Schrodinger
NAME: Schrodinger, Erwin
ACHIEVEMENTS: Wave mechanics. Genetics.
NICKNAME/ALIAS: None
DATE AND PLACE OF BIRTH: August 12, 1887, Vienna, Austria
DATE/PLACE OF DEATH/AGE AT DEATH: January 4, 1961, Vienna, Austria. Aged 73
DISCIPLINE: Physicist
FIELD: Physics
LANGUAGE: German, English
PARENTS: Rudolf Schrodinger; Georgine Bauer
SIBLINGS: None
SPOUSE: Annemarie Bertel
CHILDREN: 2 daughters outside marriage
EDUCATION: At home; high school, Vienna; University of Vienna
MAJOR WORK: Four papers on wave mechanics, "What is Life", "Space, Time, Structure", "Nature and the Greeks"
LIFE AND TIMES:
While on active service in the artillery in the First World War (1914-18), Schrodinger wrote several scientific papers. In 1916, his reading of <a pal of> Einstein's* theory of relativity and <inspired by> Mach*'s experiments on optics inspired him to pursue his career in science.
After the War, he joined the research staff at the Physics Institute in Vienna. He also took an interest in European and Eastern philosophies, including that of <influenced by> Schopenhauer* and the "Upanishads", the sacred texts of the Hindu.
A paper by Einstein on the emission of light as particles (photons) encouraged Schrodinger to experiment on the wave properties of light. In 1919, he published "Theory of Pigments of Maximum Luminosity", in which he introduced the concept of ideal colors, proving that a color mixed from pigments having the characteristics of ideal colors will have the maximum brightness obtainable for that color. The paper was a breakthrough in color theory and the concept of ideal colors has remained useful in color analysis.
By the early 1920s, Schrodinger was recognized as the world authority on color theory. In 1921, he was appointed Professor of Physics at Zurich University, in Switzerland. In 1925, while preparing lectures on quantum statistics, Schrodinger read Einstein's paper on gas statistics, which alerted him to the doctoral thesis of the French scientist <influenced by> De Broglie*.
Einstein had accepted De Broglie's view that matter had a dual nature and that particles of matter sometimes acted like waves. Schrodinger began to think about these waves and what laws and equations they were obeying. In six months, he had worked out his theory of wave mechanics.
Using his partial differential equation, called "the wave equation", Schrodinger explained how matter could behave like waves. The solutions to his equations are wave functions that can be postulated only for a probable scenario, not for a definite sequence of events, meaning the scientist has to include the probability factor in any calculations.
In 1927, Schrodinger gave a series of lectures at the University of Wisconsin and on his return to Europe was invited to take the chair of physics at Berlin University. At Berlin, he joined a weekly gathering of colleagues who discussed new theories and discoveries. Among the participants were <a pal of> Planck*, <a pal of> Nernst* and Einstein, with whom he became good friends.
In 1933, Schrodinger's opposition to Nazism led him to leave Germany and through British scientist, <helped by> Lindemann*, he obtained a post at Oxford University. Soon after his arrival, he was awarded the Nobel prize for physics (shared with <shared Nobel with> Dirac*) for their separate work on atomic theory. Over the next seven years, Schrodinger lived at different times in Austria, Britain, Belgium, and Rome, before settling at the Dublin Institute for Advanced Studies, one of whose founders was <invited to Ireland by> de Valera*, the Irish premier. He stayed in Ireland 15 years, doing research in physics, philosophy and the history of science.
In 1943, Schrodinger gave three public lectures at Oxford under the title "What is Life?", in which he attempted to use quantum physics to explain the stability of genetic structure. He suggested that the most essential part of the living cell, the chromosome, was a genetic code. He described the gene as "the hypothetical material carrier of a definite hereditary feature".
In earlier publications others had mentioned the idea of a code in the chromosomes, but Schrodinger was the first to state it clearly in physical terms. He described the chromosome fiber as a "linear code for the information that constitutes the genotype of a particular individual organism".
The lectures were published in book form in 1944 and were translated into seven languages. Schrodinger's theory had a profound influence on both physicists and biologists and stimulated the development of molecular biology. <influenced> Watson* (who, with <influenced> Crick*, later cracked the genetic DNA code) read it as a student in 1956 and was inspired by it.
Schrodinger gave a series of lectures, "Nature and the Greeks", in 1954 before he retired from his post in Dublin and returned to Vienna in 1956, where he was made Professor Emeritus at the university. His last book, "My View of the World" (1961), was influenced by East Indian sacred texts.
ASSESSMENT: Best known for his discovery of wave mechanics, for which he was awarded the Nobel prize
EXTRA CONNECTIONS: Was a contemporary of <a colleague of> Pauli* at Zurich.
His work related to that of <work related to> Heisenberg* and <work related to> Born*
He influenced the work of <influenced> Neumann*
ONELINER: Erwin Schrodinger, quantum physics Nobel
BIBLIOGRAPHY:
Moore, Walter, A Life of Erwin Schrodinger, Cambridge University Press, 1994
SchroSERWIN SCHRODINGER:
Erwin Schrodinger born in 1887 in Vienna, Austria. Only child who was taught
at home til aged 11 by both private tutor and his father, Rudolph
Schrodinger, who was an industrial chemist (owner of oilcloth factory) and
talented amateur painter and botanist. In 1898 he entered the Akademische
Gymnasium in Vienna to complete pre-college studies, and then entered
University of Vienna in 1906, from where received his Ph.D. in 1910. While
at Vienna, Schrodinger was v. influenced by Fritz Hasenohrl, brilliant young
professor of theoretical physics, who was killed a decade later during WWI.
In 1910, Schrodinger became assistant to experimental physicist Franz Exner
at Univer of Vienna's Second Physics Institute, where studied magnetism and
dielectrics. In 1913 he and K.W.F. Kohlrausch won the Haitinger Prize of the
Imperial Academy of Sciences for thier experimental work with radium. During
WWI, Sch. served as artillery officer assigned to Italian front: fortunately
stationed in remote mountain areas - used much free time to study Einstein's
general theory of relativity. After end of war, he returned to Second
Physics Institute; married Annemarie Bertel (1920 - had no children) and
conducted research on general relativity, statistical mechanics (study of
systems with very large number of interacting objects, such as molecules of
a gas), and X ray diffraction. Also did extensive exp. and theoretical
research on theory of colours and how they are perceived - particularly,
relationship between red-green and blue-yellow colour blindness.
In 1920, Schrodinger went to Germany as assistant to Max Wien at Univ. of
Jena, but after 4 months accepted position as assistant prof at the
Technische Hochschule in Stuttgart. Left there after only one term, to
become briefly as assist. professor at Breslau (now Wroclaw, Poland), then
shortly afterwards (late 1921) moving to Switzerland to take position as
full professor of theoretical physics at Univ. of Zurich (following on from
Einstein and Max von Laue). Stayed here for six highly productive years
(1921-27), and during this period investigated primarily thermodynamics and
statistical mechanics, and their application to the understanding of the
nature of gases and solids. His interests included quantum theory, but did
not concentrate on this until 1925, when Einstein praised Louis de Broglie's
wave representation of matter.
Wave mechanics: Schr. was profoundly influenced by de Broglie's work on
waves associated with the motion of free particles (1923-24): in 1924
Broglie had announced his hypothesis of the existence of matter waves -
concept few physicists (Einstein an exception) were ready to accept. In
1925, therefore, Schr. set about trying to apply this concept to bound
particles, to improve on the Bohr model of the atom: specifically, began to
consider the possibility of expressing the movement of an electron in an
atom in terms of a wave. Adopting premise that an electron can travel around
the nucleus only in a standing wave (ie in pattern described by a whole
number of wavelengths), he then looked for a mathematical equation that wd
describe the position of such "permitted" orbits - and by Jan 1926 had
completed first of 4 papers describing results of research. Had found a
second order partial differential equation that specified certain orbitals
(energy levels) outside the nucleus where an electron wave with a whole
number of wavelengths cd be found. These orbitals corresponded precisely to
the orbitals that Niels Bohr had proposed on purely empirical grounds 13 yrs
earlier.
Achievement was that Schr's wave equation i) provided sound theoretical
basis for Bohr's atomic model; ii) allowed calculation of energy changes
that occur when an electron moves from one permitted orbital to a higher or
lower one - with energy changes conforming to those actually observed in
spectroscopic measurements; and iii) explained why electrons cannot exist in
regions between Bohr orbitals, since only non-whole number wavelengths (and,
therefore, non-permitted waves) can exist there. Announced results (which he
arrived at using non-relativistic electron waves in his derivations) in his
early 1926 papers, and equation became known as "the Schrodinger wave
equation" or simply "the wave equation". Wave equation was second
theoretical mechanism proposed for describing electrons in an atom - first
being Werner Heisenberg's matrix mechanics. Most physicists instantly
preferred Schrodinger's, since it lent itself to a physical, rather than
strictly mathematical, interpretation; however, as it turned out, Schr. was
soon able to show that wave mechanics and matrix mechanics are
mathematically identical.
In 1927, Schr. succeeded Max Planck (at Planck's request) as prof. of
theoretical physics at the Univ. of Berlin. Before taking up post, he
visited the U.S. (late 1926-june 1927, pp. 165-8). In Berlin, Schr. became
close friend with Einstein, and attended theatre v. frequently. However, he
resigned post in 1933 in protest at rise to power of Hitler, generally
disgusted by Nazi persecutions and specifically in protest against a street
attack on one of his (Jewish) assistants. Schr. then went to England as
guest professor at Magdalen College, Oxford, where he learned that had been
awarded 1933 Nobel Prize for Physics, shared with Dirac. In 1936, despite
awareness of precarious position of Austria, he accepted position at Univ.
of Graz, but two years later was dismissed from his post, in August 1938,
and he fled the country. While at Graz, Schr. spent much time studying work
of astrophysicist Arthur Eddington, who he had met in Cambridge in 1935-36.,
and during 1936-39 he published only two notable papers, on proper
vibrations of the expanding universe.
LINK WITH DE VALERA:
Schrodinger had first contact with de Valera when he fled Germany in
September 1938 after his dismissal from his post as prof. of theoretical
physics at Univ. of Graz in Austria. Went with his wife first to Rome by
train (cos of Mussolini-Hitler pact cd travel there without visa), where
were met by Enrico Fermi and taken to Papal Academy - here Sch. wrote 3
letters, one of which was addressed to de Valera, then President of the
League of Nations in Geneva. Two days later spoke to de V. on telephone at
the Irish legation, who advised them to travel asap to England, cos was such
a danger of war (just before invasion of Czech) - went via Geneva, where met
de Valera for three days. Arrived in England in October 1938, took up post
for year at Uni. of Ghent in Belgium, before moving to Dublin in October
1939.
Sch. had been offered post of first director of the School of Theoretical
Physics in the Dublin Institute for Advanced Studies, established through
efforts of Eamon de Valera. Schr. remained here for next 17 years,
conducting research on wave mechanics, statistics, statistical
thermodynamics, field theory, and esp. general relativity. Was in Dublin
(where was later joined by Dirac) that Schr. also became concerned with the
philosophical implications of physics, and in particular the possible
application of physics to biology. Proposed a molecular approach to the
study of genes in 'What Is Life? The Physical Aspects of a Living Cell'
(1944), a book which influenced a number of biologists, including Francis
Crick and Maurice H.F. Wilkins. He also published a volume of poetry.
After WWII, Austrian govt tried to persuade Schr. to return to Austria, but
he refused to do so as long as Soviet troops were in occupation. In 1956 he
finally accepted a chair in theoretical physics at Univ. of Vienna, his last
position. He retired in 1958 at age of 71, and died three years later in
Vienna.
In addition to pioneering work in wave mechanics, Schr published research
papers on specific heats of solids, statistical thermodynamics, atomic
spectra, radium, space and time, theory of colour, science and the human
temperament, plus a collection of poems and a treatise on physical aspects
of the living cell. Like Einstein, he also spent much of his later years
seeking to unify gravitation and electromagnetism.
WHAT IS LIFE?
Reasons why Schr. was the great physicist who made such a major contribution
to the history of biological thought: his father, who was spiritual guide of
his formative years, was passionately interested in both biology and botany;
at university, Schr's intimate friendship with Franz Frimmel, a highly
religious student of biology, then reinforced interest in subject - led to
extensive reading in biology, and to his work in the physiology and
biophysics of colour vision.
Schr. due to give 1943 statutory public lectures scheduled for February 1943
at Trinity College, Dublin. Decided to prepare a semi-popular lecture on a
biological subject, the mutation rate caused by action of X rays on the
fruit fly, Drosophila melanogaster (used extensively in lab and field exps
on genetics and evolution because are easy to raise and have short life
cycle - less than 2 wks at room temp). Schr. had learned that the absorption
of one quantum of X-radiation can produce a mutation at one locus in a
chromosome (poss. from Max Delbruck in Berlin, 1933), and in late Sept 1942
he realized that if he knew the absolute intensity of the absorved X rays
and the mutation rate they caused, he could calculate from the target area
the effective size of the information centre in the chromosome - ie the
gene. Mentioned problem to Paul Ewald, who sent him copy of paper from 1935
'Gottinger Nachrichten' by Delbruck, Timofeef-Ressovsky, and Zimmer called
the "green pamphlet" from colour of its reprint covers. This work had
anticipated his estimate of the target area and suggested for the first time
that a mutation is caused by a change at one place in a molecule - this
result was entirely new, and Schr. began to think about its implications for
the physical and chemical mechanism of inheritance. Result was that he
decided to give a series of three lectures entitled "What is Life?"
First lecture on 5 Feb, and two more followed on successive Fridays - de
Valera attending, with other notables from church and state (attendance at
more than 400). As soon as finished, began preparing them for publication as
book: basic question of book was - How can the events in space and time
which take place within the boundary of a living organism be accounted for
by physics and chemistry? Said that at present these sciences cannot answer
this question, but in future will be able to do so. Reason no answer can be
given now is that the most essential part of the living cell - the
chromosome fibre - is piece of matter entirely different than any previously
studied by physicists. It may, he famously stated, be suitably called an
'aperiodic crystal': by which he meant a regular array of repeating units in
which the individual units are not all the same - "Incredibly small groups
of atoms, much too small to display exact statistical laws, do play a
dominating role in the very orderly and lawful events within a living
organism". Schr. then gave an overview of current understanding of mechanism
of heredity - in terms of chromosomes, genes, mitosis, meiosis, and crossing
over - and introduced what was to become one of the most fundamental
concepts in the new science of molecular biology - that the chromosome is a
message written in code:
"In calling the chromosome fibre a code-script we mean that its structure
determines whether the egg would develop, under suitable conditions, into a
black cock or into a speckled hen, into a fly or a maize plant, a
rhododendron, a beetle, a mouse or a woman . . . But the term code-script
is, of course, too narrow. The chromosome structures are at the same time
instrumental in bringing about the development they foreshadow. They are
law-code and executive power - or to use another simile, they are
architect's plan and builder's craft - in one."
This = the birth of the concept of the genetic code. While a few earlier
works had hinted at idea of a code in the chromosomes, Schr. was first to
state the concept in clear physical terms. The chromosome fibre is a linear
code for the info that constitutes the genotype of a particular individual
organism; the smallest locus in the chromosome coding for an individual
difference in the genotype is called the gene - defined by Schr. as "the
hypothetical material carrier of a definite hereditary feature". From
crossing-over data and microscopic exams of giant salivary-gland chromosomes
from Drosophila, seemed that at most a gene can contain a few million atoms:
Schr. guessed that gene is probably a large protein molecule, but almost
simultaneously Oswald Avery, at Rockefeller Inst. for Medical Research in
NY, was writing up exps which showed that the "transforming principle" in
Pneumococcus is not a protein but is in the DNA (deoxyribonucleic acid)
fraction from the cell nuclei.
Schr. then described 'mutations' as the appearance of a discontinuous or
"jump-like" change, occurring in a few individuals out of a large population
(which mainly reproduces individuals without appreciable change for
generations), in which there are no intermediate forms between the few
changed and the many unchanged. A mutation therefore "reminds a physicist of
quantum theory - no intermediate energies occurring between two neighbouring
energy levels".
Based on explanation by Heitler and London (1927) of existence of stable
chemical bonds between atoms in molecules - the first quantum mechanical
theory of the chemical bond. Schr. then stated that the nature of the
chemical bond is essentially the same in molecules and crystals - thus gene
molecule can be regarded as an aperiodic crystal, a long linear molecule in
which the units are not identical but consist of a small number of moieties
that can serve as the symbols in the code scripts - like dots and dashes in
Morse code. As an example, he considered a code made up of 25 units
consistin g of 5 each of 5 different symbols: he calculated that there are
62 x 10[to the power of]12 possible combinations. How the "miniature code"
should be in correspondence with "a highly complicated and specified plan of
development", and how it should "somehow contain the means of putting it
into operation", was however as yet unanswerable, tho Schr. was convinced
that answers wd come via biochemistry guided by physiology and genetics.
Schr then made statement that, when lectures were published, inspired many
young physicists to turn to research in biology: "From Delbruck's general
picture of the hereditary substance it emerges that living matter, while not
eluding the 'laws of physics' as established up to date, is likely to
involve 'other laws of physics' hitherto unknown, which, however, once they
have been revealed, will form just as integral a part of this science".
Believed that these other laws of physics wd be related to the ability of a
living organism to maintain itself in an ordered state and to evade the
tendency towards equilibrium of all non-living systems. Finally concluded,
rather anticlimatically, that new kind of physical law in live is old one:
that the living organism is based on pure mechanism, but governed by "the
Lord's quantum mechanics".
Bk ended with new mystical last chapter, "On Determinism and Free Will", in
which Schr controversially (esp for Ireland) attacked western religion,
accusing Christians of "gross superstition" for their belief in individual
souls, and instead recalled the idea of the earliest Upanishads (ancient
Hindu sacred texts, which form basis of much later Indian philosophy): Atman
= Brahman, the personal self is identical with the all-comprehending
universal self - essence of Vedanta. (N.B. Schr's own metaphysical outlook
expressed in his last published book, 'Meine Weltansicht' - My View of the
World', 1961 - against closely paralleled the mysticism of the Vedanta -
ancient school of Hindu philosophy and teaching). Didn't make "What Is
Life?" popular in Ireland: publication refused, and finally appeared in late
1944 published by CUP in England.
"What Is Life?" had an enormous influence, not only upon physicists - who
were persuaded that their methods might solve the problems of biology - but
also among biologists, who were encouraged to think more rigorously in terms
of mathematically formulated and physically testable models. Bk was
translated into seven languages and total sales are estimated at over
100,000 copies. Bk inspired National Academy of Sciences conference in
Washington on "borderline problems in physics and biology", and had
determining influence on, among others, the career of James Watson: he read
book in spring of 1946, while an undergraduate at Chicago and undecided what
to do and where to go for graduate work - from that time became devoted to
idea of discovering secret of gene. Francis Crick thought bk was "peculiarly
influential" and "attracted people who might otherwise not have entered
biology at all" - although he himself was sceptical and put off by Schr's
mystical last chapter. Maurice Wilkins reported that "Schr's book had a very
positive effect on me and got me, for the first time, interested in
biological problems." Although there is no doubt that molecular biology wd
have developed without "What Is Life?", it wd have been at a slower pace and
without some of same people: is no other instance in history of science in
which a short semi-popular book catalyzed the future development of a great
field of research. Influence of bk continues to be felt.
Crick & Watson: Although had already become interested in population
genetics, James Watson has often said that decisive influence on him was
Schrodinger's 'What Is Life?' (1944). Short work that speculated about the
physical basis - ie the atomic and molecular basis - of biological
phenomena. In it Schrodinger, the founder of quantum mechanics in its modern
form, an Austrian of Roman Catholic background living in quiet exile in
Dublin, popularized some suggestions about the nature of the gene, in the
light of the principles of quantum mechanics, which had been made in Berlin
in 1935 in youthful paper by another physicist, Max Delbruck. From moment
Watson read Schrodinger's book, he wrote, "I became polarized towards
finding out the secret of the gene". (Also became a devotee of Delbruck).
Oddities:
According to Dirac, Schr. was unconventional: "When he went to the Solvay
conference in Brussels, he would walk from the station to the hotel where
the delegates stayed, carrying all his luggage in a rucksack and looking so
like a tramp that it needed a great deal of argument at the reception desk
before he could claim a room".
Had equally unconventional personal life: had entirely open marriage and
numerous affairs throughout life (tolerated by wife, who had long affair of
own ), and lived effectively with two wives in Graz - his own, Annemarie
Bertel, and that of another man, Hilde March (wife of physicist Arthur
March, with whom had a child (Ruth March-Braunizer, b. 1934). Is believed
that reason he declined offer of prestigious American professorship at
Princeton (1934) was expected US disapproval of his unusual family
arrangements - living with wife and lover, with both women sharing care of
his child, plus worried about New Jersey law about bigamy. Continued this
life throughout 1930s, and in Ireland where strangely was tolerated.
Odd hobbies: in Ireland, made study of Gaelic, Irish music and Celtic
design; spent spare time making tiny doll-house furniture with textiles
woven on midget Irish loom. Plus also a poet, and became skilled as a
sculptor.