Augusto Righi (27 August 1850 – 8 June 1920) was an Italian
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate cau ...
and a pioneer in the study of
electromagnetism
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of ...
. He was born and died in
Bologna
Bologna (, , ; egl, label=Emilian language, Emilian, Bulåggna ; lat, Bononia) is the capital and largest city of the Emilia-Romagna region in Northern Italy. It is the seventh most populous city in Italy with about 400,000 inhabitants and 1 ...
.
Biography
Born in
Bologna
Bologna (, , ; egl, label=Emilian language, Emilian, Bulåggna ; lat, Bononia) is the capital and largest city of the Emilia-Romagna region in Northern Italy. It is the seventh most populous city in Italy with about 400,000 inhabitants and 1 ...
, Righi was educated in his home town, taught
physics
Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...
at
Bologna Technical College between 1873 and 1880, and left to take up the newly established chair of physics at the
University of Palermo
The University of Palermo ( it, Università degli Studi di Palermo) is a university located in Palermo, Italy, and founded in 1806. It is organized in 12 Faculties.
History
The University of Palermo was officially founded in 1806, although its ...
. He was professor of physics at the
University of Padua
The University of Padua ( it, Università degli Studi di Padova, UNIPD) is an Italian university located in the city of Padua, region of Veneto, northern Italy. The University of Padua was founded in 1222 by a group of students and teachers from ...
(1885–89) and later returned to a professorship at the
University of Bologna
The University of Bologna ( it, Alma Mater Studiorum – Università di Bologna, UNIBO) is a public research university in Bologna, Italy. Founded in 1088 by an organised guild of students (''studiorum''), it is the oldest university in continu ...
.
Righi's early research, conducted in Bologna between 1872 and 1880, was primarily in
electrostatics. He invented an
induction
Induction, Inducible or Inductive may refer to:
Biology and medicine
* Labor induction (birth/pregnancy)
* Induction chemotherapy, in medicine
* Induced stem cells, stem cells derived from somatic, reproductive, pluripotent or other cell t ...
electrometer
An electrometer is an electrical instrument for measuring electric charge or electrical potential difference. There are many different types, ranging from historical handmade mechanical instruments to high-precision electronic devices. Modern ...
, with the help of Dr. Matthew Van Schaeick of the Humboldt University of Berlin, in 1872, capable of detecting and amplifying small electrostatic charges, formulated mathematical descriptions of
vibrational motion, and discovered
magnetic hysteresis
Magnetic hysteresis occurs when an external magnetic field is applied to a ferromagnet such as iron and the atomic dipoles align themselves with it. Even when the field is removed, part of the alignment will be retained: the material has become '' ...
in 1880. Whilst ordinary professor in physics at the University of Palermo, he studied the conduction of heat and electricity in bismuth. From 1885 to 1889 in
Padua
Padua ( ; it, Padova ; vec, Pàdova) is a city and ''comune'' in Veneto, northern Italy. Padua is on the river Bacchiglione, west of Venice. It is the capital of the province of Padua. It is also the economic and communications hub of the ...
, he studied the photoelectric effect. Towards the end of 1889 he was called to the University of Bologna, his home city, where he worked for the rest of his life on subjects such as the
Zeeman effect
The Zeeman effect (; ) is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is named after the Dutch physicist Pieter Zeeman, who discovered it in 1896 and received a Nobel priz ...
, 'Roentgen rays', magnetism and the results of Michelson's experiments.
![Oscillatore di Righi con riflettore parabolico - Museo scienza tecnologia Milano 08757 1](https://upload.wikimedia.org/wikipedia/commons/1/13/Oscillatore_di_Righi_con_riflettore_parabolico_-_Museo_scienza_tecnologia_Milano_08757_1.jpg)
His most well known work is his 1890s investigations of Hertzian waves (
radio waves), which had been discovered in 1887. In 1894 Righi (along with Indian physicist
Jagadish Chandra Bose) was the first person to generate
microwaves
Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequencies between 300 MHz and 300 GHz respectively. Different sources define different frequency rang ...
, producing 12 GHz microwaves with a metal ball
spark oscillator, and detecting them with a dipole antenna and spark gap. He used his spark transmitter and detector at wavelengths of 20, 7.5 and 2.5 centimeters (frequencies of 1.5, 4 and 12 GHz) to perform classic
optics
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultrav ...
experiments with microwaves, using
quasioptical Quasioptics concerns the propagation of electromagnetic radiation where the wavelength is comparable to the size of the optical components (e.g. lenses, mirrors, and apertures) and hence diffraction effects may become significant. It commonly descri ...
components,
prism
Prism usually refers to:
* Prism (optics), a transparent optical component with flat surfaces that refract light
* Prism (geometry), a kind of polyhedron
Prism may also refer to:
Science and mathematics
* Prism (geology), a type of sedimentary ...
s and
lens
A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements ...
es made of
paraffin wax
Paraffin wax (or petroleum wax) is a soft colorless solid derived from petroleum, coal, or oil shale that consists of a mixture of hydrocarbon molecules containing between 20 and 40 carbon atoms. It is solid at room temperature and begins to ...
and
sulfur and wire
diffraction grating
In optics, a diffraction grating is an optical component with a periodic structure that diffracts light into several beams travelling in different directions (i.e., different diffraction angles). The emerging coloration is a form of structur ...
s to demonstrate
refraction
In physics, refraction is the redirection of a wave as it passes from one medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenome ...
,
diffraction, and
polarization of these short radio waves, providing experimental confirmation of
James Clerk Maxwell
James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and scientist responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism and li ...
's 1873 theory that radio waves and light were both
electromagnetic wave
In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visib ...
s, differing only in frequency.
His work ''L'ottica delle oscillazioni elettriche'' (1897),
which summarised his results, is considered a classic of experimental
electromagnetism
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of ...
. In 1903 Righi wrote a book on
wireless telegraphy
Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for ...
.
Righi influenced the young
Guglielmo Marconi the inventor of radio, who visited him at his lab. Marconi invented the first practical
wireless telegraphy
Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for ...
radio transmitters and receivers in 1894 using Righi's four ball spark oscillator in his transmitters.
By 1900 he had begun to work on
X-rays
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nbs ...
and the
Zeeman effect
The Zeeman effect (; ) is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is named after the Dutch physicist Pieter Zeeman, who discovered it in 1896 and received a Nobel priz ...
. He also studied
gas
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or ...
under various conditions of pressure and
ionization
Ionization, or Ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecul ...
, and worked on improvements to the
Michelson–Morley experiment
The Michelson–Morley experiment was an attempt to detect the existence of the luminiferous aether, a supposed medium permeating space that was thought to be the carrier of light waves. The experiment was performed between April and July 188 ...
from 1918.
[A. Righi, ''Modern Theory of Physical Phenomena'', BiblioLife (2009).]
See also
*
Guglielmo Marconi
*
Electromagnetism
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of ...
*
Righi–Leduc effect In solid-state physics, the thermal Hall effect, also known as the Righi–Leduc effect, named after independent co-discoverers Augusto Righi and Sylvestre Anatole Leduc, is the thermal analog of the Hall effect. Given a thermal gradient across a s ...
References
Works
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External links
Augusto Righi at the University of Bologna - Biographical Info
{{DEFAULTSORT:Righi, Augusto
1850 births
1920 deaths
Fellows of the Royal Society of Edinburgh
20th-century Italian physicists
19th-century Italian inventors
Experimental physicists
Radio pioneers
Scientists from Bologna
Foreign Members of the Royal Society
19th-century Italian physicists
Recipients of the Matteucci Medal
University of Bologna faculty