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Lie Groups are Groups that are additionally smooth manifolds such that the multiplication and the inverse maps are smooth.

1 vote

motion group of projective octave level

I also don't know what "projective octave level" means but judging by the names of the groups and their dimensions, here is my guess: elliptic motion group - real compact group $F_4$ hyperbolic motion …
Vít Tuček's user avatar
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2 votes
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Rational homogenous spaces and symmetric spaces

Compact Riemannian symmetric spaces admitting a Lie group of diffeomorphisms $G$ properly containing the isometry group are essentialy (up to covers) the symmetric $R$-spaces, which are of the form $G …
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2 votes
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The quotient of a Lie group by the Levi factor of a parabolic subgroup

Exhausting account on homogeneous spaces of the form $G/P$ with $G$ semisimple and $P$ parabolic is given in this book. The relationship between $P$ and $L$ is also explained there in detail so presum …
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1 vote
0 answers
66 views

topologies on globalizations

I am reading notes by David Vogan on Unitary representations and Complex analysis (pdf / dvi). The setting is as follows (page 23): Let $X$ be a $(\mathfrak{g},K)$-module and let $X(\mu)$ denote its …
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2 votes

Universal property of induced representation

Your question can be rephrased as "When is the induction the same as coinduction?" This has appeared on MathOverflow before and fancy answer to your question can be found here: When are induction and …
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5 votes
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The "canonical fibration" for the Lie group $G_2$

In Spinors and Calibrations by F. Reese Harvey, you can find proof (p. 283) of $S^7 \simeq Spin(7)/G_2.$ It takes the same approach as Bryant's notes mentioned in the comments but it is much more deta …
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4 votes
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Invariant regular cones in Lie group representation

Regarding your second question, the cases where $C_{min} = C_{max}$ for cases where $G$ is a real form a complex semisimple Lie group have been classified by Misyureva. Basically, you get that $V$ is …
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8 votes
0 answers
118 views

Invariant complex structures for simple Lie groups

For which simple Lie groups there exists a left-invariant complex structure?
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2 votes

Matrix expression for elements of $\text{SO}_0(1,4)$

Yes, there should be an explicit expression. Let me sketch how to get it. Start with the Iwasawa decomposition to write your matrix $M$ as a product of three matrices $M = KAN$ where $N$ is nilpotent, …
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1 vote

Invariant subbundles of tangent bundle of flag variety

This is not an answer. Just a few well known facts. Each $P$-invariant subset is also invariant with respect to the Levi part $L$ of $P$ and hence it decomposes into irreducibles for $L$. The repres …
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4 votes
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Generalization of Killing form

According to theorem 2.15, all Cartan subalgebras of a complex semi-simple Lie algebras are conjugated. I.e. there exists $\alpha \in \mathrm{Inn}(\mathfrak{g})$ such that $\mathfrak{h}_1 = \alpha(\ma …
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3 votes

Peter-Weyl theorem as proven in Cartier's Primer

More generally, if $A$ is a bounded $G$-invariant operator acting on a unitary representation $(\rho,\mathcal{H})$ of $G$ and $A^*$ is it's adjoint (i.e. $(Ax,y) = (x,A^*y)$ for all $x,y\in \mathcal{H …
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1 vote

About the definition of E8, and Rosenfeld's "Geometry of Lie groups"

There seems to be a construction of $\mathfrak{e}_8$ using some sort of geometrical objects in Configurations of lines and models of Lie algebras by Laurent Manivel.
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1 vote

Fundamental representations and weight space dimension

Such representations are actually quite rare and are superset of the minuscule representations.
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2 votes

Is there an analogue of spin/oscillator representation for the general linear Lie algebra?

The Clifford / Weyl algebra duality stems from the symmetric / antisymmetric duality. For me the most natural way to generalize this to $GL(V)$ is kind of vacuous, i.e. the full tensor algebra $\bigot …
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