Beyond the smallest particles, Electrons, Quarks, tau-Neutrinos, etc there are sub-sub atomic particles in the Sea of Dirac.
These sub-sub atomic particles make up all the above particles including mass and charged Protons, Neutrons, neutrinos, etc, and extremely massless and chargeless Photons.
Protons, Neutrons, and Electrons have a permanent either positive, neutral, or negative spin.
The Electron spin is stronger than the Proton/Neutron spin.
When an Electron falls back from a higher excited orbit to the normal lower orbit it remains in the same spin, decreases its mass, increases its charge, and releases a Photon.
Spin is a motion whereas charge is an effect.
Photons are more or less spherical particle-like waves of masses of these sub-sub atomic particles that are in a frequently varying negative/positive, repelling/attracting motion creating the Photon's electromagnetic wave.
Photons do have spin but the effect is extremely weak due to very small momentum.
The sub-sub atomic particles constituting the Photon remain in their locality like the water in the wave from a ship or a tsunami in the Sea/Ocean.
Quantum Entanglement is a string made of these sub-sub atomic particles between two Photons and then two Electrons.
Gravity is also a quantum entangled string between all particles with mass.
Gravity and quantum entanglement of photons and electrons work dominantly on the macrocosmic scale whereas the strong and weak forces only work and are dominant on the microcosmic or atom scale.
How quantum entangled strings composing gravity, are produced is unclear.
All these particles and strings phenomena made of sub-sub atomic particles interact in a repelling or attracting manner caused by the same spin or opposite spin of these particles.
Electromagnetism is caused by the spin of Electrons and Protons.
Electromagnetism expresses in the interacting electromagnetic fields composed of sub-sub atomic particles in the Sea of Dirac around Electrons and Protons which are also composed of sub-sub atomic particles.
Whether the strong force between Quarks within the Proton and even the weak force creating radiation is either a string-like entanglement or a sub-sub atomic field like in electromagnetism is unclear.
The force of the Gravity strings is weak within the dimension of the atom because the gravitational force is predominated by the Electro-Magnetic, weak and strong forces.
Like the Quantum Entangled strings the sub-sub atomic particles creating the Gravity string also remain in their locality. Strings might be very thin cosmic long helixes with some unmeasurable electromagnetic field.
Gravity, Electromagnetic, strong, and weak forces are all the same phenomenon and made of the same sub-sub atomic particle but with different strengths.