Light and the distribution of time
1 Istituto Nazionale di Ricerca Metrologica, INRIM - Strada delle Cacce 91, 10135 Torino, Italy
2 LENS and Dipartimento di Fisica e Astronomia, Università di Firenze - via N. Carrara 1, 50019 Sesto Fiorentino (FI), Italy
Received: 28 April 2015
Accepted: 8 May 2015
Light allows to time travel: light from the Universe offers the possibility to look back to its ancestral epochs, at the very first moments. Nowadays light is also a carrier that allows time to travel, bringing atomic clocks references with the most advanced precision. The frontier of timekeeping and time transfer using light paves the way to unprecedented applications in science and metrology. Light is fundamental in the present effort to redefine the unit of time, to improve our knowledge of fundamental physics laws, geodesy, radioastronomy. Light could be also a new mean to investigate dark matter in the known Universe and possibly to detect gravitational waves.
PACS: 06.30.Ft – Time and frequency / 42.81.Uv – Fiber networks / 42.62.Eh – Metrological applications; optical frequency synthesizers for precision spectroscopy
© EPLA, 2015