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

Kinker
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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?
 
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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.
 
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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?
 
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@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.
 
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