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    • Added pointers concerning the suggestion that the observed Higgs mass is related to asymptotic safety.

      diff, v7, current

    • tried to polish a little and slightly expand model category, starting with the Definition-section and ending with the (new and tiny) Properties section. Added some more subsections and so on.

    • Added redirects and a description of other contributions.

      diff, v2, current

    • Removed an incorrect historical claim (Dwyer and Kan did throughly investigate relative categories already in 1980s, way before 2000s).

      Added a section about model structures.

      diff, v3, current

    • Page created, but author did not leave any comments.

      v1, current

    • Geometry Gems is no longer available


      diff, v165, current

    • Hello, I added some words about an ambiguity I found in the literature about the name “dilatino”. If I am wrong, I’d be thankful to the one who makes me notice the mistake!

      diff, v2, current

    • need the link, but nothing here yet

      v1, current

    • stated the definition Δf=ddf\Delta f = \star d \star d f and spelled out how this gives the usual component formula:

      ddf =d( jf)dx j =d(1(D1)!|det((g ij))|g ij( jf)ε ik 2k Ddx k 2dx k D) = k 1(1(D1)!|det((g ij))|g ij( jf)ε ik 2k Ddx k 1dx k 2dx k D) =|det((g ij))|1D!(D1)!ε l 1l 2l Dg l 1k 1g l 2k 2g l Dk Dε ik 2k D=det((g ij) 1)δ i k 1 k 1(|det((g ij))|g ij( jf)) =1|det((g ij))|δ i k 1 k 1(|det((g ij))|g ij( jf)) =1|det((g ij))| i(|det((g ij))|g ij( jf)) \begin{aligned} \star d \star d f & = \star d \star (\partial_j f) d x^j \\ & = \star d \left( \tfrac{1}{ \color{green} (D-1)! } \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } \, g^{ i j} (\partial_j f) \, \epsilon_{ i {\color{green} k_2 \cdots k_{D} } } d x^{ \color{green} k_2 } \wedge \cdots \wedge d x^{ \color{green} k_{D} } \right) \\ & = \star \partial_{ \color{magenta} k_1} \left( \tfrac{1}{ \color{green} (D-1)! } \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } \, g^{i j} (\partial_j f) \, \epsilon_{ i {\color{green} k_2 \cdots k_{D} } } d x^{ \color{magenta} k_1 } \wedge d x^{ \color{green} k_2 } \wedge \cdots \wedge d x^{ \color{green} k_{D} } \right) \\ & = \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } \underset{ = \det\big( (g_{i j})^{-1} \big) \delta^{ \color{magenta} k_1 }_i }{ \underbrace{ \tfrac{1}{ { \color{orange} D! } { \color{green} (D-1)! } } \epsilon_{ \color{orange} l_1 l_2 \cdots l_D } g^{ { \color{orange} l_1 } { \color{magenta} k_1 } } g^{ { \color{orange} l_2 } { \color{green} k_2 } } \cdots g^{ { \color{orange} l_D} { \color{green} k_D } } \epsilon_{ i {\color{green} k_2 \cdots k_{D} } } } } \, \partial_{ \color{magenta} k_1 } \left( \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } g^{i j} (\partial_j f) \right) \\ & = \frac{1}{ \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } } \delta^{ \color{magenta} k_1 }_i \partial_{ \color{magenta} k_1 } \left( \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } g^{i j} (\partial_j f) \right) \\ & = \frac{1}{ \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } } \partial_{i} \left( \sqrt{ \left\vert det\big( (g_{i j}) \big) \right\vert } g^{i j} (\partial_j f) \right) \end{aligned}

      diff, v7, current

    • expanded brane

      first a little remark on what D-branes are abstractly, in reply to an MO-question, then something on fundamental branes, going along with the discussion on the Café

    • brief category:people entry in order to make hyperlinks work

      v1, current

    • Hello,

      I noticed DFT page has not been updated in a while and I added a couple of sections: some sketchy introductory material (analogy between Kaluza-Klein and DFT) and a little insight about a more rigorous geometrical formulation of DFT.

      It is still quite sketchy but I would be happy to refine it.

      PS: this is my first edit, I hope I played by the rules. And thank you all for this wiki


      diff, v7, current

    • The entry Clifford algebra used to state the classification and Bott periodicty over the complex numbers, but not over the real numbers. I have added in now the relevant statements, straight from Lawson-Michelson:

      Just the bare statements so far.

    • I added some discussion to Hausdorff space of how the localic and spatial versions compare in classical and constructive mathematics, including in particular the fact that I just learned (in discussion with Martin Escardo and Andrej Bauer) that a discrete locale is Hausdorff iff it has decidable equality.

    • added a table (here) showing the first-generation mesons as irreps of the spacetime ×\times isospin symmetry group

      diff, v15, current

    • Add a note about “Daniel’s answer” to the semantics-structure question. The discussion on this page should really be merged into the main text and archived at the forum.

      diff, v18, current