Hacker News new | past | comments | ask | show | jobs | submit
"Particles" don't exist in the naive sense. What a particle is, is an excitation of a field. A "particle" is a dynamic pattern.
But that just kicks the can.

The modern record for a matter-wave superposition stands at a nanoparticle composed of roughly 7,000 sodium atoms (about 8 nanometers wide), achieving a massive "Schrödinger's cat" state at the scale of a small virus.

So then particles don't exist, and viruses also don't exist? Is "reality" just a dynamic pattern that doesn't exist in the naive sense? As astute stoics we should not worry ourselves with such matters, "shut up and calculate"?

There is something about quantum theory that is different in character from any physical theory posed before. To put a finger on it, the issue is this: The basic statement of the theory—the one we have all learned from our textbooks—seems to rely on terms our intuitions balk at as having any place in a fundamental description of reality. The notions of “observer” and “measurement” are taken as primitive, the very starting point of the theory. This is an unsettling situation! Shouldn’t physics be talking about what is before it starts talking about what will be seen and who will see it? Perhaps no one has put the point more forcefully than John Stewart Bell:

> What exactly qualifies some physical systems to play the role of ‘measurer’? Was the wavefunction of the world waiting to jump for thousands of millions of years until a single-celled living creature appeared? Or did it have to wait a little longer, for some better qualified system . . . with a PhD?

https://arxiv.org/pdf/1003.5209

> But that just kicks the can.

"reality" is just a picture painted on consciousness. A particle exists because consciousness, for some reason, perceive a particle. Physicists should stop looking for smaller particles, and look into space and time as something that emerge out of consciousness...

I think you’re asking physicists to pursue a fundamentally metaphysical question, no?
Look, imagine you are a scientists in a 3D shooting game, like Quake for example. And you want to figure out the fundamental reality. So in the game, you take game objects and look really close. You find that everything is made up of very small triangles. Then you very carefully slice out a single triangle, and shoots right at its center with some particle like thing from game. You find that something inside the triangle reflect the particle.

You are enthralled! "There is something there still!" you say to yourself.

But there is nothing there! The game engine just figured that the particle would collide with the triangle, and altered its velocity accordingly. But you are too caught up in your assumption that you do more experiments (I think this is what our physicists are doing in our world). But what ever you do, you can only observe the behavior implemented by the game engine, and not the game engine itself, or the computer that is running it....

But you can imagine it. You can imagine an explicitly implemented program and a computer with limited memory that is running it. And if you are allowed to consider it, they can do other experiments. Instead of looking into smaller and smaller things, you can look for other observations that might confirm this. Maybe you can go really far and see if they are not allowed to go beyond some threshold (Ref: The movie "The thirteenth floor").

And would that be pursuing something metaphysical?

particles exist independent of consciousness.
Can you describe what you mean by "exist"?

Without a common understanding of that word, any further discussion is useless..

This is a bit like saying the universe is made of tiny pink elephants, and arguing that this is only untrue in some “naive sense” because we redefined “tiny pink elephant” to mean “excitation of a field”. It doesn’t seem more naive to me to admit that the world is not in fact made of tiny pink elephants than it is to argue “yes it still is made of tiny pink elephants [but only because we redefined the term to match the evidence]”.