Of course you know what time is, since you’ve read From Eternity to Here and you don’t buy into the mysterianist gobbledygook that often accrues to the subject. But not everyone is so fortunate. (Or my sales would have been a lot better.) So Alan Alda has laid down the gauntlet: explain time to an 11-year-old.
This is the second iteration of the Flame Challenge, so named because the first question asked was “What is a flame?” The level of abstraction is a bit higher here, and the challenge correspondingly greater.
The deadline is March 1, so plenty of time to come up with a compelling story for those of you who are tempted to rise to the challenge. There are two categories, “Written” and “Visual,” so don’t think that you necessarily have to produce a little movie to be the winner. I might enter myself, although frankly I don’t think it’s possible to do a good job in less than four hundred pages.
This seems really tough, considering even physicists do not seem to have a consensus on the issue of time. I’ve watched some videos about that very subject by a certain blogger/cosmologist – you may have heard of him.
I guess you first need to explain entropy and then simplify the rest of the debate… or something.
Easy:
Unlike space, time is just what you think it is.
For an eleven-year-old:
How will you tell your friend where is your home? By showing your home on a map. What if she was from another city? You have to use a larger map. What if she was from Marsh? Then you need to use the map of Solar System and tell her you live on earth. So, we can tell each other where we live by showing our address on a map.
Time is an address too! If one takes many many maps or pictures of the universe and puts these frames next to each other, they will make a move which is just like our usual universe. Therefore, time is just another address. Instead of giving you an address on a map, it tells you which map to look for. That map address is what we call time.
The reason we don’t tell each other both our time address and map address is because our city maps do not change that often, maybe after years. If your city map change every day, then be sure you had to tell your friend to look for you on a map that was made two days ago, as well as telling her the exact spot you lived on it.
For a physicist:
Entropy + Einstein / spacetime ^ time dilation …. Okay! I don’t know the answer! Are you happy now? But I want to pick that as my Ph.D. thesis :p
Time is clearly gravity. No mystery there.
Time is a marker of change.
Time is nature’s way of preventing everything from happening at once.
I look at these things the way a non scientist with little education might (my credentials). Time is an infinitely scaleable measuring stick that man devised to measure the rate of change as it occurs around us.
this just occurred to me :
one big thing that is compelling about Alan Alda as a science host : his voice is reminiscent of Feynman.
Time is measure, uncertain or only probable at best.
Life without measure is absolute,
True.
=
I wish I could explain time to myself, and I’ve been thinking about it for many years. Its more than just a kind of ‘map’ (the problem with the time-line idea is, how fast is ‘now’ moving?). I think the central idea is, time is what things that happen, happen in. If there was no time, there wouldn’t be any way for anything to happen.