Meetings with A.V.Skorokhod
 
With great sorrow I learnt of the decease of Anatolii Vladimirovich Skorokhod, to whom I am much obliged. As for many other mathematicians related to probability theory, my acquaintance with him began with reading his books. I remember very well as I was thoroughly studying the first volume of Gihman--Skorokhod in the fall of 1980 during compulsory students work at an agricultural enterprize (``kolkhoz''), often falling asleep with this book after a hard working day. A bit later I got acquainted  with ``Integration in Hilbert space''. I do not remember precisely when I first saw Skorokhod personally (possibly, this happened when he was speaking at our Department of Mechanics and Mathematics of Moscow Lomonosov University in the quality of a referee at habilitations of A.D. Wentzel and S.A. Molchanov), but in June of 1984 along with another PhD student I was asked to meet Anatolii Vladimirovich at the Vnukovo airport in Moscow and that time I made his personal acquaintance; this was accompanied by some embarrassment: the taxi fare from the airport to the city was, in our opinion, incredibly expensive (it seems, amounting to 10 roubles), so we took Skorokhod to a municipal bus, but his reaction was: ``do not worry, guys,  I'll bring you there by taxi'', so that in the result it remained unclear who and  whom was meeting.
Our next meeting took place at the Vilnius international conference in 1985, and I was extremely  happy that Anatolii Vladimirovich recognized me; in addition, he invited me to give a talk at his seminar in Kiev. A consequence of that was that he also wrote  a report on my PhD dissertation on behalf of the Institute of Mathematics of the Ukrainian Academy of Science (a~report of an organization was required along with two reports of referees). It should be noted that at the time a talk at the Skorokhod seminar was regarded as a very prestigious event for the speaker. This  seminar was one of the leading ones in probability not only in the USSR, but, I believe, also in the world.  An impressive feature of the seminar was the presence  of a large number of young professors with habilitation among the Kiev participants, a quite rare phenomenon at the epoch. To pick up Skorokhod's report, I arrived in May of 1986, soon after the Chernobyl catastrophe;I remember desert Kiev streets; strawberry was offered almost free in Kiev markets, but nobody wanted to take, and Skorokhod advised to drink red wine (it was believed to  help somehow against radiation).

In the subsequent years I was keeping regular contacts with Anatolii Vladimirovich in Kiev and Moscow. So he was the first to whom I addressed 3 years later, in 1989, asking to be a referee for my doctoral dissertation (habilitation). At the time Skorokhod was often invited as a referee for habilitations not only because he was one of the top experts in probability, but also due to his reputation of being an absolutely independent person, which would take his decision according to his opinion of the work without any political considerations. Various political considerations played a very important  role (sometimes a major role) in defences of habilitations. In particular, in my case, the situation was rather complicated, because after finishing PhD studies and defending my PhD dissertation in 1986, I got only a temporary position at our department, so during the next 3 years I had to renew my contract every year. A habilitation could significantly increase my chances to get a permanent position, but it turned out to be a rather difficult problem to arrange my defence.
Here I received a very essential help from Skorokhod. When inviting him to be a referee, I informed him of the existing difficulties, but, having learned of them, he was not bothered at all and assured me that such a thing was quite usual; in addition, he said that he was ready to be a referee in any scientific council which would accept my habilitation for consideration; moreover, he told me that I could apply to their council in Kiev, but nevertheless advised to struggle for defence at our department council, which I finally managed to do 2 years later.
In June of 1991 I spent the whole day of my habilitation defence together with Anatolii Vladimirovich; from the very morning, when I was again meeting him at the airport (but this time I was clever enough to get a taxi) until the late evening, when after a friendly dinner at our home he was returning to Kiev by train. That day we talked a lot on many subjects, not only on mathematics; I often remember these conversations when taking one of his many books on my bookshelf. In the introduction to one of these books, remembering Gikhman, Skorokhod wrote:  “would like to honour the memory of my teacher and friend at least by this choice of the subject”. No doubt that many mathematicians will honour the memory of Skorokhod by their choice of the subject of research; this will be definitely done also at our Mehmat seminar “Infinite dimensional analysis and stochastics”, where we frequently  pronounce his name, the name of a classic in probability theory and a generous man with an open heart.

V. Bogachev
Moscow State Lomonosov University