A Laser-Based Table-Top Neutron Source? I'll Take One!

Exciting news for those who depend on neutron sources for to study things. A new development in using high-powered laser to produce energetic neutrons with reasonable flux has been reported.

Neutrons are a valuable tool for scientists in many fields, allowing them to probe the structure and dynamics of a range of materials. Today, the main drawback of neutron science is that intense beams of neutrons must be produced in either nuclear reactors or dedicated accelerator facilities – making a laser-based table-top source very attractive.

This scheme has now been put into practice by Markus Roth of the Technische Universität Darmstadt and colleagues at Los Alamos and Sandia National Laboratories. Roth's team directed extremely powerful and well defined pulses from the Los Alamos TRIDENT laser onto a 400-nm-thick plastic target doped with deuterium atoms. This was positioned just 5 mm in front of a secondary target made from beryllium.

Even though the pulses delivered less than a quarter of the energy employed in previous experiments, they produced neutrons that were nearly 10 times as energetic – up to 150 MeV – and also nearly 10 times as numerous. In addition, many of these neutrons were emitted in the forward direction, which the researchers attribute to one specific kind of nuclear reaction, the break-up of deuterons.

This has the potential to either replace, or supplement spallation neutron sources. There's still a lot of work to be done, but it looks like this could make having neutron source for material study as easily has having x-ray sources for such a study. Of course, we haven't considered the safety issues here since neutrons are significantly more dangerous to deal with here.

Zz.

RHIC In Danger Of Being Shut Down

In operation for only about 12 years, the Relativistic Heavy Ion Collider at Brookhaven is in danger of being shut down, due to budget shortall for DOE's Nuclear Physics division.

A panel of scientists has recommended shutting the last U.S. grand atom smasher, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in Upton, New York, to make room in a tight budget for other projects funded by the Department of Energy (DOE).

Closing RHIC would be a disaster for the U.S. nuclear physics community, says Robert Tribble, a nuclear physicist at Texas A&M University, College Station, who chaired the committee that suggested doing exactly that in a report today to DOE's Nuclear Science Advisory Committee (NSAC). "I don't think there are winners and losers here," he says. "We're all losers if this comes to pass." NSAC is expected to approve the report tomorrow, and DOE has usually followed such recommendations from its advisory panels. 

While this is a sad news, it is not unexpected, considering what the panel had to deal with, especially when faced with the 2 new construction projects that they had to consider.

The Tribble committee weighed the relative importance of three very different facilities. RHIC uses twin accelerators to smash heavy nuclei together to produce fleeting puffs of a weird type of matter called a quark gluon plasma that filled the newborn universe. In contrast, DOE's other existing major nuclear physics rig, the Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, fires electrons into protons and neutrons to study their inner workings. In addition, physicists plan to build a $615 million Facility for Rare Isotope Beams (FRIB) at Michigan State University in East Lansing that would generate myriad exotic nuclei usually produced only in supernova explosion.

Researchers are currently finishing a $310 million upgrade to CEBAF, and the committee recommended exploiting that investment, Tribble told NSAC. That forced the group to choose between continuing to run RHIC, which has been collecting data since 2000, and building FRIB, which could start taking data by the end of the decade. The committee included representatives from all three projects, says Tribble, who declined to give the vote tally.

As has been said, we are all losers if this facility shuts down.

Zz.

Quantum Biology

I had mentioned already on the emerging connection between quantum mechanics and some aspects of biological phenomena (see here, here, and here). This BBC science article reviews the current effort to use quantum mechanics to explain some of the biological effects.

The most established of the three is photosynthesis - the staggeringly efficient process by which plants and some bacteria build the molecules they need, using energy from sunlight. It seems to use what is called "superposition" - being seemingly in more than one place at one time.

Watch the process closely enough and it appears there are little packets of energy simultaneously "trying" all of the possible paths to get where they need to go, and then settling on the most efficient.

You may read the other examples that they gave in that article. But what irked me slightly is what was mentioned near the beginning of the article.

Disappearing in one place and reappearing in another. Being in two places at once. Communicating information seemingly faster than the speed of light

This kind of weird behaviour is commonplace in dark, still laboratories studying the branch of physics called quantum mechanics, but what might it have to do with fresh flowers, migrating birds, and the smell of rotten eggs?
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Until recently, the delicate states of matter predicted by quantum mechanics have only been accessed with the most careful experiments: isolated particles at blisteringly low temperatures or pressures approaching that of deep space. 

That is utterly false, because our modern electronics are the proof to counter that. QM isn't restricted to such esoteric conditions. QM is what is responsible for our iPhones, iPads, computers, MRI, electron microscopes, flat-panel TVs, PET scans, etc... etc. Sure, to be able to observe the "weird" behavior of QM, we will have to go to extremely difficult conditions, but the description of QM are directly used for many everyday items and process. After all, this is what the biologist here are trying to do as well, use the description of QM to explain observed, macroscopic biological phenomena.

BBC News science section needs to get rid of this myth quickly. It undermines the usefulness of QM.

Zz.

Update On the Mansuripur "Paradox"

I had mentioned the rebuttals that this "paradox" has been getting ever since it appeared. Science has an updated review on the status of this thing and has essentially declared it solved.

Mansuripur is sticking to his guns. He argues that hidden momentum, which was identified in the 1960s, is an ill-defined concept that merely papers over the problem. "That's always been the problem with hidden momentum," Mansuripur says. "You know that something is missing, so you just postulate its existence." He says his approach eliminates the need for hidden momentum.

Others say that hidden momentum is part and parcel of relativity. "If you have a system with internal motion that is subject to an external force, then hidden momentum is a general property," says Daniel Vanzella, a commenter at the University of São Paulo in São Carlos, Brazil. "It's not an ad hoc invention put in to reconcile things." Vanzella also notes that mathematically, the Lorentz force law can be written in a form that guarantees it will jibe with relativity, so it's "simply impossible" for it to contradict the theory.

There was a question towards the end of this article on whether this should have been published or not. I see no problem in it getting published (although, I don't think it should have been in PRL). Mansuripur clearly found something intriguing that needed to be sorted out. It was not done out of deceit and it was definitely a legitimate question. The rest of the community then responded in kind to correct what they see missing or in error. That's what this whole publication process is supposed to do, and this is how it should work. Publication never guarantees validity.

Zz.

We Don't Need No Stinking Theory Of Everything!

This is a Q&A with Lisa Randall.

The reason why I'm highlighting this is that the questions being asked is the type of questions many of us faced with we talk to the public. The very first question, for example, is rather typical:

Doesn't every physicist dream of one neat theory of everything?

Of course not! But the public has a very narrow idea of what physics is. Many are surprised when I tell them that the largest percentage of physicists in the US are working in the area of condensed matter/material science, which is not the first of study that directly involves the Higgs, high energy physics, string, etc. So for many of us, this "theory of everything" isn't something we dwell on that much, not to mention, there are even prominent physicists who think that this "theory of everything" is a myth.

In any case, this article covers some of the common questions that we often see.

Zz.

Immovable Object vs. Unstoppable Force

As stated in the video, I too have seen such a question being asked on the internet numerous times. And as can be seen in the video also, question like this is often asked without clearly think of what the question actually means. This is important in physics because the question that we ask can sometime be as important as the answer that we get. So having a clearly defined question is crucial.



Zz.

"I Want To Ride My Bicycle, I Want To Ride My Bike...."

Bicycle! Bicycle!

Yes, we are doing bicycle physics! I already mentioned about this quite a while back. But there's new coverage on this not-as-simple-as-you-think phenomenon of riding a bicycle. The new coverage doesn't present anything new, though, but merely reemphasize the fact that 'steering' is an important factor in how one can balance on 2 wheels on a moving bicycle.

Partially through this research, physicists have come up with an explanation for why bicycles don’t tip over: they always turn toward the direction they’re falling. When the bicycle begins to tilt to one side, the front wheel turns in that same direction, which prevents the bike from falling over. This can be verified by locking the handlebars so that the bicycle can’t turn. When you do this and give the bike a push, it topples over.

Now, the reason why the bicycle steers in the direction that it is about to topple over isn't as clear.

That’s where things get really complicated. Rather than a simple explanation, scientists have developed a formula that determines whether or not a bicycle design will have this essential attribute. Insomuch as it has been tested, the formula works. Unfortunately, it’s not a simple two- or three-variable equation: it requires 25 different characteristics of the bicycle to make a prediction.

So do we know how a bicycle works? Technically, yes. We have an equation that can predict whether or not a particular design will be easy to balance. But that doesn’t mean we fully understand what’s going on and the one-sentence explanation of what keeps it upright only leads to more questions that aren’t so easily answered.

So there! Even the everything, common thing that we all are familiar with can still be puzzling.

Zz.

Dance The Higgs

Ah, another one of those!

I made no bones about my feeling on such things. This appears to be another attempt at incorporating physics into the arts. In particular, they're incorporating the apparent discovery of the Higgs into dance and photography.

Our Reintegrate project will translate the details of the Higgs boson discovery into a series of precisely choreographed visual images. By translating potentially the greatest breakthrough in particle physics in the 21st century through the intersecting artistic mediums of photography and dance, we will investigate the problem and benefits of communication across three disciplines that weigh heavily toward the non-verbal articulation of ideas.

 First of all, I don't quite understand exactly what is meant by the phrase that I've bold in that paragraph. Secondly, since we're "talking" about non-verbal articulation of ideas here, I would like to challenge the organizers to try this experiment: DO NOT tell your audience in advance what the dance is about. Don't even give them a title (thus, the non-verbal part). Just present the dance. After the presentation, do a poll and see what they think the dance is about. What are the chances that they actually will say "Oh, it is about the problem and benefits of communication across physics, dance, and photography on the discovery of the Higgs boson"?

Now, you could ask me "But ZapperZ, arts, such as dance, is very subjective and interpretive. You don't expect them to actually come up with not only an accurate answer, but also one consistent answer, do you?" And I would say, that's my whole point! If you want to communicate about the discovery of the Higgs, the importance of the physics of the Higgs, etc., your BEST BET in doing that is to convey an UNAMBIGUOUS message is via direct, verbal communication! It cannot be done effectively and unambiguously via "dance". I just don't see it.

If you want to do this simply for entertainment, fine. Knock yourself out. But I seriously question when this thing is being "intellectualized" as if such an exercise can actually produce anything meaningful, informative, and accurate. This is just too close to being an Emperor's New Clothes to me. A lot of people are going along with the "intent" but there hasn't been a lot of substance.

Zz.

Physics Is Fun?

I've posted something on this topic before, and I'll continue to do it. I always like to highlight classes and/or teachers that go beyond what they have been asked to do and try to make a physics lesson more interesting and more engaging to the students. This is one such example.

Montgomery's physics class is certainly not what one would think of as a traditional classroom.

Yes, there are lectures. Yes, there is homework. But there's also a lot more that this group of seniors gets to experience.

"The fun thing about older kids, they're still kids," she said. "They just want to play."

I also like the observation that she had on her students.

The hands-on activities help students relate to what they are studying. But even that doesn't always make it easy.

"They still struggle. When you go to paper and pencil, it helps that they have that interest. But they have to apply the math," she said. "Physics is hard."

In the past, almost no one took physics at the high school level. Until the State of Ohio stepped in and gave it a boost.

"They made it so you have to have physics to get an honors diploma. Our numbers practically doubled after that," she said. "They might not be excited to take it, but they find something about it that is interesting to them."

Being that the class is generally made up of some of the brightest students in the senior class, Montgomery said the students don't always deal well with struggling to understand the difficult subject matter.

"They still think that because they're good at everything else, they expect to get every question right the first time," she said. "I still have to go back and look at questions more than once sometimes."

As we all had to do if we're in education.

Zz.

So I Am Your Intro Physics Instructor

{I wrote an essay on what I would say to my student if I were his/her academic advisor. Since this is the beginning of the semester for many schools (or the beginning of the school year in parts of the world), I thought it would be appropriate for me to "publish" another "speech". This time, I'm directing it to a class of  intro physics students.}


Dear Students,

Welcome to the intro physics course. For many of you, this is your first college level physics course that you are taking. Hopefully, it will lay the foundation for the rest of your undergraduate education and becomes something that you will find useful.

I would like to let you know of some of my expectations from you, and would like to let you know of what you can expect from me. I know that many of you are taking this course because you have to, not because you want to. I am also aware that the majority of you are not physics majors. However, I hope to impress upon you why you would want to do well in this class. Besides the fact that it will affect your overall GPA, I want to make you aware that there are a lot of things you can learn and acquire from this class that will be very useful to you not only in your academic pursuit, but also in other parts of your life later on.

The most important point I want to make is this: while the material that we will be covering is important for you to understand to do well in this class, what is equally important is the ability in analyzing a problem that you are faced with, and figuring out how to systematically solve it. I want you to pay attention not only to the content of the course, but also to how I approach a problem and how I go about solving it. I will try to teach you the physics and also the problem-solving technique. I will try, as best as I can, describe to you what I'm thinking when I look at a problem, and how I analyze it to know what to start with and how to proceed.

Keep in mind that while this is something that I can attempt to teach you, it really is a skill that you can only acquire after repeated practice. It is very much like learning how to ride a bike. I can tell you what to do, but you'll never gain the skill to ride a bike until you have practiced several times, and taken a tumble here and there. The homework that you will have to do is meant to be your vehicle to practice on to acquire such skill.

At some point, you may question why we are studying certain things, or why we are trying to tackle a certain type of problem. One example that I can bring up is the projectile motion that you will see and have to solve till you're sick of it. You may find it strange that we are asking you to solve various configurations of the projectile motion problem. Are we trying to train you to be an artillery person? No.

You see, I could teach you that F=ma and then walk away. There. We've covered a huge section of our semester already. Now, go use that to build me a house. Chances are, you can't. What you've received is only a superficial knowledge. You may know the relationship between F, m, and a, but you don't understand how it is used or how it can be applied. Knowing how to do that will give you knowledge beyond the superficial level. So we try to apply F=ma in a number of examples. Unfortunately, the examples that we can use that are simple enough are limited. We can't exactly apply all the real-life conditions to an example because it will them make the problem too complex, and you will be thoroughly confused. You will be distracted by the complexity and lose the focus on how F=ma is applied. So we have to deal with simplified examples on how we use F=ma, and this is where examples of projectile motion, motion of objects sliding on inclined planes, etc.. come in. We are not trying to turn in you experts in artillery or building a slide. You should not be focusing on the nature of the example. You should be focusing on the aim of these examples, i.e. how F=ma is applied.

Now, because I want you to understand both the material and the technique, you should not hesitate to ask me questions if you do not understand anything. This is especially true if you do not understand why, in solving a problem, I would do such-and-such, or how I know to start with such-and-such if it is not obvious to you. It is important that you make sure you understand things every step of the way, because we will be building on you learn early in the semester and apply it to more complex situations later on. If you start with a shaky foundation, you will not be able to master the material that you will be faced with later in the semester. So please, ask me questions in class, or come to my office hours. I have been paid to serve you and impart knowledge and skills. Make use of this opportunity.

My last advice to you here is that the process of learning is a very private, internal activity. While you have your texts, your notes, your instructor, etc. to help you, in the end, it is YOU who have to make the effort to acquire such knowledge and skills. It must sink in for you. At some point, you have to figure things out for yourself. It means that you need to understand things on your own, and be able to do your own thinking. You have to figure our how you understand things and what you need to do to get something.

And this is where this physics course can be of a tremendous value to you, not just for your future academic pursuit, but in your later life. To put it bluntly, you will consciously learn how to think and how to analyze a problem. You will learn to what degree you can say that A causes B, and how can you figure out what affects what. This ability transcends a physics class and will be extremely useful to you as you become a responsible citizen.

I hope you have a productive and enjoyable time in this class. Now let's get to work.

Zz.

"Quantum Information And Randomness"

If you haven't come across this yet, don't miss it. This is a very good review of what is essentially the most comment topic in Quantum Mechanics - randomness that is inherent in the standard interpretation of QM. The co-author of this article is Anton Zeilinger, so you are getting some of considerable authority on the subject. The review on the Bell-type experiments are excellent - pay attention to why this doesn't violate SR.

Zz.

"How many dominoes does one need to topple a domino as tall as the Domtoren?"

Supposedly, that was a question in a 2012 Dutch Science Quiz.

Anyone who has followed this blog for any considerable period of time would know that I love reading and studying about mundane phenomena and physics, and this one qualifies as one. PhysicsWorld is reporting a study appearing on ArXiv recently to answer that very question.

The Domtoren is a 112-m-tall cathedral tower in Utrecht and the idea is to begin with a standard-sized domino, which topples a larger domino. This then topples an even larger domino and so on until a Domtoren-sized domino can be felled. The process is called "domino multiplication" because a tiny tap on the first domino can, in principle, topple a huge monolith. Now, Van Leeuwen has calculated the upper limit on how much larger each successive domino can be. In principle, his calculations suggest that the maximum ratio of successive domino heights can be about 30% larger than the widely accepted value of 1.5. 

Of course, he had to make some simplification to his model:

But in the real world not all that energy is channelled into bringing down the next domino in line. First off, the dominoes bounce a little as they strike one another. Next, they have a tendency to slip along the surface they are stood on as they are nudged, lessening the chance of a fall or causing them to fall back towards the striking domino. And finally, once in contact, they drag against one another as they fall.

In his model, Van Leeuwen simplifies the situation by assuming that the collisions are completely inelastic, that the friction between the dominoes and the surface they stand on is infinite, and that the dominoes, once touching, experience zero friction and simply slide over one another. 

And of course, there's a video demo, but it isn't related to this particular preprint:



Fun!

Zz.

Misconception of the Heisenberg Uncertainty Principle - The Video

Back in 2006, I wrote an entry on the misconception of the Heisenberg Uncertainty Principle. I used light going through a single slit to illustrate what the HUP really is.

Now, I've found a video illustrating JUST THAT!



I hope that with the video, what I was trying to explain is even clearer than before.

Zz.

The "Brian Cox Effect" In The UK

I've heard about this from last year where the enrollment in physics degrees in the UK has seen a significant surge, but this one kinda reinforce it.

Manchester University is the first in the country to require students to gain two elite A* grades – alongside an A – at A-level to get onto its physics degrees.

It represents the highest entry threshold for any physics course in Britain, including those run by Oxford, Cambridge, Durham and Imperial College London. It is among only a handful of degrees in any subject nationally to demand two A*s.

Manchester has always been a popular choice for physics but the university admitted that a recent rise in applications had been partially driven by the attraction of Prof Cox, one of the department’s academics and presenter of television series such as Stargazing Live and Wonders of the Universe.

The news report went on to also include the LHC/search for the Higgs as also being partly responsible for the sudden popularity of physics.

I hope this is all good. Like I have said before, physics is too difficult to do for the wrong reasons. I hope that the LHC and Brian Cox are providing inspiration and new pathways that many students just simply didn't think of before, rather than just being enamored by the "celebrity" and "sexy news of the day".

Zz.

Physics And Sports

I've had many posts on here on how physics is applied to sports. This video presents a lecture on the relationship between physics (classical mechanics) and sports/games. It appears that this was given just before last year's London Olympics.



Zz.

Video of the Launch Control Center

A while back I posted photos of my visit to the Kennedy Space Center in Florida. I mentioned in that trip report of the rare visit to the Launch Control Center (or Firing Room), which is normally not opened to most people, much less, the public.

I've put raw video footage of that visit to the LCC on YouTube in case anyone wants to take a look at it. I've done no editing of any kind to it (thus the "raw" description). You'll get to hear a little bit from the tour guide in the background in some shots, but other than that, there's no narration.



Zz.

Linking A Particle's Mass To Time

This is rather surprising and unique.

A paper to be published in Science claims to have made a clock that measures time by linking it to a mass.

Abstract: Historically, time measurements have been based on oscillation frequencies in systems of particles, from the motion of celestial bodies to atomic transitions. Relativity and quantum mechanics show that even a single particle of mass m determines a Compton frequency ω₀ = mc²/ ħ, where c is the speed of light and ħ is the reduced Planck constant. A clock referenced to ω₀ would enable high-precision mass measurements and a fundamental definition of the second. We demonstrate such a clock using an optical frequency comb to self-reference a Ramsey-Bordé atom interferometer and synchronize an oscillator at a subharmonic of ω₀. This directly demonstrates the connection between time and mass. It allows measurement of microscopic masses with 4 × 10⁻⁹ accuracy in the proposed revision to SI units. Together with the Avogadro project, it yields calibrated kilograms. 

That's definitely an astounding accomplishment if this is verified. They actually could somehow get at the frequency associated with a particular mass.

A news report on this work can be found here, which reveals a bit more of the issue surrounding this measurement.

The idea for the clock stemmed from the quantum principle that particles also behave as waves, and vice versa. In particular, Müller and his colleagues wanted to determine how frequently the wave form of a single atom oscillates, a quantity that in quantum mechanics is inherently linked to the atom’s mass. Then the researchers could use those oscillations like swings of a pendulum to create a clock.

The snag in Müller’s plan was that it’s impossible to directly measure the oscillation frequency of waves of matter. The frequency of these waves is about 10²⁵ hertz, 10 orders of magnitude higher than that of visible light waves. So Müller and his colleagues came up with an apparatus that creates two sets of waves — one based on a cesium atom at rest and another on the atom in motion. The researchers measured the frequency difference between the waves and then used that number, a manageable 100,000 hertz or so, to calculate the much larger oscillation frequency of cesium at rest.

Let's see this will work out.

Zz.

Physics - The Second Most Demanding Major?

We have had reports before on studies or surveys that convey the idea that physics is a difficult subject. Some would even say it is the most difficult subject.

This blog post on Physics Central reports on a survey of students of various majors. One of the survey question is on how much time the students spent per week studying the subject. Physics majors came in 2nd, just behind engineering, in the number of hours per week studying the material.

According to a survey of hundreds of thousands of college students in the U.S. and Canada, 36 percent of physics seniors spend 21+ hours preparing for class every week. Only one other group out-studied the physics majors: engineering students. 42 percent of engineering seniors devoted 21 or more hours to studying every week.

There are more to the survey than just this, so you can read the rest either in that blog, or from the actual survey itself.  And you can draw your own conclusions from them.

Zz.

LHCb Result Published

Hey, remember when I highlighted the recent result from LHCb where it could not find any hint of anything beyond what the Standard Model predicted? The paper on the result has now been published in PRL and you can get free access to it from the link in this review.

Zz.

How Not To Teach Physics?

This is an interesting article written by former U. of Ottawa professor Denis Rancourt (you may want to read a bit of his history with his former university). Certainly, article that appeared on this Dissident Voice webpage consistently challenge the establishments and the established notion. I have zero issues with that. However, I question the validity of many conclusions, especially when it is only backed by anecdotal evidence. And just because someone questioned the conventional way of doing stuff does not make him/her immune from being equally questioned for the conclusion he/she is drawing.

Rancourt wrote on how ineffective the standard method of teaching physics is at imparting physics knowledge to students. Certainly, there have been plenty of studies to indicate that such dull methods of teaching is not every effective. He then described how he did it is own way and how, in his opinion (and the opinion of his TA), it showed an improvement.

I told the students to close their books and not read them, unless they thought they might find something of interest in there that they wanted to know. I told them they could look anywhere they wanted and ask anyone questions to find what they wanted.

I told them that first we needed to figure out what was worth knowing, and what it means to know.
I got blank stares. They worried about how they would be graded in such a system. They wondered what I really meant and what did I want them to do. But they gave me a chance and, luckily, I didn’t know what I was doing, so it was quite authentic.

So I said: “Let’s see. There must be every day things that we want to know, that we can understand…? Things we are curious about?”

They couldn’t find any. Some of them said they had a lot of work to do in their other classes so they did not want me to be too demanding. Many shared that view. But as the conversation continued and as it became clear that, well, it was a conversation; they relaxed. But they still could not think of anything they wanted to know, beyond the latest homework in the other courses. Sad really.

So I said: “Why is the sky blue?” “No really, how does that work?”

Well many of them had heard something about that in high school so we started a class-wide discussion about how and why the sky is blue. And for every answer that did not quite work, we were able to find a flaw in the answer, or a dead-end, where the word answer was not really explaining anything beyond “something something”.

I told them that it maybe had something to do with why the evening sky can be red and also asked why clouds are white, when they are not red.

So this led us to what is light…? Now you can spend a lot of focused time asking yourself what light is if you want to know why the sky is blue. So I discovered… I helped them see, through questions, what it was to truly know or understand something versus just repeat the words… that they could search and explore and critique themselves. So they did.

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And we had a final examination. And, honestly, it was like no final examination I had ever seen before. It was the opposite of depressing and fun to grade. It was full of intelligence and independent thought and evidence of significant research. I had a sense that the students had understood things, could explain them, and owned their knowledge.

I went back to the previous year’s examinations and saw a huge difference. I lent the two piles of examinations to the TA and she concurred that, yes, there was a significant qualitative improvement that could not be denied.

Now know that I was not comparing “bad” teaching to “anything would be better than that”. I was considered one of the best traditional method teachers, by the usual standards. So I was comparing certified bad teaching to something much better.

Now, there's a number of issues here that were not tackled:

1. Many physicists today were taught using the "conventional" methods. I was one of them. While one can argue that these may not have been the best technique, one cannot argue that WE, as a group, didn't learn any physics from them. In fact, I will vehemently argue that my E&M instructor was one of the best teacher that I've ever had and left his permanent imprint on me on how I learn things in physics. He taught things in a conventional means, but he was damn good at it. So then, is the problem here the philosophy of teaching, or the EXECUTION of that philosophy, i.e. how such conventional teaching is presented? Was Rancourt's ineffectiveness  in making the student learned early on a problem of the philosophy of teaching, or was it because he simply was not a good teacher executing that philosophy or methodology? I'm not saying he isn't, but this is something we don't know.

2. How effective is his new "technique"? Sure, anecdotally, he could claim that the exam results were better. But this is not how we arrive at things in science. Educational research requires quite a number of sampling, testing, and controlled groups for comparison. One simply can't claim one has discovered something better simply via such anecdotal evidence.

3. Note that other countries, especially Asian countries such as Korea, Singapore, and China, have continually produced masses of students that have tested higher in math and science. As far as I can tell, their teaching and learning techniques are still heavily "conventional" and not approaching anywhere near what Rancourt is doing. So why are these kids able to learn and understand physics?

I fully understand the desire to do things differently. After all, I've written extensively on how I would revamp the undergraduate intro physics labs to fulfill various goals. However, until that is properly tested, I would not make any kinds of claim of its effectiveness, because I'll just be doing what I've criticized a lot of people have done - relying solely on anecdotal evidence before proper, scientific and more-verified evidence are available. And people who dissent should not be quick to dissent by lowering their standards of what can be accepted to be valid.

Zz.