# I Waveform of virtual photons

1. Feb 10, 2017

### Jeff Root

My understanding is that the wavelength or frequency of an
individual photon cannot be reliably measured. For example,
if a beam of monochromatic light is filtered so that only one
photon at a time enters a spectroscope, each photon may land
anywhere on the screen. Only when a statistically large number
of photons have hit the screen does it become apparent that
they form a bright line in a specific position, with individual
hits having something similar to a Gaussian distribution.

The fact that the pattern emerges from observing the hits of
numerous individual photons shows that each individual photon
does have the same specific wavelength and frequency.

Also, detection of a photon is all or nothing. A photon is
either detected or not. The entire photon must reach any
detector in order for it to be detected, and then all you can
know is where and when the photon hit, and roughly how much
energy it had relative to the detector, again with something
like a Gaussian distribution. That means the waveform of an
individual photon cannot be observed at all.

The electric force is carried by virtual photons.

Positive charges continuously "emit" virtual photons which
repel other positive charges and attract negative charges.

Negative charges continuously "emit" virtual photons which
repel other negative charges and attract positive charges.

There must be a difference between these two types of virtual
photons. Could it be a difference in their waveforms?

For example, might virtual photons emitted by positive
charges have an electric field which first goes positive,
then negative, while virtual photons emitted by negative
charges have an electric field which first goes negative,
then positive?

Such as the two configurations on the left in this diagram:

http://www.freemars.org/jeff/misc/cosmolog/4photons.png

-- Jeff, in Minneapolis

2. Feb 10, 2017

### Staff: Mentor

As I understand it, virtual photons do not exist except in the math. They have no electric (or magnetic) field and don't behave like real photons (which have alternating electric and magnetic fields associated with them). They have no 'waveform' or wavefunction. They don't even move through space.

3. Feb 10, 2017

### m k

Before you continue consider this.

The highest peak of those individual photons are not in front of those slits.

4. Feb 10, 2017

### Staff: Mentor

This is not how virtual particles convey forces.
As an explanation suitable for an I-level thread, you might try http://math.ucr.edu/home/baez/physics/Quantum/virtual_particles.html. (However, do note that Baez uses phrases like "monstrous oversimplification" with some frequency in that piece - a proper explanation requires a proper textbook on quantum electrodynamics, but that's not going to work in an I-level thread).

The documents linked from the first two posts of https://www.physicsforums.com/threads/what-is-a-photon.879128/ are also good references for photons in general, as is Feynman's math-free and layman friendly book "QED: The strange theory of light and matter".

As this thread is based on several misunderstandings (and is close to violating the Physics Forums rule about personal theories) it is closed. As with all such closures, PM me or any other mentor if you would like to add something to it that will help the next person reading it better understand the physics here.

5. Feb 10, 2017

### Staff: Mentor

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