What is hologram?
You’ve seen holograms before – they are popular in movies and pop culture everywhere and play roles in science fiction. Light bounces off some sort of surface to create a pictorial 3D image. But to think that we are living in a hologram… Would that be too far fetched? It sounds awfully absurd.
On the farthest reaches of physics, The Holographic Principle suggests the notion that our reality as we know it is nothing but a simulation of 3D information projected by some sort of 2D surface, known as a hologram.
The principle/theory that postulates this notion that reality is a hologram is known as the holographic principle. But before we get into that, it is necessary to explore the origins of this principle – The black hole information paradox.
The Black Hole Information Paradox
When we talk about information in physics we are usually referring to one thing – the wave function of a particle. As we know it, one law that cannot be broken states that information cannot be destroyed. It can shift shapes and forms and metamorphose into weird shapes and sizes but it can never be destroyed so that it becomes nothing.
Not too long ago, Stephen Hawking proposed that black holes emit radiation. (Known as Hawking Radiation) And indeed, black holes do emit information, just the same way as they swallow information (For example, an astronaut who was a little too daring to cross the black hole’s event horizon). So black holes emit information, and so they evaporate within a finite length of time into …. nothing?
Doesn’t this violate the absolute FACT that information cannot be destroyed ?
The holographic principle to the rescue
This is where the superhero of the day steps in. Now, how does encoding the information a black hole has swallowed onto a hologram sound like to you?
To solve this paradox, physicists Leonard Susskind and Gerard’t Hooft made a daring and controversial proposal that the information thought to be swallowed by a black hole was never actually ingested into the deep abyss of the black hole. Instead, the 3D information has been ENCODED onto the black hole’s 2D event horizon. And it is there to stay, forever. Information in this way would be preserved on the surface of a black hole.
As 3D information in a black hole is now supposedly encoded onto its 2D horizon, intuition suggests that 3D pieces of information like you and I are simply codes on the Universe’s horizon.
This means that nothing is objectively and physically real after all, in a sense. Our brains fool us into thinking reality is, well, real. But truthfully, that is just our brain’s only option to make sense of the world around us. This implies that reality is nothing but an illusion projected by our brains.
In addition to this claim, say we add exactly 1 bit of information to a black hole. The black hole will grow EXACTLY by one square Planck unit. It is known that the information content of a black hole is directly proportional to the surface area of a black hole and NOT it’s volume, surprisingly, which is very strange and odd as information is 3D and should rightfully be “eaten” by the black hole, right?
Again, intuition suggests that this is a pretty substantial claim that 3D information is really somehow encoded onto the 2D horizon (In relation to the direct proportionality of its info content and surface area).
If the holographic principle is true, space time would be made out of bits around the Planck length ( 10^(-48) times smaller than the width of an atom, also known as ridiculously tiny), just like how tiny dots make up an image on a magazine.
The holographic principle is one that also is entangled with quantum gravity (A theoretical unification of quantum mechanics and general relativity) and also string theory. Yes, there is more to this absurdity! The upcoming article will explore the relationship that the holographic principle has with quantum gravity and string theory.
Sit back, relax, and give your brain a break. Part 2 of this article is coming. It is not over yet.