Three perhaps not unrelated comments:

Worked on a Navy ship once, many civilian techies, star trek heads all. "If you've seen it on star trek, we either have it or are working on it"

Reich and Tesla got in trouble with US Govt over electrical experiments. they were corresponding with each other.

Report from PA? coal find in a mine, 1850's?, perhaps in Smithsonium Museum?
of Coal lump with a gold chain completely embedded through it, no sign of any possible tampering. Hard coal.

Take your choice: People with gold chains were wandering around in the woods many millennium ago, or time travel is real. Both are possible.