Hi, Some of you may have read this article about defence of Bohmian trajectories against ESSW papers. Quantum Trajectories, Real, Surreal or an Approximation to a Deeper Process? B. J. Hiley, R. E. Callaghan and O. Maroney. http://arxiv.org/abs/quant-ph/0010020 In a nutshell it says ESSW papers And Aharanov made a mistake about bohmian mechanics and indicate that bohmian trajectories are not surrealistic but appropriate for commonsense. I read their papers in detail but the heart of this paper made me confused; "As the atom passes through the interference region I, a new quantum potential energy is generated. It must be emphasised that since this energy arises from equation (25) using equation (1), it must of necessity include the quantum potential energy stored in the ‘cavity’. It is this coupling that gives rise to any exchange of energy between the ‘cavity’ and the atom so that when the atom emerges from the region I, it has regained its original energy and the ‘cavity’ is no longer excited. In other words the process has been truly ‘erased’. If the particle follows the other route, the ‘cavity’ is not excited until the particle reaches the region of interference. Here the wave packet carrying information about the ‘cavity’ comes into effect and energy, in the form of quantum potential energy, is again redistributed so that the cavity becomes excited and the atom loses energy if it is travelling along one of the ‘reflected’ trajectories." It says the alerted cavities' energy is regained by the atom when interfere with its empty wave and adversely, its energy alert the cavity when it interfere with its wave with particle. Is there any bohmians who can explain what's going on?