Give up GR

[Ronald Hyde]

Post reply Jul 27 (3 days ago) I've decided after much thought, that

to integrate Gravity with QM you have

to get rid of General Relativity.

Combining GR with QM is just not a viable

possibility. Space-time has to be the

flat space-time of Special Relativity.

 

Now every successful theory to data has

involved some sort of unitary representation,

SO(2), SU(1), SU(2), SU(3). SU(4). and even

higher for QM in general. All of them are some

sort of Lie, division and/or Clifford algebras.

So when Gravity gets merged with the rest of

physics, it has to be in that form too,

whether it's considered to be quantized or

not. And there's a sensible reason for that,

because any other kind of theory leads to

expressions of probabilities of greater than 1

or less than 0, which we know is a logical

absurdity.

 

Now GR was developed because Einstein believed

that a theory of Gravity had to satisfy the

principal of equivalence for acceleration and

Gravity, but acceleration is only equivalent

to Gravity to first order, acceleration has no

equivalent for tidal forces, which gravitating

bodies produce.

 

It's entirely possible to formulate Gravity so

that it occurs in flat space-time. When an atom

emits light from the Sun, it's explained that the

light is red-shifted because it has to move

in curved space-time, but you could also just say

that electrons near a massive body are lighter

than electrons away from one. And it also satisfies

the conservation of Energy this way. Of course

much has to be changed, but that's the name of the

game, make the needed changes to make a viable

theory.

 

GR not only introduces the superfluous notion of

curved space-time, it also massively complicates the

bookkeeping, ours and Natures. It also leads to the

somewhat absurd notion, that to quote chicken little,

the sky is falling. Whereas a model with flat

space-time would only have matter falling.

 

To start constructing such a theory, you could start

with the Poincare' group, which isn't really a proper

group as such, it's two groups of different dimensionality

put in the same 4 X 4 box, but that's easily corrected.

 

[Widdekind]

Could the fabric of space-time be quantized? In analogy, rather than being an ideal, smooth, continuous "rubber sheet", space-time would be a cellular mesh, which cells could deform, in only a quantized number of ways ???

[John Cuthber]

This is a grandiose thread for someone who doesn't actually understand QM as witnessed by the mistake in the first post here

 

http://www.scienceforums.net/topic/69003-the-second-black-body-problem/

[imatfaal]

!

Moderator Note

Moved to Speculations. Please take a moment to read the specific rules of that forum

[Ronald Hyde]

It was perfectly harmless where it was. I hope it wasn't moved on account of Mr. Cuthber's obvious antipathy towards everything I say. I stand by everything

I said in it, trying to put QM and GR together represents eighty years of completely failed effort, and if people continue it will be eighty more. It was placed

where it was solely to elicit some intelligent comments about it, not to violate any rules. End of story.

[John Cuthber]

"acceleration has no equivalent for tidal forces, which gravitating bodies produce. "

 

Not really. Here's a rough approximation to tidal forces caused by acceleration. To get something more like a tide would need an acceleration gradient which is an unusual state of affairs except for rotating bodies.

[Ronald Hyde]

"acceleration has no equivalent for tidal forces, which gravitating bodies produce. "

 

Not really. Here's a rough approximation to tidal forces caused by acceleration. To get something more like a tide would need an acceleration gradient which is an unusual state of affairs except for rotating bodies.

 

This cute little cartoon so clearly refutes all my reasonings about Unitarity and such that I cannot find a reply. So I'm just going to leave it to people

who read my original post to decide between it and the cartoon.

[ACG52]

I go with the cartoon.

[Phi for All]

This cute little cartoon so clearly refutes all my reasonings about Unitarity and such that I cannot find a reply. So I'm just going to leave it to people

who read my original post to decide between it and the cartoon.

!

Moderator Note

I can add a poll if you like.

[Ronald Hyde]

!

Moderator Note

I can add a poll if you like.

It wouldn't bother me at all. The results might be interesting. Add one if you wish.

On the other hand ( there is usually one ) I don't think that Nature pays any

attention to poll results, she just does whatever she wants to and leaves us to

figure it out. "Nature isn't like Lucy, she doesn't have any 'splainin' to do."

[John Cuthber]

The cartoon bits are fine, but I think the video footage at about 1 minute is more convincing.

[Phi for All]

It wouldn't bother me at all. The results might be interesting. Add one if you wish.

!

Moderator Note

It's my offer, but it would have to be your wish.

 

On the other hand ( there is usually one ) I don't think that Nature pays any

attention to poll results, she just does whatever she wants to and leaves us to

figure it out. "Nature isn't like Lucy, she doesn't have any 'splainin' to do."

!

Moderator Note

Nature won't be reading your original post, either.

[Ronald Hyde]

!

Moderator Note

It's my offer, but it would have to be your wish.

 

 

!

Moderator Note

Nature won't be reading your original post, either.

Ok, so make a poll, and yes I know that Nature doesn't read my posts.

 

Dis could be fun!

[md65536]

to integrate Gravity with QM you have

to get rid of General Relativity.

So do it. Everyone else can get rid of GR when you have a superior replacement (equal or better in ability to make predictions, precision, practicality etc).

acceleration is only equivalent

to Gravity to first order, acceleration has no

equivalent for tidal forces, which gravitating

bodies produce.

 

Spatially uniform acceleration is equivalent to a uniform gravitational field. A uniform gravitational field is not something typically found in nature as far as I know, but that's not a problem because natural gravitational fields* are locally uniform ("local spacetime is flat"*). I don't see anything wrong with that, unless you presuppose that spacetime is globally flat and what applies locally must apply globally.

 

So the equivalence principle works, either locally with acceleration at a single point equivalent to a uniform gravitational field, or over a larger area but using different acceleration at different points and a non-uniform gravitational field with tidal forces.

 

* Ignoring singularities, which are I guess an unresolved issue with GR, and a genuine opportunity for improvement (or even replacement)... but you improve something by building a replacement, not by first destroying the only thing you've got and saying "We needed something better anyway!"

Edited September 29, 2012 by md65536

[Ronald Hyde]

So do it. Everyone else can get rid of GR when you have a superior replacement (equal or better in ability to make predictions, precision, practicality etc).

 

 

Spatially uniform acceleration is equivalent to a uniform gravitational field. A uniform gravitational field is not something typically found in nature as far as I know, but that's not a problem because natural gravitational fields* are locally uniform ("local spacetime is flat"*). I don't see anything wrong with that, unless you presuppose that spacetime is globally flat and what applies locally must apply globally.

 

 

* Ignoring singularities, which are I guess an unresolved issue with GR, and a genuine opportunity for improvement (or even replacement)... but you improve something by building a replacement, not by first destroying the only thing you've got and saying "We needed something better anyway!"

 

These are very good points. I'll just say to the first one that space-time does appear to be globally flat, by what I find in the literature.

 

I actually do have a replacement in mind, it involves the substitution of a potential of a simple and familiar form, you can pull predictions out of

right away and when you look in astronomy catalogs there they are. It involves no singularities that I know of. You can start to understand things

like Eta Carinae and the dumbbell shaped nebulae that are associated with some stars. But I just wanted to see what people thought about the

idea that we should give up on GR. Basically you come away with the notion that Gravity has a lot 'more parts' than the one we are familiar with

and plays an important roll regarding structures on the large scale. I also wanted to know if something had reached the same conclusion as I had

and what reasons they might have.

[MigL]

QM takes place on the fixed background of space and time. I rather like the fact that GR gets rid of the fixed background space and time. Loop Quantum Gravity preserves those qualities of GR, but it doesn't seem to get as much exposure as SString or M theory with the only advocates that I'm familiar with being Rovelli and Smolin.

[Ronald Hyde]

QM takes place on the fixed background of space and time. I rather like the fact that GR gets rid of the fixed background space and time. Loop Quantum Gravity preserves those qualities of GR, but it doesn't seem to get as much exposure as SString or M theory with the only advocates that I'm familiar with being Rovelli and Smolin.

 

I'm definitely in favor of the 'fixed background' picture. Remember how when they put the masses of the Weak bosons in 'by hand', their equations blew up. I see exactly the

same problem with GR, it puts too many degrees of freedom into the picture and it 'blows up'. The potential I sort of described ( a smart person could figure out what it is

from my little hints ) fits right into the FB picture. Good point though and well worth replying to.