Mathematician Who Tamed Randomness Wins Abel Prize<\/p>\n
Michel Talagrand innovative work has allowed others to tackle problems involving random processes<\/p>\n<\/div>\n
By Davide Castelvecchi<\/a> & Nature magazine<\/a><\/p>\n Michel Talagrand, Abel Prize Laureate, 2024.<\/p>\n<\/div>\n \u00a9 <\/b>Peter Bagde\/Typos1\/Abel Prize 2024<\/p>\n <\/span><\/div>\n<\/figcaption><\/figure>\n<\/div>\n A mathematician who developed formulas to make random processes more predictable and helped to solve an iconic model of complex phenomena has won the 2024 Abel Prize, one of the field\u2019s most coveted awards. Michel Talagrand received the prize for his \u201ccontributions to probability theory and functional analysis, with outstanding applications in mathematical physics and statistics,\u201d the Norwegian Academy of Science and Letters in Oslo announced on 20 March.<\/p>\n Assaf Naor, a mathematician at Princeton University in New Jersey, says it is difficult to overestimate the impact of Talagrand\u2019s work. \u201cThere are papers posted maybe on a daily basis where the punchline is \u2018now we use Talagrand\u2019s inequalities\u2019,\u201d he says.<\/p>\n Talagrand\u2019s reaction on hearing the news was incredulity. \u201cThere was a total blank in my mind for at least four seconds,\u201d he says. \u201cIf I had been told an alien ship had landed in front of the White House, I would not have been more surprised.\u201d<\/p>\n If you’re enjoying this article, consider supporting our award-winning journalism by subscribing<\/a>. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.<\/p>\n The Abel Prize was modelled after the Nobel Prizes \u2014 which do not include mathematics \u2014 and was first awarded in 2003. The recipient wins a sum of 7.5 million Norwegian kroner (US$700,000).<\/p>\n Talagrand specializes in the theory of probability and stochastic processes, which are mathematical models of phenomena governed by randomness. A typical example is a river\u2019s water level, which is highly variable and is affected by many independent factors, including rain, wind and temperature, Talagrand says. His proudest achievement was his inequalities, a set of formulas that poses limits to the swings in stochastic processes. His formulas express how the contributions of many factors often cancel each other out \u2014 making the overall result less variable, not more.<\/p>\n \u201cIt\u2019s like a piece of art,\u201d says Abel-committee chair Helge Holden, a mathematician at the Norwegian University of Science and Technology in Trondheim. \u201cThe magic here is to find a good estimate, not just a rough estimate.\u201d<\/p>\n Thanks to Talagrand\u2019s techniques, \u201cmany things that seem complicated and random turn out to be not so random,\u201d says Naor. His estimates are extremely powerful, for example for studying problems such as optimizing the route of a delivery truck. Finding a perfect solution would require an exorbitant amount of computation, so computer scientists can instead calculate the lengths of a limited number of random candidate routes and then take the average \u2014 and Talagrand\u2019s inequalities ensure that the result is close to optimal.<\/p>\n Talagrand also completed the solution to a problem posed by theoretical physicist Giorgio Parisi \u2014 work that ultimately helped Parisi to earn a Nobel Prize in Physics in 2021. In 1979, Parisi, now at the University of Rome, proposed a complete solution for the structure of a spin glass \u2014 an abstracted model of a material in which the magnetization of each atom tends to flip up or down depending on those of its neighbours.<\/p>\n Parisi\u2019s arguments were rooted in his powerful intuition in physics, and followed steps that \u201cmathematicians would consider as sorcery,\u201d Talagrand says, such as taking n<\/i> copies of a system \u2014 with n<\/i> being a negative number. Many researchers doubted that Parisi\u2019s proof could be made mathematically rigorous. But in the early 2000s, the problem was completely solved in two separate works, one by Talagrand and an earlier one by Francesco Guerra, a mathematical physicist who is also at the University of Rome.<\/p>\n Talagrand\u2019s journey to becoming a top researcher was unconventional. Born in B\u00e9ziers, France, in 1952, he lost vision in his right eye at age five because of a genetic predisposition to detachment of the retina. Although while growing up in Lyon he was a voracious reader of popular science magazines, he struggled at school, particularly with the complex rules of French spelling. \u201cI never really made peace with orthography,\u201d he told an interviewer in 2019<\/a>.<\/p>\n His turning point came at age 15, when he received emergency treatment for another retinal detachment, this time in his left eye. He had to miss almost an entire year of school. The terrifying experience of nearly losing his sight \u2014 and his father\u2019s efforts to keep his mind busy while his eyes were bandaged \u2014 gave Talagrand a renewed focus. He became a highly motivated student after his recovery, and began to excel in national maths competitions.<\/p>\n Still, Talagrand did not follow the typical path of gifted French students, which includes two years of preparatory school followed by a national admission competition for highly selective grandes<\/i> \u00e9coles<\/i> such as the \u00c9cole Normale Sup\u00e9rieure in Paris. Instead, he studied at the University of Lyon, France, and then went on to work as a full-time researcher at the national research agency CNRS, first in Lyon and later in Paris, where he spent more than a decade in an entry-level job. Apart from a brief stint in Canada, followed by a trip to the United States where he met his wife, he worked at the CNRS until his retirement.<\/p>\n Talagrand loves to challenge other mathematicians to solve problems that he has come up with \u2014 offering cash to those who do \u2014 and he keeps a list<\/a> of those problems on his website. Some have been solved, leading to publications in major maths journals<\/a>. The prizes come with some conditions: \u201cI will award the prizes below as long as I am not too senile to understand the proofs I receive. If I can\u2019t understand them, I will not pay.\u201d<\/p>\n This article is reproduced with permission and was <\/i>first published<\/i><\/a> on March 20, 2024<\/i>.<\/p>\n<\/div>\n![\"A](\"https:\/\/static.scientificamerican.com\/dam\/m\/343e96e71cd0ea9c\/original\/Michel_Talagrand_landscape_color_Peter-Badge_Typos1_AbelPrize2024.jpg?w=600\"){kind=icon}
On supporting science journalism<\/h2>\n
\u2018Like a piece of art\u2019<\/h2>\n
Finding motivation<\/h2>\n