B Quantum theory for high-school students

[diPoleMoment]

http://www.igpp.ucla.edu/people/mkivelson/Publications/025-JA080i025p03525.pdf

So this takes splitting of the drift velocity shell, are the quantum theories applicable or am I totally dense, opaque :)

 

[Dadface]

This thread seems to be going further and further beyond basic high school level. Just saying.

 

[PeterDonis]

Thread closed for moderation.

 

[PeterDonis]

This thread seems to be going further and further beyond basic high school level. Just saying.

And as a result, several technical discussions have been moved to new threads.

This thread is now reopened. Please keep discussion here limited to the specific topic of the teaching of quantum theory at the high school level.

 

[bhobba]

Well, apparently even Purcell and Feynman didn't understand relativity, years after Einstein and Minkowski established it, and after QED was already successful. So if they didn't understand it, why should we bother now?

I doubt that eg the Feynman Lectures On Gravitation. He didn't like going to gravity conferences but do not confuse dislike with lack of understanding. And even then guys like Kip Thone claimed he had some rather non-trivial discussions with Feynman about GR. You can find out exactly what he did not like about gravity conferences here:
https://www.amazon.com/dp/0393340651/?tag=pfamazon01-20

BTW Feynman always claimed given what Einstein knew he could never have discovered relativity. I think he was referring to both the Special and General.

Of relevance here however is what should be taught at HS. IMHO its done all wrong here in Australia and the IB program - these are the two I know best.

You need a calculus based general physics course not only because the physics is explained better, but it reinforces what you learned/are learning in calculus. If you want to torture students you could use the Feynman Lectures - but most students are not in the class to get the most out of those three volumes at HS - a few could - but not the majority. Something like the following would be best for them:
http://www.physics2000.com/Pages/About.html

I know that book - its not too bad - but the QM bit needs to be supplemented by the teacher explaining, like most books about basic QM, its semi-historical. They should mention it will be changed later to something more modern as your physics education progresses.

Thanks
Bill

 

[bhobba]

So I am going simplistic, so pardon if it is way off. Once an object is in motion it will remain in motion until an equal and opposite force stops it. If there is no mass that is calculatingly significant, wouldn't this still be true?

This is off - topic - please start a new thread to further discuss it if interested. But just a comment here - Newtons first law of motion actually follows from symmetry considerations - see - Landau - Mechanics - and the modern basis of classical physics - the principle of least action which follows from QM. Actually both the first and second law, as usually stated, are vacuous - but again a new thread is required.

But please, please if you want to discuss that start a new thread - and to answer your question - yes it would still be true - but explainig the details - please - not in this tread.

Thanks
Bill

 

[bhobba]

So read the Neother theorem pdf and it is way above my head. Math was never a strong point.

Start a new thread at the B level about Noether. Me and others can explain it to you at that level, plus the very interesting history behind it.

It is one of the most important theorems of modern physics, and needs to be more widely known - especially by philosophers who by and large seem unaware of it.

Thanks
Bill

 

[thierrykauf]

The only reason, in my mind, why people start teaching quantum mechanics in high school, is not, sadly, because high school students suddenly became brighter, but because the amount of material needed to bring a student to the level of string theory is so large that you would need 48 hour days if you started in college :) I got a taste of this when I took a 4 semester graduate course on particle physics. The instructor told us "Your physics education stopped at 1926. I'm going to bring it to 1994 (the year I took the course). Fasten your seatbelt." Just trying to keep up with string theory papers (Witten's monthly 100 page articles for instance) was a full time job. I can't imagine facing a college student who only knows classical physics! And the thing is, not only is there more to teach but it's much harder material. So it requires either brighter students or teacher, and probably both.

 

[cratylus]

One thing the lectures do not seem to explain is complex numbers; they start out by assuming the students already know about those. Is that a valid assumption for high school students?

Not just this but vectors of complex numbers and various notations for the same mathematical entity - so I doubt that pedagogically it would succeed.

 

[romsofia]

I think it's a pretty cool idea, but that section on Eigenvalues/vectors is uh... leaves a lot to be desired.

 

[QuantStart]

Maybe we should speak of "quarticles", a contraction of quantum and particles.

Sometimes in the beginning quantum class I encourage students to think of quantum particles as "quantons" , peculiar objects from the quantum world, which all share peculiar non-classical features. I saw this term in the book "Quantics" by Levy-Leblond & Balibar.

 

[vanhees71]

I doubt that eg the Feynman Lectures On Gravitation. He didn't like going to gravity conferences but do not confuse dislike with lack of understanding. And even then guys like Kip Thone claimed he had some rather non-trivial discussions with Feynman about GR. You can find out exactly what he did not like about gravity conferences here:
https://www.amazon.com/dp/0393340651/?tag=pfamazon01-20

BTW Feynman always claimed given what Einstein knew he could never have discovered relativity. I think he was referring to both the Special and General.

Of relevance here however is what should be taught at HS. IMHO its done all wrong here in Australia and the IB program - these are the two I know best.

You need a calculus based general physics course not only because the physics is explained better, but it reinforces what you learned/are learning in calculus. If you want to torture students you could use the Feynman Lectures - but most students are not in the class to get the most out of those three volumes at HS - a few could - but not the majority. Something like the following would be best for them:
http://www.physics2000.com/Pages/About.html

I know that book - its not too bad - but the QM bit needs to be supplemented by the teacher explaining, like most books about basic QM, its semi-historical. They should mention it will be changed later to something more modern as your physics education progresses.

Thanks
Bill

I don't think that you can use the Feynman Lectures in high school. They are full-fledged introductory physics books at the university level, and I'd say they are rather theory than experimental books.

Nevertheless I agree with you that physics in the final classes of high school should be taught calculus based, and I consider calculus a mandatory subject for any high-school student. Calculus must be consider a topic of general education for anybody at a high school, and indeed applications in physics are very nice examples for its applicability in real-world problems. In fact math is the key to almost everything in the modern world from the natural sciences and technology, including informatics to economy, sociology etc.

In other words any didactics, which tries to "avoid mathematics" in any STEM subject is flawed to begin with.

 

[bhobba]

Calculus must be consider a topic of general education for anybody at a high school, and indeed applications in physics are very nice examples for its applicability in real-world problems. In fact math is the key to almost everything in the modern world from the natural sciences and technology, including informatics to economy, sociology etc.

Here in Aus, fortunately, those in power recognize it. But we still have some, you see them every now and then - it's abominable that you can graduate university without a foreign language etc

But I am heartened most reject it as non-sense. Whenever I hear such I ask people I know from a wide spectrum of occupations - chefs to engineers and every single one just laughs their head off - how ridicules. But most - well while not quite the exact opposite recognize math as an absolute necessity - and that includes calculus. What do they think, by and large, is THE career of the future? Big Data. I explain the central limit theorem to them - they see its importance straight away - also those that do not know it are a little surprised - but I tell then - it's true - but you need calculus to prove it - and not the simple stuff at HS either. They get my drift and see the necessity of advanced math at university.

In fact on a discussion panel show called Q&A here in Aus they had a number of educators and I thought - we will get more of this language/humanities type stuff. To my total surprise and amazement we got complete agreement all degrees in the future must include a significant amount of math and the declining number of people here in Aus not doing calculus based math at HS has to be stopped - its a matter of the utmost urgency.

It both gladdened and surprised the bejesus out of me.

Thanks
Bill

 

[Dadface]

I think that one thing which is relevant to this discussion and which seems to have been overlooked is illustrated by the question:

What percentage of high school students move on to study physics in greater detail?

I don't know the answer but I'm confident in assuming that the percentage is very small, even for those who choose physics as one of their specialist subjects, (A level in the UK). We have to be mindful of this when planning curricula and what we teach must not be too specialised and biased in favour of one small group of students.

 

[bhobba]

I don't know the answer but I'm confident in assuming that the percentage is very small

Actually I think its not that small - remember you have to do it for other subjects like engineering, biophysics, computational physics etc.

Here is Aus combined physics/math degrees are popular. Where I went to they have a specific strand in the math degree for engineers and physics double degrees - it's called applied and computational and the subjects are particularly valuable to those type of majors eg they must do the following 4 subjects:
MXB321 Applied Transport Theory, MXB322 Partial Differential Equations, MXB323 Dynamical Systems, MXB324 Computational Fluid Dynamics

A double degree in physics and math is excellent preparation for many post graduate degrees eg engineering which is moving towards masters as the basic qualification, scientific computing etc. The real action these days is not undergraduate - its graduate. You get a feel for what you enjoy/are good at and can make a wiser choice of career/qualification with a good background that will help in many areas.

Thanks
Bill
https://www.qut.edu.au/study/structures/study-plan-data?unit-id=68861&SQ_DESIGN_NAME=content&fromajax=true

 

[atyy]

I don't think that you can use the Feynman Lectures in high school. They are full-fledged introductory physics books at the university level, and I'd say they are rather theory than experimental books.

Nevertheless I agree with you that physics in the final classes of high school should be taught calculus based, and I consider calculus a mandatory subject for any high-school student. Calculus must be consider a topic of general education for anybody at a high school, and indeed applications in physics are very nice examples for its applicability in real-world problems. In fact math is the key to almost everything in the modern world from the natural sciences and technology, including informatics to economy, sociology etc.

In other words any didactics, which tries to "avoid mathematics" in any STEM subject is flawed to begin with.

I disagree. Calculus should be taught in primary school. Otherwise, they are not going to get to the standard model by high school :P

OK, I concede that's a bit much. QED would be enough, but they must be taught the proper Wilsonian viewpoint.

 

[vanhees71]

I think that one thing which is relevant to this discussion and which seems to have been overlooked is illustrated by the question:

What percentage of high school students move on to study physics in greater detail?

I don't know the answer but I'm confident in assuming that the percentage is very small, even for those who choose physics as one of their specialist subjects, (A level in the UK). We have to be mindful of this when planning curricula and what we teach must not be too specialised and biased in favour of one small group of students.

This is a dangerous argument. Highschool education should not aim at a specialized preparation for any specific job but it should give a realistic view on all kinds of subjects from math, natural science to humanities and languages. The reason is that as a high school student you usually don't yet know what profession you'd choose for the rest of your life, and to decide this, you have to get some insight in all kinds of subjects. It's dangerous to specialize too early.

In Germany we have a big debates about and 16 (in my opinion not too good) solutions for school education for decades, one in each state of the federal republic. The debates always have their buzz words in hypes, leading to a lot of dicontinuity in developing good syllabi for the various subjects. Right now the big hype is about "digitalization", not only concerning school but in general. Germany is quite behind schedule with the basic infrastructure and what's called "fast internet" compared to other countries in the EU. Instead of concentrating on this infrastructural issue one debates it for ages.

Of course also the schools are quite backward concerning the hardware infrastructure and, even worse, in both the education of the teachers and consequently also developing the didactics and education material for all levels of the school education. Instead the politicians think it's all done when each student gets "fast internet" and a tablet and each class room some digital black board (called "smart board", as if the board has to be smart rather than the teachers using it...). It's really sad. It's widely overlooked that everything concerning IT rests on math and logics. To be able to use IT in a sensible way you still need all the classical skills of school education valued for centuries in the developed world: the ability to read and write texts and, most importantly, understand them as well as some foundations of math and logic. With the internet, if all the infrastructural necessities are fulfilled and it's available to all students and teachers, you also need the ability to critically judge information and figure out how to separate the "fake news" from the facts. Most of these skills can be taught as well with an old-fashioned black board as with most modern digital ones. The latter only provide more possibilities for visualization, helping to make abstract things clearer with graphics and animations not available by drawing on a traditional black board, but it needs first of all competent teachers who know, how to use it in a sensible way. Just showing YouTube movies is not enough!

 

[entangled physicist]

There is an interesting blog on the possibilities of quantum physics in high schools:
http://physicsbuzz.physicscentral.com/2019/06/quantum-physics-in-secondary-school-how.html
The cited article analyzes quantum physics in 15 different national curricula or educational standards:
https://journals.aps.org/prper/abstract/10.1103/PhysRevPhysEducRes.15.010130
It shows that there are a lot of possibilities to address this topic on the secondary level. It is not only possible in principle it is the educational reality in many countries.