It Happened Where You Are Sitting

Almost everyone carries the same image, and almost nobody was told it was an approximation. A point. Empty blackness around it. Then a flash, and debris flying outward into the waiting dark.

It is a good picture. It is vivid, it is easy to draw, and it is wrong in a specific and checkable way — not blurry, not simplified, but describing a different thing from the one the theory describes.

Three assumptions are smuggled in with it, and each one is doing damage:

That there was already space, sitting there empty, waiting. That there was a place where it happened, which you could in principle travel to. And therefore that there is a centre — and if there is a centre, everything else has a distance from it.

The picture is not a simplification of the theory. It is a different theory, and nobody is teaching it.

The last of those three is the one this zine is about, because a centre is never only a fact about geometry. A centre is a licence to sort things by how far they are from it.

In 1929 Edwin Hubble published six pages in the Proceedings of the National Academy of Sciences reporting that the more distant a galaxy is, the faster it is receding from us.

Read that through the picture on the last spread and it says something alarming: everything is running away from us specifically, so we must be at or near the place it started.

Read it through the geometry and it says the opposite. If every separation grows by the same factor, then from every vantage point the distant things recede fastest — not because you are central, but because there is more stretching distance between you and them. The observation that looks like evidence of a centre is the signature of there being none.

This is the bread-and-raisins analogy, and it is worth naming the flaw rather than repeating it and hoping. A loaf has a crust. It has an outside, an edge, and a raisin nearest that edge. The stretching is right; the container is not, and the container is precisely the thing in dispute.

Every raisin sees itself as still, and every other raisin leaving. All of them are right, and the loaf is the part of the analogy to throw away.

The most common follow-up question is what is it expanding into? — and the honest answer is not a fact but a correction: the question has a container built into its grammar, and the theory has no container to offer it.

“Into” presupposes a somewhere-else. Expansion here does not mean a thing getting bigger relative to its surroundings. It means the distances between things increasing, measured by rulers that are themselves inside the thing being described. There is no outside vantage from which the universe could be seen to occupy more room than it did.

This is not a dodge and it is not new. It falls directly out of the solutions Alexander Friedmann published in 1922 and Georges Lemaître published independently in 1927, which describe the whole of space evolving in time without ever positing an edge for it to press against, or an exterior for it to press into.

What this does not settle. Whether space is infinite or merely unbounded-and-finite is a separate question, still open, and spread eight is about how open it actually is. Neither answer supplies an outside, and neither supplies a centre.

Once there is no container and no edge, the question where stops having the shape it looked like it had. The hot dense phase was not an event that occurred at a location. It was a condition of all of space at once.

Every region that exists now existed then, packed unrecognisably closer together and far too hot for atoms to hold. That includes the region you are in. The volume your body currently occupies was part of it. Not descended from it, not made of material that travelled from it — it was it, at a different density and temperature.

So the Big Bang did not happen somewhere else and send you the leftovers. It happened here. It also happened in the Andromeda galaxy, and in the space between your hands, and at every other position you could name, because those positions are what was hot.

It is not that you are made of the debris of a distant event. You are standing in the place where it happened. So is everyone.

And here is the consequence the rest of this zine is about. If it happened at every location, no location is the origin. If no location is the origin, there is no distance-from-origin. The geometry declines to tell you who is near the middle, because it has not got one.

There is one centre in all of this, and refusing to mention it would be the kind of tidy half-truth this collection exists to argue against.

Light travels at a finite speed and the universe has a finite age, so from where you are you can only see out to the distance light has had time to cross. That region is your observable universe, and it is a sphere, and you are exactly at the middle of it. Not approximately. Exactly.

Its radius is set by an age that has been measured: the Planck collaboration’s 2018 analysis gives 13.797 ± 0.023 billion years, combining the microwave background with baryon acoustic oscillations.

Now the part that matters. Everyone has one. A person in Andromeda has a sphere of their own, the same size, centred on them, overlapping yours and extending past it in the opposite direction. There is no arbitration between you. You are both exactly central, and neither of you is central to anything but your own sphere.

Every observer is at the centre of their own observable universe, and every one of them is right.

That sentence is harder than the flattering version. It does not say you are the centre. It says the centre is a fact about where you are standing, not about what is standing there — and that it is generated fresh for every observer, at no cost, without taking anything from anyone else.

There is a cheap reading of everything above, and it needs killing here rather than in the refusals at the back, because the rest of the zine leans on its absence.

The cheap reading is: no centre, therefore no reference, therefore nothing can be measured against anything, therefore it is all just perspective. That does not follow, and cosmology has the counterexample lying in plain sight.

The microwave background is not quite the same temperature in every direction. One half of the sky is very slightly warmer and the opposite half very slightly cooler — a dipole — and the reason is motion. We are moving, and the light ahead of us is shifted accordingly.

That gives a frame in which the dipole vanishes, and every observer anywhere can find their own motion relative to it. Planck measured the Solar System’s at 369.82 ± 0.11 kilometres per second. It is one of the best-determined numbers in the subject.

There is no privileged place, and there is still a shared reference every observer can measure against. Those are different claims, and only one of them is being made.

So: no centre does not mean no ground. It means the ground is something everyone can check independently and agree on, rather than something one position gets to declare on behalf of the rest.

Every popular account reaches the same confident sentence: the universe is flat, and therefore probably infinite. Both halves need unpacking, and the first one does not mean what the word suggests.

Flat is not a claim about thinness. It is a claim about the geometry of space itself — whether Euclid’s rules hold over cosmological distances. In flat space parallel lines stay parallel, the angles of a triangle sum to 180 degrees, and the volume inside a sphere of radius r grows as r³. In positively curved space — the three-dimensional counterpart of a ball’s surface — parallels converge, triangles come out fat, and space closes on itself, so it is finite. Negatively curved space does the opposite and is open.

So is it flat? means which of those three do we live in? — and it is answered by checking triangles on the largest one available: the hot and cold patches in the microwave background, whose true size the theory predicts, measured against how big they look.

The sign convention catches people out. The measured quantity is written Ω_K, and it runs opposite to the curvature itself. Zero is flat. Negative means positively curved, closed and finite. Positive means open. So a paper reporting “positive curvature” and a table reporting a negative Ω_K are describing the same universe.

Now the measurement, which is really three measurements, because every dataset you add pulls it closer to flat:

Planck’s temperature and polarisation spectra alone give −0.044, with a 99 per cent range running from −0.095 to −0.007 — the paper notes that only about one sample in ten thousand lands at zero or above. Add the lensing map and it moves to −0.0106 ± 0.0065. Add the baryon acoustic oscillations and it lands on 0.0007 ± 0.0019 — flat, comfortably.

Planck’s own explanation is mechanical rather than rhetorical: the microwave background alone suffers a geometric degeneracy that lensing partly breaks, and closed models predict more lensing than we see.

But this is not a settled matter with one awkward number in it. Di Valentino, Melchiorri and Silk published the other reading in Nature Astronomy in 2019, arguing the Planck spectra prefer positive curvature at better than 99 per cent confidence and that assuming flatness “could therefore mask a cosmological crisis.”

The argument is live, in the literature, between named people. That is what an open question looks like from the inside.

Here is why any of this is in this zine. The no-centre claim survives every branch of that disagreement. An infinite flat space has no centre. A finite closed space has no centre either — the surface of a ball is finite, unbounded, and has no middle anywhere on it. Infinity was never what was doing the work.

Six spreads ago we wrote that space itself expands, and we have leaned on it since. It is how the subject is taught, it is how every textbook phrases it, and it is not a finding.

It is a picture — a way of holding the mathematics that most people find tractable. And there are cosmologists who think it is a bad one, on the grounds that it invites exactly the reification this zine spent spread four dismantling: space as a material that stretches, doing things to the galaxies sitting in it.

Emory Bunn and David Hogg made the case directly in the American Journal of Physics in 2009, arguing that the cosmological redshift admits a perfectly good kinematic reading — light from a receding source, Doppler-shifted — and that the expanding-space story is a choice of description rather than a physical mechanism that has been detected.

What that does and does not touch. It is an argument about how best to describe the geometry, not about whether the geometry is right. The distances grow either way; the measurements are unaffected; and nothing in the dispute reinstates a centre. We keep the expanding-space language because it is the shared vocabulary, and we are flagging it because using a field’s standard picture without saying it is a picture is how the popular account on spread two got made.

We told you the wrong picture was being handed on unmarked. The least we owe you is the label on ours.

One more, smaller: the whole no centre result rests on the assumption that no place in the universe is special — the assumption Friedmann and Lemaître wrote into the solutions from the start. It is strongly supported by how uniform the sky looks at large scales. It is still an assumption, and it is doing real work here.

This zine has now described the same structure three times without naming it. Naming it is the turn.

The raisin, on spread three. Every raisin sees itself as still and every other raisin leaving, and all of them are right. We kept the stretching and threw away the loaf, because the crust was the only part that could have told you which raisin was central.

The sphere, on spread six. Every observer sits exactly at the middle of their own observable universe. Not approximately. And it is generated fresh for each one, at no cost, taking nothing from anybody else.

And a third, which is neither ours nor physics. Helen Edgar’s constellation of intensities — carried on from Patrick Dwyer’s autism constellation, and older than either, as Not a Line records in detail. A constellation has no baseline and no rank; its stars sit at wildly different distances and cohere into a figure only from where you happen to stand.

Read those together and the shape is unmistakable. In all three, the coherence is made at the vantage point. It is not a property of the thing being looked at.

The figure is real. It is also made where you are standing — which is why nobody standing somewhere else owes you their coordinates.

So here is normative centering, stated exactly. It is the error of taking one vantage point’s figure and installing it inside the object as an origin — and then measuring everyone by their distance from it. High-functioning. Mild. Severe. The far end of the spectrum. Each of those is a distance, and none of them will say whose vantage point supplied the zero.

But the three are not equivalent, and flattening them would be the mistake this whole piece is built to avoid. The raisin and the sphere are physics. Nobody chose them, nobody installed them, and nobody can un-install them. The constellation is a figure that Autistic people chose, deliberately, against one that had already been installed in them.

Which is the whole and only use of the cosmology here. It is not the argument — it is the existence proof. A complete, predictive, relentlessly tested description of everything there is turns out not to need a centre, and loses nothing by not having one. That is sufficient to answer the one claim normative centering has always rested on: that a middle is compulsory.

Where this stops. Not a Line (No. 21) is the piece that makes the constellation argument properly, with the functioning-label critique and the lineage the metaphor belongs to. This spread does not re-run it. It only shows that the cosmology had been the same shape the whole way down.

A piece that moves from cosmology to people has about four ways to go wrong, and three of them are flattering. So, plainly: