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# Category Archives: geometry

## Book review: Discrete and Computational Geometry

Discrete and Computational GeometrySatyan L. Devadoss & Joseph O’Rourke [Full disclosure: Princeton Press kindly sent me a free review copy of this book, and Satyan Devadoss is a (former) teacher and (current) good friend of mine. I was the TA … Continue reading

Posted in books, computation, geometry, pictures, review

## Searchable tiling database

Just a link today—check out this awesome tiling database! It’s got tons of beautiful plane tilings (with information and further reading about each one) and many ways to search through the database. It’s a great way to find examples of … Continue reading

## Book review: In Pursuit of the Traveling Salesman

As mathematical problems go, the “traveling salesman problem” (TSP) is a rare gem: it is simultaneously of great theoretical, historical, and practical interest. On the theoretical front, it is a well-known example of the class of “NP-complete” problems, which lie … Continue reading

Posted in books, computation, geometry, open problems, review
Tagged book review, salesman, TSP. traveling
6 Comments

## Dimensions: go watch! now!

I finally got around to watching the Dimensions videos, which I mentioned once before. They are super cool and will be sure to blow your mind! They start by explaining some simple tools (stereographic projection) and intuition (with references to … Continue reading

Posted in fractals, geometry, links, video
Tagged Dimensions, fibration, polytope, projection, video
2 Comments

## Book review: Viewpoints: Mathematical Perspective and Fractal Geometry in Art

This book is certainly quite different from the sort I usually read and review—but I am always interested in new and creative ways to teach mathematics! This is quite a fun book. It’s all about visual art and some of … Continue reading

## Area paradox unmasked

In my last post I presented a paradox, where a set of four pieces forming an 8×8 square could apparently be rearranged to form a 5×13 rectangle, summoning an extra unit of area out of thin air. Quite a few … Continue reading

## An area paradox

Here’s a fun paradox which has been around for quite a while and was apparently a favorite of Lewis Carroll. As you can verify for yourself, the two figures above are composed of two different rearrangements of the same four … Continue reading