\documentclass[12pt,titlepage]{article} \usepackage{amsmath} \usepackage{mathrsfs} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsthm} \usepackage{mathtools} \usepackage{graphicx} \usepackage{color} \usepackage{ucs} \usepackage[utf8x]{inputenc} \usepackage{xparse} \usepackage{hyperref} %----Macros---------- % % Unresolved issues: % % \righttoleftarrow % \lefttorightarrow % % \color{} with HTML colorspec % \bgcolor % \array with options (without options, it's equivalent to the matrix environment) % Of the standard HTML named colors, white, black, red, green, blue and yellow % are predefined in the color package. Here are the rest. \definecolor{aqua}{rgb}{0, 1.0, 1.0} \definecolor{fuschia}{rgb}{1.0, 0, 1.0} \definecolor{gray}{rgb}{0.502, 0.502, 0.502} \definecolor{lime}{rgb}{0, 1.0, 0} \definecolor{maroon}{rgb}{0.502, 0, 0} \definecolor{navy}{rgb}{0, 0, 0.502} \definecolor{olive}{rgb}{0.502, 0.502, 0} \definecolor{purple}{rgb}{0.502, 0, 0.502} \definecolor{silver}{rgb}{0.753, 0.753, 0.753} \definecolor{teal}{rgb}{0, 0.502, 0.502} % Because of conflicts, \space and \mathop are converted to % \itexspace and \operatorname during preprocessing. % itex: \space{ht}{dp}{wd} % % Height and baseline depth measurements are in units of tenths of an ex while % the width is measured in tenths of an em. \makeatletter \newdimen\itex@wd% \newdimen\itex@dp% \newdimen\itex@thd% \def\itexspace#1#2#3{\itex@wd=#3em% \itex@wd=0.1\itex@wd% \itex@dp=#2ex% \itex@dp=0.1\itex@dp% \itex@thd=#1ex% \itex@thd=0.1\itex@thd% \advance\itex@thd\the\itex@dp% \makebox[\the\itex@wd]{\rule[-\the\itex@dp]{0cm}{\the\itex@thd}}} \makeatother % \tensor and \multiscript \makeatletter \newif\if@sup \newtoks\@sups \def\append@sup#1{\edef\act{\noexpand\@sups={\the\@sups #1}}\act}% \def\reset@sup{\@supfalse\@sups={}}% \def\mk@scripts#1#2{\if #2/ \if@sup ^{\the\@sups}\fi \else% \ifx #1_ \if@sup ^{\the\@sups}\reset@sup \fi {}_{#2}% \else \append@sup#2 \@suptrue \fi% \expandafter\mk@scripts\fi} \def\tensor#1#2{\reset@sup#1\mk@scripts#2_/} \def\multiscripts#1#2#3{\reset@sup{}\mk@scripts#1_/#2% \reset@sup\mk@scripts#3_/} \makeatother % \slash \makeatletter \newbox\slashbox \setbox\slashbox=\hbox{$/$} \def\itex@pslash#1{\setbox\@tempboxa=\hbox{$#1$} \@tempdima=0.5\wd\slashbox \advance\@tempdima 0.5\wd\@tempboxa \copy\slashbox \kern-\@tempdima \box\@tempboxa} \def\slash{\protect\itex@pslash} \makeatother % math-mode versions of \rlap, etc % from Alexander Perlis, "A complement to \smash, \llap, and lap" % http://math.arizona.edu/~aprl/publications/mathclap/ \def\clap#1{\hbox to 0pt{\hss#1\hss}} \def\mathllap{\mathpalette\mathllapinternal} \def\mathrlap{\mathpalette\mathrlapinternal} \def\mathclap{\mathpalette\mathclapinternal} \def\mathllapinternal#1#2{\llap{$\mathsurround=0pt#1{#2}$}} \def\mathrlapinternal#1#2{\rlap{$\mathsurround=0pt#1{#2}$}} \def\mathclapinternal#1#2{\clap{$\mathsurround=0pt#1{#2}$}} % Renames \sqrt as \oldsqrt and redefine root to result in \sqrt[#1]{#2} \let\oldroot\root \def\root#1#2{\oldroot #1 \of{#2}} \renewcommand{\sqrt}[2][]{\oldroot #1 \of{#2}} % Manually declare the txfonts symbolsC font \DeclareSymbolFont{symbolsC}{U}{txsyc}{m}{n} \SetSymbolFont{symbolsC}{bold}{U}{txsyc}{bx}{n} \DeclareFontSubstitution{U}{txsyc}{m}{n} % Manually declare the stmaryrd font \DeclareSymbolFont{stmry}{U}{stmry}{m}{n} \SetSymbolFont{stmry}{bold}{U}{stmry}{b}{n} % Manually declare the MnSymbolE font \DeclareFontFamily{OMX}{MnSymbolE}{} \DeclareSymbolFont{mnomx}{OMX}{MnSymbolE}{m}{n} \SetSymbolFont{mnomx}{bold}{OMX}{MnSymbolE}{b}{n} \DeclareFontShape{OMX}{MnSymbolE}{m}{n}{ <-6> MnSymbolE5 <6-7> MnSymbolE6 <7-8> MnSymbolE7 <8-9> MnSymbolE8 <9-10> MnSymbolE9 <10-12> MnSymbolE10 <12-> MnSymbolE12}{} % Declare specific arrows from txfonts without loading the full package \makeatletter \def\re@DeclareMathSymbol#1#2#3#4{% \let#1=\undefined \DeclareMathSymbol{#1}{#2}{#3}{#4}} \re@DeclareMathSymbol{\neArrow}{\mathrel}{symbolsC}{116} \re@DeclareMathSymbol{\neArr}{\mathrel}{symbolsC}{116} \re@DeclareMathSymbol{\seArrow}{\mathrel}{symbolsC}{117} \re@DeclareMathSymbol{\seArr}{\mathrel}{symbolsC}{117} \re@DeclareMathSymbol{\nwArrow}{\mathrel}{symbolsC}{118} \re@DeclareMathSymbol{\nwArr}{\mathrel}{symbolsC}{118} \re@DeclareMathSymbol{\swArrow}{\mathrel}{symbolsC}{119} \re@DeclareMathSymbol{\swArr}{\mathrel}{symbolsC}{119} \re@DeclareMathSymbol{\nequiv}{\mathrel}{symbolsC}{46} \re@DeclareMathSymbol{\Perp}{\mathrel}{symbolsC}{121} \re@DeclareMathSymbol{\Vbar}{\mathrel}{symbolsC}{121} \re@DeclareMathSymbol{\sslash}{\mathrel}{stmry}{12} \re@DeclareMathSymbol{\bigsqcap}{\mathop}{stmry}{"64} \re@DeclareMathSymbol{\biginterleave}{\mathop}{stmry}{"6} \re@DeclareMathSymbol{\invamp}{\mathrel}{symbolsC}{77} \re@DeclareMathSymbol{\parr}{\mathrel}{symbolsC}{77} \makeatother % \llangle, \rrangle, \lmoustache and \rmoustache from MnSymbolE \makeatletter \def\Decl@Mn@Delim#1#2#3#4{% \if\relax\noexpand#1% \let#1\undefined \fi \DeclareMathDelimiter{#1}{#2}{#3}{#4}{#3}{#4}} \def\Decl@Mn@Open#1#2#3{\Decl@Mn@Delim{#1}{\mathopen}{#2}{#3}} \def\Decl@Mn@Close#1#2#3{\Decl@Mn@Delim{#1}{\mathclose}{#2}{#3}} \Decl@Mn@Open{\llangle}{mnomx}{'164} \Decl@Mn@Close{\rrangle}{mnomx}{'171} \Decl@Mn@Open{\lmoustache}{mnomx}{'245} \Decl@Mn@Close{\rmoustache}{mnomx}{'244} \makeatother % Widecheck \makeatletter \DeclareRobustCommand\widecheck[1]{{\mathpalette\@widecheck{#1}}} \def\@widecheck#1#2{% \setbox\z@\hbox{\m@th$#1#2$}% \setbox\tw@\hbox{\m@th$#1% \widehat{% \vrule\@width\z@\@height\ht\z@ \vrule\@height\z@\@width\wd\z@}$}% \dp\tw@-\ht\z@ \@tempdima\ht\z@ \advance\@tempdima2\ht\tw@ \divide\@tempdima\thr@@ \setbox\tw@\hbox{% \raise\@tempdima\hbox{\scalebox{1}[-1]{\lower\@tempdima\box \tw@}}}% {\ooalign{\box\tw@ \cr \box\z@}}} \makeatother % \mathraisebox{voffset}[height][depth]{something} \makeatletter \NewDocumentCommand\mathraisebox{moom}{% \IfNoValueTF{#2}{\def\@temp##1##2{\raisebox{#1}{$\m@th##1##2$}}}{% \IfNoValueTF{#3}{\def\@temp##1##2{\raisebox{#1}[#2]{$\m@th##1##2$}}% }{\def\@temp##1##2{\raisebox{#1}[#2][#3]{$\m@th##1##2$}}}}% \mathpalette\@temp{#4}} \makeatletter % udots (taken from yhmath) \makeatletter \def\udots{\mathinner{\mkern2mu\raise\p@\hbox{.} \mkern2mu\raise4\p@\hbox{.}\mkern1mu \raise7\p@\vbox{\kern7\p@\hbox{.}}\mkern1mu}} \makeatother %% Fix array \newcommand{\itexarray}[1]{\begin{matrix}#1\end{matrix}} %% \itexnum is a noop \newcommand{\itexnum}[1]{#1} %% Renaming existing commands \newcommand{\underoverset}[3]{\underset{#1}{\overset{#2}{#3}}} \newcommand{\widevec}{\overrightarrow} \newcommand{\darr}{\downarrow} \newcommand{\nearr}{\nearrow} \newcommand{\nwarr}{\nwarrow} \newcommand{\searr}{\searrow} \newcommand{\swarr}{\swarrow} \newcommand{\curvearrowbotright}{\curvearrowright} \newcommand{\uparr}{\uparrow} \newcommand{\downuparrow}{\updownarrow} \newcommand{\duparr}{\updownarrow} \newcommand{\updarr}{\updownarrow} \newcommand{\gt}{>} \newcommand{\lt}{<} \newcommand{\map}{\mapsto} \newcommand{\embedsin}{\hookrightarrow} \newcommand{\Alpha}{A} \newcommand{\Beta}{B} \newcommand{\Zeta}{Z} \newcommand{\Eta}{H} \newcommand{\Iota}{I} \newcommand{\Kappa}{K} \newcommand{\Mu}{M} \newcommand{\Nu}{N} \newcommand{\Rho}{P} \newcommand{\Tau}{T} \newcommand{\Upsi}{\Upsilon} \newcommand{\omicron}{o} \newcommand{\lang}{\langle} \newcommand{\rang}{\rangle} \newcommand{\Union}{\bigcup} \newcommand{\Intersection}{\bigcap} \newcommand{\Oplus}{\bigoplus} \newcommand{\Otimes}{\bigotimes} \newcommand{\Wedge}{\bigwedge} \newcommand{\Vee}{\bigvee} \newcommand{\coproduct}{\coprod} \newcommand{\product}{\prod} \newcommand{\closure}{\overline} \newcommand{\integral}{\int} \newcommand{\doubleintegral}{\iint} \newcommand{\tripleintegral}{\iiint} \newcommand{\quadrupleintegral}{\iiiint} \newcommand{\conint}{\oint} \newcommand{\contourintegral}{\oint} \newcommand{\infinity}{\infty} \newcommand{\bottom}{\bot} \newcommand{\minusb}{\boxminus} \newcommand{\plusb}{\boxplus} \newcommand{\timesb}{\boxtimes} \newcommand{\intersection}{\cap} \newcommand{\union}{\cup} \newcommand{\Del}{\nabla} \newcommand{\odash}{\circleddash} \newcommand{\negspace}{\!} \newcommand{\widebar}{\overline} \newcommand{\textsize}{\normalsize} \renewcommand{\scriptsize}{\scriptstyle} \newcommand{\scriptscriptsize}{\scriptscriptstyle} \newcommand{\mathfr}{\mathfrak} \newcommand{\statusline}[2]{#2} \newcommand{\tooltip}[2]{#2} \newcommand{\toggle}[2]{#2} % Theorem Environments \theoremstyle{plain} \newtheorem{theorem}{Theorem} \newtheorem{lemma}{Lemma} \newtheorem{prop}{Proposition} \newtheorem{cor}{Corollary} \newtheorem*{utheorem}{Theorem} \newtheorem*{ulemma}{Lemma} \newtheorem*{uprop}{Proposition} \newtheorem*{ucor}{Corollary} \theoremstyle{definition} \newtheorem{defn}{Definition} \newtheorem{example}{Example} \newtheorem*{udefn}{Definition} \newtheorem*{uexample}{Example} \theoremstyle{remark} \newtheorem{remark}{Remark} \newtheorem{note}{Note} \newtheorem*{uremark}{Remark} \newtheorem*{unote}{Note} %------------------------------------------------------------------- \begin{document} %------------------------------------------------------------------- \section*{differential algebraic K-theory} \begin{quote}% under construction \end{quote} \hypertarget{context}{}\subsubsection*{{Context}}\label{context} \hypertarget{differential_cohomology}{}\paragraph*{{Differential cohomology}}\label{differential_cohomology} [[!include differential cohomology - contents]] \hypertarget{arithmetic_geometry}{}\paragraph*{{Arithmetic geometry}}\label{arithmetic_geometry} [[!include arithmetic geometry - contents]] \hypertarget{cohesive_toposes}{}\paragraph*{{Cohesive $\infty$-Toposes}}\label{cohesive_toposes} [[!include cohesive infinity-toposes - contents]] \hypertarget{contents}{}\section*{{Contents}}\label{contents} \noindent\hyperlink{idea}{Idea}\dotfill \pageref*{idea} \linebreak \noindent\hyperlink{definition}{Definition}\dotfill \pageref*{definition} \linebreak \noindent\hyperlink{absolute_hodge_cohomology}{Absolute Hodge cohomology}\dotfill \pageref*{absolute_hodge_cohomology} \linebreak \noindent\hyperlink{AlgebraicKTheorySheafOfSpectra}{Algebraic K-theory sheaf of spectra}\dotfill \pageref*{AlgebraicKTheorySheafOfSpectra} \linebreak \noindent\hyperlink{RefinedBeilinsoRegulator}{The refined Beilinson regulator}\dotfill \pageref*{RefinedBeilinsoRegulator} \linebreak \noindent\hyperlink{differential_algebraic_ktheory}{Differential algebraic K-theory}\dotfill \pageref*{differential_algebraic_ktheory} \linebreak \noindent\hyperlink{applications}{Applications}\dotfill \pageref*{applications} \linebreak \noindent\hyperlink{related_concepts}{Related concepts}\dotfill \pageref*{related_concepts} \linebreak \noindent\hyperlink{references}{References}\dotfill \pageref*{references} \linebreak \hypertarget{idea}{}\subsection*{{Idea}}\label{idea} Differential algebraic K-theory is the [[differential cohomology]]-refinement of [[algebraic K-theory]]. In (\hyperlink{BunkeTamme12}{Bunke-Tamme 12}) this is realized effectively as the [[schreiber:differential cohomology in a cohesive topos]] of the [[tangent (∞,1)-topos]] of the [[cohesive (∞,1)-topos]] \begin{displaymath} \mathbf{H} \coloneqq Sh_\infty\left(SmthMfd, \mathbf{B} \right) \stackrel{\overset{\Pi}{\longrightarrow}}{\stackrel{\overset{Disc}{\leftarrow}}{\stackrel{\overset{\Gamma}{\longrightarrow}}{\underset{coDisc}{\leftarrow}}}} \mathbf{B} \end{displaymath} of [[∞-stacks]] on the [[site]] of [[smooth manifolds]] with values in turn in [[∞-stacks]] over a [[site]] of [[arithmetic schemes]], hence by [[smooth ∞-groupoids]] but over a [[base (∞,1)-topos]] \begin{displaymath} \mathbf{B} \coloneqq Sh_\infty\left(Sch_{\mathbb{Z}}\right) \end{displaymath} of algebraic [[∞-stacks]]. This may be regarded as sitting inside the [[smooth E-∞-groupoids]]. It is observed in this context that the [[Beilinson regulator]] in [[algebraic K-theory]] is naturally understood as a [[Chern character]] in this perspective of [[differential cohomology]] (\hyperlink{BunkeTamme12}{Bunke-Tamme 12}), which helps with studying it. \hypertarget{definition}{}\subsection*{{Definition}}\label{definition} \hypertarget{absolute_hodge_cohomology}{}\subsubsection*{{Absolute Hodge cohomology}}\label{absolute_hodge_cohomology} \begin{defn} \label{HodgeComplexOverComplexNumbers}\hypertarget{HodgeComplexOverComplexNumbers}{} Write \begin{displaymath} \Omega^\bullet_{\mathbb{C}} \in Stab(Sh_\infty(Sch_{\mathbb{C}})) \end{displaymath} for the [[chain complex]] of [[abelian sheaves]] (regarded as a [[sheaf of spectra]] under the [[stable Dold-Kan correspondence]]) which computes [[absolute Hodge cohomology]] of [[complex varieties]]. \end{defn} (\hyperlink{BunkeTamme12}{Bunke-Tamme 12, section 3.1}) \begin{defn} \label{HodgeComplexOverIntegers}\hypertarget{HodgeComplexOverIntegers}{} Write \begin{displaymath} \Omega^\bullet_{\mathbb{Z}} \coloneqq compl^\ast \Omega^\bullet_{\mathbb{C}} \in Stab(\mathbf{B}) \end{displaymath} for the [[inverse image]] of $\Omega^\bullet_{\mathbb{C}}$ under the [[base change]] given by \begin{displaymath} compl \coloneqq (-)\times_{\mathbb{Z}}Spec(\mathbb{C}) \;\colon\; Sch_{\mathbb{Z}}\longrightarrow Sch_{\mathbb{C}} \,. \end{displaymath} \end{defn} (\hyperlink{BunkeTamme12}{Bunke-Tamme 12, section 3.2}) There is a resolution of $\Omega^\bullet_{\mathbb{Z}} \in Stab(\mathbf{B}) \stackrel{Disc}{\hookrightarrow} Stab(\mathbf{H})$ by a sheaf of complexes of differential forms on smooth manifolds tensored with $\Omega^\bullet_{\mathbb{Z}}$ \begin{displaymath} \Omega^\bullet \in Stab(\mathbf{H}) \end{displaymath} (\hyperlink{BunkeTamme12}{Bunke-Tamme 12, (47)}). \begin{defn} \label{CyclesForHodgeComplexOverComplexNumbers}\hypertarget{CyclesForHodgeComplexOverComplexNumbers}{} While $\Omega^\bullet \simeq \Omega^\bullet_{\mathbb{Z}}$, below we use the chain-level truncation $\Omega^{\bullet \geq 0}$ which is no longer in the image of $Disc$, hence no longer a [[flat modality]]-[[modal type]]. \end{defn} \hypertarget{AlgebraicKTheorySheafOfSpectra}{}\subsubsection*{{Algebraic K-theory sheaf of spectra}}\label{AlgebraicKTheorySheafOfSpectra} Write \begin{displaymath} \mathbf{Vect}_{lc} \in \mathbf{H} \end{displaymath} for the [[stack]] which to $X\times S \in SmthMfd \times Sch_{\mathbb{Z}}$ assigns the groupoid of locally free and locally finitely generated $pr_S^\ast \mathcal{O}_S$-[[modules]] (modules over the [[inverse image]] of the [[structure sheaf]] of $S$ under the [[projection]] map $X \times S \to S$). This is a [[commutative monoid]] object with respect to [[direct sum]]. Write \begin{displaymath} K \coloneqq \mathcal{K}(\mathbf{Vect}_{lc}^{\oplus}) \end{displaymath} for the stackification of the objectwise [[K-theory of a symmetric monoidal (∞,1)-category]]-construction. This is the ordinary [[algebraic K-theory]] of [[schemes]], as in (\hyperlink{ThomasonTrobaugh90}{Thomason-Trobaugh 90}) (\hyperlink{BunkeTamme12}{Bunke-Tamme 12, section 3.3}), see at \emph{\href{algebraic%20K-theory#AsTheKTheoryOfAlgebraicVectorBundles}{algebraic K-theory -- as the K-theory of algebraic vector bundles}}. \hypertarget{RefinedBeilinsoRegulator}{}\subsubsection*{{The refined Beilinson regulator}}\label{RefinedBeilinsoRegulator} There is a refinement of the [[Beilinson regulator]] to a smoothly parameterized version $\mathbf{K}$ of [[algebraic K-theory]]: \begin{defn} \label{TheBeilinsonRegulator}\hypertarget{TheBeilinsonRegulator}{} (\ldots{}) \begin{displaymath} r^{Beil} \;\colon\; K \longrightarrow \Omega^\bullet_{\mathbb{Z}} \end{displaymath} \end{defn} As a homomorphism of [[spectrum objects]] this is (\hyperlink{BunkeTamme12}{Bunke-Tamme 12, def. 4.26}). As a homomorphism of [[E-∞ ring]] objects, this is (\hyperlink{BunkeTamme13}{Bunke-Tamme 13, def. 2.18}). \hypertarget{differential_algebraic_ktheory}{}\subsubsection*{{Differential algebraic K-theory}}\label{differential_algebraic_ktheory} Recall the discussion at \emph{[[differential cohomology hexagon]]}. \begin{defn} \label{HodgeComplexOverComplexNumbers}\hypertarget{HodgeComplexOverComplexNumbers}{} \emph{Differential algebraic K-theory} is the [[homotopy fiber product]] \begin{displaymath} \hat K \coloneqq K \underset{\Omega^\bullet}{\times} \Omega^{\bullet \geq 0} \in Stab(\mathbf{H}) \end{displaymath} of the inclusion of the non-negative degree truncation of the de Rham resolution of the absolute Hodge complex, def. \ref{CyclesForHodgeComplexOverComplexNumbers}, with the refined Beilinson regulator, def. \ref{TheBeilinsonRegulator} \begin{displaymath} \itexarray{ \hat K &\longrightarrow& \Omega^{\bullet \geq 0} \\ \downarrow &(pb)& \downarrow \\ K &\underset{r^{Beil}}{\longrightarrow}& \Omega^\bullet } \,. \end{displaymath} \end{defn} (\hyperlink{BunkeTamme12}{Bunke-Tamme 12, def. 5.1}, \hyperlink{BunkeTamme13}{Bunke-Tamme 13, def. 3.1}). \hypertarget{applications}{}\subsection*{{Applications}}\label{applications} \begin{itemize}% \item differential refinement of [[Becker-Gottlieb transfer]] and its image under [[Borel regulators]]. See at \emph{[[transfer index conjecture]]}. \end{itemize} \hypertarget{related_concepts}{}\subsection*{{Related concepts}}\label{related_concepts} \begin{itemize}% \item [[differential K-theory]] \item [[differential form with logarithmic singularities]] \end{itemize} \hypertarget{references}{}\subsection*{{References}}\label{references} Differential algebraic K-theory as above is introduced and studied in \begin{itemize}% \item [[Ulrich Bunke]], [[Georg Tamme]], \emph{Regulators and cycle maps in higher-dimensional differential algebraic K-theory} (\href{http://arxiv.org/abs/1209.6451}{arXiv:1209.6451}) \item [[Ulrich Bunke]], [[David Gepner]], \emph{Differential function spectra, the differential Becker-Gottlieb transfer, and applications to differential algebraic K-theory} (\href{http://arxiv.org/abs/1306.0247}{arXiv:1306.0247}) \item [[Ulrich Bunke]], [[Georg Tamme]], \emph{Multiplicative differential algebraic K-theory and applications} (\href{http://arxiv.org/abs/1311.1421}{arXiv:1311.1421}) \end{itemize} Relevant references in ordinary [[algebraic K-theory]] include \begin{itemize}% \item [[Robert Thomason]] and Thomas Trobaugh, \emph{Higher algebraic K-theory of schemes and of derived categories}, The Grothendieck Festschrift, Vol. III, Progr. Math., vol. 88, Birkhauser Boston, Boston, MA, 1990, pp. 247-435. MR 1106918 (92f:19001) \end{itemize} [[!redirects differential algebraic K-theory]] [[!redirects differential algebraic K-theories]] [[!redirects differential algebraic K-theories]] \end{document}