One of the most important mathematicians of the world, prof. Sir Michael Atiyah, died at the age of 89.
Sir Michael, who worked at the University of Cambridge before retiring, made an outstanding contribution to geometry and topology.
Sir Michael received the highest recognition in mathematics, a Fields Medal. He died Friday
His brother Joe told BBC News that he was one of the most important mathematicians of the twentieth century.
"I was described by more than one mathematics professor as the best mathematician in this country by Sir Isaac Newton," said Atiyah
Sir Michael was also a former president of the Royal Society, which is one of the highest honors a British scientist can receive.
Prof Venki Ramakrishnan, current president of the Royal Society, described him as a "great mathematician".
"Sir Michael Atiyah was also a wonderful person who, as president of the Royal Society, showed he was a true internationalist and a fervent supporter to invest in talent," he added.
Sir Michael was best known for his co-development of a branch of mathematics called K's topological theory and the Atiyah-Singer index theorem.
His research also involved in-depth analysis of mathematical concepts known as "vector packages".
His work in these areas has helped theoretical physicists to advance their understanding of quantum field theory and general relativity.
And he was also an occasional poet ̵
"Sir Michael Atiyah was a dear mentor, a friend and role model, unmatched in intelligence and energy," he said.
"His legacy in mathematics and physics will last forever: his death is a terrible loss, and we extend our deepest condolences to his family.
" He will miss his friends and colleagues all over the world. "