Bayesian Inference for Non-linear Inverse Problems

Bayesian Inference for Non-linear Inverse Problems

🎙 Richard Nickl 👥 2K 📅 December 15, 2025 ⏱ 49 min 👁 351 📄 lecture 🧭 2026-08-15
Available in: English (current) Français

Keywords

inverse problemsBayesian inferenceGaussian processMCMCCalderón problem

Summary

In this lecture, Professor Richard Nickl addresses Bayesian inference for non-linear inverse problems, focusing on two examples: the Calderón problem (electrical impedance tomography) and polarized neutron tomography. He explains the mathematical formulation of these problems, the injectivity results (e.g., by Sylvester and Uhlmann for Calderón, and Paternain, Salo, and Uhlmann for non-abelian X-ray transforms), and the challenges posed by real data, which are discrete and noisy. He argues that classical optimization methods fail due to non-convexity and the roughness of noise, and proposes a Bayesian approach using Gaussian process priors. He describes the pCN algorithm (preconditioned Crank-Nicolson) as a practical MCMC method to compute posterior means, avoiding local optima. The talk emphasizes the theoretical justification and practical applicability of Bayesian methods for non-linear inverse problems.

125 words

Critical Evaluation

Value of the Information & Strength of the Argument

The talk provides valuable insights into the application of Bayesian methods to non-linear inverse problems, a topic of growing importance in applied mathematics and statistics. The argumentation is solid, building on rigorous mathematical results and illustrating with concrete examples. The speaker effectively motivates the need for Bayesian approaches by highlighting the limitations of classical optimization, and he presents the pCN algorithm as a practical solution. The discussion is well-structured and accessible to an audience with a background in mathematics or statistics.

Scientific Rigor, Source Quality, Title Accuracy

The talk demonstrates high scientific rigor, with references to seminal papers (e.g., Sylvester and Uhlmann 1987, Paternain et al. 2014) and recent experimental work published in Nature. The sources are credible and directly relevant. The title accurately reflects the content, and the talk stays on topic throughout. No comments were provided for analysis.

149 words

Title / Content Match

The title accurately reflects the content: the talk focuses on Bayesian methods for non-linear inverse problems, with examples and theoretical discussion.

Quality & Reliability

8/10

Talk by a leading expert (Professor at Cambridge) presenting rigorous mathematical results, with references to peer-reviewed publications (Annals of Mathematics, Nature). The content is technical and precise, but the presentation is a lecture, not a peer-reviewed article.

Key Moments

Cited Sources

  • INI Seminar Page — Official page for the seminar, providing details about the talk and the event.

Concurring Sources

  • Sylvester and Uhlmann (1987) — Paper establishing injectivity for the Calderón problem in dimensions ≥3.
  • Paternain, Salo, and Uhlmann (2014) — Paper proving injectivity for non-abelian X-ray transforms.

Contribution & Novelties

The talk provides a clear and rigorous exposition of Bayesian inference for non-linear inverse problems, emphasizing the practical advantages of MCMC methods over optimization. It bridges pure mathematics (injectivity results) and statistical practice, offering a general-purpose algorithm (pCN) that avoids local optima. The discussion of non-abelian X-ray transforms and the Calderón problem illustrates the breadth of applications.

Pour aller plus loin :

99 words

Radar Profile

The radar profile shows high scores in quality of information, technical level, and reliability, with a slightly lower score for quantity of information due to the lecture format. This indicates a dense, expert-level presentation with strong scientific foundations.

Reliability 8/10