The universe, as far as scientists know as of today, is expanding. It's expansion is becoming faster over time. My everyday life is, of course, not at all impacted by this; nonetheless, I occasionally find myself experiencing a tinge of sadness knowing that our isolation as intelligent beings in the universe grows more complete by the day. Perhaps there is other intelligent life, at this moment, attempting to make its way towards us, but because we are hurtling away at speeds they cannot even hope to achieve, because we are being thrown deeper into deep space, they will never find us.

I thought about this, frankly, mostly fictional scenario rarely. Perhaps when something about space came in the news, or when I looked up to see a particularly brilliant night sky studded with starlight, I would feel that familiar tug at my heart, but that has changed. Over the last few years, I have found myself thinking about our little (actually it's quite large) green and blue spaceship and the vast, cold, impenetrable space it sits within more and more frequently. I didn't, initially, understand why the universe's expansion was becoming so troubling to me exactly at that moment, but I think I do now.

Interpersonal Space and the Interpersonal Medium

When's the last time you sent a letter? To clarify, when is the last time you wrote out a page or so of your thoughts in your own handwriting, folded the page into thirds (probably incorrectly the first time), placed the paper into an envelope, placed a stamp on it, wrote out the address of the person you sent it to in the middle of the envelope, wrote out your own address in the upper left hand corner, and then either placed it into your mailbox, or gave it to a mailman, or went to the post office yourself to send it through the post? When is the last time you waited for days to receive a letter back? When was your prose last written in your own handwriting for just one single person's eyes to see?

Honestly, I can't remember the last time I sent a letter like that. I think I did, when I was a child at some point, but that process had already become antiquated. I don't think I've ever waited for a letter. Some people may soak that experience in a nostalgic bath, lamenting that waiting for that letter was somehow virtuous, a virtue that "people these days" lack. In truth, writing out your thoughts to another person in that form, knowing that they wouldn't receive it for days, sometimes weeks, sometimes months, was hard. Yearning for a response for days more, weeks more, sometimes months more, was hard. We have always dreamt of faster ways of communicating. Our gods, thousands of years old, deliver the good news; our demons whisper seductive knowledge in our ears.

The space in between solar systems that is influenced by no particular star is interstellar space. The distance between the Sun and the nearest other star, the shortest stretch of interstellar space that surrounds the sun, is about 4.8 light-years. That is an incomprehensibly large distance. There is no single comparison, in my opinion, to be able to understand how gargantuan a single light-year is, much less five of them. One hypothetical day, though, our descendants may find themselves wanting to travel this distance, and perhaps have some kind of craft that can make the journey at speed. Thankfully for them, the interstellar medium, the matter that occupies interstellar space is remarkably sparse. Single hydrogen atoms and the occasional helium atom will pass them by as they make their way to Proxima Centauri, our stellar neighbor.

In order to communicate, we must wait, and we must hope. Any message is sent through a route, and whether an in-transit message is on a road, on a plane, in the wire, on radio waves, or anything else, that route is where the sender and the recipient both lose control over the fate of the message. Like the space between the influence of stars is called interstellar space, the space in between the influence of participants in communication is interpersonal space.

Unlike largely empty interstellar space, however, interpersonal space is very, very full of the interpersonal medium. The interpersonal medium is the collection of all the factors along the route that make a message less likely to be delivered intact, or at all. A letter from me to my friend across the ocean may pass through interpersonal space on trucks, trains, ships, or planes, but it encounters resistance from the interpersonal medium all along the way. The letter may fall off a vehicle, or it may be seized at customs. It may be delivered to the wrong address, or it may be lost in a port somewhere. It may be torn up into little pieces, causing my friend to receive a meaningless pile of scraps that used to be my letter.

In the past half-century we have made massive strides in humanity's ability to traverse interpersonal space at speed, and simultaneously we have made the interpersonal medium much, much thinner than it was. The infrastructure that has been laid over decades enables messages to travel across the world cheaply in milliseconds--the trans-Atlantic cables that connect the world, the network interchange infrastructure in the USA that routes traffic to and from international destinations, the cables that provide high-speed internet to a still-too-small proportion of Americans, and the cell towers that blanket the landscape in connectivity are all part of interpersonal space. It has become much, much, much faster to travel through interpersonal space than it used to be. I think this is good, on the whole.

The interpersonal medium had also been becoming thinner and easier to pass through in the past several decades. RSA encryption, invented in 1983 and released into the public domain in 2000, allowed messages to pass between two endpoints without risk of eavesdropping, even if those two endpoints had never made prior contact. E-mail, chatrooms, and forums made it easier than ever to find a desired recipient and to contact them. Google revolutionized searching, allowing anyone to interpret the massive web of links that the internet had become. Even early social media was built on the promise of connecting the world, enabling messages to pass through to their recipients with fewer barriers than ever before. Before 2023, the interpersonal medium had been continuously thinning, becoming easier and easier to pass through. Messages were able to be passed to any recipient that cared to listen.

Something changed, obviously. Large language models made it possible to create relatively convincing human simulacra. I'm not here to argue whether or not LLM-generated content is or is not from human-created content. It's clear to me that, regardless of the differences that do exist in the output of people and the output of LLMs,