In a highly ambitious attempt to test out of my physical science class, I'm attempting to assimilate my textbook in time for the challenge test on Monday. This wouldn't be ambitous, but I didn't start reading ahead until today.
Now. We've all seen little videos or junior high textbooks try to give lay explanations of Einstein's work, trying to not fry the poor layperson's brain in the process. This is the first time I've gotten my hands on an academic explanation, more out of laziness than anything else.
Anyway. If I understand this correctly--IF I understand this correctly--light passes an object--regardless of the object's velocity--at the same speed, the speed of light. If you have a person on a train that is travelling near the speed of light, and lightning strikes the tracks behind the train, the person will see the event at "regular speed", that is, he won't see it in slow motion or anything like that as light from different phases of the strike catch up to him. The lightning will seem to occur at a normal rate from his perspective. He will, of course, see the lightning strike the tracks much later than someone who was standing by the tracks as they were struck (assuming the person who was standing by the tracks wasn't fried before he registered anything).
Now this is where my sanity explodes in a giant ball of flaming blue stuff and penguins bury it in a black hole. What about what the person on the train is seeing BEFORE he sees the lightning strikes the tracks? Let's say there is one second between the time the train passes over the spot where lightning will strike and the time at which the lightning actually strikes, and the train is travelling so fast that it takes the light from the strike a full ten seconds to catch up to the person on the train. What is he watching during those ten seconds? The sun was only bouncing photons off that spot on the tracks for one second before the lightning; one second's worth of photons. He watches this one second's supply of photons for a full ten seconds before he registers the lightning. The tracks can only reflect so many photons off in that one second; for the sake of having a random number to work with, let's say it bounces a thousand off in that second, and a thousand photons provide the view of the tracks at full luminosity. I know a thousand is way off, but that's not the point here. There is a record of the time between when the train passed and when the lightning struck, and that record is the thousand photons. Since the person on the train is being hit with light at the same speed as he would were he standing still, he's not watching that one second in slow motion. It doesn't look really dark, so he's getting the full thousand photons required per second to show the scene at full lighting. But he's collecting a thousand photons per second for TEN SECONDS, for a total of TEN THOUSAND PHOTONS of the pre-strike tracks before he registers the lightning strike. The tracks only reflected ONE thousand photons after the train passed but before the lightning struck. WHERE THE FREAK ARE THE EXTRA PHOTONS COMING FROM?
Emmett, please, please, please, PLEASE tell me that I've made some MAJOR error here, or that there's a perfectly reasonable explanation, like photons being imported from another universe, because this question is DESTROYING my SANITY! AGH!
Anyway, it's back to reading my whole textbook. Thank you and good night.
--Paul
P.S. THE PENGUINS ARE COMING, THE PENGUINS ARE COMING!
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5 comments:
Sorry about those extra photons...I blame the Q. The Q are a good thing to blame. They like playing with us dumb humans.
And I thought my 2 anthropology chapters were giving me a headache. Forget me!
And the penguins are compliments of The Muppet Show. When they get too irritating, just through them in the air. They're used to it.
Good luck, Paul! :)
I got my own blog. Peer pressure, eh? So it's at nocommentzone.blogspot.com
Come check it out!
I'll be updating it after church. Oh, and I'll talk about Paul's post
Okay, I'll try to fit this all into a comment box. There are no nine thousand photons. The problem comes with your description of the passage of time. The ten seconds, if measured by an otside observer, is much more time than the people on the train experience. And you're talking about ten seconds train experience, then they couldn't describe the moment in terms of exactly when the lightening hit, only in terms of when they saw it. There would also be a continuous stream of light from that spot, so they would be continuously overtaken by those photons until they saw the lightning. Hope that helps.
I agree with Emmett (it would be dangerous not to), but I don't know that the character of light has been settled. In my physics class, the presenter explained that even the laws that we assume to be true do not exactly fit the whole universe. F, for example, does not necessarily equal ma. Newton was not wrong. For earth, anyway. But that's too deep to go into right here. If you think of photons as a continuous stream, then the lightening bolt would be seen on the train as it would be seen by an outside observer--just later than the outside observer. If there are spaces between photons, however, then you would see it like film slowed down. Time is a factor, if you believe Einstein. Anyway, the professor said it's always dangerous to rely on theorists for practical or real-world answers. For example, the problem you describe would not come up even if the train ride was possible because everything would seem like a blur to you. Unless time slows for you. That is, if you believe a theorist, even if he is the most brilliant one out there.
P.S. Dark matter is not real--it's just something physicists made up to make theorists right.
...I guess I did forget the relativistic property of time.
*breathes sigh of relief*
Sanity restored. As much as I ever have, anyway.
And antihydrogen isn't dark matter; it's anti matter!
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