Academic question about the coaxial lines

What is the portion of energy carried by elecromagnetic field inside the coax versus the energy carried by currents in the conductors. I belive that lowering the frequency the greater part of the energy will be transmited with currents rather than EM field. Any comments?

Coax cable currents and EM field in the cable are tied together. You can not look at them as separate phenomena.

Please, allow me to disagree, m8t. If you connect a coax to mains power supply (50 Hz) the energy delivered to the matching load will be transfered mainly by currents in inner and outer conductor. If you prowide rf (500MHz) the energy will be delivered to the load mainly by the field. The only difference is the frequency.

Do you think that at 50Hz does not exist EM field in the cable?

Ofcourse EMF exists, but I think that the main portion of the energy is carried by the currents, not by EM field