A-wal Posted October 14, 2012 Author Share Posted October 14, 2012 Did you copy and paste that? Just stating what I'm trying to refute doesn't weaken my case, that's not how it works. I've come up with a much better explanation. If you want to refute it then tell me why the standard explanation is better. Good luck. A geodesic is a straight line. Time never stops from anyones erspective, even in the standard version of general relativity, it just keeps slowing down from the perspective of other observers. How could an object reach the event horizon when it can't ever be reached from any other objects perspective, no matter how close they are? Think about it. You're right that the rope paradox is the same as one object, the rope just makes it easier to visualise. I didn't say that anyone supports it, I said that there hasn't been an attempt to refute the content, not by anyone who knows what they're talking about anyway. It's bullet proof. I didn't know those three had read this thread. That's encouraging, they couldn't find any faults with it either. -1 Link to comment Share on other sites More sharing options...
MigL Posted October 14, 2012 Share Posted October 14, 2012 If I say unicorns are pink, and no one refutes it ( either because there are no unicorns so no one knows their colour, or because its a dumb assertion ), does that make unicorns real and pink ?? That's the logic you just used to 'slap me down'. It must be bulletproof. Link to comment Share on other sites More sharing options...
A-wal Posted October 15, 2012 Author Share Posted October 15, 2012 Is that the best you can do? What I used to bitch slap you was the fact that you thought that following a geodesic is somehow different from following a straight when that exactly what geodesic means and that time never stops from the perspective of any outside observer watching an object approaching an event horizon, it just continually slows in exactly the same way it does when watching an object accelerate towards the speed of light. They could never actually reach the event horizon, in the same way the accelerating object could never reach a relative velocity of the speed of light. I've thrown down both gauntlets in this thread and then some. If they could find fault with it then they would have. They'd love to rip this to shreds but they can't because they know I might be right. Your comment was stupid. Unicorns are definitely not pink! Try again, and try harder. I feel like a cat toying with a mouse. -2 Link to comment Share on other sites More sharing options...
ydoaPs Posted October 15, 2012 Share Posted October 15, 2012 If it can't be explained without resorting to mathematics then whoever's explaining it doesn't truly understand it That's almost the exact opposite of true. 1 Link to comment Share on other sites More sharing options...
MigL Posted October 15, 2012 Share Posted October 15, 2012 (edited) You keep bringing up the far away observer frame of reference and claim that since time comes to astandstill in THAT frame, it must be what actually happens, ie in every frame. You can't grasp the concept that GR is frame independant because there is no absolute frame that determines what actually happens. There is no background frame or stage ( absolute time or absolute space ) upon which events happen. The far away observer only sees reflected light from the object falling in the black hole. Light is a vibration of electric and magnetic fields with a time dependance. The light moving away from the vicinity of the event horizon ( if it still can ) has its time base stretched towards infinity ( just like you claim ) so that light eminating from the event horizon has its time base stretched to infinity and so has no energy left and cannot be seen, ie its black !!! In the objects local frame things are vastly different. There is no time dilation and the object proceeds through the event horizon on its way to meet up with the possible singularity. There are numerous books where this is demonstrated mathematically by people like Oppenhimer. Novikov, Vald'ovich, Wheeler and the previously mentioned Thorne , Hawking and Penrose. Why don't you try reading some of them. Is it any wonder you have no posts in the physics or math forums, but only in speculations ? That's where the kooks and cranks reside, while the rest of us just check in every once in a while to make sure you guys don't hurt your brains. Yeah, you did bitch slap me; What else would I expect from a bitch. Edited October 15, 2012 by MigL Link to comment Share on other sites More sharing options...
A-wal Posted October 15, 2012 Author Share Posted October 15, 2012 That's almost the exact opposite of true. How so? The mathematics stays the same and can be memorised without any understanding of what it represents. Describing in your own words proves that's you understand what the maths represents. You keep bringing up the far away observer frame of reference and claim that since time comes to astandstill in THAT frame, it must be what actually happens, ie in every frame. I already told that time does NOT come to a standstill! I'm well aware that relativity is frame independent thank you, that's one of the main reasons why I love it so much. It doesn't matter which frame of reference you use! An object can't reach an event horizon from any frame in any valid coordinate system (one that covers the entire manifold). You can't grasp the concept that GR is frame independant because there is no absolute frame that determines what actually happens. LOL!!! There is no background frame or stage ( absolute time or absolute space ) upon which events happen. That's from special relativity! Is it any wonder you have no posts in the physics or math forums, but only in speculations ? That's where the kooks and cranks reside, while the rest of us just check in every once in a while to make sure you guys don't hurt your brains. You might want to check the relativity thread. Yeah, you did bitch slap me; What else would I expect from a bitch. (: 'I'm not, you are.' This is like being back at school. Let me guess, I should know. How old are you? Link to comment Share on other sites More sharing options...
Phi for All Posted October 16, 2012 Share Posted October 16, 2012 Yeah, you did bitch slap me; What else would I expect from a bitch. (: 'I'm not, you are.' This is like being back at school. Let me guess, I should know. How old are you? ! Moderator Note No more personal attacks or you both get a time-out. Link to comment Share on other sites More sharing options...
uncool Posted October 16, 2012 Share Posted October 16, 2012 I already told that time does NOT come to a standstill! I'm well aware that relativity is frame independent thank you, that's one of the main reasons why I love it so much. It doesn't matter which frame of reference you use! An object can't reach an event horizon from any frame in any valid coordinate system (one that covers the entire manifold). Err. There is no guarantee that the manifold is simply connected, which is what is required for there to be a coordinate system which covers the entire manifold. As such, to give it the epithet of "valid" seems inappropriate, as there are several relevant manifolds where (according to your naming) there is no "valid" coordinate system. That's from special relativity! Which is a special case of general relativity. =Uncool- Link to comment Share on other sites More sharing options...
ydoaPs Posted October 16, 2012 Share Posted October 16, 2012 How so? The mathematics stays the same and can be memorised without any understanding of what it represents. Describing in your own words proves that's you understand what the maths represents. Mathematics is a language just like any other except it's better suited for the task. You not understanding it doesn't mean it doesn't carry as much understanding as English or French. In fact, it carries more. You tell me in English how electric fields and magnetic fields relate. I guarantee the Maxwell Equations carry more understanding than your English. If you can't do the math, you don't understand what's going on. 2 Link to comment Share on other sites More sharing options...
Ronald Hyde Posted October 16, 2012 Share Posted October 16, 2012 When Faraday wrote up the results of his experiments in electromagnetism he used both words and pictures, but the phrases that he used could readily be converted into differential equations, which is of course what Maxwell did with them. And Heaviside came along and simplified Maxwell's notation, which is what we use today. And you do need words to place the mathematical concepts in a proper context, you can't just guess what they apply to. So if you insist upon using words only, make sure that someone can translate them into math. Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 Err. There is no guarantee that the manifold is simply connected, which is what is required for there to be a coordinate system which covers the entire manifold. As such, to give it the epithet of "valid" seems inappropriate, as there are several relevant manifolds where (according to your naming) there is no "valid" coordinate system. There is one manifold, it's called space-time. The disjointed coordinates systems into different manifolds is a product of an incorrect description of space-time. The Schwarzschild coordinates for example do cover the entire manifold because space-time stops at the event horizon. Which is a special case of general relativity. I hate it when people say that. General relative is nothing but a failed attempt to reformulate special relativity. A special case of general relativity. Mathematics is a language just like any other except it's better suited for the task. You not understanding it doesn't mean it doesn't carry as much understanding as English or French. In fact, it carries more. You tell me in English how electric fields and magnetic fields relate. I guarantee the Maxwell Equations carry more understanding than your English. If you can't do the math, you don't understand what's going on. When Faraday wrote up the results of his experiments in electromagnetism he used both words and pictures, but the phrases that he used could readily be converted into differential equations, which is of course what Maxwell did with them. And Heaviside came along and simplified Maxwell's notation, which is what we use today. And you do need words to place the mathematical concepts in a proper context, you can't just guess what they apply to. So if you insist upon using words only, make sure that someone can translate them into math. I know how useful maths is for describing reality. It's not open to interpretation like words are. It's as concise as you can get. That doesn't change the fact that if I say that the way time dilates and length contracts from the perspective of two objects with different relative velocities can be worked out by working out how far the energy has to travel and how long it takes to do it taking into account that energy always propagates through space-time at a constant velocity relative to any inertial object, then I think that shows a lot more understanding than regurgitating a bunch of equations. I do understand what's going on. I describe it simply in the relativity made simple thread. Besides, all the mathematics I'm describing here comes from special relativity anyway. Link to comment Share on other sites More sharing options...
swansont Posted October 16, 2012 Share Posted October 16, 2012 I hate it when people say that. General relative is nothing but a failed attempt to reformulate special relativity. Yeah, all those experiments that don't match the predictions are simply a travesty. All none of them. 1 Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 Can I please have an example of an experiment that matched the predictions of general relativity, but at the same time didn't match the predictions of treating gravitation acceleration due to mass as the equivalent of acceleration caused by energy? Link to comment Share on other sites More sharing options...
uncool Posted October 16, 2012 Share Posted October 16, 2012 (edited) There is one manifold, it's called space-time. The disjointed coordinates systems into different manifolds is a product of an incorrect description of space-time. The Schwarzschild coordinates for example do cover the entire manifold because space-time stops at the event horizon. For that specific spacetime. Read what I said carefully - I said that there was no guarantee that a single coordinate frame can cover the entire manifold. For example, consider a 4-torus with the obvious quotient metric. No curvature, no mass, but still there is no single coordinate frame that covers the entire manifold in a 1-1 manner. I hate it when people say that. General relative is nothing but a failed attempt to reformulate special relativity. A special case of general relativity. You may get angry, but it's true. =Uncool- Edited October 16, 2012 by uncool 1 Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 (edited) For that specific spacetime. Read what I said carefully - I said that there was no guarantee that a single coordinate frame can cover the entire manifold. For example, consider a 4-torus with the obvious quotient metric. No curvature, no mass, but still there is no single coordinate frame that covers the entire manifold in a 1-1 manner. Okay, but I think that one that doesn't cover the entire manifold is inherently wrong, or at least incomplete and doesn't have anything to offer. You may get angry, but it's true. =Uncool- (: That grumpy face wasn't entirely serious. I do get irritated though when people say that, but not angry. I'm not that emotional. Say it's true isn't a very good argument. I know it's supposedly true but I don't think it's very likely to actually be true, not when there's a much simpler explanation. Edited October 16, 2012 by A-wal Link to comment Share on other sites More sharing options...
uncool Posted October 16, 2012 Share Posted October 16, 2012 Okay, but I think that one that doesn't cover the entire manifold is inherently wrong, or at least incomplete and doesn't have anything to offer. Inherently wrong, no. No chart can cover a torus in a 1-1 way. A torus is not simply connected, let alone contractible; only contractible (and hence simply connected) manifolds can be covered by a chart in a 1-1 way. Incomplete, yes - the entire point of a manifold is that it is covered by several charts. That's how a manifold is defined. A circle, for example, needs to be covered by two charts. "Doesn't have anything to offer", no - the coordinates have plenty to offer. In fact, they offer everything about what happens within them. (: That grumpy face wasn't entirely serious. I do get irritated though when people say that, but not angry. I'm not that emotional. Say it's true isn't a very good argument. I know it's supposedly true but I don't think it's very likely to actually be true, not when there's a much simpler explanation. I think you may have mixed up the antecedents here. I was saying that the claim that general relativity is an extension of special relativity is true, not that general relativity is true. =Uncool- Link to comment Share on other sites More sharing options...
swansont Posted October 16, 2012 Share Posted October 16, 2012 Can I please have an example of an experiment that matched the predictions of general relativity, but at the same time didn't match the predictions of treating gravitation acceleration due to mass as the equivalent of acceleration caused by energy? I don't know what the predictions are of "treating gravitation acceleration due to mass as the equivalent of acceleration caused by energy". How does it differ from GR? How is that comparison with GR even valid, given that the stress-energy tensor includes energy? (i.e. it's not just mass) Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 (edited) Inherently wrong, no. No chart can cover a torus in a 1-1 way. A torus is not simply connected, let alone contractible; only contractible (and hence simply connected) manifolds can be covered by a chart in a 1-1 way. Incomplete, yes - the entire point of a manifold is that it is covered by several charts. That's how a manifold is defined. A circle, for example, needs to be covered by two charts. Torus, that's a donut shape isn't it? I wasn't very clear there. What I meant is that any valid coordinate system for describing space-time should be applicable to the whole of space-time. If it stops at an event horizon that that coordinate system predicts that space-time stops at an event horizon. "Doesn't have anything to offer", no - the coordinates have plenty to offer. In fact, they offer everything about what happens within them. (: Yes, I know that. I think you may have mixed up the antecedents here. I was saying that the claim that general relativity is an extension of special relativity is true, not that general relativity is true.I let you off then. (; I don't know what the predictions are of "treating gravitation acceleration due to mass as the equivalent of acceleration caused by energy". How does it differ from GR? How is that comparison with GR even valid, given that the stress-energy tensor includes energy? (i.e. it's not just mass) Well, the rope paradox is one, but that's not easily testable at the moment. Another is that an object using mass to accelerate (free-fall) should experience a Rindler horizon and light in front of them slowing down in exactly the same way as an objects using energy to accelerate. Edited October 16, 2012 by A-wal Link to comment Share on other sites More sharing options...
swansont Posted October 16, 2012 Share Posted October 16, 2012 Isn't "acceleration caused by energy" covered by the equivalence principle? Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 No, the equivalence principle doesn't go far enough. It says they're only equivalent to the first order, I think that's the correct way of saying it. GR describes free-fall as inertial, it's not though. Acceleration caused by energy and acceleration caused by mass really are equivalent. The only difference is that mass pull inwards towards it creating an inwards curvature of space-time, and energy pushes outwards away from it creating an outwards curvature of space-time. Another prediction is that the strength of electro-magnetism is equal to the strength of gravity times the speed of light squared. Link to comment Share on other sites More sharing options...
ydoaPs Posted October 16, 2012 Share Posted October 16, 2012 No, the equivalence principle doesn't go far enough. It says they're only equivalent to the first order, I think that's the correct way of saying it. GR describes free-fall as inertial, it's not though. Acceleration caused by energy and acceleration caused by mass really are equivalent. The only difference is that mass pull inwards towards it creating an inwards curvature of space-time, and energy pushes outwards away from it creating an outwards curvature of space-time. Another prediction is that the strength of electro-magnetism is equal to the strength of gravity times the speed of light squared. And here's why math carries more understanding. Because you know *how much* different things effect each other. Right now, the above quote is nonsense. Do the math, and it's testable. Go ahead and disprove relativity. Give us the correct equation, and apply it and the actual relevant equation to a scenario for which we already have data. Let's see which one is more accurate. Saying "things interact" is handwavy and doesn't tell us at all *how* they interact. Math wins. Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 (edited) I'm not being in the slightest bit "handwavy". You've completely ignored what I'm saying. Using mass to accelerate is the EXACT EQUIVALENT of using energy to accelerate, and all the maths is the same, accept that energy pushes and mass pulls. Edited October 16, 2012 by A-wal Link to comment Share on other sites More sharing options...
ydoaPs Posted October 16, 2012 Share Posted October 16, 2012 I'm not being in the slightest bit "handwavy". You've completely ignored what I'm saying. Using mass to accelerate is the EXACT EQUIVALENT of using energy to accelerate, and all the maths is the same, accept that energy pulls and mass pushes. Opposite signs are not "exactly the same". The math is different. Link to comment Share on other sites More sharing options...
mississippichem Posted October 16, 2012 Share Posted October 16, 2012 (edited) Using mass to accelerate is the EXACT EQUIVALENT of using energy to accelerate, and all the maths is the same, accept that energy pulls and mass pushes. Bold mine Let's see the math then. Do you know how to use LaTeX? If not there is a tutorial available here on site. Edited October 16, 2012 by mississippichem 1 Link to comment Share on other sites More sharing options...
A-wal Posted October 16, 2012 Author Share Posted October 16, 2012 (edited) Opposite signs are not "exactly the same". The math is different. Only slightly, and only in some situations. Read the bit after the last comma. Bold mine Let's see the math then. Do you know how to use LaTeX? If not there is a tutorial available here on site. You can't just take the bits that you've bolded and ignore the rest. It's even in the same sentence. Edited October 16, 2012 by A-wal Link to comment Share on other sites More sharing options...
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