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2 | | - "cell_id" : 14643089922803689914, |
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12 | | - "cell_id" : 18043264383205729330, |
| 12 | + "cell_id" : 6179245722104386386, |
13 | 13 | "cell_origin" : "client", |
14 | 14 | "cell_type" : "latex_view", |
15 | | - "source" : "\\part*{Cartan structural equations and Bianchi identity}\n\n\\author{Oscar Castillo-Felisola}\n\n\\section*{Theoretical background}\n\nLet $M$ be a manifold, and $g$ a (semi)Riemannian metric defined on $M$. Then the line element for the metric $g$ is\n\\begin{equation*}\n \\mathrm{d}{s}^2(g) = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu.\n\\end{equation*}\nNonetheless, the information about the metric structure of the manifold can be translated to the language of frames,\n\\begin{equation*}\n \\begin{split}\n \\mathrm{d}{s}^2(g)\n & = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; e^{a}_{\\mu}(x) \\, e^{b}_{\\nu}(x) \\; \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; \\mathrm{e}^{a} \\otimes \\mathrm{e}^{b}.\n \\end{split}\n\\end{equation*}\nTherefore, the vielbein 1-form, $\\mathrm{e}^{a} \\equiv e^{a}_{\\mu}(x) \\mathrm{d}{x}^\\mu$, encodes the information of the metric tensor.\nIn order to complete the structure, one needs information about the transport of geometrical objects lying on bundles\nbased on $M$. That information is encoded on the spin connection 1-form, $\\omega^{a}{}_{b}$. Using these quantities one finds\nthe generalisation of the structure equations of Cartan,\n\\begin{align}\n \\mathrm{d}{\\mathrm{e}^{a}} + \\omega^{a}{}_{b} \\wedge \\mathrm{e}^{b} & = \\mathrm{T}^{a},\n \\label{firstSE}\\\\\n \\mathrm{d}{\\omega^{a}{}_{c}} + \\omega^{a}{}_{b} \\wedge \\omega^{b}{}_{c} & = \\mathrm{R}^{a}{}_{c}\n \\label{secondSE}.\n\\end{align}\nThe torsion 2-form, $\\mathrm{T}^{a}$, and the curvature 2-form, $\\mathrm{R}^{a}{}_{c}$, measure the impossibility of endowing $M$ with\nan Euclidean structure.\n\n\\section*{Manipulation of the structural equations}\n\n\\subsection*{Definitions}" |
| 15 | + "source" : "\\section*{Cartan structural equations and Bianchi identity}\n\n\\author{Oscar Castillo-Felisola}\n\n\\section*{Theoretical background}\n\nLet $M$ be a manifold, and $g$ a (semi)Riemannian metric defined on $M$. Then the line element for the metric $g$ is\n\\begin{equation*}\n \\mathrm{d}{s}^2(g) = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu.\n\\end{equation*}\nNonetheless, the information about the metric structure of the manifold can be translated to the language of frames,\n\\begin{equation*}\n \\begin{split}\n \\mathrm{d}{s}^2(g)\n & = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; e^{a}_{\\mu}(x) \\, e^{b}_{\\nu}(x) \\; \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; \\mathrm{e}^{a} \\otimes \\mathrm{e}^{b}.\n \\end{split}\n\\end{equation*}\nTherefore, the vielbein 1-form, $\\mathrm{e}^{a} \\equiv e^{a}_{\\mu}(x) \\mathrm{d}{x}^\\mu$, encodes the information of the metric tensor.\nIn order to complete the structure, one needs information about the transport of geometrical objects lying on bundles\nbased on $M$. That information is encoded on the spin connection 1-form, $\\omega^{a}{}_{b}$. Using these quantities one finds\nthe generalisation of the structure equations of Cartan,\n\\begin{align}\n \\mathrm{d}{\\mathrm{e}^{a}} + \\omega^{a}{}_{b} \\wedge \\mathrm{e}^{b} & = \\mathrm{T}^{a},\n \\label{firstSE}\\\\\n \\mathrm{d}{\\omega^{a}{}_{c}} + \\omega^{a}{}_{b} \\wedge \\omega^{b}{}_{c} & = \\mathrm{R}^{a}{}_{c}\n \\label{secondSE}.\n\\end{align}\nThe torsion 2-form, $\\mathrm{T}^{a}$, and the curvature 2-form, $\\mathrm{R}^{a}{}_{c}$, measure the impossibility of endowing $M$ with\nan Euclidean structure.\n\n\\section*{Manipulation of the structural equations}\n\n\\subsection*{Definitions}" |
16 | 16 | } |
17 | 17 | ], |
18 | 18 | "hidden" : true, |
19 | | - "source" : "\\part*{Cartan structural equations and Bianchi identity}\n\n\\author{Oscar Castillo-Felisola}\n\n\\section*{Theoretical background}\n\nLet $M$ be a manifold, and $g$ a (semi)Riemannian metric defined on $M$. Then the line element for the metric $g$ is\n\\begin{equation*}\n \\mathrm{d}{s}^2(g) = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu.\n\\end{equation*}\nNonetheless, the information about the metric structure of the manifold can be translated to the language of frames,\n\\begin{equation*}\n \\begin{split}\n \\mathrm{d}{s}^2(g)\n & = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; e^{a}_{\\mu}(x) \\, e^{b}_{\\nu}(x) \\; \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; \\mathrm{e}^{a} \\otimes \\mathrm{e}^{b}.\n \\end{split}\n\\end{equation*}\nTherefore, the vielbein 1-form, $\\mathrm{e}^{a} \\equiv e^{a}_{\\mu}(x) \\mathrm{d}{x}^\\mu$, encodes the information of the metric tensor.\nIn order to complete the structure, one needs information about the transport of geometrical objects lying on bundles\nbased on $M$. That information is encoded on the spin connection 1-form, $\\omega^{a}{}_{b}$. Using these quantities one finds\nthe generalisation of the structure equations of Cartan,\n\\begin{align}\n \\mathrm{d}{\\mathrm{e}^{a}} + \\omega^{a}{}_{b} \\wedge \\mathrm{e}^{b} & = \\mathrm{T}^{a},\n \\label{firstSE}\\\\\n \\mathrm{d}{\\omega^{a}{}_{c}} + \\omega^{a}{}_{b} \\wedge \\omega^{b}{}_{c} & = \\mathrm{R}^{a}{}_{c}\n \\label{secondSE}.\n\\end{align}\nThe torsion 2-form, $\\mathrm{T}^{a}$, and the curvature 2-form, $\\mathrm{R}^{a}{}_{c}$, measure the impossibility of endowing $M$ with\nan Euclidean structure.\n\n\\section*{Manipulation of the structural equations}\n\n\\subsection*{Definitions}" |
| 19 | + "source" : "\\section*{Cartan structural equations and Bianchi identity}\n\n\\author{Oscar Castillo-Felisola}\n\n\\section*{Theoretical background}\n\nLet $M$ be a manifold, and $g$ a (semi)Riemannian metric defined on $M$. Then the line element for the metric $g$ is\n\\begin{equation*}\n \\mathrm{d}{s}^2(g) = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu.\n\\end{equation*}\nNonetheless, the information about the metric structure of the manifold can be translated to the language of frames,\n\\begin{equation*}\n \\begin{split}\n \\mathrm{d}{s}^2(g)\n & = g_{\\mu\\nu} \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; e^{a}_{\\mu}(x) \\, e^{b}_{\\nu}(x) \\; \\mathrm{d}{x}^\\mu \\otimes \\mathrm{d}{x}^\\nu \\\\\n & = \\eta_{ab} \\; \\mathrm{e}^{a} \\otimes \\mathrm{e}^{b}.\n \\end{split}\n\\end{equation*}\nTherefore, the vielbein 1-form, $\\mathrm{e}^{a} \\equiv e^{a}_{\\mu}(x) \\mathrm{d}{x}^\\mu$, encodes the information of the metric tensor.\nIn order to complete the structure, one needs information about the transport of geometrical objects lying on bundles\nbased on $M$. That information is encoded on the spin connection 1-form, $\\omega^{a}{}_{b}$. Using these quantities one finds\nthe generalisation of the structure equations of Cartan,\n\\begin{align}\n \\mathrm{d}{\\mathrm{e}^{a}} + \\omega^{a}{}_{b} \\wedge \\mathrm{e}^{b} & = \\mathrm{T}^{a},\n \\label{firstSE}\\\\\n \\mathrm{d}{\\omega^{a}{}_{c}} + \\omega^{a}{}_{b} \\wedge \\omega^{b}{}_{c} & = \\mathrm{R}^{a}{}_{c}\n \\label{secondSE}.\n\\end{align}\nThe torsion 2-form, $\\mathrm{T}^{a}$, and the curvature 2-form, $\\mathrm{R}^{a}{}_{c}$, measure the impossibility of endowing $M$ with\nan Euclidean structure.\n\n\\section*{Manipulation of the structural equations}\n\n\\subsection*{Definitions}" |
20 | 20 | }, |
21 | 21 | { |
22 | 22 | "cell_id" : 13528271774984453456, |
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