Wednesday, 14 June 2006

Another dangerous idea infecting classrooms

Scientist Travis Norsen has a warning about "a dangerous enemy [that] has infiltrated our science classrooms and is infecting our students’ minds."
The enemy is a profoundly unscientific theory masquerading as legitimate science. Its presence in the science classroom blurs the distinction between real science and arbitrary dogma and “makes students stupid” by leaving them less able to distinguish reasonable ideas from unreasonable ones – a skill that is surely one of the main goals of teaching science in the first place. You probably suspect the enemy I'm talking about is Intelligent Design . . .

The enemy I'm worried about is something else – something just as unscientific as Intelligent Design, but more dangerous because it is not widely recognized as such: the Copenhagen interpretation of quantum mechanics. . . This may seem like a rather technical issue that physicists should straighten out for themselves, an issue that those outside of physics shouldn't or needn't worry about. But the wider academic community – and, indeed, society at large – has a legitimate interest and stake in this issue, just as it has a legitimate interest and stake in the debate over Intelligent Design. Like Intelligent Design, Copenhagen quantum mechanics “makes students stupid.” Like ID, it probably has no place in college science classrooms.
Strong words. Go here and see if he can back them up.

LINKS: Unintelligent design, Part 1 - Not PC (Peter Cresswell)
Intelligent design in the physics classroom? - Travis Norsen, Journal of the American Physical Society, July 2006
Travis Norsen's Objective Science site
Cartoons by Nick Kim

Science, Education



Blogger Berend de Boer said...

Arggh, danger, infiltration of the minds of our kids, get the government working to get the mind of our kids straighted out!

14 Jun 2006, 14:35:00  
Blogger Berend de Boer said...

The author talks about "our" class rooms, which bring visions of state control to the mind.

Anyway, on the particulars: as I understood it, his particular theory has some appealing aspects and solves certain issues, but hasn't much advanced since David Bohm worked on it. If I remember correctly, issues of particle creation are not dealed with.

And does his particle and wave deal with paths that go backward in time? I doubt it.

I haven't had a real philosophical issue with it since I understood that it's all about adding all possible paths. How particles actually "known" all possible paths is an issue, but not a particle versus wave dilemma.

14 Jun 2006, 14:53:00  
Blogger noizy said...

since when did the "Copenhagen interpretation of quantum mechanics" feature in the school curriculum?

14 Jun 2006, 15:21:00  
Blogger Berend de Boer said...

It did in mine. But I didn't go to a state school...

14 Jun 2006, 18:58:00  
Blogger Brian S said...

Absolutely agree about the Copenhagen Interpretation. It is a load of positivistic nonsense. However the de-Broglie Bohm interpretation is pretty much many worlds in disguise; see here for example.

14 Jun 2006, 20:07:00  
Blogger noizy said...

> It did in mine.
> But I didn't go to a state school...

and presumably private schools can teach what they like, as long as they cover the curriculum requirements?

never spotted any quantum theory in my time at high school (admittedly, getting onto a couple of decades back now).

14 Jun 2006, 20:09:00  
Blogger Berend de Boer said...

James, I didn't go to a school in NZ. I went to a very religious school in The Netherlands. They have school vouchers, so everyone can choose whatever school they like. But they have a school curriculum of a sort, everyone has to do the same final exam, so schools generally make sure they cover that.

Quantum mechanics wasn't part of the end exam, but nonetheless was covered by fascinated teachers. But it was only after I read Feynman that I finally good make sense of it all.

But I'm on the board of a NZ private school, and I don't think we have any curriculum requirements. We don't offer NCEA, so as far as I'm aware we have no requirements whatsoever. Unfortunately I doubt we offer anything at QED level.

15 Jun 2006, 12:21:00  
Blogger PC said...

I do remember QT being touched on in seventh-form physics when I was at school, and that was at a school that would hardly be considered academic.

But I think Travis' point of relating QT in uni physics classrooms to ID in high school biology classrooms -- which is the analogy I understand him to be drawing -- is an appropriate rhetorical poiont to make.

15 Jun 2006, 16:22:00  
Anonymous Falafulu Fisi said...

Travis Norsen is far wide wrong to lump together Intelligent Design (ID) and Quantum Mechanics (QM) as in the same category. QM is a real science while ID is not a science at all. QM has provable hypotheses, which leads to other hypotheses where they are testable (experimental proof), while ID has hypotheses that can't be test at all. Travis Norsen's problem is that he clings to the words of Neil Bohr. Neil Bohr made a comment when no one really understood what particle was and what wave was. So, his comments, since the development of QM in the 1920s can be ignored. Physicists don't use the Copenhagen Interpretation to discover semiconductor devices which is part of every modern electronic gadgets on the planet contains, such as computers, cell phones, medical lasers, radio, TV, etc,... As Physicist Lewis Little made a comment about Copenhagen Interpretation, that had the technology of the last half a century (from 1950s onwards) available at the time when QM was formulated (1923), the interpretation would have been different.

The laser was invented in late 1950s by Townsend (Nobel Prize Winner), but it has long been proposed by Einstein in a paper he published in 1916 predicting that it is possible in nature that energy distributions of an ensemble of particles can reverse (invert) , where more particles from lower energy states are elevated to the higher levels, and fewer of the higher level particles are dropped to lower levels. At any instant of time, there is always a very high proportions of the total particles are at higher levels and very very small proportions that are occupying the lower levels. When the population of the higher-level particles are releasing their energy (photons), it resulted in huge flux of them that is so intense. Those particles that have just dropped to the lower energy levels as a result of their just being releasing a photon each, are pumped back up again by an external source (electrical current) so that they jump back to the higher-level state. The next de-excitation round, some particles will release a photon each (again generating very tense radiation) thereby dropping to lower energy level, and the pumping is repeated. This process goes on and on and one, till the laser is turned off. A simple analogy of this lasing phenomenon is that every society has less people who are rich and more people who are middle class or poor like pyramids. Einstein’s proposal is that if the population is inverted or reversed (invert the pyramid) in that there are more rich people than poor people such that the society contains about 98% Bill Gates type people and 2% homeless. Suppose there is a global donation to some disaster somewhere, and the amount of money fluxing into donation centre will be huge at one go, but we know that Bill Gates is not going to be poor if he gives $100 millions to Cancer Research. His business (external source) will always pumped back money into his wallet, for his next round of donations. At room temperature, roughly 2% of random sample of particles are in the higher energy states and 98% occupy the lower states. Einstein recognised that if this distribution is to be reversed and keep pumping (exciting) the higher populations with external energy source, and de-exciting them simultaneously, there will be a huge flux of photons (laser rays). Unfortunately, Einstein died in 1955 where laser was invented a few years after and didn’t live to see his prediction that indeed nature itself does allow such process to take place. Laser is the corner stone of everything today. Ipod, Computer, CD player, medical instrumentations, airport security scanning systems, supermarket barcodes, and so forth.

With the invention of laser, performing of Quantum Mechanics (QM) experiments for the double slit were able to confirm some of the bold assumptions made by Bohr (however sound absurd it was). The use of laser in the double slit experiments that something never available at the time when QM was formulated in 1920s. A laser beam is shone thru the double slit and the interference pattern is observed behind a fluorescent screen. This is the wave property, since wave interferes. Laser is then tuned down to emit one particle per every 5 seconds (rate can be varies by turning a knob) and leave it to run over an hour. The amazing thing is, after an hour this single particle emission has build up on the screen still shows interference pattern. This can’t be since; a single particle cannot interfere with itself? It is expected that the interference should have disappeared and thus form a bell-curve type of intensity distribution on screen, centring thru the line of sight from mid way between the slit holes to the screen. It should have been a maximum intensity in the middle, and fades away to either sides of the middle. Now, this is what exactly Neil Bohr was saying. The observer decides what he is going to see. Even the emission rate is tuned to shoot out one photon per every 5 seconds, it is still a wave since the observer has no way of knowing the trajectory each photons travels since leaving the laser source. Definition of a particle in Newtonian Mechanics is an object that has defined trajectory in its motion. Now, if the set-up is changed to put 2 photo-detectors in front of both slit holes (lets called them hole A and hole B), to register a beep sound when each photon passes thru in either A or B ? Such a sequence can be :

Photon number : 1 2 3 4 5 6 7 8,…
Hole Location : A A B A B B A B,…
OK Neil Bohr says, since the observer now is going to have knowledge about the trajectory of the particles because of the photo-detectors that give beep sounds of which hole that particle 1, goes thru, which hole that particle 2 goes thru, and so forth, the observer is deciding that he is measuring a particle and surprisingly that is exactly what is observed at the screen, a perfect bell-shaped distribution of intensity on the fluorescent screen. It is similar pattern if you shoot a stream of bullets into a steel wall with 2 holes separated by say, half a meter or so. Suppose that there is a plywood screen behind the steel wall. You can find out by checking the plywood after shooting that there will be more bullets that embeds in the middle point that is aligned directly with the mid-point between the 2 holes. Lewis Little says that if the screen is moved back and forth relative to the slits then the interference patterns shifted the locations of maximum and minimum intensity, which is something not done by Bohr in their days.

So, we must accept that Neil Bohr had proposed what Physicists always do all the time, 'leaping to make bold assumptions'. Wave & Particle concepts, even they were well understood in Newtonian Mechanics before the birth of QM, it was a revolutionary discovery when QM found out that the two are interchangeable. It is a human nature to make bold assumptions about something that is completely new and unfamiliar to you. Over time, with advance of technology to provide modern experimental set-ups to conduct more precise experiments and tests, the established views then can be changed, modified or thrown out. If that were the case, then humans would have invented the "Theory Of Everything" (TOE). So, I think that Travis is a bit sensational in picking on QM as unscientific. Neil Bohr made observations, which were correct, followed by 'bold assumptions'. One of those bold assumptions was the 'Complementary Principle' (CP), in which Travis thinks it is unscientific. Travis is bullshit here. CP is correct (observations) and it has never been refuted experimentally upto today. I mean that there has never been ever any experiment that has been conducted to prove that you can measure the particle property and wave property simultaneously. If the observer decides to measure the particle property, that is what he's going to observe. If the decides to measure to measure the wave property, that is what he's going to observe. He can never ever do a single measurement to detect both at the same time; it is always either this or that property (complementary). So, CP is taught at final year University QM course because they belong there, but to compare QM to ID, I think Travis has made an error there (I think a big error). I have to say the Bohm, John Bell, and others have tried to theoretically and experimentally proved that QM is philosophically corrupt, but they have failed. I agree that words (philosophical descriptions) describing QM has problems but the Maths is correct, so that is why Physicists keep inventing new gadgets since they don't put too much weight to the Copenhagen Interpretation, they just put much weight to the equations which give them results.

Here is some interesting reading from Roger Penrose:

“Quantum Concious”

17 Jun 2006, 04:02:00  

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