Can Quantum Gravity Serve as a Theory of Everything?

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Quantum Gravity is debated as a potential Theory of Everything (TOE), with the idea that combining Quantum Field Theory (QFT) and General Relativity (GR) could lead to a comprehensive explanation of the universe. However, it may only serve as a theory of "almost everything," possibly failing to address phenomena like dark energy. Current theories, including Loop Quantum Gravity (LQG) and String Theory, are not yet capable of deriving QFT or GR, leaving fundamental questions about the quantum and relativistic nature of the universe unanswered. Some discussions suggest that String Theory could potentially model complex systems like causal fermion systems, indicating a broader application. Ultimately, the quest for a true TOE remains ongoing and complex.
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I'm wondering if Quantum Gravity is expected to be a Theory Of Everything (TOE)? Can we expect that if we combine QFT with GR to get Quantum Gravity, will that be a TOE that explains GR and QFT?
 
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I think is should be a candidate for a TOE, since QFT describes everything other than gravity.
It's as likely though that it could turn out to be a theory of 'almost everything', for example it might not adequately explain dark energy.
 
As of now, it's not only not a TOE, its' not even a T.
 
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It seems to me that any development of a theory assuming QFT and GR are true will not enable us to then derive either QFT or GR. We might be able to answer some questions about black holes and big bangs. But we still won't know why the universe is quantum mechanical or general relativistic. So what should we expect to find out with LQG or Stringtheory?
 
friend said:
It seems to me that any development of a theory assuming QFT and GR are true will not enable us to then derive either QFT or GR. We might be able to answer some questions about black holes and big bangs. But we still won't know why the universe is quantum mechanical or general relativistic. So what should we expect to find out with LQG or Stringtheory?
i thought string theory can rederive GR on its own?
 
black hole 123 said:
i thought string theory can rederive GR on its own?
Causal fermion system
Here's another possibility I literally just found. I see string theory as a theory of anything, so I wonder if string theory could be used to model this "causal fermion system" as well?

"Taking the concept seriously that the states of the Dirac sea form an integral part of the physical system, one finds that many structures (like the causal and metric structures as well as the bosonic fields) can be recovered from the wave functions of the sea states. This leads to the idea that the wave functions of all occupied states (including the sea states) should be regarded as the basic physical objects, and that all structures in space-time arise as a result of the collective interaction of the sea states with each other and with the additional particles and "holes" in the sea. Implementing this picture mathematically leads to the framework of causal fermion systems." - Putting the "darkness" of matter right in the core of its basis?
 
"Supernovae evidence for foundational change to cosmological models" https://arxiv.org/pdf/2412.15143 The paper claims: We compare the standard homogeneous cosmological model, i.e., spatially flat ΛCDM, and the timescape cosmology which invokes backreaction of inhomogeneities. Timescape, while statistically homogeneous and isotropic, departs from average Friedmann-Lemaître-Robertson-Walker evolution, and replaces dark energy by kinetic gravitational energy and its gradients, in explaining...

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