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Greg Bernhardt
Oct21-03, 12:32 PM
Richard.P.Feynman once said "I think it would be safe for me to say that no one in this world understands Quantum Mechanics". Such an amazing theory Quantum Mechanics is, yet hard to understand. Quantum Tunneling has always been given in small portions of many text books and details have not been covered so as to aid better understanding of the Concept.In this article I have made an attempt to provide a better understanding of Tunneling. Go along read it...

http://physicspost.com/articles.php?articleId=173

chroot
Oct21-03, 02:39 PM
No offense to either you or Sridhar Narayanan, but I'm not very impressed. The writing is childlike and full of grammatical and syntactic errors. Why has he capitalized Potential Barriers and Electric Field?

His entire argument seems to come down to this statement:
The electron out of sheer curiosity tries to cross the potential and gets trapped inside the potential
....and needless say, I don't think this is a particularly elegant or even correct way of explaining this to anyone.

Don't you have any referrees Greg? Or at least a copy editor?

- Warren

Crisp
Oct21-03, 03:01 PM
Good to see you also say what's on your mind on this forum, Warren ;).

Bye!

Crisp

jcsd
Oct21-03, 04:11 PM
Most of it contents of the article could be summed up much more succinctly by simply saying: "quantum mechanical tunnelling allows the wavefunction to penetrate classically forbidden areas and hence pass through potential barriers" to say why it is the case you need a more comphrehensive and technical explanation.

Also it's a cardinal sin in physics to captilize the wrong letters ( while I'm at it use subscript otherwise it's diffcult to tell whether the number is for identification or whether it's a mutiple and you've assigned velocity and potential the same letter).

Adrian Baker
Oct22-03, 04:28 AM
Originally posted by jcsd


Also it's a cardinal sin in physics to captilize the wrong letters

I appreciate this to be the case for some values such as 'g' or 'G' but is it that important for written words? For example is it Physics or physics?

I'm not trying to be argumentative here, just not sure about the 'cardinal sin ' bit. Sadly, I had a modern 1960s education, where rules of grammar went out of the window and 'expression' was the important thing. As such I'd be interested to hear more about your statement above.
When is it just poor English (I can cope with that) but more importantly, when is it poor Physics?

jcsd
Oct22-03, 05:55 AM
No, for example he captialized, the v for velocity (he also had capital V for potential, which is correct), the m for mass (which is someimes acceptable though) and the p for momentum.

This makes equations a lot more difficult to read as you no longer know intutively which letter represnets which quantity.

shchr
Oct23-03, 05:00 AM
For everyone who are interested in quantum tunneling. Check this book!
Quantum theory of tunneling written by Mohsen Razavy, World Scientific Pub
This book describes how tunneling time may be defined and possibly speed of quantum tunneling is superluminal.

Integral
Oct23-03, 07:12 PM
The letter used for most physical quantities is unique an exception is k, it is used for both spring constant in Hook's Law and wavenumber in the wave equation, this can be a real nuisance when dealing with wave phenomena and springs.

jcsd
Oct25-03, 12:36 PM
Many physical quantities use the same letters: angular frequency and angular velocity, moment of force, mutual induction and luminous exitance, etc. Though physical constants do tend to have unique letters (though often shared with physical quantites). k is also Boltzmann's constant just to confuse things.