# [ELI5] How do photons mediates the electromagnetic force?

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[ELI5] How do photons mediates the electromagnetic force?

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Photons are packets of energy in the electromagnetic field. That energy will impart momentum to particles that absorb them. And, particles will lose momentum when they emit a photon. Also important is that for the purposes of particles bouncing around, a photon can have “negative” momentum.

So, two electrons come close to each other. One of them spits out a photon and as a result, loses that momentum, causing it to go off in a direction. The other electron absorbs the photon and gains that momentum, causing it to fly off in the other direction. As a result, the electrons repel each other.

Something similar happens when, say, an electron and proton come close, except that the momentum is “negative” so the electron and proton end up flying towards each other.

Photons are packets of energy in the electromagnetic field. That energy will impart momentum to particles that absorb them. And, particles will lose momentum when they emit a photon. Also important is that for the purposes of particles bouncing around, a photon can have “negative” momentum.

So, two electrons come close to each other. One of them spits out a photon and as a result, loses that momentum, causing it to go off in a direction. The other electron absorbs the photon and gains that momentum, causing it to fly off in the other direction. As a result, the electrons repel each other.

Something similar happens when, say, an electron and proton come close, except that the momentum is “negative” so the electron and proton end up flying towards each other.

Photons are packets of energy in the electromagnetic field. That energy will impart momentum to particles that absorb them. And, particles will lose momentum when they emit a photon. Also important is that for the purposes of particles bouncing around, a photon can have “negative” momentum.

So, two electrons come close to each other. One of them spits out a photon and as a result, loses that momentum, causing it to go off in a direction. The other electron absorbs the photon and gains that momentum, causing it to fly off in the other direction. As a result, the electrons repel each other.

Something similar happens when, say, an electron and proton come close, except that the momentum is “negative” so the electron and proton end up flying towards each other.

Photons are little bits of energy that help with the force that makes magnets stick together or push apart. When you have two charged things, like when you rub your socks on the carpet, they make a kind of energy field around them.

This energy field can send out waves, like when you throw a rock in a pond and it makes ripples. The waves are made up of photons, and they carry the force that makes things with opposite charges stick together and things with the same charges push away from each other.

So, photons are like messengers that carry the energy that makes the force work. They travel through the air and bump into other charged things, making them stick together or push apart.

Photons are little bits of energy that help with the force that makes magnets stick together or push apart. When you have two charged things, like when you rub your socks on the carpet, they make a kind of energy field around them.

This energy field can send out waves, like when you throw a rock in a pond and it makes ripples. The waves are made up of photons, and they carry the force that makes things with opposite charges stick together and things with the same charges push away from each other.

So, photons are like messengers that carry the energy that makes the force work. They travel through the air and bump into other charged things, making them stick together or push apart.

Think of a photon as an event.

Lets look at an example: we know that light is an electromagnetic wave but light can knock an electron. So when light propagates through a vacuum we can describe it as a wave. But when it interacts with something like an electron it can be treated as a particle with momenta and use principles like conservation of momentum and conservation of energy.

So the interaction that light makes is a photon. You can describe the interaction with a particle.

This is the key idea behind virtual particles. You have an interaction, in theory the interaction happens through some field but you can model it like a particle with some momenta, mass, spin getting transmitted.

So lets say we have an electron and a proton making a hydrogen atom. Can we model the electromagnetic interaction between them as photos bouncing between them? Yes. Is that whats going on? No. Just think about it how would the proton “know” where to “shoot” that photon to “hit” the electron. We know that the potential is spherically symmetric around a proton and an electron. They are interacting through the EM field. Where the electron (lets say) happens to be, thats where the photon happens.

How do photos transmit the EM force? Well we are on backwards here. We call an EM interaction a photon.

Whats actually going on is a bit of a mystery.

Think of a photon as an event.

Lets look at an example: we know that light is an electromagnetic wave but light can knock an electron. So when light propagates through a vacuum we can describe it as a wave. But when it interacts with something like an electron it can be treated as a particle with momenta and use principles like conservation of momentum and conservation of energy.

So the interaction that light makes is a photon. You can describe the interaction with a particle.

This is the key idea behind virtual particles. You have an interaction, in theory the interaction happens through some field but you can model it like a particle with some momenta, mass, spin getting transmitted.

So lets say we have an electron and a proton making a hydrogen atom. Can we model the electromagnetic interaction between them as photos bouncing between them? Yes. Is that whats going on? No. Just think about it how would the proton “know” where to “shoot” that photon to “hit” the electron. We know that the potential is spherically symmetric around a proton and an electron. They are interacting through the EM field. Where the electron (lets say) happens to be, thats where the photon happens.

How do photos transmit the EM force? Well we are on backwards here. We call an EM interaction a photon.

Whats actually going on is a bit of a mystery.