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KJW Mathematics

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[math]\begin{pmatrix} a & b & c \\ d & e & f \\ g & h & i \end{pmatrix}[/math]

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[math]|\Phi\!\!>\ ^{\underrightarrow{|\psi_1>}}\ \ |\phi_1\!\!>[/math]

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test

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[math]\text{mathbb: } \mathbb{the\ quick\ brown\ fox\ jumped\ over\ the\ lazy\ dog}[/math]

[math]\text{mathrm: } \mathrm{the\ quick\ brown\ fox\ jumped\ over\ the\ lazy\ dog}[/math]

[math]\text{mathcal: } \mathcal{the\ quick\ brown\ fox\ jumped\ over\ the\ lazy\ dog}[/math]

[math]\text{mathfrak: } \mathfrak{the\ quick\ brown\ fox\ jumped\ over\ the\ lazy\ dog}[/math]

[math]\text{mathscr: } \mathscr{the\ quick\ brown\ fox\ jumped\ over\ the\ lazy\ dog}[/math]

[math]\text{mathbb: } \mathbb{THE\ QUICK\ BROWN\ FOX\ JUMPED\ OVER\ THE\ LAZY\ DOG}[/math]

[math]\text{mathrm: } \mathrm{THE\ QUICK\ BROWN\ FOX\ JUMPED\ OVER\ THE\ LAZY\ DOG}[/math]

[math]\text{mathcal: } \mathcal{THE\ QUICK\ BROWN\ FOX\ JUMPED\ OVER\ THE\ LAZY\ DOG}[/math]

[math]\text{mathfrak: } \mathfrak{THE\ QUICK\ BROWN\ FOX\ JUMPED\ OVER\ THE\ LAZY\ DOG}[/math]

[math]\text{mathscr: } \mathscr{THE\ QUICK\ BROWN\ FOX\ JUMPED\ OVER\ THE\ LAZY\ DOG}[/math]

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test before

Spoiler Alert!

test box

test after

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[math]\mathfrak{e}^{\alpha_1 ... \alpha_n} = \mathfrak{e}_{\alpha_1 ... \alpha_n} = \left\{\begin{array}{cl} 1 & \text{if}\ \ \alpha_1 ... \alpha_n\ \ \text{is an EVEN permutation of}\ \ 1 ... n\\-1 & \text{if}\ \ \alpha_1 ... \alpha_n\ \ \text{is an ODD permutation of}\ \ 1 ... n\\0 & \text{if}\ \ \alpha_1 ... \alpha_n\ \ \text{is NOT a permutation of}\ \ 1 ... n\end{array}\right.[/math]

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[math]x \overline{x} x[/math]

[math]x \underline{x} x[/math]

[math]x \buildrel \rm abc \over {xyz} x[/math]

[math]x \buildrel \rm {abc} \over {xyz} x[/math]

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[math]{\partial^2 x \over \partial t^2}[/math]

[math]\displaystyle {\partial^2 x \over \partial t^2}[/math]

[math] \dfrac{\partial^2 x}{\partial t^2}[/math]

[math] \frac{\partial^2 x}{\partial t^2}[/math]

[math]\displaystyle \frac{\partial^2 x}{\partial t^2}[/math]

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[math]\dfrac{\partial \star}{\partial \overline{x}^{\mu}}[/math]

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[math]R{}_{p}^{\mskip{0.05 cm}·}{}_{t}^{\mskip{0.05 cm}·}{}_{p}^{\mskip{0.05 cm}·}{}^{p}_{\mskip{0.05 cm}·}{}^{t}_{\mskip{0.05 cm}·}{}_{p}^{\mskip{0.05 cm}·}{}_{p}^{\mskip{0.05 cm}·}[/math]

[math]R{}_l{}_q{}^r{}_s{}_t{}^g{}^v{}^h{}_x[/math]

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[math]\displaystyle {\large £}[V{}^{u}] \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} = V{}^{u} \partial{}_{u} \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} - \sum_{\phi = 1}^{p} \partial{}_{u} V{}^{i_\phi}\ \mathfrak{T}{}^{i_1\ .\ .\ .\ i_{\phi - 1}\ u\ i_{\phi + 1}\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} + \sum_{\phi = 1}^{q} \partial{}_{j_\phi} V{}^{u}\ \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_{\phi - 1}\ u\ j_{\phi + 1}\ .\ .\ .\ j_q} +\ w\ \partial{}_{u} V{}^{u}\ \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q}[/math]

[math]\displaystyle \overline{{\large £} [V{}^{v}] \mathfrak{T}}{}^{r_1\ .\ .\ .\ r_p}_{s_1\ .\ .\ .\ s_q} = {\large £}[V{}^{u}] \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} \left(\prod_{\lambda = 1}^{p} \dfrac{\partial \overline{x}{}^{r_\lambda}}{\partial x{}^{i_\lambda}}\right) \left(\prod_{\lambda = 1}^{q} \dfrac{\partial x{}^{j_\lambda}}{\partial \overline{x}{}^{s_\lambda}}\right) \left|\dfrac{\partial x{}^{j}}{\partial \overline{x}{}^{s}}\right|^w[/math]

Edited by KJW

13 hours ago, KJW said:

£[Vu]Ti1 . . . ipj1 . . . jq=Vu∂uTi1 . . . ipj1 . . . jq−∑ϕ=1p∂uViϕ Ti1 . . . iϕ−1 u iϕ+1 . . . ipj1 . . . jq+∑ϕ=1q∂jϕVu Ti1 . . . ipj1 . . . jϕ−1 u jϕ+1 . . . jq+ w ∂uVu Ti1 . . . ipj1 . . . jq

£[Vv]T¯¯¯¯¯¯¯¯¯¯¯¯¯¯r1 . . . rps1 . . . sq=£[Vu]Ti1 . . . ipj1 . . . jq(∏λ=1p∂x¯¯¯rλ∂xiλ)(∏λ=1q∂xjλ∂x¯¯¯sλ)∣∣∣∂xj∂x¯¯¯s∣∣∣w

This looks intimidating... What sort of beast is it?

  • Author

Bear in mind this is "The Sandbox" used for testing how the forum behaves, such as LaTeX code. However, the mathematics itself is about the Lie derivative, a tensorial derivative that is different to the covariant derivative and is independent of the connection.

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On 4/15/2026 at 8:13 PM, Anton Rize said:
On 4/15/2026 at 6:22 AM, KJW said:

[math]\displaystyle {\large £}[V{}^{u}] \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} = V{}^{u} \partial{}_{u} \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} - \sum_{\phi = 1}^{p} \partial{}_{u} V{}^{i_\phi}\ \mathfrak{T}{}^{i_1\ .\ .\ .\ i_{\phi - 1}\ u\ i_{\phi + 1}\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} + \sum_{\phi = 1}^{q} \partial{}_{j_\phi} V{}^{u}\ \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_{\phi - 1}\ u\ j_{\phi + 1}\ .\ .\ .\ j_q} +\ w\ \partial{}_{u} V{}^{u}\ \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q}[/math]

[math]\displaystyle \overline{{\large £} [V{}^{v}] \mathfrak{T}}{}^{r_1\ .\ .\ .\ r_p}_{s_1\ .\ .\ .\ s_q} = {\large £}[V{}^{u}] \mathfrak{T}{}^{i_1\ .\ .\ .\ i_p}_{j_1\ .\ .\ .\ j_q} \left(\prod_{\lambda = 1}^{p} \dfrac{\partial \overline{x}{}^{r_\lambda}}{\partial x{}^{i_\lambda}}\right) \left(\prod_{\lambda = 1}^{q} \dfrac{\partial x{}^{j_\lambda}}{\partial \overline{x}{}^{s_\lambda}}\right) \left|\dfrac{\partial x{}^{j}}{\partial \overline{x}{}^{s}}\right|^w[/math]

This looks intimidating... What sort of beast is it?

On 4/15/2026 at 8:53 PM, KJW said:

However, the mathematics itself is about the Lie derivative, a tensorial derivative that is different to the covariant derivative and is independent of the connection.

I should also remark that the mathematics is stock standard mathematics used in general relativity. That you call it "intimidating" is revealing about your understanding of general relativity. I personally regard the mathematics as beautiful, although actually doing the mathematics, especially the index manipulations, can be quite tedious to do manually.

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