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2022-12-08: How Are Quasiparticles Different From Particles?

  • 08:40: ... forming a nucleus and electrons bound to that nucleus by the exchange of virtual photons. ...

2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics?

  • 06:02: ... probability at each vertex, each interaction between electron  and virtual photon, adjusted by all these other parameters I ...

2022-08-24: What Makes The Strong Force Strong?

  • 06:07: We can think of each charged particle as generating a constant buzz of virtual photons around it, forming what we think of as its EM field.

2022-01-27: How Does Gravity Escape A Black Hole?

  • 06:16: ... force is communicated between charged particles by transferring virtual photons - ephemeral excitations in the electromagnetic ...
  • 07:08: They interact by exchanging a virtual photon.
  • 07:10: Or more precisely, they exchange the sum of all possible virtual photons.

2021-12-10: 2021 End of Year AMA!

  • 00:02: ... where the electron and the proton are moving together and a little virtual photon wiggles between them causing the particles to be drawn together or in ...

2021-04-07: Why the Muon g-2 Results Are So Exciting!

  • 04:33: In this theory, electromagnetic interactions result from charge particles communicating by exchanging virtual photons.
  • 04:47: For example, a pair of electrons could repel each other by exchanging one virtual photon, or two virtual photons, or three et cetera.
  • 04:56: All those virtual photons could do something weird like momentarily becoming an electron-positron pair.
  • 05:48: ... next simplest is for the electron to emit a virtual photon just prior to absorbing the magnetic field photon, and then reabsorbing ...

2020-02-03: Are there Infinite Versions of You?

  • 15:00: Imagine an interaction where an electron emits a virtual photon which then deflects another particles - say, a proton.
  • 15:08: ... direction of the flow of time is irrelevant from the perspective of the virtual photon - what matters is the structure of the ...

2018-10-31: Are Virtual Particles A New Layer of Reality?

  • 03:25: ... one photon worth of quantum properties in a single packet that we call a virtual photon. ...
  • 06:00: One electron throws a virtual photon at the other one causing them to be deflected from each other like a game of quantum dodgeball.
  • 06:17: Let's look at the fine and diagram of a single virtual photon passing from electron to positron.
  • 06:23: ... effect of this, you add together the possible effect of every possible virtual photon being emitted by the electron and absorbed by the ...
  • 06:50: These are the virtual photons that ultimately provide the attractive force.
  • 07:53: Our virtual photon doesn't have a location, so it doesn't travel a real path.
  • 08:16: No individual virtual photon can be credited with producing the attractive force.
  • 08:22: In fact, you only see that force in the sum of all possible virtual photons over all possible Feynman diagrams.

2018-08-15: Quantum Theory's Most Incredible Prediction

  • 07:22: So one way to think about this quantum buzz is with virtual photons.
  • 07:36: In the case of electromagnetism, those interactions are mediated by virtual photons, which are just a mathematical way to describe quantum buzz.
  • 07:45: Every interaction with virtual photons that can happen, does, at least in a sense.
  • 08:17: They represent the possible interactions of the quantum field by way of virtual photons.
  • 08:47: The electron first emits a virtual photon, then gets deflected, then re-absorbs the virtual photon.

2018-06-20: The Black Hole Information Paradox

  • 14:01: But quantum-field theory imagines the electromagnetic force as being transmitted by virtual photons.
  • 14:07: Now it's important to note the distinction between virtual photons and real photons.

2017-11-29: Citizen Science + Zero-Point Challenge Answer

  • 06:57: ... of the vacuum energy density comes from assuming that there are no virtual photons above a certain cut of ...
  • 08:32: ... it tells us that the simplistic approach of choosing the right maximum virtual photon frequency definitely can't give us the vacuum energy that we see as dark ...
  • 08:42: ... interactions that require the exchange of much shorter wavelength virtual photons. ...
  • 09:06: That proves the existence of virtual photons with wavelengths smaller than the plate separation.

2017-11-08: Zero-Point Energy Demystified

  • 09:09: And is this a possible maximum virtual photon frequency, given the results of Casimir experiments?

2017-11-02: The Vacuum Catastrophe

  • 02:55: What if there's a maximum possible frequency for virtual photons?
  • 03:31: ... if we add up the vacuum energy, including virtual photons, all the way up to the Planck energy, we get a finite number-- a very, ...

2017-10-19: The Nature of Nothing

  • 04:33: For example, QFT describes the electromagnetic force as the exchange of virtual photons between charged particles.
  • 05:55: And so virtual photons can exist for any amount of time, long enough to carry the electromagnetic force to any distance.
  • 08:43: He imagined two conducting plates, brought so close together that only certain virtual photons could exist between the plates.
  • 08:51: ... only resonates with waves of certain frequencies, any non-resonant virtual photon would be excluded, reducing the vacuum energy between the ...
  • 09:05: However, on the outer surface of the plates, all frequencies of virtual photon are allowed.

2017-08-10: The One-Electron Universe

  • 09:44: ... and an electron influencing each other's momentum by exchanging a virtual photon-- similar to electron-electron ...
  • 09:53: ... the electron and positron actually annihilate each other, producing a virtual photon, which then creates a new electron-positron ...

2017-07-26: The Secrets of Feynman Diagrams

  • 10:41: The most important Feynman diagrams for Bhabha scattering are the two cases involving a single virtual photon.

2017-07-12: Solving the Impossible in Quantum Field Theory

  • 02:49: In fact, we call it a virtual photon, and it only exists long enough to communicate this force.
  • 03:31: They exchange a virtual photon-- this squiggly line here-- and the two electrons move apart at the end.
  • 04:09: ... all of the ways that two electrons can deflect involving only a single virtual photon. ...
  • 05:26: For example, the electrons might exchange just a single virtual photon, but they might also exchange two, or three, or more.
  • 05:34: The electrons might also emit and reabsorb a virtual photon.
  • 07:43: ... include exchanging two virtual photons, or one electron emitting and reabsorbing a virtual photon, or the ...
  • 08:41: Electrons are constantly interacting with virtual photons.
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