h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

The theory of there being an infinite number of timelines is string theory, specifically the theory of the eleventh dimension - a 'multiverse' containing an infinite number of universes (universi?) each with a different law of physics and therefore a different timeline

Sub-atomic particles are what led scientists to believe this theory. They are particles that are never in the same place twice and often are in two places at the same time. This gave said sceintists the idea that the particle may be flitting (sliding?) between different universes.

Using the example of the Earth moving around the sun, the first three dimensions map out the coordinates of the Earth relative to the Sun. The fourth dimension - Time - is a coordinate that changes when objects move. Therefore time is movement. But what causes this movement? The gravity of the sun causes us to move relative to the Sun but we are also moving relative to the centre of the galaxy. The Big Bang expansion theory states that the universe is rushing away from [something] so we are also moving relative to that. But perhaps it is all about gravity. Maybe we are not rushing away from a point but towards another point. Alternatively we could be rushing away from a point because there is a huge negative-gravity force pushing us from there.
I think we should replace time with gravity as the fourth dimension

There you go. Amazing what you can do with an over-active imagination and not much scientific knowledge.

The universe is not rushing from point a to b. It is expanding.

And did you know that time slows down in a strong gravitational field?

That was the very comment I was about to make, except that time slows down to some degree in *all* gravitational fields; it's just more detectable with strong ones. Oh, and it runs at a different rate on a moving object compared to a stationary one. Except that there are no really ststionary objects - it's all relative. Oh damn, now my too...

ststionary - stationary

What, like pens, and paper clips and stuff

That's "Stationery"

Phew, that's cleared that up. I was staring to get confused as to what difference a biro could make to the nature of the space-time continuum (is that still curved?)

Yup. Although, to a paper clip in orbit around a box of copier paper in an otherwise closed system the paper would appear, relatively speaking, to be stationary stationery...

Hmm, isn't it possible that time slows down in the presence of stationery? That is why a day at the office can feel so long.

Now I'm rather confused.

I should bring back some good material to discuss about chaos theory on Monday or Tuesday. Till then,

Mmmmm, chaos theory. I can't decide whether or not I like it. I like the idea that everything is affected by everything else on a very small level of organization, but my line of reasoning carries it out farther. It's my belief that since every action has a cause, and since every cause is an action, which has a cause (and so on) that *everything*--including my typing this post and my buying of a Dilbert calendar--is predetermined at a molecular (or smaller!) level. This doesn't explain what the *first* action that started the chain was, or whether the chain is a loop of links--bringing us back to the time theme. This is something I'm trying to work around.
Another thing that comes with this is free will. Does this model allow for free will or just its illusion? Personally, I think it's the illusion.

Gaaa....
I'm so very glad I have the Guide to put these opinions out on.

~Wes

The principle of chaos theory is this:

You have 30 particles in a system. You know the starting position and velocity for each particle. Therefore, you should be able to predict everything about the system for the rest of its existence. This is where chaos comes in. The predictions are good for a while, and then they start going wrong. At 10 time units, the system is still fairly stable, with everything going as predicted. However, after 20 time units, everything is all messed up, with particles scattered all over the place. Why? Chaos. I have a bunch of handouts illustrating this which I can show you some time, Ex Libris.

The simplest expression of Chaos theory was something I heard on the radio this morning. In a nutshell:

"The predictability of a system is in no way related to the simplicity or otherwise of the equations governing it."

That's pretty much it. I don't have a good explination of why it works that way, only that it does. And it makes some really cool 3d graphs. Perhaps if you looked for the Lorentz equations, or plots thereof, you could find some good examples.

I guess one simple analogy might be a pinball machine - even if you knew extremely accurately how the bumpers behaved, and the initial speed and direction of the ball at the start, knowing what will happen to the ball after a few bounces gets very difficult, even before it gets hit by the flippers.

That too. Any occurence can have unpredictable effects on the whole system, perhaps even if the occurence isn't within the system.

Does anyone know the American TV drama, CSI?(Crime Scene Investigation) An episode we saw last week, laid a woman's death to a series of individually improbable accidents, and cited chaos theory! Very deep.

That sounds kind of like the butterfly flapping its wings in China, and causing a hurricane because of it.

Either Bruce Sterling or Spider RObinson wrote a story about this. It's called Madmae Butterfly, and is in either "A Good Old-Fashioned Future" or "User Friendly." I think its in the Sterling, but am not positive.

And from a couple posts ago, those should be the Lorenz equations. There's no T in there.