According to the standard interpretation of quantum mechanics, the wavefunction of a photon is nonlocal. The wavefunction describes the probability distribution of finding a particle, such as a photon, in different states or locations. In quantum mechanics, the wavefunction can exhibit nonlocal correlations, meaning that the state of one particle can be entangled with the state of another particle, regardless of the spatial separation between them.
This nonlocality is a fundamental feature of quantum mechanics and is often referred to as "quantum entanglement." It implies that the wavefunction of a photon is not confined to a specific location but can be entangled with the wavefunction of another particle, even if they are spatially separated. The entangled particles may exhibit instantaneous correlations, known as "spooky action at a distance," which cannot be explained by classical physics.
It's important to note that the wavefunction itself is a mathematical representation and does not have a direct physical interpretation. However, its nonlocal nature is evident in the experimental results of various quantum phenomena, including entanglement experiments.