Albert Einstein

Theoretical physicist — Albert Einstein (Ulm 1879 – Princeton 1955) was a German-born theoretical physicist, later stateless, Swiss, and finally American, of Jewish origin. In 1905, his “miracle year” while working at the patent office in Bern, he published four revolutionary papers on Brownian motion, the photoelectric effect, special relativity and mass-energy equivalence. Special relativity redefined the concepts of space and time by unifying them, while in 1915 general relativity reinterpreted gravity as the curvature of spacetime, replacing the Newtonian view. His work on the photoelectric effect contributed to the birth of quantum mechanics, though he criticised its probabilistic interpretation. He is considered the most influential physicist of the twentieth century and an icon of scientific thought.

Trivia

He received the Nobel Prize in Physics in 1921 not for relativity, still controversial, but for his explanation of the photoelectric effect; in 1952 he was offered the presidency of the State of Israel, which he declined.

Theories and contributions

• Mass-energy equivalence — Mass and energy are two aspects of the same quantity: $E=mc^2$.
• Special relativity — Physical laws are the same in every inertial frame and the speed of light is constant; from this follows time dilation $\Delta t = \gamma \Delta t_0$.
• General relativity — Gravity is the curvature of spacetime generated by mass and energy: $G_{\mu\nu}=\frac{8\pi G}{c^4}T_{\mu\nu}$.
• Photoelectric effect — Light is quantised into photons of energy $E=h\nu$; explains the emission of electrons from metals.

Present in chapters

05 09 14 16 17 19 20 21 22 Z

Linked atoms

30 linked atoms.

05 Quantità di moto e urti

• Huygens and the laws of collisions

09 Teoria cinetica dei gas

• Atoms: from philosophical hypothesis to experimental evidence

14 Campo elettrico e potenziale

• Is the field a thing or a calculation?
• Why invent the field?

16 Onde

• Newton versus Huygens: waves or particles?

17 Il campo magnetico

• Magnetism is electrostatics plus relativity

19 Le equazioni di Maxwell e le onde elettromagnetiche

• Maxwell’s equations as poetry
• Maxwell and unification: when c emerges from the equations

20 Relatività ristretta

• The paradox of light
• The three hypotheses
• The ether and the Michelson-Morley experiment
• Einstein’s postulates
• The light clock
• The Minkowski plane and the light cone
• E = mc²
• The equivalence principle
• The lift in free fall
• Schwarzschild metric and black holes
• Invariance, the true heart of relativity
• From Galileo to Einstein

21 Introduzione alla meccanica quantistica

• The four great themes of quantum mechanics
• Wave-particle duality
• The historic experiment of the photoelectric effect
• The polarising filter
• Waves, particles and the observer problem

22 La fisica nucleare

• The end of the book
• Nuclear fission

Z Appendice — Maturità

• Advice for the oral exam
• Radioactive decay: nuclear physics, kinetics and relativity
• Photoelectron in a magnetic field: quantum physics and magnetism