This is a fascinating news item. Hold on to your beanie hats with the propellers on them.
Scientists may have actually detected the grain or pixels of the universe. This may mean that our reality, everything we see and do, our entire universe in fact, is like a 3-dimensional holographic image of sorts projected from somewhere else. Talk about a one-two punch.
This story starts at a German-British gravity wave detector called GEO600 in northern Germany. They’ve been trying to find Einstein’s theorized gravity waves for 7 years. It is believed these waves in space-time itself are created by titanic events in the universe like supernovae or collisions of black holes or neutron stars. The detectors work by splitting a beam of light and sending it in two directions perpendicular to each other, bouncing the light off of mirrors, and then recombining it to look for any changes in the interference pattern. If this pattern shifts, if might have been caused by one of the perpendicular pathways being stretched or squeezed by a passing gravity wave. The group that detects these waves first will be the first gravitational wave astronomers.
These researchers ran into a problem though. Their detectors kept getting this background noise that would not go away.
Enter Craig Hogan, physicist at the Fermilab particle physics lab in Batavia, Illinois and recent appointee as director of Fermilab’s Center for Particle Astrophysics
He’d been thinking long and hard about what’s called the Holographic Principle. The idea here is that the total amount of information or entropy a space can contain depends on its surface or the boundary of that space and not its volume as you might suppose. So as an analogy, the amount of plastic used in a beach ball would be directly related to the amount of information that there can be on the inside of the ball.
This sounds counterintuitive but this mathematical principle actually works when calculating the entropy of a black hole. In 1972, Physicist Jacob Bekenstein discovered that a black hole’s entropy or information content, is proportional to the surface area of its event horizon. The progenitor star that exploded and became the black hole then could have all the information about its 3D structure encoded in the 2D event horizon.
In the early 90’s, physicists Leonard Susskind and Gerard ‘t Hooft extrapolated the holographic principle from a black hole’s event horizon to the cosmological horizon which is essentially the boundaries of the observable universe.
This would mean that the universe could essentially be described as a 2-dimensional construct embedded in boundaries of the cosmological horizon (observable universe). Our visible universe could then be seen as a 3-dimensional representation of processes happening on that distant 2-dimensional surface. The analogy with a hologram is not perfect but it does help a bit. A normal hologram on your credit card is a piece of plastic with a 2D pattern etched into it. When light shines on it a 3D pattern emerges.
Ok, back to Hogan. He realized that if this principle could be applied to the universe, then each tiny bit of our horizon would be linked or mapped to our reality somewhere inside. The tiniest bit of anything allowed by quantum theory is called a planck length which is 1.6 x 10 -36 meters. That’s a hundred billion billion times smaller than a proton. This is as small as small can get folks. This is the fundamental unit of length or grain allowed in space-time. Any fraction of it therefore has no meaning. Half of a planck length makes no physical sense. It would be like half of an electron.
Needless to say, this is so unimaginably small that there’s no conceivable way to examine the universe at this scale. We may, though, have a workaround…
Since, in general, surface area is less than its associated volume, each grain in the surface of our horizon must correspond to a bigger grain in our world. Imagine dots on our beach ball. Each dot would map to a much bigger dot inside the ball in order for the 1 to 1 relation to hold. That’s the key concept right there. This is what Hogan realized. He figured, that if we had a measuring instrument detailed enough, we could potentially see the pixels or grain or planck length of space-time because the holographic version of them in the universe would have to be much bigger than they really are on the surface.
Hogan even predicted that GEO600 would be sensitive enough to detect the grain of the universe. He approached the company before he knew they were getting noise. When they sent Hogan a plot of the noise it matched his prediction.
“It looks like GEO600 is being buffeted by the microscopic quantum convulsions of space-time,” says Hogan.
The other bit of intriguing evidence supporting this idea comes from theorist Juan Maldacena. He actually showed that a hypothetical universe of 5 dimensions has physics inside it that match the physics on its 4 dimensional boundary. I don’t know how he did it but the particles that interact on the surface corresponded exactly with the interacting strings on the interior. The trick now of course is to apply this to our non-hypothetical universe.
As compelling as some of this evidence is, keep in mind that no one knows if it is true yet. Most scientists consider this more of an idea or hypothesis than a theory.
If it’s true it’s a double-edged sword. It would mean we may never see gravity waves because the resolution of the universe is too low. Gravity waves have great potential and I’d hate to see them impossible to verify.
The other side of that sword is pretty cool though. What if all this is true?
Hogan has said:
“Forget Quantum of Solace, we would have directly observed the quantum of time…It’s the smallest possible interval of time – the Planck length divided by the speed of light.”
The elusive theory of everything (quantum gravity) could also get quite a boost from this. Certain approaches to string theory tie in nicely to this theory and some don’t. Cutting away some of the non-holographic trash would aid greatly in this endeavor.
Anything that helps us figure out how space-time bubbles out of quantum theory is awesome in my book.
My only question now is should I return my Hi-Def TV if we live in a low-res universe?