If there is a universe, and no observer is around to perceive it, does it exist?
My answer is, probably; in fact it almost certainly does. We can say this with a fair degree of confidence because we know the universe has existed for around 13.8 billion years and life on Earth only for about a quarter of that, humans only for a minuscule fraction. The universe had to get to the state it was in when the first life here or somewhere else in the cosmos was able to perceive it; thus, it had to exist for a time without any observers.
But what about reality?
One way to define reality is our minds’ approximations of the universe based on our perceptions and experiences. Looked at in this perspective, reality is then different for every organism capable of higher cognitive functions (i.e. asking existential questions) since we all are unique individuals, and it is different still for organisms capable or perceiving but not wondering. From a lowly ant all the way up to Neil deGrasse Tyson, virtually every unique organism has its own version of reality. But then how can the universe really exist independently after all?
The answer is simple enough: reality and the universe are not one and the same.
If you go down to the quantum level–or even the atomic–you see that the universe is a lot like bits of data in a computer, all working together in ways that create the laws and processes that govern the universe. We can’t, however, perceive atoms and quantum particles; it is our brains that render the accumulation of this data into what we call reality.
Imagine a digital photo saved on the hard drive of your computer. On your hard drive, that photo is raw data that makes no sense to you, but makes perfect sense to the computer. Access the photo and suddenly that raw data turns into an image on the screen that your mind can perceive, and you see a photo. Now, say you turn your monitor off; the photo still exists (on your computer as raw data), and yet your brain can no longer make sense of it.
Perhaps the universe, then, is like the photo; the eyes, ears, nose, mouth and skin access the raw data, and, through the brain, render it into a perceivable image that the consciousness knows as reality.
Go back to my original question: Does the universe exist without an observer? Yes, but reality, I think, does not. Perhaps the universe is what exists, objectively but incoherently to us, and reality is what our brains transform this incoherence into–the image that we need to make sense of the raw information flow. Perhaps reality is merely an evolutionary trick to help life make sense of everything.
In an earlier post I wondered if our ability to ponder the universe was part of a greater natural process that may ultimately lead to a universal self-awareness. Perhaps this answer comes close, or perhaps everything is truly random and chaotic. I can’t say for sure, but I do think it’s worth thinking about.
I will probably never know, of course, but I will always be an observer.