UFOs aren't alien spacecraft — they're time machines, operated by future humans.

That's the shocking thesis of Michael Masters, a professor of biological anthropology at Montana Technological University. According to Masters, who's spent years researching UFOs, these future humans might be traveling back in time to study their ancestors — us.

Rather than an adorable little ET looking for a ride home, we might be dealing with distant relatives coming over for a family reunion. Get the guest room ready; things are about to get very weird.

Masters' idea is not as outlandish as it may seem. The concept of time travel, though still speculative, is taken seriously by many scientists. Modern physics, including quantum mechanics and Einstein's theory of relativity, shows us that time might not be a straight line. Relativity teaches us that time can bend and stretch with speed and gravity, while some quantum theories even suggest parallel timelines and nonlinear time.

If these theories are correct, time travel could move from the wild world of science fiction to a scientific reality.

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