Thu 01 May 15:00: An Explicit Filtered Lie Splitting Scheme for the Original Zakharov System with Low Regularity Error Estimates in All Dimensions
In this talk, we present low-regularity numerical schemes for nonlinear dispersive equations, with a particular focus on the Zakharov system (ZS) and the “good” Boussinesq (GB) equation. These models exhibit strong nonlinear interactions and are known to pose significant analytical and numerical challenges when the solution has limited regularity.
We concentrate on our recent results for the Zakharov system, where we construct and analyze an explicit filtered Lie splitting scheme applied directly to its original coupled form. This method successfully overcomes the essential difficulty of derivative loss in the nonlinear terms, which not only obstructs low-regularity analysis, but has long prevented rigorous error estimates for explicit Lie splitting schemes based directly on the original Zakharov system. By developing multilinear estimates in discrete Bourgain spaces, we rigorously prove the first explicit low-regularity error estimate for the original Zakharov system, and also the first such result for a coupled system within the Bourgain framework. The analytical strategy developed here can also be extended to other dispersive equations with derivative loss, offering a way to overcome both low-regularity difficulties and the fundamental obstacle posed by derivative-loss nonlinearities. Numerical experiments confirm the theoretical predictions.
- Speaker: Hang Li (Sorbonne Université)
- Thursday 01 May 2025, 15:00-16:00
- Venue: Centre for Mathematical Sciences, MR14.
- Series: Applied and Computational Analysis; organiser: Georg Maierhofer.
Tue 06 May 14:00: The Porous Medium Equation: Multiscale Analysis of a Zero-Range Process, Integrability Estimate and Large Deviations
We consider a doubly-rescaled zero-range process with jump rate $g(k)=k\alpha, \alpha>1$, with scaling parameters $\chi_N\to 0, N\to \infty$, as a microscopic model for the porous medium equation. As a result of the superlinear jump rate, new ingredients are needed in addition to the Kipnis-Landim framework, of which the most interesting is an integrability estimate: Even if one can prove rapid equilibration on macroscopically small boxes, the superexponential estimate could fail due to configurations in which a vanishing proportion of mass produces a nonvanishing contribution to the $L\alpha_{t,x}$ norm. In order to rule this out, we show that the realisations of the particle system enjoy pathwise regularity estimates with superexponentially high probability across suitably chosen scales, which can be used in a multiscale argument to obtain the necessary integrability. Joint work with Benjamin Gess (TU Berlin / Max-Planck Institute for Mathematics in the Sciences)
- Speaker: Daniel Heydecker (Imperial College)
- Tuesday 06 May 2025, 14:00-15:00
- Venue: MR12.
- Series: Probability; organiser: Perla Sousi.
Tue 13 May 16:00: Title to be confirmed
Abstract not available
- Speaker: Longfei Shangguan, University of Pittsburgh
- Tuesday 13 May 2025, 16:00-17:00
- Venue: Computer Lab, FW26 and Online.
- Series: Mobile and Wearable Health Seminar Series; organiser: Cecilia Mascolo.
Thu 05 Jun 14:00: Materials RIG Seminar: Professor Sally Brooker
tbc
- Speaker: Prof. Sally Brooker, University of Otago
- Thursday 05 June 2025, 14:00-15:00
- Venue: Dept. of Chemistry, Unilever Lecture Theatre.
- Series: Materials Chemistry Research Interest Group; organiser: Sharon Connor.
Thu 05 Jun 14:00: Materials RIG Seminar: Professor Sally Brooker
tbc
- Speaker: Prof. Sally Brooker, University of Otago
- Thursday 05 June 2025, 14:00-15:00
- Venue: Dept. of Chemistry, Unilever Lecture Theatre.
- Series: Materials Chemistry Research Interest Group; organiser: Sharon Connor.
Optimization of crystallization dynamics in wide-bandgap bromine–iodine perovskite films for high-performance perovskite–organic tandem solar cells
DOI: 10.1039/D5EE00264H, PaperZonglong Song, Jiangfeng Wang, Yuqi Bao, Jie Zeng, Deng Wang, Jiang He, Peide Zhu, Bo Jiang, Zhixin Liu, Siru He, Yanna Hou, Ziyang Hu, Chen Xie, Yongsheng Chen, Yongsheng Liu, Xingzhu Wang, Baomin Xu
By introducing moroxydine hydrochloride to optimize the crystallization of wide-bandgap perovskites, phase separation of halides was suppressed, achieving a PCE of 18.76%. This technology significantly improved photothermal stability.
To cite this article before page numbers are assigned, use the DOI form of citation above.
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Fri 06 Jun 16:00: TBA
Abstract not available
- Speaker: Kay Schönwald (Zurich U.)
- Friday 06 June 2025, 16:00-17:00
- Venue: MR19 (Potter Room, Pavilion B), CMS.
- Series: HEP phenomenology joint Cavendish-DAMTP seminar; organiser: Terry Generet.
Machine learning-assisted benign transformation of three zinc states in zinc ion batteries
DOI: 10.1039/D5EE00650C, Paper Open Access   This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.Jianbo Dong, Guolang Zhou, Wenhao Ding, Jiayi Ji, Qing Wang, Tianshi Wang, Lili Zhang, Xiuyang Zou, Jingzhou Yin, Edison Huixiang Ang
A machine-learning-designed cerium-iron MOF layer enhances Zn anode stability, achieving over 4300 hours at 1 mA cm−2 and 99.8% coulombic efficiency over 1400 cycles at 2 mA cm−2, providing a cost-effective protective strategy.
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Wed 17 Sep 11:00: LMB Seminar - Title TBC
Abstract not available
- Speaker: Nenad Ban - ETH Zurich
- Wednesday 17 September 2025, 11:00-12:00
- Venue: In person in the Max Perutz Lecture Theatre (CB2 0QH) and via Zoom link https://mrc-lmb-cam-ac-uk.zoom.us/j/97937314535?pwd=SciQzQiuFkLGF3ERwcMiLLTEbryUxV.1.
- Series: MRC LMB Seminar Series; organiser: Scientific Meetings Co-ordinator.
Fri 13 Jun 16:00: Thermal vortex rings: the vortex dynamics
A thermal is a convective structure generated from a localized buoyancy anomaly, say, released from the surface. Since it evolves into a donuts-shaped vorticity, the vortex ring, it may be more precisely called the thermal vortex ring. Thermals are often considered basic elements of fully-developed convection in astrophysical and geophysical flows, as most vividly visualized by a cauliflower-like structure of cumulus-convective clouds. This talk revisits the problem of the thermal vortex ring from a point of view of the vortex dynamics. More specifically, I present: 1) a modon solution of a thermal vortex ring as an extension of Hill’s vortex; 2) a concise description based on the volume integrals of the vorticity weighted by a power of the distance from the vortex-ring axis; 3) derivation of a classical similarity solution based on it, as well as 4) a development of a closed system based on an explicit simulation. Those investigations as a whole suggest that the thermal vortex ring could be interpreted as a type of two-dimensional turbulence.
- Speaker: Dr Jun-Ichi Yano, University of Reading
- Friday 13 June 2025, 16:00-17:00
- Venue: MR2.
- Series: Fluid Mechanics (DAMTP); organiser: Professor Grae Worster.
Fri 30 May 16:00: Perfect modelling of linear and nonlinear vibration
It is suggested that a universal, simple equation exists that can be used for modelling all linear and nonlinear vibration. The motivation for this work comes from vibration testing. Here, a structure may be set into vibration and the resulting motion captured. This motion can be modelled perfectly by the proposed equation. More surprisingly the model will be familiar to all those who know about vibration. Finally, a good algorithm exists for fitting the model to data. The fitted equation is the homogeneous solution of the differential equation describing the structure and consequently the differential equation, linear or nonlinear, can be deduced. All these claims seem too good to be true! The talk will give details of the equation the modelling algorithm and applications. The author is interested your view of the universality of the modelling.
- Speaker: Dr Hugh Goyder, Cranfield/ AWE
- Friday 30 May 2025, 16:00-17:00
- Venue: JDB Seminar Room, CUED.
- Series: Engineering - Dynamics and Vibration Tea Time Talks; organiser: div-c.
Tue 29 Apr 15:15: BSU Seminar: "Investigating complex dependence structures using Bayesian mixture modelling" This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/meeting/register...
We investigate complex dependence structures between categorical variables. We utilise Bayesian partitioning on subjects and variables simultaneously, referring to clusters of variables as views. We incorporate a variable selection procedure that highlights the variables that drive the clustering of the subjects within each view. We derive theoretical results on the relation between the variables’ dependence structure and the inferences derived from the implemented clustering. We demonstrate how such clustering results can be used to assist loglinear graphical model determination with simulated and real data sets.
This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/meeting/register/7PLSTFN7QM6iUvdzQaegEw
- Speaker: Dr Michail Papathomas, University of St Andrews
- Tuesday 29 April 2025, 15:15-16:15
- Venue: Large Seminar Room, East Forvie Building, Forvie Site Robinson Way Cambridge CB2 0SR..
- Series: MRC Biostatistics Unit Seminars; organiser: Alison Quenault.
Fri 13 Jun 15:30: Science advice under uncertainty
In this session, Amy Orben, the leader of the Digital Mental Health Group at the MRC Cognition and Brain Sciences Unit, will talk about her experience of having to support evidence-based policy in the area of teen mental health and social media. Her vision on how this could be improved was described in Orben, Amy, and J. Nathan Matias, ‘Fixing the science of digital technology harms’, Science 388, no. 6743 (2025): 152–155.
- Speaker: Amy Orben (MRC Cognition and Brain Sciences Unit)
- Friday 13 June 2025, 15:30-17:00
- Venue: Seminar Room 2, Department of History and Philosophy of Science.
- Series: Coffee with Scientists; organiser: Marta Halina.
Fri 16 May 14:00: Title to be confirmed
Abstract not available
- Speaker: Professor Dan V Nicolau, McGill University
- Friday 16 May 2025, 14:00-15:00
- Venue: Oatley 1 Meeting Room, Department of Engineering.
- Series: Engineering - Mechanics and Materials Seminar Series; organiser: div-c.
Fri 30 May 15:30: The Culture Lab
Abstract not available
- Speaker: Helene Scott-Fordsmand (Clare Hall & HPS, Cambridge) and Anatolii Kozlov (Science & Technology Studies, UCL)
- Friday 30 May 2025, 15:30-17:00
- Venue: Seminar Room 2, Department of History and Philosophy of Science.
- Series: Coffee with Scientists; organiser: Marta Halina.
One-Stone-Two-Birds: Over 26% Efficiency in Perovskite Solar Cells via Synergistic Crystallization & Interface Regulation
DOI: 10.1039/D5EE00189G, PaperBoxin Jiao, Liguo Tan, Yiran Ye, Ningyu Ren, Minghao Li, Hang Li, Xiaoyi Li, Chenyi Yi
Organic-inorganic hybrid perovskites have emerged as promising photovoltaic materials due to their excellent photoelectronic properties and low-cost fabrication techniques. However, the performance and stability of perovskite solar cells (PSCs) are...
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Tue 29 Apr 14:00: BSU Seminar: "Common atoms mixture models in some biostatistical inference problems" This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/meeting/register...
We consider several examples of statistical inference for two or more related populations. In one example we characterize two patient populations that are relevant in the construction of a clinical study design, and propose a method to adjust for detected differences. Another example is about comparative immune profiling under two biologic conditions of interest when we identify shared versus condition-specific homogeneous cell subpopulations. In a third example we model spatially aligned cell subpopulations for spatial transcriptomics data.
Bayesian inference in all three applications requires prior probability models for two or more related distributions. We build on extensive literature on such models based on Dirichlet process priors. Related models are commonly known as dependent Dirichlet processes (DDP), with many variations and extensions beyond the Dirichlet process model.
One special feature in all three motivating applications is the focus on understanding the nature of the dependence across the related populations. In one application we aim to adjust for differences in population heterogeneity, in another we aim to identify and understand homogeneous subpopulations that are characteristic for one or the other condition.
This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/meeting/register/4uUskN5ZQjaJzckpMbxQ1Q
- Speaker: Prof Peter Mueller, University of Texas
- Tuesday 29 April 2025, 14:00-15:00
- Venue: Large Seminar Room, East Forvie Building, Forvie Site Robinson Way Cambridge CB2 0SR..
- Series: MRC Biostatistics Unit Seminars; organiser: Alison Quenault.
Thu 08 May 11:30: TBC
Abstract not available
- Speaker: Emma Lepinay, IEEF
- Thursday 08 May 2025, 11:30-12:30
- Venue: Open Plan Area, Institute for Energy and Environmental Flows, Madingley Rise CB3 0EZ.
- Series: Institute for Energy and Environmental Flows (IEEF); organiser: Catherine Pearson.
Thu 01 May 11:30: Interaction of Mechanical Ventilation and Natural Convection
Abstract not available
- Speaker: Dan Toy, IEEF
- Thursday 01 May 2025, 11:30-12:30
- Venue: Open Plan Area, Institute for Energy and Environmental Flows, Madingley Rise CB3 0EZ.
- Series: Institute for Energy and Environmental Flows (IEEF); organiser: Catherine Pearson.
Tue 13 May 11:00: Single charge pion production cross-sections at MicroBooNE
Single charge pion production cross-sections at MicroBooNE
- Speaker: Philip Detje: Cavendish Laboratory, University of Cambridge
- Tuesday 13 May 2025, 11:00-12:00
- Venue: Seminar Room -- RDC D2.002 .
- Series: Cavendish HEP Seminars; organiser: Dr Paul Swallow.