Arp: Le Sage Gravity

[CraigS]

Originally Posted by renormalised

According to M/String Theory, gravity appears weak in our brane because most of its energy is leaking off into the higher dimensional spaces. It all depends on how the string that defines gravity is attached to the brane on which it resides. If it's a closed loop, i.e. attached at both ends to the brane, then gravity cannot leak off unless it breaks away from the brane. If it is open ended, i.e. only attached at one end of the string, then it is free to break off and leak into the higher dimensional space. You have to remember, these are just "thought pictures" to help us visualise what maybe happening. If gravity couldn't leak away from our brane, then it would appear with all its strength and the universe within the brane would collapse in on itself. The fact that the universe is here suggests that gravity leaks off into the other dimensions, so it's an open ended attachment.

Which is why it appears to us, to be weaker than the other fundamental forces? (Ie: because it leaks into other dimensions, huh ?)

[CraigS]

Originally Posted by sjastro

Curved space-time still exists if Gμν = 0. The gravitational field extends out from the central mass into empty space as per Newtonian theory.



Compensating? The greateat advantage of BBT over any of the SS theories is that the conservation of mass is not violated.

The Tμν term represents the gravitational field extending into space where matter is present such as the gravitational field of a star in a nebula.
In BBT the Tμν term has matter uniformly distributed at fixed positions in space. While m is constant, density decreases with time due to metric expansion. The field equations when extended for BBT relate to density and pressure not mass.

Steven

Doesn't the extra mass to compensate for the decrease in density result in the addition of DM ?

[renormalised (Carl)]

Originally Posted by CraigS

Which is why it appears to us, to be weaker than the other fundamental forces? (Ie: because it leaks into other dimensions, huh ?)

Correct.

[renormalised (Carl)]

Dm???

[sjastro]

Originally Posted by CraigS

Doesn't the extra mass to compensate for the decrease in density result in the addition of DM ?

In BBT matter is conserved so the total mass in the Universe is constant at any time t.

The "form" of which matter takes can change. For example in the very early history of the Universe radiation was the dominant form.

Regards

Steven

[CraigS]

Originally Posted by renormalised

Dm???

Dark Matter. Sorry.
(I've probably got my wires crossed on this one).

cheers

[renormalised (Carl)]

Ah...

As Steven has said, the amount of matter, in BBT, stays the same, only its "name" has been changed, so to speak. So, there's M = 1, all the time, no matter what stage the universe is at. But early on, it was radiation/energy, now it's matter in all its forms. It's still = 1, although it gets thinner and less dense as space expands.


With SS, there is a constant violation of the conservation or matter/energy, because new matter/energy has to be created in order to replace the old stuff which is whisked away by metric expansion. If this is happening proportionally to the expansion, then the matter/energy density of the universe remains the same. However, that would mean that the matter/energy density would be such that there'd be an increasing amount of matter being formed....to the point that it would become infinite, despite the fact it supposedly had a finite density, so the universe would collapse in on itself.

So, in SS, whilst expansion = 1, matter/energy density = 1, mass of matter tends to infinity over an arbitrarily long period of time, therefore violating their original premise, which then equals collapse.

[renormalised (Carl)]

What it would also mean is that the expansion would slow down as more matter was being formed, so the creation of new matter would have to decrease proportionally to the decrease in the expansion rate. It's a rather contrived piece of theory.

[CraigS]

Ok. Understood.

So in BBT, how does Dark Matter fit in if M =1 ?
(Is this just another form of matter ?)
Cheers

[renormalised (Carl)]

Originally Posted by CraigS

Ok. Understood.

So in BBT, how does Dark Matter fit in if M =1 ?
(Is this just another form of matter ?)
Cheers

Yes.

[CraigS]

Originally Posted by renormalised

Yes.

Ok got it.
Thanks.

Cheers

[xelasnave]

Originally Posted by renormalised

Yes and no....GR defines gravity as a warping of spacetime (so for want of a better word, a field). Gravitons are the QFT prediction for the force carries of gravity, that will fit into the Standard Model. The gravitons arise from the field itself, they don't flow through it or with it, like the particles in a colloidal solution.

The best way of thinking about gravitons is that they represent the "stress" put upon spacetime. The greater the stress, the more gravitons appear the greater the warping of spacetime.

Thanks for that Carl.

You have identified for me the difference between a push system and the GR view ..in my view it is the movement of particles (colloidal) that would create the pressure of gravity in a push system..in GR the movement of particles (gravitons) appears to me only to convey a message as to the intensity of the field...or the way space is bent...the graviton does nothing to create the force is what you are saying...so the force of gravity still is hidden from mechanical understanding.

I do think describing gravity as bent space time is rather odd.

To me GR appears as geometry that defines a grid made from three axis representing our way of seeing linear concepts with the addition of another axis or input that includes time as a component in understanding our space time "grid"... I still do not understand why the bending or manipulation of this grid makes gravity...the ball on the blanket does nothing for me by the way.

I have read what Arp had to say and it is not very much really... he seems more concerned with fitting the idea of a Le Sage universe with the current bb model... by worrying about the problems associated with creation or not of mass, the mass predicted by bb...he considered it relevant to fit Le Sages view into a bb framework and in this regard misses the main issues ...but such pursuit takes away from considering the fundamentals of the kinetics that could be involved.

I dont know very much about string theory but I do feel the extensions of logic it seems to require, in respect of explaining gravity as a weak force and the reason for such weakness,( via "leaking" of energy to another dimension) to be much greater than the visualization of a system of particles that transmit energy kinetically.

alex

[renormalised (Carl)]

You have identified for me the difference between a push system and the GR view ..in my view it is the movement of particles (colloidal) that would create the pressure of gravity in a push system..in GR the movement of particles (gravitons) appears to me only to convey a message as to the intensity of the field...or the way space is bent...the graviton does nothing to create the force is what you are saying...so the force of gravity still is hidden from mechanical understanding.

I do think describing gravity as bent space time is rather odd.

All the gravitons do is convey the gravitational force between the particles (mass) and the spacetime field, in a QFT sense. In GR, gravity is a change in the geometry of space and that is achieved by plopping mass into spacetime. They're two different ways of explaining the same effect. GR = change in geometry... QFT = exchange of gravitons produced by mass in a spacetime/gravitational field.

Another way to think of the production of gravitons is like boiling water. When it's not boiling, i.e, spacetime is flat and gravity is zero, there is no mass and therefore no gravitons. However, there is still a gravitational field...it just has a non zero quantum value. When you heat it up (progressively add mass to the system), you start to produce gravitons and the geometry of spacetime starts to bend. Add enough mass (heat it to boiling point) and you produce a black hole (lots of gravitons....extreme warping of spacetime).

The big misconception that people then have is what about gravitational waves, surely that's gravitons moving from the source to the observer??!!!. No...all a wave is doing is conveying information (in this case a disturbance in the gravitational field produced by some event) which in this instance is energy. It actually has no physical existence to speak of. The particles themselves, the gravitons, don't move very much at all. All they do is convey the energy of the wave through spacetime to the next particle alongside of them. What movement they do experience amounts to the amplitude of the gravitational wave that was generated, about their position of rest within the field.

[CraigS]

Originally Posted by renormalised

The big misconception that people then have is what about gravitational waves, surely that's gravitons moving from the source to the observer??!!!. No...all a wave is doing is conveying information (in this case a disturbance in the gravitational field produced by some event) which in this instance is energy. It actually has no physical existence to speak of. The particles themselves, the gravitons, don't move very much at all. All they do is convey the energy of the wave through spacetime to the next particle alongside of them. What movement they do experience amounts to the amplitude of the gravitational wave that was generated, about their position of rest within the field.

Sounds suspiciously the same as the "Density Wave Theory" way of describing the spiral arm shape in a galaxy ?

Interesting conversation.

Cheers

[renormalised (Carl)]

Originally Posted by CraigS

Sounds suspiciously the same as the "Density Wave Theory" way of describing the spiral arm shape in a galaxy ?

Interesting conversation.

Cheers

All waves are essentially changes in density or are the cause of the change. They are movements of energy... whether that be sound, light, gravity or whatever.

[xelasnave]

Carl that was an excellent summation and gives me confidence that I understand the current science better than I gave myself credit for but you sure helped me consolidate a few things.

So another curly question ...how many gravitons do you think we may find in a void a couple of billion light years in diameter a long way from any mass?...remember even hydrogen atoms are light years apart in this place...?

If none what happens if we introduce mass? will God have to fly in some gravitons for the occasion..or would Bojans fundamental point of gravity and mass being a set come into play?

In any event the current science gives us no mechanism as to the physical force that is gravity as I see it and if you can help me here I will be eternally grateful.

AND a question I have asked on other occasions.
GR has no problem to create the expectation of a black hole but it would seem if GR is correct it says nothing can escape once past the event horizon whereas field theory I think demands particles must be able to come and go...what do you think about what I see as an anomaly between GR and QFT on this point.

Needless to say a push universe would not have such a concern

alex

[xelasnave]

Really the major problem is for me how to "see" energy... again I need a physical reality to hold onto... could energy simply be particles so very small we consider them as nothing? That fits a push approach but imaging energy close up eludes me.

It would be easy to work the mass to energy thing if energy was simply very small particles and mass simply sticking all those energy particles into a larger more noticeable parcel.

AND no I have not been drinking or smoking or any other vice one likes to attribute thoughts from outside the box.


alex

[CraigS]

Originally Posted by xelasnave

Carl that was an excellent summation and gives me confidence that I understand the current science better than I gave myself credit for but you sure helped me consolidate a few things.

So another curly question ...how many gravitons do you think we may find in a void a couple of billion light years in diameter a long way from any mass?...remember even hydrogen atoms are light years apart in this place...?

If none what happens if we introduce mass? will God have to fly in some gravitons for the occasion..or would Bojans fundamental point of gravity and mass being a set come into play?

In any event the current science gives us no mechanism as to the physical force that is gravity as I see it and if you can help me here I will be eternally grateful.

AND a question I have asked on other occasions.
GR has no problem to create the expectation of a black hole but it would seem if GR is correct it says nothing can escape once past the event horizon whereas field theory I think demands particles must be able to come and go...what do you think about what I see as an anomaly between GR and QFT on this point.

Needless to say a push universe would not have such a concern

alex

Some things can escape black holes.
GR & QFT haven't been united (?)
Do 'pushwhateverrons' have mass ?

Cheers

[sjastro]

So another curly question ...how many gravitons do you think we may find in a void a couple of billion light years in diameter a long way from any mass?...remember even hydrogen atoms are light years apart in this place...?

If there is a void there are no gravitons. Gravitons are theoretical particles of interaction. No interaction between masses equals no gravitons.

If none what happens if we introduce mass? will God have to fly in some gravitons for the occasion..or would Bojans fundamental point of gravity and mass being a set come into play?

In any event the current science gives us no mechanism as to the physical force that is gravity as I see it and if you can help me here I will be eternally grateful.

The mechanism is straightforward. Like other bosons such photons and gluons, gravitons are created by local gauge transformations so that the Lagrangian is invariant under the symmetry rotation.
I'm surprised you are unaware of this.

AND a question I have asked on other occasions.
GR has no problem to create the expectation of a black hole but it would seem if GR is correct it says nothing can escape once past the event horizon whereas field theory I think demands particles must be able to come and go...what do you think about what I see as an anomaly between GR and QFT on this point.

Gravitons have no mass. So there is no problem of escaping, no anomalies.

Hopes this makes thing much clearer.
Oh by the way gravitons haven't been observed and mess up the mathematics.

Regards

Steven

[xelasnave]

Craig asked...
Do 'pushwhateverrons' have mass ?

Yes and no is the safest answer I can offer.
I never liked the concept that any particle can exist without mass nevertheless current science has elected to do it another way..fair enough...but I tend to think whatever particle would do the Le Sage job probably will have small mass and travel very fast ..being really small will allow a small interaction (but sufficient) with matter and allow our little particle a high top speed... they will triumph because of sheer numbers...think of a neutrino as a possible and good candidate to be a "pushwhateverron"..billions of them pass thru us with little effect ...however maybe the little effect is the push we need to power LeSages universe ... could an imbalance in neutrino flow result in gravity I wonder...

If we entertain the HB we must consider its field.
A field of HBs could provide the sort of push field Le Sage suggests for gravity...
How many HB in a void I wonder..one could think the HB field must be present irrespective of matter being present or not as I doubt a void is empty of bosens (not only HBs) .

I often wonder what could be the particle Le Sage called corpuscles or something...or pushtrons whatever... but all the nuetrinoes out there may do the job..nuetrinoes seem to be accepted as valid science.
Even the EMS may do the job (although a few changes in the current science may be needed to get that up

Anyways 'pushwhateverrons' are very small..may or may not have mass..presumably incapable of observation ... so like many things it will only be the math that will give us the valid answers.

So all we need is data and formulas to use such otherwise we may have to go with what we have with GR

alex