Philip Tuckey

Bio: Philip Tuckey is an academic researcher from PSL Research University. The author has contributed to research in topics: Time and frequency transfer & Clock network. The author has an hindex of 7, co-authored 16 publications receiving 251 citations.

Exploring the Foundations of the Universe with Space Tests of the Equivalence Principle

Abstract: We present the scientific motivation for future space tests of the equivalence principle, and in particular the universality of free fall, at the $10^{-17}$ level or better. Two possible mission scenarios, one based on quantum technologies, the other on electrostatic accelerometers, that could reach that goal are briefly discussed.

Cold atoms in space: community workshop summary and proposed road-map

Abstract: Abstract We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies.

Time and frequency transfer over a 500 km cascaded White Rabbit network

Abstract: We perform experiments with White Rabbit for time and frequency dissemination over long distance optical fiber links. We consider a unidirectional link setup to ensure compatibility with active telecommunication networks and build the first four-span 500 km cascaded White Rabbit link, using commercial White Rabbit equipment and improved software parameters. We demonstrate a frequency transfer stability at the level of 2 × 10−15 at 200 000 s of integration time. The time transfer stability reaches a minimum of 1.2 ps at 20 seconds of integration time. Finally, we compare our results with infield applications and discuss the limitations of the performance.

Time transfer over a White Rabbit network

Abstract: We started experiments with White Rabbit at LNE-SYRTE for time and frequency dissemination to a large number of users over long haul telecommunication networks. We consider in this paper preliminary work performed on fiber spools, and comparing two situations, one link with one optical fiber and two colors, and a second link with two fibers and a single wavelength. We present preliminary results showing time deviation down to 1 ps at 1000 seconds and Allan deviation as low as 10−15 for about 10000 seconds, for both configurations. We discuss the effect of chromatic dispersion on long haul time transfer regarding stability and accuracy. Finally, we outline our plan for future work.

Search for New Physics with Atoms and Molecules

Abstract: Advances in atomic physics, such as cooling and trapping of atoms and molecules and developments in frequency metrology, have added orders of magnitude to the precision of atom-based clocks and sensors. Applications extend beyond atomic physics and this article reviews using these new techniques to address important challenges in physics and to look for variations in the fundamental constants, search for interactions beyond the standard model of particle physics, and test the principles of general relativity.

Gravitation And Cosmology

Abstract: Thank you for downloading gravitation and cosmology. As you may know, people have search hundreds times for their chosen novels like this gravitation and cosmology, but end up in malicious downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they juggled with some malicious bugs inside their laptop. gravitation and cosmology is available in our book collection an online access to it is set as public so you can get it instantly. Our digital library spans in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the gravitation and cosmology is universally compatible with any devices to read.

A clock network for geodesy and fundamental science.

Abstract: Leveraging the unrivalled performance of optical clocks as key tools for geo-science, for astronomy and for fundamental physics beyond the standard model requires comparing the frequency of distant optical clocks faithfully. Here, we report on the comparison and agreement of two strontium optical clocks at an uncertainty of 5 × 10−17 via a newly established phase-coherent frequency link connecting Paris and Braunschweig using 1,415 km of telecom fibre. The remote comparison is limited only by the instability and uncertainty of the strontium lattice clocks themselves, with negligible contributions from the optical frequency transfer. A fractional precision of 3 × 10−17 is reached after only 1,000 s averaging time, which is already 10 times better and more than four orders of magnitude faster than any previous long-distance clock comparison. The capability of performing high resolution international clock comparisons paves the way for a redefinition of the unit of time and an all-optical dissemination of the SI-second. Comparing the frequency of two distant optical clocks will enable sensitive tests of fundamental physics. Here, the authors compare two strontium optical-lattice clocks 690 kilometres apart to a degree of accuracy that is limited only by the uncertainty of the individual clocks themselves.

Space-borne Bose–Einstein condensation for precision interferometry

Abstract: Owing to the low-gravity conditions in space, space-borne laboratories enable experiments with extended free-fall times. Because Bose–Einstein condensates have an extremely low expansion energy, space-borne atom interferometers based on Bose–Einstein condensation have the potential to have much greater sensitivity to inertial forces than do similar ground-based interferometers. On 23 January 2017, as part of the sounding-rocket mission MAIUS-1, we created Bose–Einstein condensates in space and conducted 110 experiments central to matter-wave interferometry, including laser cooling and trapping of atoms in the presence of the large accelerations experienced during launch. Here we report on experiments conducted during the six minutes of in-space flight in which we studied the phase transition from a thermal ensemble to a Bose–Einstein condensate and the collective dynamics of the resulting condensate. Our results provide insights into conducting cold-atom experiments in space, such as precision interferometry, and pave the way to miniaturizing cold-atom and photon-based quantum information concepts for satellite-based implementation. In addition, space-borne Bose–Einstein condensation opens up the possibility of quantum gas experiments in low-gravity conditions1,2. A Bose–Einstein condensate is created in space that has sufficient stability to enable its characteristic dynamics to be studied.

Optical clock networks

Abstract: This Review covers optical clock networks that are established to synchronize remote optical clocks. Further upgrading of optical clock networks and their impact on a future redefinition of time are also discussed. Within the last decade, optical atomic clocks have surpassed the best cesium clocks, which are used to realize the unit of time and frequency, in terms of accuracy and stability by about two orders of magnitude. When remote optical atomic clocks are connected by links without degradation in the clock signals, an optical clock network is formed, with distinct advantages for the dissemination of time, geodesy, astronomy and basic and applied research. Different approaches for time and frequency transfer in the microwave and optical regime, via satellites and free-space links, optical fibre links, or transportable optical atomic clocks, can be used to form a hybrid clock network that may allow a future redefinition of the unit of time based on an optical reference transition.