Final answer:
Indistinguishable photons hitting a beam splitter exhibit quantum interference, leading to a probability distribution where they can be reflected or pass through, similarly to the interference observed in Young's double slit experiment.
Step-by-step explanation:
When two indistinguishable photons hit a beam splitter, the outcome is a manifestation of quantum mechanics. When photons encounter a beam splitter, they have the probability of either passing through or being reflected, creating a superposition of states. If we look at a similar experiment, such as Young's double slit experiment, which breaks a single light beam into two sources, we find that interference patterns emerge due to the wave-like behavior of particles like photons and electrons. Each particle, including photons, passes through both slits and interferes with itself to build up an interference pattern - suggesting a probability distribution for where the particle will eventually be detected. In a beam splitter scenario, even if there is one photon at a time, we would observe a similar interference effect because each photon could take either path, leading to a probability distribution for its final position.