Posted by
michael
on from the close-only-counts-in-horseshoes dept.
DrBlake writes "New York Times has an article about a study of Einsteins theory of relativity that I found very interesting. Not only might the speed of light be relative under certain circumstances, the famous equation E=mc2 might not be entirely correct."
That's the paradox...
by
starsong
·
· Score: 5, Informative
...and the beauty of special relativity.
They key thing is that the speed of light is fixed relative to *everything*. This means that if I'm standing by the highway and measure it, I get the same speed as a person in a car going 60 mph away from me. And since the speed of light is fixed, everything ELSE distorts to make up for it. That includes time (time dilation) and space (Lorentz contraction). It leads to some pretty freaky and amazing consequences.
Re:That's the paradox...
by
Trogre
·
· Score: 5, Informative
A good way to observe (well, simulate) some of these effects is to download lightspeed and have a play. Effects such as Lorentz contraction, doppler shift, headlight effects and optical aberrations can be observed. Very cool with the add-on Starship Voyager model.
There's also some very nice mpegs floating around the net of tram cars and flashing lamp posts in a world where the speed of light is slowed to a couple of meters per second. Now if only I could dig up the URL...
-- "Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
well, of course...
by
QID
·
· Score: 5, Informative
E=mc^2 is actually a simplified form of the real equation, E=mc^2/sqrt(1-v^2/c^2). A convenient graphical depiction can be found in a few seconds with google, or here: http://www.btinternet.com/~j.doyle/SR/Emc2/Derive. htm.
Re:gravity effects are instantaneous
by
rsidd
·
· Score: 5, Informative
Wrong. Newtonian gravity suggests effects should be instantaneous, that's why Einstein knew it was wrong and came up with the general theory of relativity, which is the best theory of gravity we have today (and unlike special relativity which was built on the work of others, GR was Einstein's own, nobody else was even thinking along those lines.)
As for magnetism, that travels at the speed of light -- that has been known since Maxwell's time. Basically, that's what electromagnetic radiation is: a changing magnetic field causes a changing electric field, which causes a changing magnetic field,.... The paradox was that Maxwell's equations give you a constant for the speed of light, without reference to the velocity of the observer, so people assumed that they are valid only in the rest frame of a mythical "ether". Einstein showed that Maxwell's equations are correct for all observers, and it is Newton's/Galileo's ideas which are wrong.
Incidentally, just like electromagnetic radiation, GR implies that gravity waves should exist too.
Einstein knew he was wrong
by
automatic_jack
·
· Score: 5, Informative
Not more than a few year's after developing his theories of general and special relativity, Einstein realized that they weren't perfect. The simple reason behind his realization was that the theories of relativity didn't make sense when applied on a quantum scale, and the theories of quantum physics didn't make sense when applies of a relative scale. Einstein refused to believe that the universe worked in such a way that there had to be two mutually exclusive theories to explain physics on the very small and the very large scale.
Of course, the rest of the world was busy experimenting with his theories of relativity, but after he published them he quickly lost interest in their progress. He spent the rest of his life searching for what he referred to as the "unified field theory," a single theory that could properly explain quantum physics and relativity at the same time.
I'm not a physicist by any stretch of the imagination, but theoretical science does interest me. Brian Greene's book, The Elegant Universe does a great job of explaining the background on this. It's worth a look.
--
--
Have you ever noticed that at trade shows, Microsoft is always the company that is handing out stress balls?
Re:You misunderstand completely
by
lars_stefan_axelsson
·
· Score: 5, Informative
I don't mean to be a troll, but I really want to ask this. Why is it so frowned upon to question evolution?
By the nature of science, it is granted that theories and current "knowledge" may be overturned in light of future counter-evidence. However, evolutionists give the impression that they consider their views to be rock-solid, indisputable Truth that is impossible to disprove now and forevermore. Anyone who dares to disagree is dismissed out of hand as a kook. (See, I had to post as AC to even ask.)
Well, I don't know if it's really the case that evolutionists consider their views to be a "truth that is impossible to disprove" etc. (at least not the scientfically minded ones, for any theory there are supporters that one could do without).
Now let me start by saying that I'm not really an expert on evolution, since I'm european I've never had to be. There are no creationists here to speak of, and hence I'm not well versed in their way of thinking. I am a "scientist" however, so I'm somewhat qualified to speak about that.
Now, not to write an essay answering your question, but much of it boils down to what we mean by "wrong." First some preliminaries though. The strength of any scientific theory rests on its predictive powers, how well does it foresay and explain the outcome of experiments or observations (past of future). Any good scientific theory then is very specific (or strong), what we like to call "easily falsifiable", i.e. it is simple to detect when its predictive powers are failing. (Hence many of them in the natural sciences are formulated in some form of logic; "mathematics" since that provides for a stronger statement to be made). So, strong theory equals "easy to prove wrong" given contradictory evidence.
Now, then what does it mean to be "wrong" in the scientific sense? In short it's when there are observations made that cannot fit into the current theory. A prime example would be Newton's law of kinetic energy E=1/2mv^2. For a long time that was thought to be all there is to it, and all the experiments and observations that could be made corroborated that. Today we know that it's not "true". It's OK for lower speeds, but it completely fails to take relativistic effects into account (see previous posts in this thread), and hence has been relegated to the scrap heap of scientific theories, right?
Well, not quite. It's still a very good approximation for most macroscopic real world phenomena. It still explains them very well, and even post Einstein, it hasn't really lost any of it's predictive powers in the domain in which it was thought up. So even though it may now be thought "wrong" in the strictest sense of the word; it may not tell all of the truth to all people, it's still a pretty darn good theory if you're a bit more careful with it's application.
This is also true of Darwinian evolution. It's a very well tested theory (or "fact" if you will) by now, with wast predictive and explanatory powers. Any later theory that superseeds it must still explain all the observations with the same (or better) accuracy as Darwinistic evolution has to date. So even though evolution as a theory may be proven "wrong" at a later date, it'll still be mostly "right." As Newtons' laws still are.
Now, in order to completely close the sack, we also need Occam's razor. I.e. given two equally predictive theories, we prefer the simpler one. It's really a common sense argument. Why make things harder than they have to be. It's also the only scientific loophole that creationists can exploit. By invoking a "deus ex machina" in the form of an omnipotent God, that stacks the deck so that scientists cannot make correct observations (or make them correctly), you can of course invalidate any and every theory. And that's why science doesn't deal with that. If someone stacks the deck, we won't play! (Then we can continue various philosophical arguments, and in doing so rapidly leaving the natural sciences.)
And that's incidentally why science isn't "just another religion", science specifically is about absolutely minimising the things that have to be taken on faith (such as the existence of the rest of the world etc), while religion(s) are about systematising the things you take on faith. Often that means that science cannot say very much on a subject, and people having a natural tendency towards taking things on faith, often over interprets scientific statements (it takes practice to so thoroughly disiplining your subjectiveness as the scientist must do). This leads to "scientific" statements or belif in the general public, that really aren't. But that's not the fault of science, more a fault of the schooling system.
If you're specifically interested in evolution, I have it on good authority that you could do worse than studying talk origins. I haven't got any good references on the philosophy of science in english for you, but I'm sure that a few minutes of googling will turn up a multitude.
Slashdot Mirror
NYT article
...and the beauty of special relativity.
They key thing is that the speed of light is fixed relative to *everything*. This means that if I'm standing by the highway and measure it, I get the same speed as a person in a car going 60 mph away from me. And since the speed of light is fixed, everything ELSE distorts to make up for it. That includes time (time dilation) and space (Lorentz contraction). It leads to some pretty freaky and amazing consequences.
E=mc^2 is actually a simplified form of the real equation, E=mc^2/sqrt(1-v^2/c^2). A convenient graphical depiction can be found in a few seconds with google, or here: http://www.btinternet.com/~j.doyle/SR/Emc2/Derive. htm.
As for magnetism, that travels at the speed of light -- that has been known since Maxwell's time. Basically, that's what electromagnetic radiation is: a changing magnetic field causes a changing electric field, which causes a changing magnetic field, .... The paradox was that Maxwell's equations give you a constant for the speed of light, without reference to the velocity of the observer, so people assumed that they are valid only in the rest frame of a mythical "ether". Einstein showed that Maxwell's equations are correct for all observers, and it is Newton's/Galileo's ideas which are wrong.
Incidentally, just like electromagnetic radiation, GR implies that gravity waves should exist too.
Not more than a few year's after developing his theories of general and special relativity, Einstein realized that they weren't perfect. The simple reason behind his realization was that the theories of relativity didn't make sense when applied on a quantum scale, and the theories of quantum physics didn't make sense when applies of a relative scale. Einstein refused to believe that the universe worked in such a way that there had to be two mutually exclusive theories to explain physics on the very small and the very large scale.
Of course, the rest of the world was busy experimenting with his theories of relativity, but after he published them he quickly lost interest in their progress. He spent the rest of his life searching for what he referred to as the "unified field theory," a single theory that could properly explain quantum physics and relativity at the same time.
I'm not a physicist by any stretch of the imagination, but theoretical science does interest me. Brian Greene's book, The Elegant Universe does a great job of explaining the background on this. It's worth a look.
-- Have you ever noticed that at trade shows, Microsoft is always the company that is handing out stress balls?
Well, I don't know if it's really the case that evolutionists consider their views to be a "truth that is impossible to disprove" etc. (at least not the scientfically minded ones, for any theory there are supporters that one could do without).
Now let me start by saying that I'm not really an expert on evolution, since I'm european I've never had to be. There are no creationists here to speak of, and hence I'm not well versed in their way of thinking. I am a "scientist" however, so I'm somewhat qualified to speak about that.
Now, not to write an essay answering your question, but much of it boils down to what we mean by "wrong." First some preliminaries though. The strength of any scientific theory rests on its predictive powers, how well does it foresay and explain the outcome of experiments or observations (past of future). Any good scientific theory then is very specific (or strong), what we like to call "easily falsifiable", i.e. it is simple to detect when its predictive powers are failing. (Hence many of them in the natural sciences are formulated in some form of logic; "mathematics" since that provides for a stronger statement to be made). So, strong theory equals "easy to prove wrong" given contradictory evidence.
Now, then what does it mean to be "wrong" in the scientific sense? In short it's when there are observations made that cannot fit into the current theory. A prime example would be Newton's law of kinetic energy E=1/2mv^2. For a long time that was thought to be all there is to it, and all the experiments and observations that could be made corroborated that. Today we know that it's not "true". It's OK for lower speeds, but it completely fails to take relativistic effects into account (see previous posts in this thread), and hence has been relegated to the scrap heap of scientific theories, right?
Well, not quite. It's still a very good approximation for most macroscopic real world phenomena. It still explains them very well, and even post Einstein, it hasn't really lost any of it's predictive powers in the domain in which it was thought up. So even though it may now be thought "wrong" in the strictest sense of the word; it may not tell all of the truth to all people, it's still a pretty darn good theory if you're a bit more careful with it's application.
This is also true of Darwinian evolution. It's a very well tested theory (or "fact" if you will) by now, with wast predictive and explanatory powers. Any later theory that superseeds it must still explain all the observations with the same (or better) accuracy as Darwinistic evolution has to date. So even though evolution as a theory may be proven "wrong" at a later date, it'll still be mostly "right." As Newtons' laws still are.
Now, in order to completely close the sack, we also need Occam's razor. I.e. given two equally predictive theories, we prefer the simpler one. It's really a common sense argument. Why make things harder than they have to be. It's also the only scientific loophole that creationists can exploit. By invoking a "deus ex machina" in the form of an omnipotent God, that stacks the deck so that scientists cannot make correct observations (or make them correctly), you can of course invalidate any and every theory. And that's why science doesn't deal with that. If someone stacks the deck, we won't play! (Then we can continue various philosophical arguments, and in doing so rapidly leaving the natural sciences.)
And that's incidentally why science isn't "just another religion", science specifically is about absolutely minimising the things that have to be taken on faith (such as the existence of the rest of the world etc), while religion(s) are about systematising the things you take on faith. Often that means that science cannot say very much on a subject, and people having a natural tendency towards taking things on faith, often over interprets scientific statements (it takes practice to so thoroughly disiplining your subjectiveness as the scientist must do). This leads to "scientific" statements or belif in the general public, that really aren't. But that's not the fault of science, more a fault of the schooling system.
If you're specifically interested in evolution, I have it on good authority that you could do worse than studying talk origins. I haven't got any good references on the philosophy of science in english for you, but I'm sure that a few minutes of googling will turn up a multitude.
Stefan Axelsson