The distinction I tend to make is between physical using the classical definition of physics (where everything is made of particles basically) and the quantum mechanical physics which defies “physical” in the classical sense. So far we’ve only been able to scientifically witness quantum physics in small particles, but as you say, there’s no reason it can’t apply at a macro scale, just… we don’t know how to witness it, if possible.

it doesn’t require an observer to collapse the wave function

Or maybe it does? The explanation I have for us being unable to apply the experiments at a larger scale is that as we scale things up, it becomes harder and harder to avoid accidental observation that would taint the experiment. But that’s really no more than a hunch/gut feeling. I would have no idea how to prove that 😅

[–] Sombyr@lemmy.zip 2 points 7 months ago (1 children)

I see, so your definition of "physical" is "made of particles?" In that case, sorta yeah. Particles behave as waves when unobserved, so you could argue that they no longer qualify as particles, and therefore, by your definition, are not physical. But that kinda misses the point, right? Like, all that means is that the observation may have created the particle, not that the observation created reality, because reality is not all particles. Energy, for instance, is not all particles, but it can be. Quantum fields are not particles, but they can give rise to them. Both those things are clearly real, but they aren't made of particles.
On the second point, that's kinda trespassing out of science territory and into "if a tree falls in the forest" territory. We can't prove that a truly unobserved macroscopic object wouldn't display quantum properties if we just didn't check if it was, but that's kinda a useless thing to think about. It's kinda similar to what our theories are though, in that the best theory we have is that the bigger the object is, the more likely the interaction we call "observation" just happens spontaneously without the need for interaction. Too big, and it's so unlikely in any moment for it not to happen that the chances of the wave function not being collapsed in any given moment is so close to zero there's no meaningful distinction between the actual odds and zero.

[–] arendjr@programming.dev 2 points 7 months ago

Agreed on all counts, except it being useless to think about :) It’s only useless if you dismiss philosophy as interesting altogether.

But that kinda misses the point, right? Like, all that means is that the observation may have created the particle, not that the observation created reality, because reality is not all particles.

I guess that depends on the point being made. You didn’t raise this argument, but I often see people arguing that the universe is deterministic and therefore we cannot have free will. But the quantum mechanical reality is probabilistic, which does leave room for things such as free will.

I can agree with your view to say observation doesn’t create reality, but then it does still affect it by collapsing the wave function. It’s a meaningful distinction to make in a discussion about consciousness, since it leaves open the possibility that our consciousness is not merely an emergent property of complex interaction that has an illusion of free will, but that it may actually be an agent of free will.

And yes, I fully recognise this enters into the philosophical realm and there is no science to support these claims. I’m merely arguing that science leaves open a path that enters that realm, and from there it is up to us to make sense of it.

There is the philosophical adage “I think therefore I am”, which I do adhere to. I know I am, so I’ll consider as flawed any reasoning that says I’m not. Maybe that just makes me a particularly stubborn scientific curiosity, but I like to think I’m more than that :)