With my plane Lelystad


With R. Kerr 2018
With R. Penrose 2016

Conference Utrecht 2019, in honour of 20-year celebration of Nobel-prize of G.’t Hooft

MG15, Rome 2015

Timemachine factory conference Torino, 2019

With Y.Choquet-Bruhat 2018 Rome
Aveiro workshop 2017
PhD defence 1986. Opposition G.’t Hooft
With Paul Davies, Poland 2016