it is said that charge and mass possess similar properties .so my question is that can a charge move with the speed of light like in einstein maxwell theory.if then would there be any change in the field so produced….

Dear student, charge carried by electromagnetic waves are basically the electrons which move with velocities very close to the velocity of light but not equal! This is because any charge would be associated with some mass and any non zero mass cannot move with speed of light.

Regards

Sumit