acm-header
Sign In

Communications of the ACM

News

A Satisfying Result


tiling of unequal squares, illustration

Credit: Wikimedia

A team of researchers has completed the understanding of the Keller Conjecture, first proposed in 1930, about the packing of squares, cubes, and their higher-dimensional analogues. The conjecture states that any tiling of identical hypercubes that fills space must contain a pair of neighbors that share an entire face.

You might convince yourself it is true for two or three dimensions by toying with squares or blocks. Mathematicians later established the status of the conjecture for all dimensions except seven. The new result, which shared the best paper award at the 2020 International Joint Conference on Automated Reasoning (IJCAR 2020), fills that gap. To do this, the researchers mapped more than 10,324 ways seven-dimensional hypercubes can avoid sharing any six-dimensional face onto a satisfiability problem, which asks whether some Boolean formula can ever be made true.


 

No entries found

Log in to Read the Full Article

Sign In

Sign in using your ACM Web Account username and password to access premium content if you are an ACM member, Communications subscriber or Digital Library subscriber.

Need Access?

Please select one of the options below for access to premium content and features.

Create a Web Account

If you are already an ACM member, Communications subscriber, or Digital Library subscriber, please set up a web account to access premium content on this site.

Join the ACM

Become a member to take full advantage of ACM's outstanding computing information resources, networking opportunities, and other benefits.
  

Subscribe to Communications of the ACM Magazine

Get full access to 50+ years of CACM content and receive the print version of the magazine monthly.

Purchase the Article

Non-members can purchase this article or a copy of the magazine in which it appears.
Sign In for Full Access
» Forgot Password? » Create an ACM Web Account