Felix Ehrenhaft
Encyclopedia
Felix Ehrenhaft was an Austria
n physicist who contributed to atomic physics
, to the measurement of electrical charges and to the optical properties of metal colloid
s. He was known for his maverick and controversial style. His fearless iconoclasm
was greatly admired by philosopher Paul Feyerabend
.
to physician
Leopold Ehrenhaft and Louise Eggar, the daughter of an Hungarian
industrialist. Ehrenhaft earned his doctorate from the University of Vienna
in 1903, working on the optical
properties of metal
lic colloid
s. He subsequently became assistant to Viktor von Lang
.
s was still disputed but Albert Einstein
and Marian Smoluchowski
had both recently given accounts of Brownian motion
in liquid
s, strongly supporting the atom
ic theory. Though Theodor Svedberg
had made important demonstrations of Brownian motion
in colloid
s, Ehrenhaft extended the work to make observations of particles of silver
in air. The greater mean free path
of air made for a sterner test of the reality of atom
s. Ehrenhaft was awarded the Lieben Prize
of the Vienna Academy of Sciences for his work.
Ehrenhaft adapted his apparatus to measure the elementary charge
and subsequently became involved in a bitter controversy with Robert Millikan
, claiming to have measured an electric charge less than that of a single electron
, Millikan
being passed over for the 1920 Nobel Prize
in physics
owing to the unresolved nature of the debate. Controversy eventually subsided as more and more physicist
s were swayed by Millikan
's results but even as late as 1940, Albert Einstein
wrote:
Even while controversy raged on sub-electronic charges, Ehrenhaft made important and substantial contributions to physics
including the demonstration of photophoresis
and other effects on the interaction of particles with light
. Some of these effects have subsequently been explained in terms of existing phenomena but some still remain poorly understood. He became professor of experimental physics at Vienna
in 1920 and was known as a conscientious researcher and effective lecturer though single-minded to the point of absurdity. Albert Einstein
was a frequent visitor to his home. Following the Anschluss
in 1938, Ehrenhaft emigrated, first to England
, then to the U.S.
where he became a citizen.
. He observed many genuinely surprising and reproducible physical phenomena, usually of ultra-microscopic particles near the limits of perception
. However, he was all too willing to adopt alternate theories to explain experiments that were beset with interactions
and multifactorial cause systems.
From the 1940s, Ehrenhaft's views became increasingly extreme and strident, eventually terminating his good friendship with Albert Einstein
. He found it impossible to obtain either research funding or even a sympathetic hearing in the U.S.
In 1946, he returned to the University of Vienna
where he held again his old position until his death. He became increasingly certain that he had observed magnetic monopole
s, magnetic currents and magnetolysis, the disassociation of liquids by magnet
s rather than electric current
as in electrolysis
.
A review of his life work can be found in the Austrian scientific journal "Acta physica Austriaca", and in the article by Rohatschek on photophoresis
(see sources below).
Austrians
Austrians are a nation and ethnic group, consisting of the population of the Republic of Austria and its historical predecessor states who share a common Austrian culture and Austrian descent....
n physicist who contributed to atomic physics
Atomic physics
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and...
, to the measurement of electrical charges and to the optical properties of metal colloid
Colloid
A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase and a continuous phase . A colloidal system may be solid, liquid, or gaseous.Many familiar substances are colloids, as shown in the chart below...
s. He was known for his maverick and controversial style. His fearless iconoclasm
Iconoclasm
Iconoclasm is the deliberate destruction of religious icons and other symbols or monuments, usually with religious or political motives. It is a frequent component of major political or religious changes...
was greatly admired by philosopher Paul Feyerabend
Paul Feyerabend
Paul Karl Feyerabend was an Austrian-born philosopher of science best known for his work as a professor of philosophy at the University of California, Berkeley, where he worked for three decades . He lived a peripatetic life, living at various times in England, the United States, New Zealand,...
.
Early years
Ehrenhaft was born in ViennaVienna
Vienna is the capital and largest city of the Republic of Austria and one of the nine states of Austria. Vienna is Austria's primary city, with a population of about 1.723 million , and is by far the largest city in Austria, as well as its cultural, economic, and political centre...
to physician
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...
Leopold Ehrenhaft and Louise Eggar, the daughter of an Hungarian
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...
industrialist. Ehrenhaft earned his doctorate from the University of Vienna
University of Vienna
The University of Vienna is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world...
in 1903, working on the optical
Optics
Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light...
properties of metal
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
lic colloid
Colloid
A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase and a continuous phase . A colloidal system may be solid, liquid, or gaseous.Many familiar substances are colloids, as shown in the chart below...
s. He subsequently became assistant to Viktor von Lang
Viktor von Lang
Viktor von Lang was an Austrian chemist. He is counted among the pioneers and founders of crystal physics.-References:...
.
Middle years
In 1907, the reality of atomAtom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s was still disputed but Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
and Marian Smoluchowski
Marian Smoluchowski
Marian Smoluchowski was an ethnic Polish scientist in the Austro-Hungarian Empire. He was a pioneer of statistical physics and an avid mountaineer.-Life:...
had both recently given accounts of Brownian motion
Brownian motion
Brownian motion or pedesis is the presumably random drifting of particles suspended in a fluid or the mathematical model used to describe such random movements, which is often called a particle theory.The mathematical model of Brownian motion has several real-world applications...
in liquid
Liquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...
s, strongly supporting the atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
ic theory. Though Theodor Svedberg
Theodor Svedberg
Theodor H. E. Svedberg was a Swedish chemist and Nobel laureate, active at Uppsala University. His work with colloids supported the theories of Brownian motion put forward by Einstein and the Polish geophysicist Marian Smoluchowski...
had made important demonstrations of Brownian motion
Brownian motion
Brownian motion or pedesis is the presumably random drifting of particles suspended in a fluid or the mathematical model used to describe such random movements, which is often called a particle theory.The mathematical model of Brownian motion has several real-world applications...
in colloid
Colloid
A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase and a continuous phase . A colloidal system may be solid, liquid, or gaseous.Many familiar substances are colloids, as shown in the chart below...
s, Ehrenhaft extended the work to make observations of particles of silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
in air. The greater mean free path
Mean free path
In physics, the mean free path is the average distance covered by a moving particle between successive impacts which modify its direction or energy or other particle properties.-Derivation:...
of air made for a sterner test of the reality of atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s. Ehrenhaft was awarded the Lieben Prize
Lieben Prize
The Ignaz Lieben Prize is an annual Austrian award for young scientists working in the fields of molecular biology, chemistry, or physics.The Ignaz Lieben Prize has been called the Austrian Nobel Prize. It is similar in intent but somewhat older than the Nobel Prize. The Austrian merchant Ignaz L...
of the Vienna Academy of Sciences for his work.
Ehrenhaft adapted his apparatus to measure the elementary charge
Elementary charge
The elementary charge, usually denoted as e, is the electric charge carried by a single proton, or equivalently, the absolute value of the electric charge carried by a single electron. This elementary charge is a fundamental physical constant. To avoid confusion over its sign, e is sometimes called...
and subsequently became involved in a bitter controversy with Robert Millikan
Robert Millikan
Robert A. Millikan was an American experimental physicist, and Nobel laureate in physics for his measurement of the charge on the electron and for his work on the photoelectric effect. He served as president of Caltech from 1921 to 1945...
, claiming to have measured an electric charge less than that of a single electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
, Millikan
Robert Millikan
Robert A. Millikan was an American experimental physicist, and Nobel laureate in physics for his measurement of the charge on the electron and for his work on the photoelectric effect. He served as president of Caltech from 1921 to 1945...
being passed over for the 1920 Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...
in physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
owing to the unresolved nature of the debate. Controversy eventually subsided as more and more physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
s were swayed by Millikan
Robert Millikan
Robert A. Millikan was an American experimental physicist, and Nobel laureate in physics for his measurement of the charge on the electron and for his work on the photoelectric effect. He served as president of Caltech from 1921 to 1945...
's results but even as late as 1940, Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
wrote:
Even while controversy raged on sub-electronic charges, Ehrenhaft made important and substantial contributions to physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
including the demonstration of photophoresis
Photophoresis
Photophoresis denotes the phenomenon that small particles suspended in gas or liquids start to migrate when illuminated by a sufficiently intense beam of light. The existence of this phenomenon is owed to a non-uniform distribution of temperature of an illuminated particle in a fluid medium...
and other effects on the interaction of particles with light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
. Some of these effects have subsequently been explained in terms of existing phenomena but some still remain poorly understood. He became professor of experimental physics at Vienna
University of Vienna
The University of Vienna is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world...
in 1920 and was known as a conscientious researcher and effective lecturer though single-minded to the point of absurdity. Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
was a frequent visitor to his home. Following the Anschluss
Anschluss
The Anschluss , also known as the ', was the occupation and annexation of Austria into Nazi Germany in 1938....
in 1938, Ehrenhaft emigrated, first to England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
, then to the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
where he became a citizen.
Later years
From the mid-1930s, Ehrenhaft's thinking started to diverge strikingly from the mainstream of physicsPhysics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
. He observed many genuinely surprising and reproducible physical phenomena, usually of ultra-microscopic particles near the limits of perception
Perception
Perception is the process of attaining awareness or understanding of the environment by organizing and interpreting sensory information. All perception involves signals in the nervous system, which in turn result from physical stimulation of the sense organs...
. However, he was all too willing to adopt alternate theories to explain experiments that were beset with interactions
Interaction (statistics)
In statistics, an interaction may arise when considering the relationship among three or more variables, and describes a situation in which the simultaneous influence of two variables on a third is not additive...
and multifactorial cause systems.
From the 1940s, Ehrenhaft's views became increasingly extreme and strident, eventually terminating his good friendship with Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
. He found it impossible to obtain either research funding or even a sympathetic hearing in the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
In 1946, he returned to the University of Vienna
University of Vienna
The University of Vienna is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world...
where he held again his old position until his death. He became increasingly certain that he had observed magnetic monopole
Magnetic monopole
A magnetic monopole is a hypothetical particle in particle physics that is a magnet with only one magnetic pole . In more technical terms, a magnetic monopole would have a net "magnetic charge". Modern interest in the concept stems from particle theories, notably the grand unified and superstring...
s, magnetic currents and magnetolysis, the disassociation of liquids by magnet
Magnet
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, and attracts or repels other magnets.A permanent magnet is an object...
s rather than electric current
Electric current
Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...
as in electrolysis
Electrolysis
In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction...
.
A review of his life work can be found in the Austrian scientific journal "Acta physica Austriaca", and in the article by Rohatschek on photophoresis
Photophoresis
Photophoresis denotes the phenomenon that small particles suspended in gas or liquids start to migrate when illuminated by a sufficiently intense beam of light. The existence of this phenomenon is owed to a non-uniform distribution of temperature of an illuminated particle in a fluid medium...
(see sources below).
Publications
- Ehrenhaft, Felix: Das optische Verhalten der Metallkolloide und deren Teilchengröße, 1903.
- Ehrenhaft, Felix: Über die Messung von Elektrizitätsmengen, die kleiner zu sein scheinen als die Ladung des einwertigen Wasserstoffions oder Elektrons und von dessen Vielfachen abweichen, Kais. Akad. Wiss. Wien, Sitzber. math.-nat. Kl. 119 (IIa) 815-867, 1910
- Ehrenhaft, Felix: Das mikromagnetische Feld, 1926.
- Ehrenhaft, Felix: Die longitudinale und transversale Elektro- und Magnetophorese, Phys. Zeit. 31, 478-485, 1930
- Ehrenhaft, Felix: "Photophoresis and the Influence upon it of Electric and Magnetic fields", Phil. mag. 11 (1931),140-146
- Ehrenhaft, Felix: "Physical and Astronomical information Concerning Particles of the Order of Magnitude of the Wavelength of Light", Journal of the Franklin Institute, vol 230: 381-393 (Sept. 1940)
- Ehrenhaft, Felix and Banet, Leo: "Is there a true magnetism or not" Phil. sci. 8 (1941), 458-462
- Ehrenhaft, Felix: "Stationary Electric and Magnetic Fields in Beams of Light", Nature 147: 25 (Jan. 4, 1941).
- Ehrenhaft, Felix: "Photophoresis and Its Interpretation by Electric and Magnetic Ions", Journal of the Franklin Institute, vol 233 (March 1942), pp. 235–255.
- Ehrenhaft, Felix: "The Magnetic Current", Science 94: 232-233 (Sept 5, 1941).
- Ehrenhaft, Felix and Banet, Leo: "The Magnetic Ion", Science 96: 228-229 (Sept. 4, 1942).
- Ehrenhaft, Felix: "The Magnetic Current in Gases", Physical Review 61: 733 (1942).
- Ehrenhaft, Felix: "Decomposition of Matter Through the Magnet (Magnetolysis)", Physical Review 63: 216 (1943).
- Ehrenhaft, Felix: "Magnetolysis and the Electric Field Around the Magnetic Current", Physical Review 63: 461-462 (1943).
- Ehrenhaft, Felix: "Further Facts Concerning the magnetic Current", Physical Review 64: 43 (1943).
- Ehrenhaft, Felix: "New Experiments about the Magnetic Current", Physical Review 65: 62-63 (1944).
- Ehrenhaft, Felix: "Continuation of Experiments with the Magnetic Current", Physical Review 65: 256 (1944).
- Ehrenhaft, Felix: "The Decomposition of Water by the So-Called Permanent Magnet...", Physical Review 65: 287-289 (May 1944).
- Ehrenhaft, Felix: "The Magnetic Current", Nature 154: 426-427 (Sept. 30, 1944)
- Ehrenhaft, Felix: "On Photophoresis, the true magnetic Charge and on helical Motion of Matter in Fields" (Review of his scientific work part 1, in German), Acta Physica Austriaca 4: 461 - 488 (1951).
- Ehrenhaft, Felix: "On Photophoresis, the true magnetic Charge and on helical Motion of Matter in Fields" (Review of his scientific work part 2, in German), Acta Physica Austriaca 5: 12 - 29 (1952).
See also
- Robert MillikanRobert MillikanRobert A. Millikan was an American experimental physicist, and Nobel laureate in physics for his measurement of the charge on the electron and for his work on the photoelectric effect. He served as president of Caltech from 1921 to 1945...
- Paul FeyerabendPaul FeyerabendPaul Karl Feyerabend was an Austrian-born philosopher of science best known for his work as a professor of philosophy at the University of California, Berkeley, where he worked for three decades . He lived a peripatetic life, living at various times in England, the United States, New Zealand,...
- Viktor SchaubergerViktor SchaubergerViktor Schauberger was an Austrian forester/forest warden, naturalist, philosopher, inventor and Biomimicry experimenter....
- List of physicists
- Nobel Prize controversiesNobel Prize controversiesSubsequent to his death in 1896, the will of Swedish industrialist Alfred Nobel established the Nobel Prizes. Annual prizes were to be awarded for service to humanity in the fields of physics, chemistry, physiology or medicine, literature, and peace. Similarly, the Bank of Sweden Prize in Economic...