# The two paradoxes of point-like nature

Discussion in 'Physics & Math' started by Trapped, Feb 17, 2014.

1. ### Aqueous Idflat Earth skepticValued Senior Member

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Fields add, they do not interact. You can't overrule nature no matter how hard you try.

3. ### TrappedBannedBanned

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You don't seem to have a clue what you are talking about. By ''add'' I presume you mean something mathematical. Stop trying to remember equations and just do a google search on whether or not fields interact.

You'll find I am correct on the issue. Now move along.

5. ### TrappedBannedBanned

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Aside from Aqueous and his attempts to understand field theory, there are real reasons why we cannot understand point like particles as a real artifact of nature. If you do an integral on the classical radius with limit $R \rightarrow 0$ then you find a point like particle has a singularity.

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8. ### TrappedBannedBanned

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Oh my lord... lol

Listen to me, fields interact. This terminology is as old as quantum field theory itself. Whatever it is you are trying to argue, smells of semantic bullshit.

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10. ### TrappedBannedBanned

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And the point?

I said, that only fields interact ... matter, most consisting of pointlike particles never interact with each other. Only their fields do. Whether you multiply those fields, add them... any other mathematical process which might couple two fields together, are irrelevant.

11. ### Aqueous Idflat Earth skepticValued Senior Member

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The point is that fields/waves add. Therefore they can not interact.

12. ### TrappedBannedBanned

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That's not true. You are working on a limited knowledge of how fields interact. What you are saying is probably true in some interference patterns of how some wave dynamics occur... There are in fact many cases in which fields interact mathematically-speaking. Waves as far as I know occur mathematically speaking are added only when there is a superposition involved. How this ambiguity we are having about how fields interact I am not sure we are going to settle.

I forget now the equation that described the fields interaction term. I know one exists however (in fact quite a few exist, I know some of them). What you are showing me are elementary diagrams of some basics of wave dynamics, when I am talking about a deep understanding of quantum field theory... or one I had when talking about the subject. The subject of fields only interacting was written about extensively by Schwinger and have since no longer this paper.

But it is generally known among good physicists that point particles don't interact, only their fields do. We argue this until the sun goes down, which is why I am not going to argue it any more. If you are not willing to listen to me, so be it.

13. ### Declan LunnyRegistered Senior Member

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I'm thinking it might be you who is arguing semantics. I would suggest that a particle and it's associated field are one thing. One can not be independent of the other. Particle "A"'s field does not interact with particle "B"'s field, it interacts with particle "B". And the reverse is also true.

It seems like you are saying that Declan didn't pick up his coffee mug, Declan's hand picked it up. If you separate my hand from me, neither Declan nor his hand can interact with the coffee mug.

Can you separate a particle and it's field into two independent entities? It seems to me if you separate a particle and it's field from each other then and only then will you create a paradox. Particles do interact with each other. Saying they do not is semantics based on an unphysical false paradox.

14. ### TrappedBannedBanned

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Particles and fields are the same thing... yes. I don't dispute this.

But... the picture being presented is that you have a classical interaction, where two pointlike particles physically scatter. This isn't true. As I wrote about above, it's been known by physicists for a while that pointlike particles don't even interact with each other.

Now.... you can say they do if they act like waves. This is the wave particle duality that can cause this disruption in the conversation. The particle is a particle when there is an interaction. But the interaction is never made directly between two point particles. What happens is that the wave function collapses and the electron ''appears'' in a place statistically speaking, relative to say a passing positron moving in the opposite direction. Their fields may interact in such a way to create a Cooper Pair, for a quick example.

15. ### TrappedBannedBanned

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Well... Positronium is the correct name for that particle sorry. Cooper pair is any two bound electron states.

16. ### Declan LunnyRegistered Senior Member

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That is semantics,,,,,, Saying the "fields" interact to deny that the "particles" interact does not imply a paradox. It is just as true to say that the "particles" interact to deny that the "fields" interact. The particle can not exist independently of it's field. The field can not exist independent of it's particle. The only paradox is the semantics in trying to imply that fields and particles are some separate things. They are not, so there is no paradox only a false implication of conditions of the terms used to describe it.

17. ### TrappedBannedBanned

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It may appear like a paradox, but reminds me of Schrodingers Cat. All these so-called ''paradoxes'' have logical answers. The particle is never a particle and a wave at the same time. Whether it behaves as a wave or a particle depends on it's environment. If the wave of a ''system'' (to replace the word particle), then that system exhibits ''point like interaction.'' As noted in the OP, this is a misnomer, point particles don't interact directly, their fields interact. Yes... fields consist of particles and particles generate fields, you cannot separate the two, but as far as how they behave at a given time, they simply cannot be both states at the time.

18. ### Declan LunnyRegistered Senior Member

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It's possible I may be mistaken, but it seems to me that you might conflating particles, waves, fields, and wavefunctions. It is necessary to be very careful when discussing these items in the same conversation, because it is very easy get off point if they are misapplied.

19. ### Aqueous Idflat Earth skepticValued Senior Member

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Since that's everywhere it's not a limiting case.

You forgot more important ideas, beginning with how to detect your own errors.
Fields cannot interact or they would not be observed simply adding.

Forget that. Just state the principle. But it has to be correct, or posters will debunk it.

What I demonstrated was examples of waves adding. You are and/or were in denial of that.

Before you can have a deep understanding of something you must first be able to tread the shallow waters.

Before you can hope to follow Schwinger's ideas you need to tackle first principles.

Physicists are presumed innocent of whatever you think of them, by virtue of passing the requisite exams. Until you can do the same, you have no legitimate reason to deem any physicist "good" or "bad". Agreeing with you is not the test. The tests are the test.

"Point" particles is meaningless. No one knows why you are inserting the word "point". Particles are quantum-scale objects of various classes and properties. "Interaction" involves energy exchange. It's pointless to argue that waves exchange energy, just as it's futile to deny superposition. It's also futile to argue ideas about particle physics without establishing facts predicated in first principles and the universal speech used to convey scientific ideas clearly. Thus, "quantum particle" is sufficient to convey to us that you are speaking of the same particles actual particle physicists speak of.

Since I have been the main person listening to you and giving you clues to fix your mistakes, you're wrong about who is ignoring whom.
The simplest way to advance yourself is to correct yourself: learn the principle at issue and move on. Otherwise, yes, you will be stuck in that same rut indefinitely.

20. ### Declan LunnyRegistered Senior Member

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I wish you would repeat that with great big bold font text (I can't seem to get an editor to work on this site.)

Far too many of the "causal" (popular press taught) physicists you run into on the internet don't even know what 1st principles means, much less have done the work to learn them. My pet-peeve with the internet "theorists" is that they always take umbrage when you point out to them that their grand new physical insight is not supported by 1st principles. They usually rely on citing a name as authority rather than the work that the name produced,

For example,,,,,, On another forum a poster kept, ad nauseum, telling me: "God does not play dice" as proof of his "theory", and that Einstein said it so it must be true. He insisted that it should be accepted as one of my cherished 1st principles and defended it by "So you think you know more than Einstein?". His other annoying self-validating trait was, "I've read Brian Greene's book three times so I'm sure I understand it as well you (I've had 8 years of undergrad and graduate study.)"

First Principles Must Come First. (And they really aren't that hard to learn.) Then tackle the good "wow" stuff.

21. ### TrappedBannedBanned

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Neither of you have a clue what you are talking about.

What I am talking about, are first principles. I know all this knowledge because I read original field equations that have been fully described by a number of physicists. Particles don't interact, only their fields do. I am not talking about this any more, the both of you can be wrong and not listen to me.

22. ### Declan LunnyRegistered Senior Member

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No, I DO have a clue of what I'm talking about, because it's me talking about what I'm talking about. You might not have a clue about what I'm talking about. I might not have a clue about what you are talking about, but I am sure you know what you are talking about.

That works for me. My feelings won't be hurt.

23. ### UndefinedBannedBanned

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1,695
Hi Trapped, Aqueous, Declan, everyone.

To help avoid more cross-purpose exchanges and confusions, it may be worth it if you all discuss the subtle variations of scattering outcomes before any further generalized statements about what fields actually involve and what they do when they meet in various circumstances and configurations Ie, plane waves, spherical and glancing etc).

For example, while the simplistic view of adding/subtracting waves is fine for when the plane waves meet and either construct/deconstruct and the resultant products remain essentially in the same line, ie, when resultant wave(s) (and/or the respective mutually-negated field-perturbations of the incoming waves revert-back-to-underlying-field-states) do not actually 'exit/negate' in any other direction than the line of motion that the incoming waves were following (this is the simplistic case as depicted by your gifs, Aqueous).

The more 'glancing', polarized and spherically 'messy' meetings between field perturbation features that involve opposing quantum mechanical SPIN orientations and other MUTUALLY REPELLING and mutually DISTORTING properties/effects on each other as the 'parent particle/wave features' configurations and dynamical effects intermingle as they attract/repel in non-simplistic dynamical ways, then the angles and the polarity and the spins and the energy exchanges/flows that occur may MODIFY BOTH the interacting features (ie, the particle-waves' central core configurations AND their peripheral extended-field effect/influences/energy DYNAMIC QUANTA content/configuration/distribution etc).

So, the outcomes and interaction types depend deeply/complexly on what level and kind of 'meeting' and what kind(s) of 'particle-wave field-perturbation feature(s)' one includes in the context of what point they are trying to elucidate by use of such field behavior examples/references.

Good luck, and enjoy your further discussion, guys!