“Imagine yourself waking up in a strange and unfamiliar room. Too much to drink maybe, some medical crisis, who knows … there you are. To compound your difficulties, you have amnesia, and can’t for the life of you remember anything about your life before you awoke in the room. It’s a normal enough looking room as far as you can tell, reasonably furnished, but with no sign of its purpose, or why you happen to be there.
You get up to explore. The room has doors, four of them, one on each wall. Upon inspection, each door leads to a featureless hallway, with a door at the other end. Well, there’s no choice but but head down a hallway. At the end of the hallway, there is another room. Upon inspection it’s the same size as the first room, but furnished differently. It too has four doors. And each door leads to a hallway. You continue on. Through another hallway. To another room.
And another, and another, and another. Room after room after room. Each room similar, but no two alike. Your needs are met at least, many of the rooms have the means to support life, food, water, etc. Even to make life pleasant, some rooms are quite enjoyable. You sometimes linger awhile, days or weeks, but eventually you head on, looking for a door outside or even a window. On and on and on.
It gets worse. Eventually you are sure you have sometimes come back to a room where you’ve been before. You test your theory, you head off in a straight direction, always exiting the opposite door you entered by. Finally, after traversing seemingly endless rooms, you notice that at least one thing has changed, the hallways are getting longer. Eventually, you open a door … and are back in the very first room you started from so many years ago.
Unquestionably the same room, unchanged in any respect except for dust. And the hallways leading from it are longer than they were those long years ago. Years of exploring, years of pondering, and it still doesn’t make any sense. And yet, it is what it is. What the hell is going on here?”
What is going on here? I wrote the above because I kept seeing people in Yahoo Answers ask the question “If the universe is expanding, what is it expanding into?” This means that a lot of people are unclear on exactly what is meant by the “expanding” universe. Even worse, a lot of the answers to the question were gibberish or so technical as to be effectively gibberish. And a lot of the analogies people came up with to explain the universe weren’t as helpful as the authors might have supposed. A wise woman (no, she wasn’t a Latina) once said to me that if you can’t explain something to a five year old, you probably don’t understand it yourself. A test I no doubt fail on many an occasion, but I keep trying.
In any event, the above analogy is the universe as we know it. An enormous (but not infinite) number of rooms slowly getting further apart, with never a door or window to anything else. Think of the rooms as galaxies if one wants, as far as our best and brightest can currently tell, our universe is just like my hypothetical nest of rooms. It doesn’t have an edge, there are no boundaries, there is no way out. And the distance between every point in the universe is getting greater, but nothing new is being added. And of course it doesn’t make sense, if I am getting to any sort of point with this post it’s that what scientists observe about the universe isn’t subject to our notions of what “makes sense.” It’s reality that makes sense, not our conception of it.
I know what I would wonder if I found myself in the above situation. I’d wonder who made the rooms. It wouldn’t be a crazy thing to wonder, would it?
Have a great weekend everyone.
(The above image is being used in accordance with the copyright holder’s requirements. It is not being used for profit. Attribution: http://www.flickr.com/photos/leted/ / CC BY-NC 2.0 It’s a hallway, what else can I say? I thought it was a good image to illustrate the post with. “Every exit is an entrance somewhere else.” — Tom Stoppard.)