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Macroscopic quantum objects cannot exist if P ≠ NP?

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Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#3
post #2

The Navier-Stokes equations are also hard to solve, that does not stop fluids from obeying them.

I'm not totally familiar with the Navier-Stokes equations, but from what I've just read (please correct me if I'm wrong!), I think the difficulty of the Navier-Stokes equation is reasoning about the solution set, while with quantum constructions the issue is whether or not a solution exists for some specific macroscopic system.

Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#4
This hypothesis seems to rest in the flawed idea that quantum processes must unfold as if by a step by step calculation which consumes time, in the ordinary temporal dimension. And so certain complex state changes are impossible simply because they don't have enough time to execute within some predetermined slot, or something like that. Time in the simulation is not the same as time in the simulator. Come on, this is not even basic science as much as basic sci-fi! :)

Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#5
post #2

The Navier-Stokes equations are also hard to solve, that does not stop fluids from obeying them.

Also, how can N bodies orbit each other? Don't they know there is no analytic solution to their problem? Sheesh! (Maybe they are using floating-point?)

Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#6
I'm not buying it

1 - P=NP is a mathematical problem. It has nothing to do with Physics. Physics has to do with Mathematics but one should be very careful when extrapolating (range, constraints, etc).

2 - Nature has no problem whatsoever solving complicated equations. Our mathematical models are the ones who suffer to model simple everyday stuff in Physics. Turbulence and Navier-Stokes equations, electromagnetic propagation, the way lightning goes through the air, etc.

Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#8
I think the explanation for why we don't observe macroscopic quantum phenomena is rather more simple than that, and likely has more to do with the results of a superposition of a large ensemble of possible states than some fairly strained analogy with computation (think of it as something like fourier decomposition of a function).

Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#9

This hypothesis seems to rest in the flawed idea that quantum processes must unfold as if by a step by step calculation which consumes time, in the ordinary temporal dimension. And so certain complex state changes are impossible simply because they don't have enough time to execute within some predetermined slot, or something like that. Time in the simulation is not the same as time in the simulator. Come on, this is…

Surely Schrodinger’s Paradox implies cause and effect?

Re: Macroscopic quantum objects cannot exist if P ≠ NP?

#10
One part I didn't like is towards the beginning the author says: "Nobody knows why we don’t observe these kinds of strange superpositions in the macroscopic world. For some reason, quantum mechanics just doesn’t work on that scale. And therein lies the mystery, one of the greatest in science."

But I thought the reason we dont see macroscopic events exhibiting quantum superposition behavior was because of quanutm decoherence? It's just so hard to get a macroscopic situation that hasnt already been observed and collapsed.

But then the author kinda hints at this point later when he mentions: "Physicists have become increasingly skilled at creating conditions in which ever larger objects demonstrate quantum behaviour."

Am I missing something, or is he blowing the problem (and the impact of Bolotin's computational limit theory) way out of proportion?

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