Research

Thesis

Most people accept the concept of randomness in the world. What if randomness was just a lack of information, a concept that only actually affects the minority of physics of our world? If we refuse this for just a second, it becomes evident that we merely need the pieces to solve our puzzle. After all, as you place more and more pieces into a puzzle, the picture does grow clearer.

Mathematics has its beauty. As does its application to financial time series. I have applied a vast number of branches in order to grow ever-closer to completing the puzzle. And the beauty of what I have found is overwhelming.

— Cormac Lydon

Mathematical Domains

Information Geometry & Statistical Manifolds

The Fisher-Rao metric on the space of probability distributions induces non-zero curvature. We exploit the divergence between Euclidean and Riemannian computations as a novel class of trading signals.

Amari, S. Information Geometry and Its Applications. Springer, 2016.

Amari, S. Differential-Geometrical Methods in Statistics. Springer, 1985.

Nielsen, F. An Elementary Introduction to Information Geometry. MDPI, 2020.

Čencov, N. N. Statistical Decision Rules and Optimal Inference. AMS, 1982.

Atkinson, C. and Mitchell, A. F. S. “Rao’s distance measure.” Sankhyā, 1981.

Riemannian Geometry & Geodesic Methods

Geodesic regression, Fréchet means, and parallel transport on the Gaussian manifold. Parameter decay rates explained by holonomy accumulation via the Ambrose-Singer theorem.

do Carmo, M. P. Riemannian Geometry.Birkhäuser, 1992.

Pennec, X. “Intrinsic statistics on Riemannian manifolds.” J. Math. Imaging Vision 25(1), 2006.

Fletcher, P. T. “Geodesic regression and the theory of least squares on Riemannian manifolds.” IJCV 105(2), 2013.

Karcher, H. “Riemannian center of mass and mollifier smoothing.” Comm. Pure Appl. Math. 30, 1977.

Stochastic Calculus & Volatility Modeling

Jump-diffusion processes, local and stochastic volatility surfaces, rough volatility, and realized variance decomposition applied to futures markets.

Gatheral, J., Jaisson, T., and Rosenbaum, M. “Volatility is rough.” Quantitative Finance 18(6), 2018.

Hamilton, J. D. “A new approach to the economic analysis of nonstationary time series and the business cycle.” Econometrica 57(2), 1989.

Dahlhaus, R. “Fitting time series models to nonstationary processes.” Annals of Statistics 25(1), 1997.

Topological Data Analysis

Persistent homology and Betti curves for identifying structural invariants in high-dimensional price data that persist across temporal scales.

Gidea, M. and Katz, Y. “Topological data analysis of financial time series: Landscapes of crashes.” Physica A 491, 2018.

Baitinger, E. and Flegel, S. “The better turbulence index? Forecasting adverse financial markets regimes with persistent homology.” Financial Markets and Portfolio Management 35, 2021.

Spectral Analysis & Random Matrix Theory

Marchenko-Pastur eigenvalue filtering for covariance estimation, signal-noise separation, and spectral methods including Fourier and Hilbert-Huang decomposition.

Laloux, L., Cizeau, P., Bouchaud, J.-P., and Potters, M. “Noise dressing of financial correlation matrices.” Physical Review Letters 83(7), 1999.

Optimal Transport & Wasserstein Geometry

Distribution-level distance metrics for regime classification, non-parametric signal construction, and gradient flow models of distributional evolution.

Otto, F. “The geometry of dissipative evolution equations: The porous medium equation.” Comm. Partial Differential Equations26(1–2), 2001.

Villani, C. Optimal Transport: Old and New. Springer, 2009.

Path Signatures & Rough Path Theory

Iterated integral features capturing the geometry of sequential price paths, providing feature-invariant encodings for strategy selection.

Lyons, T. J. “Differential equations driven by rough signals.” Revista Matemática Iberoamericana 14(2), 1998.

Kidger, P. and Lyons, T. “Signatory: Differentiable computations of the signature and logsignature transforms.” arXiv:2001.00706, 2021.

Discrete Ricci Curvature & Network Geometry

Ollivier-Ricci and Forman-Ricci curvature on correlation networks, with discrete Ricci flow for detecting structural fragmentation preceding regime transitions.

Ollivier, Y. “Ricci curvature of Markov chains on metric spaces.” J. Functional Analysis 256(3), 2009.

Samal, A. et al. “Network geometry and market instability.” Royal Society Open Science 8(2), 2021.

Hamilton, R. S. “Three-manifolds with positive Ricci curvature.” J. Differential Geometry 17(2), 1982.

Perelman, G. “The entropy formula for the Ricci flow and its geometric applications.” arXiv:math/0211159, 2003.

Non-Stationary Dynamics & Model Lifecycles

Locally stationary processes with measurable validity horizons. The bias-variance tradeoff inverts under non-stationarity: deliberately local models with matched lifecycles dominate generalized models.

Bailey, D. H. et al. “The probability of backtest overfitting.” J. Computational Finance 20(4), 2017.

López de Prado, M. Advances in Financial Machine Learning. Wiley, 2018.

Lo, A. W. Adaptive Markets: Financial Evolution at the Speed of Thought. Princeton, 2017.

Politis, D. N. and Romano, J. P. “The stationary bootstrap.” JASA 89(428), 1994.

Fan, J. and Gijbels, I. Local Polynomial Modelling and Its Applications. Chapman & Hall, 1996.

Publications

Divergence Signals: Exploiting the Gap Between Euclidean and Riemannian Structure in Financial Time Series

Cormac Lydon · Lydon Quantitative Research · April 2026

Introduces seven divergence predicates measuring the gap between flat-space and curved-space computations on rolling windows of financial time series. Proves non-triviality for all empirically observed return distributions, connects parameter decay to holonomy via the Ambrose-Singer theorem, and establishes minimax optimality of daily recalibration.

The Overfitting Edge: Optimal Model Lifecycles Under Non-Stationary Market Dynamics

Cormac Lydon · Lydon Quantitative Research · April 2026

Shows that under non-stationary dynamics with measurable validity horizons, the classical bias-variance tradeoff inverts: deliberately overfit models with matched lifecycles provably dominate generalized models. Formalizes a non-stationary bias-variance decomposition and proves that standard cross-validation conflates noise overfitting with regime fitting.

Systems

LQ Trading Factory

Autonomous strategy factory for CME futures. The system mines, validates, deploys, and discards strategies on a daily cycle — each calibrated to local market dynamics and replaced before its validity horizon expires. Mathematical signal generation spans multiple branches of pure and applied mathematics.

LQ-Predict

Prediction market and sports analytics platform. Integrates multiple probabilistic models for event forecasting across prediction markets and sports, with bankroll management informed by information-theoretic sizing criteria.