CANNEX - a parallel plates approach to physics

Orateur : Rene SEDMIK (Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081 HV Amsterdam,The Netherlands)

Since the discovery of accelerated cosmic expansion dark energy has evolved from a niche subject of cosmology to a focus topic of several related fields. Motivation is given by the cosmological constant problem, originating from the 120 order-of-magnitude discrepancy between actual measurements and the QED prediction for the cosmic vacuum energy density. Among the numerous theories aiming to explain dark energy, one promising candidate introduces a new scalar `chameleon’ particle whose interactions with other matter depend on the local energy density. This variability allows the theory to be in agreement with all present observations but experimental tests have failed to exclude or find evidence for chameleon interactions. In 2010 it has been suggested that a precision force measurement between parallel plates could finally achieve this goal. Another problem related to vacuum energy is the Casimir effect. In MEMS, being widely used in industry and mobile devices, this effect is a major blocker of miniaturization. New geometric structures to overcome the problem are being developed but accurate measurements in geometries involving parallelism are required to verify design methods. Another more fundamental problem in Casimir physics, being discussed already for two decades, is centered around the deep question if real and virtual photons behave in the same way. An unambiguous answer could be given by accurate force measurements at large separation - only possible using the parallel plate geometry. After a six-year construction phase the Casimir and Non-Newtonian force EXperiment (CANNEX), devised to detect sub-pN forces between macroscopic plane parallel plates, is starting to give first data. While the experiment is still in the prototype stage, its unique configuration could yield a wealth of metrological force data, answering long-standing questions in two different fields of physics. In this talk, I will present the problems, perspectives, and status of CANNEX.

Télécharger dans mon agenda