Cem Yıldırım
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Cem Yıldırım
Cem Yalçın Yıldırım (born 8 July 1961) is a Turkish mathematician who specializes in number theory. He obtained his B.Sc from Middle East Technical University in Ankara, Turkey and his PhD from the University of Toronto in 1990. His advisor was John Friedlander. He is currently a faculty member at Boğaziçi University in Istanbul, Turkey. In 2005(), with Dan Goldston and János Pintz, he proved, that for any positive number ''ε'' there exist primes ''p'' and ''p''′ such that the difference between ''p'' and ''p''′ is smaller than ''ε'' log ''p''. Formally; :\liminf_\frac=0 where ''p''''n'' denotes the ''n''th prime number. In other words, for every ''c'' > 0, there exist infinitely many pairs of consecutive primes ''p''''n'' and ''p''''n''+1 which are closer to each other than the average distance between consecutive primes by a factor of ''c'', i.e., ''p''''n''+1 − ''p''''n'' < ''c'' log ''p''''n''. This r ...
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Republic Of Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with a East Thrace, small portion on the Balkans, Balkan Peninsula in Southeast Europe. It shares borders with the Black Sea to the north; Georgia (country), Georgia to the northeast; Armenia, Azerbaijan, and Iran to the east; Iraq to the southeast; Syria and the Mediterranean Sea to the south; the Aegean Sea to the west; and Greece and Bulgaria to the northwest. Cyprus is located off the south coast. Turkish people, Turks form the vast majority of the nation's population and Kurds are the largest minority. Ankara is Turkey's capital, while Istanbul is its list of largest cities and towns in Turkey, largest city and financial centre. One of the world's earliest permanently Settler, settled regions, present-day Turkey was home to important Neol ...
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Prime Number
A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, or , involve 5 itself. However, 4 is composite because it is a product (2 × 2) in which both numbers are smaller than 4. Primes are central in number theory because of the fundamental theorem of arithmetic: every natural number greater than 1 is either a prime itself or can be factorized as a product of primes that is unique up to their order. The property of being prime is called primality. A simple but slow method of checking the primality of a given number n, called trial division, tests whether n is a multiple of any integer between 2 and \sqrt. Faster algorithms include the Miller–Rabin primality test, which is fast but has a small chance of error, and the AKS primality test, which always pr ...
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Number Theorists
Number theory (or arithmetic or higher arithmetic in older usage) is a branch of pure mathematics devoted primarily to the study of the integers and integer-valued functions. German mathematician Carl Friedrich Gauss (1777–1855) said, "Mathematics is the queen of the sciences—and number theory is the queen of mathematics."German original: "Die Mathematik ist die Königin der Wissenschaften, und die Arithmetik ist die Königin der Mathematik." Number theorists study prime numbers as well as the properties of mathematical objects made out of integers (for example, rational numbers) or defined as generalizations of the integers (for example, algebraic integers). Integers can be considered either in themselves or as solutions to equations (Diophantine geometry). Questions in number theory are often best understood through the study of analytical objects (for example, the Riemann zeta function) that encode properties of the integers, primes or other number-theoretic objects in ...
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Living People
Related categories * :Year of birth missing (living people) / :Year of birth unknown * :Date of birth missing (living people) / :Date of birth unknown * :Place of birth missing (living people) / :Place of birth unknown * :Year of death missing / :Year of death unknown * :Date of death missing / :Date of death unknown * :Place of death missing / :Place of death unknown * :Missing middle or first names See also * :Dead people * :Template:L, which generates this category or death years, and birth year and sort keys. : {{DEFAULTSORT:Living people 21st-century people People by status ...
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1961 Births
Events January * January 3 ** United States President Dwight D. Eisenhower announces that the United States has severed diplomatic and consular relations with Cuba ( Cuba–United States relations are restored in 2015). ** Aero Flight 311 (Koivulahti air disaster): Douglas DC-3C OH-LCC of Finnish airline Aero crashes near Kvevlax (Koivulahti), on approach to Vaasa Airport in Finland, killing all 25 on board, due to pilot error: an investigation finds that the captain and first officer were both exhausted for lack of sleep, and had consumed excessive amounts of alcohol at the time of the crash. It remains the deadliest air disaster to occur in the country. * January 5 ** Italian sculptor Alfredo Fioravanti marches into the U.S. Consulate in Rome, and confesses that he was part of the team that forged the Etruscan terracotta warriors in the Metropolitan Museum of Art. ** After the 1960 military coup, General Cemal Gürsel forms the new government of Turkey (25th gove ...
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21st-century Turkish Mathematicians
The 1st century was the century spanning AD 1 ( I) through AD 100 ( C) according to the Julian calendar. It is often written as the or to distinguish it from the 1st century BC (or BCE) which preceded it. The 1st century is considered part of the Classical era, epoch, or historical period. The 1st century also saw the appearance of Christianity. During this period, Europe, North Africa and the Near East fell under increasing domination by the Roman Empire, which continued expanding, most notably conquering Britain under the emperor Claudius (AD 43). The reforms introduced by Augustus during his long reign stabilized the empire after the turmoil of the previous century's civil wars. Later in the century the Julio-Claudian dynasty, which had been founded by Augustus, came to an end with the suicide of Nero in AD 68. There followed the famous Year of Four Emperors, a brief period of civil war and instability, which was finally brought to an end by Vespasian, ninth Roman emperor, a ...
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Landau's Problems
At the 1912 International Congress of Mathematicians, Edmund Landau listed four basic problems about prime numbers. These problems were characterised in his speech as "unattackable at the present state of mathematics" and are now known as Landau's problems. They are as follows: # Goldbach's conjecture: Can every even integer greater than 2 be written as the sum of two primes? # Twin prime conjecture: Are there infinitely many primes ''p'' such that ''p'' + 2 is prime? # Legendre's conjecture: Does there always exist at least one prime between consecutive perfect squares? # Are there infinitely many primes ''p'' such that ''p'' − 1 is a perfect square? In other words: Are there infinitely many primes of the form ''n''2 + 1? , all four problems are unresolved. Progress toward solutions Goldbach's conjecture Goldbach's weak conjecture, every odd number greater than 5 can be expressed as the sum of three primes, is a consequence of Goldb ...
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Twin Prime
A twin prime is a prime number that is either 2 less or 2 more than another prime number—for example, either member of the twin prime pair (41, 43). In other words, a twin prime is a prime that has a prime gap of two. Sometimes the term ''twin prime'' is used for a pair of twin primes; an alternative name for this is prime twin or prime pair. Twin primes become increasingly rare as one examines larger ranges, in keeping with the general tendency of gaps between adjacent primes to become larger as the numbers themselves get larger. However, it is unknown whether there are infinitely many twin primes (the so-called twin prime conjecture) or if there is a largest pair. The breakthrough work of Yitang Zhang in 2013, as well as work by James Maynard, Terence Tao and others, has made substantial progress towards proving that there are infinitely many twin primes, but at present this remains unsolved. Properties Usually the pair (2, 3) is not considered to be a pair of twin primes. ...
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Elliott–Halberstam Conjecture
In number theory, the Elliott–Halberstam conjecture is a conjecture about the distribution of prime numbers in arithmetic progressions. It has many applications in sieve theory. It is named for Peter D. T. A. Elliott and Heini Halberstam, who stated the conjecture in 1968. Stating the conjecture requires some notation. Let \pi(x), the prime-counting function, denote the number of primes less than or equal to x. If q is a positive integer and a is coprime to q, we let \pi(x;q,a) denote the number of primes less than or equal to x which are equal to a modulo q. Dirichlet's theorem on primes in arithmetic progressions then tells us that : \pi(x;q,a) \approx \frac where \varphi is Euler's totient function. If we then define the error function : E(x;q) = \max_ \left, \pi(x;q,a) - \frac\ where the max is taken over all a coprime to q, then the Elliott–Halberstam conjecture is the assertion that for every \theta 0 there exists a constant C > 0 such that : \sum_ E(x;q) \le ...
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János Pintz
János Pintz (born 20 December 1950 in Budapest) is a Hungary, Hungarian mathematician working in analytic number theory. He is a fellow of the Alfréd Rényi Institute of Mathematics, Rényi Mathematical Institute and is also a member of the Hungarian Academy of Sciences. In 2014, he received the Cole Prize. Mathematical results Pintz is best known for proving in 2005 (with Daniel Goldston and Cem Yıldırım) that :: \liminf_\frac=0 where p_n denotes the ''n''th prime number. In other words, for every ε > 0, there exist infinitely many pairs of consecutive primes ''p''''n'' and ''p''''n''+1 that are closer to each other than the average distance between consecutive primes by a factor of ε, i.e., ''p''''n''+1 − ''p''''n'' < ε log ''p''''n''. This result was originally reported in 2003 by Daniel Goldston and Cem Yıldırım but was later retracted. Pintz joined the team and comple ...
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Bilkent University
Bilkent University ( tr, Bilkent Üniversitesi) is a private university located in Ankara, Turkey. It was founded by Prof. İhsan Doğramacı in 1984, with the aim of creating a center of excellence in higher education and research. It is constantly ranked among the top Turkish universities since its establishment. In 2011, it was listed as the top 112th university in the world by The World University Rankings. Bilkent University was modeled after Harvard University and was the first non-profit private university established in the country. The name Bilkent is an abbreviation of ''bilim kenti'': Turkish for "city of science". History Preparations for the establishment of the university began in 1967, with the purchase of a tract of land to the west of Ankara. In the late 1970s the foundations of the buildings which now house administrative offices, the faculty of engineering, and the library, were laid. Construction of residences for academic staff, cafeterias, student dormitori ...
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