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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 ...
who was one of the first scientists to produce
microwave Microwave is a form of electromagnetic radiation with wavelengths shorter than other radio waves but longer than infrared waves. Its wavelength ranges from about one meter to one millimeter, corresponding to frequency, frequencies between 300&n ...
s.


Biography

Born in
Bologna Bologna ( , , ; ; ) is the capital and largest city of the Emilia-Romagna region in northern Italy. It is the List of cities in Italy, seventh most populous city in Italy, with about 400,000 inhabitants and 150 different nationalities. Its M ...
, Righi was educated in his home town, taught
physics Physics is the scientific study of matter, its Elementary particle, 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 whi ...
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 () is a public university, public research university in Palermo, Italy. It was founded in 1806, and is currently organized in 12 Faculties. History The University of Palermo was officially founded in 1806, although it ...
. He was a professor of physics at the
University of Padua The University of Padua (, UNIPD) is an Italian public research university in Padua, Italy. It was founded in 1222 by a group of students and teachers from the University of Bologna, who previously settled in Vicenza; thus, it is the second-oldest ...
(1885–89) and later returned to a professorship at the
University of Bologna The University of Bologna (, abbreviated Unibo) is a Public university, public research university in Bologna, Italy. Teaching began around 1088, with the university becoming organised as guilds of students () by the late 12th century. It is the ...
. Righi's early research, conducted in Bologna between 1872 and 1880, was primarily in
electrostatics Electrostatics is a branch of physics that studies slow-moving or stationary electric charges. Since classical antiquity, classical times, it has been known that some materials, such as amber, attract lightweight particles after triboelectric e ...
. He invented an induction
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 Matthew Van Schaeick of the
Humboldt University of Berlin The Humboldt University of Berlin (, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany. The university was established by Frederick William III on the initiative of Wilhelm von Humbol ...
, 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 an 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 ( ) is a city and ''comune'' (municipality) in Veneto, northern Italy, and the capital of the province of Padua. The city lies on the banks of the river Bacchiglione, west of Venice and southeast of Vicenza, and has a population of 20 ...
, 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 splitting of a spectral line into several components in the presence of a static magnetic field. It is caused by the interaction of the magnetic field with the magnetic moment of the atomic electron associated with ...
,
X-rays An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...
, magnetism and the results of Michelson's experiments. His most well-known work is his 1890s investigations of Hertzian waves (
radio wave Radio waves (formerly called Hertzian waves) are a type of electromagnetic radiation with the lowest frequencies and the longest wavelengths in the electromagnetic spectrum, typically with frequencies below 300 gigahertz (GHz) and wavelengths g ...
s), which had been discovered in 1887. In 1894 Righi (along with Indian physicist
Jagadish Chandra Bose Sir Jagadish Chandra Bose (; ; 30 November 1858 – 23 November 1937) was a polymath with interests in biology, physics and writing science fiction. He was a pioneer in the investigation of radio microwave optics, made significant contributions ...
) was the first person to generate
microwaves Microwave is a form of electromagnetic radiation with wavelengths shorter than other radio waves but longer than infrared waves. Its wavelength ranges from about one meter to one millimeter, corresponding to frequencies between 300 MHz an ...
, 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 centimetres (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 optical instruments, instruments that use or Photodetector, detect it. Optics usually describes t ...
experiments with microwaves, using quasioptical components, prisms and
lens A lens is a transmissive optical device that 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 melting poi ...
and
sulfur Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ...
and wire
diffraction grating In optics, a diffraction grating is an optical grating with a periodic structure that diffraction, diffracts light, or another type of electromagnetic radiation, into several beams traveling in different directions (i.e., different diffractio ...
s to demonstrate
refraction In physics, refraction is the redirection of a wave as it passes from one transmission medium, 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 commo ...
,
diffraction Diffraction is the deviation of waves from straight-line propagation without any change in their energy due to an obstacle or through an aperture. The diffracting object or aperture effectively becomes a secondary source of the Wave propagation ...
, 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 physicist and mathematician who was responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism an ...
's 1873 theory that radio waves and light were both
electromagnetic wave In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength, ...
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 via electromagnetic fields. The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interacti ...
. In 1903 Righi wrote a book on
wireless telegraphy Wireless telegraphy or radiotelegraphy is the transmission of text messages by radio waves, analogous to electrical telegraphy using electrical cable, cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimenta ...
. Righi influenced the young
Guglielmo Marconi Guglielmo Giovanni Maria Marconi, 1st Marquess of Marconi ( ; ; 25 April 1874 – 20 July 1937) was an Italian electrical engineer, inventor, and politician known for his creation of a practical radio wave-based Wireless telegraphy, wireless tel ...
the inventor of radio, who visited him at his lab. Marconi invented the first practical
wireless telegraphy Wireless telegraphy or radiotelegraphy is the transmission of text messages by radio waves, analogous to electrical telegraphy using electrical cable, cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimenta ...
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 (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...
and the
Zeeman effect The Zeeman effect () is the splitting of a spectral line into several components in the presence of a static magnetic field. It is caused by the interaction of the magnetic field with the magnetic moment of the atomic electron associated with ...
. He also studied gas 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 Electric charge, charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged at ...
, and worked on improvements to the
Michelson–Morley experiment The Michelson–Morley experiment was an attempt to measure the motion of the Earth relative to the luminiferous aether, a supposed medium permeating space that was thought to be the carrier of light waves. The experiment was performed between ...
from 1918.A. Righi, ''Modern Theory of Physical Phenomena'', BiblioLife (2009).


See also

*
Guglielmo Marconi Guglielmo Giovanni Maria Marconi, 1st Marquess of Marconi ( ; ; 25 April 1874 – 20 July 1937) was an Italian electrical engineer, inventor, and politician known for his creation of a practical radio wave-based Wireless telegraphy, wireless tel ...
*
Electromagnetism In physics, electromagnetism is an interaction that occurs between particles with electric charge via electromagnetic fields. The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interacti ...
* Righi–Leduc effect


References


Works

* * * * * *


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 Italian experimental physicists Radio pioneers Scientists from Bologna Foreign members of the Royal Society 19th-century Italian physicists Recipients of the Matteucci Medal Academic staff of the University of Bologna