"Is The Universe a Hologram? Should We Care?"
If this doesn’t blow your socks off, then Hogan, who has just been appointed director of Fermilab’s Center for Particle Astrophysics, has an even bigger shock in store: “If the GEO600 result is what I suspect it is, then we are all living in a giant cosmic hologram.” [...]
The holograms you find on credit cards and banknotes are etched on two-dimensional plastic films. When light bounces off them, it recreates the appearance of a 3D image. In the 1990s physicists Leonard Susskind and Nobel prizewinner Gerard ‘t Hooft suggested that the same principle might apply to the universe as a whole. Our everyday experience might itself be a holographic projection of physical processes that take place on a distant, 2D surface.
I think the best thing to read on the general kinds of issues this raises is David Chalmers’ paper “The Matrix as Metaphysics”. The key takeaway point is that various hypotheses (maybe the world is a holograph, maybe the world is a computer-simulation, maybe the world is someone’s hallucination) are often presented as skeptical hypotheses when we should probably think of them as metaphysical instead. In other words, instead of saying “everything we thought we knew about the world is wrong and it’s all fake!” we could just say “aha, this is an interesting new fact.” After all, at one point it was determined that what we thought we knew about solid objects was all wrong. Solid objects, it turned out, aren’t actually solid at all—they’re made up of atoms, and the atoms are composed of protons and neutrons and electrons and are actually mostly empty space.
But people didn’t run around freaking out at the discovery that the world is fake and actually it’s all just a bunch of empty space. Instead, we learned that molecules are made of atoms and atoms are made of protons and neutrons and electrons. Further discoveries about the nature of sub-atomic particles are, similarly, interesting and important scientific discoveries but they’re not taken to somehow debunk our previous knowledge of the existence of macroscopic objects. Similarly, if subatomic particles are “really” a reflection from a different 2D surface I think the important thing is to take the revelation in stride, as we have a whole series of scientific revelations about the nature of matter.