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GAME is a recent concept for a small/medium class mission aimed at Fundamental Physics tests in the Solar
system, by means of an optimised instrument in the visible, based on smart combination of coronagraphy and
Fizeau interferometry. The targeted precision on the γ and β parameters of the Parametrised Post-Newtonian
formulation of General Relativity are respectively in the 10-7-10-8 and 10-5-10-6 range, improving by one or two orders of magnitude with respect to the expectations on current or near future experiments. Such precision
is suitable to detect possible deviations from the unity value, associated to generalised Einstein models for
gravitation, with potentially huge impacts on the cosmological distribution of dark matter and dark energy from
a Solar system scale experiment. The measurement principle is based on the differential astrometric signature on
the stellar positions, i.e. based on the spatial component of the effect rather than the temporal component as in
the most recent experiments using radio link delay timing variation (Cassini). The instrument concept is based
on multiple field, multiple aperture Fizeau interferometry, observing simultaneously regions close to the Solar
limb (requiring the adoption of coronagraphic techniques), and others in opposition to the Sun. The diluted
optics approach is selected for achieving an efficient rejection of the scattered solar radiation, while retaining
an acceptable angular resolution on the science targets. The multiple field observation is aimed at cost-effective
control of systematic effects through simultaneous calibration. We describe the science motivation, the proposed
mission profile, the instrument concept and the expected performance.
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