of Venus across our sun? If you did, don't fret. NASA is providing photos of the event from Solar Dynamics Observatory spacecraft, which should be way better than seeing it from earth!

:)

Zz.

Tuesday, June 05, 2012

Teaching General Relativity To Undergraduates

Here's an article in this month's Physics Today on what is needed to teach General Relativity in an undergraduate physics curriculum. Not sure how effective it is, but it is certainly worth an attempt, I suppose.

{The PDF version of the article is available for free}

This is in line with Hartle's earlier  paper in AJP on teaching this same subject to the same group of people.

Zz.

Transit of Venus Today

Will you be observing the transit of the planet Venus across the sun today? If you are in certain parts of the world that will be able to observe such a thing, and you will be participating, I would love to hear from you on what you saw or did.

It will take a little less than seven hours for Venus to cross the disk of the Sun, with the entire transit being visible at latitudes above the Arctic Circle as well as in much of the Pacific Ocean, Australia, and eastern and central Asia. People in many other parts of the world, meanwhile, will have the chance to observe at least some of the event. In Western Europe, the final hour or so of the transit will be visible after sunrise on 6 June, whereas observers in eastern North America will be treated to the first two or three hours of the celestial phenomenon before the Sun sets this evening.
Zz.

Edit 5/6/2011: There is a collection of websites on the transit of Venus, ranging from the historical perspective to why it is important astronomically. Check it out.

Monday, June 04, 2012

Don't Stick Your Hand In The LHC

There's not much physics in this, but I suppose many people do ask what would happen if they stick their hands in the LHC beam.  This article tries to answer it, and it is accompanied by a video as well.

Another LHC researcher, David Goldfarb, says in the video that other experiments have shown beams like the LHC's punching holes through sheets of metal. The soft tissue of a human hand would present much less resistance.
The thing here is that, you'd be dead soon enough before you can actually get to do that. The radiation being emitted from the beam itself is enough to kill you. So before you even get to stick your hand there, since you have to get into the beam tunnel, you would have had lethal dose of radiation already by the time you get the opportunity to do your useless deed.

Zz.