Theorem of the Day  


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Welcome to a gallery whose exhibits are the crowning achievements of mathematics: her theorems.

The first 20 terms of the Fibonacci sequence

Each day offers a different theorem (or lemma, law, formula or identity), each one worthy of adorning the walls of a mathematical Alte Pinakothek, Guggenheim, Louvre, Tate, Uffizi or Zach Feuer.

Each theorem has been presented so as to be appreciated by as wide an audience as possible. If you can have a go at a Sudoku puzzle (certainly a mathematical creature even though not an arithmetic one) then you can have a go at today's theorem.

By 'have a go' I mean admire it; turn it over in your mind; try to follow the example, if one is given; if you are studying it on-line, follow the web link, which will provide a pictorial interpretation, a proof or even a clever animation.

Click on the 'further reading' link. It will usually take you to the page for the book. O! naked commercialism — if you then buy the book I get a referral fee! I have the gravest doubts upon this subject, but I intend to crush them; it seems the neatest way to provide full bibliographic details.

Each theorem is as self-contained as possible. Whilst on-line, the Glossary icon button will take you to a Glossary page where there is a brief explanation of some parts of mathematical language; the Back arrow icon arrow will take you to a related but usually less sophisticated theorem which may shed light on today's; the Forward arrow icon arrow may point to a theorem which leads on from today's or takes you deeper into its subject. For some theorems are deeper than others; some use more technical language than others; some are just harder to understand than others.

Some days are harder than others. I hope even the most difficult days offer something of wonder.

Recent Acquisitions

A Theorem on Rectangular Tensegrities

Theorem no. 140

Coming soon...

more beautiful theorems



Day School
A Guided Tour of Theorem Country
17 October '09, Oxford University

More events

The 2009 Calendar!

Over 1000 downloads to date!

2009 Calendar "12 Theorems by Women Mathematicians"



Theorem of the Day is maintained by Robin Whitty. Comments or suggestions are welcomed by me.

All text and images and associated .pdf files © Robin Whitty, 2005–2009, except where otherwise acknowledged. See FAQ for more.