In A Nutshell
Parallel universes are cool to think about, but they have always seemed so far-fetched. However, cutting-edge physics research has shown that creating a “designer universe” is not only possible, but within the reach of human understanding. Technological barriers need to be overcome, but the theoretical groundwork exists.
The Whole Bushel
Multiverse theories are all the rage in modern physics. Every year, new theories emerge, although most fall by the wayside. A common theme through all of these theories is that multiple universes exist and were created by natural means without any intelligent guidance.
While that is surely the most popular viewpoint, some physicists have adopted the opinion that parallel universes exist, but they have not occurred by natural means. Rather, they have been created by technologically advanced beings. That seems like a pretty far-fetched idea straight out of Star Trek, but modern physics provides all the necessary ingredients to make a designer universe.
What would a civilization need to build a universe? To figure this out, simply look at the big bang and the theory of inflation. The theory of inflation is the idea that the universe exponentially expanded right after the big bang and then settled down to a normal rate of expansion. The physical mechanism for this expansion is called the inflaton field. There is no consensus as to what the inflaton field actually was, but if a scientist were to learn exactly its properties, he might be able to control it.
In order to set up a big bang, the key ingredient is an amount of matter compressed in a very small area. Shockingly, only a couple of kilograms of matter would be necessary, provided that it is compressed into a small enough area. A civilization would then need to gain control of the inflaton field, the theoretical mechanism of inflation.
In the chunk of matter that kicked off the big bang, the inflaton field experienced quantum fluctuations that made it bounce around different energy levels. Once the inflaton field reached a specific energy plateau, it exerted an anti-gravity force that caused the universe to inflate rapidly. A sufficiently advanced civilization would need to be able to control the inflaton field to force their model universe to expand.
Those are the ingredients. Unfortunately, the current technological capacity of the human race isn’t sufficient to create a designer universe.
Not only are the mathematics behind the inflaton field not fully understood, we do not have devices capable of matching the compression needed to create a “universe nugget” of sufficient density. Theorists such as Alan Guth have shown that once this density is achieved, the new universe would begin to bulge out of its parent universe, eventually completely disconnecting into the space-time continuum. When the new universe splits off, its inhabitants would probably be unable to communicate with their parent universe.
This concept leads to some disconcerting realizations. If we are a designer universe, we would never be able to prove that our universe is not naturally created. In a designer universe, the initial conditions look just like a big bang. A scientist attempting to prove that we came from somewhere else would have to somehow discover signatures in our universe that point to our unnatural genealogy.
Alan Guth believes that certain black holes are this signature. The black holes in question might show that our universe was artificially created or that artificial universes have already been created in our universe. Either option is equally mind-blowing, but we still need proof.
Show Me The Proof
The Telegraph: Are we living in a designer universe?
Of Particular Significance: Cosmic Conflation
NY Times: Physicist aims to create a universe, literally