Tuesday, August 31, 2010

2009 US Physics Department Roster

The AIP has just released the latest 2009-2010 academic year roster for the Physics Departments at US institutions. Both the number of physics bachelor degree granted continues to increase.

The number of physics bachelor’s granted continues to climb, with 5,908 degrees in the class of 2009. As physics undergraduate enrollments continue to increase, bachelor’s production will also see increases. PhD’s are also on the rise with 1,554 conferred in the class of 2009.


Science Fights Back Against A Homeopath Fight-Back

I read this blog entry, and I find the same fight that I've been waging against physics quacks. And since this is a truly wonderful argument against a pseudoscience, I am more than happy to give this blog entry ample air time on here.

This is a response to a response. The author had thoroughly argued against a peer-reviewed paper that purportedly claimed to have seen a positive impact of homeopathy. Both the author, and another, have severely criticized the paper for several shortcomings. But it appears that these criticisms irked a writer at a homeopathy website (surprise!). What you can read is not only a rebuttal, but also a very pointed attack against pseudoscience in general.

The issue that keeps coming back is the fact that many people cannot tell the difference between anecdotal evidence and scientific evidence. They also cannot reason why an anecdotal evidence is insufficient to claim validity of something. To me, that is the fundamental reason why we are having this discussion, and on why pseudoscience flourishes.

It would be interesting to see if this paper will get a ton of rebuttals in the coming months.


A "Designer Universe" Created By Mortals Like Us?

This is a rather interesting and certainly provocative piece by John Gribbin. In it, he is pushing out the idea that our universe could have been by a designer - but not a 'god' - that is not too far from us, using nothing more than a giant particle accelerator!

The black holes that could be created in a particle accelerator would be far smaller: tiny masses squeezed into incredibly tiny volumes. But because of gravity's negative energy, it doesn't matter how small such holes are: they still have the potential to inflate and expand in their own dimensions (rather than gobbling up our own). Such expansion was precisely what our universe did in the Big Bang, when it suddenly exploded from a tiny clump of matter into a fully-fledged cosmos.

You have to read the entire article to get the full picture. For me, it makes for a very good science fiction novel or movie. Again, there's nothing here that we can rule out as being impossible, but is it probable?


Monday, August 30, 2010

"Misconception About Science" Seminars

The public often complains that they do not have access to many scientists, and are not given proper guidance and education about science issues. This actually isn't true unless one expect things like this to be spoon-fed. A little bit of effort is involved, including finding proper resources on the web.

Still, there are efforts to educate the public, and this is one just respectable endeavor. A series of seminars on popular misconception about science will be held at the Appalachian State University campus in North Carolina, starting from Sept. 14 and will run till Dec. 9. A look at some of the topics that will be presented makes this sounds very interesting:

Sept. 14—“Hypotheses, Theories, Laws and Facts in Science: What’s the Big Deal and Why Should You Care?”
Sept. 30-“Science, Pseudoscience and Junk Science: How Knowing the Difference Between Good and Bad Science is Important for Maintaining a Scientifically Literate and Democratic Society,”

If you are in the neighborhood, this would be a good thing to attend.

Saturday, August 28, 2010

On Vacation

I'm on a short vacation, so probably no new updates until Monday. In the mean time, keep those nominations coming for our contest to select the Most Attractive Physicist. I've been quite impressed by the nomination so far.


Wednesday, August 25, 2010

The Last Leg Of The Alpha Magnetic Spectrometer Saga

{Reminder: We have an ongoing nomination for the Most Attractive Physicist contest. Submit your nomination today!}

In the continuing saga of the alpha magnetic spectrometer, it is now being transported from CERN to the shuttle where, hopefully, it will get to be lifted to the space station. We hope that this will mark the end of its painful saga to be deployed, and the beginning of the science that it promises to produce.


Tuesday, August 24, 2010

High Heels, Physics, and Finance

While we have seen Physics and Finance being mixed, it isn't everyday that we see high heels and physics being mentioned in the same breath. But that's what is happening in this profile of a physicist who have made that jump into the world of finance, but still try to retain some feminine quality.

At work, Debbie Berebichez is a quantitative risk analyst. On her own time, she's the Science Babe. She's also an inspiration to young women interested in righted-brained careers, including finance.

It's good that, even though she has left the science world, she is still dedicating her effort towards encouraging more female into science. The timing of this article is also rather appropriate, because I'm in the middle of running the contest to find the most attractive physicist. Wonder if someone will nominate this "science babe"? :)


Joe Biden Will Speak on Stimulus Impact on Science and Technology

At 11:45 am US Central Time, US Vice President Joe Biden, will speak on the impact of the American Recovery and Reinvestment Act on innovation, science, and technology. You can view the speech at http://www.whitehouse.gov/live.


Monday, August 23, 2010

Probing The Order Parameter Of Cuprate Superconductors

{Reminder: We have an ongoing nomination for the Most Attractive Physicist contest. Submit your nomination today!}

This is an utterly comprehensive review of the study of the order parameter of the cuprate high-Tc superconductors using SQUID microscopy. It is written by one of the world's foremost expert in this topic, so if you have any interest in how we know the gap symmetry for this family of superconductor, this is a review article that you won't want to miss. The wealth of the reference materials alone is a sufficient reason to keep a copy of this article.


Sunday, August 22, 2010

The Most Attractive Physicist Contest!

Yes, folks, If you are looking for deep, profound physics issues, this blog post is NOT IT! :) I've decided, for this one post, to be shallow, perky, and superficial! After all, we know that such characteristics are what draws in the attention of the public and politicians! So I've decided to become just that!

I had a discussion with a friend regarding my post on the fact that I don't "look" like a physicist, at least, to many people who didn't have an a priori knowledge of my profession. In all my years of interacting with other physicists and scientists in general, there certainly is a type of "look" that one would associate with a physicist. I don't mean the absent-minded, hair-sticking-out-in-all-direction, socks-don't-match type of look. That's too stereotypical and inaccurate. I'm talking about the look of "intelligence", some might even called "dignified", and maybe even a few thick glasses here and there, that many people associate with being a physicist. But this also does not cover everyone. One would be very surprised to learn (or maybe not) that there are physicists, both men and women, who are quite attractive. I mean, there are those who could easily grace the covers of Vogue, GQ, etc. In fact, in my post on The Science Channel silly "documentary" on the Big Bang, I commented on the fact that the host of that show, physicist João Magueijo, might be one of the most attractive physicists that I've seen. And anyone who has met Lisa Randall would have to admit that she is also very easy on the eyes.

So there's ample evidence there that there are physicists, both male and female, who clearly tip the scale in terms of attractiveness. So what about this contest? Ah, this is where we dive into the depth of the world of superficial. I want to have a contest where we nominate the physicist who we think is attractive, and then we all vote on them! How much fun is that? :)

So here are the rules:

1. Anyone can nominate a physicist who he/she thinks is a candidate for being the most attractive. The deadline for nomination is Sept. 15, 2010.

2. You may nominate as many as you want. HOWEVER, you should include either a picture, or at least a link to a picture, so that the voters have an idea what this physicist looks like. The links can also be videos, etc., i.e. anything to give the rest of us a good idea on this person's feature. This will be useful especially if it is someone who is not a household name.

3. You may nominate someone based on his/her attractiveness at a different age. For example, the Albert Einstein who worked at the Swiss Patent Office may be more attractive than the one that landed at Institute for Advanced Study in Princeton. So if you are nominating Einstein in his younger years, you have to accompany that nomination with a picture of him in that age.

4. If you are submitting someone who isn't a household name, it would also help that you include a link to show that this person is a physicist. A link to either a paper, or university position, etc. would be sufficient. But how do I define a physicist, you ask? To me, anyone with a physics degree, even if that person isn't a practicing physicist, qualifies! I may have to contact you if I can't verify a nominee's credentials.

5. Don't be afraid to nominate yourself, if you are a physicist, and if you think you might qualify as being attractive. Or nominate your colleagues, with their permission, of course! I want as many good-looking physicists as I can get for this contest.

6. Submit your vote by adding a comment to this blog post. If you do not wish to have your nomination made public, please clearly indicate as such and your nomination will not be released (all comments to this blog are moderated and will only be made public upon release by me).

7. At the end of the nomination period, I will tally up all the nomination, and will select the Top 5 the male and a separate Top 5 for the female physicist.

8. I will then open up the voting to all readers of this blog, so YOU get to choose who you think is the most attractive male and female physicist. I haven't decided yet on what I'll do if we end up with a tie, so I'll just make things up as I go along if that happens.

So off we go!!

Edit: Nomination period is now over. No more nominations please. New comments submitting nominations will not be approved, not because I disagree, but I don't want to include it on here so that I won't be confused on who got nominated when.


Friday, August 20, 2010

Mary J. Blige Teams With NASA To Promote STEM To Women

Kind of an odd pairing, but maybe it'll work, or at least, draws attention.

Superstar Mary J. Blige has teamed up with NASA to promote more women into STEM careers. Here's a brief synopsis accompanying the video:

In this second of two public service announcements, award-winning recording artist Mary J. Blige appears with veteran NASA space shuttle astronaut Leland Melvin to encourage young women to expand their career choices by studying science, technology, engineering and mathematics (STEM). Both PSAs are now on NASA TV and the agency's website at: http://www.nasa.gov. NASA's Summer of Innovation (SoI) project and Blige's Foundation for the Advancement of Women Now (FFAWN) both show students the many possibilities available if they follow their dreams and reach for the stars


Thursday, August 19, 2010

Transforming Students' "Common-Sense" Beliefs Into Newtonian Thinking

I've sometime been given an argument that such-and-such is correct because ".. it makes sense...", as if the human concept of things that makes sense is perfectly valid. My argument is that "common sense" is nothing more than an accumulation of knowledge. There will be things that won't make sense to someone who hasn't had that particular knowledge.

I was reading this article in Phys. Rev. Special Topics - Physics Ed. Research. In it, the authors were studying the effectiveness of a particular teaching technique - the Just-In-Time teaching - in correcting the students' "common sense" understanding of motion and kinematics mechanics[1]. But what drawn my interest more was the background info that I've been meaning to read, but only until now did I had a chance to actually read (quickly) them, thanks to the references given in this article.

The first paper that I wanted to read was something I've encountered many times already in many of these educational research papers: the Force Concept Inventory[2]. The link should give you an online copy of the paper. But another interesting paper is the one by Halloun and Hestenes titled "Common sense concepts about motion"[3]. Here, they pointed out several erroneous "beliefs" of many incoming college students about basic kinematics.

(a) On the pretest (post-test), 47% (20%) of the students showed, at least once, a belief that under no net force, an object slows down. However, only 1% (0%) maintained that belief across similar tasks.

(b) About 66% (54%) of the students held, at least once, the belief that under a constant force an object moves at constant speed. However, only 2% (1%) held that belief consistently.

(c) About 65% (44%) of the students exhibited, at least once, the belief that an impetus is required to maintain the motion of an object. About 40% (24%) were consistent in that belief. About 37% (15%) maintained, at least once, that the trajectory of an object depends on an impressed impetus, but only 3% (1%) were consistent in this belief. Students with quasi-Newtonian beliefs were far more consistent than the other students.

Strangely enough, some of the students still tried to hang on to their faulty beliefs even when faced with an observation/experiment that clearly contradicted those beliefs.

During the interviews with several of the students, typical classroom demonstrations were given of the physical situations described in a few of the talks on the diagnostic test. The demonstrations appeared to have no more effect on their opinions than mere discussions of the phenomena. As a rule, students held firm to mistaken beliefs even when confronted with phenomena that contradicted those beliefs. When a contradiction was recognized or pointed out, they tended at first not to question their own beliefs, but to argue that the observed instance was governed by some other law or principle and the principle they were using applied to a slightly different case.

Quite an entertaining reading. I would imagine that these things would be something an caring instructor would want to know, i.e. the state of mind of the students in the class, to be an effective instructor.


[1] S.P. Formica et al., Phys. Rev. ST Physics Ed. Research v.6, p.020106 (2010). Papers in this journal are open access, you may obtain a copy of this paper here.
[2] D. Hestenes, et al., Phys. Teach. v.30, p.141 (1992).
[3] A.B. Halloun Am. J. Phys. v.53, p.11 (1985).

Pressure-Driven Competition of the Electronic Order Can Increase Tc in the Cuprates

A rather interesting paper that appeared in Nature this week. The authors studied the trilayer Bi2223 by observing Tc, the critical temperature, as they increase the pressure on the material[1]. [Side note: trilayer Bi2223 is called that because it has 3 copper-oxide planes per unit cell.] The interesting thing is that they first noticed an increase in Tc with increasing pressure, but then it started to drop before increasing again, to a maximum of around 136 K at 34 GPa.

The explanation given here is that Tc is first determined by two temperature scales: the critical temperature of pairing, i.e. when the Cooper pairs start to form, and the critical temperature for phase coherence, when all the pairs become "stiff" from phase fluctuation. This last part is when one gets the long-range phase coherence in a superconductor.

But it gets more interesting than that. It appears that with increasing pressure, one gets more hole doping onto the two outer copper-oxide planes. These two outer planes start to become more doped with holes and thus, might actually have a higher Tc, while the center copper-oxide plane remains underdoped. This is what the authors called "... The natural appearance of an inhomogeneous charge distribution among the inner and outer CuO2 planes...."

It is certainly an interesting proposal for a possible increase in Tc for these material.


[1] X.-J. Chen et al., Nature v.466, p.950 (2010).

Tuesday, August 17, 2010

Why Econophysics Will Never Work

First we have the issue of the debate about the differences between Economics and Econophysics. Then there's an argument on why Economics will never be like Physics. Now comes an argument on why Econophysics will never work!

The markets are not physical systems. They are systems based on creating an informational advantage, on gaming, on action and strategic reaction, in a space that is not structured with defined rules and possibilities. There is feedback to undo whatever is put in place, to neutralize whatever information comes in.

The natural reply of the physicist to this observation is, “Not to worry. I will build a physics-based model that includes feedback. I do that all the time”. The problem is that the feedback in the markets is designed specifically not to fit into a model, to be obscure, stealthy, coming from a direction where no one is looking. That is, the Knightian uncertainty is endogenous. You can’t build in a feedback or reactive model, because you don’t know what to model. And if you do know – by the time you know – the odds are the market has changed. That is the whole point of what makes a trader successful – he can see things in ways most others do not, anticipate in ways others cannot, and then change his behavior when he starts to see others catching on.

It will be interesting to see if the writer has actually read Christophe Schinckus AJP's paper (my guess is he hasn't), and if Schinckus has a response to this.

The question whether something works or is valid in field of studies such as economics, social science, politics, etc. is rather interesting. In the physical sciences, there's usually no ambiguity because we can either test it out, or go look for it. Something works when what it predicts can be observed and reproducible. So how does one determines if the various principles and models in economics, social science, politics, etc. are valid and do work? Simply based on previous data and observation that somehow fit into the model? But as this writer has stated, there's no model to fit because the model keeps changing due to such model-changing feedback. It appears that the whole field is more based on "intuition" than on any rational reasoning.

If that's the case, then it truly isn't a science but more of an art. So why do people who graduate with a degree in economics, social "science", or politics, sometime get a "Bachelor of Science" degree?


Monday, August 16, 2010

A New Source of CP Violation?

CP-violating events seem to be a more frequent news lately. We just had, earlier this month, the observation of CP-violation in the leptonic sector for the first time. Now comes a more convincing evidence of CP-violation in dimuon systems. This is an excellent and well-written review of the two relevant papers from the D0 collaboration at Fermilab. Not only that, you also get free access to the two papers in question.


Can Science And Religion Exist Side-By-Side?

The more I read this article, the more annoyed I got. The writer is arguing that science and religion can co-exist because (i) they are both "religions" and (ii) they should stick to within their own boundaries where each of them works best.

He listed what he called as the "similarities" between religion and science:

Both have ubiquitous entities that permeate everything. In religion it is called a god, in science a force. If one wants to know the entity, in religion one prays to find out the "will" of god, while in science, one does experiments to discover the "properties" of the force.
When I read this, I scrolled to the bottom of the page to see if it listed the credential of the writer, and it did. "Wolfgang Baer teaches graduate-level courses in Monterey and received his doctorate in physics from the UC Berkeley...." No! He has a Ph.D in physics and still thinks that science cares more about discovering the properties of "the force"? What force? In QM, there's no "force". In fact, in classical mechanics, one can use the Hamiltonian/Lagrangian approach and not deal with forces at all!

And oh, let's not forget one GLARING fact here. In religion, there is no one unique god! In fact, there could also be multiple gods in the same religion! In physics, when a concept is accepted, no matter what religion, society, economic background, social standing, etc. you come from, you use the SAME, IDENTICAL principle! In other words, we all agree on the physical formalism!

Both have the nasty habit of defending embarrassing facts by turning them into features.

How embarrassing is Mary's conception until it is turned into further proof of God's divine intervention? How embarrassing is our inability to predict the trajectory of an individual electron until uncertainty is elevated to become the cornerstone of modern physics by Heisenberg's Uncertainty Principle.
This is puzzling. The fact that we have particle accelerators clearly shows that we CAN predict the trajectory of an individual electron. That's how we can design such accelerators. But if the writer is invoking QM and the superposition principle that's inherent in phenomena such as the double slit, then he has it all wrong. This is NOT a matter of physics not being able to predict such a trajectory. It is rather that this is what nature is! Unless he is claiming that there is an underlying description of the physical world that physics either does not understand or have no access to, then he is making an a priori assumption that is based on no physical evidence.

Not only that, since when is the HUP become the "cornerstone of modern physics"? The HUP, despite its name, isn't a "principle". It is a CONSEQUENCE of how we define observable operators and wavefunctions in QM. In other words, many of us use it as a back-of-the-envelope type calculation and very seldom (I don't know of any) use it as a starting point. It isn't that important as far as day-to-day "operations".

In religion, a divine intervention is called a miracle; in science it is called a singularity or an emergent property.

Er.. how is this even the same? A miracle has never been verified. Emergent properties have! Emergent properties just doesn't come out nowhere. Superconductivity didn't just appear for not apparent reason. We can also create those ON DEMAND. So when was the last time one can call in for a miracle?

He then described the "differences" between science and religion. I'll pick just one example here:

The logic of science and religion have opposite starting points, but neither is right nor wrong. The differing starting points are tailored to serve specific domains of applicability. Science has clear advantages in supporting engineers to build and control machines, while religion has advantages when dealing with the human experience of feelings and emotions.

When we apply these belief systems beyond their domain of applicability we run into trouble. Few would seriously pray to God to direct the trajectory of a bullet instead of taking careful aim along the sights. Science clearly dominates in this application.

However, consider a priest who is called to the bedside of a dying patient to provide comfort and hope with a tale of everlasting life. Compare this with a medical establishment that plasters the patients with tubes, needles, and an irrational fear of dying when there is not a shred of scientific evidence that the "first person I" ceases to exist simply because body functions stop. This is like concluding the radio station is dead because one's receiver box quit.

Wow! Where should I even start?

He seems to think that there's a clear boundary between issues that are within the domain of religion, and issues within the domain of science. This is obviously wrong! Religion cannot help but describe the physical and natural world and offer explanations for them. The Genesis is nothing but the creation of the universe and human beings! So he wants cosmology and physics and biology to stay out of such topics? Or does he want the Genesis to be removed completely from the Bible? After all, there is a clear overlap here!

Secondly, he is implicitly invoking the "god of the gaps" here. Here's arguing that where science broke down and offers no explanation, this is where religion comes in. Baloney! Back in the dark ages, there are many phenomena that science and rational understanding could not explain. Various gods and spiritual explanations were used to explain those things, ranging from eclipses, the flooding of the Nile, the explosions of volcanoes, etc. If we buy into this writer's argument, since religion is already the explanation for such things, science has no business going into such areas. But it did and showed why and how these things have a natural and rational explanation. The "god of the gaps" has been shrunk, and continues to shrink. Science may not have any "tale of everlasting life", but this is not a criticism about science. It is more of a criticism about religion for perpetuating such Santa Clause-equivalent to the dying. If all we care about is sedating a dying patient, I hear that morphine can do as good of a job without lying to the patient.

The one thing about science is that we ACKNOWLEDGE the deficiencies and things we do not fully understand. In fact, that is why we continue to have employment in science. Scientists, by definition, studies things that we do not understand, look into new things, and tries to find explanations for things we don't know about. No such thing exists in religion. Scientific knowledge expands and changes as we know more and more. This is not true for religions. Religion, by definition, is "perfect"! When was the last time you hear any preacher preaching things about the various things that his/her religion can't do, or don't have an understanding of, or can't explain? There are so many things stated as FACTS in religions, and even when there's contradiction between religion and science, many still cling to the religious description even when there isn't any shred of evidence to support that.

I don't know what his definition of existing "side-by-side" really means, but I can see both of them existing in separate, parallel universe! :)


Sunday, August 15, 2010

The Doppler Effect Explained

This is a rather informative article out of MIT that is suitable for everyone. If you are ever curious on how astronomers can tell what elements are present in stars that are very far away, and how fast that celestial body is moving, this article will give you a good general idea on how such a determination is made.

In astronomy, that source can be a star that emits electromagnetic waves; from our vantage point, Doppler shifts occur as the star orbits around its own center of mass and moves toward or away from Earth. These wavelength shifts can be seen in the form of subtle changes in its spectrum, the rainbow of colors emitted in light. When a star moves toward us, its wavelengths get compressed, and its spectrum becomes slightly bluer. When the star moves away from us, its spectrum looks slightly redder. 


I Don't Look Like A Physicist

Hum... maybe I don't look "smart" enough for people to think I'm a physicist. Or maybe I dress and act "differently" than what people envision a physicist should look and behave.

I've gone to many social events, and even hosted many myself, where I interact with a lot of people from many different backgrounds. In my "obsession" with my other hobbies, I often mingle with a wide variety of people and have lots of fun. Inevitably, once you get a conversation going and people start being interested in you, the question on "what do you do for a living" comes up. When I tell them I'm a physicist, it never fails to generate a surprise, and often followed by a subsequent interest in a number of things, such as:

1. What exactly do you do?
2. Where do you work?
3. Are you creating black holes?
4. Do you blow things up?
5. Do you smash particles?
6. Do you work with nuclear bombs?
7. Do you work at Fermi?
8. What are they doing at that big particle accelerator?
9. etc.

I suppose such reaction is because of the obvious. One doesn't encounter a physicist that often in real life. Almost everyone gets their impression of what a scientist or physicist looks like from TV and movies. But I think, in my case, there's an "added bonus". I don't think one expects a physicist to have an obsession with "Disney", or to actually enjoy shopping for clothes and home furnishing/accessories! :)

But there's another twist to this as well. Those who do know me already and aware that I'm a physicist, often are surprised at some of the other things that I can do, as if being a physicist renders me socially incompetent, can't dress properly, and have no sense of style. When I bought a new home recently and furnished it myself, I invited friends over to the new digs. People were thoroughly surprised at the decor and that how good it looks. In fact, I've had more than a few comments telling me that if my job as a physicist doesn't work out, I should seriously consider interior decorating! I'm not sure if I should take that as a compliment or not! :)

So maybe I don't look like a physicist and don't behave as one in the social setting. But maybe, that is simply another "barrier" and misconception we have to break about people in this profession.


Friday, August 13, 2010

When Nitrogen Attacks

I posted several fun videos out of Jefferson Lab that presented a number of rather interesting and educational experiments and observations. See Balloons and Liquid Nitrogen, and Radioactive Half-Life Experiment. Well, those fun and crazy folks have posted a video of their bloopers!


Thursday, August 12, 2010

CP-Violation For Neutrinos

I'm a bit late in reporting this, but better late than never.

It appears that there's a first sighting of possible CP-violation in the lepton sector. An analysis of the MiniBooNE experiment seems to suggest that the flavor oscillation for neutrino and antineutrino differs from each other.

A team of physicists including some from MIT has found surprising differences between the flavor-switching behavior of neutrinos and antineutrinos. If confirmed, the finding could help explain why matter, and not antimatter, dominates our universe.

“People are very excited about it because it suggests that there are differences between neutrinos and antineutrinos,” says Georgia Karagiorgi, an MIT graduate student and one of the leaders of the analysis of experimental data produced by the Booster Neutrino Experiment (MiniBooNE) at the Fermi National Accelerator Laboratory.
 This would be very exciting indeed.

Still, I'm going to nitpick this report a bit for a possible misleading information.

Neutrinos, elementary particles generated by nuclear reactions in the sun, suffer from an identity crisis as they cross the universe, morphing between three different “flavors.” Their antimatter counterparts (which are identical in mass but opposite in charge and spin) do the same thing.
 If you read this carefully, you'll get the impression that antineutrinos are counterpart to neutrinos (which is true), and have opposite charge and spin. Of course, this would be in error because neutrinos are neutral. The passage is describing "antimatter" in general, but the way it is written makes it sound as if this is a description of antineutrinos. If someone who didn't know any better understood it that way, then he/she will become confused later on when the article gets it right:

In an effort to help nail down the number of neutrinos, MiniBooNE physicists send beams of neutrinos or antineutrinos down a 500-meter tunnel, at the end of which sits a 250,000-gallon tank of mineral oil. When neutrinos or antineutrinos collide with a carbon atom in the mineral oil, the energy traces left behind allow physicists to identify what flavor of neutrino took part in the collision. Neutrinos, which have no charge, rarely interact with other matter, so such collisions are rare.
 Communicating to the public is a very tough task where our words and how we convey the message can make a difference. Hopefully, this apparent contradiction doesn't diminish the message. This comment is not really a criticism of the article. It is easy to do such a thing, and I know I've done it myself where I know what I intended to write, but it came out differently after I've written it.


Wednesday, August 11, 2010

BCS as Foundation and Inspiration: The Transmutation of Symmetry

This is Frank Wilczek's contribution to a volume on the 50th Anniversary of the BCS theory. It shows clearly the connection and influence of this amazing theory to the rest of theoretical physics.

The influence of BCS theory on the broader discipline of theoretical physics has been no less profound. Two key ideas abstracted from BCS theory, that have been widely transplanted and borne abundant fruit, are pairing and dynamical symmetry breaking. Pairing was an essentially new idea, introduced by Cooper and brought to fruition by BCS. The symmetry breaking aspect was mostly implicit in the original BCS work, and in earlier ideas of Fritz London and Landau-Ginzburg; but the depth and success of the BCS theory seized the imagination the theoretical physics community, and catalyzed an intellectual ferment. The concept of spontaneous symmetry breaking was promptly made explicit, generalized, and put to use by several physicists including Anderson, Josephson, Nambu, and Goldstone. The flexibility and transformative power of these ideas revealed itself gradually, in applications to phenomena that at first sight appear to have little or nothing in common with superconductivity.


The Physics of Weight Loss

I thought I'd post a link to this article about simple, basic, physics on weight loss. Although one can quibble a bit about 'arguing with Newton', I would say that nothing in here is surprising as far as the physics is concerned.

And we are all governed by the prevailing laws of physics that relate matter and energy. Calories are a measure of energy, and matter cannot be created without energy input. Arguments against the fundamental role of energy balance in weight regulation -- against calories in versus calories out -- are arguments with Isaac Newton. Folks, nobody wins an argument with Isaac Newton!
There are, once we are done growing up, three ways we burn calories: physical activity, the generation of heat and just existing. There are technical terms for the second and third: thermogenesis, and resting energy expenditure (sometimes referred to as basal metabolic rate). What should be noteworthy right away is that you are not in charge of two out of the three!

You can choose how much exercise to do. But you don't get to choose how thermogenic you tend to be, and that can matter quite a lot. Like exercise, thermogenesis accounts for roughly 15 percent of total energy expenditure on average, but there is lots of variation on the theme of average. People who generate more heat from calories have fewer available with which to make fat. They tend to be people who can eat a bit more, and stay thin anyway.

 There ya go! That's your health info for the day! :)


Tuesday, August 10, 2010

Precision Tests of Gravity

This is a wonderful overview (or "Resource Letter" as it will be called when it is published in AJP) of the test of General Relativity written by Clifford Will.

Abstract: This resource letter provides an introduction to some of the main current topics in experimental tests of general relativity as well as to some of the historical literature. It is intended to serve as a guide to the field for upper-division undergraduate and graduate students, both theoretical and experimental, and for workers in other fields of physics who wish learn about experimental gravity. The topics covered include alternative theories of gravity, tests of the principle of equivalence, solar-system and binary-pulsar tests, searches for new physics in gravitational arenas, and tests of gravity in new regimes, involving astrophysics and gravitational radiation.


Monday, August 09, 2010

A Brief Review of Atoms .... After A Flirt At A Supermarket

I initially didn't know what to make of this. It started out with a story of an 8-year old calling the woman behind him "old". I think most men would get a slap on the face for doing that. Still, it turned into a rather humorous flirting.

And if you can get past that, there's a rather concise description of atoms, especially the role of neutrons in atoms! I suppose the "connection" here is that both the boy and neutrons are "social butterfly".

Er..... oookaayyy.....

I'm guessing that this is part of a series, and this is one of the middle article.


Sunday, August 08, 2010

Physics Abuse So Bad, It Is Hysterically Funny

When I was in my undergraduate years at UW-Madison, there was this show late at night that telecast really, really bad movie. I mean, we're talking about monster movies so bad, some time those that need to be voice-over, the dialog not only didn't match the mouth, it some time didn't even match the gender of the actor! The tag line for the TV show was "The moves are so bad, they're good!"

This is the case here. I've always criticized those pseudoscience advocates who invoked physics as justification or evidence that the garbage they are pushing is valid. Inevitably, they bastardized what little physics they thought they understood, especially their superficial understanding of QM. Now, this time, the bastardization comes in from a different angle. Here, physics is being used in a rather hilarious fashion either as an explanation, or as an analogy, to issues on ..... get this .... RELATIONSHIPS! I kid you not.

There are just things that simply don't make any sense. For example:

When I graduated high school, I had speed. I was going somewhere, just not sure which direction. By and large my relationships were similar, going somewhere but concentrated on self. In college, I like to think I got a little direction vector going in both my professional life and my personal life. I was learning about angular momentum but I just didn’t realize it. Instead of revolving around my own center of mass, I began to revolve around another.

So just what is this angular momentum? Momentum has a specific physics definition involving an equation I’d like to gloss over. We can usefully think of it as energy in a direction. A vector direction. The angular part comes in when this energy in a direction is going around and around another object. Even if it travels at a constant speed it’s always accelerating since the direction vector is always changing.

It's time to nitpick. I don't need to have something going "around and around" to have an angular momentum. All I have to show is that L = r x p (where L is the angular momentum, r is the vector position of the object, and p is the momentum of the object {"x" is the vector cross product}) is not zero. This means that something moving with a constant velocity can have an angular momentum ABOUT A POSITION THAT ISN'T ALONG THE LINE OF MOTION. Such object isn't going "around and around" at all. Any undergraduate intro physics student would know this.

An example is the moon going around the earth. The moon has acceleration (both speed and direction), and it has the magic property of changing its vector of motion second by second as it curls around the earth. Because of the big difference in mass, the moon “feels” the earth more than the earth “feels” the moon, but both do feel each other. That’s angular momentum without an equation.

The moon feels the earth more than the earth feels the moon? Presumably, "feels" here corresponds to "force", then this person is violating Newton's 3rd law. Again, any intro physics student would have seen the force on the moon, due to the earth, is equal to the force on the earth, due to the moon.

Still, this is where it starts to get utterly nonsensical and becomes laughably funny.

I think in some relationships, both people may share the same velocity vector. Rushing through life in the same general direction. They are going parallel. But if they don’t start revolving around each other they never get to feel the angular momentum of each other. These relationships often fail since neither partner gets to feel the other’s angular force.

Do you feel my angular momentum right now? But oh, it gets better!

Another example of a relationship has one person unconditionally revolving around the other while the other simply continues in a straight line. Particularly damaging for the revolving partner, he or she never gets to feel the others angular force. These relationships often end in failure too.

Those poor atoms, they are such failures. Imagine these atoms, moving in all different directions, while those electrons revolving around their "partner", the nucleus. Those selfish nucleus never get to feel the electrons' angular force. Their relationships are heading towards probable failures!

After this, this writer completely lost me. Or maybe, he actually was completely lost in his elementary geometry class.

We have to do one quick math review. Remember in geometry and algebra we use Cartesian coordinates X, Y and Z. These were named after René Descartes, who is credited with inventing them in the 17th century. (he also founded analytic geometry, and is credited with the quote “Cogito ergo sum” — I think, therefore I am.) You might recall the X, Y and Z axis used to chart or plot equations in math class. Make a picture in your mind.

Lets pretend the woman has the X axis (appropriate chromosomally) and the man has the Y axis (also appropriate chromosomally). What happens when each revolves around the other? A new, magic force vector is produced, and it comes out their Z axis! If you want to see one of the Z axis products, observe closely the next little baby you see (ask permission). They are magic.

But you don’t have to be married or have a child to share your angular momentum. Examples of the Z vector force are the products of any loving relationship that involves shared angular momentum. The foundation and volunteer folks are familiar with these feelings. The hospice workers I know are chuck full of angular momentum. That’s how they can do such a difficult job. Magic.

Besides the fact that the x, y, and z axes are all mutually orthogonal to each other and thus, have no components/effect on the other axes, I was almost rolling on my floor at how bad this was! The best part is that if you do something in x, and your partner does something in y, one would expect that the resultant is a vector in the x-y plane. But no, you would be wrong! In this convoluted geometry, you produce an "off spring" in the z-axis!!! How much fun is that??!!!

OK, I need to get out of the house and find a hobby. I'm having way too much fun with nonsense like this.....


Saturday, August 07, 2010

What To Do With A Degree In Physics?

I've highlighted several articles on career paths of people with physics degrees, especially undergraduate degrees. This is another article from the UK that examines the same thing.

Physics is concerned with observing and understanding the natural universe. However, studying the subject will help you gain skills useful to many employers, not just in the science sector. You will be highly proficient at problem solving and have demonstrated your ability to solve challenges by thinking creatively. A physics degree will also give you a grounding in advanced mathematics. The practical skills gained through planning experiments will also be appreciated by recruiters.

This of course, is not surprising and nothing new. Other articles have mentioned something similar. It is consistent with previous entries on "What Does One "Do" With an Undergraduate Physics Degree?", and the most recent statistics for initial employment for physics B.Sc. degree holder here in the US.


Friday, August 06, 2010

"Simple" Projectile Motion Problem

I was reading the July 2010 issue of Physics Education, one of IoP journals, and came across this rather interesting, seemingly-simple projectile motion problem. Supposedly, this was taken out of Eric Mazur's "Peer Instruction" book. I will post the figure here:

The question is rather simple based on that figure. If the battleship simultaneously fires two shells at enemy ships and follow the shown parabolic trajectories, which ship gets hit first?

The question gives 4 possible answers: (1) Ship A, (2) Both at the same time, (3) Ship B, and (4) Need more information.

The level of physics needed to solve this is first year undergraduate intro physics, or even AP physics. It is how you approach the problem to solve this that may require a little bit of sophistication. See if you can find the answer, and I'll post mine in another blog post later... :)


Thursday, August 05, 2010

Failed Theories of Superconductivity

We always focus on what works and what became successful. But in getting there, there are many ideas and concepts that didn't work, and some that were just plain wrong. But all of these were important in trying to understand a phenomenon.

This is such a good paper to read. Joerg Schmalian has dug up and illustrated all the failed theories in trying to describe the phenomenon of superconductivity before the BCS theory came along. In the process, we realize how amazing BCS theory is for what it accomplished.

Abstract: Almost half a century passed between the discovery of superconductivity by Kammerlingh Onnes and the theoretical explanation of the phenomenon by Bardeen, Cooper and Schrieffer. During the intervening years the brightest minds in theoretical physics tried and failed to develop a microscopic understanding of the effect. A summary of some of those unsuccessful attempts to understand superconductivity not only demonstrates the extraordinary achievement made by formulating the BCS theory, but also illustrates that mistakes are a natural and healthy part of the scientific discourse, and that inapplicable, even incorrect theories can turn out to be interesting and inspiring.

You get a clearer picture of his intention in the introduction.

When discussing failed attempts to understand superconductivity, we must keep in mind that they are a natural and healthy part of the scientific discourse. They are an important part of the process of finding the right answers. These notes are not written to taunt those who tried and did not succeed. On the contrary, it is the greatness that comes with names like Joseph John Thompson, Albert Einstein, Niels Bohr, Léon Brillouin, Ralph Kronig, Felix Bloch, Lev Landau, Werner Heisenberg, Max Born, and Richard Feynman that demonstrates the dimension of the endeavor undertaken by John Bardeen, Leon N Cooper and J. Robert Schrieffer. Formulating the theory of superconductivity was one of the hardest problems in physics of the 20th century.

A highly recommended reading.


Wednesday, August 04, 2010

Beware of Green Laser Pointer

This is rather disconcerting.

A team at NIST has discovered a potential safety hazard with the increasingly-popular common green laser pointer.

Late last year, the research team purchased three low-cost green laser pointers advertised to have a power output of 10 milliwatts (mW). Measurements showed that one unit emitted dim green light but delivered infrared levels of nearly 20 mW—powerful enough to cause retinal damage to an individual before he or she is aware of the invisible light. NIST’s Jemellie Galang and her colleagues repeated the tests with several other laser pointers and found similarly intense infrared emissions in some but not all units.

The problem stems from inadequate procedures in manufacturing quality assurance, according to the research team. Inside a green laser pointer, infrared light from a semiconductor diode laser pumps infrared light at a wavelength of 808 nm into a transparent crystal of yttrium orthovanadate doped with neodymium atoms (Nd:YVO4), causing the crystal to lase even deeper in the infrared, at 1064 nm. This light passes through a crystal of potassium titanyl phosphate (KTP), which emits light of half the wavelength: 532 nm, the familiar color of the green laser pointer.

However, if the KTP crystal is misaligned, little of the 1064 nm light is converted into green light, and most of it comes out as infrared. Excess infrared leakage can also occur if the coatings at both ends of the crystal that act as mirrors for the infrared laser light are too thin.

You may read the full report at the link given in that press release.

This is a serious problem because your eye can't react to shield itself from IR until it is too late. For many people who do laser alignment, working with IR laser is one of the most dangerous endeavor, even with proper eye wear.

So if you have one of these green laser pointer, try testing it as described in the report to see if you have a dangerous level of IR from it.


Rumors Travel At The Speed Of Light

This NY Times news article looks at how science rumors can spread like a bush wildfire on the 'net, devouring all sense of credibility and standards.

One culprit here is the Web, which was invented to foster better communication among physicists in the first place, but has proved equally adept at spreading disinformation. But another, it seems to me, is the desire for some fundamental discovery about the nature of the universe — the yearning to wake up in a new world — and a growing feeling among astronomers and physicists that we are in fact creeping up on enormous changes with the advent of things like the Large Hadron Collider outside Geneva and the Kepler spacecraft.

I've mentioned this before with respect to the recent rumors of the Higgs. Even though this is only a blog and not a news source, I still refused to be suckered like other news agencies to report such rumors, especially when it came from a previously unreliable source. I mean, how many times do you have to get whacked on your head before you yell "Stop!"? Even when I'm reporting something that I've heard via 2nd hand news, such as the suicide at Fermilab, I would not have reported it had it came from someone's blog!

This is one downside of having such easy access to "information" and communications. News spread very fast without regards to accuracy. One must always keep that in mind.


Monday, August 02, 2010

God of Quantum Flapdoodle

I like that name "quantum flapdoodle". Supposedly, it was coined by Murray Gell-Mann to describe "..stringing together a series of terms and phrases from quantum physics and asserting that they explain something in our daily experience.." In this article, Michael Shermer continues to rebutt Deepak Chopra and his quantum flapdoodle.

Chopra believes that the weirdness of the quantum world (such as Heisenberg’s uncertainty principle) can be linked to certain mysteries of the macro world (such as consciousness). This supposition is based on the work of Roger Penrose and Stuart Hameroff, whose theory of quantum consciousness has generated much heat but little light in scientific circles.
Inside our neurons are tiny hollow microtubules that act like structural scaffolding. Penrose and Hameroff conjecture that something inside the microtubules may initiate a wave-function collapse that leads to the quantum coherence of atoms, causing neurotransmitters to be released into the synapses between neurons. This, in turn, triggers the neurons to fire in a uniform pattern, thereby creating thought and consciousness. Since a wave-function collapse can only come about when an atom is “observed” (that is, affected in any way by something else), “mind” may be the observer in a recursive loop from atoms to molecules to neurons to thought to consciousness to mind to atoms to molecules to neurons . . . and so on.
In reality, the gap between quantum effects and the world of ordinary events is too large to bridge. In his 1995 book The Unconscious Quantum, the University of Colorado particle physicist Victor Stenger demonstrates that for a system to be described in terms of quantum mechanics, its typical mass m, speed v, and distance d must be on the order of Planck’s constant h. “If mvd is much greater than h, then the system probably can be treated classically,” that is, according to the physical laws discovered by Newton. Stenger computed the mass of neural transmitter molecules and their speed across the distance of a synapse, and he concluded that both are about three orders of magnitude too large for quantum effects to be influential. It is important to note one very common practice with physicists, and scientists/engineers in general. When one makes off-the-cuff supposition, one can make quick back-of-the-envelope calculations to figure out not if something is possible, but if something can be ruled out immediately simply based on what we know. So such a thing that Vic Stenger did in calculating the mass and speed of a neural transmitter may not be accurate, but it is of the order-of-magnitude value that clearly shows that quantum effects are just not significant. This is part of science. This is something people like Chopra can't do and have no skill to do. They typically make handwaving argument with no quantitative analysis to back what they say. Yet, they claim to base their speculation on science/physics.

One would think that, since they're making things up as they go along, that they could make their own reality and use that, rather than piggybacking onto something they clearly do not understand.