Researchers in the US are trying to work out whether the universe is actually a 2D hologram.
Physicists believe it may be possible that life as we know it could be an optical illusion created by light diffraction.
They say the universe could be made up of tiny pixels 10 trillion times smaller than an atom.
The government's Fermi National Laboratory in Illinois has now switched on a machine called a holometer that could help researchers to figure it out.
The holometer measures the quantum jitter of space, and will look for holographic noise.
Physicist Aaron Choi, the project’s lead scientist, said: "If we find a noise we can't get rid of, we might be detecting something fundamental about nature - a noise that is intrinsic to space-time.
"It's an exciting moment for physics. A positive result will open a whole new avenue of questioning about how space works."
The theory likens the universe to the idea of pixels in a photograph; from a distance one picture can be seen, while close up tiny points that make up the larger whole are evident.
In a paper explaining the theory, laboratory director Craig Hogan wrote: "Some properties of space and time that seem fundamental, including localization (where things are), may actually emerge only as a macroscopic approximation from the flow of information in a quantum system."
The experiment will gather data over the coming year.