Computational Complexity Conference

CCC'21: Call for Papers

Submission Deadline: Monday, February 15, 2021, 5:00 pm PST


The conference seeks original research papers in all areas of computational complexity theory, studying the absolute and relative power of computational models under resource constraints. We welcome contributions from all topics with connections to or motivated by questions in complexity theory, broadly construed. Papers that expand the reach of complexity theory, or raise important problems that can benefit from the perspective and techniques of computational complexity, are encouraged. Possible topics include but are not limited to:

  • Complexity classes
  • Reducibility and completeness
  • Circuit complexity
  • Communication complexity
  • Algebraic complexity
  • Proof complexity
  • Complexity in other concrete computational models
  • Interactive and probabilistic proof systems
  • Logic and descriptive complexity
  • Pseudorandomness and derandomization
  • Average case complexity
  • Quantum computation
  • Parametrized complexity
  • Fine-grained complexity
  • Complexity-theoretic aspects of:
    • coding theory
    • cryptography
    • optimization (including inapproximability, continuous optimization)
    • property testing
    • streaming and sublinear computation
    • distributed computation
    • game theory
    • machine learning


Deadlines: Papers must be submitted electronically via the submission server, and received by Monday, February 15, 2021, 5:00 pm PST. Notification of acceptance will be sent by April 30, 2021, and final camera-ready copies of accepted papers will be due in mid May 2021.

Format: Submissions should start with a title page consisting of the title of the paper; each author's name, affiliation, and email address; and an abstract of 1-2 paragraphs summarizing the paper's contributions. A submission must contain within its first 10 pages a clear presentation of the merits of the paper, including discussion of its importance, prior work, and an outline of key technical ideas and methods used to achieve the main claims (similar to the content of a brief oral presentation). There is no bound on the total length of a submission, but material other than the abstract, references, and the first 10 pages is considered as supplementary and will be read at the committee's discretion.

Submissions should include proofs of all central claims.

The submission should be in single-column format, use at least 11-point font, and have standard margins and spacing between lines. Submissions deviating from these guidelines risk rejection without consideration of their merits. Instructions for formatting camera-ready versions will be communicated to the authors of accepted papers.

Additional remarks: In addition to the submission, authors may optionally send a short email to the program committee (PC) chair at containing any additional remarks for the PC, such as the relationship with independent/concurrent work, differences from prior versions, conflict of interest statements, or clarifications concerning prior reviews of the work.

Conflict of interest: We expect PC members and reviewers to recuse themselves from the evaluation of any submission, if they would not be able to give an objective opinion due to some conflict of interest (COI). Some examples why a COI may arise are being a thesis advisor, being an immediate family member or close friend, sharing a recent institutional affiliation or being a close collaborator. Any author may write to the PC chair at if there is a COI that may not be covered by the above measure. They need only give the names and affiliations of the people with whom a COI exists; no explanation is required. The COI will be held in confidence by the PC chair.

Simultaneous submission policy: Material which has been previously published in a journal or another conference proceedings, or which is scheduled for publication prior to August 2021, will not be considered for acceptance. Simultaneous submission of the same or essentially the same material to another conference with published proceedings is not allowed.

Confidentiality: All submissions will be treated as confidential, and will only be disclosed to the committee and their chosen sub-referees.


Online posting: Authors are encouraged to post full versions of their submissions in a freely accessible on-line repository such as the Electronic Colloquium on Computational Complexity or the arXiv. It is hoped that authors of accepted papers will make full versions of their papers publicly available by the camera-ready deadline.

Proceedings: The conference proceedings will be published under a Creative Commons BY license in the Leibniz International Proceedings in Informatics (LIPIcs) series. Publication in the conference proceedings does not preclude subsequent journal publication.

Presentation: Authors of accepted papers are expected to present their work at the conference. The program committee will determine time allocations for presentations (between 15 and 45 minutes).


Best student paper award: This award will be given to the best paper written solely by one or more students as judged by the program committee. A paper is eligible if all authors are full-time students on the day of the submission deadline. Authors should indicate their eligibility by using the check-box for this on the submissions page. The program committee may decline to make the award or may split it among several papers. Funding for the best student paper award is provided by EATCS.

Best paper award: This award will be given to the best paper submitted to the conference as judged by the program committee. The program committee may decline to make the award or may split it among two or more papers. Full versions of the papers chosen by the program committee to receive the best paper award will be invited for submission to the Journal of the ACM.

Special journal issue: The program committee will invite full versions of a select number of conference submissions to a special issue of the journal Theory of Computing.

Conference Information

Dates and location: The conference will be held from Tuesday, July 20 to Friday, July 23, 2021 in Toronto, ON, Canada, and will be preceded by a day of tutorials on Monday, July 19, 2021. In case public health measures related to Covid-19 make physical events infeasible, they will be held in a virtual online format. The details of the conference format will be posted in due course.

Travel allowances: In order to defray the costs of attending the conference, travel allowances will be offered to students and post-doctoral fellows. More information will be made available on the conference webpage in due time.

Visas: A visa for Canada may be needed for attending the conference, e.g., for citizens of China, India, and Russia. See the Visit Canada web page of the Government of Canada for the exact rules for visas. If a visa is needed, you may apply online or on paper; please consult the above webpage and apply as soon as possible. Feel free to contact the local arrangements committee if you need a letter to obtain your visa.

Program Committee

Local Arrangements Committee

Board of Trustees


Please contact Ashwin Nayak.

[Last modified: March 15, 2021 17:32:15]

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