#матлог #наука #МИАН

Дорогие коллеги,
ниже приведена информация о мероприятии "Logical Perspectives 2025:
Open Lectures", которое будет проходить 8 и 15 сентября. См. также

https://www.mathnet.ru/rus/conf2625

Обращаю ваше внимание, что доклад Александра Разборова состоится очно в МИАН (с параллельной онлайн-трансляцией).

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The Logical Perspectives event series aims at bringing together distinguished logicians to present their perspectives on the future of the field and to discuss major open problems. In particular, it includes a series of online events, called Open Lectures. The first (https://www.mathnet.ru/eng/conf1624) and second (https://www.mathnet.ru/eng/conf2202) editions of the Open Lectures were held back in 2020 and 2022. The third edition (https://www.mathnet.ru/eng/conf2625) will be held in September 2025. It will include three lectures, which are intended for a broad audience, and there will be ample time for discussion after each lecture.

In order to participate in the event, please fill in the registration form (https://forms.gle/vQL43GndBthg9bZz5).

The schedule is as follows. Note that Time is UTC+3 (Moscow).

Monday, September 8

16:00–17:15 — Alexander Razborov (University of Chicago, Steklov Mathematical Institute, https://www.mathnet.ru/eng/person8770): Propositional Proof Complexity — on-site + online

Propositional proof complexity studies efficient provability of quantifier-free statements in various proof systems and under various notions of efficiency. In this talk I will attempt to convey some of its basic concepts, ideas and results, including numerous connections to other areas in logic, theoretical computer science and beyond.

17:15–17:45 — Discussion

Monday, September 15

16:00–17:15 — Harvey Friedman (Ohio State University, https://u.osu.edu/friedman.8/): Foundational Adventures — online

I am a foundationalist. I will talk about my foundational adventures from ages 7–77, in mathematics, piano, and chess. As expected, ambitions go far beyond limited achievements. The foundations of mathematics, by far the most highly developed and successful corner of foundations (with foundations of computer science a distant second), has a great future not only in and of itself, but also as a guiding force to ignite the other comparatively backwards foundational enterprises.

17:15–17:45 — Discussion
17:45–18:00 — Break

18:00–19:15 — Walter Carnielli (State University of Campinas, https://www.cle.unicamp.br/prof/carnielli/): Negation, Denial, Falsity, Inconsistency, and Counterevidence: Some Informal and Formal Perspectives — online

While the Western tradition often treats the elusive notion of negation as secondary to affirmation, Eastern traditions regard emptiness or non-being as more fundamental. This talk examines negation, denial, consistency, inconsistency, evidence, and counterevidence through contemporary systems such as intuitionistic, paraconsistent, and modal logics, as well as logics of evidence and truth, trying to illuminate the structure of negation and its broader role in reasoning.

19:15–19:45 — Discussion

➰ ВК

10 сентября (среда) в 18:10 состоится очередное заседание теоретического семинара «Формальная философия».

Тема доклада: Frege's Philosophy of Language: On the Way to Pragmatics?

Докладчик: Рамазан Аюпов (стажер-исследователь МЛ ЛогЛинФФ)

Аннотация:
This presentation will examine the debate among Frege scholars concerning the presence of pragmatic elements in his philosophy of language. This discussion arises partly from critiques of Michael Dummett’s [1] interpretation of Frege and from the neo-Gricean debate between Laurence Horn and Christopher Potts regarding conventional implicatures and presuppositions.
Horn [2] argues that Frege anticipated Grice’s account of conventional implicatures. Frege analyzed aspects of meaning that do not affect a statement’s truth value, a concept later formalized as implicature by Grice. Horn highlights Frege’s examination of words like ‘although’, ‘but’, and ‘still’, which add layers of meaning without altering truth conditions. Frege also maintained a strict view of presuppositions (Voraussetzungen), limiting them to proper names, where failure of reference leads to truth-value gaps, making statements neither true nor false.
Thorsten Sander [3], following Horn, explores Frege’s influence on discussions of presuppositions and conventional implicatures. Sander also examines Frege’s concept of ‘side-thoughts’ (Nebengedanken) to explain linguistic phenomena seemingly incompatible with classical predicate logic. He further discusses Frege’s terms ‘colouring’ (Färbung) and ‘illumination’ (Beleuchtung) to describe the semantic contribution of words like ‘but’.
Thus, Horn and Sander affirm the presence of pragmatic elements in Frege’s work, drawing on his treatment of presuppositions, colouring, and illumination. However, scholars such as Stephen Neale, Eva Picardi, and Joan Weiner critique this pragmatic interpretation, advocating instead for a strictly semantic understanding of Frege’s philosophy, in line with Dummett.
The central question I will address is: to what extent are the arguments for the presence of pragmatics in Frege’s philosophy of language justified? On the basis of Grice’s model of pragmatics, I will argue that Frege did not develop a pragmatic theory.

[1] Dummett, M. Frege: Philosophy of Language, 2nd ed. Cambridge, MA: Harvard University Press, 1981.
[2] Horn, L. R. Toward a Fregean Pragmatics: Voraussetzung, Nebengedanke, Andeutung. In: E. Kecskes and L. Horn (eds), Explorations in Pragmatics. Berlin: de Gruyter, pages 39-69, 2007.
[3] Sander T. Frege’s Pragmatics. London: Bloomsbury Academic, 2025.
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Ждём вас в кабинете А-117 или в Zoom!

Анонс и регистрация: https://llfp.hse.ru/announcements/1081209942.html

13 сентября (суббота) в 17:00 состоится заседание научно-учебного семинара «Математическая логика и теория категорий».

Тема доклада: The consistency of Peano Arithmetic PA is provable in PA, after all.

Докладчик: Sergei Artemov, Distinguished Professor of the Graduate Center of the City University of New York.

Аннотация: We show that the famous consistency formula Con(PA) for Peano Arithmetic PA, "no x is a code of a derivation of (0=1)," is strictly stronger in PA than the statement "PA is consistent." Hence, despite the widespread belief, the unprovability of Con(PA) in PA does not yield the unprovability of consistency. Furthermore, we demonstrate that "PA is consistent" is provable in PA. These findings apply to a broad class of formal theories, including ZF set theory.

We also discuss the potential impact of these findings on the foundations of mathematics and the theory of cognition.

References:
Sergei Artemov, Consistency formula is strictly stronger in PA than PA-consistency. https://doi.org/10.48550/arXiv.2508.20346

Sergei Artemov, Serial properties, selector proofs and the provability of consistency, Journal of Logic and Computation, Volume 35, Issue 3, April 2025, exae034, https://doi.org/10.1093/logcom/exae034
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Ждём вас в кабинете А-117 или в Zoom!

Анонс и регистрация: https://llfp.hse.ru/announcements/1081272020.html

#матлог #учёба #спецсеминар

Kolmogorov seminar on complexity (for receive the zoom link, please email nikolay.vereshchagin@gmail.com)

The season will resume this monday 8 september, 18:30 MSK.

VC dimension of neural nets (Alexander Kozachinskiy)

Consider a neural network with W parameters and with sign as the activation function. How large can its VC dimension be? I will explain a folklore upper bound of O(W log W), and will give an example of Maass 1994, establishing that this bound is tight even for constant-depth neural networks.

➰ ВК

Professor David Crystal speaks on AI and the Future of Linguistics.

A once-in-a-lifetime event!
Celebrate the brilliance of
Professor David Crystal,
one of the world’s most influential linguists.
Join Sangar Najim and Sokar Sleman on 10 Sept. 2025 for an inspiring evening in the Minds in Linguistics series.

Reserve your spot today! Register now:

https://forms.gle/SRuvTxxfZpihYwSF9