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Ryan Collison

I write about cool science and share it here.

Dyson swarm megastructure surrounding distant star with infrared waste heat signature

Dysonian SETI: Looking for Megastructures Instead of Messages

Series: Technosignatures | Part: 2 of 9 In 1960, Freeman Dyson published a two-page paper in Science that changed SETI forever. His argument was deceptively simple: forget listening for radio signals. If you want to find advanced civilizations, look for their engineering. The logic was thermodynamic. Any civilization that continues

Radio telescope array analyzing electromagnetic signals from deep space

Beyond Little Green Men: The Scientific Search for Alien Technology

Series: Technosignatures | Part: 1 of 9 In 1960, Frank Drake pointed a radio telescope at two nearby stars and listened. For three months, he heard nothing but cosmic static. The project, dubbed Ozma after the queen of Oz, was the first systematic attempt to detect alien intelligence. It failed spectacularly.

Coherence as persistent topological structure across neural scales

Synthesis: What Topology Teaches About the Shape of Coherence

Series: Topological Data Analysis in Neuroscience | Part: 9 of 9 We’ve traveled through nine dimensions of topological neuroscience—from persistent homology’s mathematical machinery to the Blue Brain Project’s eleven-dimensional cavities, from consciousness arising in geometric complexity to clinical disorders showing topological scars. Now we synthesize. What

Topological biomarkers distinguishing healthy from disordered brain states

Clinical TDA: Topological Biomarkers for Brain Disorders

Series: Topological Data Analysis in Neuroscience | Part: 8 of 9 Psychiatry has a measurement problem. We diagnose based on symptoms—clusters of behaviors, subjective reports, clinical observation. But symptoms don’t respect clean categories. Depression bleeds into anxiety. Bipolar looks like ADHD during certain phases. Trauma produces symptoms that overlap

Topology and information geometry converging on neural structure

TDA Meets Information Geometry: Two Approaches to Neural Structure

Series: Topological Data Analysis in Neuroscience | Part: 7 of 9 Two mathematical frameworks. Two ways of seeing brain geometry. Both reveal structure invisible to classical methods. But they see different things—or do they? Topological data analysis extracts holes, loops, cavities. It counts connected components, measures persistence, tracks features that

Neural manifold transformation during learning visualized topologically

Learning in Topological Space: How Neural Manifolds Transform

Series: Topological Data Analysis in Neuroscience | Part: 6 of 9 You practiced. You got better. Something changed in your brain. But what changed? At the geometric level, what does learning actually do to neural activity patterns? The standard story: synapses strengthen or weaken. Neurons that fire together wire together (Hebbian

Brain network topology revealing higher-order structure beyond pairwise connections

Brain Networks Through a Topological Lens

Series: Topological Data Analysis in Neuroscience | Part: 5 of 9 Your brain is not one thing. It’s a network of networks—distinct regions, specialized systems, distributed coalitions that form, dissolve, and reform depending on what you’re doing, thinking, or feeling. Neuroscience has known this for decades. But how