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E ~ mc^2
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UNIX was not designed to stop you from doing stupid things, because that would also stop you from doing clever things. -- Doug Gwyn
The more we learn (Score:2, Insightful)
Even if he was off.. (Score:4, Insightful)
Light Speed Relative? (Score:2, Insightful)
Comment removed (Score:3, Insightful)
E != mc^2 (Score:5, Insightful)
Re:can someone explain to me (Score:2, Insightful)
Re:It's been "disproven" for quite a while now... (Score:2, Insightful)
Even if his theories are improved (Score:4, Insightful)
I dont see the big deal in "disproving" him. It's sad that people will take some sort of glee in thinking "Ha! Einstein was wrong!" Einstein himself would be glad to see people come closer in figuring out the natuer of the universe.
Given the knowledge and tools available to him at the time, its amazing he came up with something in 1904 that people nearly 100 years later are still trying to figure out how to improve or disprove. Today we have the advantage of knowing how to look at things the way he did.
Einstein's abilities, creativity, and ideas will have a permanent influence on humanity's acheivements.
You misunderstand completely (Score:4, Insightful)
The very thing that shakes your faith in our knowledge is the very thing that *strengthens* our knowledge.
Think about it.
KFG
Re:can someone explain to me (Score:5, Insightful)
The speed of light is constant in all possible frames of reference, according to Einstein. Basically what he's saying is that for any two objects at rest relative to each other (regardless of their motion to the rest of the universe, they appear not to be moving to *each other*), time and space behave in the same way. The beauty of his theory is that no one object can be said to be at universal rest to everything else -- there is no universal frame to measure against. Therefore, every frame of reference is valid and will behave the same way. This kills Ether theory dead, since Ether theory depends on a universal frame of reference. If it didn't have a universal frame of reference, then space and time would start behaving oddly within your *own* frame of reference depending on your motion. This is not the case - the light on Pluto behaves the same way as the light on Earth, even though the two are moving in different frames.
It's only when you introduce out-of-frame references (I'm standing still, the train is moving at 60mph away from me) that relativity kicks in and the laws start to behave weirdly.
Not inconsistantly, just weirdly. It's all in shifting your viewpoint.
The trick with light is to realize that although it travels at the same speed in every frame of reference, the *wavelength* is what changes between frame. This is what that whole red-shifting/Doppler effect is about. The speed of light is constant; the color, however, changes depnding on your frame of reference. If you shoot a blue light at me while we're both standing still relative to each other, it looks blue to me. If I run away *really fast*, it will still be blue to you, but it will appear red to me because the wavelength alters even though it still travels toward me at a constant rate. Ditto if *you* run away from me - the light is blue to you, but again, it appears red to me, even though it travels at the same speed.
Light does not behave in the Newtonian way - acceleration does not effect its speed, only its wavelength. That's where the question of why light is constant to everything, even moving objects, is answered.
Weird, huh?
For a far, far, better explanation (and a fantastic grounding on String Theory in terms for non-physicists) check out The Elegant Universe [amazon.com] by Brian Greene. If I could, I'd give this book a Pulitzer every year until the day I died.
Re:Hitler knew that (Score:1, Insightful)
Re:No, what this is saying is that. . . (Score:3, Insightful)
Wow. You really have taken an advanced physics class! (not being sarcastic at all) In my brief experience with quantum mechanics, that's pretty much all it is. Sure, there's math to back up most of it, but a lot is just "classical parallels".
some physicists believe they may be seeing things at the macro level that are unexplainable by Relativitly theory
Something like when you examine a classical system of a partical moving in a one-dimensional region of definite length (the 1D infinite square well), you can see that it is equally probable to find the particle at any distance from the sides. However, quantum mechanically, the particle has a definite probability of being in the centre and said probability decreases like a gaussian distribution as it approaches either boundary. However, this is only for the ground state. As you get to higher and higher energy levels, you start to notice that the QM probability begins to resemble the classical one. But I'll leave with the best quote ever, which means my sig is finally applicable:
Re:It's been "disproven" for quite a while now... (Score:3, Insightful)
I've read many things and heard many things that supposedly came from Einstein's theories. Examples are that time travel is impossible, faster than light (or even fast as light) travel is impossible, and others. Many of these simply are not true.
Einstein himself said that in order to understand the theories, you need to be able to think in the abstract. There are few that can, even those who have been well trained in the areas of physics that take Eistein's theories into account.
As for the speed of light itself, I submit that it may not be the speed of light that is changed, but the nature of the universe around it that has. The reason that light bends in a gravitational field is not because light is slowed, or even that it bends, it's because space itself is different. Our space is curved and warped, moreso around massive objects, and like an object traveling along a bumpy, uneven path, light too will change apparent direction and speed. Change other properties of the physical space through which light travels, and that too will appear to affect the speed of light (and possibly its direction). But is the speed of light really changing, or is it just our relativistic perception of it?
PGA
Occam's Razor. . . (Score:5, Insightful)
First off, I'm not a creationist. Indeed, I find that whole debate to be entirely infernal, as both sides seem to me quite flawed in their own ways. That being said. .
Occam's Razor bugs me. As a deductive tool, it is a pretty good one; it works for the most part. What I find unsettling, however, is that it seems to have become, thanks to its presentation and treatment in popular media, understood and accepted by many as a de facto scientific law when it is not.
It is a rule of thumb, and only a rule of thumb. --It is only a rule of thumb, because it is not always right. Every time something unexpectedly complex turns out to be the reality behind a phenomenon which might otherwise have been explained through simple means, Occam's Razor is blunted.
Example:
When Alexandre Graham Bell first announced to the world that he had discovered a way to send a voice signal over a wire, the world erupted with both excitement and disbelief. One major newspaper even ran a story written by experts which attempted to debunk Bell's claim. They used diagrams demonstrating that sound waves sent down thin metal tubes of the diameter Bell was using for wires, could not possibly travel the kinds of distances he claimed. The experts were engineers well versed in the science and dynamics of sound as employed in the kinds of voice communication pipe systems once used large ocean going vessels. To the writers of the article, they were being entirely reasonable.
"Which is more likely?" they must have asked themselves, "That Bell has created some magical new invention to send sound along miles of very thin tubes? Or that he is lying?"
Occam's Razor is deeply rooted in how one perceives, how much information there is available to work with, and what has been previously accepted by culture as normal and/or outlandish.
-Now Bell was, of course, proven to be right. When words crackled out from crude speakers for all to hear, the enthusiastic debunkers, (and there is never any shortage of enthusiastic debunkers or respected, conservative media outlets to give them a voice and print their diagrams), had to quietly go mum and withdraw their objections. But that was in part due to large forces which wanted and allowed Bell to be proven right. If you don't advertise a fact or discovery, facts and discoveries can easily vanish. People have short memories. People have short lives. Without active perseverance, knowledge is a self-burying commodity until it becomes large enough to self-sustain, and even then, it is not so very difficult to forget important turns of history after only a few fickle generations have passed.
Science as a concept, is a pure, wonderful thing, but it does not know everything. Indeed, many institutions are not so pure as the science which they employ; it is well known that individuals with weak morals, and corrupt institution will suppress data, twist data and even make up data on a basis regular enough that the public pool of knowledge has been polluted to the point that the employment of Occam's Razor is by no means reliable in today's arena of public thought.
Just something to consider next time you feel the need to slam a new idea. Remember that Occam gave us a deductive tool, not an irrefutable law.
-Fantastic Lad
Re:You misunderstand completely (Score:5, Insightful)
In any case, argument from design doesn't provide any "explanation," much less a better one. How did the designer make the beetle, and all its close genetic relatives, where none had existed before? Why the variety of mechanisms in the close relatives, instead of a single design?
Re:You misunderstand completely (Score:5, Insightful)
Wrong. We also can't see electrons, or stars/galaxies at the edge of the universe. We don't need to see them to observe them though. Evolution has been observed in the fossil record, and even to some extent in the laboratory. Still, the lab observations are fairly new (the last 30-40 years) and science is busy debating whether or not it is indeed evolution... after all, as you pointed out, it is a slow effect.
Furthermore, no evolutionist has ever explained creatures like the Bombardier Beetle and its built-in flame thrower.
Huh? Of course evolutionists don't know everything at once... they don't claim to be omniscient. However, that doesn't mean they are doofuses without a clue. There have already been several possible explanations suggested in the scientific community, and no one disputes that something unknown is going on. You must not be researching this issue very thoroughly, if you believe there are no explanations at all, and that biologists are all sitting around dumbfounded.
Some of the more radical ideas center around the possibility that DNA acts more like a computer than a raw blueprint. That it might "store" a bunch of "mutations", saving them for a rainy day when some threshhold is reached. This "computer" might even span many individuals in the population. So instead of a gradual change into a "bombadier beetle" where there are many transitionary variants doomed to blowing themselves up, evolution simply "skipped over" those and went straight to the version capable of blowing up its enemies, and not itself.
Was it Greg Bear that said "Even evolution is evolving, becoming better at what it does." ?
Besides, lay off Darwinian evolution. Most people today see it as only the crudest approximation of the reality of evolution. Would figure that a bible thumper would be reacting to the scientific community of 100 years ago... you guys are always more than a few steps behind.
Re:You misunderstand completely (Score:2, Insightful)
You are absolutely right in asserting that the probability isn't so great--and not only for that; there are many, many other factors that might come into play when discussing a planet and whether or not it is fit for life, most of which are also with a low probability. But guess what? There's universe is so friggin' huge that even with those small odds it's not so surprising that it has happened, and it's also not completely out of line to think that it has happened more than once (i.e. life on other planets).
Re:PLEASE torture me with that! (Score:3, Insightful)
Ah. I'm not going to be able to do more than point you in the right direction in one
At that point, there's enough information to head over to the General Relativity chapter and take a gander. That ought to be enough to blow your mind for a little while as what you thought you knew about the universe resorts itself (don't worry, it happens to almost everyone).
After that, you can finish the book, develop some basic tensor math skills, then come back and explain Special Relativity to all of us! Actually, I do get Special Relativity, but it is mind bending. You really start thinking about the universe on a completely different scale.
I found it incredibly interesting stuff to learn, but because I went to a non-top-twenty school, there were only a few other people in my class with any interest. The hostility from the other undergrad students who hated learning (and especially hated having to rethink the universe) was a bit of a downer for the in-class exchange that the prof was so hoping for.
The graduate level classes were much more fun.
Regards,
Ross
Re:I hate to say this... (Score:3, Insightful)
You can write down music, but the written music is just a description, not the actual music. In the same way, math is a handy, concise, notation used to write down descriptions of the universe.
Re:Einstein knew he was wrong (Score:2, Insightful)
Re:Even if he was off.. (Score:2, Insightful)
Re:You misunderstand completely (Score:3, Insightful)