We review the results of two double-slit-like experiments in the infrared range, which evidence an anomalous behaviour of photon systems under particular (energy and space) constraints. These outcomes (independently confirmed by crossing photon beam experiments in both the optical and the microwave range) apparently rule out the Copenhagen interpretation of the quantum wave, i.e. the probability wave, by admitting an interpretation in terms of the Einstein-de Broglie-Bohm hollow wave for photons. Moreover, these experiments support the interpretation of the hollow wave as a deformation of the Minkowski space-time geometry. We stress the implications of these experimental results and of their interpretation for the concept of action-at-a-distance, Einstein's relativistic correlation and Bohr's principle of complementarity.