Use Of Atomic Clocks Research Articles

Probing bosonic stars with atomic clocks

Dark Matter could potentially manifest itself in the form of asymmetric dark stars. In this paper we entertain the possibility of probing such asymmetric bosonic dark matter stars by the use of atomic clocks. If the dark sector connects to the standard model sector via a Higgs or photon portal, the interior of boson stars that are in a Bose-Einstein condensate state can change the values of physical constants that control the timing of atomic clock devices. Dilute asymmetric dark matter boson stars passing through the Earth can induce frequency shifts that can be observed in separated Earth based atomic clocks. This gives the opportunity to probe a class of dark matter candidates that for the moment cannot be detected with any different conventional method.

Research for Practice: Distributed Transactions and Networks as Physical Sensors

First, Irene Zhang delivers a whirlwind tour of recent developments in distributed concurrency control. If you thought distributed transactions were prohibitively expensive, Irene’s selections may prompt you to reconsider: the use of atomic clocks, clever replication protocols, and new means of commit ordering all improve performance at scale. Second, Fadel Adib provides a fascinating look at using computer networks as physical sensors. It turns out that the radio waves passing through our environment and bodies are subtly modulated as they do so. As Fadel’s selection shows, new techniques for sensing and interpreting these modulations allow us to perform tasks previously reserved for science fiction: seeing through walls, performing gesture recognition, and monitoring breathing.

The Determination of Love's Number K from Tidal Variations of Rotation of a Compressible Earth

Long period bodily tides (fortnightly and monthly) cause periodic changes of the Earth's moment of inertia and consequently the angular speed of its rotation.During the past few years the use of atomic clocks has made it possible to determine the amplitudes of these periodic variations of the Earth's rotation with high accuracy and has made this method very effective in determining Love's number K, which is dependent on the internal structure of the Earth (the most detailed studies were made in the U.S.S.R. – Pilnik and Gubanov).But up to now it was taken (Anderson, Woolard, Melchior, and others), that the formulae of Jeffreys and Woolard, which are used in this method, are valid only for incompressible Earth models.It is shown in this paper that the formulae are valid for the case of an actual compressible heterogeneous Earth. Thus, the method receives a real practical value. The use of lasers and radio methods in the near future will make this method even more effective.The full text of the paper will be published in the magazine Physics of the Earth in No. 3, 1972.

World-Wide Clock Synchronization

To satisfy already existing needs for higher precision in various time measurements, a world-wide system of synchronized clocks is required. One possible method for accomplishing such a system, the transportation of operating precision clocks, is discussed. Particular consideration is given to the use of atomic clocks in this connection, and methods of maintenance of synchronization by means of phase tracking of a central master clock via VLF transmissions are reviewed. Project WOSAC, a Signal Corps project of world-wide synchronization of atomic clocks based upon the principles discussed, is outlined and results already achieved are described.