Speed read: The importance of asymmetry

Luckily for us, the Universe is not symmetrical, at least at the subatomic level. If it was, the newly formed matter at the Universe’s birth would have been annihilated by an equal and opposite amount of antimatter, and nothingness would have resulted. Instead, a small imbalance, or asymmetry, in the amount of matter and antimatter created led to a slight excess of matter, from which we are all eventually formed. Such ‘broken symmetry’ is one key to our existence

Understanding symmetry, or the lack of it, is an ongoing task, and the 2008 Nobel Prize in Physics rewarded two discoveries concerning symmetry violation in the field of particle physics. In the 1960s Yoichiro Nambu, who had been working on asymmetries underlying superconductivity, was the first to model how broken symmetry can occur spontaneously at the subatomic level. The mathematical descriptions he formulated helped refine the standard model of particle physics, the current working theory that best explains much, but not all, of the way that fundamental particles and the forces that govern their behaviour interact to create the known Universe.

In the early 1970s, Kobayashi and Maskawa formulated a model that explained certain symmetry violations that had recently surprised observers in particle physics experiments. Their model suggested that the collection of subatomic particles known at the time were insufficient to explain the observed behaviours, and predicted the existence of as yet undiscovered elementary particles. It did not, however, specify precisely what form these particles should take. Kobayashi and Maskawa hypothesized the existence of a third family of quarks, which are some of the building blocks from which all matter and antimatter is formed. They then had to wait almost three decades for the experimental results that would verify their hypothesis. The existence of all three families was finally confirmed when the last member was observed in the mid 1990s.

By Adam Smith, Editor-in-Chief, Nobelprize.org
First published 8 October 2008

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Yoichiro Nambu – Photo gallery

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Yoichiro Nambu – Nobel diploma

Nobel diploma

Copyright © The Nobel Foundation 2008
Artist: Roland Jonsson
Calligrapher: Annika Rücker
Photo reproduction: Fredrika Berghult

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Yoichiro Nambu – Nobel Lecture

Spontaneous Symmetry Breaking in Particle Physics: a Case of Cross Fertilization
The Nobel Lecture of Yoichiro Nambu was presented by Giovanni Jona-Lasinio, La Sapienza, University of Rome, Italy, 8 December 2008, at Aula Magna, Stockholm University. He was introduced by Professor Joseph Nordgren, Chairman of the Nobel Committee for Physics.
Presentation

The Nobel Lecture of Yoichiro Nambu was presented by Giovanni Jona-Lasinio, La Sapienza, University of Rome, Italy, 8 December 2008, at Aula Magna, Stockholm University. He was introduced by Professor Joseph Nordgren, Chairman of the Nobel Committee for Physics.

Lecture Slides
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Read the Nobel Lecture
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From Les Prix Nobel. The Nobel Prizes 2008, Editor Karl Grandin, [Nobel Foundation], Stockholm, 2009

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Makoto Kobayashi – Photo gallery

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Makoto Kobayashi – Nobel diploma

Nobel diploma

Copyright © The Nobel Foundation 2008
Artist: Roland Jonsson
Calligrapher: Annika Rücker
Photo reproduction: Fredrika Berghult

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Toshihide Maskawa – Nobel diploma

Nobel diploma

Copyright © The Nobel Foundation 2008
Artist: Roland Jonsson
Calligrapher: Annika Rücker
Photo reproduction: Fredrika Berghult

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Makoto Kobayashi – Banquet speech

Makoto Kobayashi’s speech at the Nobel Banquet in the Stockholm City Hall, 10 December 2008.

Your Majesties, Your Royal Highnesses, Ladies and Gentlemen,

It is great honor for Toshihide Maskawa and me to accept the Nobel Prize in Physics, and we wish to express our sincerest gratitude to the Royal Academy of Science and the Nobel Foundation.

It is a pity that Prof. Yoichiro Nambu was not to attend this ceremony. I am greatly honored to share the Nobel Prize with him. When I entered graduate school, he was already an eminent scholar. I remember studying his theory most intently. My first research subject was on chiral symmetry, which was the direct application of Nambu’s theory for which the Prize has been awarded.

Both Maskawa and I graduated from and earned our PhDs at Nagoya University. At that time, the theoretical particle physics group of Nagoya University was conducting unique research under the mentorship of Professor Shoichi Sakata. Both of us learned a great many things from Prof. Sakata and his group.

The paper on CP violation coauthored with Maskawa was written when we were both doing research at Kyoto University. We are grateful for the support accorded to us by our colleagues at the University.

Many thanks also go to our colleagues who participated in the experiments for verifying our model. In particular, I am personally grateful to the members of the KEK B-factory and Belle Group with whom I have had the privilege of working for many years.

CP violation is an intriguing subject. A fundamental question is why the Universe is made of matter. CP violation holds the keys to solving this problem. In spite of more than 40 years of effort in theoretical and experimental, studies, however, matter dominance of the Universe still remains an open question. I hope to continue pursuing this subject with my colleagues.

Thank you very much for your attention.

Copyright © The Nobel Foundation 2008

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Toshihide Maskawa – Photo gallery

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Makoto Kobayashi – Prize presentation

Watch a video clip of the 2008 Nobel Laureate in Physics, Makoto Kobayashi, receiving his Nobel Prize medal and diploma during the Nobel Prize Award Ceremony at the Concert Hall in Stockholm, Sweden, on 10 December 2008.