Pulsar Timing and its Application for Navigation and Gravitational Wave Detection

Pulsars are natural cosmic clocks. On long timescales they rival the precision of terrestrial atomic clocks. Using a technique called pulsar timing, the exact measurement of pulse arrival times allows a number of applications, ranging from testing theories of gravity to detecting gravitational waves. Also an external reference system suitable for autonomous space navigation can be defined by pulsars, using them as natural navigation beacons, not unlike the use of GPS satellites for navigation on Earth. By comparing pulse arrival times measured on-board a spacecraft with predicted pulse arrivals at a reference location (e.g. the solar system barycenter), the spacecraft position can be determined autonomously and with high accuracy everywhere in the solar system and beyond. We describe the unique properties of pulsars that suggest that such a navigation system will certainly have its application in future astronautics. We also describe the on-going experiments to use the clock-like nature of pulsars to "construct" a galactic-sized gravitational wave detector for low-frequency (f_GW ~1E-9 - 1E-7 Hz) gravitational waves. We present the current status and provide an outlook for the future.Comment: 30 pages, 9 figures. To appear in Vol 63: High Performance Clocks, Springer Space Science Review

Creative Tools and Processes to Remain Competitive in the Twenty-First Century

Part 3: Tools and MethodologiesInternational audienceRemaining competitive in the twenty-first century in the world market is more and more difficult. Trying to keep a place in the market on cost and quality alone is not a valid strategy any more: others can do the same product just as well and at a competitive cost. Could teams and larger groups in organizations be more creative using them? This paper describes an experiment done with 300 university and engineering students from around the world during an event named “The 24 hours of innovation” held in 2011. Student teams had to find creative solutions to problems submitted by manufacturing companies in consecutive 24 hours. Results obtains show that many teams using appropriate creativity processes and techniques have well performed in that competition, helping them to create solutions to industrial problems submitted. Those findings could be applied to real organizations facing similar challenge to innovate