it was not until the following morning , when the lack of headlines about his successful experiment took him a little aback-a cluster of suicide bombings in yemen was the main topic of the day , that and the omnipresent y2k speculations : would the world actually come to a standstill at midnight december 31 ? -that he looked at the printouts that covered his desk-now interspersed with congratulatory telexes and emails-and asked himself the same question kristina had asked him , but with added depth : proven what , exactly ?