B Energy loss in the beam of LHC

[phoenix95]

TL;DR Summary

Could the beam lose energy purely because of the quantum mechanical nature of vacuum?

Generally, one would expect the beam to lose its content (energy or particles) if it hits anything before its reaching its target. The whole idea of maintaining (conventional) vacuum using pumps or other means is to minimize that loss. But is it possible that there could be a beam loss purely because of a quantum mechanical vacuum? That is because the uncertainty principle guarantees that no space is completely empty and so there would be inevitable and unavoidable beam loss?

 

[mfb]

The beam has zero kinetic energy in the reference frame of the beam. Where would the energy come from to change that, and in which direction would the particles accelerate?

That is because the uncertainty principle guarantees that no space is completely empty

It doesn't.

 

[Vanadium 50]

That is because the uncertainty principle guarantees that no space is completely empty

Huh? What? I don't understand what this means.

 

[phoenix95]

That is because the uncertainty principle guarantees that no space is completely empty

Isn't it true that there would always be quantum fluctuations? Virtual particles-antiparticle pairs being created and annihilated, or was I wrong when I assumed (at least implicitly) that "the beam can interact with the quantum fluctuations/virtual particles"?

I think my main confusion here is whether or not the beam (or any matter particle) can interact with virtual particles.

 

[mfb]

Virtual particles-antiparticle pairs being created and annihilated

There is no such process, no matter how often popular science descriptions repeat that myth.

Virtual particles are tools in some calculations. They are as real as an integral sign. Particle beams don't interact with integral signs either.

 

[artis]

I think @phoenix95 was thinking the vacuum energy aka zero point energy that is theorized and predicted to exist throughout space even under complete vacuum. The particles he was talking about are probably the particles said to spontaneously be created due to the underlying vacuum field.
So if I can and if that makes any sense I could rephrase his original question into " how would the passing of a 0.99c proton beam through the Casimir plates affect the outcome of the Casimir plate experiment if one was able to pass such a proton beam through the narrow opening between such plates"

 

[mfb]

It would have nothing to do with the Casimir effect, but the proton bunches come with a strong electromagnetic field, which would interact with following bunches - most likely leading to an emergency beam dump. It would also lead to forces on the plates far stronger than the Casimir effect.

 

[Vanadium 50]

It is a bad idea to speculate about what the OP "really means", which I will now demonstrate. It's better to ask and let them answer.

"the passing of a 0.99c proton beam through the Casimir plates"

Obviously when the beam hits through the plates there will be a spray of secondary particles when it hits them. Thick enough and the beam will stop in tehm.

"No, no! Not through that way! Through the other way! Between them!"

Casimir plates are conductors. The beam is a current. The beam will generate an image current on the plates. The magnetic forces from the image current will affect the beam - coupling the head of the beam to the tail of the beam. This causes an instability.

"No. no! This is ordinary! I want Casimir magic! Vacuum voodoo! Beam bippity boppity boo!"

<sigh>

 

[vanhees71]

I think quantum theory is exciting enough without all the voodoo many popular-science books claim just to be sold. Already the Casimir effect has nothing to do with a "pure vacuum" but it's about (quantum) fluctuations of the charges making up the plates. Having a proton beam as delivered from the LHC between the plates you are very far from having vacuum at all and fortunately the protons in the accelerator can be described by classical electrodynamics and (relativistic) mechanics. No "quantum voodoo" needed ;-).

 

[phoenix95]

My apologies for replying late. I forgot about the thread after that answer from @mfb which I thought was good enough. Let me just make some remarks.

Sometimes when I have a question, it is not obligated to receive an answer by any means; it could very well be possible that the question was framed on the basis of a misconception, and asking that question nonetheless would help clear out that misconception. This is exactly what happened in #4 and#5. In all honesty, you did not have to reply to a senseless question (one could say that is the purpose of the platform, but given that I was talking about LHC beams and the quantum vacuum should hint at least some background in physics; which means I should have paid attention to my homework, which would have stopped that misconception in its tracks) but you did, and I thank you for that.

What @artis mentioned in #6 was exactly what I meant when I said quantum vacuum in #1. But as I said, the answer by @mfb in #5 cleared it out.

Now let me address this:

If

It is a bad idea to speculate about what the OP "really means", which I will now demonstrate.

then why are speculating that OP and/or other poster meant

"No. no! This is ordinary! I want Casimir magic! Vacuum voodoo! Beam bippity boppity boo!"

<sigh>

? To put it in a sentence: Why would you assume that the person is only asking that question for the sake/interest of "quantum voodoo"?

I think quantum theory is exciting enough without all the voodoo many popular-science books claim just to be sold.

Yes, of course. Maybe that is probably why the OP is interested in LHC beams and not 'goop lab von Netflix'.

I'm sorry if this post seems a bit aggressive. I understand the fault was in my own misconception as well as the wording of the thread; I didn't mean to offend any of the mentors/advisors above. It is contradictory when the academia around me boasts "Ask questions. There are no stupid questions only stupid answers (and other inspirational quotes that are too much to fit in this quotation)". And when I do then I hear "Oh that is a stupid question. Well, you should have done your homework. Where do get these? From Quantum voodoo?". In the post I wrote above, I had two concepts that I had known: vacuum/virtual particles and LHC beams. I was merely asking how the two reconciled with each other. And for that same matter

"the passing of a 0.99c proton beam through the Casimir plates"

is just another student trying to reconcile their own understandings of two different things. I might have very well asked, "What would be the energy of the LHC beam that is required such that firing it through a dripping faucet would stop the dripping, after considering gravity and friction". Sure, it is a dumb question. But not necessarily as bad as the need to <sigh>.

I know all of you mentors. Either directly or indirectly, you have helped me on this platform many times before. Knowing your expertise, it would be impudent of me to say that your approach is wrong. I just hope that the atmosphere here remains the same for other students (and for me; to be honest it's just for me, I added the phrase 'other students' to seem polite and empathizing) to come. Please don't brush off any questions as 'unworthy'.