however, radiation does turn back into matter all the time. For instance, a photon can (and does, all the time) turn into a positron-electron pair. Most of the time,these just collide back together again, giving us radiation again.
However, new theories suggest that there might be a slight break in this symmetry, in that you can break things like charge conservation, or other things like baryon number conservation. This would explaing why there is a lot more matter out there than anti-matter. If we lived in a universe which was not dominated by either matter or anti-matter then they would keep colliding, spewing forth radiation in from massive explosions, and you wouldn't get to read this somewhat rambling physics comment on a lazy Satruday afternoon from some wacko math guy.:)
Black hole emit radiation. Or so Stephen Hawking thinks, but I'm pretty sure he's right. So, the amount of energy available for life may fluctuate, but it will never be zero.
The _real_ problem is that you will eventually have a completely uniform universe, (maximum entropy) which means that there isn't a way to harness that energy.
On another note, it is interesting to note that we may already be in a black hole. If you look at the average mass density and size of the observable universe (which is about 10 or 15 billion light years in radius) and plug them into an appropriate formula (say here) then the universe has the gross properties of a black hole (the right size and mass). (It's important to note that size or mass completely describes a non-charged, non-spinning black hole).
So, falling into a black hole might suck (pardon the pun:] ) but living in one might be ok.
Stephen Hawking predicts that black holes _emit_ radiation (and therefore mass, ie matter).
Thus, in an open universe, the matter falling into black holes will eventually pop right back out. So, you don't really have to worry about this too much.
Isn't this kind of cirular logic? I mean, you're saying that measurements collapse a subject's wave function, and the definition of a measurement is something which collapses a subject's wave function.
No, according to the Schrodinger wave equation, which is the basis for most, if not all, of quantum mechanics, the particle does not have an exact position and momentum simultaneously.
The thing is, the two theories (general relativity and quantum mechanics) are both observable, and we _have_ verified each of them to a really quite impressive degree of accuracy, the extent of which I totally forget. These are real things which, metaphorically, you can reach out and _touch_.
However, they also provide contradictory results. for instance, relativity is deterministic (1 set of conditions produces 1 outcome) whereas quantum mechanics only predicts the probablility of events.
This is why we have all of these new (and, sometimes, really darn cool) theories telling us that we're really made out of 31.5 dimensional knots in a sea of quantum noise floating in man's hat full of perfume alongside a single plum.:D
Hate to burst your bubble, but black holes do emit light. It's called Hawking radiation, and, yes, it was discovered by Stephen Hawking, and, yes, he is financially sound.
You should write him about the banner idea, tho.;)
We actually haven't predicted the rest of the solar system's orbit for much longer than 10 millenia or so. It takes quite a lot of power to get a reasonably accurate prediction for timescales like these.
If any astro-computer geeks out there feel like showing off, I happen to know that there's research money out there for this.
Suppose we get rid of all of the common viruses out there.
Our bodies see that our immune systems are just sitting there, getting precious resources which could be otherwise spent growing, doing work, or storing energy for that famine our bodies seem to think is always just around the corner. Thus, our immune systems get less resources.
Problem is, once our immune systems don't have things like the common cold around to keep them honest, they start to suck. And then a real disease comes along and we're sol.
I can see it now. The organisms that we create evolve, become inteligent, and do all those neat things that biological things end up doing all on their own. They eventually come to the point where they can create life.
So, if we did it, why shouldn't they?
And if He did it, why shouldn't we?
(I'm not trying to troll here; this seems like it might be a valid point - I'm not sure. That's why I posted it onto a discussion forum);)
Let's see what possible reasons the mayor could have for calling it a state of emergency. Especially noting that anybody with a WTO id can avoid the curfew, no problem.
Wait, are they trying to stop the protest, even the legal parts of it, so lots of foreign business attracted to the city by the convention will stay?
It looks like (imho, anyways) that this is an arbitrary suspension of civil liberties designed to help people the mayor likes.
And I'm not usually prone to conspiracies of this sort, but, damn. This just isn't right.
The adaptions that seem to be working best right now is making decent products really cheaply by using workers in countries where you _don't have to respect civil rights_, using natural resources that are in very limited supply, in an environmentally harmful manner.
Hey, bring on the 386's. We can stand a couple less flops in order to prevent this from happening.
I think we need to get over itand stop arguing about things which happened 30 years ago. This discussion is about the wto and what good, if any, it's doing to our environment and working conditions all over the world. The fact that ONE of the protest groups calls themselves (or is called by Yahoo news) electrohippies isn't really the point. There are probably hundreds of organizations down in Seattle today to protest the wto.
The point of the wobble measurement is that they can't see the planet. They look at how it makes the star wobble about as it orbits it.
However, they can see the star, and find out how far away it is, and how much light reaches us, and thus find out how bright it is. The wobble can also tell us how far the planet is from the star by the period of orbit, and calculating the mass of the star from it's brightness. Then they know how much light hits it, which tells them how bright it is.
In fact, oxygen is so toxic that when some crazy microorganism started to produce it as a gas some 2 billion years ago, it caused a mass extinction bigger than the comet that took out the dinosaurs.
Or so it is believed. Microorganisms don't take too well to fossilization, especially for that long.
Compared to silicone, carbon is an extremely plentiful element in the universe at large. This is due to the fact that carbon is produced in the normal helium to hydrogen fusion reactions in normal, non-giant stars. Silicone, on the other hand, can only be produced (in any reasonable amount) in a supernova. Carbon is also produced in this manner.
So when a star explodes, it already has a bit of carbon in it, but hardly any silicone, so we end up with a lot more carbon to make squirmy things out of (eg: life).
So the problem is, as I see it, is that there just isn't enough silicone to go around.
Slashdot Mirror
However, new theories suggest that there might be a slight break in this symmetry, in that you can break things like charge conservation, or other things like baryon number conservation. This would explaing why there is a lot more matter out there than anti-matter. If we lived in a universe which was not dominated by either matter or anti-matter then they would keep colliding, spewing forth radiation in from massive explosions, and you wouldn't get to read this somewhat rambling physics comment on a lazy Satruday afternoon from some wacko math guy. :)
The _real_ problem is that you will eventually have a completely uniform universe, (maximum entropy) which means that there isn't a way to harness that energy.
On another note, it is interesting to note that we may already be in a black hole. If you look at the average mass density and size of the observable universe (which is about 10 or 15 billion light years in radius) and plug them into an appropriate formula (say here) then the universe has the gross properties of a black hole (the right size and mass). (It's important to note that size or mass completely describes a non-charged, non-spinning black hole).
So, falling into a black hole might suck (pardon the pun :] ) but living in one might be ok.
Thus, in an open universe, the matter falling into black holes will eventually pop right back out. So, you don't really have to worry about this too much.
Anyone remember that alleged nsa key that Microsoft put into windows? I wonder how the army would feel about that.
Isn't this kind of cirular logic? I mean, you're saying that measurements collapse a subject's wave function, and the definition of a measurement is something which collapses a subject's wave function.
Things are fundamentally fuzzy.
However, they also provide contradictory results. for instance, relativity is deterministic (1 set of conditions produces 1 outcome) whereas quantum mechanics only predicts the probablility of events.
This is why we have all of these new (and, sometimes, really darn cool) theories telling us that we're really made out of 31.5 dimensional knots in a sea of quantum noise floating in man's hat full of perfume alongside a single plum. :D
You should write him about the banner idea, tho. ;)
If any astro-computer geeks out there feel like showing off, I happen to know that there's research money out there for this.
Our bodies see that our immune systems are just sitting there, getting precious resources which could be otherwise spent growing, doing work, or storing energy for that famine our bodies seem to think is always just around the corner. Thus, our immune systems get less resources.
Problem is, once our immune systems don't have things like the common cold around to keep them honest, they start to suck. And then a real disease comes along and we're sol.
So, if we did it, why shouldn't they?
And if He did it, why shouldn't we?
(I'm not trying to troll here; this seems like it might be a valid point - I'm not sure. That's why I posted it onto a discussion forum) ;)
These things are important, and we should know about them.
Wait, are they trying to stop the protest, even the legal parts of it, so lots of foreign business attracted to the city by the convention will stay?
It looks like (imho, anyways) that this is an arbitrary suspension of civil liberties designed to help people the mayor likes.
And I'm not usually prone to conspiracies of this sort, but, damn. This just isn't right.
Hey, bring on the 386's. We can stand a couple less flops in order to prevent this from happening.
I think we need to get over itand stop arguing about things which happened 30 years ago. This discussion is about the wto and what good, if any, it's doing to our environment and working conditions all over the world. The fact that ONE of the protest groups calls themselves (or is called by Yahoo news) electrohippies isn't really the point. There are probably hundreds of organizations down in Seattle today to protest the wto.
However, they can see the star, and find out how far away it is, and how much light reaches us, and thus find out how bright it is. The wobble can also tell us how far the planet is from the star by the period of orbit, and calculating the mass of the star from it's brightness. Then they know how much light hits it, which tells them how bright it is.
Or so it is believed. Microorganisms don't take too well to fossilization, especially for that long.
So when a star explodes, it already has a bit of carbon in it, but hardly any silicone, so we end up with a lot more carbon to make squirmy things out of (eg: life).
So the problem is, as I see it, is that there just isn't enough silicone to go around.