Category: Astronomy, physic, …

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TimeWorld 2019

TimeWorld values connected intelligence
International Congress on Time in Paris (21, 22, 23 November 2019)

Can we live without a calendar? Does DNA record the passage of time? Do atoms take their time? Biological immortality: fiction or reality? Are musicians time makers? If you have these and many other questions about the weather, TimeWorld is for you.
Through conferences, round tables, shows, workshops, all participants contribute to the current reflection on time.

Youtube channel

Can we measure the Time?

Is the time of the gnomons back?

Time is finally a construction

Can we really travel to the future?

Can we say that the Universe has 13.8 bilion years?

Time perception: after one year of isolation

A single time for all, or each one his own?

Can we take over the time?

Chronobiology

What do you think time is?

Time of brands

Time according to Laurent Lafforgue

Time in the cinema

Perception of time in Japan

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Atomic Clock

The first atomic clock was an ammonia absorption line device at 23870.1 MHz built in 1949 at the U.S.

The first accurate atomic clock, a caesium standard based on a certain transition of the caesium-133 atom, was built by Louis Essen and Jack Parry in 1955 at the National Physical Laboratory in the UK.

Louis Essen (right) and Jack Parry (left) standing next to the world’s first caesium-133 atomic clock.

A brief history of timekeeping

Innovation in Laboratory Time and Frequency, Neuchâtel

Norman Ramsey, in the origin of atomic clocks (French)

What are atomic clocks used for? Lemonde.fr

What is an atomic clock? with Pierre Thomann, RTS archive