What Is a Particle?
quantamagazine.org
quantamagazine.org
Much of physics is just describing how our world behaves, not what our world is.
To me, It's depressing that all the physics we know could be thrown away with one discovery.
As a lay person, it seems useless to spend too much time learning what we currently know.
It's like becoming well-read on the latest theories of copernicus only to have Isaac Newton blow the whole thing up.
It's great if you're a physicist. It opens doors to new work.
But not so great if you just want to know what it is and how does it work.
It hasn't happened in a while, though.
Whenever we peel back a layer to discover new physics, the old models are never lost, since the new models must necessarily reduce to those in more familiar situations!
Another factor is that as we learn more physics, as important as it might be to find answers, it is even more important to understand how our previous questions/notions might have been naive, and what might be better concepts with which to formulate our models. The variety of perspectives on the meaning of a “particle” merely illustrate that fact, applied to a naive word/concept that we’ve strung along for a long time.
Oh, physics grad school, never change.
https://news.ycombinator.com/item?id=24131831
The author (somewhat of a crackpot!) writes:
>"In classical physics, you have the particle/wave duality. Basically, one is the other, depending on frame of reference.
That particle wave duality (I've determined) is actually a particle/wave/field TRINITY.
That is, particles ARE waves (depending on how you look at them), waves are particles (depending on how you look at them), BUT ALSO waves are fields (depending on how you look at them), and fields are waves (depending on how you look at them), and fields are particles (depending on how you look at them) and particles are fields, again, "depending on how you look at them".
Google "Starlings". A single starling at rest is a particle, in motion, it's a wave, and many of them together moving in unision, that's a field.
Also (and this is the advanced lesson), you can have various degrees of recursion in this, for example, a whole field of starlings could be viewed as a single particle, then that could comprise multiple particles if teamed up with other fields of starlings, and then those things could move like wave.
Think nested particles/waves/fields -- inside of other particles/waves/fields.
Also, the smallest unit of space (to implement all of the others), DOESN'T NEED TO PHYSICALLY MOVE; that is, it only needs to state-change, like a pixel, if it were a magnet, it could change from a North Pole to South Pole (or possibly neutral), if charged, the charge could go from positive to negative and back, if a region of force, the force could push one way and then the reverse, etc., etc."
PDS: I don't know; but the author of that post sounds like a crackpot, and pretty delusional to me...
(Oh, wait a second... I'm the author of that post! <g>)
(I resemble that remark! Doh! <g>)
Of course there is the other sense of particles in metaphysical domains, such as the 'holes' in semiconductor physics, which cannot be directly measured but can be implied
Or to quote yourself: "Anytime someone insists on HN that virtual particles are real, you can just tell them that Arkani-Hamed disagrees with you and that he is also smarter than you."
There you go. Anytime someone insists on HN that virtual particles are real, you can just tell them that Arkani-Hamed disagrees with you and that he is also smarter than you.
Although people usually do not get hung up on the virtual particles. Rather people get annoyed when we say that the definition of a "particle" is "excitation of a quantum field".
I believe mind is a particular form of process on information, but that doesn’t mean all processes on information are minds. This IMHO is the fundamental error at the heart of panpsychism.
You have an apple in one hand. Since
1 = 1/2 + 1/4 + ... + 1/2^n + ...
I think that a lot of confusion arises because of the innocuous seeming equal sign. Explicitly replace the equals by approprate (algebraic) maps, and at least for me, the relationship becomes a lot clearer.
Maybe more familiar to HN, maybe it helps to do "typed" math? E.g. counting numbers have a different type than equivalence classes of Cauchy sequences. From a set theory perspective, it makes sense to ask the question whether the number 3 (as a set) equals the collection of triangles in R^3 (as a set). Of course, the two aren't equal, but it seems weird to even ask this question.
Maybe it should be just as incongruous to say that some vacuum state equals it's decomposition into virtual particles. The two things are just differently-typed. You need some computation to convert between them.
So, argument from authority then?
Are all experts in agreement on virtual particles? If not, which are we meant to 'follow'?
And BTW, I have no position on virtual particles.
> Are all experts in agreement on virtual particles? If not, which are we meant to 'follow'?
?
the person I was responding to picked out one particular expert's view
"you can just tell them that Arkani-Hamed disagrees with you and that he is also smarter than you."
aside from the silly "he is also smarter than you", just because one expert holds a view doesn't make it right.
If all the experts were unanimous, and the particular point had been well tested, then a point like yours would hold.
Also, the comment I was responding to was assuming that no-one on HN has a relevant background for having a solid opinion on virtual particles. I certainly don't, but I would not make that assumption about everyone on this forum. I don't agree with the notion that just because someone has a high status in a field that this automatically makes their opinions superior to other people in that field.
If elements of the universe have probabilistic distributions until observed, you have also a dualism there: 1) the observable element 2) the probabilistic structure surrounding it. Both are mystical and interdependent.
Maybe the particle and observation seems more real, but they both adhere to structure that surrounds and shapes them fully too. What we observe though is not particles themselves, but after-effects of the fleeting mirage. So everything is a copy, thus holographic nature.