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Posted: 12/18/2003 9:46:49 AM EDT
can someone please explain Einstein's theory to me?
Link Posted: 12/18/2003 9:48:17 AM EDT
The angle of the dangle is proportional to the heat of the meat. Dave S
Link Posted: 12/18/2003 10:06:04 AM EDT
[Last Edit: 12/18/2003 10:13:55 AM EDT by HardShell]
[SouthernDrawl] Down heah, the only "theory of relativity" we concern ourselves with is how "distant" must a cousin be to date/marry her - theories vary... [/SouthernDrawl] [:D] Seriously, here is a post on a physics discussion board to a question just like yours. I hated/barely survived physics & calculus, so I have no idea how true any of the following is - but it's on the Internet, so it has to be true, right? [;)]:
#1 The Special Theory of Relativity contains many mistakes. That may be why you are having trouble understanding it. Very few physicists will admit that it contains any mistakes at all. #2 The General Theory of Relativity (GTR) contains many mistakes too. Einstein withdrew two of the main sections of the GTR in a paper he wrote in 1932. Modern Einstein supporters will never tell you this. #3 Both theories, which, together, are often just called “The Theory of Relativity”, have become a type of sophistry or hoax. They are used to try to give the world the impression that only scientists and teachers who claim to understand them, actually can understand them; whereas, in reality, most scientists and teachers don’t really understand them. They only claim to understand them because they feel that that is what scientists and teachers should do.
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Link Posted: 12/18/2003 10:14:49 AM EDT
[Last Edit: 12/18/2003 10:16:11 AM EDT by FLAL1A]
What's "relative humidity?" The sweat beads that form on your sister-in-law's upper lip while you're screwing her.
Link Posted: 12/18/2003 10:15:46 AM EDT
"Put your hand on a hot woman, an hour can seem like a minute. Put your hand on a hot pan, a minute can seem like an hour. It's all relative" Quote from a movie, I can't remember the title.
Link Posted: 12/18/2003 10:20:02 AM EDT
Here it is direct from the source: [url]http://www.bartleby.com/173/[/url] [>:/] Fill me in when you figure it out.
Link Posted: 12/18/2003 10:20:23 AM EDT
I have a good friend who was a nuc in the Navy. He developed a way of describing the Theory to folks who he refers to as 'deck apes'. All deck apes know about radiation is that it eats your nuts. Ok, here it is: Dave's Dumbed-Down Dense Deck-Ape Relativity Explanation: What is, is. What ain't, ain't. And if you wanna take something that ain't and make it is, you gotta take something that is and make it ain't.
Link Posted: 12/18/2003 11:00:51 AM EDT
Doesn't the theory of time and relativity say that time goes slower when you're with your relatives ???
Link Posted: 12/18/2003 11:06:27 AM EDT
Originally Posted By TexasEd: Doesn't the theory of time and relativity say that time goes slower when you're with your relatives ???
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*whew* I'm glad you posted this. It looked a couple of guys were going to spoil a beautiful hijacking.
Link Posted: 12/18/2003 11:12:17 AM EDT
I know that E=MC2 can be proved...we did this in our physics class, but the entire theory is still debatable. Most people assume that E=MC2 is the 'theory of reletivity', but as others have mentioned, it is only a small part of several theories.
Link Posted: 12/18/2003 11:43:47 AM EDT
[Last Edit: 12/18/2003 11:45:53 AM EDT by darealickt]
What a perfect time to ask this question. I just yesterday took my final exam in quantum physics and relativity. Here is the most important thing to remember in relativity: [b]The Laws of Physics are Frame-Independent[/b]. Essentially, this means that the laws of physics are the same inside a laboratory moving at a constant velocity as they are inside a laboratory at rest. When thinking in relativistic ways, one must always think in terms of "frames", the two types of which being inertial and non-inertial frames. A frame is defined to be a rigid cubical lattice of appropriately synchronized clocks, or its functional equivalent. The spacetime coordinates of an event in a given reference frame are defined to be an ordered set of four numbers, the first being the time of the event as registered by the nearest clock in the lattice, followed by three numbers that specify the spacial coordinates of that clock in the lattice (x,y,z). Here is The Principle of Relativity: [i]The laws of physics are the same in all inertial reference frames.[/i] That should get you started...
Link Posted: 12/18/2003 12:02:30 PM EDT
I may be an AR-15 newbie, but I think I can help you here. First, E=mc^2 is *not* relativity. It's mass-energy equivalence (and how Star Trek's antimatter engines work). Here's an oversimplified way of looking at relativity. You are driving a school bus toward me at, say, 30 mph. I'm standing on the ground a mile away (this is important later). You turn on your headlights. How fast does the light travel from your headlights to my eyes? From elementary school science, we know that light travels 186,000 miles per second. (We'll neglect the "in vacuum" part of the speed.) So this means that the light from the headlights is travelling 186,000 miles per second PLUS 30 miles per hour, right? We'll answer that in a minute. First, let's consider something a little easier to work with. Let's look back into the bus (which is moving along the ground at 30 miles an hour) where the kids are. Two kids have stolen the school nerd's shoes. A kid at the back of the bus throws them to his friend at the front of the bus. How fast did he throw the shoes? It depends - and not just on the kid's arms. From what "frame of reference" are you measuring the shoes' speed? Since you're on the bus, you'll probably use the bus as your frame of reference. We'll say that the shoes fly down the bus at 50 miles an hour, RELATIVE to the bus. But relative to me (remember me, standing a mile away on the ground), they're moving 50 mph (from the throw) PLUS 60 mph (because the bus is moving relative to me). Now grasp your hat and hold it tightly, because I'm gonna blow your mind. Relativity says that light (electromagnetic radiation of any kind, actually) does not do what we just described. The speed of light is constant in all frames of reference, according to theory. So the light from your headlights (remember them) DOES NOT move at 186,000 miles per second PLUS 30 mph. It moves at 186,000 miles per second no matter where you are or how fast you're moving. Let's pretend that the nerd's shoes behave the way light does in this theory. This means that the shoes move at 50 mph relative to the bus (and to you, the driver). It also means that they move at 50 mph relative to me (in another frame of reference, specifically on the ground). The only way that this can physically happen is if time moves at different speeds in different frames of reference. In our example, the only way for the shoes to move at 50 mph relative to me is if time moves faster for me than for you on the bus. I understand that there is some experimental evidence for this, but opinions may vary. That's the short (?) answer. Hope it helps.
Link Posted: 12/18/2003 12:55:29 PM EDT
I think the above experements involved syncronized atomic clocks on the Apollo space craft and other tests on high speed air craft. The clocks on these vehicles were indeed behind the 'control clock' on earth...in other words..time moved slower in the faster 'frame' as another mentioned.
Link Posted: 12/18/2003 1:00:09 PM EDT
Originally Posted By QuietShootr: Ok, here it is: Dave's Dumbed-Down Dense Deck-Ape Relativity Explanation: What is, is. What ain't, ain't. And if you wanna take something that ain't and make it is, you gotta take something that is and make it ain't.
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And that's why this theory has been superseded by Quantum Mechanics, because if you have something that ain't, just watch it for a bit and it changes into something that wasn't.
Link Posted: 12/18/2003 1:15:29 PM EDT
My brain hurts. Actually, trachnload that was an excellent explanation.
Link Posted: 12/18/2003 1:19:21 PM EDT
[Last Edit: 12/18/2003 1:22:02 PM EDT by SGTIMAK]
Originally Posted By trachnload: Now grasp your hat and hold it tightly, because I'm gonna blow your mind. Relativity says that light (electromagnetic radiation of any kind, actually) does not do what we just described. The speed of light is constant in all frames of reference, according to theory. So the light from your headlights (remember them) DOES NOT move at 186,000 miles per second PLUS 30 mph. It moves at 186,000 miles per second no matter where you are or how fast you're moving.
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So what happens when you're moving at or faster than the speed of light and turn on the headlights? edited: Is that when you see the "Star Wars jump to light speed" scene with the stars and everything getting stretched out and distorted?
Link Posted: 12/18/2003 1:25:48 PM EDT
Originally Posted By Kar98: And that's why this theory has been superseded by Quantum Mechanics, because if you have something that ain't, just watch it for a bit and it changes into something that wasn't.
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Quantum theory hasn't superceded Relativity. Think of it more like: If you want to explain how really small stuff works, then use Quantum theory. If you want to explain how normal size stuff works, use Relativity. They both work, just on their own level.
Link Posted: 12/18/2003 1:28:25 PM EDT
I recommend trying a search on this topic, as there have been plenty of threads. I would expound but just got home from my quantum mechanics final and don't feel like it.
Link Posted: 12/18/2003 1:31:13 PM EDT
Originally Posted By HardShell:
#1 The Special Theory of Relativity contains many mistakes. That may be why you are having trouble understanding it. Very few physicists will admit that it contains any mistakes at all. #2 The General Theory of Relativity (GTR) contains many mistakes too. Einstein withdrew two of the main sections of the GTR in a paper he wrote in 1932. Modern Einstein supporters will never tell you this. #3 Both theories, which, together, are often just called “The Theory of Relativity”, have become a type of sophistry or hoax. They are used to try to give the world the impression that only scientists and teachers who claim to understand them, actually can understand them; whereas, in reality, most scientists and teachers don’t really understand them. They only claim to understand them because they feel that that is what scientists and teachers should do.
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Argh.... the theories accurately explain observed phenomena, and there are no contradictions that I am aware of. Seems to me the guy who originally wrote the above is bitter because he couldn't hack it when it came to physics. special relativity--velocity dilates time general relativity--acceleration (i.e. gravity) dilates time
Link Posted: 12/18/2003 1:34:48 PM EDT
Originally Posted By Kar98: And that's why this theory has been superseded by Quantum Mechanics, because if you have something that ain't, just watch it for a bit and it changes into something that wasn't.
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QM has not superceded relativity. The theories explore different domains. Some people earn a living trying to unite the two from what I understand. Don't know why. Must be bored.
Link Posted: 12/18/2003 5:30:20 PM EDT
Originally Posted By trachnload: I may be an AR-15 newbie, but I think I can help you here. First, E=mc^2 is *not* relativity. It's mass-energy equivalence (and how Star Trek's antimatter engines work). Here's an oversimplified way of looking at relativity. You are driving a school bus toward me at, say, [red]30[/red] mph. I'm standing on the ground a mile away (this is important later). You turn on your headlights. How fast does the light travel from your headlights to my eyes? From elementary school science, we know that light travels 186,000 miles per second. (We'll neglect the "in vacuum" part of the speed.) So this means that the light from the headlights is travelling 186,000 miles per second PLUS 30 miles per hour, right? We'll answer that in a minute. First, let's consider something a little easier to work with. Let's look back into the bus (which is moving along the ground at [red]30[/red] miles an hour) where the kids are. Two kids have stolen the school nerd's shoes. A kid at the back of the bus throws them to his friend at the front of the bus. How fast did he throw the shoes? It depends - and not just on the kid's arms. From what "frame of reference" are you measuring the shoes' speed? Since you're on the bus, you'll probably use the bus as your frame of reference. We'll say that the shoes fly down the bus at 50 miles an hour, RELATIVE to the bus. But relative to me (remember me, standing a mile away on the ground), they're moving 50 mph (from the throw) PLUS [red]60[/red] mph (because the bus is moving relative to me). Now grasp your hat and hold it tightly, because I'm gonna blow your mind. Relativity says that light (electromagnetic radiation of any kind, actually) does not do what we just described. [blue]The speed of light is constant in all frames of reference, according to theory. So the light from your headlights (remember them) DOES NOT move at 186,000 miles per second PLUS 30 mph. It moves at 186,000 miles per second no matter where you are or how fast you're moving.[/blue] Let's pretend that the nerd's shoes behave the way light does in this theory. This means that the shoes move at 50 mph relative to the bus (and to you, the driver). It also means that they move at 50 mph relative to me (in another frame of reference, specifically on the ground). The only way that this can physically happen is if time moves at different speeds in different frames of reference. In our example, the only way for the shoes to move at 50 mph relative to me is if time moves faster for me than for you on the bus. I understand that there is some experimental evidence for this, but opinions may vary. That's the short (?) answer. Hope it helps.
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Are the red highlights something I'm missing? Can you explain the red shift in this context?
Link Posted: 12/18/2003 5:34:01 PM EDT
Relativity is simple. Explain spooky action at a distance or anti-reality!
Link Posted: 12/19/2003 5:02:06 AM EDT
Originally Posted By Axel: Are the red highlights something I'm missing? Can you explain the red shift in this context?
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Oh, yes. Strike the 60 mph right before I told you to "grasp your hat" and make it 30 mph. These are schoolchildren, after all. (Just a typo.) Redshift is a different effect. Put simply, it's the Doppler effect with light instead of sound. ("What's the Doppler effect?") The Doppler effect is why a car horn changes pitch when it drives past you. Basically, if the source of a wave (sound, light, a boat's wake) is moving toward or away from you, then the sound waves will be compressed or extended, raising or lowering the frequency (pitch). An interesting side effect of this effect is the sonic boom. When an object moves faster than the speed of sound in whatever it's moving through, the sound energy "piles" up at the front, since it can't move any faster. The energy "escapes" to the sides. Here's a link: http://library.thinkquest.org/12228/Page5.html This is why "subsonic" bullets are quieter. A "supersonic" bullet makes a small sonic boom as it travels. Hope this helps.
Link Posted: 12/19/2003 5:26:31 AM EDT
[Last Edit: 12/19/2003 5:27:39 AM EDT by TUMOR]
It is focused on the factor 1/(1-(V^2/C^2)) With V = Velocity of the subject frame of reference. and C = Speed of Light
Link Posted: 12/19/2003 7:12:29 AM EDT
Originally Posted By SGTIMAK: So what happens when you're moving at or faster than the speed of light and turn on the headlights? edited: Is that when you see the "Star Wars jump to light speed" scene with the stars and everything getting stretched out and distorted?
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Nobody knows for sure. Theories abound, in varying degrees of...believability. You're talking cutting-edge physics, and the folks here who've just completed Quantum finals would be far more able to discuss them.
Link Posted: 12/19/2003 7:29:36 AM EDT
Without getting into any math, here's a summary of special & general relativity: Special relativity is no big deal, really. There were several people working on the same idea when Einstein came up with it. The idea is this:
The laws of physics are the same in an inertial reference frame
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"Inertial reference frames" are frames (frame = imaginary reference point in space) that are not accelerating with respect to each other. They can have a constant velocity relative to each other. As mentioned above, one consequence is that the same "ray" of light will have the same speed in both frames, regardless of the relative speed of the 2 frames. General relativity is the shit. If Einstein hadn't come up with this, we [i]still[/i] might not have the theory. It says:
The laws of physics are the same in [i]any[/i] reference frame
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Now this is neat stuff. One of the easiest to understand consequences of general relativity is that there is no difference between inertial mass and gravitational mass. WTF does that mean? Inertial mass is the way a body resists a change in velocity. If you're going to push on a refrigerator that's not moving, you're going to have to put some work into it to give it a non-zero velocity. That's because of the inertial mass. Gravitational mass is gravitational "charge". Just like two objects that have opposite electric charges are attracted to each other by electrostatic force, two objects with gravitational mass are attracted to each other by gravity. To the layman, it seems pretty obvious that these are the same thing. Mass is mass is mass, right? The problem is that there was no way to prove it before General Relativity. Consider these two cases: You're on an amusement park ride, and you are pushed back into your seat as it accelerates. You're sitting in your chair, and you're pushed down into it by gravity. General relativity says that these are the same phenomenon. They seem like very different sources of force, but in Gen Rel, they are different maninfestations of the same thing. For example, if you were locked in a box, you could not tell whether the "gravity" you were feeling was due to acceleration or a "real" gravity field.
Link Posted: 12/19/2003 7:34:39 AM EDT
Originally Posted By SGTIMAK: So what happens when you're moving at or faster than the speed of light and turn on the headlights?
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First point: You can't go "at or faster than the speed of light". [;)] As any object with weight starts getting close to the speed of light, its effective mass increases. It goes toward infinity as you approach the speed of light. If you have a (near-)\infinite mass, you need a (near-)infinite source of energy to keep accelerating. Pretty soon, you will have used up all the energy in the universe, and you still won't have reached the speed of light. Second point: Say you're close to the speed of light. The light coming out of your headlights will look [i]to you[/i] like it's going the speed of light. To someone standing still, it will [i]also[/i] look like it's going to speed of light. (It won't be your velocity + the speed of light.)
Link Posted: 12/19/2003 8:06:44 AM EDT
Originally Posted By fizassist: First point: You can't go "at or faster than the speed of light".
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Well...technically that is incorrect. Modern physics says that you can't go faster than the speed of light IN A VACUUM. Cerenkov radiation (the blue glow that you see in reactor cores) is caused by beta particals traveling faster than the speed of light IN WATER. You are correct with everything else though...just had to be a nit picker.
Link Posted: 12/19/2003 8:32:47 AM EDT
Excellent explanation from trachnload. I would also say in a simpler (but probably more confusing) way that while in our ordinary low-speed world, space and time are (or at least seem to be) absolute and speed is relative, when it comes to speeds near the speed of light, it is speed that is absolute and space and time are realitive.
Originally Posted By SGTIMAK: So what happens when you're moving at or faster than the speed of light and turn on the headlights? edited: Is that when you see the "Star Wars jump to light speed" scene with the stars and everything getting stretched out and distorted?
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As fizassist said, travelling at or faster then the speed of light is impossible, according to all the physics we know. It's a paradox, according to the theory. Time on the bus slows down (and length in the direction of travel changes) such that the headlight beam always appears to be traveling away at the speed of light. But that doesn't make sense if the bus could travel at the speed of light. Time would have to go backwards or the length of the bus would be negative for the headlight to appear to move at the speed of light (or both). This doesn't make sense, so nothing can go faster then the speed of light I have never heard of this Cerenkov radiation thing, but Beta particles are electrons, and electrons don't generally travel even at the speed of light. Also, the speed of light slows down in matter, such as in air or water. As far as I know, nothing in the known universe can ever travel faster then the speed of light in a vacum. And, of course, Star Wars is fictional. Nothing seen there neccesarily applies to real life.
Link Posted: 12/19/2003 8:41:55 AM EDT
Mace, Thanks - I appreciate the compliment. Cerenkov radiation is basically a sonic boom, but with light instead of sound. It happens when something exceeds the speed of *light* in a given medium. The excess energy "piles" up in front, and the shock wave generated manifests itself as EMR instead of sound. The electrons in a nuclear reactor get accelerated like this, I believe. If you're ever at Penn State, see if you can tour the Brezeale Nuclear Reactor (it's there for the Nuclear Engineers to play with, basically). Post 9/11, who knows, but I toured it a few years ago. There's a beautiful blue glow around the reactor core (which is under about 40 feet of water to absorb radiation) - this is Cerenkov radiation. Part of their tour introduces you to some common materials which are radioactive (cinder blocks and lantern mantles are VERY hot... :-) ).
Link Posted: 12/19/2003 8:44:23 AM EDT
It's all relative.
Link Posted: 12/19/2003 9:08:07 AM EDT
One of my favorite books on the subject, [url=http://www.amazon.com/gp/reader/0679725105/ref=sib_dp_pt/103-2336376-6553449?tag=vglnk-c102-20#reader-link]Einstein for Beginners[/url]. It's basically a glorified comic book which, I think, does a pretty good job illustrating relativity. I also find it interesting that if a person were traveling near the speed of light, besides gaining mass they also become flat (two dimensional. I find it more amazing that there are so many people in the world who are obviously traveling near the speed of light...two dimensional fat-asses.
Link Posted: 12/19/2003 9:28:35 AM EDT
My Grandmother had a theory of special relativity. She said: [b]Where there's a will, There's relatives![/b]
Link Posted: 12/19/2003 3:49:58 PM EDT
Originally Posted By TexasEd:
Originally Posted By fizassist: First point: You can't go "at or faster than the speed of light".
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Well...technically that is incorrect. Modern physics says that you can't go faster than the speed of light IN A VACUUM.
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That's why I said [i]the[/i] speed of light, not [i]a[/i] speed of light. [;)] Yep, Cherenkov radiation is cool stuff. We use it to detect high momentum particles from nuclear collisions. Basically, you catch the high momentum particles in something with a high index of refraction (low "speed of light") and record the cherenkov light coming out in cones. The opening angle of the cone is directly related to the velocity of the particle. If you know its momentum from another detector, you can then find the mass (which uniquely determines the type of particle).
Link Posted: 12/19/2003 5:59:37 PM EDT
I am sure glad I changed majors... I wanted to be a Nuclear Physicist since I was 9 up to the age of 19. Explaining the old theories vs. the new theories make my head hurt. Anybody remember the tachyons the faster than light particles theorized in the 1970's?
Link Posted: 12/19/2003 8:53:28 PM EDT
Screw relativity. I wanna know the particulars of the TOE.
Link Posted: 12/19/2003 9:41:56 PM EDT
Originally Posted By TWIRE: One of my favorite books on the subject, [url=http://www.amazon.com/gp/reader/0679725105/ref=sib_dp_pt/103-2336376-6553449?tag=vglnk-c102-20#reader-link]Einstein for Beginners[/url]. It's basically a glorified comic book which, I think, does a pretty good job illustrating relativity. I also find it interesting that if a person were traveling near the speed of light, besides gaining mass they also become flat (two dimensional. I find it more amazing that there are so many people in the world who are obviously traveling near the speed of light...two dimensional fat-asses.
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Yeah, I read that book! I was trying to search on Amazon but couldn't remember the exact title. That's a good book that will give you a good basic understanding of the theory of relativity.
Link Posted: 12/19/2003 9:49:24 PM EDT
Stephan Hawkings illstrated "A brief history of time" is rather nice too. I hate math and he did a fairly good job at explaining it, I felt.
Link Posted: 12/19/2003 10:12:09 PM EDT
[Last Edit: 12/19/2003 10:24:23 PM EDT by Greenhorn]
I started thinking about this, and thought of a problem. It's 2:00 AM so maybe that's why I can't come up with an answer, but here it is: It doesn't matter if the spaceship that's traveling at near light speed is going away from you or toward you, the time dilation will be the same . . . as far as I know. To the person on the ship, the person on the ground would quickly age and die (depending on how close to lightspeed the guy in the spaceship is). All the while, your headlights are shining light at him, and to you the light is traveling at normal lightspeed. So, if time is traveling extremely fast for the stationary guy as seen by the guy in the spaceship, this would mean that the light would be extremely red-shifted to the stationary guy since more time is passing for him between each wave of light than for the guy in the spaceship. But how could it be red-shifted if the guy is traveling TOWARD the stationary guy? The light should be blue-shifted to him! But if the light WAS blue-shifted, the stationary guy would be getting more light energy than the spaceship guy is putting out, which is impossible. Does any of this make sense? ??? Or maybe, for something traveling relative to you (let's pick toward you for explanation's sake), the faster it goes (toward you) the more blue-shifted the light will be, but there won't be much time dilation, until a certain point is reached, where time dilation will rapidly increase and blue-shift will reverse preportionally? [whacko]
Link Posted: 12/19/2003 11:09:34 PM EDT
Originally Posted By Greenhorn: I started thinking about this, and thought of a problem. It's 2:00 AM so maybe that's why I can't come up with an answer, but here it is: It doesn't matter if the spaceship that's traveling at near light speed is going away from you or toward you, the time dilation will be the same . . . as far as I know. To the person on the ship, the person on the ground would quickly age and die (depending on how close to lightspeed the guy in the spaceship is). All the while, your headlights are shining light at him, and to you the light is traveling at normal lightspeed. So, if time is traveling extremely fast for the stationary guy as seen by the guy in the spaceship, this would mean that the light would be extremely red-shifted to the stationary guy since more time is passing for him between each wave of light than for the guy in the spaceship. But how could it be red-shifted if the guy is traveling TOWARD the stationary guy? The light should be blue-shifted to him! But if the light WAS blue-shifted, the stationary guy would be getting more light energy than the spaceship guy is putting out, which is impossible. Does any of this make sense? ??? Or maybe, for something traveling relative to you (let's pick toward you for explanation's sake), the faster it goes (toward you) the more blue-shifted the light will be, but there won't be much time dilation, until a certain point is reached, where time dilation will rapidly increase and blue-shift will reverse preportionally? [whacko]
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Red/blue shift and special relativity are separate beasts. Something coming toward you is always blue-shifted; something moving away is always red-shifted. Special relativity introduces time dilation, which can somewhat modify the magnitude (not the sign!) of the red/blue shift at relativistic velocities. Special relativity also says that you cannot say whether you are moving toward the "stationary" observer or the "stationary" observer is moving toward you. That means that the "oncoming" observer will always be blueshifted relative to you, regardless of time dilation.
Link Posted: 12/20/2003 12:34:03 AM EDT
Originally Posted By TexasEd: Well...technically that is incorrect. Modern physics says that you can't go faster than the speed of light IN A VACUUM.
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That's only partly correct. Modern physics says that massive particles cannot travel [i]equal to[/i] the speed of light in a vacuum ([i]c[/i]). It says nothing about particles being unable to travel at speeds greater than [i]c[/i]. In fact, superluminous particles are the basis for one of the two main theories for black-hole degeneration. Basically, if you have a particle going near [i]c[/i] in a very confined space, that whole quantum uncertainty thing says that it is possible for it to suddenly and discreetly jump from .9996[i]c[/i] to 1.0003[i]c[/i] without ever going any of the speeds in between. Now, this just isn't an option in "normal" relativity physics, though, because "normal" relativity physics deals with large massive objects rather than quantum ones. And a "normal" massive object simply will not exhibit such a quantum change in velocity. That, and, it would still take an enormously large amount of energy to get anything significant to .9996[i]c[/i] or faster. And then things get fuzzy in the superluminous realm. Some sets of equations get complex components while others don't. For example, using Einstein's Special Relativity equations for velocity, you travel in a complex time direction (a+b[i]i[/i]). However, when you use Einstein's equations for momentum, you get negative time! So which is it? Do superluminous particles go backwards in real time, or do they travel forward in real time and also move along an imaginary time axis? Last I've read, we don't know.
Link Posted: 12/20/2003 6:44:43 AM EDT
Try doing a google search on "pole barn" sometime. You'll discover a paradox of relativity. [:)]
Link Posted: 12/20/2003 7:02:39 AM EDT
One very interesting note on modern physics. If you read the earlier post comparing acceleration and gravity being equivalent, it seems no one can explain why. Gravity is taken as a given and no one know WHY gravity exists. They say if something has mass it exerts gravitational force.... The big question is WHY does it do that. No one has the answer and I suspect that answer would answer a lot of other questions about the universe and its workings.
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