our fragile and potentially self-destructing universe. sort of...

If you believe popular science headlines, our cosmos could unravel at any instant. It's very unlikely, but the idea's core questions are still worth asking.

Every few years, popular science outlets talk about a study which says that everything we know, our entire cosmos, is more or less like a soap bubble. Interesting things may be happening inside of it and around the edge of this bubble with whatever is beyond, if there’s anything beyond it that is, but one quantum fluctuation gone wrong, and the whole thing unravels in an instant. Like a Thanos snap, but with quantum foam playing the role of the infinity cojones, and so quick you don’t even have the time to tell Tony Stark that you don’t feel so good.

It is a real hypothesis, and there is real science behind it. But all the pop sci headlines dripping with gloom and doom are committing a very serious mistake. Just because a formula has a valid mathematical answer that ends in a universal apocalypse, doesn’t mean it can actually happen. If anything, we can use the same math to argue that the odds of our reality imploding on itself are extremely low. If they weren’t, we wouldn’t have a universe in the first place.

Okay, let’s rewind for a moment. Why exactly would we just blink out of existence on a random day? Don’t we live in close to entirely empty space? What exactly would blow up and wipe us out of existence at the speed of light, if not faster?

Well, that’s precisely the question. Is our universe really empty space? Is the cosmos almost entirely vacuum at it lowest possible energy state allowed by quantum physics, or is there more energy for the fabric of space-time to release? After all, we know the universe’s ground state isn’t absolutely still, which is why the coldest places we know hover close to absolute zero but can never reach it. So, what if there is a much bigger step down to the lowest energy point than we think?

will the real cosmic vacuum please stand up?

This is known as the false vacuum theory. Rather than having stabilized to its ground state, the universe is stuck in a sort of quantum valley. It’s “metastable” and remains so for potentially billions of years until something in the underlying quantum foam, an enigmatic layer of reality where subatomic particles and antiparticles randomly pop into existence only to annihilate each other, nudges our false vacuum out of this very stable valley and into a true vacuum.

All of that energy contained within our universal bubble would now have a place to go and it would escape instantly, unraveling existence as we know it by the basic laws of entropy. Galaxies, black holes, stars, planets, and us will simply dissolve into quarks, gluons, and bosons. At least this is what the math and simulations using a prototype of a quantum computer say.

If you notice, however, there are two major assumptions in play for the false vacuum theory. The first is that a “metastable quantum valley” exists outside of an equation. The second is that it would be stable for eons until one small nudge dislodges it. On timescales of billions of years, both seem unlikely as even the most unlikely events become a certainty and everything we know about physics says that every particle rushes to assume its lowest possible energy state as quickly as possible.

Unless everything we know about absolute zero is wrong, there just doesn’t seem to be any significant distance to go between what we see around us and a perfect, ideal theoretical point of zero entropy. If we are in a valley, it seems like it’s just millimeters above sea level and our fall would be more like a slow motion plop. And if we’ve been here for 13.8 billion years and incalculably vast numbers of of quantum reactions over at least 94 billion light years, any of which could have triggered our demise, it’s highly improbable that it hasn’t already happened.

is this the real space, is this a quantum sea?

At the heart of stories and studies like this are profound questions about reality and what it means to exist, and not just in a philosophical way but in very concrete terms that can be objectively quantified and demonstrated. The good thing about questions is that we can use them to unravel fundamental truths by asking enough of them and being willing to take the most reproducible and verifiable answers. The bad thing? We don’t always know where to stop because in science, very few answers are truly ever, or exhaustively complete. There’s always a tinge of doubt.

This is how we go from well-proven and thoroughly defended theories like the ΛCDM model of the universe, to exotic musings like the universe being a quantum hologram, simulation theory, and yes, false vacuums. They’re not attempts to be unique or be a pochemushka, but hypotheses trying to answer very fundamental questions. Why are point particles the smallest units of matter? What is zero entropy in a practical sense, is it possible, and why? What happens to matter swallowed by black holes?

So when we talk about the idea that we live in a false vacuum, we need to look at the notion not through the lens of sensationalism or mocking the scientists trying to work on the science behind it. We need to think of it as researchers attempting to provide ways to make sure we understand the behavior of the fabric of space and time, and what its oscillations — which we perceive as gravity waves — really mean in the grand scheme of the universe’s fate.

Cosmic armageddon is one outcome of the equations, yes. But it’s not an answer to the question of how the universe as we know it may end. It’s the byproduct of a very different question, the question of where exactly is the universe and what defines it, highlighting how much we still have left to learn.

Given what we know so far, all we can say is that it’s highly unlikely that we’re in real danger of blinking out of existence if a big enough supercluster quantum farts in the wrong direction. If it was going to happen, we most likely wouldn’t be here, wherever here is, to talk about it. And what that conclusion leaves out are the bigger questions of why we’re still here, where is here, and is there anything out there that may have an effect on us at some point down the line?