There is an interesting hypothesis in physics that basically states we all live in a hologram. If true, this idea would fundamentally change our understanding of reality.
In short, the holographic universe is the idea that the 3D world we see is just an illusion. All of the information for our universe would be contained in a two dimensional space that exists around our universe, and this information is "projected" into our universe creating the illusion of three dimensions. This can be described with the help of a television. A (traditional) television screen is flat and creates pictures in a two dimensional space, yet this space has the appearance of three dimensions.
So, using the TV example, if you look close enough, you'll see that the picture is actually created by many different pixels. A pixel is just a small packet of data that helps to create the bigger picture. Hypothetically, if our universe is a hologram, we should be able to see "pixels" if we look close enough. What is the resolution of the universe? It exists in a scale known as the Planck scale, which is about 10-trillion-trillion times smaller than an atom.
This is where the experiment at Fermilab comes into the picture. As Craig Hogan, the directer of the Center for Particle Astrophysics says, "We want to find out whether spacetime is a quantum system, just like matter is. If we see something, it will completely change the ideas about space that we've used for thousands of years."
This experiment takes advantage of the uncertainty in quantum theory. If information is sent to us in 2 dimensional packets, it would be subject to the same level of uncertainty. If you take space down to an energy level approaching zero, scientists should be able to detect little vibrations in the space itself. If we go back to the pixel idea, if you look close enough at a TV screen you'll reach a scale where you can't store or display any more information, you can't look "any smaller" to learn more. This limit is what scientists at Fermilab are trying to find.
According to the press release, Fermilab states, "Essentially, the experiment probes the limits of the universe’s ability to store information. If there is a set number of bits that tell you where something is, it eventually becomes impossible to find more specific information about the location – even in principle. The instrument testing these limits is Fermilab’s Holometer, or holographic interferometer, the most sensitive device ever created to measure the quantum jitter of space itself."
The Holometer will use two interferometers, each equipped with a one-kilowatt laser, to probe for this "holographic noise." The lasers will be shot to a beam splitter, which will send the laser down perpendicular arms, 40 meters in length, the laser will then be reflected back to the beam splitter and the beams are recombined into one. Scientists will measure how the light recombines and look for fluctuations in the energy of the beam.
Since the light is measuring vibrations, scientists need to be careful to eliminate other sources of vibrations as to not contaminate the experiment. Because the holometer is probing extremely high frequencies (reaching into the millions of cycles per second), then any motion or jiggling or normal matter shouldn't affect it. The biggest interference will probably come from radio waves, but the holometer is designed to identify these signals and eliminate that noise.
Aaron Chou, a physicist at Fermilab, concluded, "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 spacetime. It's an exciting moment for physics. A positive result will open a whole new avenue of questioning about how space works."