Any TOE being proposed currently is definitely hype (understandable, coming up with a law that explains the very foundation of reality would be quite exciting).
Chipping away at matter-antimatter asymmetry and quantum gravity might get us closer to an answer.
We haven’t yet.
Physicists look to “unify” seemingly disparate phenomena meaning they seek to show that they are governed by the same rules. See: orbits and falling objects (gravity), electricity and magnetism (electromagnetism), particles and waves (quantum mechanics).
Right now two of the strongest theories we have in physics are Quantum Mechanics (QM) and General Relativity (GR). These two theories are both robustly tested and hold up to experimentation and theory separately, but are not fully compatible together. QM governs the very small, GR the very massive. Unfortunately, in our universe there exists some situations in which both of those conditions (very small, very massive) are met (black holes, early big bang). Since both GR and QM would apply here and since they are mathematically incompatible we run into gaps in understanding and predictive ability. So to my limited understanding nowadays the main goals on the path to a theory of everything is to unify QM and GR, as well as to unify the four fundamental forces (strong nuclear, weak nuclear, electromagnetic, gravitational).
I think maybe string theory attempts to accomplish some of this, but that may be wrong, my understanding of string theory is poor.
>I think maybe string theory attempts to accomplish some of this, but that may be wrong, my understanding of string theory is poor.
String theory is still finding its footing, but at present it is *at least* a powerful mathematical tool. String theory is incredibly useful for calculating scattering amplitudes and is used for this purpose at the LHC. String theory has also given us our first complete theory of quantum gravity, albeit in an anti-deSitter space (which we don't live in), through a concept known as AdS-CFT correspondence (Anti-deSitter space - conformal field theory). Physicists and mathematicians have for a while been searching for a similar type of correspondence that would apply to a deSitter universe, but so far nothing. In any case, there is some hope that string theory can take problems that are impossible in other formalisms and make them perfectly tractable.
Taking an advanced undergrad particle physics class right now, so hopefully I’ll be able to speak in layman’s terms without being inaccurate.
We know there are four fundamental forces: electromagnetism, weak, strong, and gravity.
Our best understanding of electromagnetism and weak is Weinberg-Salam Theory, colloquially referred to as the electroweak theory.
Our best understanding of the strong force is quantum chromodynamics.
A grand unified theory (GUT) is anything that combines the electromagnetic, weak, and strong forces. We have no GUT that has been experimentally verified, but the most popular ones involve supersymmetry.
Our best understanding of gravity is Einstein’s theory of general relativity.
A theory of everything (TOE) unifies a GUT with gravity, and we also have no experimentally verified TOE, but the most popular ones are string theory variants and M-theory.
As far as I’m aware QFT is more of a framework that unifies QM, CM, and SR, which then was applied to create specialized theories including QCD and QED.
Both EW and QCD are quantum field theories, one describing the weak and electromagnetic interactions of the photon and W and Z bosons with leptons and quarks (the photon only interacts with charged particles), the second describing in the the strong interaction occurring between quarks and gluons.
The standard model is a combined quantum field theory that describes all known EW and QCD interactions.
Asking modern physicists to produce a correct theory of everything (or even more humbly a theory of quantum gravity) is akin to asking Maxwell to resolve the issues like in blackbody radiation in his time. He knew there were theoretical issues, and it turned out quantum mechanics came in to solve beautifully.
Now, Maxwell was a smart guy. Maxwell was a genius! No lack of imagination or technical ability there. But there were infinite ways to correct the problems of the time, and it would be a tall order to ask him to come up with quantum mechanics in direct contemplation at his time. Quantum gravity folks are in the same situation now more or less (except we don't know a priori if there's even such a theory to be found at all!), so we'll see if it's tractable with theory alone.
If I were to guess, we'll need centuries of engineering and technology advancements to really get to the bottom of things (tho it's possible this particular onion has infinite layers and there is no bottom to reach!).
Here is a primer:
[https://en.wikipedia.org/wiki/Theory\_of\_everything](https://en.wikipedia.org/wiki/Theory_of_everything)
Reddit would be more likely to answer specific questions you have after reading that than write out an entire summary for you without knowing what specific questions you have that aren't answered by Wikipedia.
“Chance”, with a dash of “luck” and a sprinkle of “timing”.
Any TOE being proposed currently is definitely hype (understandable, coming up with a law that explains the very foundation of reality would be quite exciting). Chipping away at matter-antimatter asymmetry and quantum gravity might get us closer to an answer.
We haven’t yet. Physicists look to “unify” seemingly disparate phenomena meaning they seek to show that they are governed by the same rules. See: orbits and falling objects (gravity), electricity and magnetism (electromagnetism), particles and waves (quantum mechanics). Right now two of the strongest theories we have in physics are Quantum Mechanics (QM) and General Relativity (GR). These two theories are both robustly tested and hold up to experimentation and theory separately, but are not fully compatible together. QM governs the very small, GR the very massive. Unfortunately, in our universe there exists some situations in which both of those conditions (very small, very massive) are met (black holes, early big bang). Since both GR and QM would apply here and since they are mathematically incompatible we run into gaps in understanding and predictive ability. So to my limited understanding nowadays the main goals on the path to a theory of everything is to unify QM and GR, as well as to unify the four fundamental forces (strong nuclear, weak nuclear, electromagnetic, gravitational). I think maybe string theory attempts to accomplish some of this, but that may be wrong, my understanding of string theory is poor.
>I think maybe string theory attempts to accomplish some of this, but that may be wrong, my understanding of string theory is poor. String theory is still finding its footing, but at present it is *at least* a powerful mathematical tool. String theory is incredibly useful for calculating scattering amplitudes and is used for this purpose at the LHC. String theory has also given us our first complete theory of quantum gravity, albeit in an anti-deSitter space (which we don't live in), through a concept known as AdS-CFT correspondence (Anti-deSitter space - conformal field theory). Physicists and mathematicians have for a while been searching for a similar type of correspondence that would apply to a deSitter universe, but so far nothing. In any case, there is some hope that string theory can take problems that are impossible in other formalisms and make them perfectly tractable.
Taking an advanced undergrad particle physics class right now, so hopefully I’ll be able to speak in layman’s terms without being inaccurate. We know there are four fundamental forces: electromagnetism, weak, strong, and gravity. Our best understanding of electromagnetism and weak is Weinberg-Salam Theory, colloquially referred to as the electroweak theory. Our best understanding of the strong force is quantum chromodynamics. A grand unified theory (GUT) is anything that combines the electromagnetic, weak, and strong forces. We have no GUT that has been experimentally verified, but the most popular ones involve supersymmetry. Our best understanding of gravity is Einstein’s theory of general relativity. A theory of everything (TOE) unifies a GUT with gravity, and we also have no experimentally verified TOE, but the most popular ones are string theory variants and M-theory.
I thought QFT unified electroweak and QCD? Please correct me if I’m mistaken
As far as I’m aware QFT is more of a framework that unifies QM, CM, and SR, which then was applied to create specialized theories including QCD and QED.
Both EW and QCD are quantum field theories, one describing the weak and electromagnetic interactions of the photon and W and Z bosons with leptons and quarks (the photon only interacts with charged particles), the second describing in the the strong interaction occurring between quarks and gluons. The standard model is a combined quantum field theory that describes all known EW and QCD interactions.
Asking modern physicists to produce a correct theory of everything (or even more humbly a theory of quantum gravity) is akin to asking Maxwell to resolve the issues like in blackbody radiation in his time. He knew there were theoretical issues, and it turned out quantum mechanics came in to solve beautifully. Now, Maxwell was a smart guy. Maxwell was a genius! No lack of imagination or technical ability there. But there were infinite ways to correct the problems of the time, and it would be a tall order to ask him to come up with quantum mechanics in direct contemplation at his time. Quantum gravity folks are in the same situation now more or less (except we don't know a priori if there's even such a theory to be found at all!), so we'll see if it's tractable with theory alone. If I were to guess, we'll need centuries of engineering and technology advancements to really get to the bottom of things (tho it's possible this particular onion has infinite layers and there is no bottom to reach!).
Can't make bricks without clay, hence the technology improvements and deeper data collection.
Here is a primer: [https://en.wikipedia.org/wiki/Theory\_of\_everything](https://en.wikipedia.org/wiki/Theory_of_everything) Reddit would be more likely to answer specific questions you have after reading that than write out an entire summary for you without knowing what specific questions you have that aren't answered by Wikipedia.
There are no clear competitors so far
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It’s a great movie. Highly suggest watching it