# Eklavya Goyal

> I turn "this is a nightmare" into "why didn't we do this sooner?"

Physics × Math × ML - Machine Learning @ Tools for Humanity, based in Munich, DE. I turn "this is a nightmare" into "why didn't we do this sooner?"

## Pages

- [About](https://eklavyagoyal.com/about): who I am, the physics→ML path
- [Work](https://eklavyagoyal.com/work): projects and research
- [The Lab](https://eklavyagoyal.com/lab): ~19 interactive physics & ML experiments, each a hand-built simulation
- [Writing](https://eklavyagoyal.com/writing): essays and notes (RSS at https://eklavyagoyal.com/feed.xml)
- [Timeline](https://eklavyagoyal.com/timeline): my life rendered as a git log
- [Contact](https://eklavyagoyal.com/contact): how to reach me
- [For agents](https://eklavyagoyal.com/agents): this machine-readable surface, explained

## Projects

- [Proof of Personhood at Scale](https://eklavyagoyal.com/work/proof-of-personhood): Machine-learning systems that help verify a unique human without surveilling them, privacy-preserving models running at planetary scale. (2024 →, Tools for Humanity)
- [Physics-Informed Learning](https://eklavyagoyal.com/work): Neural networks with the laws of physics baked into the loss, models that respect conservation laws instead of fighting them. (2024, TUM)

## The Lab

- [Collapse](https://eklavyagoyal.com/collapse): A site in superposition that resolves only when something conscious observes it. [quantum measurement]
- [The Mirror](https://eklavyagoyal.com/mirror): The observer effect, turned around: it watches how you move, then shows you the reflection. [observer effect]
- [The Learning Machine](https://eklavyagoyal.com/learn): A neural network learning live in your browser. Pick a shape; watch the boundary form. [machine learning]
- [Event Horizon](https://eklavyagoyal.com/horizon): Drag a black hole and watch it bend the light behind it into a ring. [general relativity]
- [Renormalization](https://eklavyagoyal.com/renormalization): Scroll from the cosmic web to a quark and back. The same law at every scale. [scale invariance]
- [Primordia](https://eklavyagoyal.com/primordia): Particles, a few simple rules, an interaction matrix: somehow it decides to become alive. [artificial life]
- [Munich](https://eklavyagoyal.com/munich): The U-Bahn I actually live on: the full network, as a map you can plan a real journey on. [the city]
- [Heat Death](https://eklavyagoyal.com/heat-death): Play Maxwell's demon. Sort the hot from the cold. Order isn't free; you pay in work. [thermodynamics]
- [First Light](https://eklavyagoyal.com/first-light): A cold start for the universe: the Big Bang to now, in fifteen seconds. [cosmology]
- [Determinism](https://eklavyagoyal.com/determinism): Two pendulums, identical to a thousandth of a radian, ending up in different lives. [chaos]
- [Morphogenesis](https://eklavyagoyal.com/morphogenesis): Reaction–diffusion you paint into; one rule, and the spots decide to happen. [pattern formation]
- [Slime Mold](https://eklavyagoyal.com/slime-mold): A brainless organism grows a trail network between Munich landmarks - and rediscovers the map. [emergence]
- [Fourier](https://eklavyagoyal.com/fourier): Draw any closed shape; a chain of rotating circles redraws it. Any path is a sum of circles. [harmonics]
- [Cymatics](https://eklavyagoyal.com/cymatics): Drag a frequency; a Chladni plate finds the standing wave in sand, and you hear the tone. [resonance]
- [Worldline](https://eklavyagoyal.com/worldline): Your life on a spacetime diagram. Drag to boost the frame; the light cone never moves. [special relativity]
- [Tesseract](https://eklavyagoyal.com/tesseract): A four-dimensional cube, rotating in 4D and projected to your screen. A shadow of a higher dimension. [geometry]
- [Double-Slit](https://eklavyagoyal.com/double-slit): Fire quanta one at a time; they interfere with themselves. Look at which slit, and the fringes die. [quantum]
- [Gravity](https://eklavyagoyal.com/gravity): A universe you build by hand. Drop a star, fling one into orbit, watch a galaxy fall out of a cold cloud. [n-body gravity]
- [Hyperbolic](https://eklavyagoyal.com/hyperbolic): A plane with too much room. Regular tilings flat space forbids, in the Poincaré disk - drag to walk where the edge is infinitely far. [non-Euclidean geometry]

## Writing

- [Identity is a coordinate system](https://eklavyagoyal.com/writing/identity-is-a-coordinate-system): Proof of personhood handed me the oldest question in philosophy with an engineer's deadline attached: what about you stays invariant when everything else transforms?
- [Deep learning rediscovered renormalization](https://eklavyagoyal.com/writing/deep-learning-rediscovered-renormalization): Coarse-graining was a physicist's trick for throwing away exactly the right details. Then I watched a network learn to do it on its own, and stopped trusting the coincidence.
- [The lab is how I stay honest](https://eklavyagoyal.com/writing/the-lab-is-how-i-stay-honest): I keep a room of physics toys on this site. They are not a portfolio. They are a device for catching myself when I only think I understand something.
- [The papers that rewired me](https://eklavyagoyal.com/writing/the-papers-that-rewired-me): Not the canon, not a syllabus. A short and opinionated list of the work that actually changed how I think about learning systems, with the why.
- [A piece of golden chalk](https://eklavyagoyal.com/writing/golden-chalk): Three years after moving to Germany with no German, I won the department's Golden Chalk for the best tutorial: one tutor a year, and that year it was mine, for Real Analysis 1.
- [Physics-Informed Neural Networks](https://eklavyagoyal.com/writing/physics-informed-neural-networks): The writeup of a talk I gave at TU München: putting a differential equation inside the loss function, and three solvers built that way, a damped oscillator (forward, then inverted for an unknown parameter) and the heat equation in 1D and 2D.

## Machine-readable API

CORS-open JSON, no auth, served from the same content registries:

- https://eklavyagoyal.com/api/now: who I am and what I'm building right now
- https://eklavyagoyal.com/api/projects: the projects registry
- https://eklavyagoyal.com/api/lab: the lab experiments index
- https://eklavyagoyal.com/feed.xml: the writing, as RSS

A digital twin (Eigen) answers questions on this site, grounded only on this
same data and tested not to invent; it is same-origin, so it is for people,
not agents. For programmatic use, the JSON above is the honest surface.

## Links

- GitHub: https://github.com/eklavyagoyal
- LinkedIn: https://www.linkedin.com/in/eklavya-goyal