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\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*{Frames and Locales} \hypertarget{context}{}\subsubsection*{{Context}}\label{context} \hypertarget{category_theory}{}\paragraph*{{Category theory}}\label{category_theory} [[!include category theory - contents]] \hypertarget{topos_theory}{}\paragraph*{{Topos Theory}}\label{topos_theory} [[!include mathematicscontents]] This entry provides a hyperlinked index for the book \begin{itemize}% \item [[Jorge Picado]], [[Aleš Pultr]], \emph{Frames and Locales. Topology without points}, Frontiers in Mathematics, Birkhäuser (2012) \end{itemize} on basics of [[locales]] and [[pointfree topology]]. \hypertarget{contents}{}\section*{{Contents}}\label{contents} \noindent\hyperlink{i_spaces_and_lattices_of_open_sets}{I. Spaces and [[Lattices]] of Open Sets}\dotfill \pageref*{i_spaces_and_lattices_of_open_sets} \linebreak \noindent\hyperlink{ii_frames_and_locales_spectra}{II. [[Frames]] and [[Locales]]. Spectra}\dotfill \pageref*{ii_frames_and_locales_spectra} \linebreak \noindent\hyperlink{iii_sublocales}{III. [[Sublocales]]}\dotfill \pageref*{iii_sublocales} \linebreak \noindent\hyperlink{iv_structure_of_localic_morphisms_the_categories_loc_and_frm}{IV. Structure of [[Localic Morphisms]]. The Categories [[Loc]] and [[Frm]]}\dotfill \pageref*{iv_structure_of_localic_morphisms_the_categories_loc_and_frm} \linebreak \noindent\hyperlink{v_separation_axioms}{V. [[Separation Axioms]]}\dotfill \pageref*{v_separation_axioms} \linebreak \noindent\hyperlink{vi_more_on_sublocales}{VI. More on [[Sublocales]]}\dotfill \pageref*{vi_more_on_sublocales} \linebreak \noindent\hyperlink{vii_compactness_and_local_compactness}{VII. [[Compactness]] and [[Local Compactness]]}\dotfill \pageref*{vii_compactness_and_local_compactness} \linebreak \noindent\hyperlink{viii_symmetric_uniformity_and_nearness}{VIII. (Symmetric) Uniformity and Nearness}\dotfill \pageref*{viii_symmetric_uniformity_and_nearness} \linebreak \noindent\hyperlink{ix_paracompactness}{IX. [[Paracompactness]]}\dotfill \pageref*{ix_paracompactness} \linebreak \noindent\hyperlink{x_more_about_completion}{X. More about Completion}\dotfill \pageref*{x_more_about_completion} \linebreak \noindent\hyperlink{xi_metric_frames}{XI. [[Metric Frames]]}\dotfill \pageref*{xi_metric_frames} \linebreak \noindent\hyperlink{xii_entourages_asymmetric_uniformity}{XII. [[Entourages]]. [[Asymmetric Uniformity]]}\dotfill \pageref*{xii_entourages_asymmetric_uniformity} \linebreak \noindent\hyperlink{xiii_connectedness}{XIII. [[Connectedness]]}\dotfill \pageref*{xiii_connectedness} \linebreak \noindent\hyperlink{xiv_frame_of_reals_and_real_functions}{XIV. Frame of Reals and Real Functions}\dotfill \pageref*{xiv_frame_of_reals_and_real_functions} \linebreak \noindent\hyperlink{xv_localic_groups}{XV. [[Localic Groups]]}\dotfill \pageref*{xv_localic_groups} \linebreak \noindent\hyperlink{appendix_i_posets}{Appendix I. [[Posets]]}\dotfill \pageref*{appendix_i_posets} \linebreak \noindent\hyperlink{appendix_ii_categories}{Appendix II. Categories}\dotfill \pageref*{appendix_ii_categories} \linebreak The following lists chapterwise linked lists of keywords to relevant and related existing entries, as far as they already exist. \hypertarget{i_spaces_and_lattices_of_open_sets}{}\subsection*{{I. Spaces and [[Lattices]] of Open Sets}}\label{i_spaces_and_lattices_of_open_sets} \begin{enumerate}% \item [[Sober spaces]] \item The axiom $T_D$: another case of spaces easy to reconstruct \item Summing up \item Aside: several technical properties of $T_D$-spaces \end{enumerate} \hypertarget{ii_frames_and_locales_spectra}{}\subsection*{{II. [[Frames]] and [[Locales]]. Spectra}}\label{ii_frames_and_locales_spectra} \begin{enumerate}% \item [[Frames]] \item [[Locales]] and [[localic maps]] \item Points \item Spectra \item The unit σ and [[spatiality]] \item The unit λ and [[sobriety]] \end{enumerate} \hypertarget{iii_sublocales}{}\subsection*{{III. [[Sublocales]]}}\label{iii_sublocales} \begin{enumerate}% \item [[Extremal monomorphisms]] in [[Loc]] \item [[Sublocales]] \item The co-frame of [[sublocales]] \item Images and preimages \item Alternative representations of [[sublocales]] \item Open and [[closed sublocales]] \item Open and [[closed localic maps]] \item [[Closure]] \item Preimage as a homomorphism \item Other special sublocales: one-point sublocales, and [[Boolean locale|Boolean]] ones \item [[Sublocales]] as quotients. Factorizing frames is surprisingly easy \end{enumerate} \hypertarget{iv_structure_of_localic_morphisms_the_categories_loc_and_frm}{}\subsection*{{IV. Structure of [[Localic Morphisms]]. The Categories [[Loc]] and [[Frm]]}}\label{iv_structure_of_localic_morphisms_the_categories_loc_and_frm} \begin{enumerate}% \item Special morphisms. Factorizing in Loc and Frm \item The down-set functor and free constructions \item [[Limits]] and a [[colimit]] in [[Frm]] \item [[Coproducts]] of [[frames]] \item More on the structure of [[coproduct]] \item [[Epimorphisms]] in [[Frm]] \end{enumerate} \hypertarget{v_separation_axioms}{}\subsection*{{V. [[Separation Axioms]]}}\label{v_separation_axioms} \begin{enumerate}% \item Instead of $T_1$: [[subfit]] and [[fit]] \item Mimicking the [[Hausdorff axiom]] \item I-Hausdorff frames and [[regular monomorphisms]] \item Aside: Raney identity \item Quite like the classical case: [[Regular]], [[completely regular]] and [[normal]] \item The categories [[RegLoc]], [[CRegLoc]], [[HausLoc]] and [[FitLoc]] \end{enumerate} \hypertarget{vi_more_on_sublocales}{}\subsection*{{VI. More on [[Sublocales]]}}\label{vi_more_on_sublocales} \begin{enumerate}% \item Subspaces and [[sublocales]] of spaces \item Spatial and induced [[sublocales]] \item [[Complemented sublocales]] of spaces are spatial \item The [[zero-dimensionality]] of $Sl(L)^op$ and a few consequences \item Difference and pseudodifference, residua \item [[Isbell’s Development Theorem]] \item Locales with no non-spatial sublocales \item Spaces with no non-induced sublocales \end{enumerate} \hypertarget{vii_compactness_and_local_compactness}{}\subsection*{{VII. [[Compactness]] and [[Local Compactness]]}}\label{vii_compactness_and_local_compactness} \begin{enumerate}% \item Basics, and a technical lemma \item [[Compactness]] and [[separation]] \item Kuratowski-Mrówka characterization \item Compactification \item [[Well below]] and [[rather below]]. Continuous completely regular frames \item Continuous is the same as [[locally compact]]. [[Hofmann-Lawson duality]] \item One more spatiality theorem \item [[Supercompactness]]. Algebraic, superalgebraic and [[supercontinuous frames]] \end{enumerate} \hypertarget{viii_symmetric_uniformity_and_nearness}{}\subsection*{{VIII. (Symmetric) Uniformity and Nearness}}\label{viii_symmetric_uniformity_and_nearness} \begin{enumerate}% \item Background \item [[Uniformity]] and [[nearness]] in the point-free context \item Uniform homomorphisms. Modelling embeddings. Products \item Aside: admitting nearness in a weaker sense \item Compact uniform and nearness frames. Finite covers \item [[Completeness]] and [[completion]] \item Functoriality. [[CUniFrm]] is coreflective in [[UniFrm]] \item An easy completeness criterion \end{enumerate} \hypertarget{ix_paracompactness}{}\subsection*{{IX. [[Paracompactness]]}}\label{ix_paracompactness} \begin{enumerate}% \item [[Full normality]] \item [[Paracompactness]], and its various guises \item An elegant, specifically point-free, characterization of [[paracompactness]] \item A pleasant surprise: paracompact (co)reflection \end{enumerate} \hypertarget{x_more_about_completion}{}\subsection*{{X. More about Completion}}\label{x_more_about_completion} \begin{enumerate}% \item A variant of the [[completion of uniform frames]] \item Two applications \item Cauchy points and the resulting space \item [[Cauchy spectrum]] \item [[Cauchy completion]]. The case of countably generated uniformities \item Generalized Cauchy points \end{enumerate} \hypertarget{xi_metric_frames}{}\subsection*{{XI. [[Metric Frames]]}}\label{xi_metric_frames} \begin{enumerate}% \item Diameters and metric diameters \item Metric spectrum \item [[Uniform Metrization Theorem]] \item [[Metrization theorems]] for plain frames \item Categories of [[metric frames]] \end{enumerate} \hypertarget{xii_entourages_asymmetric_uniformity}{}\subsection*{{XII. [[Entourages]]. [[Asymmetric Uniformity]]}}\label{xii_entourages_asymmetric_uniformity} \begin{enumerate}% \item [[Entourages]] \item [[Uniformities]] via [[entourages]] \item [[Entourages]] versus [[covers]] \item [[Asymmetric uniformity]]: the classical case \item [[Biframes]] \item [[Quasi-uniformity]] in the point-free context via [[paircovers]] \item The adjunction $QUnif \leftrightarrows QUniFrm$ \item [[Quasi-uniformity]] in the point-free context via [[entourages]] \end{enumerate} \hypertarget{xiii_connectedness}{}\subsection*{{XIII. [[Connectedness]]}}\label{xiii_connectedness} \begin{enumerate}% \item A few observations about sublocales \item [[Connected]] and disconnected locales \item [[Locally connected]] locales \item A weird example \item A few notes \end{enumerate} \hypertarget{xiv_frame_of_reals_and_real_functions}{}\subsection*{{XIV. Frame of Reals and Real Functions}}\label{xiv_frame_of_reals_and_real_functions} \begin{enumerate}% \item The frame $L(R)$ of [[reals]] \item Properties of $L(R)$ \item $L(R)$ versus the usual space of reals \item The metric uniformity of $L(R)$ \item Continuous real functions \item [[Cozero]] elements \item More general real functions \item Notes \end{enumerate} \hypertarget{xv_localic_groups}{}\subsection*{{XV. [[Localic Groups]]}}\label{xv_localic_groups} \begin{enumerate}% \item Basics \item The category of [[localic groups]] \item [[Closed Subgroup Theorem]] \item The multiplication μ is open. The semigroup of open parts \item Uniformities \item Notes \end{enumerate} \hypertarget{appendix_i_posets}{}\subsection*{{Appendix I. [[Posets]]}}\label{appendix_i_posets} \begin{enumerate}% \item Basics \item [[Zorn’s Lemma]] \item [[Suprema]] and [[infima]] \item [[Semilattices]], [[lattices]] and [[complete lattices]]. Completion \item [[Galois connections]] (adjunctions) \item (Semi)lattices as algebras. [[Distributive lattices]] \item [[Pseudocomplements]] and [[complements]]. [[Heyting]] and [[Boolean algebras]] \end{enumerate} \hypertarget{appendix_ii_categories}{}\subsection*{{Appendix II. Categories}}\label{appendix_ii_categories} \begin{enumerate}% \item [[Categories]] \item [[Functors]] and [[natural transformations]] \item Some basic constructions \item More special morphisms. Factorization \item [[Limits]] and [[colimits]] \item [[Adjunction]] \item [[Adjointness]] and (co)limits \item Reflective and [[coreflective subcategories]] \item [[Monads]] \item Algebras in a category \end{enumerate} category: reference \end{document}