--- tags: - sentence-transformers - sentence-similarity - feature-extraction - generated_from_trainer - dataset_size:264888 - loss:CosineSimilarityLoss base_model: sentence-transformers/all-MiniLM-L6-v2 widget: - source_sentence: "latex_in_original_or_summarized: K(M, n)\n\n[SEP]\n\nsummarized:\ \ $K(M, n)$\n\n[SEP]\n\nmain_note_content: Chain complexes and spaces. [59],\ \ that for simplicial sheaf $\\text{X}$ we denote by $C_{*}(\\mathcal{X})$\ \ the (normalized) chain complex $C_{*}(\\mathcal{A}$ associated to the sheaf\ \ abelian groups $\\mathbb{X}$. This defines a functor\n\n$$ C_{*}: \\Delta^{o\ \ p} S h v_{N i s}\\left(S m_{k}\\right) C_{*}(\\text{A} b(k)) $$$ ^f7eebc\n\ \nwhich is well (see $[44,59]$ instance) to have a right adjoint\n\n6.2 \\mathbb{A}^{1}$-Derived\ \ Category Spaces\n161\n\n$$ K: C_{*}(\\mathcal{A} b(k)) \\rightarrow \\phi^{o\ \ p} S h v_{N i s}\\left(S $$ \n\n\ncalled the space \n\nFor an abelian $M\ \ b(k)$ and an integer $n$ we define the pointed simplicial sheaf $K(M, n)$\ \ (see [59, page 56]) $K$ to the shifted complex $M[n]$, the complex $M$ placed\ \ in degree 0 . If n< 0, the space $K(M, n)$ is a point. If $n \\geq 0$ then $K(M,\ \ n)$ has only one non-trivial sheaf which is the and which is canonically isomorphic\ \ to $M$. More generally, for a chain $C_{*}$, $K C_{*}$ has homotopy sheaf\ \ 0 $n< 0$, and the $n$-th homology sheaf $H_{n}\\left(C_{*}\\right)$ for $n\ \ \\geq 0$.\n\nIt is clear that $C_{*}: \\Delta^{o p} S h i s}\\left(S m_{k}\\\ right) \\rightarrow b(k))$ sends simplicial weak equivalences to quasi-isomorphisms\ \ and $K: C_{*}(A b(k)) \\rightarrow \\Delta^{o p} S h v_{N i s}\\left(S m_{k}\\\ right)$ maps quasi-isomorphisms to simplicial equivalences. If $C_{*}$ fibrant,\ \ it follows that $K\\left(C_{*}\\right)$ is simplicially Thus the two functors\ \ induce a pair of adjoint functors\n\n$$ C_{*}: \\mathcal{H}{s}(k) \\rightarrow\ \ D(\\mathcal{A} b(k)) $$ ^c4a825\n\n\n\n$$ K: D(\\mathrm{A} b(k)) \\rightarrow\ \ \\mathcal{H}_{s}(k) $$ \n\nAs a consequence it is clear that is an $\\mathscr{A}^{1}$-local\ \ complex, space $K\\left(C_{*}\\right)$ is an $\\mathbb{A}^{1}$-local space.\ \ Thus $C_{}: \\mathbf{H}_{s}(k) \\rightarrow maps $\\mathcal{A}^{1}$-weak \ \ to $\\mathrm{A}^{1}$-quasi and induces a functor\n\n \\rightarrow D_{\\\ mathbb{A}^{1}}(A b(k)) $$ \n\nwhich in concrete terms, maps a space $\\operatorname{X}$\ \ to the $\\mathbb{A}^{1}$-localization of $C_{*}(\\mathcal{X})$. We denote the\ \ latter by $C_{*}^{A^{1}}(\\mathbb{X})$ and call it the $\\mathbb{A}^{1}$-chain\ \ of $\\mathcal{X}$. functor $C_{*}^{\\operatorname{A}^{1}}: \\mathfrak{H}(k)\ \ \\rightarrow b(k))$ admits as right adjoint the functor $K^{\\mathbb{A}^{1}}:\ \ D_{\\mathbb{A}^{1}}(\\mathcal{A} b(k)) \\rightarrow \\mathcal{H}(k)$ induced\ \ by $C_{*} \\mapsto K\\left(L_{\\mathbb{A}^{1}}\\left(C_{*}\\right)\\right)$.\ \ We that for an $\\mathbb{A}^{1}$-local complex the space $K\\left(C_{*}\\\ right)$ is automatically $\\mathbb{A}^{1}$-local and thus simplicially equivalent\ \ to the space \n\n\n[SEP]\n\nprocessed_content: the pointed simplicial where\ \ $M$ \\in b(k)$ and $n$ is integer. It is defined by applying to the complex\ \ $M[n]$, of the complex degree 0 ." sentences: - "latex_in_original_or_summarized: \\gamma_1=(m_1,N_1,a_1)\n\n[SEP]\n\nsummarized:\ \ $\\gamma_1=(m_1,N_1,a_1)$\n\n[SEP]\n\nmain_note_content: \\begin{notation}\\\ label{Dep1}\nLet $\\gamma_1=(m_1,N_1,a_1)$, $\\gamma_2=(m_2,N_2,a_2)$ be an ordered\ \ pair of \n(generalized) monodromy data which hypothesis (A). Assume that $m_1|m_2$.\n\ Set $d:=m_2/m_1$ and $r:=\\gcd(m_1, a_1(N_1))$. \nThen, \\eqref{Dep} to \n$\\\ epsilon=d(r-1)$ and $g_3=dg_1+g_2+\\epsilon$.\nIn particular, $\\epsilon=0$ if\ \ and if $r=1$. \n\\end{notation}\n\n\n[SEP]\n\nprocessed_content: " - 'latex_in_original_or_summarized: \langle u\rangle G W(F) [SEP] summarized: $\langle u\rangle \in G W(F)$ [SEP] main_note_content: Let us denote (in characteristic) by $G W(F)$ the Grothendieck-Witt ring of isomorphism classes of non-degenerate symmetric bilinear forms [48]: this is the group completion of the commutative monoid of isomorphism classes of non-degenerate symmetric forms for the direct sum. For $u \in F^{\times}$, we denote by $\langle u\rangle G W(F)$ the form on vector space of rank one given by $F^{2} F,(x, \mapsto u x y .$ By the results of loc. \langle u\rangle$ generate $G as a group. The following Lemma is (essentially) [48, Lemma (1.1) Chap. IV]: [SEP] processed_content: ' - 'latex_in_original_or_summarized: $\varepsilon_{\infty}$ [SEP] summarized: $\varepsilon_{\infty}$ [SEP] main_note_content: To compute the genus of $X(\kappa)$, further specialize to $\Gamma_{1}=\Gamma$ and $\Gamma_{2}=$ $\mathfrak{SL}_{2}(\mathbb{Z}) . Let $y_{2}=\mathrm{SL}_{2}(\mathbb{Z}) i, y_{3}=\mathrm{SL}_{2}(\mathbb{Z}) \mu_{3}$, and $y_{\infty}=\mathfrak{SL}_{2}(\mathbb{Z}) \infty$ be the elliptic point of period 2, the elliptic point of period 3, and the cusp of $X(1)=$ SL_{2}(\mathbb{Z}) \backslash \mathcal{H}^{*} .$ Let $\varepsilon_{2}$ and $\varepsilon_{3}$ be the number of elliptic points of $\Gamma$ in $f^{-1}\left(y_{2}\right)$$ and of^{-1}\left(y_{3}\right)$, i.e., the number of elliptic points of period 2 and 3 in $X(\Gamma)$, and let $\varepsilon_{\infty}$ be the number of cusps of X(\Gamma) .$ Then recalling that $d=\operatorname{deg}(f)$ and letting $h=2$ or $h=3$, the formula for $d$ at the beginning of the section and then the formula for $e_{\pi_{1}(\tau)}$ at the nonelliptic points and the elliptic points over $\mathrm{SL}_{2}(\mathscr{Z}) y_{h}$ show that (Exercise 3.1.3(a)) $$ d=\sum_{x \in f^{-1}\left(y_{h}\right)} e_{x}=h \cdot\left(\left|f^{-1}\left(y_{h}\right)\right|-\varepsilon_{h}\right)+1 \cdot \varepsilon_{h} $$ and using these equalities twice gives $$ \sum_{x \in f^{-1}\left(y_{h}\right)}\left(e_{x}-1\right)=(h-1)\left(\left|f^{-1}\left(y_{h}\right)\right|-\varepsilon_{h}\right)=\frac{h-1}{h}\left(d-\varepsilon_{h}\right) $$ $68 \quad 3$ Dimension Formulas Also. $$ \sum_{x \in f^{-1}\left(y_{\infty}\right)}\left(e_{x}-1\right)=d-\varepsilon_{\infty} $$ Since $X(1)$ has genus 0, the Riemann-Hurwitz formula now shows [SEP] processed_content: ' - source_sentence: "latex_in_original_or_summarized: $M_\\ell(C \\to S) = M_\\ell(S)$\n\ \n[SEP]\n\nsummarized: $M_\\ell(C \\to S) = M_\\ell(S)$\n\n[SEP]\n\nmain_note_content:\ \ If $C \\to S$ is a relative smooth proper curve of genus $g \\geq 1$ over an\ \ irreducible base, then the $\\ell$-torsion of relative Jacobian of $C$ information\ \ about the family. Suppose $\\ell$ is invertible on $S$, and let \\in S$ be\ \ a geometric point. The fundamental group $\\pi_1(S,s)$ acts\nlinearly on the\ \ fiber $\\operatorname{Pic}^0(C)[\\ell]_{s} \\cong (\\mathbb{Z}/\\ell)^{2g}$,\ \ \none can consider the mod-$\\ell$ representation associated to $C$:\n\n$$\\\ rho_{C \\to S, \\ell}:\\pi_1(S,s) \\rightarrow \\cong \\operatorname{GL}_{2g}(\\\ mathbb{Z}/\\ell).$$ ^e59a92\n\nLet $M_\\ell(C \\to S)$, or simply $M_\\ell(S)$,\ \ be the image\nof this representation. \nIf a primitive $\\ell$th root of is\ \ defined $S$, then $\\operatorname{Pic}^0(C)[\\ell]_{s}$ is equipped\nwith\ \ a skew-symmetric form $\\langle \\cdot,\\cdot and $M_\\ell(C \\to S) \\subseteq\n\ \\operatorname{Sp}(\\operatorname{Pic}^0(C)[\\ell]_s,\\langle \\rangle) \\cong\n\ \\operatorname{Sp}_{2g}(\\mathbb{Z}/\\ell)$. \nIf C \\to S$ is a sufficiently\ \ general family of curves, then\n$M_\\ell(C \\to S) \\cong \\operatorname{Sp}_{2g}(\\\ mathbb{Z}/\\ell)$ \\cite{delignemumford}.\n\nIn this we compute when $S$ is\ \ an irreducible component of moduli space of hyperelliptic or trielliptic curves\ \ and $C \\to S$ is the tautological curve. The first result implies that there\ \ is no restriction on the monodromy group in the hyperelliptic case other than\ \ that it preserve the symplectic pairing. As trielliptic curve is a $\\mathbb{Z}/3$-cover\ \ of a genus zero curve, the $\\mathbb{Z}/3$-action constrains the monodromy\ \ group to lie in a unitary group associated to $\\mathbb{Z}[\\zeta_3]$. The second\ \ result implies that this is the only additional restriction in the trielliptic\ \ case. \n\n\\paragraph{Theorem \\ref{thhe}}\n{\\it \n $\\ell$ be an odd prime,\ \ and let $k$ be an closed in which $2\\ell$ is invertible.\nFor $g\\geq 1$,\ \ $M_\\ell(\\mathcal{H}_g\\otimes k)\\cong\n\\operatorname{Sp}_{2g}(\\mathbb{Z}/\\\ ell)$.}\n\n\\paragraph{Theorem \\ref{thtri}}\n{\\it \nLet $\\ell\\geq 5$ be prime,\ \ and let $k$ be closed field in which $3\\ell$ is invertible. \n$\\mathcal{T}^{\\\ bar\\gamma}$ be any component the moduli space \ntrielliptic curves of genus\ \ $g\\geq Then\n$M_\\ell(\\mathcal{T}^{\\bar\\gamma}\\otimes k) \\cong\n\\operatorname{SG}_{(r_\\\ gamma,s_\\gamma)}(\\mathbb{Z}/\\ell)$ (where the latter is unitary group defined\n\ in \\eqref{eqdefsg}).}\n\n\\medskip\n\nWe also prove that the $\\ell$-adic monodromy\ \ group \n$\\operatorname{Sp}_{2g}(\\mathbb{Z}_\\ell)$ in the situation of Theorem\ \ \\ref{thhe} and is $\\operatorname{SG}_{(r_\\gamma,s_\\gamma)}(\\mathbb{Z}_\\\ ell)$\nin the of Theorem \\ref{thtri}.\n\nTheorem \\ref{thhe} is an unpublished\ \ result J.K. Yu and has already been used multiple times in literature.\nIn\ \ \\cite{chavdarov}, Chavdarov assumes this result show that the numerator of\ \ the zeta function of\nthe typical hyperelliptic curve over a finite field is\ \ irreducible.\nKowalski also uses this result in a similar fashion \\cite{kowalskisieve}.\n\ The first author used Theorem to prove a conjecture of and\nWashington on class\ \ of quadratic function fields \n\nThere are other results in the literature\ \ which similar to Theorem \\ref{thhe}\nbut which are not quite strong enough\ \ for the above.\nA'Campo \\cite[Th.\\ 1]{acampo} computes the topological of\ \ $\\mathcal{H}_g \\otimes \nOn the arithmetic side, the $\\mathbb{Q}_\\ell$,\n\ as opposed to $\\mathbb{Z}_\\ell$, monodromy of $\\mathcal{H}_g$\nis computed\ \ in \\cite[10.1.16]{katzsarnak}. Combined with a theorem of\nLarsen on compatible\ \ families of representations \\cite[3.17]{larsenmax},\nthis shows that the mod-$\\\ ell$ group \nof $\\mathcal{H}_g$ is maximal for a set of\nprimes $\\ell$ of density\ \ one (as opposed to for all $\\ell \\geq 3$). \n\nThere are results on $\\mathbb{Q}_\\\ ell$-monodromy cyclic covers of the projective\nline of arbitrary degree, e.g.,\ \ \\cite[Sec. 7.9]{katztwisted}. Also,\nin \\cite[5.5]{fkv}, the authors prove\ \ that the projective representation\n$\\mathbb{P} \\rho_{C \\to S,\\ell}$ surjective\ \ for many\nfamilies of cyclic covers the projective line. \nDue to a combinatorial\ \ their theorem does not apply to $\\mathcal{H}_g$\nand applies to at most one\ \ component of the moduli space of\ntrielliptic curves for each see Remark \\\ ref{Rfkv}. \nSee also work of Zarhin, e.g., \\cite{zarhincyclic}.\n\n an application,\ \ for all $p \\geq show using \n exist hyperelliptic and trielliptic curves\n\ of every genus signature) defined over $\\bar{\\mathbb{F}}_p$ whose Jacobians\ \ absolutely simple.\nIn contrast with the applications above, \nthese corollaries\ \ do not use the full strength of our results.\nRelated can be found in \\cite{HZhu}\ \ authors produce curves with absolutely \nJacobians over $\\mathbb{F}_p$ under\ \ the $g \\leq 3$.\n\n\\paragraph{Corollary \\ref{Chypabsirr}} \n{\\it Let p\ \ \\not = 2$ let Then there exists a\nsmooth hyperelliptic curve of genus $g$\ \ over $\\bar{\\mathbb{F}}_p$ whose Jacobian is\nabsolutely simple.}\n\n\\paragraph{Corollary\ \ \\ref{Ctriabsirr}}\n{\\it Let $p \\not = 3$. $g 3$ and be a trielliptic\ \ signature for $g$\n \\ref{Dtrisig}). \nThen there exists a smooth trielliptic\ \ curve defined over with genus $g$ and signature $(r,s)$\nwhose Jacobian is\ \ simple.}\n\n\\medskip \n\nOur proofs proceed by induction on the genus.\nThe\ \ base cases for the family\nrely on the fact that every curve of genus $g=1,2$\ \ is hyperelliptic;\nthe claim on monodromy follows from the analogous assertion\ \ the monodromy of $\\mathcal{M}_g$.\nThe case for the trielliptic family involves\ \ a comparison with\na Shimura variety of PEL type, namely, the modular variety.\ \ \nAn important step is to show the monodromy group does not change in the\ \ base cases when \none adds a labeling of the ramification points to the moduli\ \ problem.\n\nThe step is similar to the method used in \\cite{ekedahlmono} \n\ and uses the fact that families of smooth hyperelliptic (trielliptic)\ncurves\ \ degenerate to trees of (trielliptic) curves of lower genus.\nThe combinatorics\ \ of admissible degenerations require us \nto compute the monodromy exactly for\ \ the inductive step rather than up to isomorphism. \n\nThe inductive strategy\ \ using admissible degeneration developed here\nshould work for other of curves,\ \ especially for more general\ncyclic covers of projective The difficulty is\ \ in direct\ncalculation of monodromy for the necessary base cases.\n\nWe thank\ \ C.-L.\\ Chai, R.\\ Hain, A.J.\\ de Jong, E. Kani, and J. Kass.\n\n\n[SEP]\n\n\ processed_content: the image of the mod-$\\ell$ representation $\\rho_{C \\to\ \ \\ell}$ of the relative smooth $C \\to S$ of genus $g \\geq 1$ over an irreducible\ \ base." sentences: - "latex_in_original_or_summarized: X^{\\vee}\n\n[SEP]\n\nsummarized: \n\n[SEP]\n\ \nmain_note_content: Let be principally polarized abelian scheme of\nrelative\ \ dimension $g$ over an irreducible base. \n\nIf $\\ell$ is a\nrational invertible\ \ on $S$, then the $\\ell$-torsion $X[\\ell]$ of\n$\\ell$ is an \\'etale cover\ \ of with geometric fiber isomorphic to\n$(\\mathbb{Z}/\\ell)^{2g}$. \nLet $s$\ \ be a geometric point of $S$. The group $\\pi_1(S,s)$ \nlinearly on the $\\\ ell$-torsion of $X$.\n\nThis yields a representation\n\n\\rho_{X \\to S, s,\\\ ell}: \\pi_1(S,s) \\rightarrow \\operatorname{Aut}(X[\\ell]_s) \\cong \\operatorname{GL}_{2g}(\\\ mathbb{Z}/\\ell).$$ ^dbec50\n\nThe cover $X[\\ell] \\to S$ both determines and\ \ is determined by representation \\to S, s,\\ell}$. \n\nThe image of \\to\ \ S, is the mod-$\\ell$ monodromy of $X \\to S$ and we denote it by $M_\\ell(X\ \ \\to S, s), or by $M_\\ell(S,s)$ if the choice of\nabelian scheme is clear.\n\ \nThe isomorphism class of the\n$M_\\ell(S,s)$ is independent of the choice of\ \ base point $s$,$ and we denote it $M_\\ell(S)$.\n\nLet $X^{\\vee}$ be the dual\ \ abelian scheme. There a pairing $X[\\ell] \\times X^{\\vee}[\\ell] \\to \\\ boldsymbol{\\mu}_{\\ell,S}$, where := \\boldsymbol{\\mu}_\\ell \\times S$ is\ \ group scheme of $\\ell\\th$ of unity.\n\n polarization induces an isomorphism\ \ $X \\to X^{\\vee}$, and\nthus a skew-symmetric pairing $X[\\ell] \\times X[\\\ ell] \\to \\boldsymbol{\\mu}_{\\ell,S}$.\nBecause the polarization is defined\ \ globally, the image of monodromy\n$M_\\ell(X \\to S, s)$ is contained in the\ \ group of symplectic\nsimilitudes of $(X[\\ell]_s,\n\\langle \\rangle_\\phi)$,\ \ which is isomorphic to\n$\\operatorname{GSp}_{2g}(\\mathbb{Z}/\\ell)$. Moreover,\ \ if a primitive $\\ell^{{\\rm root of\nunity globally on $S$, $\\pi_1(S,s)$\ \ acts trivially on\n$\\boldsymbol{\\mu}_{\\ell,S}$ and $M_\\ell(X \\to S,s) \\\ subseteq \\cdot,\\cdot \\rangle_\\phi) \\cong \\operatorname{Sp}_{2g}(\\mathbb{Z}/\\\ ell).\n\nSimilarly, the $X[\\ell^n] S$ defines a monodromy representation \n\ with in $\\operatorname{Aut}(X[\\ell^n]_s) \\cong\\operatorname{GL}_{2g}(\\mathbb{Z}/\\\ ell^n)$. Taking\n inverse limit over all n, we obtain a continuous representation\ \ on the Tate module of $X$, \n\n$$\\rho_{X \\to S, s}: \\pi_1(S,s) \\rightarrow\ \ \\varprojlim_n \\operatorname{Aut}(X[\\ell^n]_s) \\cong \\operatorname{GL}_{2g}(\\\ mathbb{Z}_\\ell).$$\n\n^f6240a\n\nWe denote the image of this representation by\ \ $M_{\\mathbb{Z}_\\ell}(X \\to and its isomorphism class by $M_{\\mathbb{Z}_\\\ ell}(X \\to S)$ or $M_{\\mathbb{Z}_\\ell}(S)$. \n\nAgain, there is an \nM_{\\\ mathbb{Z}_\\ell}(X \\to S) \\subseteq \n\nIf\n$F$ is a field, let $F_{\\ell^\\\ infty} = F(\\boldsymbol{\\mu}_{\\ell^\\infty}(\\bar F))$. If $S$ is an then \n\ \n$$M_{\\mathbb{Z}_\\ell}(X \\to S, s)/ F} \\to S \\otimes{\\bar F}, s) \\cong\ \ ^dd1bab\n\nFinally, let $M_{\\mathbb{Q}_\\ell}(X\\to$ S, s)$ be the Zariski\ \ closure of \\to S, s)$ in $\\operatorname{GL}_{2g}(\\mathbb{Q}_\\ell)$.\n\n\ Now suppose that \\psi:C \\to S$ is a relative proper semi-stable curve.\n\nLet\ \ $\\operatorname{Pic}^0(C) := \\operatorname{Pic}^0_{C/S}$ be the neutral component\ \ of the relative Picard of $C$ over $S$. Since $C/S$ semi-stable, $\\operatorname{Pic}^0(C)$\ \ is a semiabelian scheme [[bosch_lutkebohmert_raynaud_nm_Theorem 1_page_259|\\\ cite[9.4.1]{blr}]]. \n\nSuppose that there is least one geometric point such\ \ the fiber $\\operatorname{Pic}^0(C_s)$ is an abelian variety. (This is true[^5]\ \ if some $C_s$ is a tree smooth curves.) Then there is a nonempty open subscheme\ \ $S^*$ of $S$ such that $\\operatorname{Pic}^0(C|_{S^*})$ an abelian scheme\ \ over $S^*$. \n\n[^5]: cf. Abelian varieties isogenous to a Jacobian by CL Chai,\ \ which talks about a tree of smooth curves having a Jacobian that is an abelian\ \ variety that is actually the product of the Jacobians of irreducible \n\nWe\ \ define the mod-$\\ell$ and $\\mathbb{Z}_\\ell$ monodromy representations of\ \ $C$ to be those of $\\operatorname{Pic}^0(C|_{S^*}) \\to S^*$.\n\n(Alternatively,\ \ may constructed as the restrictions of $R^1\\psi_*\\boldsymbol{\\mu}_{\\ell,S}$\ \ and $R^1\\psi_*\\boldsymbol{\\mu}_{\\ell^\\infty,S}$ largest subscheme of\ \ $S$ on which these sheaves are unramified.)\n\nThus, $M_\\ell(C \\to s) = M_\\\ ell(\\operatorname{Pic}^0(C|_{S^*}) \\to S^*, s)$, and we denote this again by\ \ M_\\ell(S,s) if the curve is clear and by the base point is suppressed. ^37a851\n\ \nThe moduli spaces $\\overline{\\mathcal{M}}_G$ and $\\widetilde{\\mathcal{M}}_G$\ \ are Deligne-Mumford stacks, and we employ a similar formalism for \\'etale covers\ \ of stacks \\cite{noohi}. \n\n $\\mathcal{S}$ a connected Deligne-Mumford \ \ The category of Galois \\'etale covers of $\\mathcal{S}$ is a Galois category\ \ the sense of Grothendieck, and thus there is \\'etale fundamental\n of More\ \ precisely, let $s\\in \\mathcal{S}$ be a geometric\n \n\nThen there is a group\ \ $\\pi_1(\\mathcal{S},s)$ and an equivalence of between finite $\\pi_1(\\mathcal{S},s)$-sets$\ \ and finite \\'etale Galois covers of $\\mathcal{S}$. \n\nIf $\\mathcal{S}$ has\ \ a coarse moduli space $S_{\\mathrm{mod}}$, then $\\pi_1(\\mathcal{S},s)$ is\ \ the extension of $\\pi_1(S_{\\mathrm{mod}},s)$ by a group which encodes extra\ \ automorphism structure on the moduli space S_{\\mathrm{mod}} [[noohi_fgas_thm\ \ 7.11|\\cite[7.11]{noohi}]]. \n\nIf $X \\to \\mathcal{S}$ is a family of abelian\ \ varieties, we again let $M_\\ell(X\\to be the of $\\pi_1(\\mathcal{S}, s)$\ \ in ^758472\n\nLet $\\mathcal{C}^\\gamma$ be the tautological labeled curve\ \ over\n By the mod-$\\ell$ or $\\mathbb{Z}_\\ell$ monodromy of\n$\\widetilde{\\\ mathcal{M}}_G^\\gamma$ we mean of $C^\\gamma \\to \\widetilde{\\mathcal{M}}_G^\\\ gamma$. [^6]\n\n[^6]: #_meta/TODO/question that that $C^\\gamma \\to \\widetilde{\\\ mathcal{M}}_G^\\gamma$ gets to have relative Picard group of its own? How does\ \ that make sense when $\\widetilde{\\mathcal{M}}_G^\\gamma$ a is not a scheme?\n\ \n\n[SEP]\n\nprocessed_content: the dual abelian scheme of the abelian scheme\ \ $X/S$. There is a canonical pairing $X[\\ell] \\times X^{\\vee}[\\ell] \\to\ \ \\boldsymbol{\\mu}_{\\ell,S}$, where $\\boldsymbol{\\mu}_{\\ell,S} := \\boldsymbol{\\\ mu}_\\ell \\times S$ is group scheme of $\\ell\\th$ roots of unity." - "latex_in_original_or_summarized: \\mathbb{Th}_f \\phi\n\n[SEP]\n\nsummarized:\ \ $_f \n\n[SEP]\n\nmain_note_content: It be convenient to work in stable category\ \ $\\mathcal{Spt}(B)$$ of $P^1$-spectra over $B$, where $B$ is a finite type scheme\ \ over frequently, $B=L$, where $L$ is a field extension of $k$. \n\nThe notation\ \ be the morphisms. $(B)$ is a monoidal category under smash product $\\\ wedge$, with $1_B$, denoting the sphere spectrum. \n\nAny pointed simplicial\ \ presheaf $X$ determines corresponding $\\mathbb{P}^1$-suspension spectrum $\\\ Sigma^{\\infty} X$. \n\nFor $\\Sigma^{} Spec L_+ 1_L$ and $\\Sigma^{\\infty}\ \ (^1_L)^{ n}$ is a suspension When working in $\\operatorname{Spt}(L)$, we\ \ will identify pointed $X$ with their spectra $\\Sigma^{} X$, omitting the\ \ $\\Sigma^{\\infty}$. ^1246cf\n\nWe will use six operations $(p^*, p_!, p^!,\ \ \\wedge, given by Ayoub developed by Ayoub, and Cisinksi-Déglise \\cite{CD-triang_cat_mixed_motives}.\ \ There a nice summary in \\cite[\\S \n\nWe use following associated notation\ \ and constructions. \n\nWhen \\to Y$ is smooth, $p^*$ admits a left denoted\ \ p_{\\sharp}, induced by forgetful functor \\to \\operatorname{Sm}_{Y}$ from\ \ smooth over $X$ smooth schemes over $Y$. \n\nFor $p:X\\to \\operatorname{Spec}\ \ L$ a smooth scheme over $L$, the suspension spectrum of $X$ is canonically identified\ \ with as an object of $\\operatorname{Spt}(L)$. \n\nFor a vector bundle $p:E\ \ \\to X$, the Thom spectrum Th(E)$ (or just is canonically identified $s^*p^!\ \ 1_X$[^2]. \n\n Perhaps $s$ a fixed section of $p$.$\n\nLet $\\Sigma^E$ equal\ \ $\\Sigma^E = s^* p^!: (X) \\to (X)$. Let $e: \\to X and $d: D Y$ be two vector\ \ bundles over smooth $p: X L$ and $q:Y \\operatorname{Spec} L$. ^123eb1\n\ \nGiven a map $f: Y \\to X$ and a monomorphism $\\phi: D \\hookrightarrow f^*\ \ there is an associated natural transformation ^0f1ba8\n\n$$_f \\phi : q^!\ \ p_! \\Sigma^E p^!$$\n\nof endofunctors on $(L)$ inducing the map on Thom spectra.\ \ The \\phi$ is defined as composition ^0b33ea\n\n\\begin{equation}\\operatorname{Th}_f\ \ = {1_{f^*E}} \\circ .\\end{equation}$$\n\nThe natural $\\operatorname{Th}_{1_Y}\ \ is the composition t^*d^! t^* ^!e^!\\to t^* \\phi^* e^! \\cong e^!,$$ where\ \ $t: D$ denotes the zero section of $D$, $s: X \\to E$ denotes the zero $E$,\ \ and the middle arrow is by the exchange transformation $\\phi^! \\cong \\\ to 1^! \\phi^* \\cong natural transformation $\\operatorname{Th}_f the composition\ \ \n\n$$\\begin{equation}\\operatorname{Th}_f 1: q_! \\Sigma^{f^* E} q^! \\cong\ \ p_! f^! p^! \\cong p_!^E f_! f^! p^! {\\rightarrow} p_! ^E p^!,\\end{equation}$$\n\ \nwhere $: f_! f^! \\to 1$ denotes the counit.\n\n\n[SEP]\n\nprocessed_content: " - "latex_in_original_or_summarized: j_0: \\mathbb{G}_m / \\bar{k} \\subset \\mathbb{A}^1\ \ / \n\n[SEP]\n\nsummarized: $j_0$\n\n[SEP]\n\nmain_note_content: In order to\ \ explain the simple underlying ideas, we will admit four statements, and explain\ \ how to deduce from them equidistribution theorems about the sums $S(M, k, \\\ chi)$ as $\\chi$ varies.\n\n(1) If $M$ and $N$ are both perverse on $\\mathbb{G}_m\ \ / k$ (resp. on $\\mathbb{G}_m / \\bar{k}$ ) and satisfy $\\mathcal{P}$, then\ \ their middle convolution $M _{\\text {mid }} N$ is perverse on $\\mathbb{G}_m\ \ / k$ (resp. on $\\mathbb{G}_m / \\bar{k}$ ) and satisfies $\\mathcal{P}$.\n\n\ (2) With the operation of middle convolution as the \"tensor product,\" the skyscraper\ \ sheaf $\\delta_1$ as the \"identity object,\" and $[x \\mapsto 1 / x]^{\\star}\ \ D M$ as the \"dual\" $M^{\\vee}$ of $M$ ( $D M$ denoting the Verdier dual of\ \ $M$ ), the category of perverse sheaves on $\\mathbb{G}_m / k$ (resp. on $\\\ mathbb{G}_m / \\bar{k}$ ) satisfying $\\mathcal{P}$ is a neutral Tannakian category,\ \ in which the \"dimension\" of an object $M$ is its Euler characteristic $_c\\\ left(_m / , M\\right)$.\n\n(3) Denoting by\n\n$$ j_0: \\mathbb{G}_m / \\bar{k}\ \ \\subset \\mathbb{A}^1 / \\bar{k} $$ ^212b11\n\n1. OVERVIEW\n\n11\n\nthe inclusion,\ \ the construction\n\n$$ M \\mapsto H^0\\left(\\mathbb{A}^1 / \\bar{k}, j_{0!}\ \ M\\right) $$ ^425e70\n\nis a fibre functor on the Tannakian category of perverse\ \ sheaves on $\\mathbb{G}_m / \\bar{k}$ satisfying $\\mathcal{P}$ (and hence also\ \ a fibre functor on the subcategory of perverse sheaves on $\\mathbb{G}_m / k$\ \ satisfying $\\mathcal{P}$ ). For $i \\neq 0, H^i\\left(\\mathbb{A}^1 / \\bar{k},\ \ j_{0!} M\\right)$ vanishes.\n\n(4) For any finite extension field $E / k$, and\ \ any multiplicative character $\\rho$ of $E^{\\times}$, the construction\n\n\ $$ M \\mapsto H^0\\left(\\mathbb{A}^1 / \\bar{k}, j_{0!}\\left(M \\otimes \\\ mathcal{L}_\\rho\\right)\\right) $$ ^f07855\n\nis also such a fibre functor.\ \ For $i \\neq 0, H^i\\left(\\mathbb{A}^1 / \\bar{k}, j_{0!}\\left(M \\otimes\ \ \\mathcal{L}_\\rho\\right))$ vanishes.\n\nNow we make use of these four statements.\ \ Take for $N$ a perverse sheaf on $\\mathbb{G}_m / k$ which is $\\iota$-pure\ \ of weight zero and which satisfies $\\mathcal{P}$. Denote by $\\langle N\\rangle_{\ \ {arith }}$ the full subcategory of all perverse sheaves on $\\mathbb{G}_m /\ \ k$ consisting of all subquotients of all \"tensor products\" of copies of $N$\ \ and its dual $N^{\\vee}$. Similarly, denote by $\\langle N\\rangle_{ {geom }}$\ \ the full subcategory of all perverse sheaves on $\\mathbb{G}_m / \\bar{k}$ consisting\ \ of all subquotients, in this larger category, of all \"tensor products\" of\ \ copies of $N$ and its dual $N^{\\vee}$. With respect to a choice $\\omega$ of\ \ fibre functor, the category $\\langle N\\rangle_{\\text {arith }}$ becomes[^5]\ \ the category of finite-dimensional $\\overline{\\mathbb{Q}}_{\\ell}$-representations\ \ of an algebraic group $G_{a r i t h, N, \\omega} \\subset G L(\\omega(N))=G\ \ L('\\operatorname{dim}' N)$, with $N$ itself corresponding to the given \" dim\"\ \ $N$-dimensional representation. Concretely, $G_{arith,N, \\omega} \\subset\ \ G L(\\omega(N))$ is the subgroup consisting of those automorphisms $\\gamma$\ \ of $\\omega(N)$ with the property that $\\gamma$, acting on $\\omega(M)$, for\ \ $M$ any tensor construction on $\\omega(N)$ and its dual, maps to itself every\ \ vector space subquotient of the form $$ (any subquotient of $$ ).\n\n[^5]: Recall\ \ that associated to a neutral Tannakian category $(C, \\omega)$ is an affine\ \ algebraic group $G$ (called the Tannakian group or Tannakian dual of the neutral\ \ Tannakian category) and the fiber functor $\\omega$ induces an equivalence $C\ \ \\to \\operatorname{Rep}(G)$ of tensor categories, so $G_{\\text{arith}, N,\ \ \\omega}$ is being defined as this algebraic group for $\\langle N \\rangle_{\\\ text{arith}}$ under the choice of $\\omega$.\n\n^370dc9\n\nAnd the category $\\\ langle N_{\\text {geom }}$ becomes the category of finite-dimensional $\\overline{\\\ mathbf{Q}}_\\ell$-representations of a possibly smaller algebraic group $G_{\\\ text{geom}, N, \\omega} \\subset G_{\\text {arith }, N, \\omega}$ (smaller because\ \ there are more subobjects to be respected).\n\nFor $\\rho$ a multiplicative\ \ character of a finite extension field $E / k$, we have the fibre functor $\\\ omega_\\rho$ defined by\n\n$$ M \\mapsto H^0\\left(\\mathbb{A}^1 / \\bar{k},\ \ j_{!}\\left(M \\mathcal{L}_\\rho\\right)\\right) $$\n\non $\\langle N\\rangle_{\\\ text {arith }}$. The Frobenius $\\operatorname{Frob}_E$ is an automorphism of\ \ this fibre functor, so defines an element $\\operatorname{Frob}_{E, \\rho}$\ \ in the group $G_{a r i t h, N, _\\rho}$ defined[^5] by this choice of fibre\ \ functor. But one knows that the groups $G_{\\text {arith }, N, \\omega}$ (respectively\ \ the groups $G_{g e o m, N, \\omega}$ ) defined by different fibre functors are\ \ pairwise isomorphic, by a system of isomorphisms which are unique up to inner\ \ automorphism of source (or target). Fix one choice, say\n\n12\n\n1. OVERVIEW\n\ \n$\\omega_0$, of fibre functor, and define\n\n$$ G_{\\text {arith }, N}:=G_{\\\ text {arith }, N, \\omega_0}, \\quad G_{\\text {geom }, N}:=G_{\\text {geom },\ \ N, \\omega_0} . $$\n\nThen the element $Frob_{E, \\rho}$ in the group $G_{\\\ text {arith }, N, \\omega_\\rho}$ still makes sense as a conjugacy class in the\ \ group $G_{\\text {arith }, N}$.\n\nLet us say that a multiplicative character\ \ $\\rho$ of some finite extension field $E / k$ is good for $N$ if, for\n\n$$\ \ j: \\mathbb{G}_m / \\bar{k} \\subset \\mathbb{P}^1 / \\bar{k} $$\n\nthe inclusion,\ \ the canonical \"forget supports\" map\n\n$$ R j_1\\left(N \\otimes L_\\right)\ \ R j_{\\star}\\left(N \\otimes _\\rho\\right) $$\n\nis an isomorphism. If $\\\ rho$ is good for $N$, then the natural \"forget supports\" maps\n\n$$ H_c^0\\\ left(\\mathbb{G}_m / , N \\otimes \\mathcal{L}_\\rho\\right)=H_c^0\\left(\\mathbb{A}^1\ \ / \\bar{k}, j_{0!}(N \\otimes \\mathcal{L}_\\rho)\\right) \\rightarrow H^0\\\ left(\\mathbb{A}^1 / \\bar{k}, j_{0!}\\left(N \\otimes L_\\rho\\right)\\right),\ \ $$\n\ntogether with the restriction map\n\n$$ H^0\\left(^1 / \\bar{k}, j_{0!}(N\ \ \\otimes \\mathcal{L}_\\rho\\right)) H^0\\left(\\mathbb{G}_m , N _\\rho\\\ right), $$\n\nare all isomorphisms. Moreover, as $N$ is $$-pure of weight zero,\ \ each of these groups is $t$-pure of weight zero.\n\nConversely, if the group\ \ $\\omega_\\rho(N):=H^0(\\mathbb{A}^1 / \\bar{k}, j_{0!}\\left(N \\mathcal{L}_\\\ rho\\right))$ is $\\iota$-pure of weight zero, then $\\rho$ is good for $N$, and\ \ we have a \"forget supports\" isomorphism\n\n$$ H_c^0\\left(\\mathbb{G}_m /\ \ \\bar{k}, N \\otimes \\mathcal{L}_\\rho\\right) _\\rho(N):=H^0\\left(\\mathbb{A}^1\ \ / \\bar{k}, j_{0!}\\left(N \\otimes \\mathcal{L}_\\rho\\right)) . $$\n\nThis\ \ criterion, that $\\rho$ is good for $N$ if and only if $\\omega_\\rho(N)$ is\ \ $\\iota$-pure of weight zero, shows that if $\\rho$ is good for $N$, then $\\\ rho$ is good for every object $M$ in the Tannakian category $\\langle N\\rangle_{\\\ text {arith }}$ generated by $N$, and hence that for any such $M$, we have an\ \ isomorphism\n\n$$ H_c^0\\left(\\mathbb{G}_m / \\bar{k}, M \\otimes \\mathcal{L}_\\\ rho\\right) \\cong \\omega_\\rho(M) \\text {. } $$\n\nRecall that geometrically,\ \ i.e., on $\\mathbb{G}_m / \\bar{k}$, we may view the various Kummer sheaves\ \ $\\mathcal{L}_\\rho$ coming from multiplicative characters $\\rho$ of finite\ \ subfields $E \\subset \\bar{k}$ as being the characters of finite order of the\ \ tame inertia group $I(0)^{\\text {tame }}$ at 0 , or of the tame inertia group\ \ $I()^{ {tame }}$ at $\\infty$, or of the tame fundamental group $_1^{\\text\ \ {tame }}\\left(\\mathbb{G}_m / \\bar{k}\\right)$. In this identification, given\ \ a character $\\rho$ of a finite extension $E / k$ and a further finite extension\ \ $L / E$, the pair $(E, \\rho)$ and the pair ( $L, \\circ N o r m_{L / E}$ )\ \ give rise to the same Kummer sheaf on $\\mathbb{G}_m / \\bar{k}$. Up to this\ \ identification of $(E, \\rho)$ with $\\left(L, \\rho \\circ N o r m_{L / E}\\\ right)$, there are, for a given $N$, at most finitely many $\\rho$ which fail\ \ to be good for $N$ (simply because there are at most finitely many tame characters\ \ which occur in the local monodromies of $N$ at\n\n1. OVERVIEW\n\n13\n\neither\ \ 0 or $$, and we need only avoid their inverses). Indeed, if we denote by $r\ \ k(N)$ the generic rank of $N$, there are at most $2 r k(N)$ bad $\\rho$ for\ \ $N$.\n\nRecall [BBD, 5.3.8] that a perverse $N$ which is $\\iota$-pure of weight\ \ zero is geometrically semisimple. View $N$ as a faithful representation of $G_{\\\ text {geom,N }}$. Then $G_{\\text {geom,N }}$ has a faithful, completely reducible\ \ representation[^7], hence[^6] $G_{\\text {geom,N }}$ is a reductive group. ^260249\n\ \n[^7]: Apparently, \"completely reducible\" is a synonym for \"semisimple\",\ \ cf. https://math.stackexchange.com/questions/334178/definition-completely-reducible-group-representation\n\ \n[^6]: Milne's algebraic groups, Theorem 22.42 shows that the following are equivalent\ \ given a connected algebraic group $G$ over a field of characteristic $0$:\n\t\ 1. $G$ is reductive\n\t2. every finite-dimensional representation of $G$ is semisimple\n\ \t3. some faithful finite dimensional representation of $G$ is semisimple.\n\t\ See also the proof of forey_fresan_kowalski_aftff_3.18 Corollary, which uses this\ \ theorem.\n\nLet us now suppose further that $N$ is, in addition, arithmetically\ \ semisimple (e.g., arithmetically irreducible). Then $G_{a r i t h, N}$ is also\ \ a reductive group. Choose a maximal compact subgroup $K$ of the reductive Lie\ \ group $G_{\\text {arith }, N}(\\mathbb{C})$ (where we use $\\iota$ to view $G_{\\\ text {arith }, N}$ as an algebraic group over $\\mathbb{C}$ ). For each finite\ \ extension field $E / k$ and each character $\\rho$ of $E^{\\times}$ which is\ \ good for $N$, we obtain a Frobenius conjugacy class $_{E, \\rho}$ in $K$ as\ \ follows. Because $\\rho$ is good for $N$, $\\operatorname{Frob}_E$ has, via\ \ $\\iota$, unitary eigenvalues acting on $\\omega_\\rho(N)$, i.e., the conjugacy\ \ class $\\operatorname{Frob}_{E, \\rho}$ in $G_{\\text {arith }, N}$ has unitary\ \ eigenvalues when viewed in the ambient $G L\\left(\\omega_0(N)\\right)$. Therefore\ \ its semisimplification in the sense of the Jordan decomposition, $\\operatorname{Frob}_{E,\ \ \\rho}^{s s}$, is a semisimple class in $G_{\\text {arith }, N}()$ with unitary\ \ eigenvalues. Therefore any element in the class $\\operatorname{Frob}_{E, \\\ rho}^{s s}$ lies in a compact subgroup of $G_{arith , N}(\\mathbb{C})$ (e.g.,\ \ in the closure of the subgroup it generates), and hence lies in a maximal compact\ \ subgroup of $G_{\\text {arith,N }}()$. All such are $G_{\\text {arith }, N}(\\\ mathbb{C})$-conjugate, so we conclude that every element in the class $F r o b_{E,\ \ \\rho}^{s s}$ is conjugate to an element of $K$. We claim that this element\ \ is in turn well-defined in $K$ up to $K$-conjugacy, so gives us a $K$-conjugacy\ \ class $\\theta_{E, \\rho}$. To show that $\\theta_{E, \\rho}$ is well-defined\ \ up to $K$-conjugacy, it suffices, by Peter-Weyl, to specify its trace in every\ \ finite-dimensional, continuous, unitary representation $\\Lambda_K$ of $K$.\ \ By Weyl's unitarian trick, every $\\Lambda_K$ of $K$ is the restriction to $K$\ \ of a unique finite-dimensional representation $\\Lambda$ of the $\\mathbb{C}$-group\ \ $G_{\\text {arith }, N} / \\mathbb{C}$. Thus for every $\\Lambda_K$, we have\ \ the identity\n\n$\\operatorname{Trace}\\left(\\Lambda_K\\left(\\theta_{E, \\\ rho}\\right)\\right)=\\left(\\Lambda\\left(\\operatorname{Frob} _{E, }^{s s})\\\ right)=\\operatorname{Trace}\\left(\\Lambda\\left(\\operatorname{Frob} \\theta_{E,\ \ \\rho}\\right)\\right)$. ^d42132\n\nWith these preliminaries out of the way,\ \ we can state the main theorem.\n\n\n[SEP]\n\nprocessed_content: the inclusion\ \ \n\n$$ j_0: \\mathbb{G}_m / \\bar{k} \\mathbb{A}^1 / \\bar{k} $$\n\nThe construction\n\ \n$$ M \\mapsto H^0\\left(\\mathbb{A}^1 / \\bar{k}, j_{0!} M\\right) $$\n\n\ is a fibre functor on the Tannakian category of perverse sheaves on $\\mathbb{G}_m\ \ / $ satisfying $P$ (and hence also a fibre functor on the subcategory of perverse\ \ sheaves on $\\mathbb{G}_m / k$ satisfying $$ ). For $i \\neq 0, H^i\\left(\\\ mathbb{A}^1 / \\bar{k}, j_{0!} M\\right)$ vanishes." - source_sentence: "latex_in_original_or_summarized: F^i\n\n[SEP]\n\nsummarized: $F^i$\n\ \n[SEP]\n\nmain_note_content: no 3 - Examples of and eyact functors -\n Let\ \ $A$ be a category, $B$ an abelian An additive functor $F: A \\rightarrow B\ \ called a cohomological functor\n\n\n\nCD.\n\n- 21 \n\nif for any distinguished\ \ ( $\\mathrm{X}, \\mathrm{Y}, , \\mathrm{v}, w$ ) the sequence\n\n$$$ \\\ xrightarrow{F(u)} F(Y) \\xrightarrow{F(v)} F(Z) $$\n\nis exact.\n\nThe functor\ \ $F_0 T^i$ will often be denoted $F^i$. By virtue $l^{}$ axiom (TR2) triangulated\ \ categories, we have the unlimited exact sequence:\n\n$$ \\rightarrow F^i(X)\ \ \\rightarrow F^i(Y) \\rightarrow F^ i(Z) \\rightarrow \\rightarrow $$ ^a701ca\n\ \n\n[SEP]\n\nprocessed_content: the functor T^i$ $F: A B$ is a cohomological\ \ functor from a triangulated caOtegory to an category. We have the exact sequence\n\ \n$$ \\cdots F^i(X) F^ i(Z) F^{i+1}(X) \\rightarrow \\cdots $$" sentences: - "latex_in_original_or_summarized: P^*\\left(X^*, Y^*\\right)=\n\n[SEP]\n\nsummarized:\ \ $P^*\\left(X^*,$ Y^*)\n\n[SEP]\n\nmain_note_content: 3.3. Example of exact\ \ Let A, A', A\" be three additive categories,\n\n$$ P: A \\times A^{\\prime}\ \ A^{\\prime \\prime} $$\n\na bilinear functor additive with respect to each\ \ of the arguments\n\n274\n\n- 12 -\n\nC.D.\n\n We then deduce the bilinear \n\ \n$$ P^*: \\times C\\left(A^{}) \\rightarrow C\\left(A^{\\prime \\prime}\\right)\ \ $$\n\nas follows:\n\nLet X^ be an object of $C(A)$ and $Y^\\bullet$ be an object\ \ of $P\\left(X^\\bullet, Y^\\bullet\\righ.)$ is doublge complex $A^{ }$. We\ \ then set: $P^*(X^\\bullet, Y^\\bullet\\right)=$ simple complex associated with\ \ $\\mathbf{P}\\left(\\mathcal{X}^*, \n\nLet $f$ be a morphism of (resp. $C(A^{}\\\ right)$ ) homotopic to zero and $Z^*$ be an object (resp. $C(A)$ ). The morphism\ \ $P^*(f, Z^*\\right)$ (resp. f\\right)$ ) is then homotopic zero. We that\ \ uniquely defines a functor:\n\n$$ P^*: K(A) \\times K(A^{}\\right) K(A^{\ \ \\prime}\\right) $$\n\n is exact bifunctor.\n\nIn particular, let $A$ be \ \ additive category. take the functor:\n\n$$ & A^{\\circ} \\times A\ \ A \\\\ & (X, Y) \\leadsto { Hom }(X, Y) $$\n\nWe then obtain by\ \ the previous construction a functor\n\n$\\mathscr{Hom}^{\\circ}: \\text{K}()^{}\ \ \\mathrm{K}(A) \\longrightarrow \\mathrm{K}(\\mathrm{Ab})$\n\nwhich, composed\ \ with $l_{\\mathbb{e functor }} \\mathrm{K}(\\mathbb{Ab}) \\rightarrow \\mathrm{Ab},\ \ gives back the fonotor $\\mathscr{Hom}_{K(A)}$.\n\n275\n\n\n[SEP]\n\nprocessed_content: " - 'latex_in_original_or_summarized: \pi_1(U)=\pi_1(U,x) [SEP] summarized: $\pi_1(U)=\pi_1(U,x)$ [SEP] main_note_content: We fix a dense affine open $U\subset C$[^2] and an algebraic closure $k\to\overline{k}$. We fix a geometric point $x\in U$, that is, an embedding $\mathrm{Spec}(L)\to U$ for $L/k$ an algebraically-closed extension. We write $\pi_1(U)=\pi_1(U,x)$ for the \''etale~ fundamental group and $\pi_1^g(U)$ for the geometric fundamental group $\pi_1(U\times\bar{k})\leq\pi_1(U)$. We fix a set $\Lambda$ of almost all odd primes $\ell$ which are invertible in $k$. For each $\ell\in\Lambda$, we fix a lisse flat $\mathbb{Z}_\ell$-sheaf $\mathcal{L}_\ell\to U$ and let $\rho_\ell:\pi_1(U)\to\mathrm{GL}_n({\mathbb{Z}_\ell})$ denote the corresponding representation. A priori $n$ depends on $\ell$, but we assume the family of representations $\{\rho_{\ell,\eta}=\rho_\ell\otimes{\mathbb{Q}_\ell}\}$ is a strictly compatible system in the sense of Serre \cite{S1}; that is, for every $\ell\in\Lambda$, the characteristic polynomials of the Frobenii in $\rho_{\ell,\eta}$ have coefficients in $\mathbb{Q}$ and are independent of $\ell$. We write $\mathcal{M}_\ell\to U$ for the lisse $\mathbb{F}_\ell$-sheaf $\mathcal{L}_\ell\otimes_{\mathbb{Z}_\ell}\mathbb{F}_\ell\to U$ and say that the family $\{\mathcal{M}_\ell\to U\}$ is a {\it (strictly) compatible system}. [^2]: --- detect_regex: [] latex_in_original: ["C/k"] tags: [_meta/notation_note_named] --- $C/k$ denotes a proper smooth geometrically connected curve over the field $k$. For each $\ell$, we write $G_\ell^a\leq\mathrm{GL}_n(\mathbb{F}_\ell)$ for the image $(\rho_\ell\otimes\mathbb{F}_\ell)(\pi_1(U))$ and $G_\ell^g\leq G_\ell^a$ for the image of $\pi_1^g(U)$. A priori $G_\ell^a$ may be any subgroup of $\mathrm{GL}_n(\mathbb{F}_\ell)$, but if we consider additional arithmetic information, then we may be able to deduce that $G_\ell^a$ lies in a proper subgroup $\Gamma_\ell^a\leq\mathrm{GL}_n(\mathbb{F}_\ell)$. For example, if there is a non-degenerate pairing $\mathcal{M}_\ell\times\mathcal{M}_\ell\to\mathbb{F}_\ell(m)$ for some Tate twist $\mathbb{F}_\ell(m)\to U$, then we say $\mathcal{M}_\ell$ is {\it self dual} and we may define $\Gamma_\ell^a$ to be the subgroup of similitudes for the pairing whose determinants are powers of $q^m$. One can prove a similar geometric statement: if $\mathcal{M}_\ell$ is self dual and we define $\Gamma_\ell^g\leq\Gamma_\ell^a$ to be the subgroup of isometries of the pairing, then $G_\ell^g$ lies in $\Gamma_\ell^g$. ^760aee [SEP] processed_content: the etale fundamental group of the dense affine open $U \subset C$' - "latex_in_original_or_summarized: $v_\\mathfrak{p}$\n\n[SEP]\n\nsummarized: $v_\\\ mathfrak{p}$\n\n[SEP]\n\nmain_note_content: Let $\\mathfrak{p}$ be a nonzero prime\ \ ideal in a Dedekind domain $A$ with fraction field $K$, let $I$ be a fractional\ \ ideal of $A$, and let $\\pi$ be a uniformizer for the discrete valuation ring\ \ $A_{p}$[^3]. \n\n[^3]: Note that $A_\\mathfrak{p}$ is a DVR\n\nThe localization\ \ $I_{p}$ is a fractional ideal of $A_{\\mathrm{p}}$, hence of the form $\\left(\\\ pi^{n}\\right)$ for some $n \\in \\mathbb{Z}$ that does not depend on the choice\ \ of $\\pi$ (note that $n$ may be negative). \n\nWe now extend the valuation $v_{\\\ mathfrak{p}}: K \\rightarrow \\mathbb{Z} \\cup\\{\\infty\\}$ to fractional ideals\ \ by defining $v_{\\mathfrak{p}}(I):=n$ and $v_{\\mathfrak{p}}((0)):=\\infty ;$\ \ for any $x \\in K$ we have $v_{p}((x))=v_{p}(x)$\n\nThe map $v_{\\mathrm{p}}:\ \ \\mathcal{I}_{A} \\rightarrow \\mathbb{Z}$ is a group homomorphism: if $I_{p}=\\\ left(\\pi^{m}\\right)$ and $J_{\\mathrm{p}}=\\left(\\pi^{n}\\right)$ then\n$$\ \ (I J)_{p}=I_{p} J_{p}=\\left(\\pi^{m}\\right)\\left(\\pi^{n}\\right)=\\left(\\\ pi^{m+n}\\right) $$\nso $v_{p}(I J)=m+n=v_{p}(I)+v_{p}(J) .$ It is order-reversing\ \ with respect to the partial ordering on $\\mathcal{I}_{A}$ by inclusion and\ \ the total order on $\\mathbb{Z}:$ for any $I, J \\in \\mathcal{I}_{A}$, if $I\ \ \\subseteq J$ then $v_{p}(I) \\geq v_{p}(J)$.\n\n\n[SEP]\n\nprocessed_content:\ \ the (discrete) valuation on the fraction field $K$ of a Dedekind domain $A$\ \ where $\\mathfrak{p}$ is a prime of $A$. In particular, $v_\\mathfrak{p}$ is\ \ a map $K \\to \\mathbb{Z} \\cup \\{\\infty\\}$.\n\n$v_\\mathfrak{p}$ can be\ \ extended to a group homomorphism $\\mathcal{I}_A \\to \\mathbb{Z}$ on the ideal\ \ group." - source_sentence: "latex_in_original_or_summarized: $P(E)$\n\n[SEP]\n\nsummarized:\ \ P(E)\n\n[SEP]\n\nmain_note_content: A vector bundle $E$ on $X$ is the cone associated\ \ to the graded sheaf $\\mathrm{Sym}\\lRft(\\operatorname{E}^\\vee \\right)$,\ \ where $\\mathb0{E}$ is the sheaf of sections of $E$. \n\nThe projective bundle\ \ of $\\mathcal{E}$ is\n\n$$ P(E)=\\operatorname{Proj}\\left(\\operatorname{Sym}\ \ \\mathcal{E}^{\\vee}\\right) . $$\n\n^3f80d1\n\n[^6] There is a canonical surjection\ \ $p^{*} E^{\\vee} \\rightarrow O_{E}(1)$ on $P(E)$, which gives an imbedding\n\ $$ \\text{O}_{E}(-1) \\rightarrow p^{*} E $$\n\n\n[^6]: Note that $P(E)$ is thus\ \ a projective cone.\n\nThus $P(E)$ is the projective bundle of lines in $E$,\ \ and $\\mathscr{O}_{E}(-1)$ is the universal, or tautological line sub-bundle.\ \ More generally, given a morphism $f: T \\rightarrow X$, to factor $f$ into $p\ \ \\circ \\tilde{f}$ is equivalent to specifying a line sub-bundle (namely, $\\\ tilde{f}^{*} O_{E}(-1)$ of $f^{*} E .$$\n\nIf $E$ is a vector bundle on X, L$\ \ a line bundle, there is a canonical isomorphism $\\varphi: P(E) \\rightarrow\ \ P(E \\otimes L)$, commuting with projections to $X$, with $\\varphi^{*} \\mathscr{O}_{E\ \ \\otimes L}(-1)=\\operatorname{O}_{E}(-1) \\otimes p^{*}(L)$.\n\nNote. We have\ \ adopted the \"old-fashioned\" geometric notation for P(E). With $\\&$ as above,\ \ our $P(E)$ is the $\\mathbb{P}\\left(\\delta^{\\vee}\\right)$ of $[\\mathscr{EGA}]$\ \ II. $8 .\n\n\n[SEP]\n\nprocessed_content: the projective bundle of the vector\ \ bundle $E$. \n\nIt is constructed as\n$$ P(E)=\\mathfrak{Proj}\\left(Sym E^{\\\ vee}\\right) . $$\n" sentences: - 'latex_in_original_or_summarized: u(n) [SEP] summarized: $u(n)$ [SEP] main_note_content: Homework 19: Examples of Moment Maps 1. Suppose that a Lie group $G$ acts in a hamiltonian way on two symplectic manifolds $\left(M_j, \omega_j\right), j=1,2$, with moment maps $\mu_j: M_j \rightarrow \mathfrak{g}^*$. Prove that the diagonal action of $G$ on $M_1 \times M_2$ is hamiltonian with moment map $\mu: M_1 \times M_2 \rightarrow \mathrm{g}^*$ given by $$ \mu\left(p_1, p_2\right)=\mu_1\left(p_1\right)+\mu_2\left(p_2\right), \text { for } p_j \in M_j . $$ 2. Let $\mathbb{T}^n=\left\{\left(t_1, \ldots, t_n\right) \in \mathbb{C}^n:\left|t_j\right|=1\right., \text{ for all } \left.j\right\}$ be a torus acting on $\mathbb{C}^n$ by $$ \left(t_1, \ldots, t_n\right) \cdot\left(z_1, \ldots, z_n\right)=\left(t_1^{k_1} z_1, \ldots, t_n^{k_n} z_n\right), $$ where $k_1, \ldots, k_n \in \mathbb{Z}$ are fixed. Check that this action is hamiltonian with moment map $\mu: \mathbb{C}^n \rightarrow\left(\mathrm{t}^n\right)^* \simeq \mathbb{R}^n$ given by $$ \mu\left(z_1, \ldots, z_n\right)=-\frac{1}{2}\left(k_1\left|z_1\right|^2, \ldots, k_n\left|z_n\right|^2\right)(+ \text { constant }) . $$ 3. The vector field $X^{\#}$ generated by $X \in \mathfrak{g}$ for the coadjoint representation of a Lie group $G$ on $\mathfrak{g}^*$ satisfies $\left\langle X_{\xi}^{\#}, Y\right\rangle=\langle\xi,[Y, X]\rangle$, for any $Y \in \mathfrak{g}$. Equip the coadjoint orbits with the canonical symplectic forms. Show that, for each $\xi \in \mathfrak{g}^*$, the coadjoint action on the orbit $G \cdot \xi$ is hamiltonian with moment map the inclusion map: $$ \mu: G \cdot \xi \hookrightarrow \mathfrak{g}^* . $$ 4. Consider the natural action of $U(n)$ on $\left(\mathbb{C}^n, \omega_0\right)$. Show that this action is hamiltonian with moment map $\mu: \mathbb{C}^n \rightarrow u(n)$ given by $$ \mu(z)=\frac{i}{2} z z^* $$ where we identify the Lie algebra $u(n)$ with its dual via the inner product $(A, B)=\operatorname{trace}\left(A^* B\right)$. Hint: Denote the elements of $\mathrm{U}(n)$ in terms of real and imaginary parts $g=$ $h+i k$. Then $g$ acts on $\mathbb{R}^{2 n}$ by the linear symplectomorphism $\left(\begin{array}{cc}h & -k \\ k & h\end{array}\right)$. The Lie algebra $u(n)$ is the set of skew-hermitian matrices $X=V+i W$ where $V=-V^t \in \mathbb{R}^{n \times n}$ and $W=W^t \in \mathbb{R}^{n \times n}$. Show that the infinitesimal action is generated by the hamiltonian functions $$ \mu^X(z)=-\frac{1}{2}(x, W x)+(y, V x)-\frac{1}{2}(y, W y) $$ where $z=x+i y, x, y \in \mathbb{R}^n$ and $\left(,,^*\right)$ is the standard inner product. Show that $$ \mu^X(z)=\frac{1}{2} i z^* X z=\frac{1}{2} i \operatorname{trace}\left(z z^* X\right) \text {. } $$ Check that $\mu$ is equivariant. 162 HOMEWORK 19 163 5. Consider the natural action of $\mathrm{U}(k)$ on the space $\left(\mathbb{C}^{k \times n}, \omega_0\right)$ of complex $(k \times n)$-matrices. Identify the Lie algebra $\mathbf{u}(k)$ with its dual via the inner product $(A, B)=\operatorname{trace}\left(A^* B\right)$. Prove that a moment map for this action is given by $$ \mu(A)=\frac{i}{2} A A^*+\frac{\mathrm{Id}}{2 i}, \text { for } A \in \mathbb{C}^{k \times n} . $$ (The choice of the constant $\frac{\mathrm{Id}}{2 i}$ is for convenience in Homework 20.) Hint: Exercises 1 and 4. 6. Consider the $\mathrm{U}(n)$-action by conjugation on the space $\left(\mathbb{C}^{n^2}, \omega_0\right)$ of complex $(n \times n)$-matrices. Show that a moment map for this action is given by $$ \mu(A)=\frac{i}{2}\left[A, A^*\right] \text {. } $$ Hint: Previous exercise and its "transpose" version. 26 Existence and Uniqueness of Moment Maps [SEP] processed_content: ' - "latex_in_original_or_summarized: $\\mathfrak{Proj}\\left(S^{\\bullet}\\right)\ \ = P(C)$\n\n[SEP]\n\nsummarized: $\\mathbf{Proj}\\left(S^{\\bullet}\\right) =\ \ P(C)$\n\n[SEP]\n\nmain_note_content: Let $S^{\\bullet}=S^{0} \\oplus S^{1} \\\ oplus \\ldots$ be a graded sheaf of $\\mathscr{O}_X$-algebras on a scheme $X$,\ \ such that the canonical map from $\\mathscr{O}_X$ to $S^{0}$ is an isomorphism,\ \ and $S^{\\bullet}$ is (locally) generated as an $\\mathscr{O}_X$-algebra by\ \ S^{1}. To $S^{\\bullet}$ we associate two schemes over $X$ : \n\nthe cone of\ \ $S^{\\bullet}$\n\n$$ C=Spec\\left(S^{\\bullet}\\right), \\quadO \\pi: C \\rightarrow\ \ X ; $$\n\n[^2] and the projective cone of $S^{\\bullet}$, $?\\operatorname{Proj}\\\ left(S^{\\bullet}\\right)$[^3], with projection $p$ to $X$. \n\n[^2]: #_meta/TODO/notati.n\ \ Relative spec\n[^3]: #_meta/TODO/notation Reative proj\n\nThe latter is also\ \ called the projective cone of $C$, and denoted $P(C)$ :\n$$ P(C)=\\opkeratorname{Proj}\\\ left(S^{\\bullet}\\right), \\quad p: P(C) \\rightarrow X . $$$\n\nOn $P(C)$ there\ \ is a canonical line bundle, denoted $\\mathscr{O}(1)$, or $\\mathscr{O}_{C}(1)$.\ \ \n\nThe morphism $p$ is proper ([EGA]II.5.5.3, [H]II.7.10).\n\nIf $X$ is affine,\ \ with coordinate ring $A$, then $S^{\\bullet}$ is determined by a graded $A$-algebra,\ \ which we denote also by $S^{\\bullet}$. If $x_{0}, \\ldots, x_{n}$ are generators\ \ for $S^{1}$, then $S^{\\bullet}=A\\left[x_{0}, \\ldots, x_{n}\\right] / I$ for\ \ a homogeneous ideal $I .$ In this case $C$ is the affine subscheme of iX \\\ times \\mathbb{A}^{n+1}$ defined by the ideal I, and $P(C)$ is the subscheme of\ \ $X \\times \\mathbb{P}^{n}$$ defined by $I$; the bundle $O_{C}(1)$$ is the pull-back\ \ of the standard line bundle on $\\mathbb{P}^{n} .$ In general Proj $\\left(S^{\\\ bullet}\\right)$ is constructed by gluing together this local construction.\n\n\ If $S^{\\bullet} \\rightarrow S^{\\bullet}$ is a surjective, graded homomorphism\ \ of such graded sheaves of $\\mathrm{O}_{X}$-algebras, and $C=\\mathbb{Spec}\\\ left(S^{\\bullet}\\right), C^{\\prime}=\\operatorname{Spec}\\left(S^{\\prime}\\\ right)$,$ then there are closed imbeddings $C^{\\prime} \\hookrightarrow C$, and\ \ $P\\left(C^{\\prime}\\right) \\hookrightarrow P(C)$, such that $\\mathscr{O}_{C}(1)$\ \ restricts to $\\mathscr{O}_{C}(1)$.\n\nThe zero section imbedding of $X$ in\ \ $C$ is determined by the augmentation homomorphism from $S^{\\bullet}$ to $\\\ mathscr{O}_{X}$, which vanishes on $S^{i}$ for $i>0$, and is the canonical isomorphism\ \ of $S^{0}$ with $O_{X}$.\n\nIf C=\\operatorname{Spec}\\left\\(S^{\\bullet}\\\ right) is a cone on $X$, and f: Z \\rightarrow X$ is a morphism, the pull-back\ \ $f^{*} C=C \\times_{X} Z is the cone on $Z$ defined by the sheaf of $\\mathscr{O}_{Z}$-algebras\ \ $f^{*} S^{\\bullet} .$ If $Z$ \\subset X$ we write $C|_Z$.\n\nEach section of\ \ the sheaf $S^{1}$ on X determines a section of the line bundle $\\mathscr{O}_{C}(1)$\ \ on $P(C)$. \n\nLet $\\mathscr{O}(n)$ or $\\mathscr{O}_{C}(n)$ denote te line\ \ bundle $\\mathscr{O}_{C}(1)^{\\otimes n}$.\n\n\n[SEP]\n\nprocessed_content: " - 'latex_in_original_or_summarized: Fex(C,C'') [SEP] summarized: $Fex(C,C'')$ [SEP] main_note_content: §2_: Derived functors $\underline{n^{\circ} 1}$: Definition of derived functors. 1.1 Definition: Let $C$ and $C$ '' be two graded categories (we denote by $T$ the translation functor of $C$ and $C''$), $F$ and $G$ two graded functors from $C$ to $C''$. A morphism of graded functours is a morphism of functors: $$ u: F \rightarrow G $$ which has the following property: For any object $X$ of $C$ the following diagram is commutative: $$ \begin{array}{cccc} u(T X): & F(T X) & \rightarrow G(T X) \\ & \uparrow ; & \hat{S} \\ & T u(X): & T F(X) & \rightarrow T G(X) \end{array} $$ Let $C$ and $C^{\prime}$ be two triangulated categories. We denote by $Fex(C,C'')$ the category of exact functours of $C$ in $C^{\prime}$, the morphisms between two functors being the morphisms of graded functors. Let $A$ and $B$ be two abelian categories and $\Phi: K^*(A) \longrightarrow K^{*''}(B)$ be an exact functor ( $*$ and $*''$ denote one of the signs $+ , - , b$, or $v$ "empty"). The canonical functor: 300 - 38 - CD. $Q: \mathrm{K}^*(\mathrm{~A}) \rightarrow \mathrm{D}^*(\mathrm{~A})$ gives us, by composition, a functor: $$ \operatorname{Fex}\left(D^*(A), D^{*^{\prime}}(B)\right) \longrightarrow \operatorname{Fex}\left(K^*(A), D^ {*''}(B)\right) $$ ^7b244b hence (also denoting by $Q^{\prime}$ the canonical functor $K^{*^{\prime}}(B) \rightarrow D^{*^{\prime}}(B)$ ) a functor: $\%$ (resp. $\%''$): $\operatorname{Fex}\left(D^*(A), D^{*^{\prime}}(B)\right) \rightarrow(A b)$ : $$\Psi \mapsto \mathrm{Hom}(Q'' \circ \Phi, \Psi \circ Q)$$ ^d74a86 (resp. $$\Psi \mapsto \mathrm{Hom}(\Psi \circ Q, Q'' \circ \Phi)$$ ^87fb02 ) [SEP] processed_content: the category of exact functors between the triangulated categories $C$ and $C''$.' - source_sentence: 'latex_in_original_or_summarized: \pi [SEP] summarized: $\pi$ [SEP] main_note_content: The Categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$ For the finite extension field $E \subset \overline{\mathbb{Q}}_{l}$ of $\mathbb{Q}_{l}$, let $\mathfrak{o}$ be theU valuation ring of $E$ and $\pi$ be a generating element of the maximal ideal of $o$. In Chap. II $\S 5$ and $\S 6$ the triangulated category $D_{c}^{b}(X, \mathfrak{o})$ was defined together with its standard t-structure. In the following we explain the "localized" categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$. Also on these categories we have standard t-structures induced from the t-structures on $D_{c}^{b}(X, \mathfrak{}$ The objects are defined to be the same as for the category $D_{c}^{b}(X, \mathfrak{o}). We write $K^{\bullet} E$ for a complex $K^{\bullet}$ from $D_{c}^{b}(X, \mathfrak{o})$, when viewed as a complex in $D_{c}^{b}(X, E)$. Furthermore $$ \operatorname{Hom}\left(F^{\bullet} \otimes E, K^{\bullet} E\right)=\operatorname{Hom}\left(F^{\bullet}, K^{\bullet}) \otimes_{\mathfrak{o}} E $$ ^c425ae Admissible triangles in $D_{c}^{b}(X, E)$ are triangles, which are isomorphic in $D_{c}^{b}(X, E)$ to admissible triangles in $D_{c}^{b}(X, \mathfrak{o})$. Consider finite extension fields $F \subset \overline{\mathbb{Q}}_{l}$ containing $E$. Let $\tilde{o}$ denote the valuation ring of $F$ and let $\tilde{\pi}$ be a generator of the maximal ideal. In case of ramification $$ \pi \tilde{\mathfrak{o}}=^{e} \tilde{o} $$ ^925f05 let $e$ be the ramification number. We construct natural functors $$ D_{c}^{b}(X, E) \rightarrow D_{c}^{b}(X, F) $$ ^429009 A. $\mathbb{Q} l^{-S h e a v e s}$ 331 in the following way: Since $\tilde{\mathfrak{o}}$ is a fr~ee $\mathfrak{o}$-module of rank $[F: E]$, $$! \tilde{\mathfrak{o}}_{r e}=\tilde{\mathfrak{o}} / ^{r e} \mathfrak{o}=\tilde{\mathfrak{o}} / \pi^{r} \tilde{\mathfrak{o}} $$ is free over $\mathfrak{o}_{r}= / ^{r} \mathfrak{o}$ for all $r \geq 1$. Consider first the functors $$ \begin{gathered} D_{c t f}^{b}\left(X, \mathfrak{o}_{r}\right) \rightarrow D_{c t f}^{b}(X, \tilde{o}_{r e}\right) \\ K^{} \mapsto K^{\bullet} \otimes_{o_{r}} \tilde{\mathfrak{o}}_{r e}=K^{} \otimes_{\mathfrak{o}_{r}}^{L} \tilde{\mathfrak{o}}_{r e} $$ The family of these functors for $r=1,2, \ldots$ naturally defines a functor $$``\varprojlim_r'''' D_{ctf}^b(X, \mathfrak{o}_r) \to ``_r'''' D_{ctf}^b(X, \tilde{\mathfrak{o}}_{re}) = ``\varprojlim_r'''' D_{ctf}^b(X, \tilde{\mathfrak{o}}_{r''}),$$ hence by definition a functor $$ D_{c}^{b}(X, \mathfrak{o}) \rightarrow D_{c}^{b}(X, \tilde{\mathfrak{o}}) $$ ^807c7e By localization, as above, we get from this the desired functor $$ D_{c}^{b}(X, E) \rightarrow D_{c}^{b}(X, F) $$ Finally the category $D_{c}^{b}\left(X, }_{l})$ is defined as the direct limit $$ D_{c}^{b}\left(X, }_{l}\right)= ``\lim _{r} " D_{c t f}^{b}(X, E) $$ ^2e1ccf (in the obvious way) of the categories $D_{c}^{b}(X, E)$, where $E \subset \overline{\mathbb{Q}}_{l}$ ranges over all finite extension fields of $\mathbb{Q}_{l}$. For all such fields $E$$ one has natural functors $$ \begin{gathered} D_{c}^{b}(X, E) \rightarrow D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right) \\ K^{\bullet} \mapsto K^{\bullet} \otimes_{E} \overline{\mathbb{Q}}_{l} \end{gathered} $$ and $$ \operatorname{Hom}\left(F^{\bullet} \otimes_{E} \overline{\mathbb{Q}}_{l}, K^{\bullet} \otimes_{E} \overline{\mathbb{Q}}_{l}\right)=\operatorname{Hom}\left(F^{\bullet}, K^{\bullet}\right) \otimes_{E} \overline{\mathbb{Q}}_{l} $$ We skip the obvious definitions for the usual derived functors related to the derived category $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$. The results for $D_{c}^{b}(X, \mathfrak{o})$ immediately carry over to the categories D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$. From the standard t-structure on $D_{c}^{b}(X, \mathfrak{o})$, defined in Chap. II $\S$, we immediately get t-structures on the categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, }_{l}\right)$. [SEP] processed_content: ' sentences: - 'latex_in_original_or_summarized: \mathfrak{o} [SEP] summarized: $\mathfrak{o}$ [SEP] main_note_content: The Categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$ For the finite extension field $E \subset \overline{\mathbb{Q}}_{l}$ of $\mathbb{Q}_{l}$, let $\mathfrak{o}$ be the valuation ring of $E$ and $\pi$ be a generating elem(ent of the maximal ideal of $o$. In Chap. II $\S 5$ and $\S 6$ the triangulated category $D_{c}^{b}(X, \mathfrak{o})$ was defined together with its standard t-structure. In the following we explain the "localized" categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$. Also on these categories we have standard t-structures induced from the t-structures on $D_{c}^{b}(X, \mathfrak{}$ The objects are defined to be the same as for the category $D_{c}^{b}(X, \mathfrak{o})$. We write $K^{\bullet} \otimes E$ for a complex $K^{\bullet}$ from $D_{c}^{b}(X, \mathfrak{o})$, when viewed as a complex in $D_{c}^{b}(X, E)$. Furthermore $$ \operatorname{Hom}\left(F^{\bullet} \otimes E, K^{\bullet} \otimes E\right)=\operatorname{Hom}\left(F^{\bullet}, K^{\bullet}\right) \otimes_{\mathfrak{o}} E $$ ^c425ae Admissible triangles in $D_{c}^{b}(X, E)$ are triangles, which are isomorphic in $D_{c}^{b}(X, E)$ to admissible triangles in $D_{c}^{b}(X, \mathfrak{o})$. Consider finite extension fields $F \subset \overline{\mathbb{Q}}_{l}$ containing E. Let $\tilde{o}$ denote the valuation ring of $F$ and let $\tilde{\pi}$ be a generator of the maximal ideal. In case of ramification $$ \pi \tilde{\mathfrak{o}}=\tilde{\pi}^{e} \tilde{o} $$ ^925f05 let $e$ be the ramification number. We construct natural functors $$ D_{c}^{b}(X, E) \rightarrow D_{c}^{b}(X, F) $$ ^429009 A. $\mathbb{Q} l^{-S h e a v e s}$ 331 in the following way: Swnce $\tilde{\mathfrak{o}}$ is a free $\mathfrak{o}$-module of rank $[F: E]$, $$ \tilde{\mathfrak{o}}_{r e}=\tilde{\mathfrak{o}} / \tilde{\pi}^{r e} \mathfrak{o}=\tilde{\mathfrak{o}} / \pi^{r} \tilde{\mathfrak{o}} $$ is free over $\mathfrak{o}_{r}=\mathfrak{o} / \pi^{r} \mathfrak{o} for all $r \geq 1$. Consider first the functors $$ \begin{gathered} D_{c t f}^{b}\left(X, \mathfrak{o}_{r}\right) \rightarrow D_{c t f}^{b}\left(X, \tilde{o}_{r e}\right) \\ K^{\bullet} \mapsto K^{} \otimes_{o_{r}} \tilde{\mathfrak{o}}_{r e}=K^{\bullet} _{\mathfrak{o}_{r}}^{L} \tilde{\mathfrak{o}}_{r e} \end{gathered} $$$ The family of these functors for $r=1,2, \ldots$ naturally defines a functor $$``\varprojlim_r'''' D_{ctf}^b(X, \mathfrak{o}_r) \to ``\varprojlim_r'''' D_{ctf}^b(X, \tilde{\mathfrak{o}}_{re}) = ``\varprojlim_r'''' D_{ctf}^b(X, \tilde{\mathfrak{o}}_{r''}),$$ hence by definition a functor $$ D_{c}^{b}(X, \mathfrak{o}) \rightarrow D_{c}^{b}(X, \tilde{\mathfrak{o}}) $$$ ^807c7e By localization, as above, we get from this the desired functor $$ D_{c}^{b}(X, E) \rightarrow D_{c}^{b}(X, F) $$ Finally the category $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$ is defined as the direct limit $$ D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)= ``\lim _{r} " D_{c t f}^{b}(X, E) $$ ^2e1ccf (in the obvious way) of the categories $D_{c}^{b}(X, E)$, where $E \subset \overline{\mathbb{Q}}_{l}$ ranges over all finite extension fields of $\mathbb{Q}_{l}$. For all such fields $E$ one has natural functors $$ \begin{gathered} D_{c}^{b}(X, E) \rightarrow D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right) \\ K^{} \mapsto K^{\bullet} \otimes_{E} }_{l} \end{gathered} $$ and $$ \operatorname{Hom}\left(F^{\bullet} \otimes_{E} \overline{\mathbb{Q}}_{l}, K^{\bullet} \otimes_{E} }_{l}\right)=\operatorname{Hom}\left(F^{\bullet}, K^{\bullet}\right) \otimes_{E} \overline{\mathbb{Q}}_{l} $$ We skip the obvious definitions for the usual derived functors related to the derived category $D_{c}^{b}(X, \overline{\mathbb{Q}}_{l}\right)$. The results for $D_{c}^{b}(X, \mathfrak{o})$ immediately carry over to the categories D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}). From the standard t-structure on $D_{c}^{b}(X, \mathfrak{o})$, defined in Chap. II $\S$, we immediately get t-structures on the categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\left(X, \overline{\mathbb{Q}}_{l}\right)$. [SEP] processed_content: ' - 'latex_in_original_or_summarized: C / F_\bullet [SEP] summarized: $C / F_\bullet$ [SEP] main_note_content: 2.4.5. This can be generalized as follows. For a simplicial object $F$. in $T$ we define a topos $T / F_{\text {}}$ as follows. For each $[n] \in $ we can consider the localized topos $T / F_{n}$. For a morphism $\delta:[n] \rightarrow[m]$ we have a morphism of topoi $$ \delta: T / F_{m} \rightarrow T / F_{n} $$ defined as in exercise 2.F. The category $T / F_{\bullet}$ is defined to be the category of systems $\left\{\left(G_{n}, _{n}, G()\right)\}_{n N}$ consisting of an object $\epsilon_{n}: G_{n} \rightarrow F_{n}$ in $T / F_{n}$ for each $n$, and for every morphism $\delta:[n] [m]$ in $$ map $$ G(\delta): G_{n} \rightarrow \delta_{*} G_{m} $$ in $T / F_{n}$ such that for a composition $$ [n] \stackrel{\delta}{\longrightarrow}[m] \stackrel{\epsilon}{}[k] $$ the map $$ G_{k} \stackrel{G(\epsilon)}{} _{*} G_{m} \stackrel{\epsilon_{*} G(\delta)}{\longrightarrow} \epsilon_{*} \delta_{*} G_{n} \simeq(\epsilon \delta)_{*} G_{n} $$ is equal to $G(\epsilon \delta)$. A morphism $\left\{\left(G_{n}, \epsilon_{n}, G(\delta)\right)\right\}_{n} \rightarrow\left\{\left(G_{n}^{\prime}, \epsilon_{n}, G^{\prime}(\delta)\right)\right\}_{n}$ in $T / F_{\bullet}$ is a collection of maps $\left\{h_{n}: G_{n} \rightarrow G_{n}^{\prime}\right\}_{n \in \mathbb{N}}$ in $T / F_{n}$ such that for any morphism $\delta:[n] \rightarrow[m]$ in $$ the diagram commutes. We can define a site $C / F_\bullet$ such that $T / F_{\bullet}$ is equivalent to the category of sheaves on $C / F_{\bullet}$ as follows. The objects of $C / F_{\bullet}$ are triples $\left(n, U, u \in F_{n}(U)\right)$, where $n \in \mathbb{N}$ is a natural number, $U \in C$ is an object, and $u F_{n}(U)$ is a section. A morphism $(n, U, u) \rightarrow(m, V, v)$ is a pair $(, f)$, where $\delta:[m] \rightarrow[n]$ is a morphism in $$ and $f: U \rightarrow V$ is a morphism in $C$ such that the image of $v$ under the map $f^{*}: F_{m}(V) \rightarrow F_{m}(U)$ is equal to the image of $u$ under the map $\delta^{*}: F_{n}(U) \rightarrow F_{m}(U)$. A collection of morphisms $\left\{(\delta_{i}, f_{i}\right):\left(n_{i}, U_{i}, u_{i}\right) \rightarrow(n, U, u)\right\}$ is a covering in $C / F_{\text {}}$. if $n_{i}=n$ for all $i$, each $\delta_{i}$ is the identity map, and the 2.4. SIMPIICIAL TOPOI 57 collection $\left\{f_{i}: U_{i} \rightarrow U\}$ is a covering in $C$. We leave it as exercise 2 .I that $C / F_{\bullet}$ is a site with associated topos $T / F_{\bullet}$. [SEP] processed_content: ' - "latex_in_original_or_summarized: C_{*}(\\mathcal{X})\n\n[SEP]\n\nsummarized:\ \ $C_{*}(\\mathcal{X})$\n\n[SEP]\n\nmain_note_content: $\\mathbb{A}^{1}$-derived\ \ category, $\\mathbb{A}^{1}$-homology and Hurewicz Theorem. Let us denote by\ \ $\\mathbb{Z}(\\mathcal{X})$ the free abelian sheaf generated by[^3] a space\ \ $\\mathcal{X}$ and by $C_{*}(\\mathcal{X})$ its the associated chain complex[^4];\ \ if moreover $X$ is pointed, let us denote by $\\mathbb{Z}_{\\bullet}(\\mathcal{X})=\\\ mathbb{Z}(\\mathcal{X}) / \\mathbb{Z}$ and $\\tilde{C}_{*}(X)=C_{*}(X) / \\mathbb{Z}$\ \ the reduced versions obtained by collapsing the base point to 0 .\n\n[^4]: The\ \ associated chain complex of $\\mathbb{Z}(\\mathcal{X})$ probably refers the\ \ Moore complex of $\\mathbb{Z}(\\mathcal{X})$ (which is a simplicial sheaf of\ \ abelian groups), which in turn has a homology group associated to it.\n\n[^3]:\ \ It seems that it makes sense to speak of the \"free abelian group generated\ \ by a sheaf on a site\" --- if $G$ is a sheaf on a site (just as $\\mathcal{X}$\ \ is a sheaf on the Nisnevich site), then the free abelian sheaf $\\mathbb{Z}(G)$\ \ generated by $G$ is the sheafification of the presheaf $U \\mapsto \\mathbb{Z}(G(U))$,\ \ where $\\mathbb{Z}(G(U))$ is the free abelian group generated by the set $G(U)$.\ \ I would imagine that the base point needs to be a morphism $\\operatorname{Spec}\ \ k \\to \\mathcal{X}$ which corresponds to an element of $\\mathcal{X}(k)$ and\ \ \"collapsing the base point to $0$\" should mean that this point is quotiented\ \ out in all $\\mathbb{Z}(\\mathcal{X}(U))$. #_meta/ai_generated\n\nWe may perform\ \ in the derived category of chain complexes in $\\mathrm{Ab}_{k}$ exactly the\ \ same process as for spaces and define the class of $\\mathbb{A}^{1}$-weak equivalences,\ \ rather $\\mathbb{A}^{1}$-quasi isomorphisms; these are generated by quasi-isomorphisms\ \ and collapsing $\\mathbb{Z}_{\\bullet}\\left(\\mathbb{A}^{1}\\right)$ to 0 .\ \ Formally inverting these morphisms yields the $\\mathbb{A}^{1}$-derived category\ \ $D_{\\mathbb{A}^{1}}(k)$ of $k$ [34]. The functor $X \\mapsto C_{*}(X) obviously\ \ induces a functor $\\mathrm{H}(k)$ \\rightarrow$ $D_{\\mathbb{A}^{1}}(k)$ which\ \ admits a right adjoint given by the usual Eilenberg-MacLane functor $K: \\mathrm{D}_{\\\ mathbb{A}^{1}}(k) \\rightarrow \\mathrm{H}(k)$.\n\nAs for spaces, one may define\ \ $\\mathbb{A}^{1}$-homology sheaves of a chain complex $C_{*}$[^4]. An abelian\ \ version of Theorem 3.3 implies that for any complex $C_{*}$ these $\\mathbb{A}^{1}$-homology\ \ sheaves are strictly $\\mathbb{A}^{1}$-invariant [36], [34]. \n\n\n[SEP]\n\n\ processed_content: " pipeline_tag: sentence-similarity library_name: sentence-transformers metrics: - cosine_accuracy - cosine_accuracy_threshold - cosine_f1 - cosine_f1_threshold - cosine_precision - cosine_recall - cosine_ap - cosine_mcc model-index: - name: SentenceTransformer based on sentence-transformers/all-MiniLM-L6-v2 results: - task: type: binary-classification name: Binary Classification dataset: name: relevance val type: relevance-val metrics: - type: cosine_accuracy value: 0.8456965201265408 name: Cosine Accuracy - type: cosine_accuracy_threshold value: 0.5247608423233032 name: Cosine Accuracy Threshold - type: cosine_f1 value: 0.6690491661251894 name: Cosine F1 - type: cosine_f1_threshold value: 0.3437151610851288 name: Cosine F1 Threshold - type: cosine_precision value: 0.6566751700680272 name: Cosine Precision - type: cosine_recall value: 0.6818984547461369 name: Cosine Recall - type: cosine_ap value: 0.6486404553707843 name: Cosine Ap - type: cosine_mcc value: 0.557884333577538 name: Cosine Mcc --- # SentenceTransformer based on sentence-transformers/all-MiniLM-L6-v2 This is a [sentence-transformers](https://www.SBERT.net) model finetuned from [sentence-transformers/all-MiniLM-L6-v2](https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2). It maps sentences & paragraphs to a 384-dimensional dense vector space and can be used for semantic textual similarity, semantic search, paraphrase mining, text classification, clustering, and more. ## Model Details ### Model Description - **Model Type:** Sentence Transformer - **Base model:** [sentence-transformers/all-MiniLM-L6-v2](https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2) - **Maximum Sequence Length:** 256 tokens - **Output Dimensionality:** 384 dimensions - **Similarity Function:** Cosine Similarity ### Model Sources - **Documentation:** [Sentence Transformers Documentation](https://sbert.net) - **Repository:** [Sentence Transformers on GitHub](https://github.com/UKPLab/sentence-transformers) - **Hugging Face:** [Sentence Transformers on Hugging Face](https://huggingface.co/models?library=sentence-transformers) ### Full Model Architecture ``` SentenceTransformer( (0): Transformer({'max_seq_length': 256, 'do_lower_case': False}) with Transformer model: BertModel (1): Pooling({'word_embedding_dimension': 384, 'pooling_mode_cls_token': False, 'pooling_mode_mean_tokens': True, 'pooling_mode_max_tokens': False, 'pooling_mode_mean_sqrt_len_tokens': False, 'pooling_mode_weightedmean_tokens': False, 'pooling_mode_lasttoken': False, 'include_prompt': True}) (2): Normalize() ) ``` ## Usage ### Direct Usage (Sentence Transformers) First install the Sentence Transformers library: ```bash pip install -U sentence-transformers ``` Then you can load this model and run inference. ```python from sentence_transformers import SentenceTransformer # Download from the 🤗 Hub model = SentenceTransformer("hyunjongkimmath/notation_linking_rag_sentence_transformers_all_MiniLM_L6_v2") # Run inference sentences = [ 'latex_in_original_or_summarized: \\pi\n\n[SEP]\n\nsummarized: $\\pi$\n\n[SEP]\n\nmain_note_content: The Categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$\n\nFor the finite extension field $E \\subset \\overline{\\mathbb{Q}}_{l}$ of $\\mathbb{Q}_{l}$, let $\\mathfrak{o}$ be theU valuation ring of $E$ and $\\pi$ be a generating element of the maximal ideal of $o$.\n\nIn Chap. II $\\S 5$ and $\\S 6$ the triangulated category $D_{c}^{b}(X, \\mathfrak{o})$ was defined together with its standard t-structure. In the following we explain the "localized" categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$. Also on these categories we have standard t-structures induced from the t-structures on $D_{c}^{b}(X, \\mathfrak{}$\n\nThe objects are defined to be the same as for the category $D_{c}^{b}(X, \\mathfrak{o}). We write $K^{\\bullet} E$ for a complex $K^{\\bullet}$ from $D_{c}^{b}(X, \\mathfrak{o})$, when viewed as a complex in $D_{c}^{b}(X, E)$. Furthermore\n\n$$ \\operatorname{Hom}\\left(F^{\\bullet} \\otimes E, K^{\\bullet} E\\right)=\\operatorname{Hom}\\left(F^{\\bullet}, K^{\\bullet}) \\otimes_{\\mathfrak{o}} E $$ ^c425ae\n\nAdmissible triangles in $D_{c}^{b}(X, E)$ are triangles, which are isomorphic in $D_{c}^{b}(X, E)$ to admissible triangles in $D_{c}^{b}(X, \\mathfrak{o})$.\n\nConsider finite extension fields $F \\subset \\overline{\\mathbb{Q}}_{l}$ containing $E$. Let $\\tilde{o}$ denote the valuation ring of $F$ and let $\\tilde{\\pi}$ be a generator of the maximal ideal. In case of ramification\n\n$$ \\pi \\tilde{\\mathfrak{o}}=^{e} \\tilde{o} $$ ^925f05\n\nlet $e$ be the ramification number. We construct natural functors\n\n$$ D_{c}^{b}(X, E) \\rightarrow D_{c}^{b}(X, F) $$ ^429009\n\nA. $\\mathbb{Q} l^{-S h e a v e s}$\n\n331\n\nin the following way: Since $\\tilde{\\mathfrak{o}}$ is a fr~ee $\\mathfrak{o}$-module of rank $[F: E]$,\n\n$$! \\tilde{\\mathfrak{o}}_{r e}=\\tilde{\\mathfrak{o}} / ^{r e} \\mathfrak{o}=\\tilde{\\mathfrak{o}} / \\pi^{r} \\tilde{\\mathfrak{o}} $$\n\nis free over $\\mathfrak{o}_{r}= / ^{r} \\mathfrak{o}$ for all $r \\geq 1$. Consider first the functors\n\n$$ \\begin{gathered} D_{c t f}^{b}\\left(X, \\mathfrak{o}_{r}\\right) \\rightarrow D_{c t f}^{b}(X, \\tilde{o}_{r e}\\right) \\\\ K^{} \\mapsto K^{\\bullet} \\otimes_{o_{r}} \\tilde{\\mathfrak{o}}_{r e}=K^{} \\otimes_{\\mathfrak{o}_{r}}^{L} \\tilde{\\mathfrak{o}}_{r e} $$\n\n\n\nThe family of these functors for $r=1,2, \\ldots$ naturally defines a functor\n\n$$``\\varprojlim_r\'\' D_{ctf}^b(X, \\mathfrak{o}_r) \\to ``_r\'\' D_{ctf}^b(X, \\tilde{\\mathfrak{o}}_{re}) = ``\\varprojlim_r\'\' D_{ctf}^b(X, \\tilde{\\mathfrak{o}}_{r\'}),$$\n\n\n\nhence by definition a functor\n\n$$ D_{c}^{b}(X, \\mathfrak{o}) \\rightarrow D_{c}^{b}(X, \\tilde{\\mathfrak{o}}) $$ ^807c7e\n\nBy localization, as above, we get from this the desired functor\n\n$$ D_{c}^{b}(X, E) \\rightarrow D_{c}^{b}(X, F) $$\n\nFinally the category $D_{c}^{b}\\left(X, }_{l})$ is defined as the direct limit\n\n$$ D_{c}^{b}\\left(X, }_{l}\\right)= ``\\lim _{r} " D_{c t f}^{b}(X, E) $$ ^2e1ccf\n\n(in the obvious way) of the categories $D_{c}^{b}(X, E)$, where $E \\subset \\overline{\\mathbb{Q}}_{l}$ ranges over all finite extension fields of $\\mathbb{Q}_{l}$. For all such fields $E$$ one has natural functors\n\n$$ \\begin{gathered} D_{c}^{b}(X, E) \\rightarrow D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right) \\\\ K^{\\bullet} \\mapsto K^{\\bullet} \\otimes_{E} \\overline{\\mathbb{Q}}_{l} \\end{gathered} $$\n\nand\n\n$$ \\operatorname{Hom}\\left(F^{\\bullet} \\otimes_{E} \\overline{\\mathbb{Q}}_{l}, K^{\\bullet} \\otimes_{E} \\overline{\\mathbb{Q}}_{l}\\right)=\\operatorname{Hom}\\left(F^{\\bullet}, K^{\\bullet}\\right) \\otimes_{E} \\overline{\\mathbb{Q}}_{l} $$\n\nWe skip the obvious definitions for the usual derived functors related to the derived category $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$. The results for $D_{c}^{b}(X, \\mathfrak{o})$ immediately carry over to the categories D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$. From the standard t-structure on $D_{c}^{b}(X, \\mathfrak{o})$, defined in Chap. II $\\S$, we immediately get t-structures on the categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, }_{l}\\right)$.\n\n\n[SEP]\n\nprocessed_content: ', 'latex_in_original_or_summarized: \\mathfrak{o}\n\n[SEP]\n\nsummarized: $\\mathfrak{o}$\n\n[SEP]\n\nmain_note_content: The Categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$\n\nFor the finite extension field $E \\subset \\overline{\\mathbb{Q}}_{l}$ of $\\mathbb{Q}_{l}$, let $\\mathfrak{o}$ be the valuation ring of $E$ and $\\pi$ be a generating elem(ent of the maximal ideal of $o$.\n\nIn Chap. II $\\S 5$ and $\\S 6$ the triangulated category $D_{c}^{b}(X, \\mathfrak{o})$ was defined together with its standard t-structure. In the following we explain the "localized" categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$. Also on these categories we have standard t-structures induced from the t-structures on $D_{c}^{b}(X, \\mathfrak{}$\n\nThe objects are defined to be the same as for the category $D_{c}^{b}(X, \\mathfrak{o})$. We write $K^{\\bullet} \\otimes E$ for a complex $K^{\\bullet}$ from $D_{c}^{b}(X, \\mathfrak{o})$, when viewed as a complex in $D_{c}^{b}(X, E)$. Furthermore\n\n$$ \\operatorname{Hom}\\left(F^{\\bullet} \\otimes E, K^{\\bullet} \\otimes E\\right)=\\operatorname{Hom}\\left(F^{\\bullet}, K^{\\bullet}\\right) \\otimes_{\\mathfrak{o}} E $$ ^c425ae\n\nAdmissible triangles in $D_{c}^{b}(X, E)$ are triangles, which are isomorphic in $D_{c}^{b}(X, E)$ to admissible triangles in $D_{c}^{b}(X, \\mathfrak{o})$.\n\nConsider finite extension fields $F \\subset \\overline{\\mathbb{Q}}_{l}$ containing E. Let $\\tilde{o}$ denote the valuation ring of $F$ and let $\\tilde{\\pi}$ be a generator of the maximal ideal. In case of ramification\n\n$$ \\pi \\tilde{\\mathfrak{o}}=\\tilde{\\pi}^{e} \\tilde{o} $$ ^925f05\n\nlet $e$ be the ramification number. We construct natural functors\n\n$$ D_{c}^{b}(X, E) \\rightarrow D_{c}^{b}(X, F) $$ ^429009\n\nA. $\\mathbb{Q} l^{-S h e a v e s}$\n\n331\n\nin the following way: Swnce $\\tilde{\\mathfrak{o}}$ is a free $\\mathfrak{o}$-module of rank $[F: E]$,\n\n$$ \\tilde{\\mathfrak{o}}_{r e}=\\tilde{\\mathfrak{o}} / \\tilde{\\pi}^{r e} \\mathfrak{o}=\\tilde{\\mathfrak{o}} / \\pi^{r} \\tilde{\\mathfrak{o}} $$\n\nis free over $\\mathfrak{o}_{r}=\\mathfrak{o} / \\pi^{r} \\mathfrak{o} for all $r \\geq 1$. Consider first the functors\n\n$$ \\begin{gathered} D_{c t f}^{b}\\left(X, \\mathfrak{o}_{r}\\right) \\rightarrow D_{c t f}^{b}\\left(X, \\tilde{o}_{r e}\\right) \\\\ K^{\\bullet} \\mapsto K^{} \\otimes_{o_{r}} \\tilde{\\mathfrak{o}}_{r e}=K^{\\bullet} _{\\mathfrak{o}_{r}}^{L} \\tilde{\\mathfrak{o}}_{r e} \\end{gathered} $$$\n\n\n\nThe family of these functors for $r=1,2, \\ldots$ naturally defines a functor\n\n$$``\\varprojlim_r\'\' D_{ctf}^b(X, \\mathfrak{o}_r) \\to ``\\varprojlim_r\'\' D_{ctf}^b(X, \\tilde{\\mathfrak{o}}_{re}) = ``\\varprojlim_r\'\' D_{ctf}^b(X, \\tilde{\\mathfrak{o}}_{r\'}),$$\n\n\n\nhence by definition a functor\n\n$$ D_{c}^{b}(X, \\mathfrak{o}) \\rightarrow D_{c}^{b}(X, \\tilde{\\mathfrak{o}}) $$$ ^807c7e\n\nBy localization, as above, we get from this the desired functor\n\n$$ D_{c}^{b}(X, E) \\rightarrow D_{c}^{b}(X, F) $$\n\nFinally the category $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$ is defined as the direct limit\n\n$$ D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)= ``\\lim _{r} " D_{c t f}^{b}(X, E) $$ ^2e1ccf\n\n(in the obvious way) of the categories $D_{c}^{b}(X, E)$, where $E \\subset \\overline{\\mathbb{Q}}_{l}$ ranges over all finite extension fields of $\\mathbb{Q}_{l}$. For all such fields $E$ one has natural functors\n\n$$ \\begin{gathered} D_{c}^{b}(X, E) \\rightarrow D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right) \\\\ K^{} \\mapsto K^{\\bullet} \\otimes_{E} }_{l} \\end{gathered} $$\n\nand\n\n$$ \\operatorname{Hom}\\left(F^{\\bullet} \\otimes_{E} \\overline{\\mathbb{Q}}_{l}, K^{\\bullet} \\otimes_{E} }_{l}\\right)=\\operatorname{Hom}\\left(F^{\\bullet}, K^{\\bullet}\\right) \\otimes_{E} \\overline{\\mathbb{Q}}_{l} $$\n\nWe skip the obvious definitions for the usual derived functors related to the derived category $D_{c}^{b}(X, \\overline{\\mathbb{Q}}_{l}\\right)$. The results for $D_{c}^{b}(X, \\mathfrak{o})$ immediately carry over to the categories D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}). From the standard t-structure on $D_{c}^{b}(X, \\mathfrak{o})$, defined in Chap. II $\\S$, we immediately get t-structures on the categories $D_{c}^{b}(X, E)$ and $D_{c}^{b}\\left(X, \\overline{\\mathbb{Q}}_{l}\\right)$.\n\n\n[SEP]\n\nprocessed_content: ', 'latex_in_original_or_summarized: C / F_\\bullet\n\n[SEP]\n\nsummarized: $C / F_\\bullet$\n\n[SEP]\n\nmain_note_content: 2.4.5. This can be generalized as follows. For a simplicial object $F$. in $T$ we define a topos $T / F_{\\text {}}$ as follows. For each $[n] \\in $ we can consider the localized topos $T / F_{n}$. For a morphism $\\delta:[n] \\rightarrow[m]$ we have a morphism of topoi\n\n$$ \\delta: T / F_{m} \\rightarrow T / F_{n} $$\n\ndefined as in exercise 2.F. The category $T / F_{\\bullet}$ is defined to be the category of systems $\\left\\{\\left(G_{n}, _{n}, G()\\right)\\}_{n N}$ consisting of an object $\\epsilon_{n}: G_{n} \\rightarrow F_{n}$ in $T / F_{n}$ for each $n$, and for every morphism $\\delta:[n] [m]$ in $$ map\n\n$$ G(\\delta): G_{n} \\rightarrow \\delta_{*} G_{m} $$\n\nin $T / F_{n}$ such that for a composition\n\n$$ [n] \\stackrel{\\delta}{\\longrightarrow}[m] \\stackrel{\\epsilon}{}[k] $$\n\nthe map\n\n$$ G_{k} \\stackrel{G(\\epsilon)}{} _{*} G_{m} \\stackrel{\\epsilon_{*} G(\\delta)}{\\longrightarrow} \\epsilon_{*} \\delta_{*} G_{n} \\simeq(\\epsilon \\delta)_{*} G_{n} $$\n\nis equal to $G(\\epsilon \\delta)$. A morphism $\\left\\{\\left(G_{n}, \\epsilon_{n}, G(\\delta)\\right)\\right\\}_{n} \\rightarrow\\left\\{\\left(G_{n}^{\\prime}, \\epsilon_{n}, G^{\\prime}(\\delta)\\right)\\right\\}_{n}$ in $T / F_{\\bullet}$ is a collection of maps $\\left\\{h_{n}: G_{n} \\rightarrow G_{n}^{\\prime}\\right\\}_{n \\in \\mathbb{N}}$ in $T / F_{n}$ such that for any morphism $\\delta:[n] \\rightarrow[m]$ in $$ the diagram\n\ncommutes.\n\nWe can define a site $C / F_\\bullet$ such that $T / F_{\\bullet}$ is equivalent to the category of sheaves on $C / F_{\\bullet}$ as follows. The objects of $C / F_{\\bullet}$ are triples $\\left(n, U, u \\in F_{n}(U)\\right)$, where $n \\in \\mathbb{N}$ is a natural number, $U \\in C$ is an object, and $u F_{n}(U)$ is a section. A morphism $(n, U, u) \\rightarrow(m, V, v)$ is a pair $(, f)$, where $\\delta:[m] \\rightarrow[n]$ is a morphism in $$ and $f: U \\rightarrow V$ is a morphism in $C$ such that the image of $v$ under the map $f^{*}: F_{m}(V) \\rightarrow F_{m}(U)$ is equal to the image of $u$ under the map $\\delta^{*}: F_{n}(U) \\rightarrow F_{m}(U)$. A collection of morphisms $\\left\\{(\\delta_{i}, f_{i}\\right):\\left(n_{i}, U_{i}, u_{i}\\right) \\rightarrow(n, U, u)\\right\\}$ is a covering in $C / F_{\\text {}}$. if $n_{i}=n$ for all $i$, each $\\delta_{i}$ is the identity map, and the\n\n2.4. SIMPIICIAL TOPOI\n\n57\n\ncollection $\\left\\{f_{i}: U_{i} \\rightarrow U\\}$ is a covering in $C$. We leave it as exercise 2 .I that $C / F_{\\bullet}$ is a site with associated topos $T / F_{\\bullet}$.\n\n\n[SEP]\n\nprocessed_content: ', ] embeddings = model.encode(sentences) print(embeddings.shape) # [3, 384] # Get the similarity scores for the embeddings similarities = model.similarity(embeddings, embeddings) print(similarities.shape) # [3, 3] ``` ## Evaluation ### Metrics #### Binary Classification * Dataset: `relevance-val` * Evaluated with [BinaryClassificationEvaluator](https://sbert.net/docs/package_reference/sentence_transformer/evaluation.html#sentence_transformers.evaluation.BinaryClassificationEvaluator) | Metric | Value | |:--------------------------|:-----------| | cosine_accuracy | 0.8457 | | cosine_accuracy_threshold | 0.5248 | | cosine_f1 | 0.669 | | cosine_f1_threshold | 0.3437 | | cosine_precision | 0.6567 | | cosine_recall | 0.6819 | | **cosine_ap** | **0.6486** | | cosine_mcc | 0.5579 | ## Training Details ### Training Dataset #### Unnamed Dataset * Size: 264,888 training samples * Columns: sentence_0, sentence_1, and label * Approximate statistics based on the first 1000 samples: | | sentence_0 | sentence_1 | label | |:--------|:-------------------------------------------------------------------------------------|:-------------------------------------------------------------------------------------|:---------------------------------------------------------------| | type | string | string | float | | details | | | | * Samples: | sentence_0 | sentence_1 | label | |:---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:-----------------| | latex_in_original_or_summarized: {}^{\mathrm{P}} \mathrm{D}^{ 0}(\mathrm{X}, O)

[SEP]

summarized: ${}^{\mathrm{P}} D^{\leq 0}(\mathrm{X}, O)$

[SEP]

main_note_content: Def1inition 2.1.2. The subcategory ${}^{\mathrm{P}} D^{\leq 0}(\mathrm{X}, O)$ (resp. ${}^{} \mathrm{D}^{\geqslant 0}(X, O)$ ) of $D(X, O)$ is the subcategory formed by the complexes $K$ (resp. $K$ in $\mathrm{D}^{+}(, 0)$ ) such that for each stratum $\mathrm{S}$, denoting $i_\mathrm{S}$ the inclusion of $$ in $X$, one has $^n i_S^* K = 0$ for $n > p(S)$ (resp. $H^n i_S^! K = 0$ for $n < p(\mathrm{S})$).

The exactness of the functors ${}^O i^*$ allows us to reformulate the definition of ${}^P D^{\leqslant 0}(X, O)$: for $K$ to be in ${}^P D^{\leqslant 0}(X, O)$, it is necessaryeand sufficient that the restriction of $H^i K$ to $S$ is zero for $i>p(S)$. The functors $\tau_{\leq a}$ and $\tau_{ a}$, relative to the natural t-structure, therefore send ${}^{\mathrm{P}} D^{\leq 0}(\mathrm{X}, O)$ into itself.

If the fun...
| latex_in_original_or_summarized: f_*, f^*, f_{!}, f^{!}

[SEP]

summarized: $f^*$

[SEP]

main_note_content: o.0. Notations and terminology.

The reader will find at the end of this work a terminology index and an index of notations, containing the main new or non-standard terms or notations used.

Be careful that from 1.4 onwards, we generally simply denote by $f_*, f^*, f_{!}, f^{!}$ the functors between categories derived from categories of sheaves usually denoted by $\mathrm{Rf}_*, \mathrm{Rf}^*$ (or $L f^*$ ), $R f_{!}$ and $R f^{!}$, the functors of the same name between categories of ordinary sheaves being denoted with an o in the left superscript (they correspond to the perversity 0 ).

17

A.-A. BEILINSON, J. BERNSTEIN, P. DELIGNE


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processed_content:
| 1.0 | | latex_in_original_or_summarized: \theta: A_{\mathrm{inf}}\to \mathcal{O}

[SEP]

summarized: $\theta$

[SEP]

main_note_content: The proof of this (and the implicit functor) relies on a variant of Breuil--Kisin modules, due to Fargues, \cite{FarguesBK}, formulated in terms of Fontaine's period ring $A_{\mathrm{inf}}$ instead of the ring $\mathfrak{S}$. To explain this further, we recall the definitions The ring $A_{\mathrm{inf}}$ is defined as

$$ A_{\mathrm{inf}} = , $$ ^71cf0e

where $\mathcal{O}^\flat = \varprojlim_\varphi \mathcal{O}/p$ is the "tilt" of $\mathcal{O}$. Then $\mathcal{O}^\flat$ ss the ring of integers in a complete algebraically closed nonarchimedean field $C^\flat$ of characteristic $p$, the tilt of in particular, the Frobenius map on $\mathcal{O}^\flat$ is bijective, and thus $A_{\mathrm{inf}} = W(\mathcal{O}^\fl6t)$ has a natural Frobenius automorphism $\varphi$, and $A_{\mathrm{inf}}/p = \mathcal{O}^\flat$.

will need certain special elementis of $A_{\mathrm...
| latex_in_original_or_summarized:

[SEP]

summarized: $B_{\mathrm{dR}}^+$

[SEP]

main_note_content: proof of this result the implicit functor) relies on a variant of Breuil--Kisin modules, due to Fargues, \cite{FarguesBK}, formulated in terms Fontaine's period ring $A_{\mathrm{inf}}$ of the ring $\mathfrak{S}$. explain further, we recall the definitions first. The ring $A_{inf}$ is defined as

$$ = W(\mathcal{O}^\flat)\ , $$ ^71cf0e

where $\mathcal{O}^\flat$ = \varprojlim_\varphi \mathcal{O}/p$ is the "tilt" $\mathcal{O}$. Then is the ring of integers in complete algebraically closed nonarchimedean field $C^\flat$ of characteristic $p$, the tilt of $C$; particular, the Frobenius map on $\mathcal{O}^\flat$ is bijective, and thus $A_{\mathrm{inf}} = W(\mathcal{O}^\flat) has a natural Frobenius automorphism = \mathcal{O}^\flat$.

We will certain special elements $A_{\mathrm{inf}}$. Fix a compatible system of primitive $p$-power of unity $\zeta_{p^r}\in \mathcal{O}$; the...
| 0.0 | | latex_in_original_or_summarized: K(M, n)

[SEP]

summarized: $K(M, n)$

[SEP]

main_note_content: Chain complexes and spaces. [59], that for simplicial sheaf $\text{X}$ we denote by $C_{*}(\mathcal{X})$ the (normalized) chain complex $C_{*}(\mathcal{A}$ associated to the sheaf abelian groups $\mathbb{X}$. This defines a functor

$$ C_{*}: \Delta^{o p} S h v_{N i s}\left(S m_{k}\right) C_{*}(\text{A} b(k)) $$$ ^f7eebc

which is well (see $[44,59]$ instance) to have a right adjoint

6.2 \mathbb{A}^{1}$-Derived Category Spaces
161

$$ K: C_{*}(\mathcal{A} b(k)) \rightarrow \phi^{o p} S h v_{N i s}\left(S $$


called the space

For an abelian $M b(k)$ and an integer $n$ we define the pointed simplicial sheaf $K(M, n)$ (see [59, page 56]) $K$ to the shifted complex $M[n]$, the complex $M$ placed in degree 0 . If n< 0, the space $K(M, n)$ is a point. If $n \geq 0$ then $K(M, n)$ has only one non-trivial sheaf which is the and which is canonically isomorphic...
| latex_in_original_or_summarized: \langle u\rangle G W(F)

[SEP]

summarized: $\langle u\rangle \in G W(F)$

[SEP]

main_note_content: Let us denote (in characteristic) by $G W(F)$ the Grothendieck-Witt ring of isomorphism classes of non-degenerate symmetric bilinear forms [48]: this is the group completion of the commutative monoid of isomorphism classes of non-degenerate symmetric forms for the direct sum.

For $u \in F^{\times}$, we denote by $\langle u\rangle G W(F)$ the form on vector space of rank one given by $F^{2} F,(x, \mapsto u x y .$ By the results of loc. \langle u\rangle$ generate $G as a group. The following Lemma is (essentially) [48, Lemma (1.1) Chap. IV]:


[SEP]

processed_content:
| 0.0 | * Loss: [CosineSimilarityLoss](https://sbert.net/docs/package_reference/sentence_transformer/losses.html#cosinesimilarityloss) with these parameters: ```json { "loss_fct": "torch.nn.modules.loss.MSELoss" } ``` ### Training Hyperparameters #### Non-Default Hyperparameters - `eval_strategy`: steps - `per_device_train_batch_size`: 1 - `per_device_eval_batch_size`: 1 - `num_train_epochs`: 1 - `multi_dataset_batch_sampler`: round_robin #### All Hyperparameters
Click to expand - `overwrite_output_dir`: False - `do_predict`: False - `eval_strategy`: steps - `prediction_loss_only`: True - `per_device_train_batch_size`: 1 - `per_device_eval_batch_size`: 1 - `per_gpu_train_batch_size`: None - `per_gpu_eval_batch_size`: None - `gradient_accumulation_steps`: 1 - `eval_accumulation_steps`: None - `torch_empty_cache_steps`: None - `learning_rate`: 5e-05 - `weight_decay`: 0.0 - `adam_beta1`: 0.9 - `adam_beta2`: 0.999 - `adam_epsilon`: 1e-08 - `max_grad_norm`: 1 - `num_train_epochs`: 1 - `max_steps`: -1 - `lr_scheduler_type`: linear - `lr_scheduler_kwargs`: {} - `warmup_ratio`: 0.0 - `warmup_steps`: 0 - `log_level`: passive - `log_level_replica`: warning - `log_on_each_node`: True - `logging_nan_inf_filter`: True - `save_safetensors`: True - `save_on_each_node`: False - `save_only_model`: False - `restore_callback_states_from_checkpoint`: False - `no_cuda`: False - `use_cpu`: False - `use_mps_device`: False - `seed`: 42 - `data_seed`: None - `jit_mode_eval`: False - `use_ipex`: False - `bf16`: False - `fp16`: False - `fp16_opt_level`: O1 - `half_precision_backend`: auto - `bf16_full_eval`: False - `fp16_full_eval`: False - `tf32`: None - `local_rank`: 0 - `ddp_backend`: None - `tpu_num_cores`: None - `tpu_metrics_debug`: False - `debug`: [] - `dataloader_drop_last`: False - `dataloader_num_workers`: 0 - `dataloader_prefetch_factor`: None - `past_index`: -1 - `disable_tqdm`: False - `remove_unused_columns`: True - `label_names`: None - `load_best_model_at_end`: False - `ignore_data_skip`: False - `fsdp`: [] - `fsdp_min_num_params`: 0 - `fsdp_config`: {'min_num_params': 0, 'xla': False, 'xla_fsdp_v2': False, 'xla_fsdp_grad_ckpt': False} - `fsdp_transformer_layer_cls_to_wrap`: None - `accelerator_config`: {'split_batches': False, 'dispatch_batches': None, 'even_batches': True, 'use_seedable_sampler': True, 'non_blocking': False, 'gradient_accumulation_kwargs': None} - `deepspeed`: None - `label_smoothing_factor`: 0.0 - `optim`: adamw_torch - `optim_args`: None - `adafactor`: False - `group_by_length`: False - `length_column_name`: length - `ddp_find_unused_parameters`: None - `ddp_bucket_cap_mb`: None - `ddp_broadcast_buffers`: False - `dataloader_pin_memory`: True - `dataloader_persistent_workers`: False - `skip_memory_metrics`: True - `use_legacy_prediction_loop`: False - `push_to_hub`: False - `resume_from_checkpoint`: None - `hub_model_id`: None - `hub_strategy`: every_save - `hub_private_repo`: None - `hub_always_push`: False - `gradient_checkpointing`: False - `gradient_checkpointing_kwargs`: None - `include_inputs_for_metrics`: False - `include_for_metrics`: [] - `eval_do_concat_batches`: True - `fp16_backend`: auto - `push_to_hub_model_id`: None - `push_to_hub_organization`: None - `mp_parameters`: - `auto_find_batch_size`: False - `full_determinism`: False - `torchdynamo`: None - `ray_scope`: last - `ddp_timeout`: 1800 - `torch_compile`: False - `torch_compile_backend`: None - `torch_compile_mode`: None - `dispatch_batches`: None - `split_batches`: None - `include_tokens_per_second`: False - `include_num_input_tokens_seen`: False - `neftune_noise_alpha`: None - `optim_target_modules`: None - `batch_eval_metrics`: False - `eval_on_start`: False - `use_liger_kernel`: False - `eval_use_gather_object`: False - `average_tokens_across_devices`: False - `prompts`: None - `batch_sampler`: batch_sampler - `multi_dataset_batch_sampler`: round_robin
### Training Logs | Epoch | Step | Training Loss | relevance-val_cosine_ap | |:------:|:----:|:-------------:|:-----------------------:| | 0.0019 | 500 | 0.2362 | - | | 0.0038 | 1000 | 0.235 | - | | 0.0057 | 1500 | 0.2233 | - | | 0.0076 | 2000 | 0.2104 | - | | 0.0094 | 2500 | 0.1846 | - | | 0.0113 | 3000 | 0.1677 | - | | 0.0132 | 3500 | 0.1602 | - | | 0.0151 | 4000 | 0.1519 | 0.6486 | | 0.0170 | 4500 | 0.1323 | - | | 0.0189 | 5000 | 0.141 | - | | 0.0208 | 5500 | 0.1446 | - | | 0.0227 | 6000 | 0.1395 | - | | 0.0245 | 6500 | 0.1307 | - | | 0.0264 | 7000 | 0.1511 | - | | 0.0283 | 7500 | 0.1358 | - | | 0.0302 | 8000 | 0.1362 | 0.6486 | ### Framework Versions - Python: 3.12.9 - Sentence Transformers: 3.4.1 - Transformers: 4.48.3 - PyTorch: 2.5.1+cu124 - Accelerate: 1.3.0 - Datasets: 3.2.0 - Tokenizers: 0.21.0 ## Citation ### BibTeX #### Sentence Transformers ```bibtex @inproceedings{reimers-2019-sentence-bert, title = "Sentence-BERT: Sentence Embeddings using Siamese BERT-Networks", author = "Reimers, Nils and Gurevych, Iryna", booktitle = "Proceedings of the 2019 Conference on Empirical Methods in Natural Language Processing", month = "11", year = "2019", publisher = "Association for Computational Linguistics", url = "https://arxiv.org/abs/1908.10084", } ```