activity
20152026
most citedExodromy

5 citations · 12 across the 22 of their papers we have counts for

collaborators

25 papers

math.AG2026

The derived moduli of perverse sheaves

Peter J. Haine, Mauro Porta, Jean-Baptiste Teyssier

We construct higher derived Artin stacks parametrizing constructible sheaves on complex algebraic varieties and compact real analytic varieties. Furthermore, we show that every per…

math.CT2026

Classifying anima of condensed -categories of points

Peter J. Haine

We compare the classifying anima of two natural condensed -categories associated to a coherent -topos. One from our work with Barwick and Glasman on exit-path categ…

math.KT2025

Localizing invariants of constructible sheaves

Qingyuan Bai, Peter J. Haine

Given an open-closed decomposition of the stratifying poset, we construct a new semi-orthogonal decomposition of the -category of constructible sheaves on a stratified spac…

math.AG2025

The condensed homotopy type of a scheme

Peter J. Haine, Tim Holzschuh, Marcin Lara +3

We study a condensed version of the étale homotopy type of a scheme, which refines both the usual étale homotopy type of Friedlander-Artin-Mazur and the proétale fundamental group…

math.CT2025

Standard -structures

Peter J. Haine, Mauro Porta, Jean-Baptiste Teyssier

We provide a general construction of induced -structures, that generalizes standard -structures for -categories of sheaves. More precisely, given a presentable $\inft…

math.CT2025

Fully faithful functors and pushouts of -categories

Peter J. Haine, Maxime Ramzi, Jan Steinebrunner

We study stability properties of fully faithful functors, and compute mapping anima in pushouts of -categories along fully faithful functors. We provide applications of the…

math.AG2024

Reconstruction of schemes from their étale topoi

Magnus Carlson, Peter J. Haine, Sebastian Wolf

Let be a field that is finitely generated over its prime field. In Grothendieck's anabelian letter to Faltings, he conjectured that sending a -scheme to its étale topos defi…

math.AT2024

Profinite completions of products

Peter J. Haine

A source of difficulty in profinite homotopy theory is that the profinite completion functor does not preserve finite products. In this note, we provide a new, checkable criterion…

math.AT2024

Exodromy beyond conicality

Peter J. Haine, Mauro Porta, Jean-Baptiste Teyssier

We show that compact subanalytic stratified spaces and algebraic stratifications of real varieties have finite exit-path -categories, refining classical theorems of Lefsche…

math.AG2023

Spectral weight filtrations

Peter J. Haine, Piotr Pstrągowski

We provide a description of Voevodsky's -category of motivic spectra in terms of the subcategory of motives of smooth proper varieties. As applications, we construct weight…

math.AG2023

Nonabelian basechange theorems & étale homotopy theory

Peter J. Haine, Tim Holzschuh, Sebastian Wolf

This paper has two main goals. First, we prove nonabelian refinements of basechange theorems in étale cohomology (i.e., prove analogues of the classical statements for sheaves of s…

math.AT2022★ 1 cited

Descent for sheaves on compact Hausdorff spaces

Peter J. Haine

These notes explain some descent results for -categories of sheaves on compact Hausdorff spaces and derive some consequences. Specifically, given a compactly assembled $\in…

math.AT2022

The fundamental fiber sequence in étale homotopy theory

Peter J. Haine, Tim Holzschuh, Sebastian Wolf

Let be a field with separable closure , and let be a qcqs -scheme. We use the theory of profinite Galois categories developed by Barwick-Glasman-Haine…

math.AT2021★ 1 cited

Differential Cohomology: Categories, Characteristic Classes, and Connections

Araminta Amabel, Arun Debray, Peter J. Haine

We give an overview of differential cohomology from a modern, homotopy-theoretic perspective in terms of sheaves on manifolds. Although modern techniques are used, we base our disc…

math.CT2021★ 1 cited

From nonabelian basechange to basechange with coefficients

Peter J. Haine

The goal of this paper is to explain when basechange theorems for sheaves of spaces imply basechange for sheaves with coefficients in other presentable -categories. We acco…

math.AT2020

The homotopy-invariance of constructible sheaves

Peter J. Haine, Mauro Porta, Jean-Baptiste Teyssier

The purpose of this paper is to explain why the functor that sends a stratified topological space to the -category of constructible (hyper)sheaves on with coefficie…

math.AT2019

On the James and Hilton-Milnor Splittings, & the metastable EHP sequence

Sanath K. Devalapurkar, Peter J. Haine

This note provides modern proofs of some classical results in algebraic topology, such as the James Splitting, the Hilton-Milnor Splitting, and the metastable EHP sequence. We prov…

math.AG2019

Pyknotic objects, I. Basic notions

Clark Barwick, Peter Haine

Pyknotic objects are (hyper)sheaves on the site of compacta. These provide a convenient way to do algebra and homotopy theory with additional topological information present. This…

math.AG2019★ 2 cited

On coherent topoi & coherent -localic -topoi

Peter J. Haine

In this note we prove the following useful fact that seems to be missing from the literature: the -category of coherent ordinary topoi (in the sense of SGA4) is equivalent…

math.AG2019

Exodromy for stacks

Clark Barwick, Peter Haine

In this short note we extend the Exodromy Theorem of arXiv:1807.03281 to a large class of stacks and higher stacks. We accomplish this by extending the Galois category construction…

math.AG2019

Extended étale homotopy groups from profinite Galois categories

Peter J. Haine

In this note we show that the protruncated shape of a spectral -topos is a delocalization of its profinite stratified shape. This gives a way to reconstruct the extended ét…

math.AT2018★ 1 cited

On the homotopy theory of stratified spaces

Peter J. Haine

Let be a poset. We define a new homotopy theory of suitably nice -stratified topological spaces with equivalences on strata and links inverted. We show that the exit-path co…

math.AT2018★ 5 cited

Exodromy

Clark Barwick, Saul Glasman, Peter Haine

Let be a quasicompact quasiseparated scheme. Write for the category whose objects are geometric points of and whose morphisms are specializations in…

math.CT2016★ 1 cited

Lifting Enhanced Factorization Systems to Functor -Categories

Peter J. Haine

In this paper we give sufficient conditions for lifting an enhanced factorization system on a -category to the functor -cate…