Is the Einstein–Cartan theory renormalizable?

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In summary, the conversation discusses the Sciama-Kibble approach to gravity and its connection to the Yang-Mills gauge principle. The paper by Daum and Reuter explores the possibility of using a more general affine connection in gravity and its implications for renormalizability and quantization. The authors suggest that the introduction of torsion in gravity may lead to a renormalizable theory, but further research is needed to confirm this. The paper also discusses the running Immirzi parameter and its role in Asymptotic Safety.
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Specially regarding the Sciama-Kibble take on the matter; I've come by this paper http://dx.doi.org/10.1063/1.1703702 recently, and, though I haven't read it in its entirety, the reasonings it presents make a lot of physical sense to me.
I'm not terribly curious as to what happens if you use a more general affine connection than in GR (though, one will deal with this if one has to; remember that Einstein, for instance, assumed null torsion while deriving the EFE basically for mathematical simplicity - cf. The Collected Papers of Albert Einstein, VOL 6, DOC. 30, The Foundation of the General Theory of Relativity); what holds sway on me is the close analogy with the YM gauge principle - and, of course, whether or not it can be quantized.
I understand that the EC-SK equations reduce to the EFE for null torsion (if not, they most certainly should!), so there wouldn't be no a priori reason to hope the gravitational field is renormalizable here. So here we are: does the introduction of torsion magically make the theory renormalizable (and 'therefore' quantizable)? If not, what specifically prevents it from being so? (this last question is more general in scope - what makes a theory renormalizable? -, if you'll care to develop; however, I should probably mention I'm still very green in this renormalization biz, and such a discussion can get potentially off-topic).
 
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FAQ: Is the Einstein–Cartan theory renormalizable?

What is the Einstein-Cartan theory?

The Einstein-Cartan theory is a modification of Einstein's theory of general relativity that takes into account the spin of fundamental particles. It proposes that spacetime is not only curved, but also has torsion, which is a measure of how much spacetime is twisted.

What does it mean for a theory to be renormalizable?

A theory is considered renormalizable if it can accurately predict physical phenomena at all scales, from the smallest subatomic particles to the largest structures in the universe. This means that the theory is self-consistent and does not require any additional parameters or adjustments to account for different scales.

Why is the renormalizability of the Einstein-Cartan theory important?

The renormalizability of a theory is important because it indicates its validity and applicability to real-world situations. A renormalizable theory is considered more fundamental and complete than a non-renormalizable theory, as it can accurately describe physical phenomena at all scales without any inconsistencies.

Is the Einstein-Cartan theory renormalizable?

Currently, there is no consensus among scientists about the renormalizability of the Einstein-Cartan theory. Some theories, such as supergravity, suggest that it may be renormalizable, while other theories, such as string theory, indicate that it may not be. Further research and experimentation are needed to determine the exact nature of the theory.

How does the renormalizability of the Einstein-Cartan theory affect our understanding of the universe?

If the Einstein-Cartan theory is proven to be renormalizable, it could provide a more complete understanding of the fundamental forces and particles that govern the universe. It could also potentially reconcile the discrepancies between general relativity and quantum mechanics, leading to a unified theory of physics.

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