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John M. Pollard (mathematician)
John M. Pollard (born 1941) is a British mathematician who has invented algorithms for the factorization of large numbers and for the calculation of discrete logarithms. His factorization algorithms include the rho, ''p'' − 1, and the first version of the special number field sieve, which has since been improved by others. His discrete logarithm algorithms include the rho algorithm for logarithms and the kangaroo algorithm. He received the RSA Award for Excellence in Mathematics Formally called since 2025 The RSAC Conference Award for Excellence in Mathematics, is an annual award. It is announced at the annual RSA Conference in recognition of innovations and contributions in the field of cryptography. An award committee o .... External links John Pollard's web site Living people 20th-century British mathematicians 21st-century British mathematicians British number theorists Place of birth missing (living people) 1941 births {{UK-mathematician- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematical model, models, and mathematics#Calculus and analysis, change. History One of the earliest known mathematicians was Thales of Miletus (); he has been hailed as the first true mathematician and the first known individual to whom a mathematical discovery has been attributed. He is credited with the first use of deductive reasoning applied to geometry, by deriving four corollaries to Thales's theorem. The number of known mathematicians grew when Pythagoras of Samos () established the Pythagorean school, whose doctrine it was that mathematics ruled the universe and whose motto was "All is number". It was the Pythagoreans who coined the term "mathematics", and with whom the study of mathematics for its own sake begins. The first woman math ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integer Factorization
In mathematics, integer factorization is the decomposition of a positive integer into a product of integers. Every positive integer greater than 1 is either the product of two or more integer factors greater than 1, in which case it is a composite number, or it is not, in which case it is a prime number. For example, is a composite number because , but is a prime number because it cannot be decomposed in this way. If one of the factors is composite, it can in turn be written as a product of smaller factors, for example . Continuing this process until every factor is prime is called prime factorization; the result is always unique up to the order of the factors by the prime factorization theorem. To factorize a small integer using mental or pen-and-paper arithmetic, the simplest method is trial division: checking if the number is divisible by prime numbers , , , and so on, up to the square root of . For larger numbers, especially when using a computer, various more sophis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discrete Logarithm
In mathematics, for given real numbers a and b, the logarithm \log_b(a) is a number x such that b^x=a. Analogously, in any group G, powers b^k can be defined for all integers k, and the discrete logarithm \log_b(a) is an integer k such that b^k=a. In arithmetic modulo an integer m, the more commonly used term is index: One can write k=\mathbb_b a \pmod (read "the index of a to the base b modulo m") for b^k \equiv a \pmod if b is a primitive root of m and \gcd(a,m)=1. Discrete logarithms are quickly computable in a few special cases. However, no efficient method is known for computing them in general. In cryptography, the computational complexity of the discrete logarithm problem, along with its application, was first proposed in the Diffie–Hellman problem. Several important algorithms in public-key cryptography, such as ElGamal, base their security on the hardness assumption that the discrete logarithm problem (DLP) over carefully chosen groups has no efficient solution. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollard's Rho Algorithm
Pollard's rho algorithm is an algorithm for integer factorization. It was invented by John Pollard in 1975. It uses only a small amount of space, and its expected running time is proportional to the square root of the smallest prime factor of the composite number being factorized. Core ideas The algorithm is used to factorize a number n = pq, where p is a non-trivial factor. A polynomial modulo n, called g(x) (e.g., g(x) = (x^2 + 1) \bmod n), is used to generate a pseudorandom sequence. It is important to note that g(x) must be a polynomial. A starting value, say 2, is chosen, and the sequence continues as x_1 = g(2), x_2 = g(g(2)), x_3 = g(g(g(2))), etc. The sequence is related to another sequence \. Since p is not known beforehand, this sequence cannot be explicitly computed in the algorithm. Yet in it lies the core idea of the algorithm. Because the number of possible values for these sequences is finite, both the \ sequence, which is mod n, and \ sequence will eventually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollard's P − 1 Algorithm
Pollard's ''p'' − 1 algorithm is a number theoretic integer factorization algorithm, invented by John Pollard in 1974. It is a special-purpose algorithm, meaning that it is only suitable for integers with specific types of factors; it is the simplest example of an algebraic-group factorisation algorithm. The factors it finds are ones for which the number preceding the factor, ''p'' − 1, is powersmooth; the essential observation is that, by working in the multiplicative group modulo a composite number ''N'', we are also working in the multiplicative groups modulo all of ''Ns factors. The existence of this algorithm leads to the concept of safe primes, being primes for which ''p'' − 1 is two times a Sophie Germain prime ''q'' and thus minimally smooth. These primes are sometimes construed as "safe for cryptographic purposes", but they might be ''unsafe'' — in current recommendations for cryptographic strong primes (''e.g.' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Special Number Field Sieve
Special or specials may refer to: Policing * Specials, Ulster Special Constabulary, the Northern Ireland police force * Specials, Special Constable, an auxiliary, volunteer, or temporary; police worker or police officer * Special police forces Military * Special forces * Special operations Literature * ''Specials'' (novel), a novel by Scott Westerfeld * ''Specials'', the comic book heroes, see ''Rising Stars'' (comic) Film and television * Special (lighting), a stage light that is used for a single, specific purpose * ''Special'' (film), a 2006 scifi dramedy * ''The Specials'' (2000 film), a comedy film about a group of superheroes * Special 26, a 2013 Indian Hindi-language period heist thriller film * ''The Specials'' (2019 film), a film by Olivier Nakache and Éric Toledano * Television special, television programming that temporarily replaces scheduled programming * ''Special'' (TV series), a 2019 Netflix Original TV series * ''Specials'' (TV series), a 1991 TV seri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollard's Rho Algorithm For Logarithms
Pollard's rho algorithm for logarithms is an algorithm introduced by John Pollard in 1978 to solve the discrete logarithm problem, analogous to Pollard's rho algorithm to solve the integer factorization problem. The goal is to compute \gamma such that \alpha ^ \gamma = \beta, where \beta belongs to a cyclic group G generated by \alpha. The algorithm computes integers a, b, A, and B such that \alpha^a \beta^b = \alpha^A \beta^B. If the underlying group is cyclic of order n, by substituting \beta as ^ and noting that two powers are equal if and only if the exponents are equivalent modulo the order of the base, in this case modulo n, we get that \gamma is one of the solutions of the equation (B-b) \gamma = (a-A) \pmod n. Solutions to this equation are easily obtained using the extended Euclidean algorithm. To find the needed a, b, A, and B the algorithm uses Floyd's cycle-finding algorithm to find a cycle in the sequence x_i = \alpha^ \beta^, where the function f: x_i \mapsto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollard's Kangaroo Algorithm
In computational number theory and computational algebra, Pollard's kangaroo algorithm (also Pollard's lambda algorithm, see Naming below) is an algorithm for solving the discrete logarithm problem. The algorithm was introduced in 1978 by the number theorist John M. Pollard, in the same paper as his better-known Pollard's rho algorithm for solving the same problem. Although Pollard described the application of his algorithm to the discrete logarithm problem in the multiplicative group of units modulo a prime ''p'', it is in fact a generic discrete logarithm algorithm—it will work in any finite cyclic group. Algorithm Suppose G is a finite cyclic group of order n which is generated by the element \alpha, and we seek to find the discrete logarithm x of the element \beta to the base \alpha. In other words, one seeks x \in Z_n such that \alpha^x = \beta. The lambda algorithm allows one to search for x in some interval ,\ldots,bsubset Z_n. One may search the entire range of pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RSA Award For Excellence In Mathematics
Formally called since 2025 The RSAC Conference Award for Excellence in Mathematics, is an annual award. It is announced at the annual RSA Conference in recognition of innovations and contributions in the field of cryptography. An award committee of experts, which is associated with the Cryptographer's Track committee at the RSA Conference (CT-RSA), nominates to the award persons who are pioneers in their field, and whose work has had applied or theoretical lasting value; the award is typically given for the lifetime achievements throughout the nominee's entire career. Nominees are often affiliated with universities or involved with research and development in the information technology industry. The award is cosponsored by the International Association for Cryptologic Research. While the field of modern cryptography started to be an active research area in the 1970s, it has already contributed heavily to Information technology and has served as a critical component in advancing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Living People
Purpose: Because living persons may suffer personal harm from inappropriate information, we should watch their articles carefully. By adding an article to this category, it marks them with a notice about sources whenever someone tries to edit them, to remind them of WP:BLP (biographies of living persons) policy that these articles must maintain a neutral point of view, maintain factual accuracy, and be properly sourced. Recent changes to these articles are listed on Special:RecentChangesLinked/Living people. Organization: This category should not be sub-categorized. Entries are generally sorted by family name In many societies, a surname, family name, or last name is the mostly hereditary portion of one's personal name that indicates one's family. It is typically combined with a given name to form the full name of a person, although several give .... Maintenance: Individuals of advanced age (over 90), for whom there has been no new documentation in the last ten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
21st-century British Mathematicians
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