Jetso wrote:
It is not known whether or not retrograde time travel is possible.
Some theoretical (e.g., unproven or unprovable) mathematics
may indicate that retrograde time-travel is
possible, but only if certain exotic (e.g., non-existent) substances and infinite energy are available.
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The mere fact that science may not yet adequately explain an object, event, or experience does not mean the immediate explanation should automatically default to a conspiratorial, extraterrestrial, paranormal, or supernatural cause.