acm - an acm publication
2011 Symposia

A Ubiquity symposium is an organized debate around a proposition or point of view. It is a means to explore a complex issue from multiple perspectives. An early example of a symposium on teaching computer science appeared in Communications of the ACM (December 1989).

To organize a symposium, please read our guidelines.


Ubiquity Symposium: What is Computation

Table of Contents


  1. What is Computation, Editor's Introduction, by Peter J. Denning

  2. What is Computation, Opening Statement, by Peter J. Denning

  3. The Evolution of Computation, by Peter Wegner

  4. Computation is Symbol Manipulation, by John S. Conery

  5. Computation is Process, by Dennis J. Frailey

  6. Computing and Computation, by Paul S. Rosenbloom

  7. Computation and Information, by Ruzena Bajcsy

  8. Computation and Fundamental Physics, by Dave Bacon

  9. The Enduring Legacy of the Turing Machine, by Lance Fortnow

10. Computation and Computational Thinking, by Alfred V. Aho

11. What is the Right Computational Model for Continuous Scientific Problems?, by Joseph Traub

12. Computation, Uncertainty and Risk, by Jeffrey P. Buzen

13. Natural Computation, by Erol Gelenbe

14. Biological Computation, by Melanie Mitchell

15. What is Information?: Beyond the jungle of information theories, by Paolo Rocchi

16. What Have We Said About Computation?: Closing statement, by Peter J. Denning


  • Ubiquity symposium: What have we said about computation?: closing statement

    The "computation" symposium presents the reflections of thinkers from many sectors of computing on the fundamental question in the background of everything we do as computing professionals. While many of us have too many immediate tasks to allow us time for our own deep reflection, we do appreciate when others have done this for us. Peter Freeman points out, by analogy, that as citizens of democracies we do not spend a lot of time reflecting on the question, "What is a democracy," but from time to time we find it helpful to see what philosophers and political scientists are saying about the context in which we act as citizens.

  • Ubiquity symposium: Biological Computation
    In this thirteenth piece to the Ubiquity symposium discussing What is computation? Melanie Mitchell discusses the idea that biological computation is a process that occurs in nature, not merely in ...
  • Ubiquity symposium: Natural Computation
    In this twelfth piece to the Ubiquity symposium discussing What is computation? Erol Gelenbe reviews computation in natural systems, focusing mainly on biology and citing examples of the computation that ...
  • Ubiquity symposium: Computation, Uncertainty and Risk
    In this eleventh piece to the Ubiquity symposium discussing What is computation? Jeffrey P. Buzen develops a new computational model for representing computations that arise when deterministic algorithms process workloads ...