No, it is not possible to convert a proton into two neutrons using only electromagnetic forces while keeping the mass, charge, and spin unchanged. Such a conversion would violate conservation laws and the fundamental properties of particles.
The proton and neutron are two different particles with distinct properties. The proton has a positive charge, while the neutron is electrically neutral. They also differ in terms of their quark composition, with the proton being composed of two up quarks and one down quark, and the neutron having two down quarks and one up quark.
Electromagnetic forces alone cannot change the number of quarks in a particle or convert a proton into two neutrons while keeping the particle's mass, charge, and spin unchanged. These conversions involve changes in the quark composition, and the electromagnetic force alone does not mediate such interactions.
However, it is possible to convert a proton into a neutron and other particles through other processes, such as the weak nuclear force, which governs certain types of nuclear interactions. In beta decay, for example, a proton can be converted into a neutron by emitting a positron (the antiparticle of the electron) and a neutrino.
In summary, converting a proton into two neutrons while preserving mass, charge, and spin using only electromagnetic forces is not possible. Such a transformation would require processes beyond the scope of electromagnetic interactions.