Physics and Physicists

Accelerators For Baggage Scanners

2013-05-22T08:17:00.002-05:00

I've been doing my part in trying to convey the fact that the overwhelming majority of the applications for accelerators have nothing to do with particle physics. Here is another example, the use of accelerators to generate x-rays for baggage scanners.

Two SLAC physicists with decades of particle accelerator experience helped a Silicon Valley company design and build X-ray devices that scan cargo containers for nuclear materials and other hazards. A version of this screening system is now in commercial use, and on May 16, the company received national recognition for its successful development from the federal Small Business Administration.

There are a lot more examples of this that many of you come in contact with almost everyday. You use or come in contact with particle accelerators more often than you realize.

Also note that this is another example where research that was meant for the study of fundamental physics, found an application elsewhere as an off-shoot.

Zz.

"Ghostbusters 3" To Be Based On Physics Research?

2013-05-22T08:01:00.002-05:00

I'm trying very hard not to roll my eyes (it's getting difficult to pop them back into the sockets), but hey, if it is done tongue-in-cheek like the first movie, it might just be entertaining enough.

It appears that the new Ghostbusters movie will tackle spacetime, or at least, something that threatened our spacetime.

Dan Akroyd told the ever-famous radio personality about the story of Ghostbusters 3:

“It’s based on new research that’s being done in particle physics by the young men and women at Columbia University. Basically, there’s research being done that I can say that the world or the dimension that we live in, our four planes of existence, length, height, width and time, become threatened by some of the research that’s being done. Ghostbusters – new Ghostbusters – have to come and solve the problem.”

Oooookay! Another creation of black holes in a particle collider that could destroy our universe, perhaps?

It sounds like it could be a storyline for a Marvel movie. We'll just have to see how they play this out.

Zz.

What Is Supersymmetry?

2013-05-21T21:38:00.000-05:00

Here's a video "tutorial" of what Supersymmetry is.

Zz.

A "Quantum Micrsocope" To Look At The Hydrogen Wavefunction

2013-05-20T10:04:00.004-05:00

The hydrogen wavefuction is one of the few systems that we can solve analytically. That is why we teach them in undergraduate QM classes. Yet, the ability to actually view such wavefunction isn't trivial and is part of the fundamental aspect of QM.

This latest work looks at the nodal structure of a hydrogen atomic orbitals using photoionization. In the process, the authors have provided a significant step in developing a "quantum microscope".

Writing in Physical Review Letters, Aneta Stodolna, of the FOM Institute for Atomic and Molecular Physics (AMOLF) in the Netherlands, and her colleagues demonstrate how photoionization microscopy directly maps out the nodal structure of an electronic orbital of a hydrogen atom placed in a dc electric field. This experiment—initially proposed more than 30 years ago—provides a unique look at one of the few atomic systems that has an analytical solution to the Schrödinger equation. To visualize the orbital structure directly, the researchers utilized an electrostatic lens that magnifies the outgoing electron wave without disrupting its quantum coherence. The authors show that the measured interference pattern matches the nodal features of the hydrogen wave function, which can be calculated analytically. The demonstration establishes the microscopy technique as a quantum probe and provides a benchmark for more complex systems.

The link above provides free access to the paper.

Zz.

A Physicist Having A Yard Sale?

2013-05-20T09:38:00.002-05:00

You'd think that we physicists are immune to having a yard sale. That's the look that I got over the weekend when some people found out that I was a physicist.

Over this past weekend, I decided that I've had enough crap.... er ... stuff in the house that needs to go. So I decided to do a garage/yard sale, since that was the weekend that my city designated as our zipcode-wide garage sale days. I set up stuff very early on Friday, and it went through till mid afternoon yesterday.

So it is your typical yard sale in many ways - old stuff, used stuff, but also a few new stuff that never been opened. But I guess what made it rather unusual are all the science/math books that I had for sale. Some people who walked by the stacks of books did a double take when they see books on math, physics, spectroscopy, etc. A person even picked up the infamous Abromowitz and Stegun's "Handbook of Mathematical Functions", looked at me, and said "Really?!"

And I replied "Really!".

A few people inquired what I do for a living, and of course, many of them have never met a physicist (at least, not that they know of). A person even asked if I work at CERN! :)

Anyway, the 3-day yard sale weekend was tiring, but it was a lot of fun. Made more than $300 selling stuff that I no longer want. Whatever's left will be donated.

And no, the Abromowitz/Stegun book didn't get sold, as with the rest of the math/science books, even though I was selling them for 50 cents a piece! If you are in the Chicago area, look out for those on sale at your nearest charity resell stores in the near future!

Zz.

From CERN To Goldman Sachs

2013-05-16T08:02:00.001-05:00

When I read this article, my first reaction was "Is this new?"

This news article is describing the case of a CERN physicist being hired by Goldman Sachs, thus changing his career from high energy physics (presumably) to quantitative finance.

Ryan Buckingham, a particle physicist with a PhD from Oxford University, spent three and a half years at CERN before joining Goldman Sachs in London as an associate in the credit and mortgage structuring team earlier this month. He declined to speak to us and Goldman didn’t return our request for comment, but it seems that the path from CERN to investment banking is a well trodden one.

“CERN is the place to find top PhDs in physical sciences and computing,” said Dominic Connor, head of quantitative finance recruitment firm P&D Quant Recruitment. “Working at CERN is one step up from having any old PhD. There a lot of people who have doctoral degrees, but you know that if someone has worked at CERN they will be very good indeed.”

Buckingham isn’t the only CERN alumni working in finance. Alexey Afonin, a vice president in strats and modelling at Morgan Stanley used to work there too. So did Anne Richards, the chief investment officer at Aberdeen Asset Management. So did Nikolaos Prezas, a quantitative researcher at J.P. Morgan and plenty of others. Most people seem to work at CERN early in their careers, and then move into finance.

Which is the reason I am puzzled at why this latest "acquisition" by the financial world making it into the news. Especially here in the US where funding for high energy physics is so crappy, a lot of PhDs in this field have to go look for employment elsewhere. Most of the people who work at CERN are not guaranteed at a long-term employment. Postdocs, for example, don't get to stay for as long as they want. And with their knowledge in statistical analysis and computational analysis skills, it is not a surprise that the field of quantitative analysis would swallow these people up.

Zz.

Neil deGrasse Tyson Prefers Star Trek Over Star Wars

2013-05-15T12:25:00.002-05:00

Hey, you can't win 'em all.

Famous astrophysicist Neil deGrasse Tyson, in an interview, indicates that he prefer "Star Trek" over "Star Wars" because, in his own words, Star Wars "... made no attempt to portray real physics. At all.... "

Don't shoot me, I'm only the messenger.

You can read and hear the rest of the interview at the link above.

Zz.

The Future Of Fermilab

2013-05-14T08:57:00.002-05:00

A video of a briefing to the community of the future of Fermilab. Here is the synopsis accompanying the video:

On Thursday, May 9, 2013, Fermilab invited elected officials and leaders from local communities to hear Director Pier Oddone lay out his vision of the laboratory's future. The presentation was held in Wilson Hall, and included both short-term (NOvA, Muon g-2) and long-term (LBNE, Project X) experiments, as well as an overall look at the direction of the laboratory's impact on Chicagoland. For further information on these projects see www.fnal.gov, http://www-nova.fnal.gov, http://muon-g2.fnal.gov, darkenergysurvey.org, http://lbne.fnal.gov, http://projectx.fnal.gov

It is interesting that Pier Oddone is presenting HIS vision of the lab future, considering that he is leaving Fermilab! :)

Still, with the dismal funding of high energy physics in the US, the future of Fermilab is really uncertain at this point. Many of the long-term projects being presented do not have a certain funding picture yet.

Zz.

"Einstein's Planet" Discovered

2013-05-14T08:00:00.000-05:00

There's nothing special about this planet, other than the claim that it was discovered using Einstein's Relativity concepts. However, there appears to be slight error in this news report:

The researchers capitalized on subtle effects predicted by Albert Einstein's special theory of relativity to find the planet. The first is called the "beaming" effect, and occurs when light from the parent star brightens as its planet tugs it a nudge closer to Earth, and dims as the planet pulls it away. Relativistic effects cause light particles, called photons, to pile up and become focused in the direction of the star's motion.

"This is the first time that this aspect of Einstein's theory of relativity has been used to discover a planet," research team member Tsevi Mazeh of Tel Aviv University in Israel said in a statement.

Additionally, gravitational tides from the orbiting planet caused its star to stretch slightly into a football shape, causing it to appear brighter when its wider side faces us, revealing more surface area. Finally, the planet itself reflects a small amount of starlight, which also contributed to its discovery.

Not to be nit-picky (well, I guess I am!), but this sounds like it is relevant to the GENERAL theory of Relativity, rather than just the Special theory of relativity. I guess I will have to wait for the paper to appear (unless the preprint are floating around already) to confirm this.

Zz.

You Can Teach Yourself To Think Like A Scientist - Part 3

2013-05-11T10:40:00.000-05:00

{You Can Teach Yourself To Think Like A Scientist - Part 2}

This entry deals with two separate issues, but both are related to the same 'event'.

In Part 2, I stated the technique of going back to the central, generalized principle. People often state their reasons for their actions or decision because they are abiding by some general principle. Realizing what this general principle is is crucial because it often clarifies the boundary of the argument, and one can also use that as a counter argument if the principle is not applied consistently.

In this part, I will attempt to show a specific example, and application, of this technique. Furthermore, I will also use the example to change the subject a bit (thus, the two separate issues) and presumptuously tell you how you should elect your political representatives. Yes, I know how pompous that sounds.

Let's start with the first part, which is applying the technique of investigating the generalized principle. During the height of the last US Presidential election, Senator Marco Rubbio of Florida was, at some point, considered as a potential vice presidential candidate for the Republican party. He wasn't, of course, but he is still in the US Senate. So who he is and what he stands for are still relevant. During this period of active political event, GQ magazine conducted an interview of Senator Rubio. One of the questions asked caught my attention:

GQ: How old do you think the Earth is?

Marco Rubio: I'm not a scientist, man. I can tell you what recorded history says, I can tell you what the Bible says, but I think that's a dispute amongst theologians and I think it has nothing to do with the gross domestic product or economic growth of the United States. I think the age of the universe has zero to do with how our economy is going to grow. I'm not a scientist. I don't think I'm qualified to answer a question like that. At the end of the day, I think there are multiple theories out there on how the universe was created and I think this is a country where people should have the opportunity to teach them all. I think parents should be able to teach their kids what their faith says, what science says. Whether the Earth was created in 7 days, or 7 actual eras, I'm not sure we'll ever be able to answer that. It's one of the great mysteries.

OK, so before I apply the "look for the general principle" method, let's get this very clear. If he is referring to Science, there are NO multiple theories on the age of the universe, and there is no issue at all on the age of the Earth. While there may be some uncertainty in the EXACT age (as is the case when we produce numbers for quantity such as this), we certainly are NOT making a mistake between 6000 years, versus 3 billion years! We do not make such magnitude of errors, and there's nothing to suggest that we are off by that much! It is not a great mystery.

So now, let's get back to applying the general principle argument. Reading his response, what kind of "general principle" is he abiding? I can see at least a couple: (i) he lives by the principle that if he isn't qualified in something, he then has no answers to questions in that area, nor does he have a strong-enough opinion about it to answer such questions; and (ii) if an issue isn't related to our "economic growth", he isn't interested in it or does not think that it is that important to receive an answer.

OK so far? Did you see anything else that we can extract as his overriding general principle?

So now, as we did in Part 2, let's adopt these two principles, and see what consequences they lead us to.

1. No qualification or expertise in an area, so don't have any answers, or won't answer, or don't have any strong opinion.

Now, this is strange. Senator Rubio has a law degree (like many politicians in the US). So his area of expertise is actually rather narrow. Does that mean that he only has an opinion in the area of law and nothing else? Does that mean that he won't answer questions about other issues, or can't make a decision on other issues? After all, he decides on stuff related to the US economy all the time. Is he claiming that he is an expert on various economic theories, ideas, principles, etc.? When he votes on the various bills and legislation, he obviously has opinions on those to arrive at his decisions. Is he then an expert in those areas?

Of course, things don't work that way. Politicians have staffers who are supposed to do the dirty work and research things. At some point, they also have people who advise them on issues. I'll deal with this more in detail later on. However, in this part, I'm pointing out the absurdity of not answering the question simply because he is claiming that he is not an expert (not a scientist) to answer that question. Yet, other questions where, presumably, he does not have an academic expertise in, are answered. This is another example of selective application of a general principle.

2. Not interested in issues unrelated to the "economic growth".

Apply this principle, we would expect Senator Rubio to abstain from voting on issues such as gay marriages. After all, what possible significant "economic growth" impact can that have? So has he disqualified himself in dealing with such issues throughout his political career?

The inconsistent application of the general principle is very common, especially in politics. People justify their actions by appealing to some general principle that they live by. When you understand what that principle is and state it in its direct form, you can then apply it, and see how, in many instances, they ignore that principle. As I had mentioned in Part 2, this means that there is often a more overriding principle that they are not stating, or trying to hide.

So now comes the related by separate issue part. I mentioned in #1 that politicians have to decide on a lot of issues, and practically all of them are outside of their area of expertise. This is where it matters to consider how they decide what opinion to listen to. Sen. Rubbio may not be a scientist, but does he listen to the consensus of scientists regarding the age of the earth? He appears to know about the biblical age of the universe, so why didn't he say "I'm not a theologian. I'm not qualified to answer that question". He didn't say that. Instead, he qualified that he's not a scientist. Does that mean that he will accept the opinions of scientists, even if it contradicts his biblical understanding? After all, he is implying that to be able to answer such a question, one needs to be a scientist.

There is also a puzzling effect here if one examines this closely. There are things we expect almost everyone to know, not because they are "experts" in such-and-such a field, but because as a citizen of the world, and as a citizen of a particular country, there are just certain level of knowledge that everyone is expected to know. What if I asked Sen. Rubio to point on a map the location of Washington DC, or Afganistan? Is he going to say he can't answer it because he's not an expert in geography? There are just things that we expect people to know. Sen. Rubio may not be scientist, and he may not know the scientific consensus of the exact age of the earth, but he should be AWARE of the orders of magnitude, and also the widely-conflicting discrepancy between that, and his biblical understanding. Maybe he's afraid that the interviewer would ask him how he would deal with such discrepancy, so he chose not to answer that question. Is this better than answering that he knows the scientific and biblical age of the earth, and is aware of the discrepancy? Personally, I prefer the latter. Simply not answer the question by claiming that he's not an expert makes him appear to be ignorant of something a knowledgeable person should know. Do we want an ignorant to be our political representative? I'd rather have someone who has the knowledge, and who is aware that there are discrepancies between what he "accepts" as part of his beliefs, versus what is accepted by experts in a certain areas. It is like being an alcoholic. You have to be aware of the problem FIRST before you seek help. If you deny there is a problem, you won't become better. Ignorance is not bliss.

So how am I telling you how to elect your political representatives? First of all, I will immediately tell you that my suggestion will never work and will never take hold. Very few people will agree with this methodology because most people will NOT vote this way.

Most of us choose our political candidates to vote for based on his/her stand on various issues. Maybe there are one or two issues that we consider to be extremely important, and so, we tend to prefer candidates who happen to also have the same opinion as us on those issues. We may overlook other smaller, less important issues that those candidates may or may not have the same opinions as us. But what it boils down to is that we choose candidates based on their agreement with what we believe in or what we feel strongly about. In other words, we want someone who holds our opinion on certain matters.

I consider this to be a very poor way of electing a political official. When someone is elected to a political office, he/she is faced with many different scenarios, variations, events, etc. that often change over time. Market crashes, war happens, disasters occur, etc. What looks good back during a political campaign may not look good now, especially in the climate of politics where you are dealing with other politicians, and with the progression of time and other events, even outside of one's country or immediate area. To rigidly hold on to some issues often does not work, and what end up happening is that most politicians have to compromise somewhat in varying degree to try to get the job done. This is why we then accuse them of "lying" to us, because they had to renegade on their promises to do certain things. We tend to hold them to the items they promised, rather than hold them to do their jobs, which is to take care of the country in the best way they know how.

So I propose that we elect politicians not based on what they believe or based on the compatibility of their opinions, but rather on their ABILITY TO THINK!

Now, think about it for a second. It is a revolutionary concept! :)

I want someone who has a rational and sensible way to think things through. I want someone who knows that when he/she doesn't know something, he/she would find reputable sources to learn about those things. I want someone who has the analytical ability to know that he/she is using some general principle, and to be aware when he/she isn't being consistent to those principles. I want someone who has the analytical ability to analyze a problem, who where to seek knowledge and information, and then find a sensible solution. Nowhere in there is there any requirement that this person agrees with my opinion on this or that.

This elected person will be faced with a mountain of issues, and often, things come up very unexpectedly. Many things occur that cannot be predicted. I want someone who has the ability to evaluate all of these, to analyze them systematically, to seek proper advice and sources, and then to arrive at a decision. I do not want someone who is stuck and rigid with a certain ideology, while the rest of Rome is burning down around him/her. The inability to think and rationalize a problem systematically means that decision that comes out of this person may easily be flawed.

This is why I'd rather Sen. Rubio said that he knows about the scientific age of the universe, and is aware of the discrepancy between his Christian beliefs and the scientific facts. It would have shown that he is a man of knowledge, and that he is not ignorant. It shows that he is aware of the issues, and it is something he hasn't reconciled yet. I'd rather have someone like that, who obviously have thought of things, rather than someone who ignores things but STILL has no qualms on making decisions based on things he/she doesn't know much about.

But of course, this will never happen.

:)

Zz.

Edit 5/16/2013: It appears that Sen. Marco Rubio must be an expert in biometric scans, because he didn't hesitate to give his opinion on the matter, if we were to apply his principle:

Sen. Marco Rubio, a Gang of Eight member who voted for the amendment, expressed his disappointment after the senators rejected the proposal. “Immigration reform must include the best exit system possible because persons who overstay their authorized stay are a big reason we now have so many illegal immigrants,” his statement read. “Senator Rubio will fight to add biometrics to the exit system when the bill is amended on the Senate floor. Having an exit system that utilizes biometric information will help make sure that future visitors to the United States leave when they are supposed to.”

Intro Physics Lab Data Analysis

2013-05-10T06:46:00.001-05:00

So bear with me. I'll explain the point of this trivial-looking exercise at the end.

A student is given a circuit containing a variable power supply, a resistor, and an ammeter all in series, and a voltmeter attached across the resistor. The student is then asked to determine, as accurately as possible, the resistance of the resistor.

Knowing that Ohm's Law stated that V=IR, the student made a series of measurement of potential difference (V) versus current (I) on the resistor. The student end up with this data set:

Using Ohm's Law, he knows that the slope or gradent of PD versus I will give him the resistance of the resistor. He then enters these numbers into his data analysis program, runs a linear line fit routine, and it spits out the value of the slope that he wants, which is ~0.4 Ohm.

Sounds alright, doesn't it? However, there is one MAJOR problem with this. Can you describe what it is? You may assume that the voltmeter, ammeter, and power supply are "ideal", meaning they do not contribute to the accuracy or inaccuracy of the measured values.

So, I gave that as a trivia quiz on Physics Forums a few weeks back. I'll provide the answer below, so if you want to work it out yourself before looking at the answer, don't scroll down any further.

A quick glance at the plotted data reveals that it is not a straight line. Fitting a straight-line to those data does not make an accurate representation of the behavior of the data. So the data analysis is faulty. Applying V=IR in this case is no longer valid since there is no longer a linear relationship between V and I, with R being a constant.

There is a long story associated with this, and why I asked this question. When I was a lab TA during my graduate school years, we had a typical lab on finding the spring constant using a set of weights. One time, I added a second spring that was deformed to each group's equipment and required that they try to find the spring constant of that as well. Well guess what? Most of the students in the class simply dumped the data into the linear regression program, let it spew a result, and that's that, regardless of the fact that if they examine the plot, they would see that the relationship between F (applied mass on the spring) and x (extension of the spring) was no longer linear! Only a few of the students actually commented in their report on this.

The moral of the story here is that the software you use can do many things, and it WILL spit out a number for you. However, it doesn't mean that that number has any meaning or is a valid result based on the relationship shown in the data.

Zz.

The Higgs Boson And Our Life

2013-05-08T14:47:00.002-05:00

What is the impact of the Higgs boson on our lives? Good question.

This is a video of a seminar given by Fabiola Gianotti of CERN, who is the spoke person for the ATLAS collaboration.

Zz.

Pear-Shaped Nuclei Hint At Physics Beyond The Standard Model

2013-05-08T14:34:00.003-05:00

Just in case people forget that CERN (and also the LHC via predominantly the ALICE detector) can also do nuclear physics experiment, here's a new report on the study of the shape of heavy nuclei that might provide hints at physics beyond the Standard Model.

Although there was some limited evidence for pear-shaped nuclei in experiments carried out on radium-226 and neodynium-148 in the 1990s, neither study was conclusive. What Peter Butler of the University of Liverpool and colleagues in Belgium, Finland, Germany, Poland, Spain, Switzerland, the UK and the US have now done is to find strong evidence for octupole transitions in radon-220 and radium-224. These transitions are a sign that the nuclei are lopsided and appear in the spectrum of gamma rays these nuclei emit as they decay from an excited state.

I'm sure that this is just the very beginning of this line of inquiry.

Zz.

Is The Wavefunction Real?

2013-05-07T16:25:00.001-05:00

This is a rather lengthy article on PhysicsWorld that has a good coverage of the ever-present question on whether the solution to the Schrodinger equation - the wavefunction - is real, or not. It covers the latest status in this investigation with the PBR theorem.

A good "general" article if you are interested in such things.

Zz.

Combing the LHC Data For Hints Of Something Beyond The Standard Model

2013-05-06T10:35:00.001-05:00

With the LHC in shutdown mode right now, one would think that everyone involved in the major detectors are taking a holiday. Not so. In fact, it appears to be a very intense period of data combing. The accumulated LHC data are being carefully examined to look for hints to indicate new physics beyond the standard model. The article linked above describes this hunt. However, it also describe other important discoveries made at the LHC beyond just the Higgs, which did not make the headlines in the popular media and the public.

Those waiting for new physics can take comfort in the fact that the LHC has achieved far more than the discovery of the Higgs over its three-year operation. A year before the Higgs's detection, for instance, the ATLAS experiment found another new boson: the so-called Chi-b(3P) quark-antiquark pair. That was followed by the discovery last year of a new excited Xi(b) baryon by CMS. Although not elementary particles like the Higgs is thought to be, Chi-b(3P) and Xi(b) have helped tie up some of the Standard Model's loose ends by confirming the nature of the strong force, which binds quarks together.
Perhaps more important than these particle discoveries, however, have been the LHC's precise measurements of existing Standard Model phenomena. Some of these are quantities that cannot be accurately predicted, such as the high-energy structure of the photon that is being studied by the ALICE experiment. But other measurements can put the latest theories to the test. These include the energy distribution of particle jets (which are produced when quarks collide), and the production rate of pairs of heavyweight elementary particles such as W and Z bosons (which carry the weak force, responsible for radioactive decay) and top quarks. "Those calculations have been taken now to a higher degree of precision," says Incandela. "We have a very good match between our data and our simulations, which tells you that our calculations are very good."

So there is clearly a lot of things that have come out of the LHC that have advanced our knowledge of elementary particles. This is not a one-trick pony machine.

Zz.cer

April 24, 2012 Gamma Ray Burst

2013-05-06T07:45:00.001-05:00

I don't know how long these Opinion pieces are available for viewing on CNN webpage (very often, these articles are gone after a few months and the link I often use are dead). So you should read this (and save it if you wish) as soon as you can.

This is a rather clear and concise reporting on the recent, puzzling gamma ray burst, discovered this year on April 27. For an article written for CNN, this is a rather good science report, but then, it wasn't written by some reporter who simply understood it by hearing or reading other 2nd hand material. It was written by a physicist from Yale. So I must commend CNN for actually finding someone with a high level of expertise to write and report on something like this. Other news outlets should learn from this.

Zz.

Neils Bohr Between Physics And Chemistry

2013-05-05T08:00:00.000-05:00

If you had missed this free article from month's issue of Physics Today, well then, don't miss it. It deals with Neils Bohr model of the atom, and how that contributes to chemistry and physics.

Zz.

LHC Through Google Glass

2013-05-04T08:32:00.004-05:00

Here's a short video of a view of the LHC through Google Glass. You may follow his blog in the link below.

http://agl-initiatives.org/teaching-with-glass/

Zz.

Commonly Mispronounced Name Or Phrase In Physics

2013-05-03T15:36:00.002-05:00

Do you know of any commonly mispronounced name or phrase in physics? I know of a few. Many of these are often names in another language, such as French. So many in the English-speaking world, especially here in the US, often tend to pronounce these words the way they are spelled, rather than the way they should be pronounce in their native tongue. Even the popular name of "Einstein" is commonly mispronounced when compared to what it should be in German.

Here is my list that I can think of off the top of my head:

1. Brillouin
2. Auger
3. Double Chooz.

I may come back later and add more to this list.

Zz.

Vacation

2013-05-03T14:36:00.001-05:00

I've been on vacation. Did I miss any big physics news? :)

It'll take me at least through the weekend to catch up. It is tough to get back to speed after powering down for several days.

Zz.

Female Physicists Doctoral Experiences

2013-04-26T10:56:00.000-05:00

I haven't had time to read this paper in its entirety, but that should not prevent me from highlighting it here. You should be able to download the paper for free.

Abstract: The underrepresentation of women in physics doctorate programs and in tenured academic positions indicates a need to evaluate what may influence their career choice and persistence. This qualitative paper examines eleven females in physics doctoral programs and professional science positions in order to provide a more thorough understanding of why and how women make career choices based on aspects both inside and outside of school and their subsequent interaction. Results indicate that female physicists experience conflict in achieving balance within their graduate school experiences and personal lives and that this then influences their view of their future careers and possible career choices. Female physicists report both early and long-term support outside of school by family, and later departmental support, as being essential to their persistence within the field. A greater focus on informal and out-of-school science activities for females, especially those that involve family members, early in life may help influence their entrance into a physics career later in life. Departmental support, through advisers, mentors, peers, and women’s support groups, with a focus on work-life balance can help females to complete graduate school and persist into an academic career.

Zz.

Secrets Of The Dark Universe: Simulating The Sky

2013-04-25T08:02:00.002-05:00

I'll post the synopsis to this video, which you can also read on YouTube:

An astonishing 99.6% of our Universe is dark. Observations indicate that the Universe consists of 70% of a mysterious dark energy and 25% of a yet-unidentified dark matter component, and only 0.4% of the remaining ordinary matter is visible.

Understanding the physics of this dark sector is the foremost challenge in cosmology today. Sophisticated simulations of the evolution of the Universe play a crucial task in this endeavor.

This movie shows an intermediate stage in a large simulation of the distribution of matter in the Universe, the so-called cosmic web, accounting for the influence of dark energy. The simulation is evolving 1.1 trillion particles. The movie shows a snapshot of the Universe when it was 1.6 billion years old.

While this video may be obvious to people in the field, it would be nice if they had some narration to accompany each scene so that we know what we are looking at! After all, they went to all this trouble to make a visual representation of the simulation and posting it on YouTube for the public to see. Might as well put a little bit more effort in telling us what each of those different scenes are. Otherwise, all we see are cool images without learning anything much.

Of course, the physicist in me would like to know what kind of parameters were used, what are the assumptions, where was this/will this be published, etc. Y'know, the mundane stuff! :)

Zz.

You Can Teach Yourself To Think Like A Scientist - Part 2

2013-04-24T10:57:00.000-05:00

{You Can Teach Yourself To Think Like A Scientist - Part 1}

OK, I'm trying to pick up this series again, hopefully with less typos and grammatical errors (hey, you have to expect these things especially when many of my blog entry are written on the fly).

The idea behind this series is to emphasize the notion that many of the decisions on how we live and behave are due to how we arrive at certain ideas or knowledge. I truly believe that the more we realize that we need to use the same scientific methodology in arriving at decisions and actions that we do everyday, the better off we are.

It has been raining a lot in the Chicago area the past couple of weeks. I was in a friend's vehicle during one of a rainy period, driving to somewhere. He had his windshield wipers on, and driving rather slowly. I told him that he could speed it up a little so that we get there faster. He told me he is just abiding the law, and driving just below the speed limit that was posted. I told him if he was so concerned about abiding the law, why didn't he have his headlights on? He had no answer.

{Here, in Illinois, the law says that when you have your windshield wipers on, you must have your headlights on as well}

One of the things I see very often here is that people often justify their actions because they are following some more generalized principle. In the example I relayed above, my friend was living by the principle of "abiding the law". A consequence of living by this principle is "driving under the speed limit". But as we all know, there are OTHER CONSEQUENCES of the principle of "abiding the law". I mentioned one of them, "wipers on, lights on". Yet, my friend didn't do this, and chose to ignore it, without any explanation.

So now, we are left to speculate on why that is. Is he truly living by the principle of "abiding the law"? Or is he really living by the principle "abiding by the law that I find convenient and the one that I remember"? If he is doing the latter, then simply espousing the idea that he is living by the principle of "abiding the law" is highly inaccurate. If you live by a certain principle, then you must follow and do all that principle asks you to do. You cannot pick and choose. If you do, you are no longer living by that principle, but rather, living by a modified form of that principle. This, you must clarify or you are conveying the wrong information.

In physics, any general idea, principle, or theory has a body of outcomes and consequences. Special Relativity, for example, makes many different predictions. Each one of them must be tested and confirmed. If any of the predictions and consequences do not match experimental observations, then (i) either the theory is wrong or (ii) there's new physics beyond what that theory can predict. We simply cannot pick-and-choose. This means that if something doesn't work all the time, we must know clearly where that boundary is, and this must be made very clear so that people know that beyond this boundary, it no longer works.

To think like a scientist in this case is to make a clear analysis on what the general principle is that people are using to justify their actions or arguments. You need to sit back, and figure out if what someone is arguing is based on some central principle or belief. Let's apply it to a hot topic of the moment, the debate on gay marriages. It is a hot topic here in the US at the moment, and it is certainly is one in France right now.

One of the most common argument against gays, and against gay marriages, that I've heard is that it is "not natural". Some of these people tried to "intellectualize" the argument against it by taking out the religious aspect of it, and using Mother Nature as the argument. So let's apply our analysis that I stated above. What is the overriding principle involved here? Of course, it is the principle of living "naturally", obeying what is natural, or opposing what is "not natural". Let's look at this critically.

First of all, what actually is meant by "natural"? Is it what would happen if left on its own without human intervention? Is it what can be found in nature without any artificial means or intrusions? Let us adopt both.

If these people are living by the principle of upholding what is "natural", then:

1. Does that mean that everything that is natural is OK and can be practiced by human beings? This includes animals eating and devouring their youngs that they know won't survive, and having multiple sexual partners, which is prevalent in the animal world.

2. If they are opposed to everything that is not natural, then they should also question other unnatural human behavior, such as clothings, shaving, circumcision (now what could be more unnatural than cutting off a piece of one's body?), etc.

Yet, these people who opposed gay marriages on the grounds that it is "not natural" (the principle involved here) do not oppose other unnatural aspects of human life. So are they like my friend who drove very slow, but chose to ignore turning on his headlights? Are they arguing against something "not natural", but with caveats? Are they closer to living the principle of "I oppose things that are unnatural, but only limited to my own personal dislike of certain behavior". Or maybe "I oppose things that are unnatural that are dictated by my religious beliefs. Other unnatural things are fine."

Either one of those will be significantly more accurate than simply stating that one is opposed to something because it is "not natural". The reason why this must be made explicitly clear is that knowing what principle is involved provides a very well-defined boundary condition and playing field. You clearly know that this really isn't JUST about something being unnatural. There are other factors involved. The analogy to physics is that this isn't just a simple trajectory motion. Other external factors such as wind resistance is involved. So the discussion (or arguments) can be framed within such boundary conditions. That other person is arguing against something based on a number of factors, not just because it is "not natural", the same way my friend was driving slow not just because he's obeying the law.

And interestingly enough, I find that some of the people I talked to, often do not realize this aspect themselves. In other words, those who opposed gay marriages by using the argument that it is "not natural", often truly believe that that is all the reason for such opposition. Like my friend, when I asked them whether they also oppose circumcision and wearing of clothing, and shaving, they looked at me funny. It often never occurred to them that there are other unnatural human behavior, and yet, these never bothered them. What is happening here is that they never examined ALL the consequences and outcomes of adopting such a principle. They never carefully thought through what other unnatural behaviors and practices are out there. Just because wearing clothes is normal, it doesn't mean it is natural. Just because one is familiar with something doesn't make it "natural", based on our definition above. Just like my driving friend who never considered the fact that living by the principle of abiding the law means that one has to abide by ALL the laws, these people also never made such consideration of living their lives without anything "not natural".

In physics, knowing what the general principle is is extremely important. It is the origin and the source of many other things, and we understand the limits, the boundaries and what can and cannot be done based on that overriding principle. A lot of arguments that I've seen among the public and in politics are often arguments of the consequences of such-and-such a principle. Some politicians want to cut spending because they live by the principle of "small government" or some other things. Yet, if you examine carefully, the principle that they live by are not well-defined, and more often than not, they adopt it inconsistently, applying it here, while ignoring it there - cut spending and budgets for science funding, social programs, etc, while continue to increase military spending (drive under the speed limit, but ignore to turn on the headlights).

My personal diagnosis on all of this is that, many people FIRST adopt the CONSEQUENCE (i.e. oppose gay marriage, oppose funding social programs, don't want to drive fast), and THEN went back and find some general principle to justify their position (not natural, want to cut spending, want to follow the law). Now, there's nothing wrong with that. It is done in science too. In physics, we tackled problems such as the Blackbody radiation, which then eventually led to a more general principle of quantum mechanics. Only later on, do we realize that the blackbody radiation is a consequence of QM. But once QM has been formalized, we adopt ALL of QM as we learn more and more about it. We continue to test it, and explore the boundary of its applicability.

Unfortunately, this is not true in the cases of human decision that I've stated above. There was never any self-diagnose of one's adoption of some overriding principle. Those who adopt the opposition to things that are "not natural", never examined if they are opposing ALL of things that are not natural, because they are not! My friend never examined if he truly is living by the principle of abiding the law, because he wasn't.

So the central principle of this entry is the examination and the consequences of a central principle. Isn't that neat? :)

Zz.

APS April Meeting Plenary Session Videos

2013-04-23T10:37:00.006-05:00

In case you didn't attent this year's APS April meeting, the plenary session videos are online.

http://www.aps.org/meetings/april/events/plenary.cfm

Zz.

"Do You Read Science Fiction Books?"

2013-04-21T10:02:00.001-05:00

I wrote a while back on one of the most frequent question that I get asked once people find out that I'm a physicist. "Do You Watch "The Big Bang Theory"?" is one of them. The one other most common question: do you read science fiction books? They think that since I deal with a lot of science, then reading science fiction would be almost second nature.

Simple answer: I don't!

First of all, I seldom read fiction books. I seldom read books anymore, actually. I just can't have any long-term relationship with a book of any kind. I do so much reading in a day, the last thing I want to do when I wind down is read some more. So putting in a lot of time to read and finish a novel is not my idea of a good time.

Secondly, while I know of many scientists who enjoy reading science fiction novels, and many find them "stimulating", I don't. This is because I often find it a bit annoying that that some parts of logic, reality, and even some aspects of physics is "bastardized" to such extent. I suppose it is my problem that I simply can't let go of reality when I try to read such novels. While I do enjoy watching sci-fi movies, I find them to be more of an entertainment for a couple of hours, view them more for the story than for the accuracy. The exception being some of the more awful sci-fi movies that simply makes no sense and force you to suspend logic and reality way too many times.

Lastly, many of the sci-fi novels tend to use the more "sexy" aspects of physics, but they miss many more fascination parts that do not get wide press coverage. This is where I find stuff in physics a lot more imaginative and a lot more fascinating than even some of the most outlandish imagination in sci-fi. The concept of "phase coherence" is a conerstone in quantum mechanics. But has it been used and depicted in sci-fi novels? Or what about the fact that in 1D conductors, the many-body effect of spin-charge separation would cause a "particle"'s spin and charge to move separately?

These are details that those who are not in physics would not have understood, and thus, unable to exploit. Yet, to me, they are extremely fascinating. If I were a sci-fi writer, I could make one heck of a story using those principles alone.

As imaginative as sci-fi stories are, I find actual physics to be significantly more fascinating. So kids, that is why I don't really read science fiction books.

Zz.