Warning: Table './church/sessions' is marked as crashed and last (automatic?) repair failed
query: SELECT sid FROM sessions WHERE sid = 'cfjllfmvvk3g8hgtbm739uf0r6' in /var/www/church/includes/database.mysql.inc on line 121 Gruppo di Logica e Geometria della Cognizione
Dipartimento di Matematica e Fisica, Aula 311
Largo San Leonardo Murialdo, 1
Abstract
Discovered (or invented?) by Richard Laver in the 1990s, the tables that are now known as Laver tables are finite structures obeying the self-distributivity law x(yz)=(xy)(xz). Although their construction is totally explicit, some of their combinatorial properties are (so far) established only using unprovable set theoretical axioms, a quite unusual and paradoxical situation. We shall explain the construction of Laver tables, their connection with set theory, and their potential applications in low-dimensional topology via the recent computation of some associated cocycles.
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query: INSERT INTO watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table './church/sessions' is marked as crashed and last (automatic?) repair failed\nquery: SELECT sid FROM sessions WHERE sid = 'cfjllfmvvk3g8hgtbm739uf0r6' in /var/www/church/includes/database.mysql.inc on line 121.', 2, '', 'http://logica.uniroma3.it/calendario/2017/2/17', '', '216.73.216.58', 1751701166) in /var/www/church/includes/database.mysql.inc on line 121
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query: INSERT INTO watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (0, 'php', 'Table './church/sessions' is marked as crashed and last (automatic?) repair failed\nquery: INSERT INTO sessions (sid, uid, cache, hostname, session, timestamp) VALUES ('cfjllfmvvk3g8hgtbm739uf0r6', 0, 0, '216.73.216.58', 'calendar_year|i:2017;calendar_mon|i:2;', 1751701166) in /var/www/church/includes/database.mysql.inc on line 121.', 2, '', 'http://logica.uniroma3.it/calendario/2017/2/17', '', '216.73.216.58', 1751701166) in /var/www/church/includes/database.mysql.inc on line 121