The map of the library
The library sits on four broad shelves — how we know things, the physical world, the living world, and the world people built. On each shelf live the disciplines, each asking a different question. The boundaries are blurry on purpose: the most interesting work often happens where two fields meet.
The Physical World
How do matter, energy, and space behave?Chemistry
“How do substances combine and change?”
What stuff is made of and how it rearranges — atoms, bonds, reactions, and the periodic patterns of the elements.
Physics
“How do matter and energy behave?”
The rules underneath everything else: motion, forces, energy, and the particles and fields that make up the universe.
Earth & Space
“How do planets, oceans, and stars work?”
Our planet and the cosmos it sits in — geology, weather, oceans, and where astronomy meets the rest of science.
The Living World
How does life work?Biology
“How does life work?”
Living systems from molecules to ecosystems — cells, genes, organisms, and how they grow, reproduce, and evolve.
The Human World
How does the world people built work?Economics
“How do money and trade shape the world?”
Money, markets, and who has what — how value moves around, and why it piles up where it does.
Technology
“How do the machines we built actually work?”
Computers, networks, and the companies behind them — how the digital world runs and who runs it.
Where does astronomy fit?
Astronomy is the study of everything beyond Earth. It isn't really a separate branch so much as physics and chemistry applied at the largest scales — hence astrophysics (how stars burn and galaxies move) and astrochemistry (what space is made of). We file it under Earth & Space.
The scale ladder
From the tiniest particles to the whole universe — every rung is a scale of nature. Click a rung to see which fields study it. Notice how they overlap: physics runs top to bottom, while chemistry and biology share the middle.
The scale ladder
larger ↑~10⁻¹⁰ m
Atoms
The smallest unit of an element.
Studied by
- Where physics meets chemistry: physical chemistry
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