Ghostly Interactions: Real World Effects?

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Discussion Overview

The discussion revolves around the concept of zero point energy (ZPE) and its potential effects on real-world particles and structures. Participants explore the implications of ZPE in quantum mechanics, particularly in relation to harmonic oscillators and virtual particles.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants inquire about the effects of ghostly zero point energy on real-world particles, expressing a desire for basic explanations.
  • One participant explains that the zero point energy of a harmonic oscillator is non-zero due to the Heisenberg uncertainty principle, and discusses the energy contributions from multiple oscillators in a crystalline lattice.
  • Another participant introduces the concept of a particle in a box to illustrate why the lowest energy value must be non-zero, linking it to the uncertainty principle.
  • Some participants propose that the ZPE field affects all baryonic structures and cannot be separated from perceived physical structure.
  • There is mention of virtual particles and their relationship to real interactions, with references to observable phenomena like the Casimir effect as manifestations of vacuum energy fluctuations.
  • Questions arise regarding the nature of virtual particles and their compliance with Einstein's energy relation, with discussions on how they differ from real particles.
  • One participant notes that virtual particles, as exchange particles, take energy from uncertainty and thus do not obey the energy relation for the duration of their existence.

Areas of Agreement / Disagreement

Participants express varying degrees of understanding and interpretation regarding the implications of zero point energy and virtual particles. There is no consensus on the effects of ZPE or the nature of virtual particles, indicating multiple competing views remain.

Contextual Notes

Some discussions reference specific quantum mechanics concepts and equations, but there are unresolved questions about the definitions and implications of virtual particles and their interactions.

wolram
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Please excuse an ignorant question, but does this ghostly zero point
energy have any effect on real world particles?
 
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wolram said:
Please excuse an ignorant question, but does this ghostly zero point
energy have any effect on real world particles?

what is gostly about the zero point energy ?

marlon
 
I don't know i am hoping that someone can give me an insight of these
interactions.
 
A cristall latter in its ground state can be explained with the harmonic oscillator. The zero point energy of such an oscillator isn't zero like in classical mechanics. Thus, the zpe of a harmonic oscillator of for example a atomic latter is:

E=h(bar)w/2.

Now, of course there are a lot of oscillators in such a latter and the whole energy of a cristallic latter in ground state is:
E=E(oscillator 1)+E(oscillator 2)+...+E(oscillator n). (the oscillators 1 to n are all in ground state and can have diverent numbers of w).

The ground state energy of a harmonic oscillator isn't zero cause of the Heisenberg's uncertainty principle.
 
Please be kind to me, i am asking this question as a pedestrian, if
you can give a basic answer, something that is understander able
to the GP i will be in your debt
 
wolram said:
Please be kind to me, i am asking this question as a pedestrian, if
you can give a basic answer, something that is understander able
to the GP i will be in your debt

Look at the particle in a box (a potential well from which it "may" not escape)

In the box the potential is zero, at the exterior the potential is infinite

If the lowest energy value were zero then we know that the momentum is zero (E = p²/2m + 0). But the due to [tex]\Delta x \Delta p = constant[/tex] the position (x) is infinite and the particle is no longer in the box because it has no specific position... You see ? Thus, the lowest energy value must be non-zero

marlon
 
So the ZPE field has an effect on all "baryonic", structures, and can
not be divorced from perceived physical structure?
 
wolram said:
So the ZPE field has an effect on all "baryonic", structures, and can
not be divorced from perceived physical structure?

Virtual particles cannot be seen since they are not "physical"
I mean, they are not on mass shell or they don't obey the Einstein energy relationship. However their effect on "real" interactions is definitely there.

As to the ZPE, the Casimir effect is a pure and observable manifestation of this virtual particle see that arises due to vacuum energy fluctuations. Check Wikipedia for that matter

marlon
 
@marlon:
mass shell: obey Einstein's energy relation
mass shell: do not obey Einstein's energy relation

You mean this equation: E^2=(cp)^2+(mc^2)^2
So a real particle does obey this equation, because it has a given momentum and mass. But why don't virtual particle (take a positron) obey this equation?
I mean they have mass, they have momentum?
 
  • #10
Sterj said:
@marlon:
mass shell: obey Einstein's energy relation
mass shell: do not obey Einstein's energy relation
indeed

You mean this equation: E^2=(cp)^2+(mc^2)^2
So a real particle does obey this equation, because it has a given momentum and mass.

Indeed

But why don't virtual particle (take a positron) obey this equation?
I mean they have mass, they have momentum?

Because such a virtual particle is an intermediate stage of an interaction between real particles. QFT teaches us that we need to integrate over all momentum-values of such particles.

marlon
 
  • #11
yes, but if we work in vacuum for example a virtual photon can create a positron-electron pair. Is it right, that in this case the electron-positron pait can not be observed?

If the virtual particle is only an exchange particle, it takes its energy from uncertainty and this particle will disappear after a short while, so the einstein's energy relation isn't obeyed, because this was only there for a short while.

(sorry for such an English)
 
  • #12
Sterj,
i have answered these matters in the QM-section, more specifically in the virtual particles thread

marlon
 

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