Well, it might be about self - discovery. The silence in the city could force the characters to look inward. Without the distractions of a noisy world, they have to confront their true selves, face their fears and desires, which is a common theme in many short stories.
I think it could be the theme of change. The city being silent might be a symbol of a stagnant state at first. But as the story progresses, the characters' experiences within this silent city may lead to some sort of transformation, either in their beliefs, relationships or personal growth.
The main theme could be mystery. The 'white city' might hold secrets that are only revealed through the silence, perhaps related to its past or the people who once inhabited it.
The main theme could be isolation. In the story, characters might be physically or emotionally alone, and the 'sound of silence' represents that state of being apart from others.
The main theme could be redemption. Often in such stories, a character emerges from a state of silence, which might symbolize a past of pain or isolation, and through their journey, they seek to redeem themselves or find a new purpose in life.
One of the main themes is the power dynamic. We see the relationship between Clarice Starling, the trainee, and Hannibal Lecter, the brilliant and deranged psychiatrist. Their interactions show how knowledge and manipulation play out in different power scenarios. Also, the theme of transformation is present as Starling grows and changes throughout her encounters with Lecter and the serial killer case she's on.
The main theme might be about finding meaning in solitude or the power of inner peace in a silent world.
Perhaps there is a local inhabitant in the city. This character might be used to show the contrast between those who have always been in the silent environment and those who are new to it. The local could have unique ways of living and thinking that the new arrivals find puzzling or fascinating.
The theme could be about the power of silence and its impact on characters or the exploration of inner thoughts during quiet moments.
The theme could be exploration of the human mind in quietude. The story's plot could detail the character's emotional journey, the lessons they learn, and how this year of silence changes their outlook on life. There might be moments of doubt, breakthroughs, and a gradual evolution of their personality.
Again, not knowing the specific 'Silence a novel', it could be about many things. It might be about the silence in a person's inner world, or perhaps the silence in a particular society or community.
The main theme could be about mystery. In many short stories set in a 'black city', mystery often prevails as the setting itself is rather gloomy and can hide many secrets.