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

{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

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

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

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?

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

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

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

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

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

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

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

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

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

{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

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?"

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.

Self-Assembling Nanoparticles

This is a video showing nanoparticles self-assembling into a larger structure.



This brings me to a related topic on evolution. One of the arguments that I often hear from those who oppose the concept of evolution is the idea that the probability of life occurring out of this random mess is extremely small that it should have never happened. Thus, the idea out of evolution that we call came about due to this random formation of life in the beginning, and then slowly evolve over time, can't be correct.

The few so-called estimates on the probability calculation that I have seen never ever mentioned, or take into account, something that many of us in condensed matter are aware of, which is this very fact that there are phenomenon of self-assembly of atoms and molecules. We know this happens. Each time we have ice crystals, or see naturally-formed quartz, etc., those are naturally-occurring self-assembly. What are the odds of those things being formed simply via random arrangements or capture of atoms? The fact that they do form, and form pretty frequently, means that the phase-space for that happening isn't that small, and actually is quite high.

So I can't help wondering if that such self-assembly, especially when there is a change that causes a form of phase transition, might play a role in the formation of life or single-celled form of life. And because of that, the chances of it happening isn't as small as it is made up to be.

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Let's Measure the Diameter of the Sun

Hey, Forstbite Theater is back! In this video, they show a demo on how to measure the diameter of the sun.




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Parallel Universes: Many Worlds

Here is Minute Physics take on the 'ever popular' Many Worlds/Parallel Universes picture of quantum mechanics. While this view may make it easier to digest certain conceptual issues of QM, it also creates a whole slew of other issues that I find hard to swallow. As is the case, you might solve one, while creating other set of messes.




As an experimentalist, until there is an ability to test one versus the other, I'll stick to the "Shut up and calculate" view. It is less stressful! :)

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Peter Higgs: In His Own Words

Here's a fascinating interview with the man of the moment, Peter Higgs.

1. He got into theoretical physics because he was "incompetent" as an experimentalist:

That sort of set the scene for me and when I chose to go to university, which was Kings College London, I continued to show all sorts of symptoms of incompetence in the lab while I was a student there. So very early on, I was heading towards the theoretical end of physics as the only kind of thing I was competent in.

2. He thinks that the field that has been named after him should have been called the Goldstone field instead:

It shouldn't be a Higgs field. If it's anybody's it should be Goldstone field, I think. When Nambu wrote his short paper in 1960, Jeffrey Goldstone of Cambridge University, who was visiting Cern, heard about it. He then wrote a paper which was conceptually similar to what Nambu had done, but a simpler model.

3. He doesn't like the name "god particle". In fact, I know of no physicist who does!

That name was a kind of joke, and not a very good one. An author, Leon Lederman, wanted to call it 'that goddamn particle' because it was clear it was going to be a tough job finding it experimentally. His editor wouldn't have that, and he said 'okay, call it the God particle', and the editor accepted it. I don't think he should've have done, because it's so misleading.

4. He thinks, as I concur, that the LHC should have sold itself in a broader term, rather than being popularized as a machine to look for the Higgs. As I've said many times, no one and no institution would fund something THIS expensive just to do ONE thing.

I was a bit unhappy about the way it was being sold. Not because I didn't think they should go after the Higgs Boson, of course, but I thought they should have educated people more about the breadth of the programme of the machine, and not concentrated on this so much. It seemed to me they were taking a risk that when they found the thing, then a lot of people would say 'oh well, that's it, isn't it? Why do we still want this machine?

5. His reaction to the announcement at CERN that the Higgs might have been found:

I didn't accept it was me that they were cheering. I regarded it as cheers for the home team, as at a football match, and the home team were the two experiments, Atlas and CMS, with 1,500 members each. That's what it was really about. Maybe they were cheering me too but that was a minor issue.

Don't miss an earlier spotlight on Peter Higgs that has a bit more in-depth coverage of the history leading up to the formulation of the Higgs field.

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Possible Detection of WIMPs?

A preprint that was just released from the CDMS collaboration indicates a strong possibility of detection (finally!) of WIMPs. which is a candidate for dark matter.

You can also read a press coverage of this here.

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Fair-Sampling Loophole Closed

Another Bell-type experiment out of the Zeilinger's group, and this time they have effectively closed the fair-sammpling loophole in this experiment.

This kind of tight monitoring is important as it closes an important loophole. In previous experiments on photons, there has always been the possibility that although the measured photons do violate the laws of classical physics, such non-classical behaviour would not have been observed if all photons involved in the experiment could have been measured. In the new experiment, this loophole is now closed. "Perhaps the greatest weakness of photons as a platform for quantum experiments is their vulnerability to loss – but we have just demonstrated that this weakness need not be prohibitive," explains Marissa Giustina, lead author of the paper.

I will not be surprised if we will soon see in one experiment where ALL the loopholes are closed simultaneously.

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Lasers

Another video out of JLab, and this time it is on lasers.

However, this video only describes the different types of lasers, and says nothing about the principles behind it. It didn't even describes what a free-electron laser is, even though the person in the video works with FEL. Too bad!




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Fund Me, Maybe

OK, so I may be late getting to the party, since this video obviously has gone viral without my knowledge of its existence till recently (thanks to Lavabug at Physics Forums). Still, if you haven't seen it, it is hysterical.

From the description, the video footage was captured during the 221st meeting of the American Astronomical Society in Long Beach, CA.



With the US Science budget in the dumps during this budget sequestration, maybe all of us need to make such a video!

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Recent Physics PhDs - Skills Used and Satisfaction With Employment

The AIP has released its latest statistics on recent PhDs. This one is from the graduating class of 2009 and 2010, meaning that these people graduated and entered the job market at the height of the economic meltdown. This survey asked about the skills used in their jobs, and the level of satisfaction in those jobs.

The non-surprising aspect here is the set of skills needed between postdocs and those in the private sectors:

Differences by type of position can be readily inferred from the previous figures. Postdocs were far more likely than PhDs in the private sector to regularly do basic research and utilize advanced physics principles regularly in their work. A large proportion of PhDs in the private sector were regularly involved in design and development, applied research, and quality control.

These differences reflect inherent differences in these types of employment; postdocs are temporary positions with research agendas largely motivated by scientific exploration, while jobs in the private sector typically involve producing a tangible product for a customer or providing a service to a client.

A lot of data also on the job satisfaction, and whether they had sufficient mentoring from their advisors.

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Review of "Nuclear Forces: The Making of the Physicist Hans Bethe"

Here's another name that is a giant among physicists, yet it isn't a household name for the general public. This is a book review of of a recent biography of Hans Bethe published in this month's issue of Physics Today.

Of course, my admiration for Bethe can be summed up in this paragraph of the review:

Among the most pervasive features of Bethe’s emerging style was his fundamental criterion that theory must be grounded in real-world observation—a view he shared with other young physicists in his circle, including Edward Teller, Rudolf Peierls, Nevill Mott, Enrico Fermi, and later Richard Feynman. Bethe’s physics would not be aimed at formulating radically new ideas, but rather at critically analyzing and extending theories and formulating models that could test their validity.

This is probably a good book to read about Bethe. I plan on getting it, but if you have read it, I'd like to hear your views on it.

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The Man Who Put His Head In A Particle Accelerator And Survived

OK, it is highly recommended that one doesn't try this. But it is still an amusing story.




Of course, if this were to happen today, in the US, there's a good chance that several major safety violations would have occurred and this facility would have been shut down.

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What Is An Electron?

OK, I am normally a fan of videos produced out of JLab (check the series of educational and hiliarious FrostBite theater videos). Unfortunately, this is a rather surprisingly weak production coming out of this lab, explaining what an electron is:




OK, a "tauon"? Is this really the common name that is used in place of the tau? The Standard Model chart that we distribute to people, and also the particle data book, both call this a "tau". I know we are arguing about something as trivial as the name here, but really, if there's no reason to call the same thing with different names, then we shouldn't!

But the bigger problem is this. He said "electrons are so small, we haven't been able to measure it.."!!! This is extremely misleading and possibly erroneous. We HAVE been able to measure it! That's how we know it has a charge, a spin, etc.. etc. What we haven't been able to measure, and what I think he meant, was that we haven't been able to measure its SIZE!

This is important because I can easily see getting someone coming into a physics forum, showing me this video and quoting this particular line as "evidence" that we haven't been able to measure an electron! Again, it is extremely crucial that, when we communicate to the public who has a weak understanding of science/physics, we pay extra attention to not only what we say, but how we say it. There are plenty of times where what we mean is not what they understood! This video contained way too many things stated almost in glib, and that's too bad considering the opportunity they had to inform and educate. It was as if this was done as an after thought.

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Planned Apple Building Costs Several Times More Than NSLS II

I some time shake my head at some of the twisted priorities we often have, and how little we value science, which is the seed for many of the future economic growth.

I was reading a report on the future headquarters for Apple that have been dubbed as the Apple "Spaceship". Maybe it looks like a spaceship to the general public (or reporters), but to me, it looks like a synchrotron center! :) But what caught my eye was the current projection of the cost to be at $5 billion. Now mind you, this is an OFFICE COMPLEX, costing $5 billion!

Since it looked like a synchrotron light source, I decided to look up ballpark costs of a synchrotron source being built right now, and I know of one - the NSLS II that has just been constructed at Brookhaven. I suppose I could scout around more carefully at what it cost to build this, but I found an early estimate for it, and it costs around $1 billion. Now, this is not just the building, but also includes all the "content", which is the accelerator complex, the storage ring, etc.. etc. Anyone who has deal in purchasing scientific equipment can attest that these components are not cheap, especially when they are custom made.

Now, obviously, I haven't compared the floor space and size of these two buildings, but c'mon! An office complex costing almost 5 times the cost of a complex, complicated, and an extremely important scientific facility? What do they have? Solid gold toilets? Or maybe they are secretly housing a particle collider in there to challenge the LHC! Coming to your nearest Apple Stores: the iCollider!

For $5 billion, we can do a lot of things in science that will produce immeasurable benefits and advancements. But until society realizes the value and how they have benefited from such investments, and until people who have rather short attention space realizes just how far in advance they have to invest into science to reap its benefits, this upside-down skewered priorities will never correct itself.

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The True Science of Parallel Universes

For this one, MinutePhysics tackles the different models of "parallel universes". It took them more than a minute to do this, though... close to 5 minutes! :)

It boils down to 5 minutes of describing something that "has no experimental support" certificate! :)




Remember, kids. Physics is science, not philosophy! :)

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AMS Confirms Excess Positrons

Hope you guys were following the announcement today.

In any case, APS has released the paper on the latest result from AMS, reporting and confirming earlier reports on the excess positrons measurement. You can get acess to the PRL paper for free from the link. What does this all mean?

There has been no shortage of speculation about what might cause the positron “excess” above 10GeV. One idea is that relatively nearby cosmic bodies, such as pulsars, act as accelerators and colliders that produce antimatter, much like our terrestrial Large Hadron Collider. But a more exciting possibility is that the positrons come from the annihilation of dark matter particles, which may populate the Milky Way and its halo. Dark matter is, after all, a dominant form of the matter-energy budget of the Universe, but we don’t know its particle nature or how it interacts with itself and with normal matter (other than through gravitational interactions). It is no overstatement to say that identifying the dark matter is one of the greatest problems in modern science.

A lot of work remains to be done, but unlike the search for Supersymmetric particles, there are experimental indications that are consistent with Dark Matter models.

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Recent Results From The AMS Experiment

I don't know if the buzz surrounding this announcement will amount to anything, but there is certainly a buzz.

Samuel Ting will present the latest result from the Alpha Magnetic Spectrometer instrument that's orbiting earth. If you recall, the AMS went up with the Space Shuttle on one of its last missions. This could have some implications on the search for Dark Matter.

I probably won't have a chance to view the life feed. If you are planning on it, or if you have the chance to actually attend this event, I'd appreciate a brief report.

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Lifting Lemon

This is a simple experiment, and variations of this have been done in many classroom demonstrations, I'm sure. But it still becomes a topic of discussion as to why it happens, as demonstrated by the discussion on this video's YouTube page.



This link provides an explanation for this effect.

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Angry Birds At The Kennedy Space Center

You know it was bound to happen. When Angry Birds went into space, all the signs pointed to it partnering with NASA to come up with some educational tie-in. So now it has happened.

At NASA's invitation, the online game birds are roosting at Kennedy Space Center for the next 1 1/2 years in an effort to lure youngsters to the cosmic wonders of math and science.

The huge interactive exhibit opened March 22 and immediately packed in the kids, including this reporter's 7-year-old son, who couldn't get enough of the mirrored maze and design-your-own Angry Bird and play-the-game stations.

Too bad they didn't have this when I was there last December. Maybe I'll make it back there some time soon before the exhibit goes away.

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RToBad

Too eTooad 

Tooor

e here: http://www.star-telegram.com/2013/03/27/4733211/space-centers-angry-birds-exhibit.html#storylink=cpy

Philosophy Of the Higgs

A rather fascinating article that throws itself into the debate between physics and philosophy.

You can read the rest of the article for yourself. However, it seems that we can boil it down to the last two p paragraph in the article.

So then, should we physicists listen to philosophers?

An emphatic "No!", if philosophers want to impose their preconceptions of how science should be done. I do not subscribe to Feyerabend's provocative claim that "anything goes" in science, but I believe that many things go, and certainly many things should be tried.

But then, "Yes!", we should listen, as philosophy can provide a critical assessment of our methods, in particular if we consider physics to be more than predicting numbers and collecting data, but rather an attempt to understand and explain the world. And even if philosophy might be of no direct help to science, it may be of help to scientists through its educational role, and sharpen our awareness of conceptional problems in our research. 

I have no issues if I have to live with that. What it is saying is that philosophy doesn't really have any contribution on the physics itself. However, it may have some usefulness in the PRACTICE of physics, which isn't surprising because doing physics is a human endeavor.

However, there is still the nagging feeling that while physics can stand on its own to show how (i) it is useful and (ii) it has changed our perception of the world that we live in, the field of philosophy appears to be less able to stand on its own and depends very much on what comes out of science.

I think philosophy of science should not consider itself primarily as a service to science, but rather identify and answer questions within its own domain. I certainly would not be concerned if my own research went unnoticed by biologists, chemists, or philosophers, as long as it advances particle physics. On the other hand, as Morrison pointed out, science does generate its own philosophical problems, and philosophy may provide some kind of broader perspective for understanding those problems. 

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Solid State Higgs At The 2013 APS March Meeting

I mentioned the other day of the leg up that condensed matter physicists had on the high energy physicists in the hunt for Majorana fermions. The score so far is 3-0 in favor of condensed matter physicists.

It turns out that one can also argue that condensed matter physicists also beat their high energy physics counterpart in discovering the "Higgs"!

In 1981, Peter Littlewood and Chandra Varma, two solid-state theorists at Bell Laboratories in Murray Hill, New Jersey, realized that a mysterious effect seen in a niobium selenide superconductor could be explained by the jiggling of the invisible field that causes electrons in the material to pair up and move as one without resistance. Mathematically, the disturbance in the field looked very like one that is associated with the Higgs particle found by particle physicists.

This shouldn't really be a surprised, because as I've mentioned somewhere in this blog, and as stated in the article, the concept that arose to become the Higgs mechanism came right out of condensed matter:

It wouldn’t be the first time that particle physics stood on the shoulder of condensed-matter physics. When Peter Higgs, a theorist at the University of Edinburgh, UK, put together the idea known as the Higgs field in 1964, he built on a theory developed a year earlier, by theorist Phil Anderson, now at Princeton University in New Jersey, to describe the interactions of superconducting electrons. Higgs took the idea further, interpreting the field as a medium in empty space that would pull on particles, giving them mass. The Higgs bosons that made up the field would be invisible unless the field was jiggled in the right way, as occurs in high-energy collisions at the LHC.

That session on solid state Higgs at the APS Meeting sounded like a hoot. Seems like a lot of people are claiming Higgs-like scenario in their systems. Anyone attended that and can add a report or two?

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2013 US Spending Bill

The US legislators have finally finished some form of a spending bill for FY 2013 (several months late, if anyone is counting). Science Insider has a summary of how each of the science funding agencies within the US government fared with such severe budget cuts. It certainly looks like DOE's Office of Science suffered quite a blow.

The US is enjoying the fruits of its investment in science from way back in the 60s and 70s. The effect of a continuing downward trend in support for basic science since the 80s will be felt in the next 10 years. When historians 50 to 100 years from now look back and try to figure out when was the turning point that started the fall of the great US civilization, this will be a huge marker.

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Antiproton's Magnetic Moment Upholds CPT Symmetry

An amazing new measurement of the antiproton's magnetic moment by the ATRAP collaboration has improved the accuracy of the measurement its magnetic moment by 3 orders of magnitude. The new measurement agrees with the proton's magnetic moment to within the experimental error, thus still upholding the CPT symmetry.

The ATRAP Collaboration enters the fray with their own test for CPT violation. They look for a difference in the magnetic moments of the proton and antiproton. To enable this test, they precisely measure the magnetic moment of a single, trapped antiproton, achieving the most sensitive measurement to date of this quantity. They compare their result to the known value of the proton’s magnetic moment and find that the magnitudes are equal within experimental uncertainty, as predicted by the CPT theorem. 

The link above gives you free access to the paper.

Still haven't found anything yet that clearly violates the CPT symmetry.

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CPT

Sign of Annihilating Majorana Pairs

We now have more evidence of the presence of Majorana fermions in a condensed matter system.

I earlier pointed out 2 separate experimental evidence that are consistent with the existence of Majorana fermions in such systems. Now comes the 3rd evidence.

To help confirm recent observations, Aaron Finck and his colleagues at the University of Illinois at Urbana-Champaign have created a new system that uses a semiconducting indium arsenide nanowire hooked up to two superconducting leads. Theoretical models predict that two Majorana quasiparticles will appear at the two ends of the nanowire when a strong magnetic field is turned on. The team observed the presumed signature—a conductance peak in the wire at zero voltage. They also witnessed the splitting and re-forming of this peak as they varied the magnetic field and electron chemical potential. Although these peak modulations could arise from electron scattering effects, the authors show that their data are consistent with the wave functions of the two Majorana quasiparticles extending towards each other inside the nanowire, which leads to their transformation (or annihilation) into a more mundane collective state.

So now, in the race to find these Majorana particles, it's 3 for condensed matter, 0 for high energy physics.

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Alka-Seltzer Rocket

This is a fun demo. However, I'm not sure if this is suitable for very young kids. Someone could get his/her eyes poked! :)




And has been posted in the first comment, who the heck still has those photographic film canisters anymore? :)

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From Mars to the Multiverse

The 2012 Isaac Newton Medal lecture given by Martin Rees.




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Exoplanet Physics Project

Here's an interesting project aimed towards high-school level. This is IoP's Exoplanet Physics Project.




The synopsis says this:

The Exoplanet Physics Project is an extra-curricular science club designed to promote the practical uses of physics in society. They are available to Year 9 students from Partner Schools. Classes work in teams and are matched with an AS or A2 level physics Advisor from another school in England. Advisors are available to talk to students and support them throughout the project via an online blogging platform that is both easy to use and secure. You can register for the project or become an advisor on the Stimulating Physics website: http://www.stimulatingphysics.org/pupil-support-the-exoplanet-physics-project.htm

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What Are The Odds They Share The Same Name?

I'm sure many of you have come across the same thing.

Here in the US, the college football ranking and the choosing of teams to fight for the national championship is determined by something called the Bowl Championship Series (BCS). Of course, those of us in physics, and especially in Condensed Matter, already had a BCS name used since 1957 - the landmark Bardeen, Cooper, and Schrieffer paper on the theory of superconductivity.

Recently, I came across another name coincidence that is shared in popular culture. I watch HGTV channel quite often. In the many HGTV commercial promoting the channel and their various shows, they often play this tune, which eventually stuck in my head. I later found out that this is actually a song titled "Home" performed by a singer named Phillip Phillips, who won Season 11 of American Idol. Of course I didn't know that since I've never seen the TV show. But I thought it was a interesting coincidence because there's a well-known physicist in condensed matter (why is it always condensed matter?) at UIUC of the same name. In fact, there's a press release on a new paper that he and his co-authors had recently published on high-Tc superconductors (oh, it's that superconductivity connection once more!).

So what are the odds? After all, it really isn't a common name, or name combination. Have you come across the same thing where something in physics shares the same name with popular culture?

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Phonon Laser - Part 2

3 years ago, I highlighted a report on 2 papers advancing the concept of phonon/acoustic laser. This week, it looks like significant progress has been made.

Now, the paper of Mahboob et al. reports a significant step towards this goal. The authors create a purely mechanical system of three energy levels that is reminiscent of a three-level laser scheme (see Fig. 1, top panel). In a three-level laser, atoms are excited by an optical pump (usually another laser or a flashlamp) from the ground level (1) to a higher energy level (3), and then quickly relax through spontaneous emission and accumulate in the upper laser level (2). If the population of level 2 exceeds that of level 1 (a condition known as population inversion), photons resonant with the 1→2 laser transition get amplified through stimulated emission: the medium acts as an optical amplifier and, when placed within a cavity, lasing occurs if the gain exceeds the losses.

The link given above gives you access to the actual paper, so don't miss it.

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Old Videos Of Ernest Lawrence?

This is annoying. Berkeley Lab released a bunch of old footage, but the videos have no accompanying explanations. They just dumped them out on YouTube and left it at that!

Anyway, from what I could gather, all the videos involved Ernest Lawrence. They start from his demo of the cyclotron, all the way to his acceptance of the Nobel Prize.













It's a shame that such historically significant footage were not accompanied by detailed descriptions.

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Feynman's Double Slit Experiment

Either I'm psychic or I have excellent timing in these things.

I showed an illustration of the double slit experiment just a couple of days ago using both single photons and single electrons. Well guess what? Physics World today highlights a modern version of the double-slit experiment using electrons, and supposedly, this one is the closest to Feynman's original thought experiment.

The electrons were created at a tungsten filament and accelerated across 600 V and collimated into a beam. After passing through the double slit, they were detected using a multichannel plate.

The intensity of the electron source was set so low that only about one electron per second was detected – which ensured that only one electron at a time would ever pass through the slits. At this rate it took about two hours for a pattern to build up on the detector – a process that was recorded in real time (see video below). Measurements were repeated with the mask in a series of positions: first blocking both slits, then one slit, then none and then the opposite slit. As expected, the double-slit pattern was seen when the electrons had access to both slits, but not seen when one slit was blocked.

The link shows a video of the accumulation of the signal. You also get free access to the paper since this is a New Journal of Physics article.

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Topological Insulators Found In Nature

Looks like Mother Nature knows how to cook these things way before many of us know about it.

Newly-found samples of kawazulite found in gold mines in the Czech Republic shows properties of being a topological insulator, and may in fact have a higher quality than made-made ones.

In search of materials that display these properties, Gehring and his colleagues examined a natural sample of kawazulite, which contains bismuth, tellurium, selenium and sulphur, found at a former gold mine in the Czech Republic. Lab-made samples of kawazulite have already been shown to be topological insulators, but no one had checked for the property in natural samples.

The team cleaved off single crystalline sheets 0.7 millimetres wide and applied the standard test for a topological insulator: photoelectron spectroscopy. This involves measuring the properties of electrons dislodged when ultraviolet light is fired at a material’s surface. Their results confirm that the electrons’ energy and momentum distribution matches predictions for a topological insulator.

Feng Liu, a materials scientist at the University of Utah in Salt Lake City, notes that the team’s natural sample contains fewer structural defects than its lab-made counterparts, reducing unwanted conduction in the bulk. “It may turn out to be cheaper to use a natural supply of topological insulators,” says Liu.

Obviously, these material are not in such high demand right now. But wait till something useful can be made out of these things.

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What's The Difference?

OK, I have two figures here for you:

A.

B.

Other than the orientation and the pixel density, can you tell what is what in these two, and what are the differences?

No?

What if I tell you that one is a 2-slit interference experiment using single electrons, while the other is a 2-slit interference experiment using single photons. Can you tell which is which?

You are not at fault if you can't, because I won't be able to either, just from looking at the figures. Figure A is the single-photon interference experiment, while Figure B is the single-electron interference experiment (G. Matteucci et al., Eur. J. Phys. v.34, p.511 (2013)). The effects look the same for both.

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Observing Matter-Antimatter Oscillations

This result out of LHCb on the B-meson matter-antimatter oscillation has been getting a little bit of publicity lately (see the PhysicsWorld coverage). The paper has now appeared on PRL, and you can get a free copy of the paper at the APS Physics link.

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"Admissions Criteria and Diversity in Graduate School"

I only managed to read through this article yesterday, so this is a bit late for something that has appeared for a while.

This is a rather interesting article that first appeared in the APS News. It examines that effect of using a GRE cutoff score as a basis for graduate admission in physics, and how this may contribute to a reduced diversity for American students.

Justifying using the GRE becomes significantly more complicated, however, when the test results are dissected by race and gender. The figure plots QGRE scores by race/ethnicity and gender for US citizens whose intended graduate major was "physical sciences". The top and bottom of the lines are the 75th and 25th percentiles of the score distributions, respectively; the tick is the mean. This pattern is qualitatively unchanged when controlling for undergraduate GPA. Note the implications for diversity of using 700 as a minimum acceptable score: nearly three quarters of Hispanics would be rejected, and significantly more than this for American Indians, African Americans, and Puerto Ricans; similarly, women are filtered out at a higher rate than men. Mixing cut-off scores with these racial and gender disparities sets the foundation of a glass ceiling erected by the lopsided treatment of minorities and women before they even set foot in grad school. 

The author certainly presented some compelling statistics on why the GRE cutoff rule not only does not provide a good prediction on a student's performance in a graduate program, but also contributes to racial and gender disparities in admission.

And this brings me to another, slightly different item of discussion. The article looks at the diversity among the US students in physics. Many of us who went through the STEM educational program often see not only US students, but a large population of international students in these programs. In fact, in many schools, especially smaller ones, the number of international students can outnumber US students. This is definitely true in physics and engineering. There is a large population of international students from China, India, Korea, South America, etc.. So while there may not be as much "diversity" in the US student population in STEM fields, I find that there is a huge degree of diversity for the overall student population in these fields of study, more so then students in the liberal arts, economics, law, etc. Did you take an elective course in literature, art history, philosophy, etc.? How diverse in terms of racial/national origin were the students? How about those majoring in those fields?

Students in STEM areas have a larger opportunity to interact and experience students from other cultures and nationalities over a longer period of time. Often, they go through the degree program together. They tend to be more familiar in dealing with people from a wide variety of background. And you know what? If they continue work in such fields, the diversity carries over. Attend any physics or engineering conference, and you'll find a huge and significant international participation.

This diversity in STEM areas is often overlooked and is seldom considered as a strength in the development of students going through the program.

Zz.

Physics And Your Food Blender

I've mentioned several times on here on the effort to clearly demonstrate how physics is at work in the world of gastronomy. This is not entirely there, but certainly related to it. It is a Wired article on how the blender works, including a video that demonstrate what happens during its operation.

Question is, will it help me to make a better margarita? :)

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Measurement Of The Neutrino Oscillation Angle Theta13

This is a very good review article on neutrino oscillation and also the measurement of Theta13, which has been a very active investigation area lately. The article is aimed at "non-HEP Physicists", meaning you have to remember quite a bit of your quantum mechanics to decipher all those matrices. You get to see, quite early on, why the detection of the change in flavor of neutrinos allows not only the measurement of the mixing angle, but also implies that neutrinos must have mass.

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High-Energy Physics Is Still a Worthwhile Investment

Not sure if there's a contagious disease going on, or if something is up somewhere, but we now have two different articles written about the worthwhile investment in High Energy Physics, within the span of a couple of days.

Granted, the earlier one was done by an "amateur" for a school newspaper. This latest version appeared in The Atlantic and written by a physicist.

Wilson could have made a case for investments in high-energy physics transferring directly to national security. And in the decades since 1969, they have. Detectors developed in searches for dark matter, believed to make up 23 percent of the content of the universe, could notice a dirty bomb crossing our borders. Beams of particles can scan cargo containers without opening them, or even scan people and their luggage at airports, as is now commonplace all over the world. Beyond security and shrink wrap, we have also seen advances in medicine, computing, and data mining. According to the U.S. Department of Energy, tens of millions of patients receive accelerator-based diagnosis or therapy each year.

In the decades since 1970, high-energy physics has made stunning progress in the archeology of the early moments of the Big Bang. In the same timeframe the fraction of the U.S. gross domestic product dedicated to research in the physical sciences has been cut in half. We are currently in a situation where the next machine, either taking us to higher energy or allowing us to probe this potential Higgs boson in greater detail, might be out of reach of our finances and political will.

It certainly is true that high energy physics gave birth to the field of accelerators. However, as it is now, the field of accelerator physics certainly has been clearly separated from high energy physics. In fact, the overwhelming number of accelerators in this world have nothing to do with high energy physics. Still, the need for cheaper, more efficient future particle colliders at higher energies will continue to drive innovations in accelerator physics that will translate into better accelerators for other applications.

Zz.

The Devastating Mathematics Of Budget Cuts In The US

The failure of the US politicians to come up with a budget to prevent the current sequestration is devastating to science research and funding. There is an almost universal agreement on this. However, the way it is done is even more devastating that many people realize, and I often wonder if the politicians that are doing this realize this as well. I'm tempted to think that some of them do not realize this, because this is done often enough, year-after-year, that they don't seem to understand the severity of what they are doing.

Here are some simple mathematics that anyone can understand, and it illustrates the utter stupidity of what they are doing.

Let's say that Govt. Agency X has a budget of x. This is the amount of money that they are given for the fiscal year (12 months). So on average, this agency has x/12 amount of money to spend per month, which is 0.083x per month.

Budget = x
Spending per month = x/12 = 0.083x

OK so far?

Now, since Congress can't get their act together and come up with a budget when they are supposed to by the end of September, they pass this thing called "Continuing Resolution". This is where, devoid of a budget for the new fiscal year, they continue working using the budget of the previous year until a new budget is agreed upon. So this agency will continue to work under the assumption that it has x amount of money in a fiscal year! In other words, the agency will continue to spend, on average, 0.083x per month.

Average spending per month for new fiscal year = 0.083x

Now, let's say, at the end of February of the following year (i.e. 5 months into the new fiscal year), a new budget is agreed upon and takes effect. This means that Agency X has spent:

Amount of money spent = 0.083x * 5 months =  0.417x. ----- (1)

So this agency has spend 0.417x amount of money already by the end of February.

Unfortunately for Agency X, its budget was cut by 12% (the same devastating amount being cut during this sequestration). What this means is that instead of getting x for the new fiscal year, the agency is supposed to get 0.88x.

Budget for new fiscal year = 0.88x
Average spending per month = 0.88x/12 = 0.073x

By the beginning of March (after 5 months into the new fiscal year), this agency should have 0.513x amount of money left, i.e.

0.88x - (5 * 0.073x) = 0.515x

But that is not what is going on. Because of the continuing resolution, the agency was spending, on average, 0.083x per month, for 5 months, for a total of 0.417x (see (1)). The amount of money left for this agency is:

Amount of money left = 0.88x - 0.417x = 0.463x. !!!!!!!!!!!!!!!!!

This is significantly different and LOWER than 0.515x amount of money had the budget cut been applied AT THE START OF THE FISCAL YEAR. This agency is in a deeper financial trouble by this time because it has even less money than expected.

There are two devastating impact here:

1. The budget for this agency was cut from x to 0.88x. That in itself creates major problem

2. However, it was made WORST when congress could not come up with a budget when it should and instead, applied a continuing resolution for several month before indicating that this agency will get a budget cut.

The agency would have been better off to receive a budget of 0.88x at the start of the fiscal year. It knows what it has to spend. Instead, not knowing and having to spend using the old budget only causes it to spend on money that it won't have. The longer the continuing resolution goes on, the more devastating the cut will be.

This is what is going on right now in the US budget. We were under a continuing resolution since the start of Oct. of 2012. The 12% budget cut due to the sequestration is devastating because the money that's left is significantly smaller than had the 12% cut been applied at the beginning of the fiscal year. The budget cut is bad enough. The inability of Congress to come up with a budget ON TIME, WHEN IT SHOULD, creates a double-whammy.

In case you think what is happening this year is unique, think again. I do not remember the last time the US Congress managed to come up with a budget on time, when it should. The continuing resolution legislation has been invoked almost every single year lately, it seems. When this happens, any branch of the Govt. that ends up receiving a budget cut often has to deal with massive problems in trying to balance out what needs to be done and what has to go.

We ask our elected officials in Washington to do two major tasks: (i) come up with sensible legislation and (ii) come up with a federal budget. One can argue about how successful they are with (i), but for (ii) they have done an extremely poor job as far as the timeliness of what they should accomplish. For most of us, we get penalized for not completing something on time, when we're supposed to. Obviously, this doesn't apply to those who come up with our Federal budget.

Zz.

Catch And Release Of Photons

I'm always amazed by the nature of these experiments, and continue to be awed by what have been accomplished.

Two different groups published two different papers in this week's PRL, all reporting on the ability to store photons and then releasing them. What is even fascinating is that each group used different schemes to accomplish the same thing. I already reported on one of these results earlier. So check out the first link for a review of these two experiments, and you also get a link to free access to both papers.

Zz.

Chasing The Higgs

Quick, read it before the free, open access goes away!

The NY Times has a lengthy article on the hunt for the Higgs (yeah, yeah, I know. Another one!). Still, it is nice that a prominent newspaper is still covering something like this.

As you read it, take note of the cast of characters in the story. If you are not familiar with the type of collaboration in one of these large science projects, note that many of the people who are associated with CERN or the LHC or the hunt for the Higgs are NOT CERN employees! Many, if not most, of them are employed by other institutions. They just happen to do their job AT CERN or AT the LHC.

I mention this because I've been asked by so many kids who want to work for LHC, or who wants to work for NASA etc. They think that the only way to be involved in these things is to be employed by those organizations, when nothing can be further from the truth. Many of these projects are run, administered, etc., by people from other organizations. Here in the US, people who work at many of the large facilities at various US National Labs are NOT necessarily employees of those laboratories. Large user facilities such as the NSLS, APS, SNS, LCLS, etc. often attract scientists and engineers from other institutions to perform their work/investigation at these facilities. Even the Tevatron, when it was operational, had huge number of physicists from other places, very much like the way CERN/LHC is right now.

So kids, don't aim your ambition to work for a particular employer or location. Aim for the type of profession that would be able to perform the task that is involved in working at that location.

Zz.

Particle Physics Is Worth Funding

I wasn't going to comment on this article, but I decided to anyway.

This appears to be an opinion piece for a college newspaper at Oklahoma University. It has some minor issues that do not detract from the central message of the article. The author is presenting a case on why something as esoteric as particle physics is worth funding.

Sounds interesting, but laypersons are not amateur physicists, and want to know the practical benefits of what their dollars are funding.

The difficulty with this reasoning is it ignores how the nature of science operates. Albert Einstein did not anticipate his theories of relativity would play a prominent role in GPS satellites and smartphones. The discovery of quantum mechanics, perhaps the most esoteric of the sciences, would ultimately give rise to conductors and computers. Virtually all of electricity can be traced to research conducted in the 19th century that was thought to have little, if any, practical benefit. Many of the machines found in hospitals such as MRI’s are based upon principles of physics discovered by physicists who had no interest in medicine. In order to properly do science, even the most abstract subjects need and deserve funding.

This certainly is true, and a message that I've posted here many times.

The minor issues I have with this article are:

(i) the technical aspects of it, especially when he said" ... The discovery of quantum mechanics, perhaps the most esoteric of the sciences, would ultimately give rise to conductors and computers..." when I think he meant "semiconductors". The discovery of QM did not give rise to conductors, because we already know about Ohm's law and everything else about conductors well before QM was formulated. We even know about semiconductors before then. We just don't know the physics of semiconductors.

(ii) the "references" being used are often other news articles. This is fine IF you are commenting on that news article (like what I often do in this blog). But if one wants to have proper citation to back one's claim of either science or a fact, using a news article is equivalent to passing on a piece of gossip. We have seen how news articles can often skewer something, or even get it totally wrong. So not a good idea to depend on such sources to justify one's opinion.

There's also something interesting here. The article is written by a philosophy major. On one hand, it is too bad someone with a physics background (a physics major) did not write this. I mean, who else is more qualified to try and sell to the public why they would fund what they do? I'm guessing such a person would not commit the two issues I listed above. But on the other hand, having someone else trumpets the importance of what we do, someone without a direct financial, vested interest, might carry more weight. Having a non-physicist urging for support for particle physics might certainly be a novel effort that might get more attention. I don't know.

The article missed a few other important reasons why particle physics is worth funding. I mentioned one important aspect of it earlier where particle/high energy physics experiments drives innovation and technological advancement in the area of detectors. Again, it is worth repeating that while most other areas of science construct and design their experiments based on equipment that they can buy commercially or that are available on hand, high energy physics often can't do that. This is because many of the detection and things they want to do, and the accuracy/resolution/speed that they need, have not been invented. So what they end up doing is to innovate and invent their own devices and detectors. This innovation and technological advancements eventually trickle down to other areas of physics, science, and the general population. And this area of detectors is just one example. One only needs to look at their computing needs and how much data they have to handle to know that they are also doing unbelievable innovation in terms of data transfer, handling, computing needs, etc. Don't tell me other companies are not observing and learning from this very carefully.

And speaking of detectors, if you wish to further check up on my claim of particle physics innovation in this area, check out the proceeding from the 2nd International Conference on Technology and Instrumentation in Particle Physics (TIPP 2011). Papers are available for free. Bookmark it. I can guarantee you that a few of these that were designed for particle physics experiments will directly impact our lives in the next decade when they are used in other instruments.

Unfortunately, here in the US, funding for high energy physics continue to decline. The impact on this to the US intellectual activities, innovation, and economy can only felt once it becomes too late.

Zz.