Superposition: Being in Many States at Once
A quantum system need not be in one state or another but can be in a blend of both, in...
Month: July 2026
The Measurement Problem
Between measurements, a quantum system evolves smoothly through many possibilities at once. Yet every measurement finds it in just one...
Maxwell’s Demon: Information and the Second Law
Imagine a tiny being that sorts fast molecules from slow, seeming to create order for free and defy the second...
Least Action: Nature’s Economy
Of all the paths a system might take between two moments, it follows the one that makes a certain quantity...
Small-World Networks
In a huge web of connections, any two nodes may be surprisingly close. A few long-range links collapse the distances,...
The Church-Turing Thesis: What Computation Means
What does it mean to compute? A remarkable claim holds that every intuitive notion of mechanical calculation amounts to the...
Tractability: Why Some Problems Resist
A problem solvable in principle may be unsolvable in practice. If the effort required grows explosively with size, even modest...
Undecidability
Not every well-formed question has a computable answer. Some problems are undecidable, admitting no algorithm that settles every instance. The...
The Halting Problem: Limits of What Can Be Decided
Ask whether an arbitrary program will ever stop, and no general method can always answer. The question is not merely...
Compression as Intelligence
To understand is to describe briefly. A learner that finds the shortest account of its data has found its regularities,...
