Where do photon gets its electric field without carrying charge?

Question

Electric field is determined by the electric force per unit charge, but photon clearly doesn't carry charge so where do the electric field came from?

Answer 1

Photons don't generate electric field. Photons are electric field, or more precisely electromagnetic field.

In classical physics we tend to describe quantities in terms of fields, which are entities that span over the whole spatial dimensions and contain information at each point in space. You gave the example of the electric field, which contains the information about the electric force on sample charge at each point.

In quantum physics, or more specifically in Quantum Field Theory, we usually describe quantum fields as collections of particles. The procedure that takes a classical field and tells us how to deacribe it in terms of field particles is known as Second Quantization. In the case of electromagnetism the theory is called Quantum Electrodynamics (or QED for short). It tells us that the electromagnetic field itself is composed, in fact, of excitations of particles named photons. In other words, a photon is an excitation of a specific state of the electromagnetic field.

Answer 2

It is not necessary to have a charge in order to generate an electric field. One relevant Maxwell's equation includes the curl of E related to dB/dt, and another adds a term to electric current called the 'displacement current' that generates a magnetic field (B) from a nonconstant electric field (D), even if there is no current of charges in motion.

So, a photon is created in a light bulb by charges (electrons) in thermal motion, but once it starts propogating it leaves that behind. The photon needs carry no charge in order to travel (indeed, it travels faster in a vacuum than any charged particle).

Historically, the notion that some material supported the wave motion was rejected by Einstein on philosophical grounds, and found inconsistent with results of the Michaelson-Morley experiments of 1887. Those were very important steps in early 'modern physics'.

Answer 3

There is not any displacement of current as you have said it here There is only oscillations of free electrons in conductors when an electric field is applied, and its repulsive force by negatively charged terminal where electrons have been accumulated push the immediate electrons in the directly connected conductor, while these free electrons are in their radom motions. However the ekectric repulsive force only shift the random motions of free electrons a little bit in the opposite direction to that of the electric field across the circuit, which is from positive terminal of the electric source, such as a power plant or or a transformer station where tge potential voltage from the powed plant is decreased to to appropriate lower potential voltages for different uses. Such a shift of a free electron's random motion in conductors is called as its drift speed which is very slow, about 10^-5 m/s while its random speed in all directions is about 10^6m/s. But there are a lot of free electrons within a fixed volome of a conductor, and when the first immediate electrons are repelled by the repulsive force of accumulated electrons on the negatively charged terminal , the electrons's random motions are shift a little bit toward their adjacent neighbouring free electrons, and repels the adjacent electron's random motions , then those repelled electrons repel next electrons' to them, and the repulsive force is continously transmitted across the circuit from electrons to electrons which are already available in conductors, that's why whenever you turn a light bulb on, thermal energy in the filament radiates instantly with coming photons or light. Additionally since the current is an AC one , the direction of the free electrons' random motions' are shiftted back and forth about their positions of random motions which establishes the current in the curcuit, and is accurately defined as free electrons' oscillations , but there is not any sort of transport of mass or electrons from one end of the circuit to its another end as the way how you have fundamentally misunderstood it
About whether phtons have any mass or not, neither classical physics nor quantum mechanics or physics has ever been able to answer the question why photons can establish an electric field , thus a magnetic field to be assumed as electromagnetic fields as mr Maxell's illogical theories, and Einstein's nonsensical assumption on

No form of matter in the universe can exist without accupying any space at all no matter whether it isalways in motion or stationary or sometimes in motion , other times static. It means that any form of matter either observable to human extremely limited knowledge or unobservable at all or unknowable unknown has to have a mass to occupy some point or volume space to be able to interract with other forms of matter seen in such natural phenomena as sunlight, moonlight, human--invented artificial light