Theorem of the Day



Related Places The links below will bring you (in a new window) a superb collections of sites, blogs, online magazines etc, covering large parts of mathematics. Some subjectspecific links are here.
Sources of Inspiration This site draws inspiration from: Statistical Design of the Month Pat Ballew's On This Day in Math Theorem Lists Wikipedia's List of Theorems has over 500 theorems. In addition there are long lists of Lemmas and Inequalities. Oliver Knill has a great list of theorems, currently about 250, here (1.5MB pdf, there is an arxiv version but I'm not sure how often it's updated) Noel Vaillant's Probability Tutorials can be indexed by the 140 theorems contained therein. Nathan W. Kahl has posted a list Top 100 Theorems, attributed to Paul and Jack Abad but enhanced with many wellchosen links. The site appears now to exist only as an archive but the idea has been given new life by Freek Wiedijk whose list of formalised theorems I believe to be an important and forwardlooking resource. A related effort (on an industrial scale!) is the Archive of Formal Proofs. math.stackexchange got a very rich response to "What are the most 'overpowered' theorems?" Neil Sloane's Online Encylopedia of Integer Sequences is a virtual theorem list. Not all it's >260K entries correspond to proved assertions but mostly there's at least one bona fide theorem involved somewhere! By the way, Quanta Magazine has an excellent interview with Sloane. A list of cameo appearances by theorems in the arts (thanks to Anthony Knapp for prompting this).
Mathematics Compendia & Encyclopediae Cuttheknot: Alexander Bogomolny's cornucopia of maths applets and animations. The MacTutor History of Mathematics by John J. O'Connor and Edmund F. Robertson Mathematical Atlas by Dave Rusin Mathpages by the admirable but elusive Kevin Brown Numericana is an Aladdin's cave of answers to mathematical questions, basic and advanced, maintained by Gérard P. Michon. The Numericana Hall of Fame links to some of the best web resources in mathematics (I wrote that before Dr Michon was kind enough to include theoremoftheday.org in it!). PlanetMath maintained by Nathan Egge and Aaron Krowne Springer Encyclopedia of Mathematics
Online Magazines Accromath, highquality Frenchlanguage twiceyearly Canadian school mathematics magazine AsiaPacific Mathematics Magazine, free electronic subscription gives full access. At Right Angles, A resource for School Mathematics published by Azim Premji University with Community Mathematics Centre, Rishi Valley. English language, some issues with Hindi and Kennada translation. Bulletin of the Canadian Society for the History and Philosophy of Mathematics Chalkdust, published by the students of UCL Maths Department Chance News, invaluable resource from Dartmouth College for the study of probability and statistics CMS Notes, the official newsletter of the Canadian Mathematical Society Convergence by the Mathematical Association of America (used to be Loci) James Cook Mathematical Notes from the University of Edinburgh Maths Dept Crux Mathematicorum from the Canadian Mathematical Society Primarily publishes mathematical problems but also book reviews, opinion pieces etc Eureka, the famous magazine of Cambridge's Archimedeans. Not free to read online but back issues have been archived up to 2018. European Mathematical Society Newsletter, increasingly full of excellent expository material (but increasingly big: up to 9MB pdf downloads). Fibonacci Quarterly a serious journal but with much that is accessible at all levels. Currently free online up to Volume 49 (2011) with some later special issues open access. Function by Michael Deakin, published by Monash University's mathematics department from 1977 to 2004 The Feature Column of the AMS, currently edited by David Austin, Bill Casselman, Joe Malkevitch and Tony Phillips, has an brilliant archive going back ten years, with well over 100 authoritative articles GanitCharcha Mathematics Magazine aimed at students up to K12 but with lots to entertain and inform anyone (n.b. aims to be online from issue 2). Gonit Sora, Indian (mostly Englishlanguage) magazine, with problems, interviews, book reviews etc etc Harvard College Mathematical Review serious professionallevel mathematics but much that is treated accessibly for nonprofessionals Journal of Humanistic Mathematics, serious journal but with much that is accessible to nonprofessionals Image, the magazine of the International Linear Algebra Society (individual issues download as ~6MB pdfs) Images de Mathématiques, a Frenchlanguage, magazinestyle website by Institut Henri Poincaré IMS Bulletin from the Institute of Mathematical Statistics Inference International Review of Science carries wellwritten articles on mathematics and mathematicsrelated topics. Involve serious mathematical journal but for student authorship, which implies expository variety with much that is accessible for nonprofessionals. Older issues freetoview. Bulletin of the Irish Mathematical Society, professional newsletter but with much of general interest iSquared by Sarah Shepherd, made available via the STEM Centre by MAA Kömal Hungarianlanguage magazine Loci, now Convergence, a resource form the former Mathematical Sciences Digital Library (MathDL — see also under Other Resources) London Mathematical Society Newsletter, professional newsletter but with much of general interest M500 magazine, published in support of mathematics students of the UK Open University. Free online availability (pdf format, usually between 1 and 4 MB) currently runs from 1973 to end of 2019. MAA Focus, an excellent source of expository articles, book reviews etc. From the Mathematics Association of America whose range of wonderful magazines are not otherwise online but over a hundred awardwinning articles from them are. MANIFOLD, published from 1968 to 1980 by the Mathematics Institute, University of Warwick, latterly edited and now hosted, by Ian Stewart MATEMATICALIA Spanishlanguage magazine, from 2005 to 2012 Mathematical Chronicle published by the Mathematical Chronicle Committee, 19691991: more than 20 years of top quality articles, reviews etc The Mathematics Enthusiast by the University of Montana Math Horizons, via subscription from the Mathematical Association of America but back issues are online here. Mathematics Magazine Canadian magazine for high school students Mathematical Spectrum by the Applied Probability Trust: (1968–2016) each complete issue downloadable as a pdf file (generally less than 1MB). Nautilus 'glossy' online science magazine with occasional mathematical interest Nieuw Archief voor Wiskunde Dutchlanguage magazine (some Englishlanguage articles). A selection of material is open access Opusculum, the newsletter of the Euler Society Parabola, free online magazine for highschool students by UNSW Sydney PiintheSky (issues download as ~8MB pdfs) by the Pacific Institute for the Mathematical Sciences who also have a regular newsletter available online. Plus, part of the Millenium Mathematics Project, authoritative and beautifully presented Pythagoras, Dutchlanguage magazine. Quanta by the Simons Foundation has a good mathematics section Recreational Mathematics Magazine published by the Ludus Association (most recent issue 2019) Resonance by the Indian Academy of Sciences: general science education magazine but with many interesting articles on mathematics RoseHulman Undergraduate Mathematics Journal Scholarship@Claremont is a great source of freeaccess articles. The mathematics subdiscipline index is here. SIAM News, the newsletter of the Society of Industrial and Applied Mathematics Solmu, Finnishlanguage magazine Symmetry, particle physics magazine but obviously with much of mathematical interest The Variable, magazine presented by the Saskatchewan Mathematics Teachers’ Society Vector, the journal of the British APL Association, lots of interesting mathematics with a Kenneth Iverson slant vinculum (2009–2014) again by the Saskatchewan Mathematics Teachers’ Society some issues between 2011 and 2013 not online; articles ~6MB pdf downloads
Blogs The Aperiodical – home of Carnival of Mathematics, Puzzlebomb, Travels in a Mathematical World and tons more. John Baez's Stuff – blogs, diaries, news; one of the greats! Pat Ballew's blog – a fine assortment from the author of an even more famous one. Cameron Counts – a top professional gives an unusually wideranging view of the profession. Carnival of Mathematics – showcasing mathematics blogs. Combinatorics and More – a beautiful blog by Gil Kalai. CSE Blog – fun place for puzzles, tricks, tips on quantitative methods by Pratik Poddar. Fermat's Last Theorem – the lemmas, the theorems, the conjectures, the people – FLT as a great tapestry. By Larry Freeman whose site offers several other blogs. Richard Lipton's Gödel’s Lost Letter and P=NP – insights on everything concerning the theory of computation. Tanya Khovanova's blog –"mathematics, applications of mathematics to life in general, and my life as a mathematician". Fun and sometimes funny and sometimes weird. Let's Play Math (blog carnival used to be Math Teachers at Play) Mathblogging: latest posts from hundreds of maths blogs. Math by Matt: Matt Rosenzweig's blog Edmund Harriss' blog Maxwell's Demon revolves around mathematics communication and mathematics art. A tremendous blend of images and imagination. Terence Tao's What's New – groundbreaking research and topclass expository articles... Tony's Maths Blog, aka the 1415 Puzzle in Numberland, a professional mathematician browses, muses and amuses. Top50 Computer Science Blogs – from Comtechtor; you can lose yourself for hours via this route! XOR's Hammer – a wonderful blog by Michael O'Connor, primarily about mathematical logic, but with lots and lots of other nice things
Other Resources 101 Prime Resources on Advanced Mathematics by Online Math Degrees Business Games and Lesson Plans from D’AmoreMcKim School of Business has lots of schoollevel mathematics games and exercises John D. Cook is a constant source of highquality material. Here is a sample. For Dutch speakers, Curiosa Mathematica, by Jens Bossaert, is a wonderful source of mathematical gems (currently 11.5MB). The European Mathematical Society Information Service Explained Visually from SETOSA: making mathematical concepts come alive onscreen ("interactive = intuitive; substance > information", as they put it) Gallery of public domain mathematical drawings by David Eppstein. goodcalculators.com offers a wide variety of calculation resources for everything from geometry to taxes Timothy Gowers' mathematical discussions images.math.cnrs.fr, great blogstyle collection of images and words (in French) — à ne pas manquer! The International Mathematical Olympiad Foundation: news, interviews, problem sets and, of course, the big competition! intmath, a great resource from Murray Bourne Just The Maths, a superb teaching pack for 'mathematical methods' by A.J. Hobson. The distillation of a lifetime's thinking about how it should be done. The M500 Society, one of the UK's great unsung mathematical resources, going from stength to strength after 35 years and the source of the beguiling M500 Magazine. mangahigh.com, a commercialquality computer games site for schoollevel maths. Very impressive! Math DL: now Mathcomm, the MAA's digital library. Their writing award winners, in particular, provide a wonderful collection of highlights from the different MAA publications. Math Forum, an excellent resource for schools and colleges. Math Insight, a tremendous collection of notes on mainly analysisrelated topics. MathPath: principally a summer camp for highly gifted middle school students but their math resources offer a wealth of highquality material which will appeal to any mathematician. Math Playground (used to be a blog called learninginmathland) Maths et tigues great French language site, home of the online magazine Quadrature Mudd Math Fun Facts by Francis Edward Su (does what it says – it's fun!) NRICH brings mathematics alive for school students like nowhere else. Onlinemathdegrees.org a valueable listing of undergraduate opportunities in mathematics; includes a blog with good posts such as 101 Prime Resources on Advanced Mathematics Outrageous Number Crunchers: a fun collection of links from creditreport.org for calculating everything from guitar chords to carbon footprints. Pulse Project Maths Podcast by Peter Rowlett and Samuel Hansen, conversations about whatever is current in the mathematical world. Travels in a Mathematical World: podcast site, a great source of live interviews, bits of mathematical history etc. Peter Rowlett has moved on (see above) but the site will remain, and remains a valuable visit. Virtual Maths Museum: a fine collection of images of curves, surfaces etc. Web of Stories (used to be called People's Archive) has film+transcript interviews with a galaxy of intellectual and artistic giants, including Miachael Atiyah, Freeman Dyson, Don Knuth, Benoit Mandelbrot. 
Theorem of the Day
is maintained by Robin Whitty. Comments or suggestions are welcomed by me.
"Theorem of the Day" is registered as a UK Trademark, no. 00003123351. All text and images and
associated .pdf files © Robin Whitty, 2005–2023, except where otherwise
acknowledged. See FAQ
for more.
Website terms and conditions