The universe could have begun without a beginning.

The universe could have begun without a beginning.

Well that’s just utter nonsense if you ever heard it, right? I literally just contradicted myself. True, but let me explain what I’m trying to convey with that sentence.

A common problem people have with trying to come to terms with the Big Bangis the weird, very uncomfortable feeling of the word beginning in the context of the universe. And it’s a very reasonable feeling to have — after all, any time we define a “beginning” for something, it’s not really the beginning. There was always something that preceded it. Cause and effect.

Your life didn’t begin with just you, it began with your parents. Before your parents, there was all the life on Earth that existed before your parents as your ancestors. Before that, you had nucleic acids self-replicating into other nucleic acids. Those nucleic acids were made out of heavy elements forged inside a supernova explosion. The star that made that explosion was born from that of other stars, back to the first stars which were made from the first hydrogen and helium of the universe. That first matter coalesced from energy, as energy began to take on distinguishable forms after the universe expanded enough that all the physical forces and interactions were no longer identical. And before that…

Here’s where things always get dicey.

You probably have seen a diagram like this before:

📷

(Image Credit: University of Cambridge/CTC[1])

Let’s talk about this thing at the bottom called the quantum gravity wall.

There’s a point, about 10−4310−43 seconds after the “beginning” (whatever thatmeans), before which we can no longer even describe events.

During this first 10−4310−43 seconds, called the Planck era, information, travelling at the speed of light (the fastest anything can travel), will have only had the opportunity to travel one Planck length. One Planck length, about 10−3510−35meters, is the interval over which all points in space and time fluctuate enough that our entire coordinate system breaks down. This means not only can we no longer describe an object’s position effectively, but we can’t even describe whether an event preceded or followed another event.

Perhaps we just need better physics (maybe quantum gravity) to understand how the universe behaves on this scale, but right now we are at a loss. The weird part though is that the universe doesn’t necessarily need to be well defined on these scales. For this reason, these fluctuations are often called quantum foam. It’s perfectly reasonable for spacetime to always be fluctuating on these scales, but still be well defined on the larger scales. Everything is fluctuating on quantum scales and mostly well defined on the macroscopic. That’s basically the crux of all quantum mechanics. There’s no reason why gravity can’t be the same way.

The problem is then, how do we go about describing the first 10−4310−43 seconds when we can’t even describe causality effectively during this period of time? Maybe causality itself isn’t defined on these scales. That would be weird. Without causality, can we even really define time any more? Or space for that matter? Or anything? Did this period of time really last only 10−4310−43 seconds then? What would that even mean if “duration” has no meaning?

The chain of events that represents the course of the entire history of the universe might be asymptotic. This means that as we approach this point that we’re calling t = 0, our ability to describe events is no longer defined, because the continuity of causality itself asymptotes. The universe began as an infinitely fluctuating, infinitely dense, infinitely compact, infinitely energetic, infinitesimally sized, soup of energy. And it existed for an undefinable amount of time in this way, until it expanded enough that information of any kind could propagate longer than a Planck length, and causality came into clearer definition. This is what we have been effectively calling the Big Bang.

So maybe that makes the Big Bang an effective beginning to the universe, but perhaps the universe just “existed” in an undefined state, for an undefined amount of time, before it came into clarity. But if nothing is defined, then it effectively doesn’t exist yet anyway.

This is a very unsatisfactory answer for most people, since it makes it sound like the universe just fizzled itself into existence.

…zzzzzzzzZZZZZOOP and there is the whole infinite universe.

It just doesn’t feel right that we can have existence without something preceding existence right? The trouble is, if something preceded existence, then clearly we haven’t included all of existence in our very definition of what existence comprises.

So, regardless of our discussion of our own observable universe, existence is either infinite or it isn’t. And depending on whom you ask, you’ll always get a different opinion on the matter, because, well, we don’t actually really know yet.

But the Planck era represents a pretty gigantic roadblock for us being able to figure that out. Unless we get some pretty divine insight from developing a grand unified theory of everything, including a fully fleshed out metric for quantum gravity and how it relates to the other physical forces, the Big Bang pretty much signifies the real beginning of everything, even though it really wasn’t a very exciting beginning, or even really a true beginning.

If anything, it was just a phase transition from not being able to describe causality to being able to describe it.

And then, after reaching this conclusion, we get the even spookier question:

Well… Why?

An infinitely near-infinitely compacted universe (meaning, infinitely close to being infinitely dense in energy) would be immediately driven to start expanding. The moment time exists, the universe is expanding. Perhaps the progression of time is tied to the progressing rate of expansion of the universe rather than the other way around. Or perhaps they are actually the same physical concept. Perhaps all of this is tied together in some unbelievably elegant way that we just haven’t figured out yet.

And yet still that weird question hangs in the air.

How does anything even exist in the first place?

Welcome to the astrophysicist’s version of an existential crisis.

For all we know, the answer to this question could just be a tautology. If existence at one point didn’t exist, then it wouldn’t just start existing, because there wouldn't exist anything to beget its existence, because that’s what existence is. Therefore it must start by existing in the first place, and there simply was no before.

Yeah, it doesn’t sit well with me either. But that is the universe that we observe.

The word “before” doesn’t even make much sense if time didn’t exist yet. But perhaps there is another temporally infinite plane of existence beyond our observable universe from which our universe was born from. Multiverse and cyclical universe theories are popular and certainly not unheard of, not to mention countless religious interpretations on the origin of the universe.

But we have yet to see particularly strong tangible evidence for any of these yet. Some would argue that existence itself is the evidence, but that really is the dilemma we have here. We have the universe that we observe to work with, and that is what we observe, and that presents us with what we can say about the universe.

Beyond that, well, I’ll leave that to the reader to ponder over.