"What comes first?" is critically important when computer processors perform operations that rely on each other's outputs. Leslie Lamport realized this when reading a 1975 paper by Paul Johnson and Robert Thomas proposing timestamps to track the sequence of events in a distributed algorithm.
"I immediately related that to special relativity," Einstein's theory of space-time, says Lamport, principal researcher at Microsoft Research and recipient of the 2013 ACM A.M. Turing Award. "The notion of 'at the same time' is relative. It's not an invariant notion. But what is invariant is the notion of causality." Lamport will receive the $250,000 Turing prize for his work in bringing order to the chaos of distributed computing systems that rely on communication between many autonomous computers.
No entries found
Log in to Read the Full Article
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.
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.