2014 Cole Prize in Number Theory
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A Note on the Origin of the Twin Prime Conjecture
A Note on the Origin of the Twin Prime Conjecture by William Dunham Department of Mathematics & Computer Science, Muhlenberg College; Department of Mathematics, Harvard University (visiting 2012-2013) More than any other branch of mathematics, number As the title suggests, de Polignac’s paper was about theory features a collection of famous problems that took prime numbers, and on p. 400 he stated two “theorems.” centuries to be proved or that remain unresolved to the It should be noted that he was not using the word in its present day. modern sense. Rather, de Polignac confirmed the truth of Among the former is Fermat’s Last Theorem. This these results by checking a number of cases and thereby states that it is impossible to find a whole number n ≥ 3 called them “theorems.” Of course, we would call them, at and whole numbers x , y , and z for which xn + yn = zn . best, “conjectures.” The true nature of these statements is suggested by the fact that de Polignac introduced them In 1640, as all mathematicians know, Fermat wrote this in under the heading “Induction and remarks” as seen below, a marginal note and claimed to have “an admirable proof” in a facsimile of his original text. that, alas, did not fit within the space available. The result remained unproved for 350 years until Andrew Wiles, with assistance from Richard Taylor, showed that Fermat was indeed correct. On the other hand, there is the Goldbach conjecture, which asserts that every even number greater than 2 can be expressed as the sum of two primes. -
Sieve Theory and Small Gaps Between Primes: Introduction
Sieve theory and small gaps between primes: Introduction Andrew V. Sutherland MASSACHUSETTS INSTITUTE OF TECHNOLOGY (on behalf of D.H.J. Polymath) Explicit Methods in Number Theory MATHEMATISCHES FORSCHUNGSINSTITUT OBERWOLFACH July 6, 2015 A quick historical overview pn+m − pn ∆m := lim inf Hm := lim inf (pn+m − pn) n!1 log pn n!1 Twin Prime Conjecture: H1 = 2 Prime Tuples Conjecture: Hm ∼ m log m 1896 Hadamard–Vallee´ Poussin ∆1 ≤ 1 1926 Hardy–Littlewood ∆1 ≤ 2=3 under GRH 1940 Rankin ∆1 ≤ 3=5 under GRH 1940 Erdos˝ ∆1 < 1 1956 Ricci ∆1 ≤ 15=16 1965 Bombieri–Davenport ∆1 ≤ 1=2, ∆m ≤ m − 1=2 ········· 1988 Maier ∆1 < 0:2485. 2005 Goldston-Pintz-Yıldırım ∆1 = 0, ∆m ≤ m − 1, EH ) H1 ≤ 16 2013 Zhang H1 < 70; 000; 000 2013 Polymath 8a H1 ≤ 4680 3 4m 2013 Maynard-Tao H1 ≤ 600, Hm m e , EH ) H1 ≤ 12 3:815m 2014 Polymath 8b H1 ≤ 246, Hm e , GEH ) H1 ≤ 6 H2 ≤ 398; 130, H3 ≤ 24; 797; 814,... The prime number theorem in arithmetic progressions Define the weighted prime counting functions1 X X Θ(x) := log p; Θ(x; q; a) := log p: prime p ≤ x prime p ≤ x p ≡ a mod q Then Θ(x) ∼ x (the prime number theorem), and for a ? q, x Θ(x; q; a) ∼ : φ(q) We are interested in the discrepancy between these two quantities. −x x x Clearly φ(q) ≤ Θ(x; q; a) − φ(q) ≤ q + 1 log x, and for any Q < x, X x X 2x log x x max Θ(x; q; a) − ≤ + x(log x)2: a?q φ(q) q φ(q) q ≤ Q q≤Q 1 P One can also use (x) := n≤x Λ(n), where Λ(n) is the von Mangoldt function. -
Dr. Yitang Zhang Professor Department of Mathematics University of California, Santa Barbara
Distinguished Lifetime Achievement Award Dr. Yitang Zhang Professor Department of Mathematics University of California, Santa Barbara Citation of Accomplishments Establishing the first finite bound on the gaps of prime numbers and thus solving a centuries- old problem in number theory, and his unsubdued passion for mathematics and science. Dr. Yitang Zhang was born on February 5, 1955 in Shanghai, China, and lived there until he was 13 years old. During the Cultural Revolution, he and his parents were sent to the countryside to work in the fields. He worked as a laborer for ten years and was unable to attend high school. After the Cultural Revolution ended, he entered Peking University in 1978 as an undergraduate student and graduated in 1982. Then he became a graduate student of Professor Pan Chengbiao, a number theorist at Peking University, and obtained his master’s degree in mathematics in 1984. With recommendations from Professor Ding Shisun, the president of Peking University, Yitang was granted a full scholarship at Purdue University. He arrived at Purdue in June 1985, studied there for seven years, and obtained his Ph.D. in mathematics in December 1991. After graduation, he had a hard time finding an academic position. After several years, he managed to find a position as a lecturer at the University of New Hampshire (UNH), where he was hired by Professor Kenneth Appel in 1999. He served as a lecturer at UNH until January 2014, when UNH appointed him to a full professorship as a result of his breakthrough on the distribution of prime numbers. In Fall 2015, he accepted an offer of full professorship at the University of California, Santa Barbara. -
Fundamental Theorems in Mathematics
SOME FUNDAMENTAL THEOREMS IN MATHEMATICS OLIVER KNILL Abstract. An expository hitchhikers guide to some theorems in mathematics. Criteria for the current list of 243 theorems are whether the result can be formulated elegantly, whether it is beautiful or useful and whether it could serve as a guide [6] without leading to panic. The order is not a ranking but ordered along a time-line when things were writ- ten down. Since [556] stated “a mathematical theorem only becomes beautiful if presented as a crown jewel within a context" we try sometimes to give some context. Of course, any such list of theorems is a matter of personal preferences, taste and limitations. The num- ber of theorems is arbitrary, the initial obvious goal was 42 but that number got eventually surpassed as it is hard to stop, once started. As a compensation, there are 42 “tweetable" theorems with included proofs. More comments on the choice of the theorems is included in an epilogue. For literature on general mathematics, see [193, 189, 29, 235, 254, 619, 412, 138], for history [217, 625, 376, 73, 46, 208, 379, 365, 690, 113, 618, 79, 259, 341], for popular, beautiful or elegant things [12, 529, 201, 182, 17, 672, 673, 44, 204, 190, 245, 446, 616, 303, 201, 2, 127, 146, 128, 502, 261, 172]. For comprehensive overviews in large parts of math- ematics, [74, 165, 166, 51, 593] or predictions on developments [47]. For reflections about mathematics in general [145, 455, 45, 306, 439, 99, 561]. Encyclopedic source examples are [188, 705, 670, 102, 192, 152, 221, 191, 111, 635]. -
A Friendly Intro to Sieves with a Look Towards Recent Progress on the Twin Primes Conjecture
A FRIENDLY INTRO TO SIEVES WITH A LOOK TOWARDS RECENT PROGRESS ON THE TWIN PRIMES CONJECTURE DAVID LOWRY-DUDA This is an extension and background to a talk I gave on 9 October 2013 to the Brown Graduate Student Seminar, called `A friendly intro to sieves with a look towards recent progress on the twin primes conjecture.' During the talk, I mention several sieves, some with a lot of detail and some with very little detail. I also discuss several results and built upon many sources. I'll provide missing details and/or sources for additional reading here. Furthermore, I like this talk, so I think it's worth preserving. 1. Introduction We talk about sieves and primes. Long, long ago, Euclid famously proved the in- finitude of primes (≈ 300 B.C.). Although he didn't show it, the stronger statement that the sum of the reciprocals of the primes diverges is true: X 1 ! 1; p p where the sum is over primes. Proof. Suppose that the sum converged. Then there is some k such that 1 X 1 1 < : pi 2 i=k+1 Qk Suppose that Q := i=1 pi is the product of the primes up to pk. Then the integers 1 + Qn are relatively prime to the primes in Q, and so are only made up of the primes pk+1;:::. This means that 1 !t X 1 X X 1 ≤ < 2; 1 + Qn pi n=1 t≥0 i>k where the first inequality is true since all the terms on the left appear in the middle (think prime factorizations and the distributive law), and the second inequality is true because it's bounded by the geometric series with ratio 1=2. -
Ten Mathematical Landmarks, 1967–2017
Ten Mathematical Landmarks, 1967{2017 MD-DC-VA Spring Section Meeting Frostburg State University April 29, 2017 Ten Mathematical Landmarks, 1967{2017 Nine, Eight, Seven, and Six Nine: Chaos, Fractals, and the Resurgence of Dynamical Systems Eight: The Explosion of Discrete Mathematics Seven: The Technology Revolution Six: The Classification of Finite Simple Groups Ten Mathematical Landmarks, 1967{2017 Five: The Four-Color Theorem 1852-1976 1852: Francis Guthrie's conjecture: Four colors are sufficient to color any map on the plane in such a way that countries sharing a boundary edge (not merely a corner) must be colored differently. 1878: Arthur Cayley addresses the London Math Society, asks if the Four-Color Theorem has been proved. 1879: A. B. Kempe publishes a proof. 1890: P. J. Heawood notes that Kempe's proof has a serious gap in it, uses same method to prove the Five-Color Theorem for planar maps. The Four-Color Conjecture remains open. 1891: Heawood makes a conjecture about coloring maps on the surfaces of many-holed tori. 1900-1950's: Many attempts to prove the 4CC (Franklin, George Birkhoff, many others) give a jump-start to a certain branch of topology called Graph Theory. The latter becomes very popular. Ten Mathematical Landmarks, 1967{2017 Five: The Four-Color Theorem (4CT) The first proof By the early 1960s, the 4CC was proved for all maps with at most 38 regions. In 1969, H. Heesch developed the two main ingredients needed for the ultimate proof, namely reducibility and discharging. He also introduced the idea of an unavoidable configuration. -
Awards of ICCM 2013 by the Editors
Awards of ICCM 2013 by the Editors academies of France, Sweden and the United States. He is a recipient of the Fields Medal (1986), the Crafoord Prize Morningside Medal of Mathematics in Mathematics (1994), the King Faisal International Prize Selection Committee for Science (2006), and the Shaw Prize in Mathematical The Morningside Medal of Mathematics Selection Sciences (2009). Committee comprises a panel of world renowned mathematicians and is chaired by Professor Shing-Tung Björn Engquist Yau. A nomination committee of around 50 mathemati- Professor Engquist is the Computational and Applied cians from around the world nominates candidates based Mathematics Chair Professor at the University of Texas at on their research, qualifications, and curriculum vitae. Austin. His recent work includes homogenization theory, The Selection Committee reviews these nominations and multi-scale methods, and fast algorithms for wave recommends up to two recipients for the Morningside propagation. He is a member of the Royal Swedish Gold Medal of Mathematics, up to two recipients for the Morningside Gold Medal of Applied Mathematics, and up to four recipients for the Morningside Silver Medal of Mathematics. The Selection Committee members, with the exception of the committee chair, are all non-Chinese to ensure the independence, impartiality and integrity of the awards decision. Members of the 2013 Morningside Medal of Mathe- matics Selection Committee are: Richard E. Borcherds Professor Borcherds is Professor of Mathematics at the University of California at Berkeley. His research in- terests include Lie algebras, vertex algebras, and auto- morphic forms. He is best known for his work connecting the theory of finite groups with other areas in mathe- matics. -
NUMBER THEORY and COMBINATORICS SEMINAR UNIVERSITY of LETHBRIDGE Contents
PAST SPEAKERS IN THE NUMBER THEORY AND COMBINATORICS SEMINAR OF THE DEPARTMENT OF MATHEMATICS & COMPUTER SCIENCE AT THE UNIVERSITY OF LETHBRIDGE http://www.cs.uleth.ca/~nathanng/ntcoseminar/ Organizers: Nathan Ng and Dave Witte Morris (starting Fall 2011) Amir Akbary (Fall 2007 – Fall 2010) Contents ........................... Fall 2020 2 Spring 2014 ....................... 48 ........................ Spring 2020 5 Fall 2013 .......................... 52 ........................... Fall 2019 9 Spring 2013 ....................... 55 ....................... Spring 2019 12 Fall 2012 .......................... 59 .......................... Fall 2018 16 Spring 2012 ....................... 63 ....................... Spring 2018 20 Fall 2011 .......................... 67 .......................... Fall 2017 24 Fall 2010 .......................... 70 ....................... Spring 2017 28 Spring 2010 ....................... 71 .......................... Fall 2016 31 Fall 2009 .......................... 73 ....................... Spring 2016 34 Spring 2009 ....................... 75 .......................... Fall 2015 39 Fall 2008 .......................... 77 ....................... Spring 2015 42 Spring 2008 ....................... 80 .......................... Fall 2014 45 Fall 2007 .......................... 83 Fall 2020 Open problem session Sep 28, 2020 Please bring your favourite (math) problems. Anyone with a problem to share will be given about 5 minutes to present it. We will also choose most of the speakers for the rest of the semester. -
Small Gaps Between Three Almost Primes and Almost Prime Powers
SMALL GAPS BETWEEN THREE ALMOST PRIMES AND ALMOST PRIME POWERS DANIEL A. GOLDSTON, APOORVA PANIDAPU, AND JORDAN SCHETTLER Abstract. A positive integer is called an Ej -number if it is the product of j distinct primes. We prove that there are infinitely many triples of E2-numbers within a gap size of 32 and infinitely many triples of E3-numbers within a gap size of 15. Assuming the Elliot-Halberstam conjecture for primes and E2- numbers, we can improve these gaps to 12 and 5, respectively. We can obtain even smaller gaps for almost primes, almost prime powers, or integers having the same exponent pattern in the their prime factorizations. In particular, if d(x) denotes the number of divisors of x, we prove that there are integers a, b with 1 ≤ a < b ≤ 9 such that d(x) = d(x + a) = d(x + b) = 192 for infinitely many x. Assuming Elliot-Halberstam, we prove that there are integers a, b with 1 ≤ a < b ≤ 4 such that d(x) = d(x + a) = d(x + b) = 24 for infinitely many x. 1. Introduction For our purposes, an almost prime or almost prime power will refer to a positive integer with some fixed small number of prime factors counted with or without multiplicity, respectively. Small gaps between primes and almost primes became a popular subject of research following the results of the GPY sieve [GPY09] and Yitang Zhang’s subsequent proof of bounded gaps between primes [Zha14]. For a positive integer x, let Ω(x) denote the number of prime factors of x counted with multiplicity, and let ω(x) denote the number of prime factors of x counted without multiplicity, i.e., ω(x) is the number of distinct primes dividing x. -
Citation for Yitang Zhang the Ostrowski Prize for 2013 Is Awarded to Professor Yitang Zhang for His Breakthrough Work on Small Gaps Between Prime Numbers
Citation for Yitang Zhang The Ostrowski Prize for 2013 is awarded to Professor Yitang Zhang for his breakthrough work on small gaps between prime numbers. Yitang Zhang was granted a Bachelor's degree in 1982 and a Master's degree in 1985 from Peking University. He then travelled to the United States for further graduate work and in 1991 obtained a Ph.D. degree from Purdue University. In 1999 he joined the Department of Mathematics at the University of New Hampshire, where he remains to this day. Professor Zhang's work deals with a fundamental question about the dis- tribution of prime numbers.Let us put it in a historical context. Let p1; p2;::: denote the increasing sequence of prime numbers. It follows from the prime number theorem that the average gap between consecutive prime numbers pn+1 and pn is roughly log pn in size. What can be said about small gaps between consecutive primes? Erd}os,in 1940, was the first to prove that there is a positive number c which is smaller than 1 such that pn+1 − pn < c log pn (1) for infinitely many positive integers n: This result was refined by Bombieri and Davenport, Huxley, Maier and others. In particular, Maier proved that (1) holds with c = :248 ::: in 1988. Next Goldston, Pintz and Yildirim established, in a pair of papers which appeared in 2009 and 2010, that a much stronger result is true. They proved that there is a positive number C such that 1=2 2 pn+1 − pn < C(log pn) (log log pn) for infinitely many positive integers n: Building on the work of Goldston, Pintz and Yildirim, Zhang proved in 2013 that 7 pn+1 − pn < 7 · 10 for infinitely many positive integers n: This represents a stunning step for- ward and brings the twin prime conjecture into view. -
The Non-Publishability Theorem of the Proof of Goldbach's Conjecture A
The non-publishability theorem of the proof of Goldbach’s conjecture or A story about the possibility of mathematics not being an exact science after all Dénes, Tamás – mathematician (Budapest, Hungary) email: [email protected] “Sometimes it is the people no one can imagine anything of who do the things no one can imagine.” (A. M. Turing) On the one hand, I am the protagonist of the following story, but I am also its modest chronicler. Thus, all characters in the story, as well as the documents contained in the appendices, are real. In our increasingly virtualized world, it might seem strange to read such a REAL STORY. Yet, it is important that I put it down and share it, as it represents the aristocratic reality of today’s scientific world (specifically the realm of mathematics), which we had seemed to have left behind in the second part of the 20 th century, with the golden age of a new Enlightenment upon us. We were hoping for the revival of the age of Enlightenment, when the hierarchy of feudal interests was overwritten by new ideas, by the notion of the beauty inherent to new insights. “The Theorem can be likened to a pearl, and the method of proof to an oyster. The pearl is prized for its luster and simplicity; the oyster is a complex living beast whose innards give rise to this mysteriously simple gem.” ( D.R. Hofstadter, 1945–, American mathematician, historian of mathematics) This story starts at the turn of the millennium, when in 2001 I published my Complementary Prime-Sieve theorem in the PU.M.A journal (T. -
Winter 2014 Graduate Course Descriptions
Winter 2014 Graduate Course Descriptions __________________________________________________________________ 501 AIM Student Seminar Vershynin F 12:00‐1:00pm & 3:00‐4:00pm Math 501 is a required course for all students enrolled in the Applied and Interdisciplinary Mathematics (AIM) MS and PhD graduate programs. In the Winter term, all first‐year AIM students from both programs must sign up for this course. Due to the highly specialized content of the course, enrollment is available only for students in an AIM degree program. The purpose of Math 501 is to address specific issues related to the process of studying applied mathematics in the AIM program and becoming an active member of the research community. The weekly meetings of the class will be divided among three types of sessions: 1. Focus on… “presentations.” These are presentations on various topics, some of immediate practical significance for students and others of a farther‐reaching nature. These discussions will include aspects of scholarly writing, research, and career development. 2. AIM Faculty Portraits. These are short presentations by faculty members in the Mathematics Department and other partner disciplines who are potential advisors or committee members for AIM students. The AIM faculty portraits provide a direct channel for students to discover what research is being done in various areas by current faculty, and to see what kind of preparation is required for participating in such research. 3. AIM Research Seminar Warm‐up talks. One of the course requirements for Math 501 is weekly attendance of the AIM Research Seminar that takes place from 3‐4 PM each Friday. The warm‐up talks are presentations during the regular course meeting time by particularly dynamic speakers slated to speak in the AIM Research Seminar later the same day as a way to provide background material with the goal of making the AIM Research Seminar lecture more valuable for students.