John Strutt, 3rd Baron Rayleigh
Encyclopedia
John William Strutt, 3rd Baron Rayleigh, OM
(12 November 1842 – 30 June 1919) was an English
physicist
who, with William Ramsay
, discovered the element argon
, an achievement for which he earned the Nobel Prize for Physics in 1904. He also discovered the phenomenon now called Rayleigh scattering
, explaining why the sky is blue, and predicted the existence of the surface wave
s now known as Rayleigh waves. Rayleigh's textbook, The Theory of Sound, is still referred to by acoustic engineers today.
, and in his early years suffered from frailty and poor health. He attended Harrow School
, before going on to the University of Cambridge
in 1861 where he studied mathematics at Trinity College
. He obtained a Bachelor of Arts
degree (Senior Wrangler and 1st Smith's prize
) in 1865, and a Master of Arts in 1868. He was subsequently elected to a Fellowship of Trinity. He held the post until his marriage to Evelyn Balfour, daughter of James Maitland Balfour
, in 1871. He had three sons with her. In 1873, on the death of his father, John Strutt, 2nd Baron Rayleigh, he inherited the Barony of Rayleigh
.
He was the second Cavendish Professor of Physics
at the University of Cambridge
(following James Clerk Maxwell
), and held this position from 1879 to 1884. He first described dynamic soaring
by seabirds in 1883, in the British journal Nature
. From 1887 to 1905 he was Professor of Natural Philosophy
at Cambridge.
Around the year 1900 Lord Rayleigh developed the Duplex (combination of two) Theory
of human sound localization using two binaural cues
, interaural time delay (ITD) and interaural level difference (ILD) (assuming a spherical head with no external pinnae). Humans perceive sound sources spatially, using the difference in the phase (time delay) of the sound and the difference in amplitude (level) between the two ears, in a similar way that stereoscopic sight provides depth perception. The theory posits that we use two primary cues for azimuth (horizontal location) as well as for a 3-dimensional bearing, although pinnae reflections are considered a main cue for vertical localisation. For example, when you hear a seagull call, you can determine roughly the location of the sound on mental x, y, and z axes.
Lord Rayleigh was elected Fellow of the Royal Society
on 12 June 1873, and served as president of the Royal Society from 1905 to 1908. From time to time Lord Rayleigh participated in the House of Lords
; however, he spoke up only if politics attempted to become involved in science. He died on 30 June 1919, in Witham, Essex. He was succeeded, as the 4th Lord Rayleigh, by his son Robert John Strutt, another well known physicist.
s on Mars
and the Moon
are named in his honor as well as a type of surface wave known as a Rayleigh wave. The asteroid
22740 Rayleigh
was named in his honour on 1 June 2007.
Order of Merit
The Order of Merit is a British dynastic order recognising distinguished service in the armed forces, science, art, literature, or for the promotion of culture...
(12 November 1842 – 30 June 1919) was an English
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...
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...
who, with William Ramsay
William Ramsay
Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...
, discovered the element argon
Argon
Argon is a chemical element represented by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table . Argon is the third most common gas in the Earth's atmosphere, at 0.93%, making it more common than carbon dioxide...
, an achievement for which he earned the Nobel Prize for Physics in 1904. He also discovered the phenomenon now called Rayleigh scattering
Rayleigh scattering
Rayleigh scattering, named after the British physicist Lord Rayleigh, is the elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the light. The particles may be individual atoms or molecules. It can occur when light travels through...
, explaining why the sky is blue, and predicted the existence of the surface wave
Surface wave
In physics, a surface wave is a mechanical wave that propagates along the interface between differing media, usually two fluids with different densities. A surface wave can also be an electromagnetic wave guided by a refractive index gradient...
s now known as Rayleigh waves. Rayleigh's textbook, The Theory of Sound, is still referred to by acoustic engineers today.
Biography
Strutt was born in Langford Grove, EssexEssex
Essex is a ceremonial and non-metropolitan county in the East region of England, and one of the home counties. It is located to the northeast of Greater London. It borders with Cambridgeshire and Suffolk to the north, Hertfordshire to the west, Kent to the South and London to the south west...
, and in his early years suffered from frailty and poor health. He attended Harrow School
Harrow School
Harrow School, commonly known simply as "Harrow", is an English independent school for boys situated in the town of Harrow, in north-west London.. The school is of worldwide renown. There is some evidence that there has been a school on the site since 1243 but the Harrow School we know today was...
, before going on to the University of Cambridge
University of Cambridge
The University of Cambridge is a public research university located in Cambridge, United Kingdom. It is the second-oldest university in both the United Kingdom and the English-speaking world , and the seventh-oldest globally...
in 1861 where he studied mathematics at Trinity College
Trinity College, Cambridge
Trinity College is a constituent college of the University of Cambridge. Trinity has more members than any other college in Cambridge or Oxford, with around 700 undergraduates, 430 graduates, and over 170 Fellows...
. He obtained a Bachelor of Arts
Bachelor of Arts
A Bachelor of Arts , from the Latin artium baccalaureus, is a bachelor's degree awarded for an undergraduate course or program in either the liberal arts, the sciences, or both...
degree (Senior Wrangler and 1st Smith's prize
Smith's Prize
The Smith's Prize was the name of each of two prizes awarded annually to two research students in theoretical Physics, mathematics and applied mathematics at the University of Cambridge, Cambridge, England.- History :...
) in 1865, and a Master of Arts in 1868. He was subsequently elected to a Fellowship of Trinity. He held the post until his marriage to Evelyn Balfour, daughter of James Maitland Balfour
James Maitland Balfour
James Maitland Balfour , of Whittinghame, Berwickshire, was a Scottish Member of Parliament. He was the father of Prime Minister Arthur Balfour, 1st Earl of Balfour....
, in 1871. He had three sons with her. In 1873, on the death of his father, John Strutt, 2nd Baron Rayleigh, he inherited the Barony of Rayleigh
Baron Rayleigh
Baron Rayleigh, of Terling Place in the County of Essex, is a title in the Peerage of the United Kingdom. It was created in 1821 for Lady Charlotte Strutt, wife of Colonel Joseph Strutt, Member of Parliament for Maldon and a member of an Essex family that had made its fortune in the milling business...
.
He was the second Cavendish Professor of Physics
Cavendish Professor of Physics
The Cavendish Professorship is one of the senior Professorships in Physics at Cambridge University. It was founded by grace of 9 February 1871 alongside the famous Cavendish Laboratory which was completed three years later...
at the University of Cambridge
University of Cambridge
The University of Cambridge is a public research university located in Cambridge, United Kingdom. It is the second-oldest university in both the United Kingdom and the English-speaking world , and the seventh-oldest globally...
(following James Clerk Maxwell
James Clerk Maxwell
James Clerk Maxwell of Glenlair was a Scottish physicist and mathematician. His most prominent achievement was formulating classical electromagnetic theory. This united all previously unrelated observations, experiments and equations of electricity, magnetism and optics into a consistent theory...
), and held this position from 1879 to 1884. He first described dynamic soaring
Dynamic soaring
Dynamic soaring is a flying technique used to gain energy by repeatedly crossing the boundary between air masses of significantly different velocity...
by seabirds in 1883, in the British journal Nature
Nature (journal)
Nature, first published on 4 November 1869, is ranked the world's most cited interdisciplinary scientific journal by the Science Edition of the 2010 Journal Citation Reports...
. From 1887 to 1905 he was Professor of Natural Philosophy
Natural philosophy
Natural philosophy or the philosophy of nature , is a term applied to the study of nature and the physical universe that was dominant before the development of modern science...
at Cambridge.
Around the year 1900 Lord Rayleigh developed the Duplex (combination of two) Theory
Interaural time difference
The interaural time difference when concerning humans or animals, is the difference in arrival time of a sound between two ears. It is important in the localisation of sounds, as it provides a cue to the direction or angle of the sound source from the head. If a signal arrives at the head from one...
of human sound localization using two binaural cues
Binaural
Binaural literally means "having or relating to two ears." Binaural hearing, along with frequency cues, lets humans and other animals determine direction of origin of sounds...
, interaural time delay (ITD) and interaural level difference (ILD) (assuming a spherical head with no external pinnae). Humans perceive sound sources spatially, using the difference in the phase (time delay) of the sound and the difference in amplitude (level) between the two ears, in a similar way that stereoscopic sight provides depth perception. The theory posits that we use two primary cues for azimuth (horizontal location) as well as for a 3-dimensional bearing, although pinnae reflections are considered a main cue for vertical localisation. For example, when you hear a seagull call, you can determine roughly the location of the sound on mental x, y, and z axes.
Lord Rayleigh was elected Fellow of the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...
on 12 June 1873, and served as president of the Royal Society from 1905 to 1908. From time to time Lord Rayleigh participated in the House of Lords
House of Lords
The House of Lords is the upper house of the Parliament of the United Kingdom. Like the House of Commons, it meets in the Palace of Westminster....
; however, he spoke up only if politics attempted to become involved in science. He died on 30 June 1919, in Witham, Essex. He was succeeded, as the 4th Lord Rayleigh, by his son Robert John Strutt, another well known physicist.
Honours and awards
CraterImpact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
s on Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
and the Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
are named in his honor as well as a type of surface wave known as a Rayleigh wave. The asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
22740 Rayleigh
22740 Rayleigh
22740 Rayleigh is an outer main-belt asteroid discovered on September 20, 1998 by Eric Walter Elst at the European Southern Observatory. It is one of very few asteroids located in the 2 : 1 mean motion resonance with Jupiter....
was named in his honour on 1 June 2007.
- Smith's PrizeSmith's PrizeThe Smith's Prize was the name of each of two prizes awarded annually to two research students in theoretical Physics, mathematics and applied mathematics at the University of Cambridge, Cambridge, England.- History :...
(1864) - Royal MedalRoyal MedalThe Royal Medal, also known as The Queen's Medal, is a silver-gilt medal awarded each year by the Royal Society, two for "the most important contributions to the advancement of natural knowledge" and one for "distinguished contributions in the applied sciences" made within the Commonwealth of...
(1882) - Matteucci MedalMatteucci MedalThe Matteucci Medal was established to award physicists for their fundamental contributions. Under an Italian Royal Decree dated July 10, 1870, the Italian Society of Sciences was authorized to receive a donation from Carlo Matteucci for the establishment of the Prize.Matteucci Medalists* 1868...
(1894) - Member of the Royal Swedish Academy of SciencesRoyal Swedish Academy of SciencesThe Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...
(1897) - Copley MedalCopley MedalThe Copley Medal is an award given by the Royal Society of London for "outstanding achievements in research in any branch of science, and alternates between the physical sciences and the biological sciences"...
(1899) - Order of MeritOrder of MeritThe Order of Merit is a British dynastic order recognising distinguished service in the armed forces, science, art, literature, or for the promotion of culture...
(1902) - Nobel Prize for Physics (1904)
- Elliott Cresson MedalElliott Cresson MedalThe Elliott Cresson Medal, also known as the Elliott Cresson Gold Medal, was the highest award given by the Franklin Institute. The award was established by Elliott Cresson, life member of the Franklin Institute, with $1,000 granted in 1848...
(1913) - Rumford MedalRumford MedalThe Rumford Medal is awarded by the Royal Society every alternating year for "an outstandingly important recent discovery in the field of thermal or optical properties of matter made by a scientist working in Europe". First awarded in 1800, it was created after a 1796 donation of $5000 by the...
(1914 & 1920)
See also
- Rayleigh criterionAngular resolutionAngular resolution, or spatial resolution, describes the ability of any image-forming device such as an optical or radio telescope, a microscope, a camera, or an eye, to distinguish small details of an object...
- Rayleigh fadingRayleigh fadingRayleigh fading is a statistical model for the effect of a propagation environment on a radio signal, such as that used by wireless devices.Rayleigh fading models assume that the magnitude of a signal that has passed through such a transmission medium will vary randomly, or fade, according to a...
- Rayleigh numberRayleigh numberIn fluid mechanics, the Rayleigh number for a fluid is a dimensionless number associated with buoyancy driven flow...
- Rayleigh quotient
- Rayleigh (unit)Rayleigh (unit)The rayleigh is a unit of photon flux, used to measure air glow . It was first proposed in 1956 by D. M. Hunten, Franklin E. Roach, and J. W. Chamberlain. It is named for Robert John Strutt, 4th Baron Rayleigh . Its symbol is R...
(named after his son Robert John Strutt) - Rayleigh–Jeans law
- Rayleigh lawRayleigh lawThe Rayleigh law describes the behaviour of ferromagnetic materials at low fields.Ferromagnetic materials consist of magnetic domains. When a small external field H is applied, domains parallel to the external field start to grow. In this region, domain walls are moving. They are hindered by...
- Rayleigh distribution
- Rayleigh–Taylor instability
- Plateau–Rayleigh instability
- Rayleigh MedalRayleigh MedalThe Rayleigh Medal is a prize awarded annually by the Institute of Acoustics for "outstanding contributions to acoustics". The prize is named after John Strutt, 3rd Baron Rayleigh.-List of recipients:...
- Rayleigh–Bénard convection
- Rayleigh's method of dimensional analysisRayleigh's method of dimensional analysisRayleigh's method of dimensional analysis is a conceptual tool used in physics, chemistry, and engineering. This form of dimensional analysis expresses a functional relationship of some variables in the form of an exponential equation...
- Experiments of Rayleigh and BraceExperiments of Rayleigh and BraceThe experiments of Rayleigh and Brace were aimed to show whether length contraction leads to birefringence or not. They were some of the first optical experiments measuring the relative motion of Earth and the luminiferous aether which were sufficiently precise to detect magnitudes of second order...