The black hole "frozen star" interpretation is the one that's right

[OnlyMe]

It isn't my label. No go and look it up.

A concentration of energy causes gravity. Again, go and look it up.

What? The photon momentum is p=hf/c. It isn't the result of some interaction.

The quantum nature of light relates to the h in E=hf or p=hf/c. The photon is a wave, not some billiard-ball.

So find something more robust.

No it can't. The active gravitational mass is the same as the inertial mass because of the equivalence principle.

Stop making up accusations based on ignorance. Go and look up active gravitational mass.

Go and look up the physics before you play the naysayer.

Farsight, the way you are using the term, active gravitational mass, is the issue.

Most of your comments above represent theoretical explanations not proven facts. Take the issue of energy and gravity. That has not been proven, though from what we observe it fits, with our currently best theoretical models, and is a necessary conclusion. The fact that it fits with theory does not make it so. Yet you constantly state it and other assumptions, as if they were fact!

Almost everything in most of these discussions is theoretical! It is how we have come to believe the universe works. Our best theories work well at describing and predicting, but they remain theories.

Yes theoretically energy, other than the inherent energy associated with massive objects, contributes to a gravitational field and that conclusion has sound basis in our theoretical interpretation of what we observe and understand to the universe... But it remains theoretical.

It is my belief that photons play a role in what we experience as gravitation, but it does not seem reasonable to me, to extend to individual photons, a gravitational field of any kind.

To do so would suggest that individual photons would interact gravitationally. Perhaps not when traveling through the relatively strong gravitational fields of massive objects, but certainly in the vast distances between galaxies where the active gravitational potential of those galaxies would be insignificant. Other than in theoretical contexts, photons do not interact directly with each other. If they did we would be unable to make any sense of what we observe of the distant universe. The picture would have become to distorted by photon gravitational interaction. Even small disturbances over the distances and time frames involved would blur the picture beyond reconstruction.

As for your insistence that I go look up anything that you have failed to provide credible evidence of... Prove it yourself!

 

[Grumpy]

OnlyMe

Almost everything in most of these discussions is theoretical! It is how we have come to believe the universe works. Our best theories work well at describing and predicting, but they remain theories.

Yes theoretically energy, other than the inherent energy associated with massive objects, contributes to a gravitational field and that conclusion has sound basis in our theoretical interpretation of what we observe and understand to the universe... But it remains theoretical.

You need to get out more, none of the effects of Relativity are theoretical only(well, gravity waves have just recently been indirectly evidenced, but actual observations of triple neutron star systems are underway), they have all been observed and documented. What, did you think physicists just took Einstein's word for it the last one hundred years or so? There is more to building giant Hadron colliders than to make pretty sparks, it also directly studies Relativistic effects of matter/mass at very near lightspeed. All of the effects that Relativity predicts have been confirmed to the point that it is perverse to deny their reality(not what Farsight thinks is reality, what Einstein thought). Even length contraction has been observed to be true. In fact, every prediction of the consequences of Relativity has been confirmed as fact, with the recent finding of B mode polarization in the CMB radiation being indirect detection of gravity waves, the LAST prediction of Relativity to be as yet unconfirmed. Where did you get the idea that this stuff was all theoretical?

Photons have no intrinsic mass, they themselves have no sort of gravitational field and are not associated with it. They are energy conduits, not energy containers, their energy is in their frequency. In fact photons do not exist. What we call a photon is a quantum of energy transiting spacetime at c, we construct the concept of the photon so we can wrap up all the characteristics of that energy packet in an easily used name. Anything that moves through spacetime at lightspeed does not experience time, it's length and the length of the dimension it is moving through is zero. The moment of it's creation and the moment it is absorbed is the same moment and it reaches it's destination at the same time as it leaves it's source, even if that is billions of lys away. A photon is really a hole through which energy passes from one surface to another. Of course, all this is only true from it's own viewpoint(in it's own frame). The rest of the Universe sees it transiting spacetime at c.

It has been argued (and is generally accepted) that the momentum of a massive object, which is a fundamental component of its relativistic mass, does not change its gravitational mass.

Yes, it does, energy of any kind is the equivalent to mass of any kind. Just like steam, water and ice are all just different forms of water, energy, plasma and matter are all just forms of energy. As massive objects get close to lightspeed their energy directly increases their mass and thus their gravity. That is why nothing with mass can ever be pushed to lightspeed, it's mass requires increased energy to further accelerate, causing more mass, that takes even more energy in a positive reinforcement loop where both mass and energy requirements reach infinity at lightspeed. Infinite energy is not available so neither is lightspeed for even the tiniest massive particle. Why do you think some real scientists were just a little worried about creating a Black Hole in the LHC? Even protons have a Schwarzschild radius. But the LHC is about two magnitudes below having that ability, I hope. And a microscopic BH would evaporate about as fast as it formed, if Hawking is right about BHs having hair.

Grumpy

 

[PhysBang]

You need to get out more,

No, he's right, all these things are very, very theoretical. The effects of relativity are all things that show up as secondary phenomena, as effects on effects. There is a lot of evidence that GR is correct, but this is complicated evidence that relies on a lot of theories being correct or approximately correct. We need to acknowledge the actual theories that are used and not simply sidestep them.

 

[OnlyMe]

OnlyMe



You need to get out more, none of the effects of Relativity are theoretical only(well, gravity waves have just recently been indirectly evidenced, but actual observations of triple neutron star systems are underway), they have all been observed and documented. What, did you think physicists just took Einstein's word for it the last one hundred years or so? There is more to building giant Hadron colliders than to make pretty sparks, it also directly studies Relativistic effects of matter/mass at very near lightspeed. All of the effects that Relativity predicts have been confirmed to the point that it is perverse to deny their reality(not what Farsight thinks is reality, what Einstein thought). Even length contraction has been observed to be true. In fact, every prediction of the consequences of Relativity has been confirmed as fact, with the recent finding of B mode polarization in the CMB radiation being indirect detection of gravity waves, the LAST prediction of Relativity to be as yet unconfirmed. Where did you get the idea that this stuff was all theoretical?

Photons have no intrinsic mass, they themselves have no sort of gravitational field and are not associated with it. They are energy conduits, not energy containers, their energy is in their frequency. In fact photons do not exist. What we call a photon is a quantum of energy transiting spacetime at c, we construct the concept of the photon so we can wrap up all the characteristics of that energy packet in an easily used name. Anything that moves through spacetime at lightspeed does not experience time, it's length and the length of the dimension it is moving through is zero. The moment of it's creation and the moment it is absorbed is the same moment and it reaches it's destination at the same time as it leaves it's source, even if that is billions of lys away. A photon is really a hole through which energy passes from one surface to another. Of course, all this is only true from it's own viewpoint(in it's own frame). The rest of the Universe sees it transiting spacetime at c.



Yes, it does, energy of any kind is the equivalent to mass of any kind. Just like steam, water and ice are all just different forms of water, energy, plasma and matter are all just forms of energy. As massive objects get close to lightspeed their energy directly increases their mass and thus their gravity. That is why nothing with mass can ever be pushed to lightspeed, it's mass requires increased energy to further accelerate, causing more mass, that takes even more energy in a positive reinforcement loop where both mass and energy requirements reach infinity at lightspeed. Infinite energy is not available so neither is lightspeed for even the tiniest massive particle. Why do you think some real scientists were just a little worried about creating a Black Hole in the LHC? Even protons have a Schwarzschild radius. But the LHC is about two magnitudes below having that ability, I hope. And a microscopic BH would evaporate about as fast as it formed, if Hawking is right about BHs having hair.

Grumpy

Grumpy,

Many of the predictions of GR have been confirmed, but they do not prove the theory, to be a fact... They demonstrate its successfulness, as a predictive tool... And they certainly do not prove any conceptual projection of the predictive success, as a description of reality.

Everything you just posted depends upon, the underlying theory as a starting point for interpreting the results. Which leaves the results and conclusions, theoretical.

Take frame dragging. It was predicted by GR and has been confirmed, most accurately by the GP-B experiment. But it does not really say anything about space or time. All it says it that there is an underlying mechanism the dynamics of which is accurately predicted by GR.

Why should that not be the case? When Einstein and those who followed his initial work, developed GR as we know it today, they were developing a model that described known details of how objects interact within the context of gravitation. They did a good job, but they never said why or how. The why and how have been overlaid as conceptual projections of the underlying model. We can imagine that space and time are like the spacetime geometry of relativity, but we have not yet proven it to be so. All we have done is proven that, that model accurately predicts things that could not be measured at the time it was developed.

Most of these current discussions have been lost in debates about what is real, rather than a discussion of the implications or application of any theory... And it seems to be too often, an argument over which one, of competing theories or conceptual interpretations of a theory, is the correct description of reality.., at a fundamental level.

If as you believe GR already explained gravitation, rather than just describing how things interact gravitationally, at everyday and larger scales, there would be no need to explore any possible underlying quantum mechanism.

AND IT WOULD NOT STILL BE CALLED, the general theory of relativity!

 

[OnlyMe]

No, he's right, all these things are very, very theoretical. The effects of relativity are all things that show up as secondary phenomena, as effects on effects. There is a lot of evidence that GR is correct, but this is complicated evidence that relies on a lot of theories being correct or approximately correct. We need to acknowledge the actual theories that are used and not simply sidestep them.

Wish I'd seen your post before responding. Clear simple and to the point.

 

[paddoboy]

No, he's right, all these things are very, very theoretical. The effects of relativity are all things that show up as secondary phenomena, as effects on effects. There is a lot of evidence that GR is correct, but this is complicated evidence that relies on a lot of theories being correct or approximately correct. We need to acknowledge the actual theories that are used and not simply sidestep them.

There will always be debates and opinions about mainstream Interpretations. Two of the greatest in Einstein and Bohr had plenty of debates on Interpretations, so its understandable that some of the general mainstream adherents will also have some disagreement.
Other than the complete nonsensical attempted rewriting of 20th century cosmology and physics by Farsight and undefined, I see the other differences in mainstream thinking as healthy.
Scientific theories are just that....except some are more set in concrete then others. I see such scientific theories as Newtonian mechanics, BB, and SR/GR as pretty well set in concrete.
I agree with Grumpy that the effects of GR are real, and I see space, time, space/time, gravity, matter, energy as all real and dependent on one another for existence. I have stated that many times.
But I have also learnt that photons, although having no rest mass, still always have momentum. This subsequently sees light as being able to contribute gravity or curve space/time ever so slightly, and most probably immeasurably so.
I see the speed of light as constant because it is massless, and if it were to be able to speed up and/or slow down, we would then by necessity, need to assign mass to it.

So in that little rundown I see myself slightly in disagreement with PhysBang/OnlyMe and slightly in disagreement with Grumpy, but as most of us are, in total disagreement with the silly notions of Farsight and undefined.
But I'm only a layman.
Any errors, alterations and/or corrections in my above thoughts?

 

[PhysBang]

I think that the effects of GR are real. I just think that they are also theoretical. Science is not always easy to think about.

 

[brucep]

No, he's right, all these things are very, very theoretical. The effects of relativity are all things that show up as secondary phenomena, as effects on effects. There is a lot of evidence that GR is correct, but this is complicated evidence that relies on a lot of theories being correct or approximately correct. We need to acknowledge the actual theories that are used and not simply sidestep them.

The predictions of GR only rely on GR. Scientific measurements associated with theoretical predictions verify the prediction, to within some reasonable measurement error, or they don't. GR has a specific domain of applicability. The effects of gravity are real. Even esoteric stuff like frame dragging.

 

[Write4U]

Yes. The energy is proportional to its wave frequency.

Which would imply movement (change). The question is " If a massless particle has no momentum, does it still have energy?"

 

[brucep]

Which would imply movement (change). The question is " If a massless particle has no momentum, does it still have energy?"

I'm pretty sure you can answer that. Do massless particles have a rest frame? A center of momentum frame were it would be zero?

 

[PhysBang]

The predictions of GR only rely on GR.

Well, no. The prediction of the perihelion shift of Mercury relies on all of Newtonian mechanics. The radar tests of time delay depend on all the engineering of radar. The binary star tests rely on some assumptions about the nature of the stars.

These might be very reasonable assumptions, but they are not GR assumptions.

 

[Write4U]

I'm pretty sure you can answer that. Do massless particles have a rest frame? A center of momentum frame were it would be zero?

I posed the question in context of a photon trapped inside the singularity of a massive BH, where momentum (movement) of anything would be so constricted as to be zero.

 

[paddoboy]

Hey Grumpy! See my post 66.
Especially the bit about light/photon creating some, albeit tiny, most likely immeasurable amount of curvature in space/time.

I posed the question in context of a photon trapped inside the singularity of a massive BH, where momentum (movement) of anything would be so constricted as to be zero.

I see the state of energy within a BH singularity, as akin to whatever existed and in whatever state, at the BB singularity.
That could be a surface of sorts, beyond the quantum/Planck realm, or just plainly a state of matter/energy at its most fundamental state. [space/time???]

 

[Grumpy]

Write4U

I posed the question in context of a photon trapped inside the singularity of a massive BH, where momentum (movement) of anything would be so constricted as to be zero.

Photons have no mass, therefore momentum cannot be applied to them. Their energy comes from their frequency, not their momentum. So they have no gravitation associated with them. Like I said, it is a more accurate picture of what photons are to say they are a hole between the two surfaces through which energy can be transferred from one to the other instantly over no distance. But that is their view of themselves, in the non-relativistic, basically motionless Universe we see them transit spacetime at c. A photon is generated by electromagnetic forces in one particle, transits space as a wave, and is converted back into electromagnetic energy when another particle absorbs them. But they still travel at c even near an Event Horizon, they are still moving along zero energy lines at c (inertial), it's just that at the EH all those paths lead inward or at best an orbit. Inside, all bets are off. No one has a good idea about what's inside an EH.

One of my professors put it like this. The photon is like the contours of a phonograph record groove. Both are waves created by energy. They are created by a powerful machine that cuts the record, but they have no power in and of themselves, only when that record meets up with a phonograph does a powerful machine turn those waves back into the sound that the original machine turned into the contours.

Grumpy

 

[paddoboy]

Write4U
Photons have no mass, therefore momentum cannot be applied to them. Their energy comes from their frequency, not their momentum.

What about solar sails?

 

[paddoboy]

Don't worry Grumpy.....I dips me lid to ya!




The following says what you just have.

""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
http://www.askamathematician.com/2010/09/q-how-can-photons-have-energy-and-momentum-but-no-mass/


Any object with mass travels slower than light and so may as well be stationary (#1).

Anything with zero mass always travels at the speed of light. But since the speed-of-light is always the speed-of-light to everyone (#2) there’s no way for these objects to ever be stationary (unlike massive stuff). Vive la différence des lois! It’s not important here, but things (like light) that travel at the speed of light never experience the passage of time. Isn’t that awesome?

The point is: light and ordinary matter are very different, and the laws that govern them are just as different.


Light and Matter: different

That being said, in 1905 Einstein managed to write a law that works whenever: E^2=P^2c^2+m^2c^4. The same year (the same freaking year) he figured out that light is both a particle and a wave and that the energy of a photon isn’t governed by it’s mass or it’s velocity (like matter), but instead is governed entirely by f, it’s frequency: E=hf, where h is Planck’s constant.

For light m=0, so E=Pc (energy and momentum are proportional). Notice that you can never have zero momentum, since something with zero mass and zero energy isn’t something, it’s nothing. This is just another way of saying that light can never be stationary.

Also! Say you have an object with mass m, that isn’t moving (P=0). Then you get: E=mc2 (awesome)!"
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

 

[Farsight]

Which would imply movement (change). The question is " If a massless particle has no momentum, does it still have energy?"

No, because what we're really dealing with is energy-momentum. A massless particle with no momentum has no energy and therefore doesn't exist.

I posed the question in context of a photon trapped inside the singularity of a massive BH, where momentum (movement) of anything would be so constricted as to be zero.

See the OP, there are issues with the nature of a black hole beyond the event horizon. You can't say with confidence that a black hole has a point-singularity within it. Besides, whatever the nature of black holes, they have a gravitational effect. The energy-momentum is still there, even if you can't see any momentum.

 

[Farsight]

Farsight, the way you are using the term, active gravitational mass, is the issue.

It isn't my term. Again, look it up, for example on Wikipedia:

"Although inertial mass, passive gravitational mass and active gravitational mass are conceptually distinct, no experiment has ever unambiguously demonstrated any difference between them..."

Most of your comments above represent theoretical explanations not proven facts. Take the issue of energy and gravity. That has not been proven, though from what we observe it fits, with our currently best theoretical models, and is a necessary conclusion. The fact that it fits with theory does not make it so. Yet you constantly state it and other assumptions...

I'm sorry OnlyMe, but relativity is just about the best-tested theory we've got. If you won't accept it, that's up to you.

Wish I'd seen your post before responding. Clear simple and to the point.

And wrong. See what brucep said, and see The Confrontation between General Relativity and Experiment by Clifford M. Will.

 

[paddoboy]

No, because what we're really dealing with is energy-momentum. A massless particle with no momentum has no energy and therefore doesn't exist.

SEE.....
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
http://www.askamathematician.com/201...m-but-no-mass/


That being said, in 1905 Einstein managed to write a law that works whenever: E^2=P^2c^2+m^2c^4. The same year (the same freaking year) he figured out that light is both a particle and a wave and that the energy of a photon isn’t governed by it’s mass or it’s velocity (like matter), but instead is governed entirely by f, it’s frequency: E=hf, where h is Planck’s constant.
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

You can't say with confidence that a black hole has a point-singularity within it. Besides, whatever the nature of black holes, they have a gravitational effect. The energy-momentum is still there, even if you can't see any momentum.

Yes you can if GR is correct, and we have no reason to doubt it as yet......
GR says that once the Schwarzchild radius is reached, further collapse is compulsory.

 

[Write4U]

Hey Grumpy! See my post 66.
Especially the bit about light/photon creating some, albeit tiny, most likely immeasurable amount of curvature in space/time.

I see the state of energy within a BH singularity, as akin to whatever existed and in whatever state, at the BB singularity.
That could be a surface of sorts, beyond the quantum/Planck realm, or just plainly a state of matter/energy at its most fundamental state. [space/time???]

Yeah, I like the word Potential a lot.. A Singularity consisting of pure Potential which at a certain treshold produces a BB.
The more I study it the more interesting the concept becomes. David Bohm spent a great deal of time on this with Einstein.

I find this equation to be very profound, Potential = That which may become reality. It means that Potential precedes every event, past, present, and future, including the BB!