A tiny speck of dust

You are standing on a rock a little under 13,000 kilometres wide, spinning through space at over a thousand kilometres an hour, orbiting a star that is itself hurtling around the centre of a galaxy containing somewhere between 100 and 400 billion other stars, inside a universe estimated to hold anywhere from a few hundred billion to two trillion other galaxies, depending which count you trust. None of that is metaphor. It's just where you are right now, reading this. Most days it doesn't feel like that. It feels like whatever is directly in front of you, a screen, a room, a version of your own life that seems far too small and far too stuck to have anything to do with trillions of anything. Both of those things are true at the same time, and that's really what this post is about.

The dark sky that shouldn't be dark

Go outside on a clear night and look up. Most of what you see between the stars is black. That shouldn't be possible, and for a couple of centuries it genuinely bothered people enough to have a name: Olbers' paradox.

Here's the logic. If the universe is infinite, has existed forever, and is reasonably evenly filled with stars, then every single line of sight you could draw from your eye, in any direction, should eventually hit the surface of a star. Not most directions. All of them. Pack enough stars into infinite space and there are no gaps left to see through. The night sky shouldn't look like a few points of light on black. It should look like one unbroken wall of starlight, roughly as bright as the surface of the sun, in every direction, all the time. Day and night would stop being different things.

It obviously doesn't look like that, so one of the assumptions has to be wrong. The one that breaks is "has existed forever." The universe is about 13.8 billion years old, and light only travels so fast. Anything whose light hasn't had the time to reach us yet simply hasn't arrived, no matter how long we wait, because the universe itself hasn't been running long enough to deliver it. The dark patches of sky aren't empty. They're just not finished arriving.

So the darkness between the stars isn't the absence of anything. It's a clock. Every dark patch of sky is telling you, directly, how old the universe is, because it's showing you exactly how far the delivery has gotten so far.

Think of it as the single largest delayed delivery in history, 13.8 billion years and counting, running late since the actual beginning of actual everything. If Deutsche Bahn ran this route they'd put it down to "Verspätung aus vorheriger Fahrt" and leave it there.

Go back outside for a second and actually look. That blackness between the stars is doing exactly what it's supposed to.

You're not looking at now

Follow that thought one step further and it gets worse. Light isn't instant, which means nothing you see in the sky is happening right now. You're always looking at the past, and the further away the thing is, the further back you're looking.

Sunlight takes about 8 minutes to reach Earth, so you are, technically, always looking at the sun as it was 8 minutes ago. Sirius, one of the brightest stars in the sky, is about 8 and a half light-years away, so that's 8 and a half years of lag. Betelgeuse, the red supergiant in Orion that's near the end of its life and expected to go supernova at some point, soon on an astronomical timescale, meaning possibly tomorrow, possibly in 100,000 years, sits around 550 light-years out. If it already exploded sometime in the last five centuries, the light telling us that hasn't arrived yet. It could already be gone. We would have no way of knowing until the news physically gets here.

Zoom out further and the lag gets absurd. The Andromeda galaxy, the nearest big galaxy to ours, is 2.5 million light-years away. Every photo of it is a photo of how it looked 2.5 million years ago, before humans existed in anything like our current form. There is no version of looking at Andromeda "as it is now." That sentence doesn't mean anything. Now, for Andromeda, is unreachable, permanently hidden behind a 2.5-million-year delay that never shrinks.

Whatever you're looking at tonight, it already happened. Next clear night, remember that at least a few of those points of light might already be gone.

The places we will never reach

Here's the part that isn't just delayed, it's actually impossible, and not because we're not clever enough yet.

Space itself is expanding. Not things moving through space, the space in between things is stretching, everywhere, all the time, and it's been accelerating. The further away a galaxy is, the faster the space between us and it is stretching, which means its apparent recession speed increases with distance. Past a certain distance, that stretching adds up to faster than light, even though nothing is actually moving through space faster than light. The space itself is just growing quickly enough to outrun it.

That distance has a name: the cosmic event horizon. Light from anything beyond it can set off toward us right now and never arrive, not in a billion years, not ever, because the gap it needs to cross is growing faster than the light can close it. It isn't a question of better telescopes or faster ships. The problem isn't speed. It's that the finish line is receding faster than anyone could run toward it, forever.

This is also why the observable universe is about 93 billion light-years across, even though the universe is only 13.8 billion years old. Those numbers look like they contradict each other until you remember that the space the light has been travelling through has itself been stretching the whole time it was in transit. The light has had 13.8 billion years to travel, but the distance it crossed kept growing underneath it while it moved.

And it keeps getting worse going forward. Because the expansion is accelerating, galaxies we can see perfectly well tonight will, over tens of billions of years, cross that horizon and quietly vanish from what's reachable, not by moving away in any dramatic sense, just by the space between us stretching past the point where their light can still complete the trip. Whole galaxies, currently visible, are on a one-way trip out of contact, and there is nothing anyone could build to stop it.

Before the beginning

If this is starting to read like homework, I promise it isn't, there's no test. There's also, as it turns out, no clean answer either, which might honestly be worse.

Here's the one nobody has an answer to, not really: what was there before the Big Bang?

The honest answer is that the question might not even be a legal one to ask. The Big Bang isn't really an explosion that happened at some location inside a pre-existing space, it's the start of space and time themselves, as far as general relativity can describe it. If time itself began there, "before" doesn't point at anything, there's no earlier moment for anything to have been in. It's less like asking what's north of the North Pole, and more like asking what's north of a direction that doesn't exist yet.

Physics can trace things back with real confidence to about a tiny fraction of a second after that beginning, roughly 10^-43 seconds in, a point called the Planck epoch. Before that, gravity and quantum mechanics stop agreeing with each other, and nobody has a working theory for what the universe was actually doing. There are real, serious proposals, universes bouncing endlessly between collapse and rebirth, inflation branching off into other universes we could never reach or detect, but all of them are currently unprovable. Not wrong, necessarily. Untestable. Which, for the first time in this whole post, means physics genuinely doesn't know, and might not ever be able to know.

I'll just say where I land on this, because pretending not to would be weird. I'm Catholic. When physics hits a wall and says it genuinely doesn't know what caused any of this, I already have an answer, and it's God. I can't prove that to you, and I'm not going to pretend any of the physics in this post backs it up, because it doesn't. But I'd rather believe something had a reason behind it than believe it was an infinite stack of universes nobody will ever see, which, if you think about it, takes just as much faith anyway.

That's where I land. It doesn't make the not-knowing part any less strange to sit with.

Needing a cause for everything, and sometimes there isn't one, not one we can get to anyway. There's a line that's stuck with me for a while now: the human obsession with purpose is merely a distraction from the absurdity of existence. It's a brutal way of putting it, but it tracks. We build origin stories for the universe because an unexplained beginning feels unbearable, and most of us do the same thing with our own lives, backfilling a reason for everything that happened to us, because "it just happened, there wasn't a reason" is somehow worse to sit with than almost any actual answer.

I'll say the real version of that plainly, because dressing it up wouldn't be honest. I haven't done anything in six years. I lost the thread of what I was even trying to build. I don't have a clean cause-and-effect story for how I got from where I thought I was going to exactly here, and looking for one has mostly just kept me stuck looking. Maybe there isn't one. Maybe, like the universe's own beginning, some things don't have a "before" that explains them. They just start, and the only real question left is what happens next.

The universe could end right now, with no warning at all

One more, and this one isn't about distance.

The vacuum of space, the "nothing" between everything, might not actually be empty in the sense of being the lowest-energy state it could possibly be in. Based on the measured mass of the Higgs boson and the top quark, calculations from the Standard Model suggest our universe might currently be sitting in a false vacuum, a false floor, stable enough to last a very long time, but not the actual bottom.

If that's right, then somewhere, at some random point, a bubble of the real, lower-energy vacuum could spontaneously form through quantum tunnelling, for no reason, with no trigger and no cause. Once it exists, it expands at close to the speed of light in every direction, converting the physics inside it, the masses of particles, the strength of the forces holding atoms together, into whatever the true vacuum's version of those rules is. Anything the bubble wall touches stops working the way it currently works. There's no surviving it and no outrunning it, because it's moving almost exactly as fast as any warning about it could possibly travel.

The honest caveat: if this is even possible, every calculation says it's wildly unlikely to happen any time soon, where "soon" is measured in timescales vastly longer than the current age of the universe. This isn't "don't worry, go outside tomorrow" levels of safe, it's genuinely that unlikely. But "unlikely before an unimaginably long time has passed" is a different thing from "cannot happen," and if it ever does happen, there is categorically no warning, no sign, and nothing anyone, anywhere, could have done differently.

If you want a smaller, weekly-recurring preview of something collapsing with zero warning and no way to stop it, I have, unfortunately, been watching Spurs this season.

Nobody's grading you

Here's the part that flips all of this from dread into something closer to relief, if you let it.

If the sky is this old, this empty, this indifferent to whether you ever looked up at it, then the universe was never grading you. Nothing about any of this cares whether you built the thing you planned to build by the deadline you set for yourself. Nothing about any of this even knows your name. We are a tiny speck of dust, floating in a galaxy so large the scale stops meaning anything useful to a human brain, inside a universe that, as covered above, might not even remember how it started.

That sounds like it should make everything feel smaller and worse. For me it's mostly done the opposite. A lot of the pressure I've been carrying wasn't ever handed to me by anything real, it was self-issued, a deadline I set against a universe that was never watching the clock. Some of it wasn't even mine to begin with. I was handed false hope on a loop for longer than I'd like to admit, told the ground was solid every time right before it gave way again, and the universe's vacuum, for all its talk, never once pulled that stunt on me. None of this is permission to stop caring about anything, it's the opposite of that. If nothing out there is going to notice or protect what's good around you, that's exactly why it's on you to. Don't let anything ruin what's right in front of you, the people, the ordinary good days, just because some version of you from a few years ago had a bigger plan that didn't happen on schedule. The universe was never going to hold you to it. You don't have to either.

I'm not all the way back from any of that yet. But slowly, something that looks a lot like normal is starting to come back, and I'm done waiting for someone else's floor to hold.

On Saturday, that theory got tested almost immediately. Spurs drew 1-1 with United, abysmal reffing, the same problems as a few weeks ago, a lucky Solanke goal keeping it level. We move.

Turns out you didn't need 13.8 billion years of cosmic dread for this. Ninety minutes of Spurs will do it.