1905 — The Miracle Year · Albert Einstein

The lean years that came first

Einstein at his desk around the time he worked at the Swiss Federal Patent Office in Bern — Einstein in Bern, around 1905. He called the patent office his "worldly cloister" — steady work that left his mind free.Image: Lucien Chavan. Public domain, via Wikimedia Commons (Source)

Graduating in 1900 did not open doors. Einstein's professors found him impudent, and for two years he scraped by on tutoring and temporary teaching. In 1902, his classmate Marcel Grossmann's father recommended him for a post at the Swiss Federal Patent Office in Bern, where he became a "technical expert, third class," assessing inventions — many of them electromechanical.

It suited him perfectly. The work was interesting but undemanding, leaving hours for thinking. In 1903 he married Mileva Marić; their son Hans Albert was born in 1904. With friends he formed the half-joking "Olympia Academy", reading Poincaré, Hume and Mach late into the night.

Sources:

Wikipedia: Annus Mirabilis papers.
Wikipedia: Albert Einstein — "Patent office".

Four papers, one year

The 1905 papers

All four appeared in the Annalen der Physik. Here they are in the order he wrote them.

March — Light quanta & the photoelectric effect

Light, Einstein proposed, comes in discrete packets of energy (later called photons), each carrying energy E = hf. This "very revolutionary" idea explained the photoelectric effect — and, sixteen years later, won him the Nobel Prize. It also helped launch quantum theory.

May — Brownian motion

By explaining the jittering of tiny particles suspended in water as the result of collisions with invisible molecules, Einstein gave direct evidence that atoms and molecules are real — still doubted by some scientists in 1905. Jean Perrin's experiments soon confirmed it.

June — Special relativity

"On the Electrodynamics of Moving Bodies" demolished the idea of absolute time and space. From two simple postulates, Einstein derived that moving clocks run slow and moving objects contract. We give it a whole chapter.

September — Mass–energy equivalence

A three-page afterthought to the relativity paper asked whether a body's mass depends on its energy. The answer became the most famous equation on Earth: E = mc². Explore it here.

Each of the four articles carries its date of receipt in the Annalen der Physik itself. The calendar lays them out across 1905 together with the dissertation — and shows how old Einstein was on each of those days.

The year 1905, day by day

Pick a paper: tap its row in the calendar.

Dated / finished
Submitted in Zurich
Received by the Annalen
Published
14 March: Einstein's 26th birthday

1 Light quanta

„Über einen die Erzeugung und Verwandlung des Lichtes betreffenden heuristischen Gesichtspunkt“

Translation: On a Heuristic Point of View Concerning the Production and Transformation of Light

Annalen der Physik 17, S. 132–148

Dated / finished: 17 March 1905 Einstein was 26 years and 3 days old.
Received by the Annalen: 18 March 1905 Einstein was 26 years and 4 days old.
Published: 9 June 1905 Einstein was 26 years and 87 days old.

What it changed: Light comes in packets of energy, light quanta — this explained the photoelectric effect, helped found quantum theory and won him the Nobel Prize.

Where the sources differ: German Wikipedia gives 17 March: that is the date at the end of the manuscript (“Bern, den 17. März 1905”). According to the journal it was received on 18 March.