Space experts believe we could be living a massive lie in a vast Matrix-esque virtual world dreamed up by advanced artificial intelligence.
Supporters of the seemingly madcap theory include SpaceX boss Elon Musk, celebrity astrophysicist Neil deGrasse Tyson, and theoretical physicist Brian Greene.
Telsa cars founder Mr Musk, who wants to put humans on Mars, appears to be the theory’s most avid supporter that humankind lives in a simulation.
He said the chance of mankind NOT living in a simulation is “one in billions”.
If true, it would mean everything we experience is just lines of code in an advanced programme – in the same way virtual worlds created in computer games are just projections of data.
Musk argues technology is advancing so quickly it will only be a matter of time before we are capable of conjuring hyper-real virtual worlds and someone before us could have got there first unbeknown to humans.
There are other top minds supporting the theory.
Scientist Neil deGrasse Tyson said he thinks the likelihood is “may be very high” our lives are just a computer simulation.
He said: “I’m saying, the day we learn that it is true, I will be the only one in the room saying, ‘I’m not surprised.’”
He said humanity “would be drooling, blithering idiots” in the presence of a potential higher being controlling the supposed simulation.
He even claims we should look out for “glitches” in the world which could be proof of a simulated reality.
Rich Terrile, a scientist at NASA, is also interested in the theory.
He said technology is increasing so fast that “very quickly we will be a society where there are artificial entities living in simulations that are much more abundant than human beings”.
He said: “If in the future there are more digital people living in simulated environments than there are today, then what is to say we are not part of that already?
“If we are not living in a simulation, it is an extraordinarily unlikely circumstance” and suggested it could have been created by our ‘future selves’.”
Theoretical physicist Briane Greene says the idea sounds “nutty”, but said is also “mind boggling” could even be true.
He said it was “easy” to conceive of beings being able to “create an electronic world and thus there would be so many more simulated universes than real ones.”
But, Havarad scientists Lisa Randall said the theory was mere speculation with “no real evidence”.
And, Max Tegmark, a professor of physics at MIT, questioned whether it was “logically possible” to prove we are living in a simulation.