Re:A meteorite hit the moon during yesterday's total lunar e...
by jessriedel on Wednesday January 23, 2019 @08:58AM
(#18978110)
> My understanding is that chaotic systems are still deterministic,
Classical chaotic systems are indeed deterministic in principle, and only effectively unpredictable due to finite measurement precision. But the world isn't classical, it's quantum, and quantum systems are fundamentally indeterministic.
(You can make a philosophical move where you say the wavefunction is deterministic even if the results of our measurements are indeterministic, and the wavefunction is the "real" thing, but that's orthogonal to the point I'm making. All I'm saying is that the meteor's path, on long enough timescales, is random in the same sense as radioactive decay.)
> "Irreducible quantum uncertainty" is something else that has nothing to do with Lyapunov time.
I think I'm going to have to pull rank on you and just say you're wrong on this one :) There's a whole field of quantum chaos that explores the relationship between these things in depth. Here's one of my favorite papers:
> I also see Lyapunov died in 1918,[1] while the uncertainty principle was introduced in 1927.[2]
I'm discussing the implications of chaotic dynamics for quantum systems, and scientists generally do not live to see the implication of all their ideas. Maxwell realized that light is just vibrations in the electromagnetic field, and he died in 1879, yet we still start by writing down Maxwell's equations when learning how light operates under the laws of quantum electrodynamics.
Classical chaotic systems are indeed deterministic in principle, and only effectively unpredictable due to finite measurement precision. But the world isn't classical, it's quantum, and quantum systems are fundamentally indeterministic.
(You can make a philosophical move where you say the wavefunction is deterministic even if the results of our measurements are indeterministic, and the wavefunction is the "real" thing, but that's orthogonal to the point I'm making. All I'm saying is that the meteor's path, on long enough timescales, is random in the same sense as radioactive decay.)
> "Irreducible quantum uncertainty" is something else that has nothing to do with Lyapunov time.
I think I'm going to have to pull rank on you and just say you're wrong on this one :) There's a whole field of quantum chaos that explores the relationship between these things in depth. Here's one of my favorite papers:
https://arxiv.org/abs/gr-qc/9402006
> I also see Lyapunov died in 1918,[1] while the uncertainty principle was introduced in 1927.[2]
I'm discussing the implications of chaotic dynamics for quantum systems, and scientists generally do not live to see the implication of all their ideas. Maxwell realized that light is just vibrations in the electromagnetic field, and he died in 1879, yet we still start by writing down Maxwell's equations when learning how light operates under the laws of quantum electrodynamics.