Grand-mother clocks and quiet lasers

8 J an 2 00 9 Grand - mother clocks and quiet lasers .

Galileo noted in the 16 century that the period of oscillation of a pendulum is almost independent of the amplitude. However, such a pendulum is damped by air friction. The latter may be viewed as resulting from air molecules getting in contact with the pendulum. It follows that air friction, not only damps the oscillation, but also introduces randomness. In the so-called “grand-mother” clock, ...

Quiet Lasers

Lasers, Cold Atoms and Atomic Clocks: Realizing the Second Today

The time is the physical quantity that mankind could measure with the best accuracy, thanks to the properties of the atomic physics, as the present definition of time is based on atomic energy transitions. This short review gives some basic information on the heart of the measurement of time in the contemporary world, i.e. the atomic clocks, and some trends related.

Introduction to the Special issue Spectroscopic Tests of Fundamental Physics

http://dx.doi.org/10.1016/j.jms.2014.04.004 0022-2852/ 2014 Elsevier Inc. All rights reserved. This special issue of the Journal of Molecular Spectroscopy highlights the recent advances in the use of molecular spectroscopy to test fundamental physics. It follows a special session on the same subject at the 68th International Symposium of Molecular Spectroscopy held on 17–18 June 2013 at The Ohi...

The Relationship between Maternal-Fetal Attachment and Mother-Infant Attachment Behaviors in Primiparous Women Referring to Mashhad Health Care Centers

Background & aim: Mother-infant bonding and interactions after childbirth are shaped by maternal-fetal attachment during pregnancy. Although many studies have shown the positive correlation between maternal-fetal attachment and mother-infant attachment behaviors, some controversial studies have shown otherwise. Therefore, this study aimed to evaluate the correlation between maternal-fetal attac...