Locally Non-Measurable Functions with Many Continuity Points

It is well known that every continuous function on the space of real numbers is Lebesgue measurable. Also, if a function is continuous almost everywhere, then it is automatically measurable. Thus, local non-measurability seems, at first glance, to exclude continuity. But is this really the case? In this note we will show that actually every $G_\delta$-set with empty interior and locally big complement (in the sense of measure theory) can be prescribed as the set of continuity points of locally non-measurable functions.

Authors

Institutions

Publication Details

Journal
Real Analysis Exchange
Published
2024-12-21
DOI
https://doi.org/10.14321/realanalexch.1721604244
Citations
1
Primary Topic
advanced mathematical theories
Type
article
Field-Weighted Citation Impact
0.89
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

Locally Non-Measurable Functions with Many Continuity Points

Raymond Mortini, Peter Pflug, Gerd Herzog
1 citations
Real Analysis Exchange
advanced mathematical theories
0.89
article

Locally Non-Measurable Functions with Many Continuity Points

Raymond Mortini, Peter Pflug, Gerd Herzog
article en
1 citations

Abstract

It is well known that every continuous function on the space of real numbers is Lebesgue measurable. Also, if a function is continuous almost everywhere, then it is automatically measurable. Thus, local non-measurability seems, at first glance, to exclude continuity. But is this really the case? In this note we will show that actually every $G_\delta$-set with empty interior and locally big complement (in the sense of measure theory) can be prescribed as the set of continuity points of locally non-measurable functions.

Real Analysis ExchangeVol. 50(1)
Karlsruhe Institute of Technology (DE), Centre National de la Recherche Scientifique (FR), Carl von Ossietzky Universität Oldenburg (DE), University of Luxembourg (LU), DVGW-Forschungsstelle am Engler-Bunte-Institut des Karlsruher Instituts für Technologie (DE)
Openalex Percentile: Top 25%
advanced mathematical theories
0.89
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.