Arjun Balaji
Interesting problems resist jurisdiction. I follow them across ML, markets, and the machinery of public systems.
Current Focus

Access Accounting

A framework for measuring AI compute access disparities across geographies and institutions.

[working paper]

SENTINEL

AI early warning system for financial crises in frontier markets.

[working paper]

[stealth]

ARG Lab

AI audio-based cognitive assessment at Columbia's Butler Aging Center.

[active]

Impact AI Foundry

AI capacity-building for nonprofits in Bangalore.

[active]
Recent Writing
On the Unreasonable Effectiveness of Thinking in Structures [essay] misc The thing about Gödel [note] misc

Research

Alignment & Values

Encoding Values: Injecting Morality into Machines via Prompt-Conditioned Moral Frames

How you frame a moral question to a model shapes its answer in systematic, measurable ways.

[NeurIPS 2025]

Working paper on normative pluralism and alignment

What happens when "aligned" means different things to different moral communities.

[working paper]

// this page is also a value-laden artifact

Interpretability

Spectral and Geometric Signatures for Scalable Reasoning Verification

Chain-of-thought traces have structure; this project makes that structure auditable using graph Laplacian spectral features and Wasserstein gradient flows to detect incoherent or deceptive reasoning without model-internal access.

[ICLR 2026] [NeurIPS 2026 in prep] [✦]

signal detected.

this work was selected for external compute support
to scale what's already working.

the geometry of reasoning is not flat.
think: optimal transport, probability flows,
the shape of a thought moving through embedding space.

if that sentence made sense to you:
→ /research#laplacian

Fairness & Auditing

BiasCheck

Open-source framework for detecting contextual bias in text, models, RAG pipelines, and databases.

[AAAI 2025]

Access Accounting

Measuring compute access disparities across geographies and institutions using the AAR schema and ECA metric.

[working paper] [ICML submission]

Macro-Financial Systems

SENTINEL

Fusing macro panel data with multilingual NLP, XGBoost+SHAP, Temporal Fusion Transformers, and GNNs to predict currency and sovereign debt crises before they cascade.

[working paper]

Biomedical ML

ProteoDockNet

GNN that predicts ligand binding affinities for 30 human proteins from SMILES strings, outperforming regression baselines.

[Elsevier 2024]

Brain MRI Surface Registration

Unsupervised mesh deformation for cortical surface registration, in collaboration with Harvard Medical School.

[CMU · 2024–25]

3D Cardiac Segmentation

Volumetric cardiac segmentation at NTU's MVAIT Lab.

[NTU · 2024–25]

“The graph Laplacian of a reasoning trace is, in some sense,
a fingerprint of how a mind moves. Eigenvalues don’t lie.
They just describe.”

“This is the thing we’re building: not a judge, but a mirror.”

// supported by SAAR × AIM Intelligence Compute Grant
// open-source toolkit releasing May 2026

Work

[stealth]

SENTINEL

Predicting financial crises in frontier markets before they become front pages.

The interesting problem: most macro models are linear; crises are phase transitions.

[working paper · active]

Impact AI Foundry

AI capacity-building for nonprofits in Bangalore.

The interesting problem: most AI tooling assumes data infrastructure that doesn’t exist in the sector.

[active]

BiasCheck

Python library for contextual bias detection across the full ML stack.

The interesting problem: bias isn’t a property of a model, it’s a property of a model in context.

[open source · published]

ProteoDockNet

Drug discovery tooling for researchers without specialized hardware.

The interesting problem: SMILES strings are sequences but molecules are graphs.

[open source · published]

Notes & Essays

[essay] misc

On the Unreasonable Effectiveness of Thinking in Structures

There’s a moment in most hard problems where the notation saves you. Not the idea. The notation. You write down the right symbols, and suddenly the structure of the problem is visible in a way it wasn’t when it lived only in your head.

This is what I mean when I say I think computationally. Not that I reach for code first. I reach for structure. I want to know the objects, the operations, the invariants. What stays the same when everything else changes? What breaks when you push on it? These are questions a mathematician asks, but they’re also questions an engineer asks, and a policy analyst, and a doctor reading an ECG. The frame is the same. The domain is an implementation detail.

I came to this through an unlikely path. I started in telecommunications engineering. A field obsessed with the precise degradation of signals, with noise and channel capacity and the fundamental limits of transmission. Claude Shannon sitting down in 1948 and essentially inventing information theory from first principles. The elegance of that: that you could bound what’s knowable, mathematically, before you ever build the system.

That sensibility stayed with me when I moved into machine learning. The best ML papers aren’t really about models. They’re about what the model reveals about the structure of the problem. A good architecture is a hypothesis about the world. When a graph neural network outperforms a CNN on protein binding prediction, it’s not just a benchmark win. It’s evidence that molecular structure is better represented as a relational system than a grid. The math is telling you something.

The same thing happens in policy. The reason I find macro-financial systems interesting isn’t the economics. It’s that they’re complex adaptive systems with feedback loops, phase transitions, and emergent failure modes that look nothing like the sum of their parts. A currency crisis isn’t a big version of a small problem. It’s a qualitatively different regime. You need different math. And the reason most early warning systems fail isn’t that they lack data. It’s that they’re applying linear thinking to a nonlinear system.

I don’t think there’s a clean line between technical and non-technical problems. I think there are problems where the structure is visible and problems where it’s hidden, and the work is usually to find a representation that makes the structure legible. Sometimes that’s a transformer architecture. Sometimes it’s a well-specified decision rule. Sometimes it’s just the right variable name.

The unreasonable effectiveness of mathematics in the natural sciences (Wigner’s phrase) always felt to me like it was pointing at something deeper than coincidence. The world has structure. Thinking in structures finds it. That’s the whole game.

[note] misc

The thing about Gödel

Everyone who learns about Gödel’s incompleteness theorems goes through the same arc: confusion, then awe, then a period of over-applying it to everything (“you can’t prove your own axioms, man”). The third phase is embarrassing in retrospect.

But the actual insight, that any sufficiently powerful formal system contains true statements it cannot prove, is genuinely strange and worth sitting with. It means completeness and consistency can’t coexist past a certain threshold of expressiveness. The more your system can say, the more it contains truths it can’t reach.

I think about this a lot when working on alignment. A model trained on human feedback is a formal system of sorts. It has a grammar. It has inference rules. It has things it will say and things it won’t. The question isn’t whether it’s aligned. It’s whether alignment is even a complete specification. Whether there are values the system should have that no training process can fully reach.

Probably not a productive line of thought at 2am. But here we are.

About

I’m a first-year MPA student at Columbia SIPA concentrating in Technology Policy, and a researcher with a background in ML systems. My work spans value alignment in language models, mechanistic interpretability, AI fairness auditing, and macro-financial early warning systems. Before Columbia, I did research stints at CMU, NTU Singapore, IISc Bangalore, and Samsung Research.

Right now I’m finishing a paper on compute access disparities in AI (targeting ICML), doing audio-based cognitive assessment research at Columbia’s Butler Aging Center, and working on some things I can’t talk about yet.

Outside of work: kendo, retro games (currently: God of War on PSP), and an unhealthy interest in how complex systems fail.

drag to rearrange

“The Library of Babel contains every book that has ever been written, and every book that ever could be. Most of them are nonsense. This one might be too.”

— a note to whoever got here

[enter the library →]

Atlas

// the adjacency matrix of a life, or: every node is a fixed point of some contraction mapping

institution
research
project
writing
concept

“This page exists. It just can’t be proven from within this system.”

← back to a provable page