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  4. If I give an object some potential energy, does its mass increase?
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If I give an object some potential energy, does its mass increase?

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Offline Raghavendra

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If I give an object some potential energy, does its mass increase?
« Reply #40 on: 09/08/2009 09:21:07 »
No.. You can't increase the mass of a plate.
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #41 on: 10/08/2009 15:02:40 »
Quote from: Farsight on 08/08/2009 08:45:44
Quote from: VernonNemitz on 06/08/2009 03:14:02
So, if we consider that the proton and electron lose mass as they approach each other, converting it to kinetic energy that will be radiated when they coalesce into a hydrogen atom, then it is necessary for the proton to lose 1836 times as much mass as the electron, during the event, for both to have the same mass ratio at the end of the event, as they had at the beginning.
This isn't right. The kinetic energy is 1/2mv2, and if the larger mass is moving slower than the smaller mass the ratios are skewed.
Do not confuse the kinetic energies of the interacting objects with their masses.  The key is to always remember that we are talking about INTERACTIONS.  The mass lost by Object A appears as the kinetic energy of Object B, and vice-versa.
Quote from: Farsight on 08/08/2009 08:45:44
With the falling plate example we use the planet as our reference frame and we say that mass of the plate is so small that the planet's motion is not detectable. The plate's motion however is detectable. It's 11km/s. Once it's on the ground having lost its kinetic energy, the gravitational time dilation means everything moving in that plate, be it molecules or atoms or electrons or light, is moving slower than it was. That's where the energy came from. 
Certainly the energy that emanates from the collided bodies came from the kinetic energies of the bodies.  But we are talking about where the kinetic energy came from: mass.



To Raghavendra:
If we assume a constant vibration rate --a kind of velocity-- for the molecules of some resting mass, at various locations in a gravitational field gradient, then:
1. General Relativity is a well-verified theory; the longer lengths and the slower time associated with the depths of a gravity gradient are widely accepted by physicists.
2. Quantum Mechanics and the wave/particle duality are also well-verified; the association of momentum (and thus mass if velocity is constant) with length and frequency is also widely accepted.
3. Therefore a mass' magnitude must change with its resting place (still assuming constant molecular vibrations) in a gravity gradient, just as does its gravitational potential energy!
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Offline Farsight

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If I give an object some potential energy, does its mass increase?
« Reply #42 on: 10/08/2009 19:02:09 »
Quote from: Pmb
That was merely his first paper on the subject of mass, not his last. Over the years he refined the subject and developed relations for more and more general cases. It appears to me that you mistook his first word on the subject for his final word. For example see The Principle of Conservation of the Center of Gravity and the Inertia of Energy, Albert Einstein, Annalen der Physik, 20 (1906): 626-633. In this paper Einstein assigns a mass density to radiation. In still later work he developes an expression for the inertia of stress and finally states that mass is completely defined by the energy-momentum tensor. With that tensor one can prove all the properties that physicists attribute to mass, such as the fact that the inertial mass density of a gas is a function of pressure.
No problem. The point is that I wasn't just making up that definition. The mass of the plate is a measure of its energy content. And the dimensionality of energy is stress x volume.

Quote from: Raghavendra on 09/08/2009 09:21:07
No. You can't increase the mass of a plate.
Take a planet sitting motionless in space. Take a plate, motionless on that planet. Fire that plate at 11km/s and give it enough kinetic energy to achieve escape velocity. Examine the plate later when it is motionless in space with respect to the planet. You gave it more energy. You gave it more mass.

Quote from: VernonNemitz on 10/08/2009 15:02:40
Do not confuse the kinetic energies of the interacting objects with their masses. The key is to always remember that we are talking about INTERACTIONS. The mass lost by Object A appears as the kinetic energy of Object B, and vice-versa.
Sorry Vernon, we've got a plate in a gravitational field. There's is no magical mysterious action-at-a-distance between the plate and the earth. The earth doesn't lose mass because the plate is falling. There isn't time for the earth/plate interaction to occur. And the earth's gravitational field doesn't lose mass either. The energy in the surrounding region of space, where the gravitational field is, increases.

Quote from: VernonNemitz on 10/08/2009 15:02:40
Certainly the energy that emanates from the collided bodies came from the kinetic energies of the bodies. But we are talking about where the kinetic energy came from: mass.
We agree that the kinetic energy comes from the mass. I'd hope your reply to Raghavendra might make you appreciate that you can take this a stage further to agree on which mass it comes from.

Let me outline why things fall down, because I think you'll find it useful:

Many people think of gravity as "curved spacetime", and think this is the cause of gravity. It isn't. There's a further issue in that people see the bowling-ball-rubber-sheet analogy, and think the curvature here is the curved spacetime. It isn't. This is depicting the way gravity reduces in line with the inverse square law:   


(Artwork copyright Boris Starosta 2005)

Take a sample square from the picture above and zoom into it to give yourself a smaller square. Keep zooming in until you can't see any of that original curvature. The square you're looking at represents space, and whilst it exhibits no curvature, it isn't flat because it exhibits a gradient:
 


There is a gradient in the local properties of space that you can detect in a room when you drop a pencil or throw a ball. Roll a marble across the square and track its path over time. This path is curved. That's curved spacetime. It isn't the cause of gravity, the gradient is the cause. The curved spacetime is the effect.

Here's the analogy: You have a toy motor boat. You set it going up a boating lake, and it goes straight as a die. Its path doesn't curve. Now we repeat the experiment, only this time I've shovelled a truckful of powdered wallpaper paste all down the left hand side of the lake. We wait overnight, and in the morning we find we've got a viscosity gradient from left to right across the lake. This is an analogy for the energy density gradient in the space surrounding the planet. We set the toy motorboat going up the lake. This time it doesn't travel in a straight line, it curves to the left. This toy motorboat equates to a passing photon which is deflected by the gravitational field.

Now we retrieve our boat, and jam its rudder over to the left. We set it down on the lake with the motor running, and it travels round and round in a tight circle. But every time it's going up the lake, it veers over to the left ever so slightly. It also does this when it's coming round the other way. As a result, it gradually works its way over to the left. This toy motorboat equates to an electron falling straight down in a gravitational field. (I'll have to tell you more about pair production to explain why, but please take it as read for now). Note that the circling boat is travelling up or down the lake for only half of each cycle. For the other half it's travelling left and right. You can simplify the circle to a square to appreciate this. This is why matter is deflected half as much as light.   

Finally, observe the boat when its has worked its way over to the left hand side of the lake. It's still going round in circles, but at a slower rate than it did, because of the increased viscosity. The reduced cycle rate is related to the rate of travel to the left. The cycling motion is being converted into lateral motion.

Think of your plate as a whole flotilla of boats. The reduced cycle rate represents reduced energy within the plate. The travel to the left represents the kinetic energy. If you discard the latter, you're left with a reduced mass in your plate. It's really simple once it clicks. There's nothing mysterious about it, and no negative mass or energy.
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #43 on: 11/08/2009 15:20:58 »
Quote from: Farsight on 10/08/2009 19:02:09
Quote from: VernonNemitz on 10/08/2009 15:02:40
Do not confuse the kinetic energies of the interacting objects with their masses. The key is to always remember that we are talking about INTERACTIONS. The mass lost by Object A appears as the kinetic energy of Object B, and vice-versa.
Sorry Vernon, we've got a plate in a gravitational field. There's is no magical mysterious action-at-a-distance between the plate and the earth. The earth doesn't lose mass because the plate is falling. There isn't time for the earth/plate interaction to occur. And the earth's gravitational field doesn't lose mass either. The energy in the surrounding region of space, where the gravitational field is, increases.

Quote from: VernonNemitz on 10/08/2009 15:02:40
Certainly the energy that emanates from the collided bodies came from the kinetic energies of the bodies. But we are talking about where the kinetic energy came from: mass.
We agree that the kinetic energy comes from the mass. I'd hope your reply to Raghavendra might make you appreciate that you can take this a stage further to agree on which mass it comes from.
I will continue to disagree with you, because at the end of YOUR scenario the two masses no longer have the same mass ratio they started with, which violates General Relativity's allowing of easy reference-frame-switching (in which masses don't change at all).  You have offered nothing at all to deal with that very significant problem!

Furthermore, GR isn't the Last Word on gravitation; Quantum Mechanics is going to eventually have a very significant "say" on the subject (has already had some; look up "Hawking Radiation"), and indeed there will be interactions, and time for interactions, when that "say" arrives in detail.  My argument that the mass lost by A appears as the kinetic energy of B, is based on the inevitability that QM will have its "say".
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Offline Pmb

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If I give an object some potential energy, does its mass increase?
« Reply #44 on: 12/08/2009 16:30:07 »
Quote from: Raghavendra on 09/08/2009 09:21:07
No.. You can't increase the mass of a plate.
Responses like this are rarely helpful since they convey no understanding. It's already been agreed that (1) the proper mass does not change and (2) the relativistic mass does. Simply saying You can't increase the mass of a plate adds nothing to the conversation.
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Offline Pmb

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If I give an object some potential energy, does its mass increase?
« Reply #45 on: 12/08/2009 17:08:41 »
Quote from: Farsight
The mass of the plate is a measure of its energy content. And the dimensionality of energy is stress x volume.
There is very serious/major flaw in that kind of logic, one which I addressed in the article I wrote which is located at http://arxiv.org/abs/0709.0687

In short, just because you can give something units of energy it doesn't mean that it really is the energy of something. For example; I can ,multiply any constant which has the units of energy by v^2/c^2 and add it to the real energy. The results have the units of energy but is a meaningless quantity.
« Last Edit: 12/08/2009 17:18:40 by Pmb »
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #46 on: 12/08/2009 18:52:53 »
Quote from: Pmb on 12/08/2009 17:08:41
...the article I wrote which is located at http://arxiv.org/abs/0709.0687

That looks like a reasonably nice article.  I saw a couple of typos, but no big deal.  And you left out my own personal sneaking-suspicion-definition of mass:  "All mass is potential-energy-stored-as-mass."  Heh!
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Offline Farsight

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If I give an object some potential energy, does its mass increase?
« Reply #47 on: 18/08/2009 12:00:42 »
Sorry everybody, I've had a big weekend and have been out of action.

Quote from: VernonNemitz on 11/08/2009 15:20:58
I will continue to disagree with you, because at the end of YOUR scenario the two masses no longer have the same mass ratio they started with, which violates General Relativity's allowing of easy reference-frame-switching (in which masses don't change at all).  You have offered nothing at all to deal with that very significant problem!
I've offered plenty, Vernon. The bottom line is that with the falling plate scenario, the earth has no detectable motion, whilst the plate does. 11km/s is darn pretty detectable. 

Quote from: VernonNemitz on 11/08/2009 15:20:58
Furthermore, GR isn't the Last Word on gravitation; Quantum Mechanics is going to eventually have a very significant "say" on the subject..
OK, maybe GR as we understand it now isn't quite the last word on gravitation, but I'm afraid quantum mechanics isn't going to have a significant say on the subject. You can't quantize gravity.

Quote from: VernonNemitz on 11/08/2009 15:20:58
(has already had some; look up "Hawking Radiation")
I'm afraid Hawking Radiation is hypothesis, not a fact.

Quote from: VernonNemitz on 11/08/2009 15:20:58
..and indeed there will be interactions, and time for interactions, when that "say" arrives in detail.  My argument that the mass lost by A appears as the kinetic energy of B, is based on the inevitability that QM will have its "say".
With respect Vernon, you're clutching at straws with this. Stick to the observables and the logic.
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Offline Farsight

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If I give an object some potential energy, does its mass increase?
« Reply #48 on: 18/08/2009 12:46:58 »
Quote from: Pmb on 12/08/2009 17:08:41
Quote from: Farsight
The mass of the plate is a measure of its energy content. And the dimensionality of energy is stress x volume.
There is very serious/major flaw in that kind of logic, one which I addressed in the article I wrote which is located at http://arxiv.org/abs/0709.0687
I've re-read your article Pete. Here's part of your conclusion below:

Conclusion
I have demonstrated above that there are omissions, specious arguments
and errors on both sides of the relativistic mass/proper mass debate that has left
some areas in this dispute empty. I have also demonstrated that the claim that
relativistic mass can be replaced by inertial energy is wrong in general. I gave
one example and showed how such thinking could lead to an apparent paradox.
I have also shown that the quantity which deserves the name mass more than
anything else is relativistic mass since it is that quantity which possesses all three
aspects of mass, i.e. inertial mass, passive gravitational mass and active
gravitational mass. Accusations that relativistic mass is confusing cannot serve as
a strike against relativistic mass since almost all aspects of relativity are
confusing until they are mastered and once mastered they’re not confusing at all...


I agree with your argument, but there's no flaw in what I said. Just a simplification, and a bending to convention. Look at pair production. A photon has energy E=hf and momentum p=hf/c, but it really has energy/momentum and there's a distance-based and a time-based measure. A photon is converted into an electron and a positron. The electron has spin and angular momentum. See http://en.wikipedia.org/wiki/Planck_constant for "The Planck constant has dimensions of energy multiplied by time, which are also the dimensions of action. In SI units, the Planck constant is expressed in joule seconds (J s). The dimensions may also be written as momentum multiplied by distance (N m s), which are also the dimensions of angular momentum". In simple terms the electron is a photon travelling in a circular path, so the photon is "going nowhere fast". Hence momentum now appears as inertia. If it’s side-on and moving relative to you, you'd see this circular path looking like a helical path. One full turn round the helix represents the relativistic mass, the total energy. The circular component of this represents the "rest" mass. The difference represents the kinetic energy. It tells you how fast the energy that's going nowhere fast, is going somewhere.

Quote from: Pmb on 12/08/2009 17:08:41
In short, just because you can give something units of energy it doesn't mean that it really is the energy of something. For example; I can multiply any constant which has the units of energy by v^2/c^2 and add it to the real energy. The results have the units of energy but is a meaningless quantity.
Quite so. What's the energy of a photon? What you measure depends on your relative motion. Move towards it fast, and it's blue-shifted, so it appears to have a higher energy. But when you move towards that photon it doesn't acquire any extra energy at all. It didn't change, you did. It's the same for the blue-shifted photon in the Pound-Rebka experiment. It has not gained any extra energy. And it's the same for the falling plate. The total energy of the falling plate at the surface is the same as that of the plate at rest at altitude.   
« Last Edit: 18/08/2009 12:48:44 by Farsight »
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #49 on: 18/08/2009 16:45:57 »
To Farsight:

Just because you SAY you have offered an explanation about how, before a plate falls and afterward, the mass ratios of it-to-planet don't change, that doesn't mean you have actually done any such thing.  Therefore, until I observe such an explanation, I will continue to say that your description violates General Relativity's freedom to switch reference frames (your description of where the kinetic energy comes from).  Also, I forgot to say previously that there is one other problem with a falling object sacrificing its own mass to become its kinetic energy:  It would make black holes unlikely (they would be an asymptotic limit of a curve-of-accumulation of ever-smaller arriving masses!).

Next, just because you SAY that gravity can't be quantized, that doesn't mean you are right, not at all!  Certainly you can't prove such a silly claim, and lots of people have made stabs at concocting something sensible.  String theory, for example.  Sure, not useful for much, since it hasn't made any testable predictions.  But even I can devise a reasonable QM description of gravity: http://knol.google.com/k/vernon-nemitz/simple-quantum-gravitation/131braj0vi27a/2
Part of it can even be tested: http://www.halfbakery.com/idea/Gravity_20Waves2#1225479012

Regarding Hawking Radiation, there is some evidence that you are quite wrong there.  Remember all the fuss about potential black hole formation at large particle accelerator facilities?  The fuss has been around since well before the Large Hadron Collider was constructed, see: http://en.wikipedia.org/wiki/Relativistic_Heavy_Ion_Collider
The main argument for the safety of the accelerators involves natural cosmic rays, which can be vastly more energetic than we can currently dream about making (to say nothing of actually making).  In 4 billion years of getting zapped by them, either no black hole was ever created by any of those events, able to devour the Earth, or Hawking Radiation has been there to save the world.  The likelier explanation is Hawking Radiation.  ALSO, there have been "events" at the RHIC which may be interpreted as quantum-black-hole explosions (which again are only possible per Hawking Radiation): http://news.bbc.co.uk/2/hi/science/nature/4357613.st
And there is one other category of mystery event, something called a "Bosenova", which can occur in a Bose-Einstein Condensate:  http://www.npl.washington.edu/av/altvw108.html   I'm speculating, of course, but it shouldn't take much thought to see the possibility of many atoms in a BEC, able to exist at a single point, being equivalent to the singularity in a black hole.  So, why doesn't such a black hole form, and the atoms stay trapped inside?  How about Hawking Radiation (or an equivalent)?

Finally, I remind you of Aristotle, who was quite right about a number of things, and as a result led people to think that Authority, logic, and a MINIMUM number of observables was all that was needed to reach a valid conclusion.  But Aristotle was dead wrong about objects in motion, which was why Isaac Newton had to explictly specify his First Law of Motion, even though it is "built into" the Second Law.  Newton had to overthrow Aristotlean/Authoritarian nonsense.  And that means YOUR mere say-so isn't good enough, either.
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Offline Farsight

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If I give an object some potential energy, does its mass increase?
« Reply #50 on: 18/08/2009 19:10:12 »
Quote from: VernonNemitz on 18/08/2009 16:45:57
Just because you SAY you have offered an explanation about how, before a plate falls and afterward, the mass ratios of it-to-planet don't change, that doesn't mean you have actually done any such thing.  Therefore, until I observe such an explanation, I will continue to say that your description violates General Relativity's freedom to switch reference frames (your description of where the kinetic energy comes from). Also, I forgot to say previously that there is one other problem with a falling object sacrificing its own mass to become its kinetic energy: It would make black holes unlikely (they would be an asymptotic limit of a curve-of-accumulation of ever-smaller arriving masses!).
It doesn't make black holes unlikely. Look at it this way. Imagine you've got a large region of space with a black hole in it. Now introduce a billion-tonne asteriod and let it go. It falls and falls and falls towards the black hole, accelerating all the time. It's going really fast when it gets swallowed up by the black hole. Then the mass/energy of the black hole is increased. But it's only increased by the energy-equivalent of a billion tonnes, not by any more than that.

Quote from: VernonNemitz on 18/08/2009 16:45:57
Next, just because you SAY that gravity can't be quantized, that doesn't mean you are right, not at all! Certainly you can't prove such a silly claim, and lots of people have made stabs at concocting something sensible. String theory, for example. Sure, not useful for much, since it hasn't made any testable predictions. But even I can devise a reasonable QM description of gravity: http://knol.google.com/k/vernon-nemitz/simple-quantum-gravitation/131braj0vi27a/2
Part of it can even be tested: http://www.halfbakery.com/idea/Gravity_20Waves2#1225479012
It really isn't a silly claim, Vernon. A photon exhibits energy, so it has an active gravitational mass. And when a photon approaches you it does so smoothly. That means the gravity increases smoothly. Thinking you can quantize gravity is the silly claim (though I didn't say that to Lee Smolin).

When I looked at your link I got Knol is currently unavailable and is undergoing maintenance. I have no issue with gravity waves. One can think of them as akin to a "supersize" photon.

Quote from: VernonNemitz on 18/08/2009 16:45:57
Regarding Hawking Radiation, there is some evidence that you are quite wrong there. Remember all the fuss about potential black hole formation at large particle accelerator facilities?  The fuss has been around since well before the Large Hadron Collider was constructed, see: http://en.wikipedia.org/wiki/Relativistic_Heavy_Ion_Collider
The main argument for the safety of the accelerators involves natural cosmic rays, which can be vastly more energetic than we can currently dream about making (to say nothing of actually making). In 4 billion years of getting zapped by them, either no black hole was ever created by any of those events, able to devour the Earth, or Hawking Radiation has been there to save the world. The likelier explanation is Hawking Radiation. ALSO, there have been "events" at the RHIC which may be interpreted as quantum-black-hole explosions (which again are only possible per Hawking Radiation): http://news.bbc.co.uk/2/hi/science/nature/4357613.st
I get a 404 page not found when I follow that link. I know about RHIC and all this stuff. Hawking radiation isn't the "likelier" explanation, and the fact remains that nobody has seen any Hawking radiation. There's absolutely no evidence for it. It remains conjecture. A hypothesis.    

Quote from: VernonNemitz on 18/08/2009 16:45:57
And there is one other category of mystery event, something called a "Bosenova", which can occur in a Bose-Einstein Condensate:  http://www.npl.washington.edu/av/altvw108.html 
I know this stuff like the back of my hand:

"In the 1920s, therefore, it came as a big surprise when experimental physicists discovered that the electron breaks this quantum rule by having a spin angular momentum that is ½ of an h/2p unit (i.e., spin ½).  This means that electrons (along with quarks, neutrinos, protons, neutrons, and many atoms) are NOT the same after a 360o rotation.  They must be rotated through two full turns or 720o before they return to their original states.  This peculiar spin behavior is not well understood, but it is nevertheless an accepted fact of quantum physics".

This is a depiction of the electron:



Follow the dark black line round and note the 720o degrees of rotation to get back to the original orientation and position. However the Bosenova is very interesting. You might have drawn my attention to something important there. Thanks.

Quote from: VernonNemitz on 18/08/2009 16:45:57
I'm speculating, of course, but it shouldn't take much thought to see the possibility of many atoms in a BEC, able to exist at a single point, being equivalent to the singularity in a black hole. So, why doesn't such a black hole form, and the atoms stay trapped inside?  How about Hawking Radiation (or an equivalent)?
There is no singularity "in" a black hole. The singularity is at the event horizon. But we're getting off the point with this. There's no evidence for Hawking Radiation. It remains a speculation. The 11 kms of the falling plate is not a speculation, and nor is conservation of energy.   

Quote from: VernonNemitz on 18/08/2009 16:45:57
Finally, I remind you of Aristotle, who was quite right about a number of things, and as a result led people to think that Authority, logic, and a MINIMUM number of observables was all that was needed to reach a valid conclusion. But Aristotle was dead wrong about objects in motion, which was why Isaac Newton had to explictly specify his First Law of Motion, even though it is "built into" the Second Law. Newton had to overthrow Aristotlean/Authoritarian nonsense. And that means YOUR mere say-so isn't good enough, either.
I don't mean to give a mere say so, I mean to give evidence and careful logic and a rational argument. Sometimes I might not give enough. I admit I haven't given enough re the quantization of gravity, but we can always talk about it further. 
« Last Edit: 18/08/2009 19:14:24 by Farsight »
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #51 on: 18/08/2009 20:26:01 »
Quote from: Farsight on 18/08/2009 19:10:12
Quote from: VernonNemitz on 18/08/2009 16:45:57
I forgot to say previously that there is one other problem with a falling object sacrificing its own mass to become its kinetic energy: It would make black holes unlikely (they would be an asymptotic limit of a curve-of-accumulation of ever-smaller arriving masses!).
It doesn't make black holes unlikely. Look at it this way. Imagine you've got a large region of space with a black hole in it. Now introduce a billion-tonne asteriod and let it go. It falls and falls and falls towards the black hole, accelerating all the time. It's going really fast when it gets swallowed up by the black hole. Then the mass/energy of the black hole is increased. But it's only increased by the energy-equivalent of a billion tonnes, not by any more than that.
You are mistaking what I was talking about; you are assuming an already-existing black hole.  But try adding mass to a neutron star, and you will see what I mean; if there is time for the kinetic energy after impact to radiate away, then the neutron star will have difficulty becoming a black hole, no matter how much mass falls toward it.  (Note I did originally say "unlikely", not "impossible".) 

Quote from: Farsight on 18/08/2009 19:10:12
Quote from: VernonNemitz on 18/08/2009 16:45:57
... even I can devise a reasonable QM description of gravity: http://knol.google.com/k/vernon-nemitz/simple-quantum-gravitation/131braj0vi27a/2
Part of it can even be tested: http://www.halfbakery.com/idea/Gravity_20Waves2#1225479012
It really isn't a silly claim, Vernon. A photon exhibits energy, so it has an active gravitational mass. And when a photon approaches you it does so smoothly. That means the gravity increases smoothly. Thinking you can quantize gravity is the silly claim (though I didn't say that to Lee Smolin).
When I looked at your link I got Knol is currently unavailable and is undergoing maintenance.
Hmmm...the link worked just fine a few minutes ago when I tried it, just before writing this.
Yours is still a silly claim, since you are making it in apparent ignorance of how quantized gravitation MIGHT work.  For example a photon of ordinary light has multi-terahertz frequency; how do you know it is not interacting gravitationally at a similar rate?  The "fine-ness" of Planck's Constant is plenty to allow photon-motion to be smoothly curved in a gravitational field, just as it has been plenty to make other things look smooth at our macroscopic scale.

Quote from: Farsight on 18/08/2009 19:10:12
Quote from: VernonNemitz on 18/08/2009 16:45:57
Regarding Hawking Radiation, there is some evidence that you are quite wrong there. Remember all the fuss about potential black hole formation at large particle accelerator facilities?  The fuss has been around since well before the Large Hadron Collider was constructed, see: http://en.wikipedia.org/wiki/Relativistic_Heavy_Ion_Collider
The main argument for the safety of the accelerators involves natural cosmic rays, which can be vastly more energetic than we can currently dream about making (to say nothing of actually making). In 4 billion years of getting zapped by them, either no black hole was ever created by any of those events, able to devour the Earth, or Hawking Radiation has been there to save the world. The likelier explanation is Hawking Radiation. ALSO, there have been "events" at the RHIC which may be interpreted as quantum-black-hole explosions (which again are only possible per Hawking Radiation): http://news.bbc.co.uk/2/hi/science/nature/4357613.st
I get a 404 page not found when I follow that link. I know about RHIC and all this stuff. Hawking radiation isn't the "likelier" explanation, and the fact remains that nobody has seen any Hawking radiation. There's absolutely no evidence for it. It remains conjecture. A hypothesis.
I said, in effect, The Evidence Is That Planet Earth Is Still Here, after 4 billion years of most-extreme-energy cosmic-ray collisions.  Are you claiming that quantum black holes are impossible, or that none can ever be produced by such a collision?  What IS your explanation for that Evidence?
Regarding the link, sorry, a typo crept into it during my previous editing.  Here:  http://news.bbc.co.uk/2/hi/science/nature/4357613.stm  We are talking about actual data here, that MAY match the theoretical description of Hawking Radiation. 

Quote from: Farsight on 18/08/2009 19:10:12
There is no singularity "in" a black hole. The singularity is at the event horizon.
  Now you are dead wrong.  Look up the so-called "Law of Cosmic Censorship".  The singularity is the mathematical point at the center of a black hole, toward which everything inside the event horizon is endlessly falling.  Note per YOUR claim that an object's mass diminishes as it falls/accelerates, its mass can fall to zero as it reaches the event horizon, and therefore it can reach light-speed and enter the body of the black hole.  There is no big pile-up of time-slowed stuff outside the event horizon, waiting to get in.  (And in any scenario that includes Hawking Radiation, there also will be quantum fluctuations of the event horizon such that anything having >0 mass just outside the event horizon can still be swallowed.  One moment it is outside; fluctuation; now it is inside, still falling and so unable to get out again.)

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Offline Farsight

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If I give an object some potential energy, does its mass increase?
« Reply #52 on: 19/08/2009 17:15:59 »
Quote from: VernonNemitz on 18/08/2009 16:45:57
You are mistaking what I was talking about; you are assuming an already-existing black hole.  But try adding mass to a neutron star, and you will see what I mean; if there is time for the kinetic energy after impact to radiate away, then the neutron star will have difficulty becoming a black hole, no matter how much mass falls toward it. (Note I did originally say "unlikely", not "impossible".)
OK, agreed. It ties in with what I was saying about the black hole.  

Quote from: VernonNemitz on 18/08/2009 16:45:57
Hmmm...the link worked just fine a few minutes ago when I tried it, just before writing this. Yours is still a silly claim, since you are making it in apparent ignorance of how quantized gravitation MIGHT work. For example a photon of ordinary light has multi-terahertz frequency; how do you know it is not interacting gravitationally at a similar rate? The "fine-ness" of Planck's Constant is plenty to allow photon-motion to be smoothly curved in a gravitational field, just as it has been plenty to make other things look smooth at our macroscopic scale.
Just take it from me that I know how this works. It might seem like a silly claim to you, but I promise you it isn't. I'll send you something to back this up. 

Quote from: VernonNemitz on 18/08/2009 16:45:57
I said, in effect, The Evidence Is That Planet Earth Is Still Here, after 4 billion years of most-extreme-energy cosmic-ray collisions.  Are you claiming that quantum black holes are impossible, or that none can ever be produced by such a collision?  What IS your explanation for that Evidence? Regarding the link, sorry, a typo crept into it during my previous editing.  Here:  http://news.bbc.co.uk/2/hi/science/nature/4357613.stm. We are talking about actual data here, that MAY match the theoretical description of Hawking Radiation.
Yes, I'm saying quantum black holes are impossible. None will be produced by such a collision, because the required extra dimensions do not exist. I followed your link then looked at the paper at arXiv. IMHO it's clutching at straws.   

Quote from: VernonNemitz on 18/08/2009 16:45:57
Now you are dead wrong. Look up the so-called "Law of Cosmic Censorship". The singularity is the mathematical point at the center of a black hole, toward which everything inside the event horizon is endlessly falling. Note per YOUR claim that an object's mass diminishes as it falls/accelerates, its mass can fall to zero as it reaches the event horizon, and therefore it can reach light-speed and enter the body of the black hole. There is no big pile-up of time-slowed stuff outside the event horizon, waiting to get in.
I'm dead right about this, Vernon. And the law of cosmic censorship is just another hypothesis. 

Quote from: VernonNemitz on 18/08/2009 16:45:57
And in any scenario that includes Hawking Radiation, there also will be quantum fluctuations of the event horizon such that anything having >0 mass just outside the event horizon can still be swallowed. One moment it is outside; fluctuation; now it is inside, still falling and so unable to get out again.
Isn't it supposed to be the other way round, in that a fluctuation leaves a particle outside the event horizon whereupon it escapes as Hawking radiation, stealing mass/energy from the black hole. Besides, Hawking radiation isn't really relevant. We were talking about potential energy and a plate. When you raise the plate you give the plate that potential energy. When it falls, that potential energy is converted into kinetic energy. The kinetic energy comes from the plate. It's really simple. What you've been taught would leave you with an asteroid falling into a black hole and giving it more mass/energy than the asteroid had to begin with. That breaks the rules of conservation of energy.     

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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #53 on: 19/08/2009 18:41:01 »
Quote from: Farsight on 19/08/2009 17:15:59
Quote from: VernonNemitz on 18/08/2009 16:45:57
Hmmm...the link worked just fine a few minutes ago when I tried it, just before writing this. Yours is still a silly claim, since you are making it in apparent ignorance of how quantized gravitation MIGHT work. For example a photon of ordinary light has multi-terahertz frequency; how do you know it is not interacting gravitationally at a similar rate? The "fine-ness" of Planck's Constant is plenty to allow photon-motion to be smoothly curved in a gravitational field, just as it has been plenty to make other things look smooth at our macroscopic scale.
Just take it from me that I know how this works. It might seem like a silly claim to you, but I promise you it isn't. I'll send you something to back this up. 
You should post it for all to see, if possible.  You also still need to post something I mentioned a while back: an explanation for how the mass ratio of plate-to-planet does not change, as required to be consistent with General Relativity's allowing of reference-frame-swapping, when you want the kinetic energy of the plate to appear at the expense of the mass of the plate only, when it falls toward the planet.

Quote from: Farsight on 19/08/2009 17:15:59
Yes, I'm saying quantum black holes are impossible. None will be produced by such a collision, because the required extra dimensions do not exist.
I'm not aware that extra dimensions are required for quantum-sized black holes to exist.  Black holes of any size strictly depend on the amount of mass crammed into a given volume, and nothing more than that, to the best of my knowledge.  So, again you appear to be making an arbitrary Authoritarian statement, without backing it up.

Quote from: Farsight on 19/08/2009 17:15:59
... the law of cosmic censorship is just another hypothesis. 
True, but the DEFINITION of that hypothesis specifies a distinction between a singularity (more specifically, a "naked singularity") and an event horizon, which is why you are dead wrong in saying they are the same thing; physicists had specified the distinction between the two things well before the "censorship law" was proposed.

Quote from: Farsight on 19/08/2009 17:15:59
Quote from: VernonNemitz on 18/08/2009 16:45:57
And in any scenario that includes Hawking Radiation, there also will be quantum fluctuations of the event horizon such that anything having >0 mass just outside the event horizon can still be swallowed. One moment it is outside; fluctuation; now it is inside, still falling and so unable to get out again.
Isn't it supposed to be the other way round, in that a fluctuation leaves a particle outside the event horizon whereupon it escapes as Hawking radiation, stealing mass/energy from the black hole.
Hawking radiation is also about "virtual particles in the vacuum", not just event-horizon fluctuations.  The event horizon fluctuates to swallow one of a pair of virtual particles; the other becomes real and MIGHT escape the hole.  But I was not talking about virtual particles at all; I was talking about already-real particles that had closely approached the event horizon by falling toward the hole.  Anyone who thinks that gravitational time dilation and/or other effects will prevent the real particles from entering the hole is failing to take those same event-horizon-fluctuations into account.


Quote from: Farsight on 19/08/2009 17:15:59
Besides, Hawking radiation isn't really relevant. We were talking about potential energy and a plate. When you raise the plate you give the plate that potential energy. When it falls, that potential energy is converted into kinetic energy. The kinetic energy comes from the plate. It's really simple. What you've been taught would leave you with an asteroid falling into a black hole and giving it more mass/energy than the asteroid had to begin with. That breaks the rules of conservation of energy.
Start over, and be more specific:  When you raise the plate (to, say, a shelf) you put potential energy into the plate/planet SYSTEM.  We are agreed that the mass of the system must increase, to match the increased potential energy.  We are disagreeing about details of where the increased mass goes.  You say it goes into the plate; I say most of it goes into the planet.  When the plate falls off the shelf and acquires kinetic energy at the expense of potential-energy-stored-as-mass, NEITHER of us has a problem with the Law of Energy Conservation.  (And no, if the black hole loses mass that appears as the kinetic energy of the asteroid, it simply gets that mass back after swallowing the asteroid; no net increase happens, of the hole/asteroid system.  Also, in terms of Quantum Mechanics, there are two possible answers to the question "How do gravitons get out of a black hole?"  Do you know either of those answers?)

Regardless of the preceding, YOU still have a problem with General Relativity that I don't have; your scenario means the mass-ratio of plate-to-planet must change, in violation of the rules that allow reference-frame-swapping.  (By the way, I might mention that I held your opinion a number of years ago, and had to abandon it for the same reason I'm giving you now.  Some of that is described in the essay I mentioned much earlier in this Thread, http://www.nemitz.net/vernon/STUBBED2.pdf --it would be nice to get some feedback about that, thanks!)
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If I give an object some potential energy, does its mass increase?
« Reply #54 on: 20/08/2009 00:02:39 »
Quote from: Farsight
I know this stuff like the back of my hand:..
We've all heard that statement a lot over the years since it makes a nice analogy when we're talking about something that we know very well. use that saying alot. Being a physicist I'm quite curious by nature so I trued a little experiment one day. I sat on my hands and tried to remember the number of moles or marks that are on the back of my hands. It then occurred to me that I had a poor recollection of what the back of my hands look like. ROTFL!!!
Quote from: Farsight
There is no singularity "in" a black hole. The singularity is at the event horizon.
Can you explain this response to me in mode detail? It is not inconceivable that the mass distribution inside, say, a primordial black hole could have all its matter at the center of the black hole. It would be impossible for an outside observer to make this determination.
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Offline Farsight

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If I give an object some potential energy, does its mass increase?
« Reply #55 on: 21/08/2009 13:48:03 »
Quote from: VernonNemitz on 19/08/2009 18:41:01
You should post it for all to see, if possible.
It's too bulky, Vernon.

Quote from: VernonNemitz on 19/08/2009 18:41:01
You also still need to post something I mentioned a while back: an explanation for how the mass ratio of plate-to-planet does not change, as required to be consistent with General Relativity's allowing of reference-frame-swapping, when you want the kinetic energy of the plate to appear at the expense of the mass of the plate only, when it falls toward the planet.
But it does change. However if you follow the plate down to the surface, everything that happens to the plate also happens to you, you rods and clocks, and all other measuring devices. For example if you use a spring-powered pushing devices to assess the mass of the plate, that loses energy too. So you won't measure a reduction in the mass of the plate. It's an "immersive scale change". Your reference frame has changed, along with everything in it, including you. You don't notice the changes locally, you only notice them when you do a comparison with afar and notice the gravitational time dilation. In your new reference frame everything is moving slower, but so are you and your clocks, so you don't notice it locally. 

Quote from: VernonNemitz on 19/08/2009 18:41:01
I'm not aware that extra dimensions are required for quantum-sized black holes to exist. Black holes of any size strictly depend on the amount of mass crammed into a given volume, and nothing more than that, to the best of my knowledge.  So, again you appear to be making an arbitrary Authoritarian statement, without backing it up.
I'm not. See http://en.wikipedia.org/wiki/Micro_black_hole where it says "In familiar three-dimensional gravity, the minimum energy of a microscopic black hole is 1019 GeV, which would have to be condensed into a region of approximate size 10-33 cm. This is far beyond the limits of any current technology. "

Quote from: VernonNemitz on 19/08/2009 18:41:01
Quote from: Farsight on 19/08/2009 17:15:59
... the law of cosmic censorship is just another hypothesis. 
True, but the DEFINITION of that hypothesis specifies a distinction between a singularity (more specifically, a "naked singularity") and an event horizon, which is why you are dead wrong in saying they are the same thing; physicists had specified the distinction between the two things well before the "censorship law" was proposed.
The event horison isn't the same thing as the "naked" singularity associated with cosmic censorship. It isn't a point, it's a surface.

Quote from: VernonNemitz on 19/08/2009 18:41:01
Hawking radiation is also about "virtual particles in the vacuum", not just event-horizon fluctuations.  The event horizon fluctuates to swallow one of a pair of virtual particles; the other becomes real and MIGHT escape the hole.
If you talk about that, talk about the situation where it swallows both virtual particles. Then the black hole is eating the vacuum energy of space. And it grows. 

Quote from: VernonNemitz on 19/08/2009 18:41:01
But I was not talking about virtual particles at all; I was talking about already-real particles that had closely approached the event horizon by falling toward the hole.  Anyone who thinks that gravitational time dilation and/or other effects will prevent the real particles from entering the hole is failing to take those same event-horizon-fluctuations into account.
It's just more hypothesis, Vernon. The gravitational time dilation at the event horizon is total. The time dilation is infinite. Try fluctuating infinity. 

Quote from: VernonNemitz on 19/08/2009 18:41:01
Start over, and be more specific:  When you raise the plate (to, say, a shelf) you put potential energy into the plate/planet SYSTEM.
No, you don't. You're in that system. The total energy of the system hasn't changed. If it had, this system would exert more gravity than previously. It doesn't.

Quote from: VernonNemitz on 19/08/2009 18:41:01
We are agreed that the mass of the system must increase, to match the increased potential energy.
OK, if I reached down into the system to lift that plate up on to the shelf, I've given the plate potential energy and I've increased the total energy of the plate/planet system.

Quote from: VernonNemitz on 19/08/2009 18:41:01
We are disagreeing about details of where the increased mass goes.  You say it goes into the plate; I say most of it goes into the planet.  When the plate falls off the shelf and acquires kinetic energy at the expense of potential-energy-stored-as-mass, NEITHER of us has a problem with the Law of Energy Conservation.
Fair enough.

Quote from: VernonNemitz on 19/08/2009 18:41:01
And no, if the black hole loses mass that appears as the kinetic energy of the asteroid...
That would require action-at-a-distance. You've got mass magically leaping across a million miles of space to appear as the kinetic energy of the asteroid? No, it can't be like that. And the space surrounding the black hole doesn't lose any mass either, for the same reason. There's only one place left, Vernon.

Quote from: VernonNemitz on 19/08/2009 18:41:01
..it simply gets that mass back after swallowing the asteroid; no net increase happens, of the hole/asteroid system.
I agree that there's no net increase.   

Quote from: VernonNemitz on 19/08/2009 18:41:01
Also, in terms of Quantum Mechanics, there are two possible answers to the question "How do gravitons get out of a black hole?"  Do you know either of those answers?)
Yes, here's one re virtual gravitons that go faster than light and break the laws of physics. http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980601a.html. Note that gravitons aren't part of the standard model. Again they're hypothetical.

Quote from: VernonNemitz on 19/08/2009 18:41:01
Regardless of the preceding, YOU still have a problem with General Relativity that I don't have; your scenario means the mass-ratio of plate-to-planet must change, in violation of the rules that allow reference-frame-swapping.
There are a number of issues with what's called the modern interpretation of general relativity, in that it isn't in line with Einstein. I like to think I am in line with Einstein, so please can you give details of where you get this assertion from? 

Quote from: VernonNemitz on 19/08/2009 18:41:01
By the way, I might mention that I held your opinion a number of years ago, and had to abandon it for the same reason I'm giving you now.  Some of that is described in the essay I mentioned much earlier in this Thread, http://www.nemitz.net/vernon/STUBBED2.pdf --it would be nice to get some feedback about that, thanks!)
I'll take a look at it.


Pete: I'll have a rummage via http://www.google.co.uk/search?sourceid=navclient&hl=en-GB&ie=UTF-8&rlz=1T4ADBF_en-GBGB240GB240&q=%22singularity+at+the+event+horizon%22 and get back to you later.
« Last Edit: 21/08/2009 13:51:22 by Farsight »
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #56 on: 21/08/2009 17:37:21 »
Quote from: Farsight on 21/08/2009 13:48:03
But it [mass ratio] does change. However if you follow the plate down to the surface, everything that happens to the plate also happens to you, you rods and clocks, and all other measuring devices. For example if you use a spring-powered pushing devices to assess the mass of the plate, that loses energy too. So you won't measure a reduction in the mass of the plate. It's an "immersive scale change". Your reference frame has changed, along with everything in it, including you. You don't notice the changes locally, you only notice them when you do a comparison with afar and notice the gravitational time dilation. In your new reference frame everything is moving slower, but so are you and your clocks, so you don't notice it locally. 
Nice try, but no cigar.  Sure, all those things that fall together in a gravity field experience similar-ratio mass changes, but GR requires their ratio of mass, to that of the planet, ALSO to be unchanged.

Get away from gravity for a minute and consider the in-some-ways-similar ElectroMagnetic Force.  This force can cause an electron and a proton, initially distant from each other, to fall together and form a hydrogen atom, and release some energy in the process.  Potential-energy-stored-as-mass becomes kinetic energy (with the electon getting 1836 times as much KE as the proton) becomes radiant energy.  Physicists can study the two particle independently and measure their masses.  Those masses are what physicists use in Quantum Mechanics to compute the "orbitals" in a hydrogen atom.  Now, if mass has actually been lost, when the hydroge atom is compared to the separates constituents, how can those calculations be accurate? (And they are indeed very accurate!)  Answer: The RATIO of masses of electron to proton must be identical both in the separated situation and in the atomic situation.  That means that the proton needs to lose 1836 times as much mass as the electron, during their mutual fall, even though the electron acquires 1836 times the KE.  This is still not a huge amount of mass (13.6ev) altogether, and one might wonder if the calculations/measurements are really THAT accurate...but the same sort of thing happens to a much greater degree (very measurable!) when a proton and a neutron get together to form a deuterium nucleus under the influence of the Strong Nuclear Force.  Their mass ratios are not changed by the event!

I hold the view that concepts associated with "potential energy stored as mass" must be consistent across all physical forces, if ever it is to be possible to create a Grand Unified Field Theory.  And that means the constancy of mass ratios is a requirement for Gravitation, just as it is observed for the Strong Force, and possibly observed for the EM Force.  Your mere CLAIM that the ratios must change, during gravitational interactions, has no supporting evidence, simply because the amounts of mass that convert to energy are far too tiny to measure.  But my claim has consistency-with-other-forces on its side, not to mention its being required by General Relativity, to allow easy reference-frame-switching.

I see below you asked for a reference.  I'm sorry, but my reference was a UseNet discussion that is about a decade old now, when I asked for a review of my original 1995 "Stubbed T.O.E." essay, which described a falling object as converting its own mass into the kinetic energy it acquired --- and access to the discussion appears to no longer be available.  I thorougly rewrote the essay as a result of that discussion.

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
I'm not aware that extra dimensions are required for quantum-sized black holes to exist. Black holes of any size strictly depend on the amount of mass crammed into a given volume, and nothing more than that, to the best of my knowledge.  So, again you appear to be making an arbitrary Authoritarian statement, without backing it up.
I'm not. See http://en.wikipedia.org/wiki/Micro_black_hole where it says "In familiar three-dimensional gravity, the minimum energy of a microscopic black hole is 1019 GeV, which would have to be condensed into a region of approximate size 10-33 cm. This is far beyond the limits of any current technology. "
Nice, but that has nothing at all to do with "extra dimensions", which is what you originally said (instead of talking about magnitudes of ordinary dimensions).  Please try to be more precise in the future.  (Hmmmm.... I do wonder why so much fuss was raised, though, if the requirments are actually as extreme as indicated in the Wikipedia article.)

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
Quote from: Farsight on 19/08/2009 17:15:59
... the law of cosmic censorship is just another hypothesis. 
True, but the DEFINITION of that hypothesis specifies a distinction between a singularity (more specifically, a "naked singularity") and an event horizon, which is why you are dead wrong in saying they are the same thing; physicists had specified the distinction between the two things well before the "censorship law" was proposed.
The event horison isn't the same thing as the "naked" singularity associated with cosmic censorship. It isn't a point, it's a surface.
In physics a singluarity is a place where the laws of physics no longer work, the VOLUME (not a surface) that INCLUDES a special mathematical point, where the thing exists that CAUSES the surrounding region to misbehave.  The proposed law of cosmic censorship keeps all such places INSIDE an event horizon (which is indeed a surface, despite being purely mathematical and immaterial).  That's why they are two different things, and why you are still dead wrong.

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
Hawking radiation is also about "virtual particles in the vacuum", not just event-horizon fluctuations.  The event horizon fluctuates to swallow one of a pair of virtual particles; the other becomes real and MIGHT escape the hole.
If you talk about that, talk about the situation where it swallows both virtual particles. Then the black hole is eating the vacuum energy of space. And it grows. 
False.  The one that becomes real does so at the expense of the mass of the black hole (talk to Hawking about how).  That's why the hole evaporates if enough of them escape.  So, any that do not escape just give their real-ness back to the black hole, and energy-conservation is maintained.

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
But I was not talking about virtual particles at all; I was talking about already-real particles that had closely approached the event horizon by falling toward the hole.  Anyone who thinks that gravitational time dilation and/or other effects will prevent the real particles from entering the hole is failing to take those same event-horizon-fluctuations into account.
It's just more hypothesis, Vernon. The gravitational time dilation at the event horizon is total. The time dilation is infinite. Try fluctuating infinity. 
Wrong again.  The fluctuations of the event horizon are due to the Uncertainty Principle, which is very very real.  That is, the mass of the black hole, however large, is still finite and still fluctuates due to Uncertainty, and therefore its event horizon, mathematically PRECISELY dependent upon the mass of the hole, fluctuates also.  Thus (QED) any infalling real massy particle that gets close enough WILL be swallowed by the hole.

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
Start over, and be more specific:  When you raise the plate (to, say, a shelf) you put potential energy into the plate/planet SYSTEM.
No, you don't. You're in that system. The total energy of the system hasn't changed. If it had, this system would exert more gravity than previously. It doesn't.
I repeat, we are talking about quantities of mass too tiny to measure such side-effects.  AND, we need not be part of the system to raise the plate, if you assume (an extremely unlikely but not totally irrational assumption) the plate can absorb a gravity wave that arrives from Outside and acquire kinetic energy thereby, and rise to a height in a gravitational field, similar to an electron absorbing a photon arriving from Outside and rising to a new level in an atomic electrostatic field.

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
And no, if the black hole loses mass that appears as the kinetic energy of the asteroid...
That would require action-at-a-distance. You've got mass magically leaping across a million miles of space to appear as the kinetic energy of the asteroid? No, it can't be like that. And the space surrounding the black hole doesn't lose any mass either, for the same reason. There's only one place left, Vernon.
Wrong again; your imagination is missing something.  As preparation, return to the mutually-distant electron-proton analogy.  QM describes exchanges of virtual photons between them as the basis of the EM Force between them.  While photons travel at light-speed and the distance can be considerable, there is nothing at all preventing lots of them to simultanously exist along the path between the two particles.  Focussing on the electron, it interacts with one virtual photon after another, that is already en-route between them.  It does not NEED to wait for a single virtual photon to go back-and-forth between them, before the next phase of the interaction happens.  QM for Gravitation can work the same way, no delay needed between a sequence of interactions.  Now getting to your mental block, each virtual-graviton travelling from the planet to the plate consists of POTENTIAL energy from the planet, so any that are absorbed by the plate means the plate can acquire that energy; it can become real only if planet loses mass (ditto for electron absorbing virtual photon and acquiring KE at expense of proton's mass).  Remember the virtual particle that becomes real at the expense of the mass of the black hole, if its companion particle is swallowed!  What was the connection there?  But even without referencing the Hawking Radiation hypothesis again, WE ALREADY HAVE PROVED "spooky action at a distance" is a Real Thing (see any recent development in Quantum Encryption); this is just more of the same.  What is your problem with that?  That the planet's mass should disappear due to the number of external absorptions?  Ah, but that is exactly balanced (most of the time) by the number of absorptions of virtual gravitons by the planet, from those external objects!  Any unbalance results in an acceleration, of course (so the planet and plate fall toward each other).

Quote from: Farsight on 21/08/2009 13:48:03
Quote from: VernonNemitz on 19/08/2009 18:41:01
Also, in terms of Quantum Mechanics, there are two possible answers to the question "How do gravitons get out of a black hole?"  Do you know either of those answers?)
Yes, here's one re virtual gravitons that go faster than light and break the laws of physics. http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980601a.html. Note that gravitons aren't part of the standard model. Again they're hypothetical.
That's only one of the two possible explanations, and no, it is not necessary that the laws of physics be violated if a gravtion can travel faster than light.  I'll get back to that in a minute.

The standard model does not include gravitons simply because Physics does not have a Grand Unified Quantum Field Theory yet.  Duh....

The second possible explanation for how a graviton can get out of a black hole involves the "interaction cross section" of a graviton.  We know they must be able to interact with each other; that is a requirement for consistency with General Relativity, since the existence of a gravitational field counts as mass/energy that contributes to the gravitational field.  But "being able to interact" and "always interacting" are two different things.  A low-enough rate of mutual interaction can easily suffice to let vast numbers of virtual gravitons out of a black hole, no matter how fast or slow they travel.

As you have stated so many times, gravitons are hypothetical.  That means even if they exist, we don't know for sure what they are like.  So this variation of the hypothesis is as good as any (and may be better than most):  What if a graviton is not describable as 'energy in motion"?  See, "energy in motion", such as is a photon, and also is a common hypothesis about gravitons, is required to always move exactly at light-speed.  Meanwhile, "mass in motion" is allowed to have any speed less than light-speed, and "imaginary mass in motion", should it exist, is required to always move faster than light-speed.  You are aware, I think, that if tachyons exist, the laws of physics will not be violated?  Well, a graviton doesn't necessarily have to be any of those three things in motion, and like tachyons its speed does NOT have to be associated with a violation of Physics.  See my "Simple Quantum Gravitation" knol for the details (which actually talks about very-slow gravitons, not fast gravitons, though fast ones are not ruled out).
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Offline Pmb

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If I give an object some potential energy, does its mass increase?
« Reply #57 on: 21/08/2009 19:01:30 »
Quote from: VernonNemitz
Yes, here's one re virtual gravitons that go faster than light and break the laws of physics.
Ouch! Virtual gravitons can't break the laws of nature. In fact nothing that can exist in nature can ever be said to break the laws of physics. When a virtual particle is moving faster than the speed of light it is not violating a law of nature. In fact it's quite consistent with it. When a virtual particle is moving FTL then it becomes a tachyon and the existamce of tachyons do not violate amu law of nature.
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Offline VernonNemitz

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If I give an object some potential energy, does its mass increase?
« Reply #58 on: 21/08/2009 19:10:27 »
Quote from: Pmb on 21/08/2009 19:01:30
Quote from: VernonNemitz
Yes, here's one re virtual gravitons that go faster than light and break the laws of physics.
Ouch! Virtual gravitons can't break the laws of nature. In fact nothing that can exist in nature can ever be said to break the laws of physics. When a virtual particle is moving faster than the speed of light it is not violating a law of nature. In fact it's quite consistent with it. When a virtual particle is moving FTL then it becomes a tachyon and the existamce of tachyons do not violate amu law of nature.
Please be more careful with your quotes.  The above quoted text attributed to me was actually originated by Farsight in Msg 270745.
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If I give an object some potential energy, does its mass increase?
« Reply #59 on: 21/08/2009 19:38:26 »
There's no need to tell me to be careful since I'm always careful. I'm just not perfect and as such I make mistakes.
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