Nicola Cabibbo
Encyclopedia
Nicola Cabibbo was an Italian physicist, best known for his work on the weak interaction
. He was also the president of the Italian National Institute of Nuclear Physics
from 1983 to 1992, and from 1993 until his death he was the president of the Pontifical Academy of Sciences
. He was born in Rome
.
Cabibbo's major work on the weak interaction
originated from a need to explain two observed phenomena:
Cabibbo solved the first issue by postulating weak universality, which involves a similarity in the weak interaction coupling strength between different generations of particles. He solved the second issue with a mixing angle θC (now called the Cabibbo angle), between the down and strange quarks. Modern measurements show that .
Before the discovery of the third generation
of quarks, Cabibbo's work was extended by Makoto Kobayashi
and Toshihide Maskawa
to the Cabibbo–Kobayashi–Maskawa matrix. In 2008, Kobayashi and Maskawa shared one half of the Nobel Prize in Physics
for their work. Some physicists had bitter feelings that the Nobel Prize committee failed to reward Cabibbo for his part. Asked for a reaction on the prize, Cabibbo preferred to give no comment. According to sources close to him, he was very embittered.
Recent work on evaluating the importance of scientific papers using Google
's PageRank
algorithm identifies Cabibbo's paper "Unitary symmetry and leptonic decays" as the top ranked out of 353,268 articles published by the American Physical Society
since 1893 in journals such as Physical Review Letters
. The same research shows that most of the authors of the top-ranked papers are also Nobel Prize winners, which makes Cabibbo's exclusion seem all the more curious.
Later, Cabibbo researched applications of supercomputer
s to address problems in modern physics with the experiments APE 100 and APE 1000.
Cabibbo supported attempts to rehabilitate executed Italian philosopher Giordano Bruno
, citing the apologies on Galileo Galilei
as a possible model to correct the historical wrongs done by the Church.
Weak interaction
Weak interaction , is one of the four fundamental forces of nature, alongside the strong nuclear force, electromagnetism, and gravity. It is responsible for the radioactive decay of subatomic particles and initiates the process known as hydrogen fusion in stars...
. He was also the president of the Italian National Institute of Nuclear Physics
Istituto Nazionale di Fisica Nucleare
The Istituto Nazionale di Fisica Nucleare is the coordinating institution for nuclear, particle and astroparticle physics in Italy. It was founded on the 8th of August 1951, to further the nuclear physics research tradition initiated by Enrico Fermi in Rome, in the 1930s...
from 1983 to 1992, and from 1993 until his death he was the president of the Pontifical Academy of Sciences
Pontifical Academy of Sciences
The Pontifical Academy of Sciences is a scientific academy of the Vatican, founded in 1936 by Pope Pius XI. It is placed under the protection of the reigning Supreme Pontiff. Its aim is to promote the progress of the mathematical, physical and natural sciences and the study of related...
. He was born in Rome
Rome
Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...
.
Work
Weak interaction
Weak interaction , is one of the four fundamental forces of nature, alongside the strong nuclear force, electromagnetism, and gravity. It is responsible for the radioactive decay of subatomic particles and initiates the process known as hydrogen fusion in stars...
originated from a need to explain two observed phenomena:
- The transitions between upUp quarkThe up quark or u quark is the lightest of all quarks, a type of elementary particle, and a major constituent of matter. It, along with the down quark, forms the neutrons and protons of atomic nuclei...
and downDown quarkThe down quark or d quark is the second-lightest of all quarks, a type of elementary particle, and a major constituent of matter. It, along with the up quark, forms the neutrons and protons of atomic nuclei...
quarkQuarkA quark is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. Due to a phenomenon known as color confinement, quarks are never directly...
s, between electronElectronThe 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...
s and electron neutrinoElectron neutrinoThe electron neutrino is a subatomic lepton elementary particle which has no net electric charge. Together with the electron it forms the first generation of leptons, hence its name electron neutrino...
s, and between muonMuonThe muon |mu]] used to represent it) is an elementary particle similar to the electron, with a unitary negative electric charge and a spin of ½. Together with the electron, the tau, and the three neutrinos, it is classified as a lepton...
s and muon neutrinoMuon neutrinoThe muon neutrino is a subatomic lepton elementary particle which has the symbol and no net electric charge. Together with the muon it forms the second generation of leptons, hence its name muon neutrino. It was first hypothesized in the early 1940s by several people, and was discovered in 1962 by...
s had similar likelihood of occurring (similar amplitudesProbability amplitudeIn quantum mechanics, a probability amplitude is a complex number whose modulus squared represents a probability or probability density.For example, if the probability amplitude of a quantum state is \alpha, the probability of measuring that state is |\alpha|^2...
); and - The transitions with change in strangenessStrangenessIn particle physics, strangeness S is a property of particles, expressed as a quantum number, for describing decay of particles in strong and electromagnetic reactions, which occur in a short period of time...
had amplitudes equal to one fourth of those with no change in strangeness.
Cabibbo solved the first issue by postulating weak universality, which involves a similarity in the weak interaction coupling strength between different generations of particles. He solved the second issue with a mixing angle θC (now called the Cabibbo angle), between the down and strange quarks. Modern measurements show that .
Before the discovery of the third generation
Generation (particle physics)
In particle physics, a generation is a division of the elementary particles. Between generations, particles differ by their quantum number and mass, but their interactions are identical....
of quarks, Cabibbo's work was extended by Makoto Kobayashi
Makoto Kobayashi (physicist)
is a Japanese physicist known for his work on CP-violation who was awarded one quarter of the 2008 Nobel Prize in Physics "for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature."- Biography :After completing his PhD at...
and Toshihide Maskawa
Toshihide Maskawa
is a Japanese theoretical physicist known for his work on CP-violation who was awarded one quarter of the 2008 Nobel Prize in Physics "for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature."-Biography:A native of Aichi...
to the Cabibbo–Kobayashi–Maskawa matrix. In 2008, Kobayashi and Maskawa shared one half of the Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
for their work. Some physicists had bitter feelings that the Nobel Prize committee failed to reward Cabibbo for his part. Asked for a reaction on the prize, Cabibbo preferred to give no comment. According to sources close to him, he was very embittered.
Recent work on evaluating the importance of scientific papers using Google
Google
Google Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...
's PageRank
PageRank
PageRank is a link analysis algorithm, named after Larry Page and used by the Google Internet search engine, that assigns a numerical weighting to each element of a hyperlinked set of documents, such as the World Wide Web, with the purpose of "measuring" its relative importance within the set...
algorithm identifies Cabibbo's paper "Unitary symmetry and leptonic decays" as the top ranked out of 353,268 articles published by the American Physical Society
American Physical Society
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...
since 1893 in journals such as Physical Review Letters
Physical Review Letters
Physical Review Letters , established in 1958, is a peer reviewed, scientific journal that is published 52 times per year by the American Physical Society...
. The same research shows that most of the authors of the top-ranked papers are also Nobel Prize winners, which makes Cabibbo's exclusion seem all the more curious.
Later, Cabibbo researched applications of supercomputer
Supercomputer
A supercomputer is a computer at the frontline of current processing capacity, particularly speed of calculation.Supercomputers are used for highly calculation-intensive tasks such as problems including quantum physics, weather forecasting, climate research, molecular modeling A supercomputer is a...
s to address problems in modern physics with the experiments APE 100 and APE 1000.
Cabibbo supported attempts to rehabilitate executed Italian philosopher Giordano Bruno
Giordano Bruno
Giordano Bruno , born Filippo Bruno, was an Italian Dominican friar, philosopher, mathematician and astronomer. His cosmological theories went beyond the Copernican model in proposing that the Sun was essentially a star, and moreover, that the universe contained an infinite number of inhabited...
, citing the apologies on Galileo Galilei
Galileo Galilei
Galileo Galilei , was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism...
as a possible model to correct the historical wrongs done by the Church.
External links
- Cabibbo biography from the Istituto e Museo di Storia della Scienza