We need understand what is energy and what is matter made up of first.
1) Let us analyze the smallest single charged particle, electron. The electric field around electron should be determined by electron. If we track down the electric field down to the center of electron, the center point causes the electric field direct to all direction. This does not make sense. The big possibility is the center is empty.
2) An important experiment: Pair production test.
pair production experiments shows that passing a gamma ray through the strong electromagnetic field near the nucleus results in the creation of an electron and positron. this means the electron and positron are made up of electromagnetic field. Magnetic field is created by electric field too. So the positron and electron are composed of electric field.
3) The properties of electric field: electric field tends to be in the same direction and even density. Only sphere structure can satisfy both properties. If you leave a electric field there, it will quickly form the sphere structure by itself with the field radiating to all directions. Since the direction property, electric field forms two kinds sphere structure, one is the electric field towards the center, the other one is outwards the center. They have the same size but opposite field direction. Those are positron and electron.
Two conclusion: 1) particle is made up of electric field. 2) electron is not an small particle, its field can reach far away.
I will write more when I get chance