Cosmological Inconstant

It was around 60° the other day and I went running over the lunch hour. This was in late February in Missouri, totally unexpected and delightful weather that I was glad to take advantage of. As happens to me more often now, I remember what I was doing when I heard a particular podcast, much the way I used to remember what I was doing when I listened to a popular song. This day, while running along the narrow road and feeling the feeble winter sun warm my back, I heard a story that sent me into a nice little contemplative daydream for several minutes.

Scientific American has a podcast called 60 Second Science. It's on the web at http://www.sciam.com/podcast/ (not to be confused with Science Talk, another excellent podcast). Also the extended Scientific American Podcast for that day had an extended interview detailing the same point.

The February 18th 2009 podcast featured Chicago's annual meeting of the American Association for the Advancement of Science (AAAS). On Monday February 16 they had a press conference featuring cosmologists Alan Guth from M.I.T. (developer of the inflationary model of the universe), Arizona State University's Lawrence Krauss, John Carlstrom from the University of Chicago (an expert on the Cosmic Microwave Background Radiation), and Fermilab's Scott Dodelson (an expert on the structure of the universe).

They were discussing the state of cosmology and the universe's possible "dismal" future. They believe that all of the indicators of the Big Bang will disappear. The evidence for the Hubble expansion will disappear when the galaxies that we use to trace it disappear. Even the Cosmic Microwave Background Radiation will eventually go away.

Article said that a cosmologist in the far future would not be able to figure out the big bang, and that the only evidence he had left to go on would indicate that the Universe was static and eternal, just like what recent Cosmologists thought up to around 1900.

So we will look at the universe in the far future (50 billion years from now compared to the current 13.7 billion year age of the universe) like what the ancient philosophers used to think of the universe. They thought that the heavens were fixed, unchanging, and eternal.

I'm not a cosmologist, but I love listening to them. I read Stephen Hawkings' A Brief History of Time, and understood the general concept. We theorize that all matter filled a single point, called a Singularity, at the beginning of the universe, and it exploded into existence, all at once. I remember thinking at the time, what was before that? Where did the Universe come from? The physicists' answer is that we don't know that, we can't know that, because the singularity that was the birth of the universe, by definition, means that you cannot know what was before it, all evidence was destroyed. This made me visualize the universe as a two stroke engine, exploding into existence, collapsing back down into a point, and exploding anew. Because I can't imagine that there was nothing and suddenly there was something, and that's no what they are saying about the Big Bang. They aren't saying there was nothing before it, they're saying we can't know what was before it.

Modern cosmologists calculated the size of the universe, then theorized the big bang from seeing traces of that explosion and older galaxies whose light is just now reaching us. They tell us that the universe has some kind of strange dimensional quality where if you could point a spaceship in some direction and take off incredibly fast, that you would eventually come back to where you started. They compare it to the way you could start somewhere on the earth and take off in one direction (let's say in a plane whose course is unaffected by wind currents) that you will eventually come back to where you started. That makes sense when you think of it as something moving along the surface of a sphere. The observer in the plane thinks he's going along a flat surface and suddenly he's back where he started from. Well, space is supposed to be like this, but not because it's a sphere, but because of some trick of spacetime. I read about it and I can't properly explain the shape or condition that makes this so, but it's a generally accepted idea.

The other thing that blows my mind is the thought that we can see things that are almost as old as the universe, because the light from them is just now reaching us. Does that mean it was flying away from us slightly slower than the speed of light, and the light was barely creeping toward us? Not according to Einstein, who says that light is constant and time is the variable. These are concepts that make the layman give up on figuring out Cosmology and why it seems to be the playground of geniuses and off limits to the average person.

There's only a small percentage of people in the world that can comprehend this field, and an even smaller portion of them that are figuring out the basics of cosmological reality. The worst part is that they know that they don't understand it very well, and they understand some of what it is they don't understand, they've got the right questions, but no answers. You hear a lot of physicists and cosmologists talk about Dark Matter and Dark Energy. They admit that they don't understand what this is. What they rarely explain to the rest of the world that is ignorant of the finer points of their work, but eager for them to work it out, is that these unknowns are just imaginary numbers. It's like Algebra. When you don't know a quantity, you just assign it an arbitrary label, usually x. X just means "the unknown quantity that I am trying to figure out". Which is exactly what Dark Energy and Dark Matter are. They measured the universe and their numbers came in way off. We can't account for over 95% of the matter or energy in the universe. We think it's there based on what we see it doing to the matter in the galaxies, but we can't see it, thus Dark Matter. It's almost like a boogey man or a spirit. Maybe it's the invisible hand of God (did you ever think of that, Mr. Scientist? I didn't think so!).

In any case, we sneer at the "scientists" of the past (up to around 1900) that thought that the universe was fixed and unchanging. How little they understood. Then, with sophisticated new tools, we looked out with some precision and made some measurements and Wow! These stars are all moving, and Hey! some of those points of light aren't distant stars, but whole galaxies.

If scientists in the future aren't going to be able to figure it out (with the tools we have now) how do we know we have enough clues to figure it out? Maybe that's what Dark Matter and Dark Energy are, maybe they are the remnants of something that used to be obvious or visible, and is now just some shadow of an effect that we think we understand. Maybe we are 60 billion years old and it just looks like the way things are now because the light is just now reaching us.

If we can theorize a time when evidence we now have will be gone, what evidence that used to be there is gone now? What do we not know that we don't know? What can we not figure out based on what we see? If this is the case, that we can't know certain things, then can't you say that any theory is possible? Where does it end?