Petri Laarne

• Doctoral researcher (PhD student, 2022–) in mathematics at University of Helsinki.
• Occasional software developer.
• Secretary of the Finnish Mathematical Society (2023–).
• Yleistajuista matikkaa suomeksi: Nollakohta.fi.

Contact details:

• Languages: suomi, English, français, svenska (in rough order of fluency).
• Office: Exactum B315.
• Email: [email protected].
• Mastodon: @[email protected].

Research

I am interested in stochastic analysis: partial differential equations with a dash of randomness. Generally speaking, I like when stuff has a random component in it. My research is on nonlinear wave equations, Euclidean quantum field theories, and stochastic quantization.

For a good* introduction to my research topic, I suggest looking at my MSc thesis Periodic nonlinear Schrödinger equation (2021).

As part of my civilian service, I worked as a research assistant at the Institute for Atmospheric and Earth System Research at University of Helsinki. My research was on statistical methods to explore many-variable data sets.

*This might be a biased statement.

Publications

• Publications on ORCiD: 0000-0002-9044-8583.
• Preprints on arXiv.
• Published papers also archived on University of Helsinki research portal.

Preprints as of 17 March 2024:

• Barashkov and Laarne: Invariance of φ⁴ measure under nonlinear wave and Schrödinger equations on the plane (arXiv).

Atmospheric data analysis papers from my civilian service:

• Laarne, Amnell, Zaidan, Mikkonen, Nieminen: Exploring Non-Linear Dependencies in Atmospheric Data with Mutual Information (2022, Atmosphere, MDPI)
• Laarne, Zaidan, Nieminen: ennemi: Non-linear correlation detection with mutual information (2021, SoftwareX, Elsevier)

Software

• ennemi: a Python package to explore non-linear correlations across variables. Developed as part of my work at INAR, now also used on multiple other research fields.

Teaching

At University of Helsinki:

• Responsible teacher for Advanced LaTeX, a PhD-level course in mathematical typesetting, May 2024. (Course page.)

Previously as a teaching assistant:

• Todennäköisyyslaskenta II (2023), development of STACK exercises.
• Todennäköisyyslaskenta II (2022), weekly guidance sessions.
• Lukiomatematiikan kertaus (2021), development of self-study STACK exercises.
• Todennäköisyyslaskenta II (2019), weekly exercise sessions.

I may be available for BSc thesis supervision (analysis and probability in broad sense) at University of Helsinki.