Such a Nice Paper

[Dubbelosix]

Very detailed, very good paper.

It even goes into some detail why gravity is classed as a pseudoforce, something a bit rare these days but pertinent to unification attempts, or failure, using a better word. 

 

http://www.blau.itp.unibe.ch/newlecturesGR.pdf

[koti]

15 minutes ago, Dubbelosix said:

Very detailed, very good paper.

It even goes into some detail why gravity is classed as a pseudoforce, something a bit rare these days but pertinent to unification attempts, or failure, using a better word. 

 

http://www.blau.itp.unibe.ch/newlecturesGR.pdf

Why is classing gravity as a pseudoforce rare these days? Call me ignorant but theres no way I can find time do go through this large paper in detail, I’m genuinly asking.

[Dubbelosix]

Because if more scientists recognized gravity as a pseudo force, it would become...evidently clear that quantization of the psuedo field into spin 2 gravitons is complete nonsense. 

 

If it was recognized more, it would never have been an issue. I would say more scientists today accept the idea of gravitons, than not.

[koti]

11 minutes ago, Dubbelosix said:

Because if more scientists recognized gravity as a pseudo force, it would become...evidently clear that quantization of the psuedo field into spin 2 gravitons is complete nonsense. 

 Can you recommend something easly digestive to read explaining this dissonance? How do the LIGO/VIRGO findings adress this dissonance?

Edited November 19, 2017 by koti

[Dubbelosix]

You mean the observation of gravitational waves?

 

This is not a surprise, they were predicted by the classical theory of general relativity any way, predating any foundation of graviton physics. 

[koti]

36 minutes ago, Dubbelosix said:

You mean the observation of gravitational waves?

 

This is not a surprise, they were predicted by the classical theory of general relativity any way, predating any foundation of graviton physics. 

My question was how do the gravity wave LIGO findings correlate to the dissonance in aproaches to gravity mentioned above. My question might be invalid as I’m not familiar with any work explaining the „pseudoforce” aproach, I’d love to read more on it. It is fairly obvious (at least to my lame mind) that our view of gravity is currently limited and we are missing crucial parts of the big picture. Not going into any of the failed or non resolvable GUT attempts, the difference in Newtonian and GR gravity aproaches alone implies (at least to me) that we currently see only a partial view of something more complex.

Edit: Complex is not a good word, can’t find a word for current view of gravity not being whole - maybe „revealing”

Edited November 19, 2017 by koti

[Dubbelosix]

The Christoffel symbol can be 'loosely' though of as being analogous to a force in Newtons equations (where mass has been set to 1 to denote that it is a constant in this formulation):

[math]\Gamma = \frac{1}{2} \frac{\partial g_{00}}{\partial x}[/math]

Newtonian formulation of this acceleration is

[math]F = -\frac{\partial \phi}{\partial x}[/math]

However as mentioned, the gravitational force is not actually a true definition of a force as we come to expect say, in the proposed fundamental fields of nature, which are inherently complex (when quantum gravity is not) and that require quantization of field particles acting as mediators of the force (something which gravity is expected to use to form the unification theory in the opinions of many scientists). It's actually a crucial component of many theories, most notably string theory. 

Gravity is a pseudo force and can be understood in the following (neat) and (concise and short) way:

[math]\frac{d^2x^{\mu}}{d\tau^2} + \Gamma^{\mu}_{\nu \lambda} \frac{dx^{\nu}}{d \tau} \frac{dx^{\lambda}}{d\tau} = 0[/math]

where

[math]\Gamma^{\mu}_{\nu \lambda} = \frac{\partial x^{\mu}}{\partial \eta^{a}}\frac{\partial^2 \eta^a}{\partial x^{\nu}\partial x^{\lambda}}[/math]

or more compactly 

[math]\Gamma^{\mu}_{\nu \lambda} = J^{\mu}_{a} \partial_{\nu} J^{a}_{\lambda} = J^{\mu}_{a} \partial_{\lambda} J^{a}_{\nu} \equiv J^{\nu}_{a} J^{a}_{\nu \lambda}[/math]

which represents a pseudo force for gravity which makes it in the same league as the Coriolis and the Centrifugal forces.

Edited November 20, 2017 by Dubbelosix