If yes, could the same photon hit multiple targets as it expands? If not, how does the photon acquire the wave-ness if it is not born as a spherical wave? Also, in second case, how can multiple photons synchronize to make up a single wave front?
Answer
The only way to induce electromagnetic radiation is to disturb subatomic particles. For the emission of a photon it's enough that in an atom an (excited) electron falls back into a lower level. Once emitted the photon travels through empty space as a quanta of energy. The photon is indivisible during its travel. Hence a single photon couldn't have a spherical wavefront.
The sum of the emitted photons - say from an electric bulb - is called electromagnetic radiation. The emission from a laser is very strong directed, from a bulb it is much more spherical directed. So the radiation could be spherical, no matter would this be from a bulb or a star. Being far enough away from the source one would receive single photons. But this is not a wavefront.
how does the photon acquire the wave-ness?
A wavefront one could produce with radiation waves. Radio waves are produced by periodical acceleration of electrons in the antenna rod.
how can multiple photons synchronize to make up a single wave front?
Since this acceleration happens nearly synchronously for all involved electrons the number of emitted photons follows the frequency of the antenna generator. So for radio waves one really could measure wave properties (which is not possible for a bulb powered by a DC current). But again, being far enough from the antenna one will receive single photons.
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