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\newtheorem{prop}{Proposition} \newtheorem{cor}{Corollary} \newtheorem*{utheorem}{Theorem} \newtheorem*{ulemma}{Lemma} \newtheorem*{uprop}{Proposition} \newtheorem*{ucor}{Corollary} \theoremstyle{definition} \newtheorem{defn}{Definition} \newtheorem{example}{Example} \newtheorem*{udefn}{Definition} \newtheorem*{uexample}{Example} \theoremstyle{remark} \newtheorem{remark}{Remark} \newtheorem{note}{Note} \newtheorem*{uremark}{Remark} \newtheorem*{unote}{Note} %------------------------------------------------------------------- \begin{document} %------------------------------------------------------------------- \section*{E11} \hypertarget{context}{}\subsubsection*{{Context}}\label{context} \hypertarget{exceptional_structures}{}\paragraph*{{Exceptional structures}}\label{exceptional_structures} [[!include exceptional structures -- contents]] \hypertarget{group_theory}{}\paragraph*{{Group Theory}}\label{group_theory} [[!include group theory - contents]] \hypertarget{lie_theory}{}\paragraph*{{Lie theory}}\label{lie_theory} [[!include infinity-Lie theory - contents]] \hypertarget{contents}{}\section*{{Contents}}\label{contents} \noindent\hyperlink{idea}{Idea}\dotfill \pageref*{idea} \linebreak \noindent\hyperlink{properties}{Properties}\dotfill \pageref*{properties} \linebreak \noindent\hyperlink{as_uduality_group_of_0d_supergravity}{As U-duality group of 0d supergravity}\dotfill \pageref*{as_uduality_group_of_0d_supergravity} \linebreak \noindent\hyperlink{FundamentalRepresentationAndBraneCharges}{Fundamental representation and brane charges}\dotfill \pageref*{FundamentalRepresentationAndBraneCharges} \linebreak \noindent\hyperlink{references}{References}\dotfill \pageref*{references} \linebreak \noindent\hyperlink{general}{General}\dotfill \pageref*{general} \linebreak \noindent\hyperlink{ReferencesRelationToSupergravity}{Relation to supergravity}\dotfill \pageref*{ReferencesRelationToSupergravity} \linebreak \hypertarget{idea}{}\subsection*{{Idea}}\label{idea} A hyperbolic [[Kac-Moody Lie algebra]] in the E-series \ldots{} [[E6]], [[E7]], [[E8]], [[E9]], [[E10]], $E_{11}$, \ldots{} \hypertarget{properties}{}\subsection*{{Properties}}\label{properties} \hypertarget{as_uduality_group_of_0d_supergravity}{}\subsubsection*{{As U-duality group of 0d supergravity}}\label{as_uduality_group_of_0d_supergravity} $E_{11}$ is conjectured (\hyperlink{West01}{West 01}) to be the [[U-duality]] group (see there) of [[11-dimensional supergravity]] [[KK-compactification|compactified]] to 0 dimensions. [[!include U-duality -- table]] \hypertarget{FundamentalRepresentationAndBraneCharges}{}\subsubsection*{{Fundamental representation and brane charges}}\label{FundamentalRepresentationAndBraneCharges} The first [[fundamental representation]] of $E_{11}$, usually denoted $l_1$, is argued, since (\hyperlink{West04}{West 04}), to contain in its decomposition into [[representations]] of $GL(11)$ the representations in which the [[charges]] of the [[M-branes]] and other [[BPS states]] transform. According to (\hyperlink{NicolaiFischbacher03}{Nicolai-Fischbacher 03, first three rows of table 2 on p. 72}, \hyperlink{West04}{West 04}, \hyperlink{KleinschmidtWest04}{Kleinschmidt-West 04}) and concisely stated for instance in (\hyperlink{West11}{West 11, (2.17)}), the level decomposition of $l_1$ under $GL(11)$ starts out as so: \begin{displaymath} l_1 \simeq \underset{level\,0}{ \underbrace{ \mathbb{R}^{10,1} }} \oplus \underset{level\,1}{ \underbrace{ \wedge^2 (\mathbb{R}^{10,1})^\ast }} \oplus \underset{level\,2}{ \underbrace{ \wedge^5 (\mathbb{R}^{10,1})^\ast }} \oplus \underset{level\,3}{\underbrace{ \wedge^7 (\mathbb{R}^{10,1})^\ast \otimes_s (\mathbb{R}^{10,1})^\ast \oplus \wedge^8 (\mathbb{R}^{10,1})^\ast }} \oplus \cdots \end{displaymath} Here the $level \leq 2$-truncation happens to coincide with the bosonic [[body]] underlying the [[M-theory super Lie algebra]] and via the relation of that to [[BPS charges]] in [[11-dimensional supergravity]]/[[M-theory]], the [[direct sums|direct summands]] here have been argued to naturally correspond to \begin{itemize}% \item level 0: [[momentum]] \item level 1: [[M2-brane]] charge \item level 2: [[M5-brane]] charge \item level 3: [[dual graviton]] charge (\hyperlink{West11}{West 11, section N}) (has two components \footnote{private communication with [[Axel Kleinschmidt]]} ) \end{itemize} \hypertarget{references}{}\subsection*{{References}}\label{references} \hypertarget{general}{}\subsubsection*{{General}}\label{general} \begin{itemize}% \item [[Peter West]], section 16.7 of \emph{[[Introduction to Strings and Branes]]} \item [[Hermann Nicolai]], Thomas Fischbacher, \emph{Low Level Representations for E10 and E11} (\href{http://arxiv.org/abs/hep-th/0301017}{arXiv:hep-th/0301017}) \item H. Mkrtchyan, R. Mkrtchyan, \emph{$E_{11},K_{11}$ and $EE_{11}$} (\href{http://arxiv.org/abs/hep-th/0407148}{arXiv:hep-th/0407148}) \end{itemize} \hypertarget{ReferencesRelationToSupergravity}{}\subsubsection*{{Relation to supergravity}}\label{ReferencesRelationToSupergravity} Literature discussing $E_{11}$ [[U-duality]] and in the context of [[exceptional generalized geometry]] of [[11-dimensional supergravity]]. Review includes \begin{itemize}% \item [[Peter West]], section 17.5 of \emph{[[Introduction to Strings and Branes]]} \item [[Fabio Riccioni]], \emph{$E_{11}$ and M-theory}, talk at \href{http://www.ift.uam.es/strings07/}{Strings07} (\href{http://member.ipmu.jp/yuji.tachikawa/stringsmirrors/2007/riccioni.pdf}{pdf slides}) \item [[Fabio Riccioni]], [[Peter West]], \emph{The $E_{11}$ origin of all maximal supergravities}, JHEP 0707:063,2007 (\href{http://arxiv.org/abs/0705.0752}{arXiv:0705.0752}, \href{http://inspirehep.net/record/749966/}{spire}) \item [[Paul Cook]], \emph{Connections between Kac-Moody algebras and M-theory} PhD thesis (\href{http://arxiv.org/abs/0711.3498}{arXiv:0711.3498}) \item [[Peter West]], \emph{A brief review of E theory} (\href{http://arxiv.org/abs/1609.06863}{arXiv:1609.06863}) \end{itemize} Original articles include the following: The observation that $E_{11}$ seems to neatly organize the structures in [[11-dimensional supergravity]]/[[M-theory]] is due to \begin{itemize}% \item [[Peter West]], \emph{$E_{11}$ and M theory}, Class. Quant. Grav., 18:4443--4460, 2001. (\href{http://arxiv.org/abs/hep-th/0104081}{arXiv:hep-th/0104081}) \end{itemize} A precursor to (\hyperlink{West01}{West 01}) is \begin{itemize}% \item [[Bernard Julia]], \emph{Dualities in the classical supergravity limits} (\href{http://arxiv.org/abs/hep-th/9805083}{arXiv:hep-th/9805083}) \end{itemize} as explained in (\hyperlink{HenneauxJuliaLevie10}{Henneaux-Julia-Levie 10}). The derivation of the [[equations of motion]] of [[11-dimensional supergravity]] and maximally supersymmetric [[5d supergravity]] from a [[vielbein]] with values in the [[semidirect product]] $E_{11}$ with its [[fundamental representation]] is due to \begin{itemize}% \item [[Peter West]], \emph{Generalised geometry, eleven dimensions and $E_{11}$}, J. High Energ. Phys. (2012) 2012: 18 (\href{http://arxiv.org/abs/1111.1642}{arXiv:1111.1642}) \item Alexander G. Tumanov, [[Peter West]], \emph{$E_{11}$ must be a symmetry of strings and branes}, Physics Letters B Volume 759, 10 August 2016, Pages 663--671 (\href{https://arxiv.org/abs/1512.01644}{arXiv:1512.01644}) \item Alexander G. Tumanov, [[Peter West]], \emph{$E_{11}$ in $11d$}, Physics Letters B Volume 758, 10 July 2016, Pages 278--285 (\href{https://arxiv.org/abs/1601.03974}{arXiv:1601.03974}) \end{itemize} This way that elements of [[cosets]] of the [[semidirect product]] $E_{11}$ with its [[fundamental representation]] may encode [[equations of motion]] of [[11-dimensional supergravity]] follows previous considerations for [[Einstein equations]] in \begin{itemize}% \item [[Abdus Salam]], J. Strathdee, \emph{Nonlinear realizations. 1: The Role of Goldstone bosons, Phys. Rev. 184 (1969) 1750,} \item [[Chris Isham]], [[Abdus Salam]], J. Strathdee, \emph{Spontaneous, breakdown of conformal symmetry}, Phys. Lett. 31B (1970) 300. \item A. Borisov, V. Ogievetsky, \emph{Theory of dynamical affine and conformal symmetries as the theory of the gravitational field}, Theor. Math. Phys. 21 (1973) 1179-1188 (\href{http://www.mathnet.ru/php/archive.phtml?wshow=paper&jrnid=tmf&paperid=3902&option_lang=eng}{web}) \item V. Ogievetsky, \emph{Infinite-dimensional algebra of general covariance group as the closure of the finite dimensional algebras of conformal and linear groups}, Nuovo. Cimento, 8 (1973) 988. \end{itemize} Further developments of the proposed $E_{11}$ formulation of [[M-theory]] include \begin{itemize}% \item [[Peter West]], \emph{$E_{11}$, ten forms and supergravity}, JHEP0603:072,2006 (\href{http://arxiv.org/abs/hep-th/0511153}{arXiv:hep-th/0511153}) \item [[Fabio Riccioni]], [[Peter West]], \emph{Dual fields and $E_{11}$}, Phys.Lett.B645:286-292,2007 (\href{http://arxiv.org/abs/hep-th/0612001}{arXiv:hep-th/0612001}) \item [[Fabio Riccioni]], [[Peter West]], \emph{E(11)-extended spacetime and gauged supergravities}, JHEP 0802:039,2008 (\href{http://arxiv.org/abs/0712.1795}{arXiv:0712.1795}) \item [[Fabio Riccioni]], Duncan Steele, [[Peter West]], \emph{The E(11) origin of all maximal supergravities - the hierarchy of field-strengths}, JHEP 0909:095 (2009) (\href{http://arxiv.org/abs/0906.1177}{arXiv:0906.1177}) \item [[Eric Bergshoeff]], I. De Baetselier, T. Nutma, \emph{E(11) and the Embedding Tensor} (\href{http://arxiv.org/abs/0705.1304}{arXiv:0705.1304}, \href{http://mms.technologynetworks.net/posters/0364.pdf}{poster}) \item Guillaume Bossard, [[Axel Kleinschmidt]], Jakob Palmkvist, [[Christopher Pope]], [[Ergin Sezgin]], \emph{Beyond $E_{11}$} (\href{https://arxiv.org/abs/1703.01305}{arXiv:1703.01305}) \end{itemize} Discussion of the [[semidirect product]] of $E_{11}$ with its $l_1$-[[representation]], and arguments that the [[charges]] of the [[M-theory super Lie algebra]] and in fact further brane charges may be identified inside $l_1$ originate in \begin{itemize}% \item [[Peter West]], \emph{$E_{11}$, $SL(32)$ and Central Charges}, Phys.Lett.B575:333- 342,2003 (\href{http://arxiv.org/abs/hep-th/0307098}{arXiv:hep-th/0307098}) \end{itemize} and was further explored in \begin{itemize}% \item [[Axel Kleinschmidt]], [[Peter West]], \emph{Representations of $G^{+++}$ and the role of space-time}, JHEP 0402 (2004) 033 (\href{http://arxiv.org/abs/hep-th/0312247}{arXiv:hep-th/0312247}) \item [[Paul Cook]], [[Peter West]], \emph{Charge multiplets and masses for $E(11)$}, JHEP 11 (2008) 091 (\href{http://arxiv.org/abs/0805.4451}{arXiv:0805.4451}) \item [[Peter West]], \emph{$E_{11}$ origin of Brane charges and U-duality multiplets}, JHEP 0408 (2004) 052 (\href{http://arxiv.org/abs/hep-th/0406150}{arXiv:hep-th/0406150}) \end{itemize} Relation to [[exceptional field theory]] is discussed in \begin{itemize}% \item Alexander G. Tumanov, [[Peter West]], \emph{$E_{11}$ and exceptional field theory} (\href{http://arxiv.org/abs/1507.08912}{arXiv:1507.08912}) \end{itemize} Relation to [[Borcherds superalgebras]] is discussed in \begin{itemize}% \item Pierre Henry-Labordere, [[Bernard Julia]], Louis Paulot, \emph{Borcherds symmetries in M-theory}, JHEP 0204 (2002) 049 (\href{http://arxiv.org/abs/hep-th/0203070}{arXiv:hep-th/0203070}) \item [[Marc Henneaux]], [[Bernard Julia]], J\'e{}r\^o{}me Levie, \emph{$E_{11}$, Borcherds algebras and maximal supergravity} (\href{http://arxiv.org/abs/1007.5241}{arxiv:1007.5241}) \item Jakob Palmkvist, \emph{Tensor hierarchies, Borcherds algebras and $E_{11}$}, JHEP 1202 (2012) 066 (\href{http://arxiv.org/abs/1110.4892}{arXiv:1110.4892}) \end{itemize} \end{document}