Albert Einstein

Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist whose work transformed modern science. Best known for developing the theory of relativity, he also made foundational contributions to quantum mechanics, statistical physics and cosmology. His equation expressing mass–energy equivalence, E = mc², became one of the most recognised scientific formulas in history. In 1921 he received the Nobel Prize in Physics for his explanation of the photoelectric effect, a cornerstone of quantum theory. Einstein’s life and career spanned the German Empire, Switzerland, Weimar Germany and the United States, reflecting the turbulent political and intellectual landscape of the early twentieth century.

Early Life and Education

Einstein was born in Ulm in the Kingdom of Württemberg, then part of the German Empire. His secular Jewish parents, Hermann Einstein and Pauline Koch, soon moved the family to Munich, where Hermann and his brother Jakob ran an electrical engineering firm. Einstein’s fascination with science began early: he later recalled being captivated by a magnetic compass his father showed him when he was ill, sensing that “something deeply hidden” governed the universe.
He attended St Peter’s Catholic school and later the Luitpold Gymnasium, but he struggled with the school’s strict pedagogical methods. At fifteen he left Germany to join his family in Italy, renouncing his Württemberg citizenship in 1896 to avoid military conscription. After completing his secondary education at the Cantonal School in Aarau, Switzerland, he enrolled in the mathematics and physics teaching diploma programme at the Swiss Federal Polytechnic (ETH Zurich). There he formed a close intellectual partnership with fellow student Mileva Marić, who later became his first wife.

Early Career and Annus Mirabilis

Einstein obtained Swiss citizenship in 1901 and began working at the Swiss Patent Office in Bern. In 1905, his celebrated annus mirabilis (miracle year), he produced four papers that reshaped physics:

• A study of the photoelectric effect, providing evidence for the particle nature of light
• A quantitative explanation of Brownian motion
• The formulation of the special theory of relativity
• The demonstration of mass–energy equivalence

He earned his doctorate from the University of Zurich that same year. These works established him as a major figure in theoretical physics.

General Relativity and Scientific Ascendancy

Einstein accepted academic posts in Zurich and Prague before moving to Berlin in 1914 to join the Prussian Academy of Sciences. There he developed general relativity, published in 1915, which reconceptualised gravitation as the curvature of spacetime produced by mass and energy. Subsequent work in 1916 extended the theory to cosmology, providing new models of the universe’s structure and evolution.
In 1917 he introduced the concepts of spontaneous and stimulated emission—principles central to the later development of lasers and masers. He continued to contribute to quantum theory, particularly radiation physics, often collaborating with scientists such as Satyendra Nath Bose. Together they laid the foundation for Bose–Einstein statistics.

Political Upheaval and Emigration

Einstein’s life was shaped by political change. Though originally a Württemberg subject, he lived in Switzerland from 1895 and held Swiss citizenship for the rest of his life. He became a Prussian citizen in 1914 and remained in Berlin until 1933. During a trip to the United States that year, Adolf Hitler came to power in Germany. As a prominent Jew and critic of German militarism, Einstein refused to return. He settled in the United States, accepting a position at the Institute for Advanced Study in Princeton, and became an American citizen in 1940.
Concerned by reports of German atomic research, Einstein co-signed the Einstein–Szilárd letter urging President Franklin D. Roosevelt to support nuclear research in the United States, which contributed to the launch of the Manhattan Project.

Later Work and Intellectual Commitments

From the 1920s onward Einstein sought a unified field theory to reconcile gravitation and electromagnetism within a geometric framework. His rejection of the probabilistic nature of quantum mechanics—famously expressed in his remark that “God does not play dice”—led to disagreements with other physicists and growing isolation from mainstream theoretical developments.
Nevertheless, his contributions to quantum theory, statistical mechanics and the physics of radiation remained influential. He continued to publish, lecture and engage in scientific debate throughout his career.

Moral, Political and Social Engagement

Einstein’s moral commitments extended beyond science. He advocated pacifism, civil liberties and international cooperation. After the Second World War he participated in campaigns against nuclear weapons and supported world federalist movements. A committed anti-racist, he publicly opposed segregation in the United States and supported civil rights initiatives. His views were shaped by personal experience of nationalism, authoritarianism and antisemitism.

Personal Life

Einstein married Mileva Marić in 1903, and the couple had two sons; they divorced in 1919. Later that year he married his cousin Elsa Löwenthal. Einstein maintained a complex personal life, marked by numerous extramarital relationships, extensive correspondence and close intellectual friendships. His sister Maja, to whom he remained devoted, lived with him in his later years.

Death and Legacy

Einstein died on 18 April 1955 in Princeton, New Jersey. His intellectual legacy is vast: the theories of special and general relativity underpin modern physics, astrophysics and cosmology, while his work on light quanta helped shape quantum mechanics. His name became synonymous with scientific genius and his writings on peace, ethics and human dignity continue to influence global thought.