Two solid bodies at different temperatures separated by vacuum exchange heat in the form of thermal photons. This exchange of energy is limited in the far field by Stefan-Boltzmann’s law which is a direct consequence of Planck's law. In the near field (when the separation distance is smaller than the thermal wavelength) the flux can overcome this limit by several orders of magnitude due to tunneling of photons making this transfer prominent at nanoscale. Until recently, only the radiative exchange between two objects has been considered in this non-planckian near-field regime. In this project, we propose to develop the very first setup to experimentally investigate the near-field radiative heat exchanges by thermal photons in many-body systems. We will specifically address the case of micrometer-size objects for which the appropriate multipolar theoretical formalism will be developed by our collaborators (P. Ben-Abdallah and R. Messina, Labo. Charles Fabry – IOGS), to go beyond the dipole approximation suited for objects much smaller than the thermal radiation wavelength. To this end, we will: • Install additional probes in the experimental set-up developed by the previous PhD student (from Master ICFP). • Measure the near-field heat exchanges in simple many-body systems by means of multiple interacting SThM probes. In parallel, a general formalism and/or numerical simulations will be developed to study the mutual radiative heat exchanges in many-body systems.