Ben Fulcher
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bendfulcher.bsky.social
Ben Fulcher
@bendfulcher.bsky.social
I lead the Dynamics and Neural Systems Group at the School of Physics, the University of Sydney.
We develop time series tools & physical models to understand the dynamics of complex (usually neural) systems.

Also: @[email protected]
And there's an open python repo with really clear and easy to read and code implementing the key methods:
github.com/KieranOwens/...

Take a look?! 👀
GitHub - KieranOwens/tsdr: Time-series dimension reduction (TSDR)
Time-series dimension reduction (TSDR). Contribute to KieranOwens/tsdr development by creating an account on GitHub.
github.com
November 26, 2025 at 4:13 AM
Kieran explains how all the methods can be understood through these conceptual groupings, derives new relationships between existing methods, and provides some case-study demonstrations/comparisons of how insanely well they can work on data
November 26, 2025 at 4:13 AM
These powerful methods are underappreciated: A recent review of the field included *0* methods designed for time-series data, instead focusing on generic dimension reduction methods.

This paper assembles a diversity of >60 scientific methods for the first time, and unifies them across 7 categories.
November 26, 2025 at 4:13 AM
If you're interested in the statistics of time-irreversibility, and how they could be used to capture novel, interpretable properties from real-world time series, take a look:
arxiv.org/abs/2511.15991
(Code here: github.com/DynamicsAndN...)
Identifying statistical indicators of temporal asymmetry using a data-driven approach
The dynamics of time-reversible systems are statistically indistinguishable when observed forward or backward in time. A rich literature of statistical methods to distinguish irreversible dynamics fro...
arxiv.org
November 21, 2025 at 3:26 AM
The breath of comparison (of both methods and processes) also allowed us to demonstrate that all tested indices of irreversibility had weaknesses: i.e., we could always find an irreversibile process on which any given irreverisbility index will fail to detect irreversibility.
November 21, 2025 at 3:26 AM
We found key families of algorithmic constructions that were could accurately index irreversibility: (i) generalized autocorrelation functions; (ii) symbolic sequences; and (iii) forecasting-derived metrics. Some recapitulate concepts studied previously but in isolation; others are novel directions
November 21, 2025 at 3:26 AM
He we compared >6000 time-series metrics to index time reversibility from simulations of 35 different reversible and irreversible processes
November 21, 2025 at 3:26 AM
Quantifying time reversibility from data is important because it connects to concepts in thermodynamics (entropy production of non-equilibrium systems) & constrains the system's generative mechanisms (by ruling out linear dynamics; cf. related concepts of non-Gaussianity & nonlinearity)
November 21, 2025 at 3:26 AM