EPPA FOR TWO-GRAPHS AND ANTIPODAL METRIC SPACES

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10414425" target="_blank" >RIV/00216208:11320/20:10414425 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=LEw1pquAfS" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=LEw1pquAfS</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1090/proc/14872" target="_blank" >10.1090/proc/14872</a>

Jazyk výsledku

angličtina

Název v původním jazyce

EPPA FOR TWO-GRAPHS AND ANTIPODAL METRIC SPACES

Popis výsledku v původním jazyce

We prove that the class of finite two-graphs has the extension property for partial automorphisms (EPPA, or Hrushovski property), thereby answering a question of Macpherson. In other words, we show that the class of graphs has the extension property for switching automorphisms. We present a short, self-contained, purely combinatorial proof which also proves EPPA for the class of integer-valued antipodal metric spaces of diameter 3, answering a question of Aranda et al. The class of two-graphs is an important new example which behaves differently from all the other known classes with EPPA: Two-graphs do not have the amalgamation property with automorphisms (APA), their Ramsey expansion has to add a graph, it is not known if they have coherent EPPA, and even EPPA itself cannot be proved using the Herwig-Lascar theorem.

Název v anglickém jazyce

EPPA FOR TWO-GRAPHS AND ANTIPODAL METRIC SPACES

Popis výsledku anglicky

We prove that the class of finite two-graphs has the extension property for partial automorphisms (EPPA, or Hrushovski property), thereby answering a question of Macpherson. In other words, we show that the class of graphs has the extension property for switching automorphisms. We present a short, self-contained, purely combinatorial proof which also proves EPPA for the class of integer-valued antipodal metric spaces of diameter 3, answering a question of Aranda et al. The class of two-graphs is an important new example which behaves differently from all the other known classes with EPPA: Two-graphs do not have the amalgamation property with automorphisms (APA), their Ramsey expansion has to add a graph, it is not known if they have coherent EPPA, and even EPPA itself cannot be proved using the Herwig-Lascar theorem.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10101 - Pure mathematics

Projekt

<a href="/cs/project/GJ18-13685Y" target="_blank" >GJ18-13685Y: Teorie modelů a extrémální kombinatorika</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Proceedings of the American Mathematical Society

ISSN

0002-9939

e-ISSN

—

Svazek periodika

148

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

15

Strana od-do

1901-1915

Kód UT WoS článku

000521585500007

EID výsledku v databázi Scopus

2-s2.0-85083093374