String Theory | ||
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All Roads Lead to String Theory (Polchinski) | ||
Prior to the First Superstring Revolution
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Early History | S-Matrix Theory Regge Trajectory | |
Bosonic String Theory | Worldsheet String Bosonic String Theory String Perturbation Theory Tachyon Condensation | |
Supersymmetric Revolution | Supersymmetry RNS Formalism GS Formalism BPS | |
Superstring Revolutions
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First Superstring Revolution | GSO Projection Type II String Theory Type IIB String Theory Type IIA String Theory Type I String Theory Type H String Theory Type HO String Theory Type HE String Theory |
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Second Superstring Revolution | T-Duality D-Brane S-Duality Horava-Witten String Theory M-Theory Holographic Principle N=4 Super-Yang-Mills Theory AdS CFT BFSS Matrix Theory Matrix String Theory (2,0) Theory Twistor String Theory F-Theory String Field Theory Pure Spinor Formalism |
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After the Revolutions
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Phenomenology | String Theory Landscape Minimal Supersymmetric Standard Model String Phenomenology | |
This article or section 's content is very similar or exactly the same as that at Wikipedia. This is because the contributor of this article had initially contributed it to wikipedia. |
In String Theory, a Worldsheet is a two-dimensional manifold which describes the embedding of a string in spacetime.
[1]
The term was coined by Leonard Susskind around 1967 as a direct generalization of the Worldline concept for a point particle in Special and General Relativity.
The type of String, the geometry of the spacetime in which it propagates, and the presence of long-range background fields (such as Gauge Fields and the Spacetime Metric) are encoded in a Conformal Field Theory defined on the worldsheet. [2] For example, the Bosonic String in 26-dimensional Minkowski spacetime has a worldsheet conformal field theory consisting of 26 free scalar fields. Meanwhile, a superstring worldsheet theory in 10 dimensions consists of 10 free scalar fields and their fermionic superpartners.
A String Theory can be almost entirely formulated in terms of a Lagrangian Density across a worldsheet.
In Bosonic String Theory, the Lagrangian Density across the worldsheet is given by the Polyakov Lagrangian Density. [3]
In Type IIB String Theory, Type IIA String Theory and Type I String Theory, the Lagrangian Density across the worldsheet is the Ramond Neveu-Schwarz Lagrangian Density.[3]
In the Type HE String Theory and the Type HO String Theory is given by the Hetrotic Lagrangian Density.[3]
References[]
- ↑ Kaku, Michio (2000). Strings, Conformal Fields, and M-Theory:. New York: Springer. pp. 3–32. ISBN 978-0387988924. http://www.amazon.com/Strings-Conformal-M-Theory-Graduate-Contemporary/dp/0387988920/ref=sr_1_1?s=books&ie=UTF8&qid=1371008020&sr=1-1&keywords=Strings%2C+Conformal+Fields%2C+and+M-Theory.
- ↑ Wray, Kevin. An Introduction to String theory. http://math.berkeley.edu/~kwray/papers/string_theory.pdf.
- ↑ 3.0 3.1 3.2 McMohan, David (2009). String theory DeMystified. Chicago: McGrawHill. ISBN 978-0071498708. http://www.nucleares.unam.mx/~alberto/apuntes/mcmahon.pdf.