The Naked Scientists

The Naked Scientists Forum

Author Topic: If I give an object some potential energy, does its mass increase?  (Read 95317 times)

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
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.

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.

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.    

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.

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.   

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 »
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
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".) 

... 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.

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. 

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.)

 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
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.  

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. 

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.   

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. 

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.     

 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
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.

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.

... 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.

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.


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!)
 

Offline Pmb

  • Neilep Level Member
  • ******
  • Posts: 1838
  • Physicist
    • View Profile
    • New England Science Constortium
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.
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
You should post it for all to see, if possible.
It's too bulky, Vernon.

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. 

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. "

... 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.

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. 

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. 

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.

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.

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.

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.

..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.   

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.

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? 

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 »
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
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.

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.)

... 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.

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.

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.

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.

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).

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).
 

Offline Pmb

  • Neilep Level Member
  • ******
  • Posts: 1838
  • Physicist
    • View Profile
    • New England Science Constortium
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.
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
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.
 

Offline Pmb

  • Neilep Level Member
  • ******
  • Posts: 1838
  • Physicist
    • View Profile
    • New England Science Constortium
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.
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
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.
Give me a reference. As I said, there are significant issues with the way GR has been reinterpreted and is no longer in accord with Einstein's original. Pmb will tell you more about that.

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.
Vernon, this isn't right. You must know that p=mv and KE=1/2mv2, and that force is rate of change of momentum.  If we share momentum equally between two bodies of different masses, the lighter mass ends up moving faster, but the v2 means the kinetic energy is not shared equally. Search on this to check it out: http://www.google.co.uk/search?sourceid=navclient&hl=en-GB&ie=UTF-8&rlz=1T4ADBF_en-GBGB240GB240&q=momentum+%22kinetic+energy%22+shared

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 hydrogen 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!
It isn't as you describe. That binding energy and the emitted photon represents a loss of mass/energy, but it isn't true to say the proton loses 1836 times as much as the electron.

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.
You need to look into this further, see above, and you have to appreciate that the forces aren't identical.    

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.
It does have supporting evidence, but you're not understanding it because you don't appreciate what I mean by an "immersive scale change". What I'm saying is vindicated by the Pound-Rebka experiment and the GPS clock adjustment, both of which are extremely sensitive. Do you remember what I said about a spinning plate? If it's spinning extremely fast it has more energy. Move this into an extremely time-dilated environment, and it's spinning slower, and hence has lost energy. Then I said you should consider a plate to be made up of "tiny spinning plates" called electrons and protons. It's really simple Vernon, but it's not what you've been taught.
 
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 thoroughly rewrote the essay as a result of that discussion.
Shame. You were on the right track then, and got talked out of it. The kinetic energy of the falling plate comes from somewhere. It maybe comes out of the planet. It maybe comes out of the space surrounding the planet. Or it maybe comes out of the plate. The first two options demand magical-mysterious action-at-a-distance and an undetectable transfer of energy through some invisible undetectable particles. There is no scientific evidence to support this.

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.)
I said I didn't think quantum black holes are going to get created in the LHC and I've given you ample reason.  

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.
You're being too argumentative, and you're defending your argument with too many hypotheticals.

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.
I can only reiterate that a significant number of physicists consider Hawking radiation to be an unproven hypothesis. You can't use it to assert the truth of falsehood of something else.  

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.
This is not what the uncertainty principle says. Check it out: http://en.wikipedia.org/wiki/Uncertainty_principle

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.
Anything arriving from outside the system adds energy to the system. When it lifts the plate, it gives the plate potential energy. The energy goes into the plate. Hence its mass is increased. Simple.  

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.
And they're virtual. They aren't real. They're a calculation tool. Feynman didn't ascribe them the same sort of reality as you do. You know what they really are? Collectively they're something called the evanescant wave.

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?
The same as Newton's:

“That gravity should be innate, inherent, and essential to matter, so that one body may act upon another at a distance through a vacuum, without the mediation of anything else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity that I believe no man who has in philosophical matters a competent faculty of thinking can ever fall into it”

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).
Gravitons remain hypothetical, and virtual gravitons even more so.

That's only one of the two possible explanations, and no, it is not necessary that the laws of physics be violated if a graviton can travel faster than light.  I'll get back to that in a minute.
I dispute that. And do note that I've got a couple of old friends backing me up on this. One is Isaac Newton, and the other is Albert Einstein.

The standard model does not include gravitons simply because Physics does not have a Grand Unified Quantum Field Theory yet.
And when it does, this grand unified theory will be one where "the concept of field is no longer appropriate". And it will not include gravitons.

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.
No, we don't "know" they interact with one another. We don't even know that they exist. It's all just hypothesis on top of hypothesis.

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..
Good stuff Vernon. This is more like it.

..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.
Aaaargh!

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).
Like I said, I'll check it out.

Vernon, these posts are getting too long. I'm giving you a great deal of my time here but you're going to extraordinary lengths to avoid the obvious: the kinetic energy of the falling plate comes from that plate. The plate had the potential energy. We gave it to the plate. Go with the flow of this. Once you do, everything gets a whole lot simpler. Apologies, Friday night is calling, and the wife. Gotta go.
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
Pete: sorry I haven't back to you before now. Here's a little something on the Schwarzschild singularity.

http://everything2.com/title/Schwarzschild+metric

See where he says:

"Well, it is a little more serious than that in fact: a particle observed (from outside) to fall towards the Schwarzschild Singularity will appear to take an infinite time to reach it, whereas the particle itself will think that it did reach r=2M in a finite time. Something odd is definitely happening here, and the conclusion to be drawn is that time (t) is not a sensible coordinate to be dealing with in this region (there is a better coordinate system - see below)".

There isn't a better coordinate system. That better coordinate system is counting time on a stopped clock. Hence we get back to the original frozen star concept. See http://en.wikipedia.org/wiki/Black_hole and note this section:

"Because of this property, the collapsed stars were briefly known as "frozen stars,"[citation needed] because an outside observer would see the surface of the star frozen in time at the instant where its collapse takes it inside the Schwarzschild radius. This is a known property of modern black holes, but it must be emphasized that the light from the surface of the frozen star becomes redshifted very fast, turning the black hole black very quickly. Many physicists could not accept the idea of time standing still at the Schwarzschild radius, and there was little interest in the subject for over 20 years.

In 1958, David Finkelstein introduced the concept of the event horizon by presenting Eddington-Finkelstein coordinates, which enabled him to show that "The Schwarzschild surface r = 2 m is not a singularity, but that it acts as a perfect unidirectional membrane: causal influences can cross it in only one direction".[6] This did not strictly contradict Oppenheimer's results, but extended them to include the point of view of infalling observers. All theories up to this point, including Finkelstein's, covered only non-rotating black holes".


But time does stand still. Every observer in this universe will agree on it. The time dilation at the event horizon is infinite. The proper time of the infalling observer never ever happens. Never. Finkelstein was wrong. The black hole ends up more like a gravastar, see http://en.wikipedia.org/wiki/Gravastar. See where it says "This region is called a gravitational vacuum, because it is a void in the fabric of space and time". What you end up with is even more of a hole that the traditional black hole. The event horizon is the end of events, and the end of space. It's a spherical surface of infinite time dilation and infinite radial length contraction, and you can never get past it.   
« Last Edit: 24/08/2009 09:05:24 by Farsight »
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
Several of your remarks in the last message stressed the hypothetical nature of certain things.  But one variety of thing is not hypothetical at all: virtual particles.  WHILE they exist, they are exactly as real as ordinary particles.  And their temporary existence can detectably though indirectly affect real things; see the "Casimir Effect" for details: http://en.wikipedia.org/wiki/Casimir_effect

If you want to argue that virtual particles are ignorable/merely-hypothetical, then you are fighting (a losing fight!!!) against the Uncertainty Principle.  The UP requires that even a volume of space that is absolutely empty of any real particles or energy must nevertheless have an Uncertain energy content.  Therefore virtual particles must exist; they are the form taken by those Uncertain energy-variations, and the Casimir Effect is the proof they exist everywhere and all the time.

Next, regarding piling hypothesis on hypothesis, that's not true.  It is perfectly straightforward logic, that if gravitons exist, they must be able to interact with each other.  The key point is that a Quantum Mechanics theory for Gravitation must be able to yield results that are basically identical to the results of General Relativity; we know the GR results are quite realistic, and a QM theory cannot be less realistic and also be correct.  So, if a gravitational field counts as a type of mass/energy that can add to a gravitational field, then in terms of virtual gravitons making up that field, the virtual gravitons must be sources of additional virtual gravitons, in order for that description to be consistent with the GR description.  And Time Reversal Symmetry requires that anything that can emit something must also be able to absorb it (the essence of "interact").  Simple ironclad logic; only one hypothesis needed, the one that says it ought to be possible to devise a QM theory for Gravitation, involving gravitons, consistent with observations (not to mention GR).  Do note that gravitons are supposed to be the smallest possible type of gravity wave (the theoretical existence of that generic thing appears to be supported by the measured behavior of close-orbiting neutron stars: http://www.astro.cornell.edu/academics/courses/astro201/psr1913.htm ).  Because of various Conservation Laws, gravity waves are not considered to be any more hypothetical than radio waves from your favorite AM station.  We know that those kinds of radio waves are made up of lots of photons; we can logically deduce, if things like Space and Time are themselves quantized, then there must be a minimum-size gravity wave; why NOT call it a "graviton"?  (If spacetime is not quantized, then of course there would be not have to be a limit to smallness of a gravity wave; they would not need to exist as quanta.) (Getting off-track now, there is a Law Conservation of Information that physicists have been taking very seriously in recent decades, and one problem with that has involved black holes.  If they can evaporate via Hawking radiation, how does the information that fell into them get out again?  http://www.space.com/news/hawking_bet_040716.html  --The answer relates to space-time being quantized.  YOU probably won't be impressed if you think that Hawking Radiation can't exist; my only point here is that QM has survived another test of overall self-consistency --with the consequence that gravitons are more likely to actually exist than to be merely hypothetical.  For more on Information Conservation and quanta, try to get this book: http://www.librarything.com/work/378995 --and this link might count as a sample of the material: http://www.springerlink.com/content/b43670p553581tv8/  )

Another aspect of "piling" hypotheses is presented by you in this statement:
Gravitons remain hypothetical, and virtual gravitons even more so.
Sorry, but if they exist at all, then both types, virtual and real, will exist.  Period.  Any particle that can exist at all can also exist virtually; any particle that exists virtually can become real if it absorbs the appropriate quantity/type of real energy.  There is no "hypothetical" AT ALL, regarding virtual existence; one of the best pieces of evidence involves gamma-ray photons that turn into particle-pairs; pair-production is maximized at certain energies called "resonant energies".  Resonant with what, eh?  Virtual particles!

Finally, from your message #270459 (Aug 19, 2009, 17:15:59), I quote (regarding quantum black holes):
"None will be produced by such a collision, because the required extra dimensions do not exist."
  You have yet to show why any extra dimensions are required.  You have presented OTHER reasons why quantum black holes will not be created, which I find satisfactory.  But don't try to make me think you didn't say what you actually said!

After your faulty mind-set has been corrected, regarding the above matters, then we can move on to other aspects of the discussion.
« Last Edit: 24/08/2009 19:43:20 by VernonNemitz »
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
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.
This is not what the uncertainty principle says. Check it out: http://en.wikipedia.org/wiki/Uncertainty_principle
You need to see the proper part of that page:  http://en.wikipedia.org/wiki/Uncertainty_principle#Energy-time_uncertainty_principle
(want more evidence?  The units of Planck's Constant are in "erg-seconds", i.e., energy multiplied by time)
To the extent that mass is equivalent to energy, the mass of a black hole will indeed fluctuate on the very-small time scale.  Meanwhile, as I stated previously, the event horizon is purely mathematical in its description and is EXACTLY correlated with the mass of the hole.  Therefore if the mass fluctuates, so does the event horizon.  The hole will be perfectly able to gobble any close-enough thing, regardless of General Relativity's time-slowing effects.
« Last Edit: 25/08/2009 20:55:34 by VernonNemitz »
 

Offline Ron Hughes

  • Sr. Member
  • ****
  • Posts: 363
    • View Profile
Back to the original question. Please tell me if I'm wrong. Any particle, group of particles or molecules accelerated in any way will gain mass, not because of the new velocity but because of the acceleration.

I find it difficult to believe that a clock in a mathematical boundary of an event horizon is stopped. If I'm observing this clock from outside the horizon it may appear stopped to me but I also know that if I zoom down to the clock I will find it happily ticking along. Not only that, as we fall toward the center it will still be ticking. If I look back at the rest of Universe I will see everything moving very very fast. Gravity can escape from a BH because time dilation can escape.
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
Back to the original question. Please tell me if I'm wrong. Any particle, group of particles or molecules accelerated in any way will gain mass, not because of the new velocity but because of the acceleration.
Ummm, the original question was about potential energy, not about accelerated particles.

Regarding already-accelerated particles, they have extra mass as seen from the perspective of a relatively stationary frame of reference.  There is no way, from the perspective of the accelerated particles, to detect that increase in mass, though.  For example, consider that galaxies very far away have a spectrum that indicates they are moving at a large fraction of light-speed.  Pick one at random.  We might think its mass has increased as a result of its speed, relative to us.  On the other hand, US relative to IT could be considered as having increased in mass, instead!  Do you suddenly feel more massive as a result of that realization?  No?  Like I said, there is no way to tell, at least when constant velocities are involved.  You are right, though, in that it is the acceleration toward a high velocity, and especially the energy it takes to cause that, that is the ultimate source of relativistic mass.

Please note some of this discussion is about locations of objects inside a gravitational field gradient.  Objects that are allowed to fall in that gradient will of course accelerate and acquire kinetic energy and relativistic mass in consequence.  But that kinetic energy has to come from somewhere; the explanation being talked about here concerns mass as the "storage" form of the potential energy that becomes kinetic energy.

I find it difficult to believe that a clock in a mathematical boundary of an event horizon is stopped. If I'm observing this clock from outside the horizon it may appear stopped to me but I also know that if I zoom down to the clock I will find it happily ticking along. Not only that, as we fall toward the center it will still be ticking. If I look back at the rest of Universe I will see everything moving very very fast. Gravity can escape from a BH because time dilation can escape.

Not bad, except for that last bit.  In terms of General Relativity and curved space-time, a black hole is not a problem; ANY mass is just a mass causing curvature.  It is only Quantum Mechanics, should it be applied to explain gravity, that has a problem.  Its generic explanation for a force involves something called "exchange particles", and it is those particles that somehow have to get out of a black hole to interact with other things.
 

Offline Ron Hughes

  • Sr. Member
  • ****
  • Posts: 363
    • View Profile
Time is relative to the observers frame of reference which we all know. A clock in another moving frame of reference slows with respect to our observer.If we had a one kg block setting on a frictionless surface and apply a force of 1kg.m/sec^2 it will accelerate at 1m/sec^2. The only way to increase this acceleration is to increase the applied force OR slow the observer's clock. Isn't this exactly what happens in a gravity well?”

I hope the reader will agree that any particle can be considered it's own clock ( an observer ) and that a clock even one nanometer higher in a gravity well will run slightly faster than a clock one nanometer lower. Suppose we had a frictionless tube, one meter long, whose inside diameter is just large enough to allow a diatomic hydrogen molecule to move freely up and down in the tube. We fill the tube with diatomic hydrogen at STP and stand the tube up perpendicular to the surface of the Earth. Each molecule is moving up and down in the tube colliding with the molecule above and below. Let’s observe the path of a particular molecule which we call B. The molecule above we call A and the one below we call C. We start watching B as it moves down the tube toward C with velocity d/t. The molecule B (clock/observer) will calculate it's momentum, at the instant before the collision with C, using it's clock which is running slightly slower than when it collided with A. B will find it's momentum at C to be greater than the momentum of the collision with A. Doesn't this suggest that gravity is strictly a function of time dilation? Inertial forces can be considered as the same process. Particles accelerated in free space exhibit the same time dilation which would explain why we can't tell the difference between inertial forces and gravitational forces.
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
Time is relative to the observers frame of reference which we all know. A clock in another moving frame of reference slows with respect to our observer.If we had a one kg block setting on a frictionless surface and apply a force of 1kg.m/sec^2 it will accelerate at 1m/sec^2. The only way to increase this acceleration is to increase the applied force OR slow the observer's clock. Isn't this exactly what happens in a gravity well?
Please remember that in General Relativity, gravity involves curvature not just of space only but of space-time, caused by the presence of a mass.  You are describing things associated with gravity's distortion of time.  And no, you cannot conclude from that, that gravity is a consequence of the distorted time.

Another problem that Quantum Mechanics has, with respect to trying to describe gravity, involves the need to provide "matching" explanations for such things as time dilation in a gravity well.  A simple explanation brings potential-energy-stored-as-mass into the picture.  An object that loses mass while falling into a gravity well, due to potential energy being converted to kinetic energy, is an object that will have less mass at the bottom of the well, after it hits bottom and its kinetic energy is lost/radiated-away.  And in QM a lesser mass can be associated with a lesser vibration rate (per the wave-particle duality), or, in terms of what you wrote that I didn't quote, a slower internal clock.  (Note Farsight and I have been arguing about some of the details of that idea, but not the main idea itself.)
 

Offline Ron Hughes

  • Sr. Member
  • ****
  • Posts: 363
    • View Profile
So my post is wrong, not because of the logic but because it's not a QM explanation? Do you ever question the fact that QM must invent hypothetical particles to explain mass and gravity? When asked to explain the gravitational anomalies they invent dark matter and energy? The propagation of light requires virtual particles that have no proofs in reality? Pretty neat, they invent Qm and when it can't explain something just add a particle.Now if someone else pulls a stunt like that they are grasping at straws to maintain their theory. Suppose for a second that my post above is correct. It would mean that the value of F = ma is not the same everywhere. That would explain the Pioneer anomaly and the rotation curve of galaxies, but I guess one should never use Occam's razor in science. A quote from Newton, "We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances. Therefore, to the same natural effects we must, so far as possible, assign the same causes."
« Last Edit: 26/08/2009 16:15:30 by Ron Hughes »
 

Offline PhysBang

  • Hero Member
  • *****
  • Posts: 588
  • Thanked: 14 times
    • View Profile
So my post is wrong, not because of the logic but because it's not a QM explanation? Do you ever question the fact that QM must invent hypothetical particles to explain mass and gravity? When asked to explain the gravitational anomalies they invent dark matter and energy? The propagation of light requires virtual particles that have no proofs in reality? Pretty neat, they invent Qm and when it can't explain something just add a particle.Now if someone else pulls a stunt like that they are grasping at straws to maintain their theory. Suppose for a second that my post above is correct. It would mean that the value of F = ma is not the same everywhere. That would explain the Pioneer anomaly and the rotation curve of galaxies, but I guess one should never use Occam's razor in science. A quote from Newton, "We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances. Therefore, to the same natural effects we must, so far as possible, assign the same causes."
And Newton applied this principle by identifying causes as those theoretical principles that we could get agreeing measurements of from multiple sources. Does you explanation have any measurement behind it? Do you explain the Pioneer anomaly and the differences in galaxy rotation curves with a deviation from Newtonian mechanics that has accurate and agreeing measurements from both phenomena?
 

Offline VernonNemitz

  • Full Member
  • ***
  • Posts: 62
    • View Profile
So my post is wrong, not because of the logic but because it's not a QM explanation?
I'm keeping my explanations of GR stuff separate from QM stuff; please do not confuse them.  Your post was wrong partly because its logic fails to explain the source of time-dilation for different gravity wells.
Each molecule is moving up and down in the tube colliding with the molecule above and below. Let’s observe the path of a particular molecule which we call B. The molecule above we call A and the one below we call C. We start watching B as it moves down the tube toward C with velocity d/t. The molecule B (clock/observer) will calculate it's momentum, at the instant before the collision with C, using it's clock which is running slightly slower than when it collided with A. B will find it's momentum at C to be greater than the momentum of the collision with A.
Also, of course, there is the fact that for molecule B to reach A after colliding with C, it has to climb a gravitational field gradient.  You are aware that anything rising in such a gradient tends to lose velocity/momentum (converts to potential energy)?  So, no need to invoke time-dilation there as a cause for its lesser momentum (and that would be backward, anyway, since clocks tick FASTER higher-up in a gravity gradient).

Regarding dark matter and dark energy, these things are proposals resulting from analyzing lots of cosmological data.  Aspects of those proposals are subject to change as more data is gathered/analyzed.  To the extent that current data/analysis is real and correct, then that means we have observed some things that cannot be explained without modifying in some way the usage of existing theories such as General Relativity (for example, by putting a proposal by Einstein regarding a "cosmological constant" back into the theory).  And, adding new/oddball types of matter or energy are ways of extending the application of existing theory without actually modifying the theory itself.

Back to QM.  It has a long history of inventing particles and later discovering them (the first was the anti-electron or positron, but also see the stories behind neutrinos and pions and the Weak Force exchange particles and all the quarks).  Do not assume that just because a proposed particle is currently hypothetical, it must be ignorable.  When such a proposal is widely accepted --such as is currently true for the Higgs boson, which was accepted enough to get the Large Hadron Collider built specifically to find it-- there MUST be good reason for it (usually it's necessary for theoretical logical self-consistency).  If dark matter and/or dark energy exists (and the current interpretation of the data can be taken to mean: "it exists on a large scale and has certain large-scale properties"), then it should be relatively obvious that it would have small-scale properties, also.  QM, of course, is the essence of our study of small-scale properties.  Why shouldn't QM researchers propose new particles?
« Last Edit: 26/08/2009 17:37:22 by VernonNemitz »
 

Offline Ron Hughes

  • Sr. Member
  • ****
  • Posts: 363
    • View Profile
You are correct I don't, but if someone with the necessary skills doesn't try using the idea we will never know. QM uses the graviton, a hypothetical particle, my idea has none. Because the vast majority of scientists buy into the standard model that makes it right. In 1905 the vast majority thought time was a constant. The reason for time dilation, I suspect has something to do with the density of electromagnetic radiation around matter. An impossible test of that would be if we could take any matter down to absolute zero it's weight should be zero.
 

Offline lightarrow

  • Neilep Level Member
  • ******
  • Posts: 4586
  • Thanked: 7 times
    • View Profile
Back to the original question. Please tell me if I'm wrong. Any particle, group of particles or molecules accelerated in any way will gain mass
No, mass stays constant (it's also called "invariant" mass exactly for this reason).
 

Offline lightarrow

  • Neilep Level Member
  • ******
  • Posts: 4586
  • Thanked: 7 times
    • View Profile
Please note some of this discussion is about locations of objects inside a gravitational field gradient.  Objects that are allowed to fall in that gradient will of course accelerate and acquire kinetic energy and relativistic mass in consequence. 
Of course they will accelerate even in the absence of any gradient, provided there is a gravitational field...
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
Several of your remarks in the last message stressed the hypothetical nature of certain things.  But one variety of thing is not hypothetical at all: virtual particles.  WHILE they exist, they are exactly as real as ordinary particles.  And their temporary existence can detectably though indirectly affect real things; see the "Casimir Effect" for details: http://en.wikipedia.org/wiki/Casimir_effect
There's certainly something real there, Vernon. The Casimir effect is real. But those vitural particles are virtual. It's wrong to ascribe them the degree of reality that you do.  

If you want to argue that virtual particles are ignorable/merely-hypothetical, then you are fighting (a losing fight!!!) against the Uncertainty Principle.  The UP requires that even a volume of space that is absolutely empty of any real particles or energy must nevertheless have an Uncertain energy content. Therefore virtual particles must exist; they are the form taken by those Uncertain energy-variations, and the Casimir Effect is the proof they exist everywhere and all the time.
Like I said, there's something there that's real, and that energy is real. But to claim that this is proof of virtual particles popping in and out of existence is on a par with saying it proves the existence of tiny dancing angels. Think of virtual particles as the evanescent wave.  

Next, regarding piling hypothesis on hypothesis, that's not true.  It is perfectly straightforward logic, that if gravitons exist, they must be able to interact with each other. The key point is that a Quantum Mechanics theory for Gravitation must be able to yield results that are basically identical to the results of General Relativity; we know the GR results are quite realistic, and a QM theory cannot be less realistic and also be correct. So, if a gravitational field counts as a type of mass/energy that can add to a gravitational field, then in terms of virtual gravitons making up that field, the virtual gravitons must be sources of additional virtual gravitons, in order for that description to be consistent with the GR description.
Vernon, gravitons do not exist. A photon conveys energy. Energy causes gravity. There are no actual gravitons zipping back and forth between a photon and everything else. And nor are there any virtual gravitons. It's all hypothesis.

And Time Reversal Symmetry requires that anything that can emit something must also be able to absorb it (the essence of "interact").  Simple ironclad logic; only one hypothesis needed, the one that says it ought to be possible to devise a QM theory for Gravitation, involving gravitons, consistent with observations (not to mention GR).  Do note that gravitons are supposed to be the smallest possible type of gravity wave (the theoretical existence of that generic thing appears to be supported by the measured behavior of close-orbiting neutron stars: http://www.astro.cornell.edu/academics/courses/astro201/psr1913.htm ). Because of various Conservation Laws, gravity waves are not considered to be any more hypothetical than radio waves from your favorite AM station.
Radio waves are quite measurable. Photons are detectable. Gravity is detectable. Gravitons are not. And nor are virtual gravitons.

We know that those kinds of radio waves are made up of lots of photons; we can logically deduce, if things like Space and Time are themselves quantized, then there must be a minimum-size gravity wave; why NOT call it a "graviton"? (If spacetime is not quantized, then of course there would be not have to be a limit to smallness of a gravity wave; they would not need to exist as quanta.) (Getting off-track now, there is a Law Conservation of Information that physicists have been taking very seriously in recent decades, and one problem with that has involved black holes. If they can evaporate via Hawking radiation, how does the information that fell into them get out again?  http://www.space.com/news/hawking_bet_040716.html  --The answer relates to space-time being quantized. YOU probably won't be impressed if you think that Hawking Radiation can't exist; my only point here is that QM has survived another test of overall self-consistency --with the consequence that gravitons are more likely to actually exist than to be merely hypothetical.  For more on Information Conservation and quanta, try to get this book: http://www.librarything.com/work/378995 --and this link might count as a sample of the material: http://www.springerlink.com/content/b43670p553581tv8/  )
Again, Hawking radiation is hypothesis. We were talking about where the energy of a falling plate comes from. You're defending your stance that it doesn't come from the plate, with hypothesis after hypothesis, for which no evidence exists whatsoever. Your stance is not supported. Mine is, by the spinning plate, which spins at a reduced rate in a region of gravitational time dilation, the same applying to its component electrons and their spin. It's really very simple.  

Another aspect of "piling" hypotheses is presented by you in this statement:
Gravitons remain hypothetical, and virtual gravitons even more so.
Sorry, but if they exist at all, then both types, virtual and real, will exist. Period. Any particle that can exist at all can also exist virtually; any particle that exists virtually can become real if it absorbs the appropriate quantity/type of real energy. There is no "hypothetical" AT ALL, regarding virtual existence.
It is hypothesis.

One of the best pieces of evidence involves gamma-ray photons that turn into particle-pairs; pair-production is maximized at certain energies called "resonant energies". Resonant with what, eh? Virtual particles!
It's no proof of virtual particles the way you think of them.  

Finally, from your message #270459 (Aug 19, 2009, 17:15:59), I quote (regarding quantum black holes):
"None will be produced by such a collision, because the required extra dimensions do not exist."
  You have yet to show why any extra dimensions are required. You have presented OTHER reasons why quantum black holes will not be created, which I find satisfactory. But don't try to make me think you didn't say what you actually said!
See http://en.wikipedia.org/wiki/Micro_black_hole and please do your own research. This extra dimensions thing isn't my claim.

After your faulty mind-set has been corrected, regarding the above matters, then we can move on to other aspects of the discussion.
My mindset isn't faulty, Vernon. The energy of the falling plate came from the plate.
 

The Naked Scientists Forum


 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums