Lie bracket of vector fields in Penrose's abstract index notationWhich tensor fields on a symplectic manifold are invariant under all Hamiltonian vector fields?Lie group actions and f-relatednessIs there much theory of superalgebras acting on manifolds by alternating polyvector fields?Lie bracket of Invariant Vector fields Splitting of the double tangent bundle into vertical and horizontal parts, and defining partial derivativesNormalized Hamiltonian holomorphic vector fields on Sasakian manifoldsDoes for every vector field there always exist a volume form for which the vector field is a homothety?Properties of connection Laplacian on vector fieldsFunctoriality of the formality quasi-isomorphism of E-polydifferential operatorsNotation and geometry facts in a paper on the Diederich-Fornæss index
Lie bracket of vector fields in Penrose's abstract index notation
Which tensor fields on a symplectic manifold are invariant under all Hamiltonian vector fields?Lie group actions and f-relatednessIs there much theory of superalgebras acting on manifolds by alternating polyvector fields?Lie bracket of Invariant Vector fields Splitting of the double tangent bundle into vertical and horizontal parts, and defining partial derivativesNormalized Hamiltonian holomorphic vector fields on Sasakian manifoldsDoes for every vector field there always exist a volume form for which the vector field is a homothety?Properties of connection Laplacian on vector fieldsFunctoriality of the formality quasi-isomorphism of E-polydifferential operatorsNotation and geometry facts in a paper on the Diederich-Fornæss index
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In the abstract index notation of Penrose, indicies serve as placeholders to indicate the type of a tensor field. For example, $X^i$ denotes a vector field. What is the commonly accepted notation for the Lie bracket of two vector fields $X^i$ and $Y^j$?
Clearly, $[X^i, Y^j]^k$ does not work, because this would denote a $3$-contravariant tensor. Something like $[ cdot, cdot]_ij^ k X^i Y^j$ would work but looks strange.
dg.differential-geometry
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In the abstract index notation of Penrose, indicies serve as placeholders to indicate the type of a tensor field. For example, $X^i$ denotes a vector field. What is the commonly accepted notation for the Lie bracket of two vector fields $X^i$ and $Y^j$?
Clearly, $[X^i, Y^j]^k$ does not work, because this would denote a $3$-contravariant tensor. Something like $[ cdot, cdot]_ij^ k X^i Y^j$ would work but looks strange.
dg.differential-geometry
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In the abstract index notation of Penrose, indicies serve as placeholders to indicate the type of a tensor field. For example, $X^i$ denotes a vector field. What is the commonly accepted notation for the Lie bracket of two vector fields $X^i$ and $Y^j$?
Clearly, $[X^i, Y^j]^k$ does not work, because this would denote a $3$-contravariant tensor. Something like $[ cdot, cdot]_ij^ k X^i Y^j$ would work but looks strange.
dg.differential-geometry
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In the abstract index notation of Penrose, indicies serve as placeholders to indicate the type of a tensor field. For example, $X^i$ denotes a vector field. What is the commonly accepted notation for the Lie bracket of two vector fields $X^i$ and $Y^j$?
Clearly, $[X^i, Y^j]^k$ does not work, because this would denote a $3$-contravariant tensor. Something like $[ cdot, cdot]_ij^ k X^i Y^j$ would work but looks strange.
dg.differential-geometry
dg.differential-geometry
asked 11 hours ago
Tobias DiezTobias Diez
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2 Answers
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Penrose-Rindler write it $X^inabla_iY^j-Y^inabla_iX^j$.
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I think it is standard in the mathematical physics literature to write this as $[X,Y]^k$. The entire expression "$[X,Y]$" is a new vector and $k$ is its index.
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2 Answers
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$begingroup$
Penrose-Rindler write it $X^inabla_iY^j-Y^inabla_iX^j$.
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add a comment |
$begingroup$
Penrose-Rindler write it $X^inabla_iY^j-Y^inabla_iX^j$.
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add a comment |
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Penrose-Rindler write it $X^inabla_iY^j-Y^inabla_iX^j$.
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Penrose-Rindler write it $X^inabla_iY^j-Y^inabla_iX^j$.
answered 10 hours ago
Francois ZieglerFrancois Ziegler
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I think it is standard in the mathematical physics literature to write this as $[X,Y]^k$. The entire expression "$[X,Y]$" is a new vector and $k$ is its index.
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add a comment |
$begingroup$
I think it is standard in the mathematical physics literature to write this as $[X,Y]^k$. The entire expression "$[X,Y]$" is a new vector and $k$ is its index.
$endgroup$
add a comment |
$begingroup$
I think it is standard in the mathematical physics literature to write this as $[X,Y]^k$. The entire expression "$[X,Y]$" is a new vector and $k$ is its index.
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I think it is standard in the mathematical physics literature to write this as $[X,Y]^k$. The entire expression "$[X,Y]$" is a new vector and $k$ is its index.
answered 9 hours ago
WillRWillR
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