The random timestep Euler method and its continuous dynamics
Abstract. Ordinary differential equation (ODE) solvers with randomly sampled timestep sizes appear in the context of chaotic dynamical systems, differentia
When randomising the timestep sizes in Eulerβs method, we need to linearly interpolate between subsequent timepoints to approximate the ODE solution at times of interest. The resulting piecewise linear path can sometimes be written as a Markov process.
I have analysed this Markov process:
27.11.2025 21:16
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Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences: Vol 383, No 2298
Andrea Bertozzi, Nadia Drenska, Matt Thorpe, and I have guest edited a theme issue on βPartial differential equations in data scienceβ in the Philosophical Transactions of the Royal Society A.
Take a look: royalsocietypublishing.org/toc/rsta/202...
@royalsociety.org @royalsocietypublishing.org
05.06.2025 21:46
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#Oberwolfach: every mathematicianβs happy place
25.04.2025 07:48
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Exciting news! π
Best of luck for the election, Master!
25.04.2025 07:47
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A few years ago, BjΓΆrn Sprungk and I had written a contribution towards the βSnapshots of Modern Mathematics from #Oberwolfachβ (publications.mfo.de/handle/mfo/3...).
Once in a while a collection of snapshots is published in a volume. I have received my copy today. π
06.04.2025 10:55
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Why do people call it _adaptive MCMC_ instead of
- CMC
- βMβCMC
- \hat{M}CMC
- MπCMC
19.03.2025 09:36
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#sciencememe
20.02.2025 20:22
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2nd RSS/Turing Workshop on Gradient Flows for Sampling, Inference, and Learning
Please find below the announcement for the
2nd RSS/Turing Workshop on Gradient Flows for Sampling, Inference, and Learning
(I am a speaker βΊοΈ)
07.02.2025 12:50
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Earlier today I gave my first talk for 2025 β in the Applied Mathematics Seminar at the University of Glasgow! Great audience and nice discussions afterwards. π
30.01.2025 18:24
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Luxair plane at an airport
Did you know that Schengen is a small village in Luxembourg? It is right at the French-German-Luxembourgish trijunction. I grew up nearby and I can assure you that it is my favourite border to cross.
See you in 2025! βΊοΈ
19.12.2024 10:42
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Deep Gaussian Process Priors for Bayesian Image Reconstruction
In image reconstruction, an accurate quantification of uncertainty is of great importance for informed decision making. Here, the Bayesian approach to inverse problems can be used: the image is repres...
Stationary Gaussian processes are often inappropriate as priors in Bayesian image reconstruction. When using non-stationary priors, the non-stationarity needs to be carefully estimated.
New preprint (with Aretha L. Teckentrup and Simon Urbainczyk)
arxiv.org/abs/2412.10248
16.12.2024 06:28
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Overleaf is down. What was the last thing you were writing about on there?
Iβll start: the K-Means method
03.12.2024 13:09
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Thank you for the nice feedback! π
02.12.2024 22:53
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Mathematics Showdown 2023 - YouTube
Contributions to the Mathematics Showdown 2023 at the Edinburgh Science Festival.
At last yearβs Edinburgh Science Festival, we organised a βMathematics Showdownβ: five PhD students give engaging research talks for a general audience, the audience votes for a winner.
Here are the talks:
02.12.2024 07:39
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Markovian #Meme.
29.11.2024 07:05
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Image segmentation in radioastronomy with physical models on graphs at The University of Manchester on FindAPhD.com
PhD Project - Image segmentation in radioastronomy with physical models on graphs at The University of Manchester, listed on FindAPhD.com
Open PhD position
Anna Scaife and I are looking for a PhD student interested in analysing astronomical images using modern physics-on-graphs-based machine learning methods. The position is within the UKRI-CDT AI in Decision Making for Complex Systems.
Please share with potential candidates! π
24.11.2024 11:51
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Me talking to my algorithm⦠#meme
23.11.2024 07:57
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Discretisation memes! π
22.11.2024 07:04
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Would love to join! :)
21.11.2024 06:51
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I need to slowly move all my #mathematics #memes to the #mathsky. Letβs start with _Tolkien and convergence to stationarity_.
21.11.2024 06:48
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A few weeks ago, my student Alix Leroy and I were visiting Siemens Energy in Berlin for #knowledgeexchange and a guided tour around their production facilities. π
20.11.2024 18:16
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The random timestep Euler method and its continuous dynamics
ODE solvers with randomly sampled timestep sizes appear in the context of chaotic dynamical systems, differential equations with low regularity, and, implicitly, in stochastic optimisation. In this wo...
Say, you discretise an ODE with forward Euler choosing iid exponentially distributed stepsizes and linearly interpolate between discretisation points. Then, your interpolated path can be written as a continuous-time Markov process.
An analysis of this Markov process: arxiv.org/abs/2408.01409
19.11.2024 07:24
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Finding the Lyapunov function you are looking for = finding happiness. π
03.11.2023 15:38
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The really scary stuff to me are those with heavy tailsβ¦
02.11.2023 08:52
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Ever felt insecure about your own work? You are not alone.
Gauss in a letter to Bessel:
βWhen I am new to a subject, I distrust my own notions - especially if they contradict Laplace.β
(from W. Ahrens: βScherz und Ernst in der Mathematikβ, Teubner, Leipzig 1904.)
30.10.2023 14:09
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Hi #mathsky and everyone!
My name is Jonas, I do applied maths for living β usually solving problems that concern data, uncertainties, or both. I am based at the University of Manchester, UK.
28.10.2023 20:41
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