Can Quantum Tunneling Cause Objects to Instantly Swap Places?

In summary, if there's an object present on the far side of the barrier, it will contribute to the Hamltonian in ways that may either increase or decrease the probability of the tunnelling particle being found in the vicinity of the object.
  • #1
durant35
292
11
Hello guys,

I have few questions about the well-known quantum tunneling.

I'll start off with the animation from wikipedia
Quantum_Tunnelling_animation.gif


So question #1 why doesn't the barrier collapse the wave function, is that even possible? What's the difference between the barrier and the measurement screen in double slit experiment which collapses it when the behavior of the particle is clearly similar (moving towards the object)

Question #2: the wavefunction of any object has a small component on the other side of a barrier that it classically cannot pass. So for instance, theoretically, there's a non zero chance that some object from my room instantenously appears in the other room. What would happen with some object on the other side which before the tunneling act was in a location x which the tunneling objecg would occupy during the act of tunelling, how would the "spatial overlap" of those 2 objects be avoided?

Thanks in advance.
 
Last edited:
Physics news on Phys.org
  • #2
durant35 said:
So question #1 why doesn't the barrier collapse the wave function, is that even possible? What's the difference between the barrier and the measurement screen in double slit experiment which collapses it when the behavior of the particle is clearly similar (moving towards the object)?
The explanation depends on which interpretation you choose. The easiest approach, by far, is to select an interpretation in which there is no collapse so then there's nothing to explain. However, if you do want to use a Copenhagen-like interpretation that includes collapse, the explanation is that screen is a classical object so the von Neumann cut goes below it. (If you don't like that explanation, that's OK. There's something not to like about every interpretation).
Question #2: the wavefunction of any object has a small component on the other side of a barrier that it classically cannot pass. So for instance, theoretically, there's a non zero chance that some object from my room instantaneously appears in the other room.
Kinda sorta... But there's also a non-zero chance that all the randomly moving air molecules underneath my chair will, by random chance, happen to all be moving upwards at the same time. This would blast me and the chair through the roof like a rocket. That's not going to happen... and it's enormously less improbable than what you're describing. Also take a look at this Insights article: https://www.physicsforums.com/insights/you-will-not-tunnel-through-a-wall/
What would happen with some object on the other side which before the tunneling act was in a location x which the tunneling object would occupy during the act of tunneling, how would the "spatial overlap" of those 2 objects be avoided?
If there's an object present on the far side of the barrier, it will contribute to the Hamltonian in ways that may either increase or decrease the probability of the tunnelling particle being found in the vicinity of the object. You'd have to specify the exact conditions and then solve Schrodinger's equation for those boundary conditions - the wikipedia animation you posted will no longer describe the situation.
 
  • #3
Nugatory said:
If there's an object present on the far side of the barrier, it will contribute to the Hamltonian in ways that may either increase or decrease the probability of the tunnelling particle being found in the vicinity of the object. You'd have to specify the exact conditions and then solve Schrodinger's equation for those boundary conditions - the wikipedia animation you posted will no longer describe the situation.

That sounds logical and intuitive. My question was directed to the hypotethical case where the concept of instanteneous tunelling would actually occur and the object in question would tunnel to a location where it would necessary have to push out another object because it would, in a lack of better phrase, took its spot. So considering that, would the pushing out of the mentioned object and tunneling of our original object happen instanteneously and not in order original object tunnels to location x (cause)
-> object that was at location x gets pushed out (effect).
I hope I am being clear regarding the problem. Any suggestions are welcome.
 

1. What is quantum tunneling?

Quantum tunneling is a phenomenon in which a particle can pass through a potential barrier even when it does not have enough energy to overcome it, based on the principles of quantum mechanics.

2. How does quantum tunneling occur?

Quantum tunneling occurs when a particle's wave function extends beyond the barrier, allowing it to have a small probability of being on the other side of the barrier. This is known as tunneling probability and is dependent on the barrier's width and the particle's energy.

3. What are the applications of quantum tunneling?

Quantum tunneling has various applications in technology, such as in scanning tunneling microscopy, which allows for high-resolution imaging of surfaces. It is also used in tunnel diodes, which can switch at high frequencies and are used in electronic circuits.

4. What is the difference between classical and quantum tunneling?

In classical mechanics, a particle needs enough energy to overcome a potential barrier, while in quantum mechanics, a particle can pass through the barrier even with insufficient energy. Additionally, in classical mechanics, the probability of a particle passing through a barrier is always zero, while in quantum mechanics, there is a non-zero probability due to the wave-like nature of particles.

5. Is quantum tunneling a real phenomenon?

Yes, quantum tunneling has been observed and studied extensively in various experiments, confirming its existence. It has also been successfully explained and predicted by the principles of quantum mechanics.

Similar threads

Replies
14
Views
1K
Replies
4
Views
759
Replies
13
Views
2K
Replies
5
Views
983
Replies
1
Views
648
Replies
2
Views
1K
Replies
19
Views
960
Replies
4
Views
2K
  • Quantum Physics
Replies
33
Views
3K
  • Quantum Physics
Replies
13
Views
1K
Back
Top