Either this universe emerged for some unknown reason or it was created by an advanced civilisation. If this universe emerged without an intelligent force creating it, but also if it always existed, it can be called real. The other option is that this universe is a virtual reality. Sadly, it is not possible to do an experiment that will show which option is true. Some pundits nevertheless believe they can prove that this universe is a virtual reality by demonstrating that underlying properties are digital, meaning that the lowest level of reality is just numbers that can be represented in a computer memory.
How might that work? For instance, a television screen consists of more than a million tiny dots. Every dot has a number. Every dot has a colour. The colour is selected out of a list of colours. Every colour has a unique number too. So every dot has a number and every colour has a number. For example, dot 759,214 might have colour 124,117. From a distance you may see a person, but the lowest level of the television screen is just numbers. You can apply this idea to represent a universe.
The problem with this reasoning is that being digital is a property, not a cause of existence. Perhaps real universes are digital too. The argument of using properties to prove that this universe is a virtual reality comes in different forms. For example, some pundits claim that in quantum physics reality is a sequence of states with nothing existing or happening between the states. This may signify that reality is generated by a computer. That may be so, but it can also be true for a real universe.
Other pundits claim that it is unlikely that this universe emerged by chance. For instance, there is an argument stating that this universe is designed for life because the laws of physics and the values of physical constants seem just right for life to exist. Even if that were true, there may be an unlimited number of universes with different physical laws and constants, and this universe may just be one of them that accidentally is just right. In any case, nobody would make this claim if the universe didn’t support life.
Then there is the Fermi Paradox. It seems likely that there are extraterrestrial civilisations in our universe but there is no evidence for the existence of these aliens. “Where is everybody?” the famous physicist Fermi once asked. Perhaps civilisations tend to die out before they become advanced. Or maybe we just overestimate the probability of advanced civilisations contacting us. It could also be that Earth and humankind truly are at the centre of the universe, which might indicate that we are living inside a simulation.
Also very interesting is quantum entanglement. Some particles interact directly with each other regardless of the distance between them. That means that if one particle is at one end of the universe, while the other is at the other end, they still may interact directly as if there is no distance between them. This mocks our idea of distance, but it also can raise questions about the age of the universe as it is based on the estimated size of the universe.
The observer effect might be the best evidence we have of this universe being a virtual reality. Several types of small particles normally don’t exist and only come into being when someone observes them. If this universe is a virtual reality, it would be a waste of memory and processing power to represent them all the time. In a real universe these small particles might or even should always exist even if no-one is watching.
Featured image: Tunnel of the Large Hadron Collider (LHC) of the European Organization for Nuclear Research. Julian Herzog (2008). Wikemedia Commons.