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The '''Theory of Geometric Unity''' is an attempt by Eric Weinstein to produce a unified field theory by recovering the different, seemingly incompatible geometries of fundamental physics from a general structure with minimal assumptions. This structure is a mapping from a manifold \(X^4\) to a manifold \(Y\) called the [[Observerse|observerse]], which replaces Einstein's spacetime. The observerse can be constructed in four different ways, each generating a possible Geometric Unity theory. For the latest updates on the theory, visit '''[https://geometricunity.org/ geometricunity.org]'''.
The '''Theory of Geometric Unity''' is an attempt by Eric Weinstein to produce a unified field theory by recovering the different, seemingly incompatible geometries of fundamental physics from a general structure with minimal assumptions. This structure is a mapping from a manifold <math>X^4</math> to a manifold <math>Y</math> called the [[Observerse|observerse]], which replaces Einstein's spacetime. For the latest updates on the theory, visit '''https://geometricunity.org/'''.


This page currently summarizes information surrounding the theory. After the manuscript is released, it will be developed with more technical information.
This page currently summarizes information surrounding the theory.


__TOC__
__TOC__
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== Reframing the Central Question of Physics ==
Riemannian and Ehresmannian. Each simplest in their category. Don't quantize gravity, unite the geometries.


== Concepts ==
=== Observerse ===
The '''observerse''' is the central mathematical object in the [[Theory of Geometric Unity]]. It is a mapping from a four-dimensional manifold <math>X^4</math> to a manifold <math>Y</math>, which replaces Einstein's spacetime. There are four different constructions of the observerse: exogenous, bundle-theoretic, endogenous, and tautological. Each generates a possible Geometric Unity theory.
Read more at [[Observerse|observerse]].
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== Motivations ==
== Motivations ==
Eric has discussed many topics in relation to Geometric Unity.
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=== Beauty ===
=== Beauty ===
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=== Source Code and the End of Physics ===
=== Source Code and the End of Physics ===
In his answer to the last [https://www.edge.org/ Edge.org] annual question "What is the Last Question?", [https://www.edge.org/response-detail/27761 Eric responded:]
In his answer to the last [https://www.edge.org/ Edge.org] annual question "What is the Last Question?", Eric [https://www.edge.org/response-detail/27761 responded:]
<blockquote style="font-size: 125%; background: #f3f3ff; border-color: #ddd;">
<blockquote style="font-size: 125%; background: #f3f3ff; border-color: #ddd;">
Does something unprecedented happen when we finally learn our own source code?
Does something unprecedented happen when we finally learn our own source code?
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The source code, or a theory of everything, would mean the end of theoretical discovery at the most fundamental level of physics; all new discovery would take place at levels of more complexity.
The source code, or a theory of everything, would mean the end of theoretical discovery at the most fundamental level of physics; all new discovery would take place at levels of more complexity.


==== Twin Nuclei Problem of Cell and Atom ====
=== Twin Nuclei Problem of Cell and Atom ===
Geometric Unity is hoped to solve the [[Twin Nuclei Problem]] by finding a means of breaking the Einsteinian speed limit, the speed of light, so that human life can spread across the cosmos. Eric says that does not necessarily imply faster-than-light travel or other concepts in that vein, and that he does not know whether this hope will bear fruit. A theory of everything, though, would provide definite means of exploring possible ways around Einstein's constraint.
Geometric Unity is hoped to solve the [[Twin Nuclei Problem]] by finding a means of breaking the Einsteinian speed limit, the speed of light, so that human life can spread across the cosmos. Eric says that does not necessarily imply faster-than-light travel or other concepts in that vein, and that he does not know whether this hope will bear fruit. A theory of everything, though, would provide definite means of exploring possible ways around Einstein's constraint.


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=== 2013 First Presentation ===
=== 2013 First Presentation ===
[[File:Oxford Lecture Cover Image.jpg|thumb|right]]
[[File:Oxford Lecture Cover Image.jpg|thumb|right]]
Geometric Unity was [[A Portal Special Presentation- Geometric Unity: A First Look|first presented]] in three Simonyi Special Lectures delivered over the course of a week at the University of Oxford. The lectures were organized by Marcus du Sautoy, the Simonyi Professor for the Public Understanding of Science. The lectures provided a broad overview of the mathematical structures in the theory’s endogenous version, discussed where current effective theories are recovered in those structures, and showed general predictions based on those structures.
Geometric Unity was [[A Portal Special Presentation- Geometric Unity: A First Look|first presented]] in three Simonyi Special Lectures delivered over the course of a week at the University of Oxford. The lectures were organized by [https://twitter.com/MarcusduSautoy Marcus du Sautoy], the Simonyi Professor for the Public Understanding of Science. The lectures provided a broad overview of the mathematical structures in the theory’s endogenous version, discussed where current effective theories are recovered in those structures, and showed general predictions based on those structures.


=== 2016 Private Talk at FQXi ===
=== 2016 Private Talk at FQXi ===
Three years after the first presentation at Oxford, Eric gave a private talk on Geometric Unity at [https://fqxi.org/ FQXi].
Three years after the first presentation at Oxford, Eric gave a private talk on Geometric Unity at [https://fqxi.org/ FQXi.]


{{#widget:Tweet|id=767530817203478528}}
{{#widget:Tweet|id=767530817203478528}}
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=== Problem Nr. 1: Einstein's Theory of General Relativity is not a proper Gauge Theory ===
=== Problem Nr. 1: Einstein's Theory of General Relativity is not a proper Gauge Theory ===


* From Einstein's general relativity, we take the Einstein projection of the curvature tensor of the Levi-Civita connection $$\nabla$$ of the metric $$P_E(F_{\nabla})$$
* From Einstein's general relativity, we take the Einstein projection of the curvature tensor of the Levi-Civita connection <math>\nabla</math> of the metric <math>P_E(F_{\nabla})</math>
* From Yang-Mills-Maxwell-Anderson-Higgs theory of gauge fields, we take the adjoint exterior derivative coupled to a connection $$d^\star_A F_A$$
* From Yang-Mills-Maxwell-Anderson-Higgs theory of gauge fields, we take the adjoint exterior derivative coupled to a connection <math>d^\star_A F_A</math>


'''Idea:''' What if the $$F$$'s are the same in both contexts?
'''Idea:''' What if the <math>F</math>'s are the same in both contexts?


Further, supposing these $$F$$'s are the same, then why apply two different operators?  
Further, supposing these <math>F</math>'s are the same, then why apply two different operators?  


'''Thus the question becomes:''' Is there any opportunity to combine these two operators?
'''Thus the question becomes:''' Is there any opportunity to combine these two operators?


A problem is that the hallmark of the Yang-Mills theory is the freedom to choose the data, the internal quantum numbers that give all the particles their personalities beyond the mass and the spin. We can allow the gauge group of symmetries to act on both sides of the equation, but the key problem is that: $$P_E(F_{\nabla h}) \neq  h^{-1} P_E(F_{\nabla}) h $$. If we act on connections on the right and then take the Einstein projection, this is not equal to first taking the projection and then conjugating with the gauge action. The gauge rotation is only acting on one of the two factors. Yet the projection is making use of both of them. So there is a fundamental incompatibility in the claim that Einstein's theory is a gauge theory relies more on analogy than an exact mapping between the two theories.
A problem is that the hallmark of the Yang-Mills theory is the freedom to choose the data, the internal quantum numbers that give all the particles their personalities beyond the mass and the spin. We can allow the gauge group of symmetries to act on both sides of the equation, but the key problem is that: <math>P_E(F_{\nabla h}) \neq  h^{-1} P_E(F_{\nabla}) h </math>. If we act on connections on the right and then take the Einstein projection, this is not equal to first taking the projection and then conjugating with the gauge action. The gauge rotation is only acting on one of the two factors. Yet the projection is making use of both of them. So there is a fundamental incompatibility in the claim that Einstein's theory is a gauge theory relies more on analogy than an exact mapping between the two theories.


=== Problem Nr. 2: Spinors are sensitive to the metric ===
=== Problem Nr. 2: Spinors are sensitive to the metric ===
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<blockquote>
<blockquote>
"So if we're going to take the spin-2 $$G_{\mu\nu}$$ field to be quantum mechanical, if it blinks out and does whatever the quantum does between observations. In the case of the photon, it is saying that the waves may blink out, but the ocean need not blink out. In the case of the Dirac theory, it is the ocean, the medium, in which the waves live that becomes uncertain itself. So even if you're comfortable with the quantum, to me, this becomes a bridge too far. So the question is: "How do we liberate the definition?"
"So if we're going to take the spin-2 <math>G_{\mu\nu}</math> field to be quantum mechanical, if it blinks out and does whatever the quantum does between observations. In the case of the photon, it is saying that the waves may blink out, but the ocean need not blink out. In the case of the Dirac theory, it is the ocean, the medium, in which the waves live that becomes uncertain itself. So even if you're comfortable with the quantum, to me, this becomes a bridge too far. So the question is: "How do we liberate the definition?"
How do we get the metric out from its responsibilities? It's been assigned far too many responsibilities. It is responsible for a volume form; for differential operators; it's responsible for measurement; it's responsible for being a dynamical field, part of the field content of the system."
How do we get the metric out from its responsibilities? It's been assigned far too many responsibilities. It is responsible for a volume form; for differential operators; it's responsible for measurement; it's responsible for being a dynamical field, part of the field content of the system."
</blockquote>
</blockquote>