The direct test of the absence of the "quantum vampire's" shadow with use of thermal light

Counterintuitive nature of quantum physics leads to a number of paradoxes. One of them is a "quantum vampire" effect [1] consisting in the fact, that photon annihilation in a part of a large beam doesn't change the shape of the beam profile (i. e., doesn't cast a shadow), but may change the total beam intensity. Previously this effect was demonstrated just in a simplified double-mode regime [1,2]. In the current paper the direct test of shadow absence after the photon annihilation has been performed with use of thermal state of light at the input.