Hendrik Antoon Lorentz

Physicist — Hendrik Antoon Lorentz (Arnhem 1853 – Haarlem 1928) was a Dutch physicist, professor at Leiden and a leading figure of European physics at the turn of the twentieth century. He developed the theory of electrons, picturing matter as composed of charged particles in motion, and with it explained numerous optical and electromagnetic phenomena. To interpret the negative result of the Michelson-Morley experiment he introduced the Lorentz transformations and length contraction, providing the mathematical skeleton on which Einstein would later build special relativity. In 1902 he received the Nobel Prize in Physics, together with his pupil Pieter Zeeman, for the explanation of the Zeeman effect. He is also remembered for the Lorentz force, a fundamental law of electromagnetism describing the action of fields on a moving charge.

Trivia

Einstein held him in the deepest esteem and said that Lorentz had meant more to him than anyone else he had met in his life; at his funeral in 1928 the Dutch telegraph services were suspended for three minutes as a mark of mourning.

Theories and contributions

• Lorentz force — Force on a charge in electric and magnetic fields: $\vec{F}=q(\vec{E}+\vec{v}\times\vec{B})$.
• Lorentz transformations — Relations between coordinates of inertial frames that leave the speed of light invariant: $x'=\gamma(x-vt)$, with $\gamma=1/\sqrt{1-v^2/c^2}$.
• Length contraction — A moving body appears shortened along the direction of motion: $L=L_0\sqrt{1-v^2/c^2}$.

Present in chapters

17 18 20 Z

Linked atoms

23 linked atoms.

17 Il campo magnetico

• The Lorentz force
• Right-hand rule
• Uniform circular motion in a magnetic field
• The velocity selector
• The mass spectrometer
• The cyclotron
• The magnetic field and the tesla
• Laplace force on a wire
• The Hall effect
• Magnetism is electrostatics plus relativity
• The magnetic force does no work, and why that isn’t a paradox

18 Induzione elettromagnetica

• A charge and two points of view
• Faraday’s resolution

20 Relatività ristretta

• The ether and the Michelson-Morley experiment
• Time dilation
• The low-velocity limit
• Natural units
• The Lorentz transformations
• Relativistic momentum and the energy-momentum invariant

Z Appendice — Maturità

• Radioactive decay: nuclear physics, kinetics and relativity
• Photoelectron in a magnetic field: quantum physics and magnetism
• Key formulae — Electromagnetism
• Key formulae — Special relativity