This post was written three days in the future from now. I have been informed that it is still not possible to send information to the past without messing it up. I hope this warning message makes it to you: do not travel to the past, I repeat, do not travel to the past. It’s messed up man….
As you can see, the laws of physics are still holding. The last of the three elementary concepts is time. Time seems to be different than space, and also than mass. Time is always there, never stopping, not once, not ever. Well, except in some seminars I attend to where time does seem to stop. I must check into that and see if I can profit.
So how do we notice that time is there? There seem to be these things that happen again and again and again and again. We call them days. Then we notice that there are these things called years: you notice because of the seasons, and if you happened to be a hunter-gatherer, the winters seem to have very little gathering available. Well, maybe a lot of wood-gathering to keep warm. But I digress. In some sense time is this little beast that lets us repeat stuff. However, there seems to be no rewind button, and let me tell you, there are times where I wish I had one…
So we get to the problem of once you have time, how do you measure it? You build a clock, silly! There is a ‘natural clock’ out there. I described it to you: there are days and nights and years. There is also a moon which circles the earth somewhere in between 27 and 28 days. However, the lunar month seems longer because we are also revolving around the sun and the phases of the moon evolve slower. Then you can check your facts on the internet. That is, assuming that the information one is reading is correct….
Now, back to time. It seems to be always pointing towards the future. You know what I mean. Eddington gave it a fancy name. He called it the arrow of time. Some people want to talk about it a lot. I just know it’s there. It is the arrow that kills you in the end: we are sure that everyone dies.
Also, time is the thing that lets us repeat experiments. We can collect data many times and compare them. It seems to be an essential part of the scientific method. And everyone who is a professional at this thing called physics knows that you should take your time to do things right, rather than be sloppy and in a hurry. Sometimes you do have to hurry, there are deadlines and such, and in the labs you have emergencies. And then you don’t sleep for a couple of days and can get really crabby. Not good for the peace of mind, no sirree.
Now, you have all heard that time is money. That can lead to some cookie equations, but it is a reality in the economic sense. Tv stations sell time for adverts. These are parceled into equal time segments. Cellphone carriers also sell time. You realize how much of a good business it is when you check your monthly phone bill. Time is also used to punish people: you clobber them with a clock.
Here is a nice quote by Bertrand Russel:
The time you enjoy wasting is not wasted time
I think it describes all you internet surfers. I spotted it first on the door of one of my colleagues here. Hope that makes you feel better.
If you want to find some other quotations about time, check these. If you go to the bottom of the page and do a little bit of hyperlink-chasing you can also find some cool quotes about the past, the future and pretty much anything else. That’s your homework exercise.
I bid you adieu, as I am out of time.