The One Electron Universe suggested by Wheeler

[Parthib Roy]

The one-electron universe is the hypothesis that all electrons and positrons are actually manifestations of a single entity moving backwards and forwards in time. It was proposed by theoretical physicist John Wheeler in a telephone call to Richard Feynman in the spring of 1940.
The idea is based on the world lines traced out across spacetime by every electron. Rather than have myriad such lines, Wheeler suggested that they could all be parts of one single line like a huge tangled knot, traced out by the one electron. Any given moment in time is represented by a slice across spacetime, and would meet the knotted line a great many times. Each such meeting point represents a real electron at that moment.

At those points, half the lines will be directed forward in time and half will have looped round and be directed backwards. Wheeler suggested that these backwards sections appeared as the antiparticle to the electron, the positron.

My Question is that the reasoning given by Feynman that many more electrons have been observed than positrons, and electrons are thought to comfortably outnumber them, seems insufficient to me for rejecting a beautiful hypothesis like this as evidently Feynman arrived at a defining conclution that antiparticles could be represented by reversed world lines, and credits this to Wheeler, saying in his Nobel speech - "I took the observation that positrons could simply be represented as electrons going from the future to the past in a back section of their world lines. That, I stole!" shown enough result that Wheelers hypothesis wasn't vague or random at all! So why wasn't any attempts made in reconsidering his predictions? And how does the fundamental nature of electrons change when they travel backwards in time ?

sources - https://en.wikipedia.org/wiki/One-electron_universe
https://kids.kiddle.co/Pocono_Conference

Thank you,
Parthib Roy

 

[PeterDonis]

as evidently Feynman arrived at a defining conclution that antiparticles could be represented by reversed world lines, and credits this to Wheeler

That's true, but that hypothesis is not the same as Wheeler's "one electron" hypothesis.

In quantum field theory--or more precisely, when doing perturbation theory in QFT--we do represent antiparticles as lines in Feynman diagrams with their arrows "going the other way", so to speak. So that is no longer a hypothesis, it's part of how we do QFT. (Note that there are limitations to this point of view, which is why I specified that it's used when doing perturbation theory.)

Wheeler's "one electron" hypothesis, however, remains just a hypothesis, with the obvious argument against it that Feynman gave, which you describe. But that is only an argument against the "one electron" hypothesis; it is not an argument against the more general claim that we can describe antiparticles, under suitable conditions, as particles with their lines "going the other way".

 

[Parthib Roy]

Wheeler's "one electron" hypothesis, however, remains just a hypothesis, with the obvious argument against it that Feynman gave, which you describe.

Was availability of more electrons than positrons the only argument against wheelers one electron hypothesis ?
And are electrons truly identical to each other except their spin quantum number ?

And how does the fundamental nature of electrons change when they travel backwards in time ?

And could u write a seperate tread answering this question ...

The idea is based on the world lines traced out across spacetime by every electron. Rather than have myriad such lines, Wheeler suggested that they could all be parts of one single line like a huge tangled knot, traced out by the one electron. Any given moment in time is represented by a slice across spacetime, and would meet the knotted line a great many times. Each such meeting point represents a real electron at that moment.

Also was there any substance to the thought of world lines being represented as knots in Wheelers explaination?

 

[PeterDonis]

Was availability of more electrons than positrons the only argument against wheelers one electron hypothesis ?

No. I don't think the hypothesis was intended as a serious scientific theoretical hypothesis; it was a typical whimsical suggestion of Wheeler's.

the thought of world lines being represented as knots

I don't know that that was even part of Wheeler's hypothesis; the word "knots" was yours, not Wheeler's.

 

[PeterDonis]

are electrons truly identical to each other except their spin quantum number ?

This question isn't a question of physics, because "truly identical" is vague ordinary language. If I have one electron with spin up in a box over here and another with spin down in a box over there, they differ in more than just their spin quantum number. Are they still "truly identical"?

The physics, according to our best current theories, is that there is a quantum field, the electron field (one of the fields in the Standard Model), and every "particle" that we call an "electron" is an excitation of the same quantum field, just at different points of spacetime.

 

[PeroK]

And are electrons truly identical?

If you owned an electron, what do you propose doing to it so that anyone who finds it knows that it's your electron. You can't stamp a serial number or your name and address on it.