B Does decoherence prevent 100% of quantum tunneling of macro object?

Click For Summary
Quantum tunneling of macroscopic objects is considered to have a very small but non-zero probability, despite the effects of quantum decoherence. The discussion compares this to a classical scenario where a table could theoretically break through a ceiling due to random air molecule movements, highlighting the extreme unlikelihood of such events. The probability of a chair-sized object tunneling through a wall is even less than this example. The conversation also touches on the distinction between theoretical possibility and practical reality, suggesting that while tunneling could occur, it is so improbable that it is effectively impossible in practice. Overall, the consensus is that while quantum tunneling is theoretically possible, it is not feasible for macroscopic objects.
Kinker
Messages
18
Reaction score
1
TL;DR
Does quantum decoherence absolutely prevent quantum tunneling of macroscopic objects?
(Decoherence) macro world and quantum world difference
Isn't the quantum tunneling probability of macroscopic objects always zero due to quantum decoherence? It may be possible in the microscopic world, but I always think it is impossible in the macroscopic world due to countless interactions. Isn't this the same in a universe with infinite time? So isn't the probability of a macroscopic object tunneling by chance always zero, regardless of the duration?
 
Physics news on Phys.org
Kinker said:
So isn't the probability of a macroscopic object tunneling by chance always zero, regardless of the duration?
No, it is a very very small non-zero probability.

Consider a similar purely classical setup: There is a table sitting on the floor in front of me, my feet are resting on it. The air molecules above and below it are randomly bouncing around from thermal motion. There is a very very small non-zero probability that all the air molecules above and below the table will just randomly happen to all be moving upwards at the same moment, and if this happens the table will blast its way through the roof like an artillery shell, ripping my feet off and leaving me with bloody stumps at the ends of my legs. The probability of this happening is something like ##2^{(10^{24})}##, we are comfortable saying that it's not going to happen.

The probability of a chair-sized macroscopic object tunneling through a wall is much much less than that.
 
Last edited:
  • Like
Likes vanhees71, Quantum Waver and Demystifier
Nugatory said:
No, it is a very very small non-zero probability.

Consider a similar purely classical setup: There is a table sitting on the floor in front of me, my feet are resting on it. The air molecules above and below it are randomly bouncing around from thermal motion. There is a very very small non-zero probability that all the air molecules above and below the table will just randomly happen to all be moving upwards at the same moment, and if this happens the table will blast its way through the roof like an artillery shell, ripping my feet off and leaving me with bloody stumps at the ends of my legs. The probability of this happening is something like ##2^{(10^{24})}##, we are comfortable saying that it's not going to happen.

The probability of a chair-sized macroscopic object tunneling through a wall is much much less than that.
Does that mean that macroscopic objects can also accidentally experience quantum coherence?
 
Last edited by a moderator:
@Kinker You are trying to distinguish between the propositions “It could happen but it won’t” and “It can’t happen”. I’m not sure they are distinguishable.
 

Similar threads

  • · Replies 20 ·
Replies
20
Views
3K
Replies
54
Views
7K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 45 ·
2
Replies
45
Views
12K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 22 ·
Replies
22
Views
3K
Replies
7
Views
2K
Replies
4
Views
2K
  • · Replies 40 ·
2
Replies
40
Views
8K