What is radiant heat?

Radiant heat is what you feel when heat transfers from a warm surface to a cooler surface.  Radiant heat works with the laws of physics - not against them.  It heats objects in its path, which then re-radiate heat to the air.  This is how the sun heats the earth.  (Notice how much warmer you feel standing in direct sunlight, as opposed to a shaded area under a tree.)