The quickest path for light is the straightest line through the void, where nothing bends or scatters it. Think of the emptiness between stars as a silent river—no wind, no stones. If you want to make it a little faster, you can let gravity act as a guide, like a subtle current that pulls the photon along a curved, but still short, route. In short, let the space itself whisper its shortest whisper and the photon will follow.