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Graduate course in February
by Stefania Ugolini 30 Jan '21

30 Jan '21

Università degli Studi di Milano: PhD program Stochastic quantization of the Euclidean quantum field theory Lecturer: Prof. Dr. Massimiliano Gubinelli The goal of Euclidean quantum field theory is to build probability measures on the space of distributions satisfying properties such as Euclidean invariance, reflection positivity and non-triviality, that allows to recover an interacting relativistic quantum field satisfying Wightman axioms. Stochastic quantization, first proposed by Parisi–Wu and Nelson, is a method of construction of such measures via stationary solutions of a stochastic partial differential equations driven by additive Gaussian white noise. In this course we will learn about the stochastic quantization of the Euclidean quantum field theory of a scalar boson with quartic interaction and its main properties. We introduce the Φ43 measure as the limit of the invariant measure of a finite dimensional system of stochastic differential equations. The proof proposed uses several analytic and probabilistic techniques, such as white noise analysis, weighted Besov spaces on lattice and paraproducts, which also find applications in other problems arising in the study of deterministic and stochastic singular differential equations. All these tools and ideas will be gradually introduced and explained during the lectures. The course is as much as possible self-contained and requires as a prerequisite only basic knowledge of stochastic and functional analysis. Scheduling: February 15, 16, 18, 22, 25 from 10:00 to 12:00 and from 14:00 to 16:00 Online via Zoom (see the following link) Course page: https://www.iam.uni-bonn.de/abteilung-gubinelli/sq-lectures-milan-ws2021 <signaturebeforequotedtext></signaturebeforequotedtext><signatureafterquotedtext></signatureafterquotedtext>

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Seminario Antonio Agresti RM1
by Nappo, Giovanna 29 Jan '21

29 Jan '21

SEMINARIO DI PROBABILITA' E STATISTICA MATEMATICA Dipartimento di Matematica "Guido Castelnuovo" Lunedì 08 febbraio 2021 Ore 16:00 (modalità telematica con Zoom) Antonio AGRESTI (Dottorato in Matematica, Sapienza Università di Roma) Nonlinear parabolic stochastic evolution equations in critical spaces. Abstract: Critical spaces for non-linear equations are important due to scaling invariance, and in particular this plays a central role in fluid dynamics. In this talk we introduce and discuss local/global well-posedness, and blow-up criteria for stochastic parabolic evolution equations in critical spaces. Our results extend the celebrated theory of Prüss, Wilke and Simonett for deterministic PDEs. Due to the presence of noise it is unclear that a stochastic version of the theory is possible, but as we will show a suitable variation of the theory remains valid. We will also explain several features which are new in both the deterministic and stochastic framework. In particular, we discuss a new bootstrap method to prove regularization of solutions to (S)PDEs, which can also be applied in critical situations. Our theory is applicable to a large class of semilinear and quasilinear parabolic problems which includes many of the classical SPDE. During the talk we give applications to stochastic reaction-diffusion equations and stochastic Navier-Stokes equations with gradient noise. This is a joint work with Mark Veraar (TU Delft). Link Zoom https://uniroma1.zoom.us/j/81656265460?pwd=UmlZQzBDY2VmSUwrNitZbkNWMERIdz09

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MSP 2021
by Pietro Rigo 29 Jan '21

29 Jan '21

We are pleased to announce the second edition of the Workshop on The Mathematics of Subjective Probability (MSP 2021) that will take place at the University of Milano-Bicocca on September 1-3, 2021. As in the preceding edition, this workshop is intended as a forum for scholars of different fields who are interested in modeling probability as part of the behaviour of individuals rather than on a purely axiomatic basis. Papers on Probability Theory are obviously welcome as well as papers from Economic Theory, Game Theory, Statistics and Mathematics. We intend to hold the conference in the classical form, with speakers attending physically although, as of now, we cannot exclude that at least in part it will have to take place remotely The following speakers have accepted our invitation to deliver a talk: * Nabil Al-Najjar, Northwestern University; * Pierpaolo Battigalli, Università Bocconi; * K.P.S. Bhaskara-Rao, Indiana University Northwest; * Giulianella Coletti, Università di Perugia; * Massimo Marinacci, Università Bocconi; * Frank Riedel, University of Bielefeld. We invite all interested researchers to submit their papers for presentation. Papers should be submitted electronically via e-mail at the address MSP2021(a)unimib.it<mailto:MSP2021@unimib.it> . Submission will be possible until July 1st; notification of acceptance will be received by july 15th. For all details concerning the conference, please refer to the website msp2021.campus.unimib.it<https://www.msp2021.campus.unimib.it/>. Gianluca Cassese, Pietro Rigo, Barbara Vantaggi

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Seminar announcement
by Marco Scarsini 29 Jan '21

29 Jan '21

*Thursday, 4 February, 17:00 CET* *Annie Liang**, *Northwestern University Dynamically Aggregating Diverse Information <http://mailsender.luiss.it/lists/lt.php?id=cRpQAAYCSAUGBgBOVgFdBQs> Discussants: Jacopo Perego and Weijie Zhong The paper can be found here <https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3385451>. This is the link to the Virtual Room <http://mailsender.luiss.it/lists/lt.php?id=cRpQAAYBSAUGBgBOVgFdBQs>. The schedule of the upcoming seminars can be found here <https://economiaefinanza.luiss.it/en/seminari/prossimi-seminari>. If you want to receive announcements of future seminars, please fill out this form <https://docs.google.com/forms/d/e/1FAIpQLSeDxM-M5ogG43elgjC-lNCp0BDhISiZHG0…> . ******************************************************* Marco Scarsini Dipartimento di Economia e Finanza Luiss Viale Romania 32 00197 Roma, ITALY URL: http://docenti.luiss.it/scarsini/

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Fwd: [owps] One World Probability Seminar Thursday January 28, 2021
by Faggionato, Alessandra 28 Jan '21

28 Jan '21

inoltro per problemi tecnici grazie alessandra ---------- Forwarded message --------- Da: One World Probability <ow.probability(a)gmail.com> Date: gio 28 gen 2021 alle ore 15:03 Subject: Re: [owps] One World Probability Seminar Thursday January 28, 2021 To: <owps(a)lists.bath.ac.uk> Dear All, If you have trouble joining the meeting using the zoom link below, please try using the link on the website. We apologise for any problems. Amanda and Alessandra On Wed, Jan 27, 2021 at 8:26 AM One World Probability < ow.probability(a)gmail.com> wrote: > Tomorrow's speakers in the One World Probability Seminar are > (Note: all times are in UTC. *Due to time changes, you should check what > that translates to in your location*) > ------------------------------------------------ > > (14:00-15:00 UTC) Speaker: Cristina Toninelli (Université Paris Dauphine) > Title: Universality results for interacting particle systems with > dynamical constraints > Abstract: We introduce the kinetically constrained models (KCM), a class > of interacting particle systems with a simple spin flip dynamics subject to > local dynamical constraints. Each vertex is resampled (independently) at > rate one by tossing a (1-q)-coin iff a certain neighbourhood of the vertex > contains no particles. In other words, the holes (empty vertices) act as > facilitating sites. When q shrinks to 0, the presence of the constraints > gives rise to glassy dynamics, in particular to an anomalous divergence of > the characteristic time scales. Thus, KCM are extensively used in physics > literature to model the liquid-glass transition, a longstanding open > problem in condensed matter physics. > > We focus on the behavior of E(T_0), the mean over the stationary process > of the first time at which the origin becomes empty. Our results establish > the universality classes of KCM in two dimensions: we group all possible > constraints into distinct classes with all models in a class featuring the > same divergence for E(T_0) as q->0. Within each class, we present an > efficient relaxation mechanism that involves the cooperative motion of > large rare patches of empty sites and we use it to determine matching upper > and lower bounds for E(T_0). > > Joint work with L.Marêché, I.Hartarsky, F.Martinelli and R.Morris > > (15:00-16:00 UTC) Fabio Martinelli (Università Roma Tre) > Title: Sharp threshold for the FA-2f kinetically constrained model > Abstract: > The Fredrickson-Andersen 2-spin facilitated model (FA-2f) on the > d-dimensional lattice, d ≥ 2, is a paradigmatic interacting particle system > with kinetic constraints (KCM) featuring "dynamical facilitation", an > important mechanism in condensed matter physics. In FA-2f a site may change > its state only if at least two of its nearest neighbors are empty. The > process, while reversible w.r.t. a product Bernoulli measure, has > degenerate jumps rates and it is non-attractive, with an anomalous > divergence of characteristic time scales as the density q of the empty > sites tends to zero. A natural random variable encoding the above features > is the first time T at which the origin becomes empty for the stationary > process. Our main result is the sharp threshold T ≍ Exp[ d > λ(d,2)/q^(1/(d-1)) ] w.h.p. as q → 0, with λ(d,2) the threshold constant > for the 2-neighbor bootstrap percolation, the monotone deterministic > cellular automaton counterpart of FA-2f. This is the first sharp result for > a critical KCM. Besides settling various controversies accumulated in the > physics literature over the last four decades, our novel techniques enable > completing the recent ambitious program on the universality phenomenon for > critical KCM and establishing sharp thresholds for other two-dimensional > KCM. > > Joint work with I. Hartarski and C. Toninelli > > ------------------------------------------------ > > The zoom link will appear the day before on the OWPS website: > https://www.owprobability.org/one-world-probability-seminar > <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.owpro…> > > It can also be directly accessed through the link below: > https://uniroma1.zoom.us/j/83154591101?pwd=dkZyekxwa1Z1b2w2bW5SOWY3L21Xdz09 > <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Funiroma1.…> > > Please feel free to circulate this email. > > We hope to see you all tomorrow! > One World Probability Team > -- ************************************************* Prof. Alessandra Faggionato http://www1.mat.uniroma1.it/~faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 5, Phone (0039) 06 49913252 *************************************************

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ABC in Svalbard, 12-13 April, 2021 - Mirror in Grenoble
by Julyan Arbel 27 Jan '21

27 Jan '21

Dear all, The approximate Bayesian computation (ABC) conference is planned to be held in Svalbard on 12-13 April, 2021, in a hybrid way: on top to the on-site meeting, there will be two physical mirrors (one in Brisbane and one in Grenoble), and all talks will be live-streamed. If you wish to participate to the virtual event, stay tuned for further information on: https://sites.google.com/view/abcinsvalbard/home If you consider participating to Grenoble mirror (free of charge), please fill the form here: https://sites.google.com/view/abcinsvalbard-grenoble-mirror/ in order to receive further notice about the organisation. Best, Julyan Arbel and Christian Robert

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Padova Online Seminar by Michele Salvi (Università di Roma Tor Vergata) [Friday, Feb. 05 at 14.30]
by alessandra bianchi 27 Jan '21

27 Jan '21

Dear Colleagues, We would like to invite you to the following Probability seminar that will take place on February 05 at 14.30 by the zoom platform. ________________________________________________________ Speaker: Michele Salvi (Università di Roma Tor Vergata) Title: Scale-free percolation in continuous space 05 FEBRUARY (Friday) - 14:30 zoom link: TBA (available on the webpage https://www.math.unipd.it/~bianchi/seminari/ ) Abstract: The scale-free percolation random graph features three fundamental properties that are often present in large real-world structures (social networks, communication networks, inter-banking systems and so on), but which are never present at once in classical models: (1) Scale-free: the degree of the nodes follows a power law; (2) Small-world: two nodes are typically at a very small graph distance; (3) Positive clustering coefficient: two nodes with a common neighbour have a good chance to be linked. We study a continuous version of scale-free percolation and its possible application to the statistical analysis of a dataset provided by the French Ministry of Agriculture. We discuss some stochastic processes (random walks and particle systems) on these kinds of structures with the final goal of understanding how an epidemic would spread. -- Alessandra Bianchi Dip. di Matematica Università di Padova Via Trieste, 63 - 35121 Padova, Italy phone: +39 049 827 14 06 fax: +39 049 827 14 28 e-mail: bianchi(a)math.unipd.it http://www.math.unipd.it/~bianchi/

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Fwd: [owps] One World Probability Seminar Thursday January 28, 2021
by Faggionato, Alessandra 27 Jan '21

27 Jan '21

Buongiorno, vi inoltro l'annuncio del OWPS di domani. Saluti Alessandra ---------- Forwarded message --------- Da: One World Probability <ow.probability(a)gmail.com> Date: mer 27 gen 2021 alle ore 09:28 Subject: [owps] One World Probability Seminar Thursday January 28, 2021 To: <owps(a)lists.bath.ac.uk> Tomorrow's speakers in the One World Probability Seminar are (Note: all times are in UTC. *Due to time changes, you should check what that translates to in your location*) ------------------------------------------------ (14:00-15:00 UTC) Speaker: Cristina Toninelli (Université Paris Dauphine) Title: Universality results for interacting particle systems with dynamical constraints Abstract: We introduce the kinetically constrained models (KCM), a class of interacting particle systems with a simple spin flip dynamics subject to local dynamical constraints. Each vertex is resampled (independently) at rate one by tossing a (1-q)-coin iff a certain neighbourhood of the vertex contains no particles. In other words, the holes (empty vertices) act as facilitating sites. When q shrinks to 0, the presence of the constraints gives rise to glassy dynamics, in particular to an anomalous divergence of the characteristic time scales. Thus, KCM are extensively used in physics literature to model the liquid-glass transition, a longstanding open problem in condensed matter physics. We focus on the behavior of E(T_0), the mean over the stationary process of the first time at which the origin becomes empty. Our results establish the universality classes of KCM in two dimensions: we group all possible constraints into distinct classes with all models in a class featuring the same divergence for E(T_0) as q->0. Within each class, we present an efficient relaxation mechanism that involves the cooperative motion of large rare patches of empty sites and we use it to determine matching upper and lower bounds for E(T_0). Joint work with L.Marêché, I.Hartarsky, F.Martinelli and R.Morris (15:00-16:00 UTC) Fabio Martinelli (Università Roma Tre) Title: Sharp threshold for the FA-2f kinetically constrained model Abstract: The Fredrickson-Andersen 2-spin facilitated model (FA-2f) on the d-dimensional lattice, d ≥ 2, is a paradigmatic interacting particle system with kinetic constraints (KCM) featuring "dynamical facilitation", an important mechanism in condensed matter physics. In FA-2f a site may change its state only if at least two of its nearest neighbors are empty. The process, while reversible w.r.t. a product Bernoulli measure, has degenerate jumps rates and it is non-attractive, with an anomalous divergence of characteristic time scales as the density q of the empty sites tends to zero. A natural random variable encoding the above features is the first time T at which the origin becomes empty for the stationary process. Our main result is the sharp threshold T ≍ Exp[ d λ(d,2)/q^(1/(d-1)) ] w.h.p. as q → 0, with λ(d,2) the threshold constant for the 2-neighbor bootstrap percolation, the monotone deterministic cellular automaton counterpart of FA-2f. This is the first sharp result for a critical KCM. Besides settling various controversies accumulated in the physics literature over the last four decades, our novel techniques enable completing the recent ambitious program on the universality phenomenon for critical KCM and establishing sharp thresholds for other two-dimensional KCM. Joint work with I. Hartarski and C. Toninelli ------------------------------------------------ The zoom link will appear the day before on the OWPS website: https://www.owprobability.org/one-world-probability-seminar <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.owpro…> It can also be directly accessed through the link below: https://uniroma1.zoom.us/j/83154591101?pwd=dkZyekxwa1Z1b2w2bW5SOWY3L21Xdz09 <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Funiroma1.…> Please feel free to circulate this email. We hope to see you all tomorrow! One World Probability Team -- ************************************************* Prof. Alessandra Faggionato http://www1.mat.uniroma1.it/~faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 5, Phone (0039) 06 49913252 *************************************************

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Seminario Prisma
by Domenico Marinucci 26 Jan '21

26 Jan '21

Cari colleghi Lunedì prossimo avrà inizio il ciclo mensile di seminari online promosso dal Gruppo UMI PRISMA: 1 Febbraio 2021, ore 16:00-18:00: Franco Flandoli, Mario Maurelli TITLE: Regularization by noise ABSTRACT: The presence of the irregular fluctuations of a noise sometimes improves the theory of differential equations, ordinary or partial, a phenomenon today called "regularization by noise". This joint talk will introduce the problem in finite dimensions, by some classical and some more recent examples and results. Then it moves to SPDEs, where the results are mostly recent and under investigation. The different roles of additive noise and multiplicative transport type noise, the latter with its fluid mechanic flavour, will be described. Collegamento Teams: https://teams.microsoft.com/l/meetup-join/19%3a667d2414be564c5d8fba30acffeb… Grazie per l'attenzione e scusate le ripetizioni, Domenico Marinucci e Claudia Ceci -- @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Domenico Marinucci Dipartimento di Matematica Università di Roma Tor Vergata https://www.mat.uniroma2.it/~marinucc/ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

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Annuncio seminario - 28 gennaio ore 14:00 - Alessio Farcomeni
by Anna Paganoni 25 Jan '21

25 Jan '21

Buongiorno, ricordo il seguente Seminario MOX on-line di giovedì organizzato dal gruppo Stat@MOX. 28.1, ore 14:00 Link: https://mox.polimi.it/elenco-seminari/?id_evento=2001&t=763721 Speaker: Alessio Farcomeni, Università Roma Tor Vergata Titolo: Nowcasting the Italian epidemic outbreak of SARS-CoV-2 Abstract: In the talk, we briefly discuss the main epidemiological features of SARS-CoV-2 one year into the pandemic, giving also a short account of the public data available for Italy and of the main limits of lay analyses. We then discuss an accurate method for short-term forecasting ICU occupancy at local level. Our approach is based on an optimal ensemble of two simple methods: a generalized linear mixed regression model which pools information over different areas, and an area-specific non-stationary integer autoregressive methodology. Optimal weights are estimated using a leave-last-out rationale. Daily predictions between February 24th and November, 27th 2020 have a median error of 3 beds (third quartile: 8) at regional level, with coverage of 99% prediction intervals that exceeds the nominal one. Finally we present a different method based on a modified non-linear GLM for each indicator, including the potential effect of exogenous variables, based on appropriate distributional assumptions and a logistic-type growth curve. This allows us to accurately predict important characteristics of the epidemic (e.g., peak time and height). Based on joint works with Pierfrancesco Alaimo di Loro, Fabio Divino, Giovanna Jona Lasinio, Gianfranco Lovison, Antonello Maruotti, Marco Mingione Contatto: francesca.ieva(a)polimi.it Buona giornata Anna Maria Paganoni -- Anna Maria Paganoni MOX - Modeling and Scientific Computing Dipartimento di Matematica "F. Brioschi" Politecnico di Milano Piazza Leonardo da Vinci, 32 I-20133 Milano - Italy tel. +39 02 2399 4574 fax. +39 02 2399 4568 e.mail: anna.paganoni(a)polimi.it

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