Physics, Pixelated

Cold atom cloud merging into a single glowing wave in a laser trap

Bose and Einstein: What Is a Bose–Einstein Cond...

A Bose–Einstein condensate is a dilute gas of bosons cooled until a macroscopic number share the same quantum ground state. Bose’s 1924 photon statistics and Einstein’s extension set the idea;...

Bose and Einstein: What Is a Bose–Einstein Cond...

A Bose–Einstein condensate is a dilute gas of bosons cooled until a macroscopic number share the same quantum ground state. Bose’s 1924 photon statistics and Einstein’s extension set the idea;...

Coil and magnet, a crackling AC motor and arcs of field lines in a Victorian laboratory

Faraday, Maxwell and Tesla: Who Did What in Ele...

Electromagnetism was not one inventor’s story. Faraday made induction a laboratory fact, Maxwell turned fields into equations that predicted light, and Tesla patented a practical AC motor. Here is who...

Faraday, Maxwell and Tesla: Who Did What in Ele...

Electromagnetism was not one inventor’s story. Faraday made induction a laboratory fact, Maxwell turned fields into equations that predicted light, and Tesla patented a practical AC motor. Here is who...

Black hole with faint Hawking radiation drifting away over a dark plain

Stephen Hawking: What Did He Predict, and What ...

Hawking’s 1974 prediction that black holes radiate is central theoretical physics — and still unobserved in astrophysical black holes. Analogue experiments are not detections. The information paradox is open. Penrose’s...

Stephen Hawking: What Did He Predict, and What ...

Hawking’s 1974 prediction that black holes radiate is central theoretical physics — and still unobserved in astrophysical black holes. Analogue experiments are not detections. The information paradox is open. Penrose’s...

Fermions each alone in separate alcoves beside bosons piled together in one bright pool

What Is the Spin–Statistics Theorem?

The spin–statistics theorem ties a particle’s spin to the symmetry of its quantum state. Integer spin → bosons (symmetric); half-integer spin → fermions (antisymmetric). Fierz (1939) and Pauli (1940) made...

What Is the Spin–Statistics Theorem?

The spin–statistics theorem ties a particle’s spin to the symmetry of its quantum state. Integer spin → bosons (symmetric); half-integer spin → fermions (antisymmetric). Fierz (1939) and Pauli (1940) made...

Foucault pendulum swinging over a ring of pegs in a domed hall

How Does a Foucault Pendulum Prove Earth Rotates?

A long pendulum’s swing plane slowly turns relative to the floor. Foucault showed in 1851 that the turn is Earth’s rotation made visible. The rate is 360° times the sine...

How Does a Foucault Pendulum Prove Earth Rotates?

A long pendulum’s swing plane slowly turns relative to the floor. Foucault showed in 1851 that the turn is Earth’s rotation made visible. The rate is 360° times the sine...

A golden foreground galaxy encircled by a thin blue Einstein ring of lensed light from a galaxy directly behind it

How Does Gravity Bend Light? Einstein Rings and...

Gravity bends light because spacetime is curved. The 1919 eclipse measured the Sun’s deflection; Einstein’s 1936 note foresaw stellar lenses; modern telescopes image Einstein rings. Here is the physics without...

How Does Gravity Bend Light? Einstein Rings and...

Gravity bends light because spacetime is curved. The 1919 eclipse measured the Sun’s deflection; Einstein’s 1936 note foresaw stellar lenses; modern telescopes image Einstein rings. Here is the physics without...