The First Three Minutes: Where the Lightest Elements Come From
The universe's first minutes ran a brief burst of nuclear fusion. How Big Bang nucleosynthesis predicted the hydrogen and helium we still measure today.
Signals
Cosmos
Essays on black holes, string theory, cosmology, and the physics of information, written with real math, for readers who want more than metaphors.
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In this signal
Pulsars: dead stars that keep the universe's best time
From a 1967 squiggle on a Cambridge chart recorder to a galaxy-sized gravitational-wave detector: how pulsars became the universe's most reliable clocks.
Feynman's path integral: how a particle takes every path at once
Richard Feynman's path integral says a particle takes every route from A to B at once. How summing paths recovers the classical world, tunneling, and QFT.
The universe's strictest filing system: black holes and information
Black hole entropy scales with area, not volume: the fact that launched the holographic principle and a decades-long argument over lost information.
The Higgs field: where elementary particles get their mass
How the Higgs field, nonzero even in empty space, gives elementary particles their mass, and why the boson found at CERN in 2012 was the proof it exists.
Laplace's demon: the clockwork universe and how it broke
Laplace imagined an intellect that could compute the entire future. Quantum mechanics and chaos theory dismantled the idea in two independent ways.
South of the South Pole: why 'before the Big Bang' may be the wrong question
What came before the Big Bang? Hawking argued it's as meaningless as asking what's south of the South Pole. A tour of the Hartle–Hawking no-boundary idea.
The universe's baby pictures keep getting sharper: JWST at the cosmic dawn
JWST keeps finding galaxies earlier and brighter than models predicted. What it reveals about the cosmic dawn, and why the tension is real.
The arrow of time: why the future looks different from the past
Physics runs the same forwards and backwards, yet time flows one way. The reason is a single idea: entropy. A clear tour of the arrow of time.
A hundred spacetime tremors a year: gravitational-wave astronomy comes of age
Ten years ago, one gravitational wave won a Nobel. Now LIGO–Virgo–KAGRA catch them by the hundreds: how ripples in spacetime became routine astronomy.
A visitor from beyond: what comet 3I/ATLAS is (and isn't)
Comet 3I/ATLAS is only the third object confirmed from beyond our solar system. What we know, and how it reopens Fermi's question: where is everybody?
Quantum, now visible: the 2025 Nobel and the tunneling that built the qubit
The 2025 Physics Nobel: proof that a circuit you can hold tunnels through a barrier and occupies quantized energy levels, the seed of the qubit.
Is dark energy changing its mind? DESI and Einstein's returning 'blunder'
For a decade dark energy looked constant. New DESI data hints it may be weakening over cosmic time, reviving Einstein's abandoned cosmological constant.