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It is one of the most important announcement in the past decades. 


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It confirms essentially most of what has been done in physics.

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This year prizes is about something very small that makes all the difference.


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I am rather surprised it has happened in my lifetime.

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At CERN's foundation in 1954, the world of particle physics was a very different one.


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Scientists were trying to come to grips with the plenty of particles observed in Nature.


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They lacked of an overall framework to explain the basic constitution of matter and the forces that act upon them.

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This framework would later become known as the Standard Model.

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By the end of the decade CERN physicists were already providing insight into the weak interaction, 


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a force without which the Sun would not shine.

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The 1960s we saw the birth of electro-weak theory, which unifies the weak and electromagnetic forces.


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A vital part of this is a mechanism that accounts for the vastly different ranges of theses forces,

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as well as for particle masses.

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These were beautiful concepts but they needed experimental evidences to back them up.


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Particle physicists embarked on a global search for the carriers of the weak forces, W and Z bosons,


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whose existence would prove the theorists were right.

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A major breakthrough came in 1973 with the discovery at the PS.

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The Gargamelle experiment identified weak neutron currents, tell tale science of the existence of Z bosons.


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This ground break result brought the first evidence for the electro-weak theory.

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Our physicist were on the right track, but direct detection of weak bosons would take another decade.

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In 1976, CERN brought the SPS on stream.

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Larger and more powerful than CERN's previous accelerators,

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the SPS would go on to collide protons with anti-protons.

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By 1983 SPS experiments had seen W and Z bosons.

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Their long way to discovery led to the Nobel Prize for CERN's Carlo Rubia and Simon Van der Meer.

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"This discovery of the W and Z is not the end, it is the beginning." 


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The next step begun when LEP, the 27 km large electron-positron collider, was switched on, in 1989.

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It was designed to study weak bosons in detail.

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The LEP collaborations soon had their first major result.

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By measuring the decays of Z bosons, they found that Nature has three,

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and only three, families of matter particles.

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Everything we see in the Universe is made of the lightest family.

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During its 11 years of operation, LEP placed electro-weak theory on solid experimental ground.

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The Standard Model was almost complete, but what accounted for the mass of particles?

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There was one last missing piece of the puzzle to

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uncover: the physical manifestation of the Brout-Englert-Higgs mechanism.

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A particle called the Higgs boson.

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Its discovery was in sight. With the construction of Large Hadron Collider,

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CERN would take its first steps into a new century of discovery .

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"Today is a special day."

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On the 4th of July 2012, the CMS and Atlas collaborations announced the discovery of Higgs bosons.

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"Theses results are the outcome of the ingenui division


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and painstaking work of our community from accelerator to detector instrumentation, computing and physics."

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"We have observed the new bosons with mass of 125.3 plus minus 0.6 GeV, at 4.97 deviations."


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It was the final evidence the world has been waiting for, heating headlines around the world,

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winning the Noble Prize for Peter Higgs and François Englert and cementing CERN's pivotal role in the development of the Standard Model.

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The Higgs boson completes the Standard Model, but many questions about our Universe remain unanswered,

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mysteries that will captivate future generations of scientists and lead them to untold discoveries.