Photon as composite of electron and positron

K S Mallesh
Messages
4
Reaction score
0
A photon annihilates into an electron and a positron (both having spin 1/2). The reverse process is also a reality. Can the photon therefore be viewed as a composite of an electron and a positron having a total spin 1?
 
Physics news on Phys.org
K S Mallesh said:
A photon annihilates into an electron and a positron (both having spin 1/2). The reverse process is also a reality. Can the photon therefore be viewed as a composite of an electron and a positron having a total spin 1?

I once thought this until I discovered that pair production by the photon can also yield other particles.

http://arxiv.org/abs/astro-ph/0111460
V. A. Kudryavtsev
(Submitted on 23 Nov 2001)

Abstract: Production of muon pairs by high-energy photons in electromagnetic and hadronic showers in atmosphere has been calculated.

But I wouldn't be discouraged by what I say. A day doesn't go by that someone here at the forum doesn't ask a question about photon's. I have the feeling that no one is even close to understanding light.
 
A bound state of electron and positron is well-known in nature and it is not stable as it will decay in two photons in 125 picoseconds for the singlet case. This is called positronium. So, photons should be regarded as truly elementary particles unless a more fundamental theory is found with other building blocks.

Anyway you can see this by yourself as electrons and positrons can have only weak and electromagnetic interactions and while the former cannot form bound states due to their extreme weakness, the latter forms bound states but with bound energy of the order of eV making the bonding not that strong. Besides, due to quantum electrodynamics, this bound is not even stable. You should note here a difference with respect to atoms.

Jon
 
Lester said:
A bound state of electron and positron is well-known in nature and it is not stable as it will decay in two photons in 125 picoseconds for the singlet case. This is called positronium. So, photons should be regarded as truly elementary particles unless a more fundamental theory is found with other building blocks.

Anyway you can see this by yourself as electrons and positrons can have only weak and electromagnetic interactions and while the former cannot form bound states due to their extreme weakness, the latter forms bound states but with bound energy of the order of eV making the bonding not that strong. Besides, due to quantum electrodynamics, this bound is not even stable. You should note here a difference with respect to atoms.

Jon

Dear Sir,
Thanks for your reply which contains reasonable aspects that do not favour such composite nature for photons
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
According to recent podcast between Jacob Barandes and Sean Carroll, Barandes claims that putting a sensitive qubit near one of the slits of a double slit interference experiment is sufficient to break the interference pattern. Here are his words from the official transcript: Is that true? Caveats I see: The qubit is a quantum object, so if the particle was in a superposition of up and down, the qubit can be in a superposition too. Measuring the qubit in an orthogonal direction might...

Similar threads

Back
Top