CCC 2023

Continuity, Computability, Constructivity

From Logic to Algorithms

Kyoto, Japan

September 25 - 29, 2023

The Workshop

CCC is a workshop series that brings together researchers applying logical methods to the development of algorithms, with a particular focus on computation with infinite data, where issues of continuity, computability and constructivity play major roles. Specific topics include exact real number computation, computable analysis, effective descriptive set theory, constructive analysis, and related areas. The overall aim is to apply logical methods in these disciplines to provide a sound foundation for obtaining exact and provably correct algorithms for computations with real numbers and other continuous data, which are of increasing importance in safety critical applications and scientific computation.

Previous workshops have been held in Cologne 2009, Trier 2012, Gregynog 2013, Ljubljana 2014, Kochel 2015, Nancy 2017, Faro 2018, Ljubljana 2019, Faro 2020 (online), Birmingham 2021 (online), and Padova 2022.

CCC 2023 is held as a RIMS symposium.
The conference is supported by JSPS KAKENHI Grant Number JP23H03346.


You can download the programme as pdf here.
All times are in Japanese Standard Time (JST).
Click here to download the abstract booklet.

Excursion and Conference Dinner

We are planning to have an informal excursion on Wednesday afternoon.
For the excursion, we meet at 14:00 in front of RIMS. For details click here.
After the excursion, we will have the conference dinner at Ganko Takasegawa Nijo-en.
We are planning to directly walk to the conference dinner venue after the excursion.
If you are planning to go to the restaurant by yourself, you can find the location here.
The dinner starts at 18:00.

Invited Speakers

Contributed Talks

  1. Bienvenu, Laurent & Delle Rose, Valentino & Steifer, Tomasz

    Almost everywhere randomness (Slides)

  2. Blanc, Manon & Bournez, Olivier

    Characterisations of polynomial-time and -space complexity classes over the reals

  3. Bournez, Olivier & Cohen, Johanne & Dardilhac, Valentin

    On the delta-decidability of decision problems for neural network questions

  4. Cioffo, Cipriano J. & Maietti, Maria E. & Maschio, Samuele

    Fibred sets within a predicative and constructive variant of Hyland's effective topos (Slides)

  5. Ciraulo, Francesco

    Kuratowski's problems in constructive Topology (Slides)

  6. Collins, Pieter & Park, Sewon & Thies, Holger

    Advances in verified set and function calculi in Coq (Slides)

  7. Gozzi, Riccardo & Bournez, Olivier

    Discontinuous IVPs with unique solutions (Slides)

  8. Hiroshima, Keita

    A number that has an elementary contractor and no elementary sum approximation

  9. Kawai, Tatsuji

    Predicative presentations of stably locally compact locales (Slides)

  10. Kihara, Takayuki

    More on the intuitionistic Borel hierarchy (Slides)

  11. Korovina, Margarita & Kudinov, Oleg

    Arithmetical complexity for archimedean order positive fields

  12. Miyabe, Kenshi

    Solovay reducibility and signed-digit representation (Slides)

  13. Müller, Norbert

    Exact Real Arithmetic and the Efficiency of Taylor Models

  14. Nakata, Satoshi

    On least realizability notions corresponding to semi-classical axioms in intuitionistic arithmetic

  15. Palombi, Daniele & Sterling, Jonathan

    Classifying topoi in synthetic guarded domain theory: The universal property of multi-clock guarded recursion

  16. Park, Sewon & Thies, Holger

    Verifying iRRAM-like implementation of exact real computation (Slides)

  17. Sabelli, Pietro

    Inductive and Coinductive predicates in the Minimalist Foundation (Slides)

  18. Sanders, Sam

    On the abyss in Kleene's computability theory (Slides)

  19. Spreen, Dieter

    The Compact Hyperspace Monad: a Constructive Approach (Slides)


The workshop invites all contributions relating to computation where issues of continuity, computability and constructivity play major roles. Specific areas of interest include:

Participation is open both in presence and online.

Extended abstracts (1-2 pages) of original work should be submitted in pdf format.

Submission link:

Deadline for Submissions August 15, 2023 (Extended) Submissions are now closed.


Registration for CCC2023 is free of charge.
Please register early, so that we can confirm the number of participants.
Deadline for registration: Sep 13
You can register at the following web page.


Room 111, Research Institute for Mathematical Sciences, Kyoto University


See also the official access information from RIMS.


Unfortunately, there are not many hotels close to Kyoto university. However, there are plenty of options in downtown Kyoto (the Shijo - Sanjo, Kawaramachi - Karasuma area). From there, you can take city bus No. 17 from Shijo Kawaramachi bus stop or from Kawaramachi Sanjo bus stop. For booking, it is recommended to use a general booking website (, expedia, etc.), but feel free to contact the local organizers if you have any specific questions.

Programme Committee

Organizing Committee