Bragg, William Lawrence

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{{epname|Bragg, William Lawrence}}
 
{{Infobox Scientist
 
{{Infobox Scientist
 
| name = William Lawrence Bragg
 
| name = William Lawrence Bragg
| image = William Lawrence Bragg.jpg|140px
+
| image = Wl-bragg.jpg|140px
 
| caption = William Lawrence Bragg
 
| caption = William Lawrence Bragg
| birth_date = 31 March 1890
+
| birth_date = March 31, 1890
 
| birth_place = [[North Adelaide]], [[South Australia]]
 
| birth_place = [[North Adelaide]], [[South Australia]]
| death_date = 1 July 1971
+
| death_date = July 1, 1971
 
| death_place = [[Ipswich]], [[Suffolk]], [[England]]
 
| death_place = [[Ipswich]], [[Suffolk]], [[England]]
 
| residence = [[Image:Flag_of_Australia.svg|20px|]] [[Australia]], [[Image:Flag_of_the_United_Kingdom.svg|20px|]] [[UK]]  
 
| residence = [[Image:Flag_of_Australia.svg|20px|]] [[Australia]], [[Image:Flag_of_the_United_Kingdom.svg|20px|]] [[UK]]  
Line 14: Line 14:
 
| work_institution = [[Victoria University of Manchester|Victoria University]]<br/>[[Cambridge University]]  
 
| work_institution = [[Victoria University of Manchester|Victoria University]]<br/>[[Cambridge University]]  
 
| alma_mater = [[University of Adelaide]]<br/>[[Cambridge University]]
 
| alma_mater = [[University of Adelaide]]<br/>[[Cambridge University]]
| doctoral_advisor = [[J.J. Thompson]] [[Image:Nobel.svg|20px]]<br/>[[William Henry Bragg|W.H. Bragg]] 20px
+
| doctoral_advisor = [[J.J. Thompson]]
 
| doctoral_students = [[John Crank]]<br/>[[Ronald Wilfried Gurney]]  
 
| doctoral_students = [[John Crank]]<br/>[[Ronald Wilfried Gurney]]  
| known_for = [[X-ray]] diffraction
+
| known_for = [[X-ray]] diffraction
 
| prizes = [[Image:Nobel.svg|20px]] [[Nobel Prize in Physics]] (1915)
 
| prizes = [[Image:Nobel.svg|20px]] [[Nobel Prize in Physics]] (1915)
 
| religion =  
 
| religion =  
 
| footnotes = Youngest person to ever receive a Nobel Prize. He is the son of [[William Henry Bragg|W.H. Bragg]]. Note that the PhD did not exist at Cambridge until 1919, and so [[J.J. Thompson]] and W.H. Bragg were his Master's advisors.  
 
| footnotes = Youngest person to ever receive a Nobel Prize. He is the son of [[William Henry Bragg|W.H. Bragg]]. Note that the PhD did not exist at Cambridge until 1919, and so [[J.J. Thompson]] and W.H. Bragg were his Master's advisors.  
 
}}
 
}}
'''Sir William Lawrence Bragg''' [[Companion of Honour|CH]], [[Royal Society|FRS]], (31 March 1890 1 July 1971) was an [[Australia]]n [[physicist]] who shared the [[Nobel Prize in Physics]] in 1915 with his father [[William Henry Bragg|Sir William Henry Bragg]]. He was the director of the [[Cavendish Laboratory]], Cambridge when the discovery of the structure of DNA was made by [[James Watson]] and [[Francis Crick]] in February 1953. Together with King's College London's Maurice Wilkins, Watson and Crick were awarded the Nobel Prize for Physiology or Medicine in 1962.  
+
'''Sir William Lawrence Bragg''' (March 31, 1890 &ndash; July 1, 1971) was an [[Australia]]n [[physics|physicist]] who independently and in partnership with his father, [[William Henry Bragg]], pioneered the use of [[X-ray]]s for determining the atomic structure of crystalline substances. For their contributions, father and son jointly received the [[Nobel Prize in Physics]] in 1915. The younger Bragg was only 25 at the time, making him the youngest scientist to win the Nobel Prize. Years later, in 1953, he was director of the [[Cavendish Laboratory]], Cambridge, when James Watson and Francis Crick discovered the structure of [[DNA]] (deoxyribonucleic acid).
 +
{{toc}}
 +
== Biography ==
 +
 
 +
Bragg was born in [[North Adelaide]], [[South Australia]]. He showed an early interest in [[science]] and [[mathematics]]. His father was [[William Henry Bragg]], Professor of Mathematics and Physics at the [[University of Adelaide]]. Shortly after starting school at the age of five, Bragg fell from his tricycle and shattered his elbow. His father had read about [[Wilhelm Röntgen|Röntgen]]'s experiments in [[Europe]] of only a year earlier, and built an X-ray apparatus to examine the broken arm, the use of which was salvaged through a painful program of rehabilitation. This is the first recorded diagnostic use of X-rays in [[Australia]].
 +
 
 +
Bragg was a very able student. At age nine, he was sent to Queens preparatory school in North Adelaide. Two years later he was enrolled in St. Peter's College, Adelaide, where he was recognized for his intellectual accomplishments.
 +
 
 +
===University years===
 +
 
 +
In 1906, he went to the University of Adelaide at age 15 to study mathematics, [[chemistry]] and physics. He attributed a lack of interaction with his peers during this period with his failure to develop adequate social skills. His father was somewhat domineering, and compelled Bragg to study with him in his office. But in spite of these discomforts, Bragg graduated in 1908. In the same year his father accepted a job at [[Leeds University]], and brought the family to [[England]]. Bragg entered [[Trinity College, Cambridge]] in the autumn of 1909 and received a major scholarship in mathematics, despite taking the exam while in bed with pneumonia. After initially excelling in mathematics, he transferred to the physics course in the later years of his studies, and graduated in 1911. Among his fellow students during this period was [[Niels Bohr]]. Bragg considered C.T.R. Wilson, who invented the cloud chamber for the visual detection of subatomic particles, his most inspiring teacher. After graduation, he lectured at Trinity and conducted research at the Cavendish Laboratory.
 +
 
 +
===Nobel Prize===
 +
 
 +
Bragg is most famous for his law on the diffraction of [[X-ray]]s by crystals. [[Bragg's law]] makes it possible to calculate the positions of the atoms within a crystal from the way in which an X-ray beam is diffracted by the crystal's orderly array of atoms. He made this discovery in 1912, during his first year as a research student in Cambridge. He discussed his ideas with his father, who later developed the X-ray spectrometer in Leeds. This tool allowed many different types of crystals to be analyzed. The collaboration between father and son led many people to believe that the father had initiated the research, a fact that upset the son.
 +
 
 +
Bragg's research work was interrupted by both [[World War I]] and [[World War II]]. During both wars he worked on sound ranging methods for locating enemy guns. In autumn 1915, his brother Robert was killed. At about the same time William Lawrence Bragg received the news that he had become the youngest person ever to receive the [[Nobel Prize]] in Physics, aged 25. Between the wars, from 1919 to 1937, he worked at the [[Victoria University of Manchester]] as Langworthy Professor of Physics. He married in 1921, to Alice Grace Jenny. The couple had four children. Though the 1920s and 1930s, Bragg continued research into crystal structure using X-rays. As his father was conducting closely related research during this period, the two had to devise a program, however informal, to prevent the duplication of each other's work. Bragg was knighted in 1941. His father died in 1942.
  
== Biography ==
+
After World War II, Bragg returned to Cambridge, splitting the [[Cavendish Laboratory]] into research groups. He believed that the ideal research unit is one of six to twelve scientists and a few assistants. In 1948 Bragg became interested in the structure of proteins and was partly responsible for creating a group that used physics to solve biological problems. He played a major part in the 1953 discovery of the structure of [[DNA]], in that he provided support to [[Francis Crick]] and [[James D. Watson]] who worked under his aegis at the Cavendish. Bragg was gratified to see that the X-ray method that he developed forty years before was at the heart of this profound insight into the nature of life itself. At the same time at the Cavendish [[Max Perutz]] was also doing his [[Nobel Prize]] winning work on the structure of [[haemoglobin]]. Bragg subsequently successfully lobbied for and nominated Crick, Watson and Maurice Wilkins for the 1962 Nobel Prize in Physiology or Medicine.
Bragg was born in [[North Adelaide]], [[South Australia]]. He was an impressionable boy and showed an early interest in science and mathematics. His father, [[William Henry Bragg]], was Professor of Mathematics and Physics at the [[University of Adelaide]]. Shortly after starting school aged 5, William Lawrence Bragg fell from his tricycle and broke his arm. His father had read about [[Wilhelm Röntgen|Röntgen]]'s experiments in Europe of only a year earlier, and used the newly discovered X-rays to examine the broken arm. This combined with a program of rehabilitation enabled Bragg to salvage the use of his arm almost completely. This is the first recorded surgical use of X-rays in Australia.
 
  
Bragg was a very able student. At age 9,  he was sent to Queens preparatory school in North Adelaide. Two years later he was sent to [[St Peter's College, Adelaide, where he found his intellectual accomplishments better rewarded, and was honored for being the top student of his class. In 1906 he went to the University of Adelaide at age 15 to study mathematics, chemistry and physics. He later blamed a lack of interaction with his peers during this period with his failure to develop adequate social skills. His father was domineering, compellling Bragg to study with him in his office. But in spite of these discomforts, Bragg graduated in 1908. In the same year his father accepted a job at [[Leeds University]], and brought the family back to [[England]]. Bragg entered [[Trinity College, Cambridge]] in the autumn of 1909 and received a major scholarship in mathematics, despite taking the exam while in bed with pneumonia. After initially excelling in mathematics, he transferred to the physics course in the later years of his studies, and graduated in 1911.
+
===Later years===
  
Bragg is most famous for his law on the diffraction of [[X-ray]]s by crystals. [[Bragg's law]] makes it possible to calculate the positions of the atoms within a crystal from the way in which an X-ray beam is diffracted by the crystal lattice. He made this discovery in 1912, during his first year as a research student in Cambridge. He discussed his ideas with his father, who developed the X-ray spectrometer in Leeds. This tool allowed many different types of crystals to be analysed. The collaboration between father and son led many people to believe that the father had initiated the research, a fact that upset the son.
+
In April 1953, Bragg accepted the job of Resident Professor at the [[Royal Institution]] in London. He proposed that the Royal Institution should perform some form of public service, and suggested a series of lectures to show experiments to schoolchildren. This idea was met with an enthusiastic response, and by 1965, 20,000 schoolchildren were attending these lectures each year. He worked at the Royal Institution until his retirement in September 1966.
  
Bragg's research work was interrupted by both [[World War I]] and [[World War II]]. During both wars he worked on sound ranging methods for locating enemy guns. In autumn 1915, his brother Robert was killed. At about the same time William Lawrence Bragg received the news that he had become the youngest person ever to receive the [[Nobel Prize]] in Physics, aged 25. Between the wars, from 1919 to 1937, he worked at the [[Victoria University of Manchester]] as Langworthy Professor of Physics. He married in 1921, to Alice Grace Jenny. He was knighted in 1941.  
+
William Lawrence Bragg's hobbies included painting, literature and a lifelong interest in gardening. When he moved to London, he missed having a garden and so worked as a part-time gardener, unrecognized by his employer, until a guest at the house expressed surprise at seeing "Sir Lawrence" there.
  
After World War II, he returned to Cambridge, splitting the [[Cavendish Laboratory]] into research groups. He believed that 'the ideal research unit is one of six to twelve scientists and a few assistants'. In 1948 Bragg became interested in the structure of proteins and was partly responsible for creating a group that used physics to solve biological problems. He played a major part in the 1953 discovery of the structure of [[DNA]], in that he provided support to [[Francis Crick]] and [[James D. Watson]] who worked under his aegis at the Cavendish. Bragg was gratified to see that the X-ray method that he developed forty years before was at the heart of this profound insight into the nature of life itself.  At the same time at the Cavendish [[Max Perutz]] was also doing his [[Nobel Prize]] winning work on the structure of [[haemoglobin]]. Bragg subsequently successfully lobbied for and nominated Crick, Watson and Wilkins for the 1962 Nobel Prize in Physiology or Medicine; Wilkins' share recognised the contribution made by King's College London, under Sir John Randall, to the determination of the structure of DNA and its subsequent validation by the KCL staff.
+
Bragg received both the [[Copley Medal]] and the [[Royal Medal]] of the [[Royal Society]], and in 1967 was made a [[Companion of Honour]] by the [[monarch|Queen]]. He died at a hospital near his home at [[Waldringford]] on July 1, 1971.
  
In April 1953 Bragg accepted the job of Resident Professor at the [[Royal Institution]] in London. He proposed that the Royal Institution should perform some form of public service, and suggested a series of lectures to show experiments to schoolchildren. This idea was met with an enthusiastic response, and by 1965 20,000 schoolchildren were attending these lectures each year. He worked at the Royal Institution until his retirement in September 1966.
+
Since 1992, the [[Australian Institute of Physics]] has awarded the Bragg Gold Medal for Excellence in Physics for the best [[PhD]] thesis by a student at an [[Australian]] [[university]].
  
William Lawrence Bragg's hobbies included painting, literature and a life-long interest in gardening. When he moved to London, he missed having a garden and so worked as a part-time gardener, unrecognised by his employer, until a guest at the house expressed surprise at seeing him there.
+
==X-ray crystallography==
  
Bragg received both the [[Copley Medal]] and the [[Royal Medal]] of the [[Royal Society]], and in 1967 was made a [[Companion of Honour]] by the [[monarch|Queen]]. He died at a hospital near his home at [[Waldringford]] on 1 July 1971.
+
In 1912, [[Max von Laue]], a German physicist, passed X-rays through a crystal, and by the resulting patterns left on X-ray sensitive media, demonstrated that the rays produced an interference pattern similar to that shown by [[light]]. He was not, however, able to explain the pattern by a clear theory of the atomic architecture of the crystals. Bragg successfully interpreted the interference patterns by assuming that the atoms that formed the crystals were arrayed in such a fashion that the faces with the greatest atomic densities formed parallel planes. The X-rays passed through these planes and formed interference patterns when they exited the crystal. He also corrected Laue's interpretation by suggesting a different type of atomic packing in the crystal structure.
  
Since 1992 the [[Australian Institute of Physics]] has awarded the [http://www.aip.org.au/medals/bragg.php Bragg Gold Medal for Excellence in Physics] for the best [[PhD]] thesis by a student at an [[Australian]] [[university]].
+
In one sweep, Bragg both explained the interference patterns and drew conclusions about the distribution of atoms in crystals, thus showing a way in which the crystals of other substances could be analyzed to determine the way in which their atoms are arrayed. Bragg was only 22 at the time of his discovery, and but a year out of graduate school. Bragg's father, William Henry Bragg, later developed a laboratory apparatus called the X-ray spectrometer, which simplified and systematized the analysis of crystals through X-ray diffraction. The two were awarded the Nobel Prize in 1915 for their accomplishments. Laue won the Nobel Prize in 1914 for his discoveries.
  
* spouse = Alice Hopkinson (m. 1921)
+
==Legacy==
* children = Stephen Lawrence, David William, Margaret Alice, Patience Mary
 
  
==Timeline==
+
William Lawrence Bragg could have been easily overshadowed by his father. In fact, when his son was a young boy and found a sea shell that represented a new species, the elder Bragg interfered and prevented the species from being named after him. In spite of this tendency to be overbearing and perhaps antagonistic to his son's achievements, the two were able to work together productively. Each was inspired and instructed by the other, and both produced independently their own discoveries in the same field. Their relationship demonstrates the mutual support that father and son, or a group of scientists, provide one another in their investigations when they work as a team.
* [[Victoria University of Manchester]] (1919–37)
 
* [[Cambridge University]] (1938–53)
 
  
 +
The use of X-ray spectroscopy was eventually applied to organic molecules, and was crucial to deciphering the complex double-helix structure of deoxyribonucleic acid ([[DNA]]), the fundamental molecule of heredity. The latter occurred some 40 years after Bragg and his father received the Nobel Prize for their accomplishments.
  
 
==Prizes==
 
==Prizes==
 +
 
* [[Nobel Prize]] (1915
 
* [[Nobel Prize]] (1915
 
* [[Matteucci Medal]] (1915)
 
* [[Matteucci Medal]] (1915)
Line 63: Line 77:
  
 
== References ==
 
== References ==
<<We need at least 3 reliable references here, properly formatted.>>
+
* Gonzalo, Julio A., and Carmen Aragó López. 2003. ''Great solid state physicists of the 20th century''. River Edge, N.J.: World Scientific. ISBN 9812383360
 +
* Hunter, Graeme K. 2004. ''Light is a messenger: the life and science of William Lawrence Bragg''. New York: Oxford. University Press. ISBN 019852921X.
 +
* Hunter, Graeme K. 2000. ''Vital forces: the discovery of the molecular basis of life''. San Diego: Academic Press. ISBN 012361810X
  
* Biography: "Light Is A Messenger, the life and science of William Lawrence Bragg" by Graeme Hunter, ISBN 0-19-852921-X; Oxford University Press, 2004.
+
{{Nobel Prize in Physics Laureates 1901-1925}}
 
 
* Ridley, Matt; "Francis Crick: Discoverer of the Genetic Code (Eminent Lives)" first published in July 2006 in the USA and then in the UK. September 2006, by HarperCollins Publishers; 192 pp, ISBN 0-06-082333-X; [This short book is in the publisher's "Eminent Lives" series.]
 
 
 
== External links ==
 
 
 
*[http://en.wikipedia.org/wiki/Image:Rosalindfranklinsjokecard.jpg 'Death' of D.N.A. Helix (Crystaline) joke funeral card].
 
*[http://www.packer34.freeserve.co.uk/selectedTATAwebsites.htm] First press stories on D.N.A.
 
*[http://nobelprize.org/nobel_prizes/physics/laureates/1915/index.html Nobelprize.org - The Nobel Prize for Physics in 1915]
 
  
{{Nobel Prize in Physics Laureates 1901-1925}}
 
  
{{Persondata
 
|NAME=Bragg, William Lawrence
 
|ALTERNATIVE NAMES=
 
|SHORT DESCRIPTION=Australian [[physicist]], Nobel Prize for Physiology or Medicine
 
|DATE OF BIRTH=March 31, 1890
 
|PLACE OF BIRTH=[[North Adelaide]], [[South Australia]]
 
|DATE OF DEATH=July 1, 1971
 
|PLACE OF DEATH=[[Waldringford, Australia]]
 
}}
 
  
 
[[Category:Physical sciences]]
 
[[Category:Physical sciences]]
 
[[Category:Biographies of Scientists and Mathematicians]]
 
[[Category:Biographies of Scientists and Mathematicians]]
 
[[Category:Biography]]
 
[[Category:Biography]]
 +
[[Category:Physics]]
  
 
{{credit|123611163}}
 
{{credit|123611163}}

Latest revision as of 15:28, 21 October 2016

William Lawrence Bragg

Wl-bragg.jpg
William Lawrence Bragg
Born

March 31, 1890
North Adelaide, South Australia

Died July 1, 1971

Ipswich, Suffolk, England

Residence Flag of Australia.svg Australia, Flag of the United Kingdom.svg UK
Nationality Flag of Australia.svg Australian-Flag of the United Kingdom.svg English
Institutions Victoria University
Cambridge University
Alma mater University of Adelaide
Cambridge University
Academic advisor  J.J. Thompson
Notable students  John Crank
Ronald Wilfried Gurney
Known for X-ray diffraction
Notable prizes Nobel.svg Nobel Prize in Physics (1915)
Youngest person to ever receive a Nobel Prize. He is the son of W.H. Bragg. Note that the PhD did not exist at Cambridge until 1919, and so J.J. Thompson and W.H. Bragg were his Master's advisors.

Sir William Lawrence Bragg (March 31, 1890 – July 1, 1971) was an Australian physicist who independently and in partnership with his father, William Henry Bragg, pioneered the use of X-rays for determining the atomic structure of crystalline substances. For their contributions, father and son jointly received the Nobel Prize in Physics in 1915. The younger Bragg was only 25 at the time, making him the youngest scientist to win the Nobel Prize. Years later, in 1953, he was director of the Cavendish Laboratory, Cambridge, when James Watson and Francis Crick discovered the structure of DNA (deoxyribonucleic acid).

Biography

Bragg was born in North Adelaide, South Australia. He showed an early interest in science and mathematics. His father was William Henry Bragg, Professor of Mathematics and Physics at the University of Adelaide. Shortly after starting school at the age of five, Bragg fell from his tricycle and shattered his elbow. His father had read about Röntgen's experiments in Europe of only a year earlier, and built an X-ray apparatus to examine the broken arm, the use of which was salvaged through a painful program of rehabilitation. This is the first recorded diagnostic use of X-rays in Australia.

Bragg was a very able student. At age nine, he was sent to Queens preparatory school in North Adelaide. Two years later he was enrolled in St. Peter's College, Adelaide, where he was recognized for his intellectual accomplishments.

University years

In 1906, he went to the University of Adelaide at age 15 to study mathematics, chemistry and physics. He attributed a lack of interaction with his peers during this period with his failure to develop adequate social skills. His father was somewhat domineering, and compelled Bragg to study with him in his office. But in spite of these discomforts, Bragg graduated in 1908. In the same year his father accepted a job at Leeds University, and brought the family to England. Bragg entered Trinity College, Cambridge in the autumn of 1909 and received a major scholarship in mathematics, despite taking the exam while in bed with pneumonia. After initially excelling in mathematics, he transferred to the physics course in the later years of his studies, and graduated in 1911. Among his fellow students during this period was Niels Bohr. Bragg considered C.T.R. Wilson, who invented the cloud chamber for the visual detection of subatomic particles, his most inspiring teacher. After graduation, he lectured at Trinity and conducted research at the Cavendish Laboratory.

Nobel Prize

Bragg is most famous for his law on the diffraction of X-rays by crystals. Bragg's law makes it possible to calculate the positions of the atoms within a crystal from the way in which an X-ray beam is diffracted by the crystal's orderly array of atoms. He made this discovery in 1912, during his first year as a research student in Cambridge. He discussed his ideas with his father, who later developed the X-ray spectrometer in Leeds. This tool allowed many different types of crystals to be analyzed. The collaboration between father and son led many people to believe that the father had initiated the research, a fact that upset the son.

Bragg's research work was interrupted by both World War I and World War II. During both wars he worked on sound ranging methods for locating enemy guns. In autumn 1915, his brother Robert was killed. At about the same time William Lawrence Bragg received the news that he had become the youngest person ever to receive the Nobel Prize in Physics, aged 25. Between the wars, from 1919 to 1937, he worked at the Victoria University of Manchester as Langworthy Professor of Physics. He married in 1921, to Alice Grace Jenny. The couple had four children. Though the 1920s and 1930s, Bragg continued research into crystal structure using X-rays. As his father was conducting closely related research during this period, the two had to devise a program, however informal, to prevent the duplication of each other's work. Bragg was knighted in 1941. His father died in 1942.

After World War II, Bragg returned to Cambridge, splitting the Cavendish Laboratory into research groups. He believed that the ideal research unit is one of six to twelve scientists and a few assistants. In 1948 Bragg became interested in the structure of proteins and was partly responsible for creating a group that used physics to solve biological problems. He played a major part in the 1953 discovery of the structure of DNA, in that he provided support to Francis Crick and James D. Watson who worked under his aegis at the Cavendish. Bragg was gratified to see that the X-ray method that he developed forty years before was at the heart of this profound insight into the nature of life itself. At the same time at the Cavendish Max Perutz was also doing his Nobel Prize winning work on the structure of haemoglobin. Bragg subsequently successfully lobbied for and nominated Crick, Watson and Maurice Wilkins for the 1962 Nobel Prize in Physiology or Medicine.

Later years

In April 1953, Bragg accepted the job of Resident Professor at the Royal Institution in London. He proposed that the Royal Institution should perform some form of public service, and suggested a series of lectures to show experiments to schoolchildren. This idea was met with an enthusiastic response, and by 1965, 20,000 schoolchildren were attending these lectures each year. He worked at the Royal Institution until his retirement in September 1966.

William Lawrence Bragg's hobbies included painting, literature and a lifelong interest in gardening. When he moved to London, he missed having a garden and so worked as a part-time gardener, unrecognized by his employer, until a guest at the house expressed surprise at seeing "Sir Lawrence" there.

Bragg received both the Copley Medal and the Royal Medal of the Royal Society, and in 1967 was made a Companion of Honour by the Queen. He died at a hospital near his home at Waldringford on July 1, 1971.

Since 1992, the Australian Institute of Physics has awarded the Bragg Gold Medal for Excellence in Physics for the best PhD thesis by a student at an Australian university.

X-ray crystallography

In 1912, Max von Laue, a German physicist, passed X-rays through a crystal, and by the resulting patterns left on X-ray sensitive media, demonstrated that the rays produced an interference pattern similar to that shown by light. He was not, however, able to explain the pattern by a clear theory of the atomic architecture of the crystals. Bragg successfully interpreted the interference patterns by assuming that the atoms that formed the crystals were arrayed in such a fashion that the faces with the greatest atomic densities formed parallel planes. The X-rays passed through these planes and formed interference patterns when they exited the crystal. He also corrected Laue's interpretation by suggesting a different type of atomic packing in the crystal structure.

In one sweep, Bragg both explained the interference patterns and drew conclusions about the distribution of atoms in crystals, thus showing a way in which the crystals of other substances could be analyzed to determine the way in which their atoms are arrayed. Bragg was only 22 at the time of his discovery, and but a year out of graduate school. Bragg's father, William Henry Bragg, later developed a laboratory apparatus called the X-ray spectrometer, which simplified and systematized the analysis of crystals through X-ray diffraction. The two were awarded the Nobel Prize in 1915 for their accomplishments. Laue won the Nobel Prize in 1914 for his discoveries.

Legacy

William Lawrence Bragg could have been easily overshadowed by his father. In fact, when his son was a young boy and found a sea shell that represented a new species, the elder Bragg interfered and prevented the species from being named after him. In spite of this tendency to be overbearing and perhaps antagonistic to his son's achievements, the two were able to work together productively. Each was inspired and instructed by the other, and both produced independently their own discoveries in the same field. Their relationship demonstrates the mutual support that father and son, or a group of scientists, provide one another in their investigations when they work as a team.

The use of X-ray spectroscopy was eventually applied to organic molecules, and was crucial to deciphering the complex double-helix structure of deoxyribonucleic acid (DNA), the fundamental molecule of heredity. The latter occurred some 40 years after Bragg and his father received the Nobel Prize for their accomplishments.

Prizes

  • Nobel Prize (1915
  • Matteucci Medal (1915)
  • Royal Medal (1946)
  • Copley Medal (1966)

See also

References
ISBN links support NWE through referral fees

  • Gonzalo, Julio A., and Carmen Aragó López. 2003. Great solid state physicists of the 20th century. River Edge, N.J.: World Scientific. ISBN 9812383360
  • Hunter, Graeme K. 2004. Light is a messenger: the life and science of William Lawrence Bragg. New York: Oxford. University Press. ISBN 019852921X.
  • Hunter, Graeme K. 2000. Vital forces: the discovery of the molecular basis of life. San Diego: Academic Press. ISBN 012361810X

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