Computational Physicist // AI Safety // Musician

Marios Tsatsos

Modelling quantum many-body systems with coupled PDEs and HPC. Probing LLM residual streams for mechanistic interpretability. Co-developer of MCTDH-X. Playing saxophone when the terminal is idle.

Research Projects Google Scholar
Research

Physics, AI Safety, Machine Learning

Current // AI Safety

Probing Harmful Intent in LLM Residual Streams

Linear probes on transformer residual stream activations detect harmful prompt intent with AUC 0.974 at layer 13. 2x2 factorial design disentangling prompt semantics from output harmfulness.

2025GitHubarXiv
Phys. Rev. X // Rice + Sao Paulo + Vienna

Parametric Excitation of a BEC: Faraday Waves to Granulation

Shaken BECs produce Faraday wave patterns and granular splinters from quantum correlations. Benchmarked MCTDH-X against experiment. Dynamics beyond mean-field.

Phys. Rev. X 9, 011052 (2019)Paper
Physics Reports // 52-page review

Quantum Turbulence in Trapped Atomic Bose-Einstein Condensates

First-authored comprehensive review. Vortices, dynamics, turbulent behaviour in ultracold gases. Theory through experimental frontiers.

Phys. Rep. 622, 1-52 (2016)arXiv
Press

Coverage

Phys.org

Matter waves and quantum splinters
ScienceDaily

Physicists shatter BEC, get different pieces every time
Rice University

Matter waves and quantum splinters
FinTech Magazine

Which Way Now for Generation Rent?
Publications

Selected papers

2025
Probing Harmful Prompts in LLM Residual Streams
arXiv:2506.10805
M. C. Tsatsos
arXivCode
2019
Parametric Excitation of a BEC: Faraday Waves to Granulation
Physical Review X 9, 011052
Nguyen, Tsatsos, Luo, Lode, Telles, Bagnato, Hulet
Paper
2019
Correlations of Strongly Interacting 1D Dipolar Few-Boson Systems
New Journal of Physics 21, 033030
Chatterjee, Tsatsos, Lode
2019
Non-Penrose BEC With Spinor Condensates in Optical Lattices
New Journal of Physics 21, 053044
Dutta, Tsatsos, Basu, Lode
2018
Correlated Many-Body Quantum Dynamics of Driven 1D Bose Gas
Physical Review A 97, 043625
Roy, Gammal, Tsatsos, Chatterjee, Chakrabarti, Lode
2017
Phantom Vortices: Hidden Angular Momentum in Ultracold BECs
Scientific Reports 7, 40122
Weiner, Tsatsos, Cederbaum, Lode
Paper
2016
Quantum Turbulence in Trapped Atomic BECs
Physics Reports 622, 1-52
Tsatsos, Tavares, Cidrim, Fritsch, Caracanhas, dos Santos, Barenghi, Bagnato
arXiv
2016
Vortex Dynamics: Crossover From 2D to 1D in Elongated BECs
Physical Review A 94, 023627
Tsatsos, Edmonds, Parker
2015
Vortex Reconnections in Anisotropic Trapped 3D BECs
J. Low Temp. Phys. 180, 133-143
Wells, Lode, Bagnato, Tsatsos
2015
Resonances and Dynamical Fragmentation in a Stirred BEC
J. Low Temp. Phys. 181, 171-181
Tsatsos, Lode
2014
The Attractive Bose Gas in 2D: Fragmentation and Collapse
Physical Review A 89, 043604
Tsatsos
2011
Attractive BECs in 3D Under Rotation: Stability of the Ground State
Physical Review A 83, 063615
Tsatsos, Streltsov, Alon
2008
An Introduction to Topos Physics
arXiv:0803.2361 // MSc, Imperial College London
Tsatsos
arXiv
2008
The Van der Pol Equation
arXiv:0803.1658 // Non-linear dynamics
Tsatsos
arXiv
Background

Education and Affiliations

PhD Computational Physics

Heidelberg University

Theoretical Chemistry, Cederbaum Group. Ultracold quantum gases, MCTDH-X.

MSc Quantum Fields and Strings

Imperial College London

Topos physics. Category theory applied to quantum mechanics.

Postdoc

University of Sao Paulo

FAPESP-funded. Quantum turbulence, vortex dynamics, BEC theory.

Visiting // Invited

Harvard ITAMP, Rice, Los Alamos, BIRS

ICAP Seoul, LT28, BEC 2017, MCTDH Paris, Santa Fe, Oaxaca, Havana.

Projects

Software and Tech

Probing Harmful Prompts

Linear probes on LLM residual stream activations. 2x2 factorial design. AUC 0.974 at layer 13.

PythonPyTorchTransformersMech. Interp.
GitHub >

MCTDH-X

Co-developed the MultiConfigurational Time-Dependent Hartree solver. Used in 60+ papers. GUI, docs, community.

FortranHPCPDE ModellingMPI
ultracold.org >

Udoma (Adjoin Homes)

Proptech venture, London hospitality. AWS infra, booking engine, SEO, CRM, property pipeline.

AWSWordPressSheets APICloudflare

Zele // WhatsApp AI Assistant

RAG assistant for property managers. WhatsApp Cloud API + Lambda. Structured JSON retrieval.

PythonRAGLambdaEmbeddings

Statistics, Calculus and Python Workshop

Co-authored book, Packt Publishing. Computational stats and calculus.

PythonNumPyEducation
Amazon >

AI/ML Summer Camp

Progressive Python notebooks. Fundamentals to neural networks. For students.

JupyterCurriculumEducation
Writing

Essays and Notes

Coming soon.

Physics, AI safety, philosophy of mind, dispatches from life.

Music

Jazz and Sound

Saxophone and clarinet. Jazz mostly. The part of life that equations don't reach. Though I once tried: early work on the Van der Pol oscillator included constructing sound files from Fourier spectra of periodic, quasi-periodic, and chaotic solutions.

SoundCloud
YouTube