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Calculate the galaxy movement distances in that time  Shouldn't that have been "Calculate the galaxy movement distances" relative to something?
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But that's the problem. To "ask, criticize, throw rocks" I have to stop and think about what is going on. And as I said, I don't really like to have to think. You keep posting things that force me to think to try to come up with good answers. It is easier if people say things that I already know are wrong and all I have to do is point out their errors.
Bill Gill
C is not the speed of light in a vacuum.
C is the universal speed limit.
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I am aware that one should not talk of a straight line without reference to something. However, if a moving object which, in our F of R, we measure as being in uniform motion, relative to something, changes course, relative to that same something, we deem it to have accelerated, relative to that something, and conclude that the object has been influenced by a force. Our conclusion may be erroneous if the motion, and change in motion, are considered relative to some other something in another F of R, but within ours, I think it does not conflict with the laws of relativistic physics. Excellent you have made the connection, always be wary about your frame of reference.
Last edited by Orac; 01/26/15 05:48 PM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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Shouldn't that have been "Calculate the galaxy movement distances" relative to something? Again excellent you have got the issue. If you think hard there is only reference you can use which is energy. That is what your big reply above is trying to say when trying to talk about acceptable frames of reference and relative motions etc. Hopefully you can now join the whole lot together by reading about planks constant. Initially try to skip around the quantum mechanics and follow it's history back into classical physics and the "fixation section" at the end should help with understanding all the connections. http://en.wikipedia.org/wiki/Planck_constantIf you make the connections you should now see you have a complete framework referenced to energy via planks constant but the whole system has a small issue can you see what it is Problem Hint: Read the significance of value section carefully.
Last edited by Orac; 01/26/15 05:49 PM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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We are getting some good stuff here, Orac.
A nagging thought at the back of my mind says: the original subject was gravity, we seem to be talking largely about quantum scale objects. Do we have a quantum theory of gravity? I understand not.
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I am not here to give you an answer, you need to work out an answer for yourself that makes sense to you. I don't like the idea of standard consensus solutions in science As I said you can ignore the QM stuff and look purely at the classical physics side. Planck and Einstein create QM in trying to solve part of the puzzle but pretend you are in 1900 and look at the data you have in purely classic terms and stay with gravity. Whether gravity is based in or with QM is not important at this stage we are looking at the classical situation. Let me throw you a hint to ponder. At the plank scale in classical terms space must be flat, you see this happen when you look at the earth beneath your feet. No matter what curvature space may or may not have if you reduce the section small enough the curvature disappears. The second point in relativity terms is your frame of reference gets very compact. Sabine Hossenfelder deals with this is a technical way in this article ( http://backreaction.blogspot.com.au/2013/04/black-holes-and-planck-length.html). I want you to think about this part of her statement and see if you can work out what she means and if you agree with her. The Planck length appears in General Relativity as a coupling constant. It couples the curvature to the stress-energy tensor. Most naturally, one expects quantum gravitational effects to become strong, not at distances close by the Planck length, but at curvatures close to one over Planck length squared. (Or higher powers of the curvature close to the appropriately higher powers of the inverse Planck length respectively.) The curvature is an invariant. This statement is therefore observer-independent. Unfortunately wikipedia doesn't really deal with the subject well but it does help you understand why this question is the most important with what you are pondering and I encourage you to think more about it. http://en.wikipedia.org/wiki/Planck_scaleEdit: Bit of squirreling around and thanks to NASA's education outreach try reading this http://arxiv.org/pdf/1001.1205v1.pdf
Last edited by Orac; 01/27/15 02:08 AM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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Orac, I've not lost sight of the fact that I have not responded to your last post. Hope to get to it soon.
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If you are still interested in going on I will give you another interesting recent experiment by Martin Ringbauer et al https://medium.com/the-physics-arxiv-blo...ne-185a7cc9bd11Full paper:http://arxiv.org/pdf/1501.05014v1.pdfIt is a really interesting experiment on links between GR, QM and causality and worth reading.
Last edited by Orac; 02/04/15 01:21 AM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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Just get round to following links. Started with: https://medium.com/the-physics-arxiv-blo...ne-185a7cc9bd11 The first thing that strikes me is this: “In the early 90s, for example, cosmologists showed that a billiard ball entering a wormhole that leads to a closed time-like curve must always meet its older self coming out of the wormhole. What’s more, the resulting collision always prevents the ball entering the wormhole in the first place. In other words, the billiard ball would simply bounce off the entrance to a closed time-like curve.” Isn’t that just replacing one paradox with another? If the ball cannot enter the closed time-like curve, how did its older self get in there in the first place? I can answer that in terms of my "infinity theory", but who's going to accept that? One would expect clever computer stuff from David Deutsch, for whom I have great respect, but I sometimes feel he blurs the line between computer programs and reality. Are you familiar with his ideas on the Omega Point Theory? I don’t know enough about computers to know how a nondeterministic algorithm reflects reality, but I suspect it would be only loosely. To my very non-technical mind, it seems as though this experiment uses a simulated pair of entangled photons and treats them as though they were one real photon. Doesn’t that have echoes of claims relating to teleportation? Don’t think I am knocking the work. Not only am I not qualified to do that, but I am fascinated by any work on time/loops/travel, and am keen to understand as much as possible about them.
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Isn’t that just replacing one paradox with another? If the ball cannot enter the closed time-like curve, how did its older self get in there in the first place? I can answer that in terms of my "infinity theory", but who's going to accept that? As discussed before sometimes looking carefully at the question and changing it tells you things Are you familiar with his ideas on the Omega Point Theory? Yes but there is a problem we discussed it above no actual singularity can exist because of the planck distance and uncertainty principle, you looked at the QM evidence and experiments. Even in string theory which can generally do anything you have to do some pretty interesting things to allow a singularity. The idea and theory is therefore falsified unless you can somehow restore a singularity and so add that to the theory scrap heap like many others. Remember the only indication for a singularity is indicated from GR and that is fairly fuzzy Matt does a reasonable job in http://profmattstrassler.com/2014/03/21/did-the-universe-begin-with-a-singularity/ To my very non-technical mind, it seems as though this experiment uses a simulated pair of entangled photons and treats them as though they were one real photon. Doesn’t that have echoes of claims relating to teleportation? So are you and your father one entity or two. As far as we know there are only a limited number of humans that spontaneously appeared out of thin air and the same with entangled particles The dependency between the existence is what is interesting.
Last edited by Orac; 02/06/15 03:46 PM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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Yes but there is a problem we discussed it above no actual singularity can exist... As I recall, Deutsch’s idea did not involve a singularity. I’ve succeeded in finding a quote from him. He treats the survivors at the omega-point as the ultimate virtual reality rendering. He regards them as computers, into which the last remaining intelligent beings in the Universe have downloaded their intellectual “essence”. He describes the dying moments of the Universe, according to the omega-point theory, as follows: “The key discovery of the omega-point theory is that a class of cosmological models in which, though the universe is finite in both space and time, the memory capacity, the number of possible computational steps and the effective energy supply are all unlimited. This apparent impossibility can happen because of the extreme violence of the final moment of the universe’s Big Crunch collapse. Spacetime singularities, like the Big Bang and the Big Crunch, are seldom tranquil places, but this one is far worse than most. The shape of the universe would change from a 3-sphere to the three-dimensional analogue of the surface of an ellipsoid. The degree of deformation would increase, and then decrease, and then increase again more rapidly with respect to a different axis. Both the amplitude and frequency of these oscillations would increase without limit as the final singularity approached, so that a literally infinite number of oscillations would occur even though the end would come within a finite time. Matter as we know it would not survive: all matter, and even the atoms themselves, would be wrenched apart by the gravitational shearing forces generated by the deformed spacetime. However, the shearing forces would also provide an unlimited source of available energy, which could in principle be used to power a computer. How could a computer exist under such conditions? The only ‘stuff’ left to build computers with would be elementary particles and gravity itself, presumably in some highly exotic quantum states whose existence we, still lacking an adequate theory of quantum gravity, are currently unable to confirm or deny. (Observing them experimentally is of course out of the question.) If suitable states of particles and the gravitational field exist, then they would also provide an unlimited memory capacity, and the universe would be shrinking so fast that an infinite number of memory accesses would be feasible in a finite time before the end.” Thus, in the F of R of the “survivors”, the singularity would never arrive.
Last edited by Bill S.; 02/07/15 06:40 PM.
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That is a small amount of the energy required to create the mass, wherever that came from, will be expended in creating the warp. Of course for existing masses no further energy expenditure would be required to maintain the warp. I’m not sure I can agree with the second sentence. Consider the flip-side of your thought experiment. There is a mass distorting spacetime, if that mass suddenly vanished, spacetime would revert to its original configuration. Spacetime must be trying to revert all the time that the presence of the mass is keeping it distorted. If you compress a spring, and hold it in the compressed state you will probably soon become aware that you are expending energy, just holding it there. Would the same not apply to a mass holding spacetime in a distorted form?
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I’m not sure I can agree with the second sentence. Consider the flip-side of your thought experiment. There is a mass distorting spacetime, if that mass suddenly vanished, spacetime would revert to its original configuration. Spacetime must be trying to revert all the time that the presence of the mass is keeping it distorted. If you compress a spring, and hold it in the compressed state you will probably soon become aware that you are expending energy, just holding it there. Would the same not apply to a mass holding spacetime in a distorted form?
When you compress the spring and hold it there the energy you are expending is not really being used to hold the spring compressed. The energy is being used by your muscles to maintain the position. If you substitute a clamp for your hand then you will realize that there is no extra energy required because the system is in a state of balance. It will be the same for a static mass in a static universe. Adding or removing the mass will cause a ripple to move outward from the location of the mass. The ripple will carry energy that comes from the total energy of the mass and the gravitational field. For a realistic universe with many masses of course everything will be moving, so the gravitational field will be rippling all the time. Think of stirring water. There will be ripples. The energy to create the ripples comes from the motion of whatever you use to stir it. In the case of a mass in a gravitational field the energy carried away by the ripples comes from the motion of the mass. For most objects, such as planets, the ripples will be so small that they are, for all practical purposes, undetectable. The energy loss, and thus a change in the velocity of the mass, can be calculated. It takes a long time for a planet to lose a significant amount of energy to gravitational ripples. Bill Gill
C is not the speed of light in a vacuum.
C is the universal speed limit.
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Slowly cut through your clamp. As you do so, the spring will first deform, then break the clamp. That spring pressure has been there all the time; you don’t increase it by cutting the clamp. Alternatively, consider that while the spring is being held in tension its molecules readjust; energy is lost as heat and the shape to which the spring would "return" changes. Could it be that anything like that would happen to spacetime if it is held in a distorted shape for a very long time? Just a “what if”.
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Slowly cut through your clamp. As you do so, the spring will first deform, then break the clamp. That spring pressure has been there all the time; you don’t increase it by cutting the clamp. But there is no energy expended by the clamp when it is holding the spring. In the mass/space system there is no way to cut the clamp. Alternatively, consider that while the spring is being held in tension its molecules readjust; energy is lost as heat and the shape to which the spring would "return" changes. Could it be that anything like that would happen to spacetime if it is held in a distorted shape for a very long time?
Again, the energy lost is for the specific case of the spring and clamp system. That is not an isolated system. In the thought experiment with just space and one mass Spacetime is the whole system, there isn't any place for energy to be lost to. Bill Glll
C is not the speed of light in a vacuum.
C is the universal speed limit.
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In the mass/space system there is no way to cut the clamp. That’s true. However, suppose the mass is ice, and it can somehow be vaporized. As it goes, spacetime will revert to its normal configuration. Energy must be involved in this change. So, is it true to say that spacetime in its distorted form has potential energy that is converted to kinetic energy as its shape changes? Thus, distorting spacetime has something in common with picking up a stone in a gravitational field, and placing it on a shelf. I.e. there is an exchange of energy while the stone is being lifted, and, again, if it is pushed off the shelf so that it falls; but there is no energy exchange while it sits on the shelf.
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Well, as the ice dissolves the configuration will change. But the mass will remain the same. It will just be spread out. The change in energy will just be converted into the energy of motion as the water molecules move away from the location of the ice cube. The dip in the rubber sheet will get smaller, but a lot more dips will appear, one for each molecule. They will be small dips, but they will be there. And of course the interactions among the molecules will become very complex. It won't be as simple as an ice cube on a rubber sheet.
Once again remember that the bowling ball on a rubber sheet is only an analogy. The analogy helps us visualize what is happening, but the reality is quite a bit more complex than is shown in the analogy.
Bill Gill
C is not the speed of light in a vacuum.
C is the universal speed limit.
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Thanks Bill. I think I have the necessary bits for the jigsaw; all I have to do now is put them together to see what the picture looks like. All I have to do then is see if I can link it to Orac's QM. That might be more fun than anyone should have.
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