Albert Einstein (March 14, 1879 – April 18, 1955) was a German-born
Jewish theoretical physicist of profound genius, who is widely regarded
as the greatest scientist of the 20th century and one of the greatest
scientists of all time. The undisputed "father of modern physics," he
proposed the theory of relativity and also made major contributions
to the development of quantum mechanics, statistical mechanics, and
cosmology. He was awarded the 1921 Nobel Prize for Physics for his
explanation of the photoelectric effect in 1905 (his "miracle
year") and "for his services to Theoretical Physics."
After his general theory of relativity was formulated in November
1915, Einstein became world famous, an unusual achievement for a scientist.
In his later years, his fame exceeded that of any other scientist in
history. In popular culture, his name has become synonymous with great
intelligence and even genius.
Einstein himself was deeply concerned with the social impact of scientific
discovery. His reverence for all creation, his belief in the grandeur,
beauty, and sublimity of the universe (the primary source of inspiration
in science), his awe for the scheme that is manifested in the material
universe—all of these show through in his work and philosophy.
Youth and college
Einstein was born at Ulm in Baden-Württemberg, Germany, about
100 km east of Stuttgart. His parents were Hermann Einstein, a featherbed
salesman who later ran an electrochemical works, and Pauline, whose
maiden name was Koch. They were married in Stuttgart-Bad Cannstatt.
The family was Jewish (non-observant); Albert attended a Catholic elementary
school and, at the insistence of his mother, was given violin lessons.
At age five, his father showed him a pocket compass, and Einstein
realized that something in "empty" space acted upon the needle;
he would later describe the experience as one of the most revelatory
of his life. Though he built models and mechanical devices for fun,
he was considered a slow learner, possibly due to dyslexia, simple
shyness, or the significantly rare and unusual structure of his brain
(examined after his death). He later credited his development of the
theory of relativity to this slowness, saying that by pondering space
and time later than most children, he was able to apply a more developed
intellect. Another, more recent, theory about his mental development
is that he had Asperger's syndrome, a condition related to autism.
Einstein attended the Luitpold Gymnasium where he received a relatively
progressive education. He began to learn mathematics around age twelve.
There is a recurring rumor that he failed mathematics later in his
education, but this is untrue; a change in the way grades were assigned
caused confusion years later. Two of his uncles fostered his intellectual
interests during his late childhood and early adolescence by suggesting
and providing books on science, mathematics and philosophy.
In 1894, following the failure of Hermann's electrochemical business,
the Einsteins moved from Munich to Pavia, Italy (near Milan). During
this year, Einstein's first scientific work was written (called "The
Investigation of the State of Aether in Magnetic Fields"). Albert
remained behind in Munich lodgings to finish school, completing only
one term before leaving the gymnasium in spring 1895 to rejoin his
family in Pavia. He quit without telling his parents and a year and
a half prior to final examinations, Einstein convinced the school to
let him go with a medical note from a friendly doctor, but this meant
he had no secondary-school certificate.
Despite excelling in the mathematics and science portion, his failure
of the liberal arts portion of the Eidgenössische Technische Hochschule
(ETH, Swiss Federal Institute of Technology, in Zurich) entrance exam
the following year was a setback; his family sent him to Aarau, Switzerland,
to finish secondary school, where he received his diploma in September
1896. During this time he lodged with Professor Jost Winteler's family
and became enamoured with Marie, their daughter, his first sweetheart.
Albert's sister Maja was to later marry their son Paul, and his friend
Michele Besso married their other daughter Anna. Einstein subsequently
enrolled at the Eidgenössische Technische Hochschule in October
and moved to Zurich, while Marie moved to Olsberg for a teaching post.
The same year, he renounced his Württemberg citizenship and became
In the spring of 1896, the Serbian Mileva Maric (an acquaintance of
Nikola Tesla) started initially as a medical student at the University
of Zurich, but after a term switched to the same section as Einstein
as the only woman that year to study for the same diploma. Einstein's
relationship with Mileva developed into romance over the next few years.
In 1900, he was granted a teaching diploma by the Eidgenössische
Technische Hochschule (ETH Zurich) and was accepted as a Swiss citizen
in 1901. He kept his Swiss passport for his whole life. During this
time Einstein discussed his scientific interests with a group of close
friends, including Mileva. He and Mileva had an illegitimate daughter
Lieserl, born in January 1902.
Work and doctorate
Upon graduation, Einstein could not find a teaching post, mostly
because his brashness as a young man had apparently irritated most of
The father of a classmate helped him obtain employment as a technical
assistant examiner at the Swiss Patent Office  in 1902. There, Einstein
judged the worth of inventors' patent applications for devices that required
a knowledge of physics to understand. He also learned how to discern
the essence of applications despite sometimes poor descriptions, and
was taught by the director how "to express myself correctly".
He occasionally rectified their design errors while evaluating the practicality
of their work.
Einstein married Mileva Maric on January 6, 1903. Einstein's marriage
to Maric, who was a mathematician, was both a personal and intellectual
partnership: Einstein referred to Mileva as "a creature who is
my equal and who is as strong and independent as I am". Ronald
W. Clark, a biographer of Einstein, claimed that Einstein depended
on the distance that existed in his and Mileva's marriage in order
to have the solitude necessary to accomplish his work; he required
intellectual isolation. Abram Joffe, a Soviet physicist who knew Einstein,
in an obituary of Einstein, wrote, "The author of [the papers
of 1905] was ... a bureaucrat at the Patent Office in Bern, Einstein-Maric" and
this has recently been taken as evidence of a collaborative relationship.
However, according to Alberto A. Martínez of the Center for
Einstein Studies at Boston University, Joffe only ascribed authorship
to Einstein, as he believed that it was a Swiss custom at the time
to append the spouse's last name to the husband's name. Whatever
the truth, the extent of her influence on Einstein's work is a highly
controversial and debated question.
On May 14, 1904, the couple's first son, Hans Albert Einstein, was
born. In 1904, Einstein's position at the Swiss Patent Office was made
permanent. He obtained his doctorate after submitting his thesis "A
new determination of molecular dimensions" ("Eine neue Bestimmung
der Moleküldimensionen") in 1905.
That same year, he wrote four articles that provided the foundation
of modern physics, without much scientific literature to which he could
refer or many scientific colleagues with whom he could discuss the
theories. Most physicists agree that three of those papers (on Brownian
motion, the photoelectric effect, and special relativity) deserved
Nobel Prizes. Only the paper on the photoelectric effect would win
one. This is ironic, not only because Einstein is far better-known
for relativity, but also because the photoelectric effect is a quantum
phenomenon, and Einstein became somewhat disenchanted with the path
quantum theory would take. What makes these papers remarkable is that,
in each case, Einstein boldly took an idea from theoretical physics
to its logical consequences and managed to explain experimental results
that had baffled scientists for decades.
Annus Mirabilis Papers
Einstein submitted the series of papers to the "Annalen der Physik".
They are commonly referred to as the "Annus Mirabilis Papers" (from
Annus mirabilis, Latin for 'year of wonders'). The International Union
of Pure and Applied Physics (IUPAP) plans to commemorate the 100th
year of the publication of Einstein's extensive work in 1905 as the
'World Year of Physics 2005'.
The first paper, named "On a Heuristic Viewpoint Concerning the
Production and Transformation of Light", ("Über einen
die Erzeugung und Verwandlung des Lichtes betreffenden heuristischen
Gesichtspunkt") proposed the idea of "energy quanta" (which
underlies the concept of what are now called photons) and showed how
it could be used to explain such phenomena as the photoelectric effect.
This paper was specifically cited for his Nobel Prize.
His second article in 1905, named "On the Motion—Required
by the Molecular Kinetic Theory of Heat—of Small Particles Suspended
in a Stationary Liquid", ("Über die von der molekularkinetischen
Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten
suspendierten Teilchen") covered his study of Brownian motion,
and provided empirical evidence for the existence of atoms.
Einstein's third paper that year, "On the Electrodynamics of
Moving Bodies" ("Zur Elektrodynamik bewegter Körper"),
was published on June 30, 1905. While developing this paper, Einstein
wrote to Mileva about "our work on relative motion", and
this has led some to ask whether Mileva played a part in its development.
This paper introduced the special theory of relativity, a theory of
time, distance, mass and energy which was consistent with electromagnetism,
but omitted the force of gravity.
A fourth paper, "Does the Inertia of a Body Depend Upon Its Energy
Content?", ("Ist die Trägheit eines Körpers von
seinem Energieinhalt abhängig?") published late in 1905,
showed one further deduction from relativity's axioms, the famous equation
that the energy of a body at rest (E) equals its mass (m) times the
speed of light (c) squared.
In 1906, Einstein was promoted to technical examiner second class.
In 1908, Einstein was licensed in Bern, Switzerland, as a Privatdozent
(unsalaried teacher at a university). Einstein's second son, Eduard,
was born on July 28, 1910. In 1911, Einstein became first associate
professor at the University of Zurich, and shortly afterwards full
professor at the (German) University of Prague, only to return the
following year to Zurich in order to become full professor at the ETH
Zurich. At that time, he worked closely with the mathematician Marcel
Grossmann. In 1912, Einstein started to refer to time as the fourth
In 1914, just before the start of World War I, Einstein settled in
Berlin as professor at the local university and became a member of
the Prussian Academy of Sciences. He took German citizenship. His pacifism
and Jewish origins irritated German nationalists. After he became world-famous,
nationalistic hatred of him grew and for the first time he was the
subject of an organized campaign to discredit his theories. From 1914
to 1933, he served as director of the Kaiser Wilhelm Institute for
Physics in Berlin, and it was during this time that he was awarded
his Nobel Prize and made his most groundbreaking discoveries. He was
also an extraordinary professor at the Leiden University from 1920
till officially 1946, where he regularly gave guest lectures.
Einstein divorced Mileva on February 14, 1919, and married his cousin
Elsa Löwenthal (born Einstein: Löwenthal was the surname
of her first husband, Max) on June 2, 1919. Elsa was Albert's first
cousin (maternally) and his second cousin (paternally). She was three
years older than Albert, and had nursed him to health after he had
suffered a partial nervous breakdown combined with a severe stomach
ailment; there were no children from this marriage. The fate of Albert
and Mileva's first child, Lieserl, is unknown. Some believe she died
in infancy, while others believe she was given out for adoption. They
later had two sons: Eduard and Hans Albert. Eduard intended to practice
as a Freudian analyst but was institutionalized for schizophrenia and
died in an asylum. Hans Albert, his older brother, became a professor
of hydraulic engineering at the University of California, Berkeley,
having little interaction with his father.
In November 1915, Einstein presented a series of lectures before the
Prussian Academy of Sciences in which he described his theory of general
relativity. The final lecture climaxed with his introduction of an
equation that replaced Newton's law of gravity. This theory considered
all observers to be equivalent, not only those moving at a uniform
speed. In general relativity, gravity is no longer a force (as it is
in Newton's law of gravity) but is a consequence of the curvature of
The theory provided the foundation for the study of cosmology and
gave scientists the tools for understanding many features of the universe
that were discovered well after Einstein's death. A truly revolutionary
theory, general relativity has so far passed every test posed to it
and has become a powerful tool used in the analysis of many subjects
Initially, scientists were skeptical because the theory was derived
by mathematical reasoning and rational analysis, not by experiment
or observation. But in 1919, predictions made using the theory were
confirmed by Arthur Eddington's measurements (during a solar eclipse),
of how much the light emanating from a star was bent by the Sun's gravity
when it passed close to the Sun, an effect called gravitational lensing.
On November 7, The Times reported the confirmation, cementing Einstein's
Many scientists were still unconvinced for various reasons ranging
from disagreement with Einstein's interpretation of the experiments,
to not being able to tolerate the absence of an absolute frame of reference.
In Einstein's view, many of them simply could not understand the mathematics
involved. Einstein's public fame which followed the 1919 article created
resentment among these scientists some of which lasted well into the
In the early 1920s Einstein was the lead figure in a famous weekly
physics colloquium at the University of Berlin. On March 30, 1921,
Einstein went to New York to give a lecture on his new Theory of Relativity,
the same year he was awarded the Nobel Prize. Though he is now most
famous for his work on relativity, it was for his earlier work on the
photoelectric effect that he was given the Prize, as his work on general
relativity was still disputed. The Nobel committee decided that citing
his less-contested theory in the Prize would gain more acceptance from
the scientific community.
The "Copenhagen" interpretation
Einstein's relationship with quantum physics was quite remarkable.
He was the first to say that quantum theory was revolutionary. His
postulation that light can be described not only as a wave with no
kinetic energy, but also as massless discrete packets of energy called
quanta with measurable kinetic energy (now known as photons) marked
a landmark break with the classical physics. In 1909 Einstein presented
his first paper on the quantification of light to a gathering of physicists
and told them that they must find some way to understand waves and
In the mid-1920s, as the original quantum theory was replaced with
a new theory of quantum mechanics, Einstein balked at the Copenhagen
interpretation of the new equations because it settled for a probabilistic,
non-visualizable account of physical behaviour. Einstein agreed that
the theory was the best available, but he looked for a more "complete" explanation,
i.e., more deterministic. He could not abandon the belief that physics
described the laws that govern "real things", the belief
which had led to his successes with atoms, photons, and gravity.
In a 1926 letter to Max Born, Einstein made a remark that is now famous:
Quantum mechanics is certainly imposing. But an inner voice tells
me it is not yet the real thing. The theory says a lot, but does not
really bring us any closer to the secret of the Old One. I, at any
rate, am convinced that He does not throw dice.
To this, Bohr, who sparred with Einstein on quantum theory, retorted, "Stop
telling God what He must do!" The Bohr-Einstein debates on foundational
aspects of quantum mechanics happened during the Solvay conferences.
Einstein was not rejecting probabilistic theories per se. Einstein
himself was a great statistician, using statistical analysis in his
works on Brownian motion and photoelectricity and in papers published
before the miraculous year 1905; Einstein had even discovered Gibbs
ensembles. However, he believed that, at the core, physical reality
behaved deterministically. Many physicists argue that experimental
evidence contradicting this belief was found much later with the discovery
of Bell's Theorem and Bell's inequality. However, there is still space
for lively discussions about the interpretation of quantum mechanics.
In 1924, Einstein received a short paper from a young Indian physicist
named Satyendra Nath Bose describing light as a gas of photons and
asking for Einstein's assistance in publication. Einstein realized
that the same statistics could be applied to atoms, and published an
article in German (then the lingua franca of physics) which described
Bose's model and explained its implications. Bose-Einstein statistics
now describe any assembly of these indistinguishable particles known
as bosons. The Bose-Einstein condensate phenomenon was predicted in
the 1920s by Bose and Einstein, based on Bose's work on the statistical
mechanics of photons, which was then formalized and generalized by
Einstein. The first such condensate was produced by Eric Cornell and
Carl Wieman in 1995 at the University of Colorado at Boulder. Einstein's
original sketches on this theory were recovered in August 2005 in the
library of Leiden University (see website with original manuscript:
Einstein also assisted Erwin Schrödinger in the development of
the quantum Boltzmann distribution, a mixed classical and quantum mechanical
gas model although he realized that this was less significant than
the Bose-Einstein model and declined to have his name included on the
The Einstein refrigerator
Einstein and Szilárd's refrigerator patent diagram.Einstein
and former student Leó Szilárd co-invented a unique type
of refrigerator (usually called the Einstein refrigerator) in 1926.
On November 11, 1930, U.S. Patent 1,781,541 was awarded to
Albert Einstein and Leó Szilárd. The patent covered a
thermodynamic refrigeration cycle providing cooling with no moving
parts, at a constant pressure, with only heat as an input. The refrigeration
cycle used ammonia, butane, and water.
World War II
After Adolf Hitler came to power in 1933, expressions of hatred for
Einstein reached new levels. He was accused by the National Socialist
regime of creating "Jewish physics" in contrast with Deutsche
Physik—"German" or "Aryan physics". Nazi
physicists (notably including the Nobel laureates Johannes Stark
and Philipp Lenard) continued the attempts to discredit his theories
and to blacklist politically those German physicists who taught them
(such as Werner Heisenberg). Einstein renounced his German citizenship
and fled to the United States, where he was given permanent residency.
He accepted a position at the newly founded Institute for Advanced
Study in Princeton Township, New Jersey. He became an American citizen
in 1940, though he still retained Swiss citizenship.
In 1939, under the encouragement of Szilárd, Einstein sent
a letter to President Franklin Delano Roosevelt urging the study of
nuclear fission for military purposes, under fears that the Nazi government
would be first to develop atomic weapons. Roosevelt started a small
investigation into the matter which eventually became the massive Manhattan
Institute for Advanced Study
His work at the Institute for Advanced Study focused on the unification
of the laws of physics, which he referred to as the Unified Field Theory.
He attempted to construct a model which would describe all of the fundamental
forces as different manifestations of a single force. His attempt was
hindered because the strong and weak nuclear forces were not understood
independently until around 1970, fifteen years after Einstein's death.
Einstein's goal of unifying the laws of physics under a single model
survives in the current drive for unification of the forces, embodied
most notably by string theory.
Einstein began to form a generalized theory of gravitation with the
Universal Law of Gravitation and the electromagnetic force in his first
attempt to demonstrate the unification and simplification of the fundamental
forces. In 1950 he described his work in a Scientific American article.
Einstein was guided by a belief in a single statistical measure of
variance for the entire set of physical laws.
Einstein's Generalized Theory of Gravitation is a universal mathematical
approach to field theory. He investigated reducing the different phenomena
by the process of logic to something already known or evident. Einstein
tried to unify gravity and electromagnetism in a way that also led
to a new subtle understanding of quantum mechanics.
Einstein postulated a four-dimensional space-time continuum expressed
in axioms represented by five component vectors. Particles appear in
his research as a limited region in space in which the field strength
or the energy density are particularly high. Einstein treated subatomic
particles as objects embedded in the unified field, influencing it
and existing as an essential constituent of the unified field but not
of it. Einstein also investigated a natural generalization of symmetrical
tensor fields, treating the combination of two parts of the field as
being a natural procedure of the total field and not the symmetrical
and antisymmetrical parts separately. He researched a way to delineate
the equations and systems to be derived from a variational principle.
Einstein became increasingly isolated in his research on a generalized
theory of gravitation and was ultimately unsuccessful in his attempts.
In 1948, Einstein served on the original committee which resulted in
the founding of Brandeis University. A portrait of Einstein was taken
by Yousuf Karsh on February 11 of that same year. In 1952, the Israeli
government proposed to Einstein that he take the post of second president.
He declined the offer, and remains the only United States citizen ever
to be offered a position as a foreign head of state. On March 30, 1953,
Einstein released a revised unified field theory.
He died at a hospital in Princeton, New Jersey, on April 18, 1955,
leaving the Generalized Theory of Gravitation unsolved. The only person
present at his deathbed, a hospital nurse, said that just before his
death he mumbled several words in German that she did not understand.
He was cremated without ceremony on the same day he died at Trenton,
New Jersey, in accordance with his wishes. His ashes were scattered
at an undisclosed location.
His brain was preserved by Dr. Thomas Stoltz Harvey, the pathologist
who performed the autopsy on Einstein. Harvey found nothing unusual
with his brain, but in 1999 further analysis by a team at McMaster
University revealed that his parietal operculum region was missing
and, to compensate, his inferior parietal lobe was 15% wider than normal
. The inferior parietal region is responsible for mathematical thought,
visuospatial cognition, and imagery of movement. Einstein's brain also
contained 73% more glial cells than the average brain.
Albert Einstein was much respected for his kind and friendly demeanor
rooted in his pacifism. He was modest about his abilities, and had
distinctive attitudes and fashions—for example, he minimized
his wardrobe so that he would not need to waste time in deciding on
what to wear. He occasionally had a playful sense of humor, and enjoyed
sailing and playing the violin. He was also the stereotypical "absent-minded
professor"; he was often forgetful of everyday items, such as
keys, and would focus so intently on solving physics problems that
he would often become oblivious to his surroundings.
Although he was raised Jewish, he was not a believer in Judaism. He
simply admired the beauty of nature and the universe. From a letter
written in English, dated March 24, 1954, Einstein wrote, "It
was, of course, a lie what you read about my religious convictions,
a lie which is being systematically repeated. I do not believe in a
personal God and I have never denied this but have expressed it clearly.
If something is in me which can be called religious then it is the
unbounded admiration for the structure of the world so far as our science
can reveal it."
He also said (in an essay reprinted in Living Philosophies, vol. 13
(1931)): "A knowledge of the existence of something we cannot
penetrate, our perceptions of the profoundest reason and the most radiant
beauty, which only in their most primitive forms are accessible to
our minds - it is this knowledge and this emotion that constitute true
religiosity; in this sense, and this [sense] alone, I am a deeply religious
The following is a response made to Rabbi Herbert Goldstein of the
International Synagogue in New York which read, "I believe in
Spinoza's God who reveals himself in the orderly harmony of what exists,
not in a God who concerns himself with the fates and actions of human
beings." After being pressed on his religious views by Martin
Buber, Einstein exclaimed, "What we [physicists] strive for is
just to draw His lines after Him." Summarizing his religious beliefs,
he once said: "My religion consists of a humble admiration of
the illimitable superior spirit who reveals himself in the slight details
we are able to perceive with our frail and feeble mind."
He also expressed admiration for Buddhism, which he said "has
the characteristics of what would be expected in a cosmic religion
for the future: It transcends a personal God, avoids dogmas and theology;
it covers both the natural and the spiritual, and it is based on a
religious sense aspiring from the experience of all things, natural
and spiritual, as a meaningful unity."
Victor J. Stenger, author of Has Science Found God? (2001), wrote
of Einstein's presumed pantheism, "Both deism and traditional
Judeo-Christian-Islamic theism must also be contrasted with pantheism,
the notion attributed to Baruch Spinoza that the deity is associated
with the order of nature or the universe itself. This also crudely
summarizes the Hindu view and that of many indigenous religions around
the world. When modern scientists such as Einstein and Stephen Hawking
mention 'God' in their writings, this is what they seem to mean: that
God is Nature."
Einstein was an Honorary Associate of the Rationalist Press Association
Einstein considered himself a pacifist and humanitarian, and
in later years, a committed democratic socialist. He once said, "I
believe Gandhi's views were the most enlightened of all the political
men of our time. We should strive to do things in his spirit: not to
use violence for fighting for our cause, but by non-participation of
anything you believe is evil." Einstein's views on other issues,
including socialism, McCarthyism and racism, were controversial (see
Einstein on socialism). Einstein was a co-founder of the liberal German
The U.S. FBI kept a 1,427 page file on his activities and recommended
that he be barred from immigrating to the United States under the Alien
Exclusion Act, alleging that Einstein "believes in, advises, advocates,
or teaches a doctrine which, in a legal sense, as held by the courts
in other cases, 'would allow anarchy to stalk in unmolested' and result
in 'government in name only'", among other charges. They also
alleged that Einstein "was a member, sponsor, or affiliated with
thirty-four communist fronts between 1937-1954" and "also
served as honorary chairman for three communist organizations." It
should be noted that many of these documents were submitted to the
FBI, mainly by civilian political groups, and not actually written
by FBI officials.
Einstein opposed tyrannical forms of government, and for this reason
(and his Jewish background), opposed the Nazi regime and fled Germany
shortly after it came to power. He initially favored construction of
the atomic bomb, in order to ensure that Hitler did not do so first,
and even sent a letter to President Roosevelt (dated August 2,
1939, before World War II broke out, and likely authored by Leó Szilárd)
encouraging him to initiate a program to create a nuclear weapon. Roosevelt
responded to this by setting up a committee for the investigation of
using uranium as a weapon, which in a few years was superseded by the
After the war, though, Einstein lobbied for nuclear disarmament and
a world government: "I know not with what weapons World War III
will be fought, but World War IV will be fought with sticks and stones."
Einstein was a supporter of Zionism. He supported Jewish settlement
of the ancient seat of Judaism and was active in the establishment
of the Hebrew University in Jerusalem, which published (1930) a volume
titled About Zionism: Speeches and Lectures by Professor Albert Einstein,
and to which Einstein bequeathed his papers. However, he opposed nationalism
and expressed skepticism about whether a Jewish nation-state was the
best solution. He may have imagined Jews and Arabs living peacefully
in the same land. In later life, in 1952, he was offered the post of
second president of the newly created state of Israel, but declined
the offer, claiming that he lacked the necessary people skills.
Einstein, along with Albert Schweitzer and Bertrand Russell, fought
against nuclear tests and bombs. As his last public act, and just days
before his death, he signed the Russell-Einstein Manifesto, which led
to the Pugwash Conferences on Science and World Affairs. His letter
to Russell read:
Dear Bertrand Russell,
Thank you for your letter of April 5. I am gladly willing to sign your
excellent statement. I also agree with your choice of the prospective
With kind regards, A. Einstein