Is it possible to explain Quantum tunneling with the HUP?

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Discussion Overview

The discussion centers on the relationship between quantum tunneling and the Heisenberg Uncertainty Principle (HUP), specifically exploring the position-momentum and time-energy uncertainty principles. Participants examine whether these principles can adequately explain quantum tunneling phenomena, particularly in the context of nuclear fusion in stars.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that quantum tunneling can be explained using the position-momentum uncertainty principle, noting that as momentum uncertainty decreases, position uncertainty increases, allowing for the possibility of finding a particle in a potential barrier.
  • Another participant acknowledges that while the uncertainty principle can be used to explain tunneling, it is an oversimplification compared to more complete mathematical formulations of quantum mechanics.
  • A participant expresses confusion regarding the interpretation of the time-energy uncertainty principle, questioning why it should not be treated similarly to the position-momentum uncertainty principle.
  • One participant attempts to clarify that "time" is not an operator in quantum mechanics, suggesting that the time-energy uncertainty principle operates differently than the position-momentum uncertainty principle.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the adequacy of the uncertainty principles to explain quantum tunneling. There are competing interpretations and clarifications regarding the time-energy uncertainty principle and its relationship to the position-momentum uncertainty principle.

Contextual Notes

There are limitations in the interpretations of the time-energy uncertainty principle, particularly regarding its treatment as analogous to the position-momentum uncertainty principle. The discussion also highlights the complexity of nuclear fusion processes and the varying conditions required for different fusion reactions.

Nam Jeong Woo
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TL;DR
Quantum tunneling with time-energy uncertainty principle
I'm a student in South Korea(It is my first English question ever). I found descriptions of quantum tunneling explained by the uncertainty principle in Korea. There are two kinds of descriptions to explain quantum tunneling; position-momentum and time-energy uncertainty principle.

First, position-momentum uncertainty principle. When two protons collide, the uncertainty of momentum is decreasing, so the uncertainty of position is increasing. Therefore, it is possible to exist the probability of discovery in potential barrier <- is it the right description?

Second, time-energy uncertainty principle. Classically hydrogen needs more than 100 million degrees of temperature for nuclear fusion, but it isn't really the temperature inside the sun, is it? So, we can't go beyond the potential energy, but the time uncertainty is reduced when we look at that time of nuclear fusion, so energy uncertainty is increased and nuclear fusion is possible.

I want to know above all about the second description. These explanations are often found in Korea. But I couldn't find it when I looked it up in English. I wonder whether the explanation is correct.

Is it possible to explain quantum tunneling with the uncertainty principle?
 
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Nam Jeong Woo said:
Is it possible to explain quantum tunneling with the uncertainty principle?
Possible, yes, and that's one of the more common ways of explaining the tunnelling to a non-specialist. It's not exactly wrong, but it is an oversimplification of a more interesting and complete mathematical formuation of the theory.
Classically hydrogen needs more than 100 million degrees of temperature for nuclear fusion, but it isn't really the temperature inside the sun, is it? So, we can't go beyond the potential energy, but the time uncertainty is reduced when we look at that time of nuclear fusion, so energy uncertainty is increased and nuclear fusion is possible.
There are multiple different fusion reactions requiring different combinations of temperature and pressure, so a blanket statement like "needs more than 100 million degrees" is misleading. You don't really need to involve quantum mechaics to understand what's going on inside a star unless you're going to be making detailed quantitative calculations of reaction cross-sections, and that's more than most non-specialists are interested in.
 
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Thank you for your answer. But I can't understand the time-energy uncertainty principle. Some people said 'You should not interpret the time-energy uncertainty principle like the position-momentum uncertainty principle.' I don't know why I should not interpret so on. What are the differences between time-energy and position-momentum?

I interpret the quantum tunneling with the time-energy uncertainty principle as written in the above.
(Wave can't go beyond the potential energy(if the wave doesn't have the energy that crosses the potential barrier), but the time uncertainty is reduced when we look at that time when the wave close to the potential barrier, so energy uncertainty is increased and the wave can cross the barrier. )
But I can't be sure about this explanation because I don't know how to interpret the time-energy uncertainty principle. Is it okay to interpret the T-E as the P-M uncertainty principle?
 
Griffiths' textbook on QM explains this well in chapter 3.

Basically, the HUP is a general statement about operators. "Time" is not an operator in QM. So the Delta t resembles something else (the time it takes for the energy to change with one standard deviation).
 
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