The most interesting theory about the Philadelphia Experiment is that the destroyer did in fact disappear and was teleported across space and time. Supposedly, there was a great number of ingenious scientists (including Tesla and Einstein) that were taking part in the experiment. However, Nikola Tesla was supposed to dead at the time of the Naval experiment.
The theory is that light has to be bent around the ship to make it invisible. To accomplish this, the Navy wrapped the ship's circumference in wire and passed a measured current through it. This caused a huge oscillating magnet to form a magnetic field around the ship, not only bending the light, but space and time as well. The physics of the experiment are reminiscent of Einstein's Unified Field Theory that once you bend light, you are also unwittingly bending space and time as well.
The first time this experiment was undertaken, the ship didn't completely disappear, and an imprint of the hull could be seen sitting in the water. The second time, the ship totally disappeared in a green fog and was sighted in Norfolk, Virginia.
A haunting fact is that when the ship reappeared, the crew were all in a state of disorientation. Some were mentally ill, while other crewmen didn't even return. There were also crewmen that returned embedded in the hull. Later accounts arose about the crewmen, including a former crew member who was involved in a bar fight, and all the participants froze in time, as reported by a local newspaper! There were also accounts of people who were on the ship, spontaneously combusting