گادفری هارولد هاردی
وی از کالج ترینیتی کمبریج فارغالتحصیل و در (۱۲۷۹ خورشیدی/ ۱۹۰۰ میلادی) به عنوان عضو وابسته برگزیده شد. دیوید هیلبرت در بارهٔ او گفتهاست: «هاردی نه تنها بهترین ریاضیدانان ترینیتی، بلکه بهترین ریاضیدان انگلستان است.» هاردی در سالهای پایانی عمر دست به خودکشی ناموفق زد.
بین سالهای ۱۹۱۱ تا ۱۹۲۲ مقالههای علمی متعدد دربارهٔ همگرایی سلسلهها و انتگرالها و موضوعهای وابسته به آنها منتشر کرد. در ۱۲۸۷/۱۹۰۸ A course of pure Mathematics (دورهای از ریاضیات محض) نخستین نمایش مستدل عدد، تابع، حد و مانند آن به زبان انگلیسی را، برای دانشجویان انتشار داد و آموزش دانشگاهی را متحول کرد. هاردی از سال ۱۹۱۱ تا سی و پنج سال بعد با ج. ا. لیتلوود در زمینه علمی مشارکت کرد و با همکاری وی حدود یکصد مقاله علمی دربارهٔ موضوعاتی از قبیل دیوفانتوسی، نظریه جمع و ضرب اعداد و تابع زتای ریمان، نابرابرها، رشتهها و انتگرالها بهطور عموم و سلسلههای مثلثاتی نوشت. او اثبات کرد تابع زتای ریمان بینهایت صفر دارد. در۱۹۱۳ هاردی با ریاضیدانی هندی به نام سرینیوسه رمنوجن(سرینیواسا رامانوجان) آشنا شد و وی را به انگلستان برد. آندو با هم به راهحلهای جالب مسائل مربوط به دستهبندی اعداد رسیدند. «هاردی بهطور عام بهعنوان دانشمند ممتاز انگلیسی زمان خود در ریاضیات محض شناخته شدهاست.
هرچند هاردی ریاضیدانی ناب بود و کمتر در موضوعی غیر از ریاضیات علاقه نشان میداد و تنها شاید بازی کریکت و اظهار نظرهای حرفهای او در بارهٔ این بازی را بتوان مستثنا کرد اما او در زمینهٔ عقاید سیاسی صلحطلبی رادیکالی بود و در زمان جنگ جهانی دوم علیه جنگ موضع گرفت و دانشمندان را مقصر میدانست او در اثری که در زمان جنگ جهانی دوم منتشر کرد مینویسد: «در مورد جنگ علمی جدید دو نظر دقیقاً متضاد وجود دارد. اولین نظر و واضحترین نظر این است که اثر علم بر جنگ افزایش مصایب آن است، زیرا هم رنجها و آلام اقلیتی را که باید بجنگد بیشتر میکند و هم اینکه جنگ را به سایر قشرها جامعه گسترش میدهد. این نظر، طبیعیترین نظر و دیدگاه متعارف است.» اشتهار او به رادیکال بودن چنان بود که در هنگام تدریس در نیوکالج شایعه شده بود در آپارتمان محل زندگیاش عکس بزرگی از لنین را نصب کردهاست. چالرز پرسیاسنو فیریکدانی که دوست صمیمی هاردی بود در دیباچهٔ کتاب «دفاعیهٔ یک ریاضیدان» مینویسد: «او به آسانی با افراد فقیر، کمرو، و کسانی که به خاطر نژادشان مورد تبعیض بودند (بدون اینکه سرپرستی آنها را به عهده بگیرد) دمخور میشد. (کشف رامانوجان، بازی نمادین سرنوشت او بود) هاردی این قبیل افراد را به شکمگندهها ترجیح میداد. منظورش از شکمگندهها، افراد معروف و مغرور، بورژوا، و طرفدار امپریالیسم بود. این عنوان شامل بیشتر اسقفها، رؤسا و مدیران، قاضیان، و همهٔ سیاستمداران، به استثنای لوید جورج، میشد.»
Godfrey Harold Hardy FRS (7 February 1877 – 1 December 1947) was an English mathematician, known for his achievements in number theory and mathematical analysis. In biology, he is known for the Hardy–Weinberg principle, a basic principle of population genetics. In addition to his research, he is remembered for his 1940 essay on the aesthetics of mathematics, titled A Mathematician's Apology. Hardy also was the mentor of the Indian mathematician Srinivasa Ramanujan.
G. H. Hardy is usually known by those outside the field of mathematics for his essay from 1940 on the aesthetics of mathematics, A Mathematician's Apology, which is often considered one of the best insights into the mind of a working mathematician written for the layperson.
Starting in 1914, Hardy was the mentor of the Indian mathematician Srinivasa Ramanujan, a relationship that has become celebrated. Hardy almost immediately recognised Ramanujan's extraordinary albeit untutored brilliance, and Hardy and Ramanujan became close collaborators. In an interview by Paul Erdős, when Hardy was asked what his greatest contribution to mathematics was, Hardy unhesitatingly replied that it was the discovery of Ramanujan. He called their collaboration "the one romantic incident in my life."
Early life and career
G. H. Hardy was born on 7 February 1877, in Cranleigh, Surrey, England, into a teaching family. His father was Bursar and Art Master at Cranleigh School; his mother had been a senior mistress at Lincoln Training College for teachers. Both parents were mathematically inclined.
Hardy's own natural affinity for mathematics was perceptible at an early age. When just two years old, he wrote numbers up to millions, and when taken to church he amused himself by factorising the numbers of the hymns.
After schooling at Cranleigh, Hardy was awarded a scholarship to Winchester College for his mathematical work. In 1896 he entered Trinity College, Cambridge. After only two years of preparation under his coach, Robert Alfred Herman, Hardy was fourth in the Mathematics Tripos examination. Years later, he sought to abolish the Tripos system, as he felt that it was becoming more an end in itself than a means to an end. While at university, Hardy joined the Cambridge Apostles, an elite, intellectual secret society.
Hardy cited as his most important influence his independent study of Cours d'analyse de l'École Polytechnique by the French mathematician Camille Jordan, through which he became acquainted with the more precise mathematics tradition in continental Europe. In 1900 he passed part II of the Tripos and was duly elected to a college fellowship, a prestigious honor reserved for the top students and one that could last the rest of their lives. In 1903 he earned his M.A., which was the highest academic degree at English universities at that time. From 1906 onward he held the position of a lecturer where teaching six hours per week left him time for research. In 1919 he left Cambridge to take the Savilian Chair of Geometry (and thus become a Fellow of New College) at Oxford in the aftermath of the Bertrand Russell affair during World War I. Hardy spent the academic year 1928–1929 at Princeton in an academic exchange with Oswald Veblen, who spent the year at Oxford. Hardy gave the Josiah Willards Gibbs lecture for 1928. Hardy left Oxford and returned to Cambridge in 1931, where he was Sadleirian Professor until 1942.
Hardy is credited with reforming British mathematics by bringing rigour into it, which was previously a characteristic of French, Swiss and German mathematics. British mathematicians had remained largely in the tradition of applied mathematics, in thrall to the reputation of Isaac Newton (see Cambridge Mathematical Tripos). Hardy was more in tune with the cours d'analyse methods dominant in France, and aggressively promoted his conception of pure mathematics, in particular against the hydrodynamics that was an important part of Cambridge mathematics.
From 1911 he collaborated with John Edensor Littlewood, in extensive work in mathematical analysis and analytic number theory. This (along with much else) led to quantitative progress on Waring's problem, as part of the Hardy–Littlewood circle method, as it became known. In prime number theory, they proved results and some notable conditional results. This was a major factor in the development of number theory as a system of conjectures; examples are the first and second Hardy–Littlewood conjectures. Hardy's collaboration with Littlewood is among the most successful and famous collaborations in mathematical history. In a 1947 lecture, the Danish mathematician Harald Bohr reported a colleague as saying, "Nowadays, there are only three really great English mathematicians: Hardy, Littlewood, and Hardy–Littlewood.":xxvii
Hardy is also known for formulating the Hardy–Weinberg principle, a basic principle of population genetics, independently from Wilhelm Weinberg in 1908. He played cricket with the geneticist Reginald Punnett who introduced the problem to him, and Hardy thus became the somewhat unwitting founder of a branch of applied mathematics.
Hardy preferred his work to be considered pure mathematics, perhaps because of his detestation of war and the military uses to which mathematics had been applied. He made several statements similar to that in his Apology:
However, aside from formulating the Hardy–Weinberg principle in population genetics, his famous work on integer partitions with his collaborator Ramanujan, known as the Hardy–Ramanujan asymptotic formula, has been widely applied in physics to find quantum partition functions of atomic nuclei (first used by Niels Bohr) and to derive thermodynamic functions of non-interacting Bose–Einstein systems. Though Hardy wanted his maths to be "pure" and devoid of any application, much of his work has found applications in other branches of science.
Moreover, Hardy deliberately pointed out in his Apology that mathematicians generally do not "glory in the uselessness of their work," but rather – because science can be used for evil ends as well as good – "mathematicians may be justified in rejoicing that there is one science at any rate, and that their own, whose very remoteness from ordinary human activities should keep it gentle and clean.":33 Hardy also rejected as a "delusion" the belief that the difference between pure and applied mathematics had anything to do with their utility. Hardy regards as "pure" the kinds of mathematics that are independent of the physical world, but also considers some "applied" mathematicians, such as the physicists Maxwell and Einstein, to be among the "real" mathematicians, whose work "has permanent aesthetic value" and "is eternal because the best of it may, like the best literature, continue to cause intense emotional satisfaction to thousands of people after thousands of years." Although he admitted that what he called "real" mathematics may someday become useful, he asserted that, at the time in which the Apology was written, only the "dull and elementary parts" of either pure or applied mathematics could "work for good or ill.":39
Attitudes and personality
Socially, Hardy was associated with the Bloomsbury group and the Cambridge Apostles; G. E. Moore, Bertrand Russell and J. M. Keynes were friends. He was an avid cricket fan. Maynard Keynes observed that if Hardy had read the stock exchange for half an hour every day with as much interest and attention as he did the day's cricket scores, he would have become a rich man.
Hardy was an atheist. Apart from close friendships, he had a few platonic relationships with young men who shared his sensibilities, and often his love of cricket. A mutual interest in cricket led him to befriend the young C. P. Snow. Hardy was a lifelong bachelor and in his final years he was cared for by his sister.
Hardy was extremely shy as a child, and was socially awkward, cold and eccentric throughout his life. During his school years he was top of his class in most subjects, and won many prizes and awards but hated having to receive them in front of the entire school. He was uncomfortable being introduced to new people, and could not bear to look at his own reflection in a mirror. It is said that, when staying in hotels, he would cover all the mirrors with towels.
Hardy is a key character, played by Jeremy Irons, in the 2015 film The Man Who Knew Infinity, based on the biography of Ramanujan with the same title. Hardy is a major character in David Leavitt's fictive biography, The Indian Clerk (2007), which depicts his Cambridge years and his relationship with John Edensor Littlewood and Ramanujan. Hardy is a secondary character in Uncle Petros and Goldbach's Conjecture (1992), a mathematics novel by Apostolos Doxiadis.