According to the Copenhagen interpretation of quantum theory, it cannot be decided which slit the particle goes through because of the self-interference effect. It has to be assumed that the particle goes through three slits and the wavefunction collapses when a measurement is made at the detector screen.

The Bohmian interpretation is completely different. The quantum particle passes through one of the three slits. Which slit the particles pass through depends on the initial position only. The quantum particles possess well-defined positions and velocities at all times, but these variables can never be measured simultaneously, because of the uncontrollable particle-apparatus coupling. In the causal interpretation of quantum theory there is a quantum force proportional to , where is called the quantum potential. The quantum potential leads to highly nonclassical motion of particles, because the quantum potential from the second and third slits affect the motion of the particle, which evolves from the first slit immediately. So the information of the whole triple slit apparatus is contained in , which Bohm and Hiley later called active information. The trajectories run to the local maxima of the squared wavefunction and therefore correspond to the bright fringes of the diffraction pattern.

The trajectories in - space do not display in real space, but the structure in real - space is the same. The motion of the particles is obtained by integrating the gradient of the real phase function from the total wavefunction in the eikonal representation: .

On the right, the graphic shows the squared wavefunction and the trajectories. The left shows the particles' position, the squared wavefunction (blue), the quantum potential (red), and the velocity (green). The velocity and the quantum potential are scaled to fit.