The Random Comic Strip

The Random Comic Strip

Words to live by...

"How beautiful it is to do nothing, and to rest afterward."

[Spanish Proverb]

Ius luxuriae publice datum est

(The right to looseness has been officially given)

"Everyone carries a part of society on his shoulders," wrote Ludwig von Mises, "no one is relieved of his share of responsibility by others. And no one can find a safe way for himself if society is sweeping towards destruction. Therefore everyone, in his own interest, must thrust himself vigorously into the intellectual battle."

Apparently, the crossword puzzle that disappeared from the blog, came back.


Tuesday, November 9, 2010

Time for thought


Now the time has come (Time)
There are things to realize (Time)
Time has come today (Time)
Time has come today (Time)


I recently read an article about time in the Huffington Post. Now, I don't agree with much of what is written in the Huffington Post but this article was interesting. It was interesting because time is interesting.

For instance, does time pass? Or do we move through time? What is time? We can measure it but is it real? It is certainly a component of the dimension in which we live. I consider us to be in a four dimensional universe: length, width, depth, time (or, in shorthand, "time (1) and space (3)"). I could be wrong, I am not a physicist. I have never even played one on TV or anywhere else.

There is a question one asks of a stoned person. If one is not too stoned oneself. It's a simple question, see if you can answer it...

Where is the person when he jumps off the ledge?

If you answer "on the ledge", it is wrong. That is before he jumped. If you answer, in the air, it is wrong. That is after he jumped. You see, at the instant that he jumps, he does not exist in time as we know it.

An ancient Greek, Zeno, talked about an arrow in flight.

The arrow paradox
“ If everything when it occupies an equal space is at rest, and if that which is in locomotion is always occupying such a space at any moment, the flying arrow is therefore motionless.”
—Aristotle, Physics VI:9, 239b5

In the arrow paradox (also known as the fletcher's paradox), Zeno states that for motion to occur, an object must change the position which it occupies. He gives an example of an arrow in flight. He states that in any one instant of time, for the arrow to be moving it must either move to where it is, or it must move to where it is not. However, it cannot move to where it is not, because this is a single instant, and it cannot move to where it is because it is already there. In other words, in any instant of time there is no motion occurring, because an instant is a snapshot. Therefore, if it cannot move in a single instant it cannot move in any instant, making any motion impossible.

Whereas the first two paradoxes presented divide space, this paradox starts by dividing time—and not into segments, but into points.[11]

http://en.wikipedia.org/wiki/Zeno%27s_paradoxes#The_arrow_paradox

(Yes, it seems to me it should be called "Aristotle's Arrow Paradox", too)

That aforementioned Huffington Post article explains it this way:

Because an object can't occupy two places simultaneously, he contended that an arrow is only at one place during any given instant of its flight. To be in one place, however, is to be at rest. The arrow must therefore be at rest at every instant of its flight. Thus, motion is impossible.

In many ways, this reminds me of the myth1 of the bumblebee's flight. According to the myth, the bumblebee is incapable of flight. This does not bother the bumblebee, who knows nothing of the physics of flight, nor does the arrow paradox save the life of a person or animal struck by the arrow which cannot have flown.

We still have no idea just what time is, do we? We can measure it, expect it, hate it, love it, but we don't know what it is. Time isn't even a constant. Time slows as you approach the speed of light. Except that is a paradox of its own, I think. If a second stretches (time slowing) then wouldn't the "speed of light" change as you approach it?

This stuff gives me headaches and I eventually stop musing on it... In time.

1 See "http://en.wikipedia.org/wiki/Bumblebee#Flight"

2 comments:

FigMince said...

One the subject of arrows: An arrow fired at a cowboy's head will, at a certain time, be halfway to the head. Fast-forward, and at a certain instance it will be halfway to the head from where we last measured it. Fast-forward again etc, etc, etc, ad nauseum. So is it arguable that the arrow will never pierce the cowboy's head because it will always be halfway there from where it last was?

Damn. Now I've got a headache too. Must've been the arrow.

FigMince said...

One the subject of arrows: An arrow fired at a cowboy's head will, at a certain time, be halfway to the head. Fast-forward, and at a certain instance it will be halfway to the head from where we last measured it. Fast-forward again etc, etc, etc, ad nauseum. So is it arguable that the arrow will never pierce the cowboy's head because it will always be halfway there from where it last was?

Damn. Now I've got a headache too. Must've been the arrow.