Are aliens just humans from the future?

What if the UFOs in our skies aren't visitors from a distant star system, but tourists from our own future? It sounds like science fiction, but it's a hypothesis that has been gaining traction in certain academic circles. The idea is simple and unsettling: the beings we call "aliens" might actually be our descendants, traveling backward through time to observe their own evolutionary past. This isn't just a Reddit shower thought. It's a formal model proposed by a biological anthropologist, grounded in evolutionary trends, the physics of general relativity, and patterns found in decades of reported encounters.

The extratempestrial hypothesis

Dr. Michael P. Masters, a professor of biological anthropology at Montana Technological University, coined the term "extratempestrial" to describe this idea. In his 2020 book Identified Flying Objects and its 2022 follow-up The Extratempestrial Model, Masters argues that the beings described in UFO encounters aren't extraterrestrial at all. They're extratempestrial, meaning they come not from another place, but from another time. Masters uses what he calls an abductive approach, logically inferring the best explanation from available evidence. He looks at the consistent features of reported encounters across cultures and decades: humanoid beings with enlarged craniums, reduced facial features, large eyes, small bodies. Then he asks a straightforward question: what if those features aren't alien at all, but the logical endpoint of human evolution?

Why "aliens" look suspiciously human

The classic Grey alien, the archetype burned into pop culture since the Betty and Barney Hill abduction case in 1961, is strikingly humanoid. Large head, small body, big eyes, no hair. These are not random features. Masters points out that human evolution has consistently trended toward larger brain-to-body ratios (encephalization), increased cranial volume, and reduced jaw and facial structures. Our skulls have been getting rounder and our faces flatter for hundreds of thousands of years. If you extrapolate those trends forward by millions of years, you end up with something that looks remarkably like the beings described by people who claim to have had close encounters. The large, dark eyes could reflect adaptation to different light conditions or reliance on visual processing over other senses. The gracile bodies could result from reduced physical demands in a highly technological civilization. Even the reported telepathic communication fits neatly: if language and cognition continue to evolve, direct neural communication isn't far-fetched as an endpoint. In other words, the Grey might not be an alien body plan. It might be the human body plan, given enough time.

The physics isn't as impossible as you'd think

The biggest objection to the time travel hypothesis is obvious: time travel to the past is impossible. Except physics doesn't quite say that. General relativity, Einstein's theory of gravity and spacetime, permits solutions that include closed timelike curves (CTCs), trajectories through spacetime that loop back on themselves. These were first discovered by Willem Jacob van Stockum in 1937 and later confirmed by Kurt Godel in 1949, who found a solution to Einstein's field equations that allows CTCs in a rotating universe. Since then, physicists have identified several theoretical mechanisms that could enable backward time travel: traversable wormholes, the Alcubierre warp drive, and Tipler cylinders among them. None of these are currently buildable, but they're not violations of known physics either. They're engineering challenges, not logical impossibilities. The Novikov self-consistency principle even provides a framework for resolving paradoxes: any action taken by a time traveler was always part of the timeline. No grandfather paradox, no contradictions, just a self-consistent loop. A civilization millions of years more advanced than ours might have solved these engineering challenges. We went from the Wright brothers to the Moon in 66 years. What might a species do with a million more?

What they'd be doing here

If future humans could travel back in time, why would they? Masters has a straightforward answer: the same reasons we study the past today. Anthropologists travel to remote regions to observe indigenous cultures. Paleontologists dig up fossils. Historians pore over ancient texts. A future civilization with time travel technology would have the ultimate research tool: direct observation of their own evolutionary history. Masters calls some of it "archaeological tourism." Some of the most visited sites in the modern world are ancient ones, the pyramids of Giza, Machu Picchu, Stonehenge. Imagine being able to visit those places not as ruins, but as living, functioning societies. There would be no shortage of future humans willing to pay for that experience. The reported behaviors in close encounters also fit this model. Abduction accounts frequently describe medical examinations, biological sampling, and what appears to be genetic study. If future humans were monitoring their own evolutionary lineage, these are exactly the kinds of procedures they'd perform. Not malicious experimentation, but biosurveillance, cataloging traits and genetic markers across their ancestral timeline.

The Fermi paradox, reframed

The Fermi paradox asks: if the universe is so vast and so old, where is everyone? Despite billions of potentially habitable planets, we've found no definitive evidence of extraterrestrial intelligence. The extratempestrial hypothesis offers a reframe. Maybe we're not looking for the right thing. If the beings visiting Earth are from our future rather than from another star, then the silence of the cosmos makes more sense. We wouldn't expect to pick up radio signals from a civilization that doesn't exist yet. And their vehicles wouldn't need to cross interstellar distances, just temporal ones. This doesn't solve the Fermi paradox entirely, but it does shift the question from "where" to "when."

The cryptoterrestrial connection

In 2024, researchers affiliated with Harvard University published a paper exploring the "cryptoterrestrial hypothesis," the idea that unidentified anomalous phenomena (UAP) might be linked to intelligent beings already present on Earth, concealed underground, on the moon, or even passing as humans among us. The paper, published in the Journal of the International Society for the Philosophy of Chemistry, outlined four categories of possible cryptoterrestrial beings. One of them directly references Masters' work: future humans who have traveled back through time and established a covert presence in earlier epochs. Dr. Masters himself contributed to this research. In interviews about the paper, he emphasized that the time travel model is one of several possibilities worth taking seriously. "We're not saying this is right," he told CBS News. "We're saying these are some potentialities, some possibilities to help explain the origin of these beings." The paper was described by its own authors as a "speculative thought piece" and was not peer-reviewed in the traditional sense. But the fact that it came from researchers at Harvard and Montana Tech signals that these ideas are at least being entertained at the edges of mainstream academia.

The criticisms

Not everyone is convinced, and the objections are serious. Astrophysicist Neil deGrasse Tyson has called the hypothesis illogical. UFO skeptic Robert Sheaffer criticized Masters' work for relying on "the belief that time travel is not only possible, but real." And astronomer David Darling, while acknowledging the hypothesis is "just as reasonable" as the extraterrestrial hypothesis, argued that both are "highly unlikely and unnecessary." His core point: there's no compelling evidence that the phenomena being explained are artificial or non-terrestrial in the first place. The hypothesis is also, by its nature, unfalsifiable. There's no experiment you can run to prove that a specific UFO is a time machine. The model explains the evidence neatly, but explaining evidence isn't the same as predicting new evidence. That's the line between a hypothesis and pseudoscience, and the extratempestrial model currently sits right on it. There's also the bootstrap problem. If future humans are visiting us, their existence depends on the timeline proceeding in a way that produces them. Any interference could, in theory, alter the future. The Novikov principle addresses this, but it does so by assumption, not by proof.

Why it's still worth thinking about

The extratempestrial hypothesis might not be right. It might not even be testable in any meaningful way with current technology. But it does something valuable: it forces us to question our assumptions. When we see something we can't explain in the sky, the default framing is "where did it come from?" Masters' model asks us to consider "when did it come from?" That's a fundamentally different question, and it opens up a fundamentally different set of possibilities. It also highlights how narrow our thinking about intelligence tends to be. We assume that contact with non-human intelligence means contact with a separate species. But what if the most alien intelligence we ever encounter is just us, separated by a million years of evolution? The universe is strange enough that the answer to "are we alone?" might turn out to be stranger than we imagined. Not "no, there are others out there," but "no, they're right here, and they're us."

References