The Doctor is most likely one of the main characters. There could also be his companions, though without more specific knowledge about this short story, it's hard to say exactly who else.
The story might be about the Doctor facing some kind of threat related to a 'ghost in the machine'. It could involve a computer or technological system that has an unexpected and perhaps malevolent presence within it, like a digital entity that is causing trouble or mystery.
There are likely multiple novels that might have the 'ghost in the machine' concept incorporated. Without more context about the particular 'ghost in the machine novel' in question, we can't accurately name the author. It could be from a new or emerging writer exploring the mind - body relationship in a unique way, or it could be a reimagining of an old concept by an established author. To find the author, more information about the specific book is needed.
I don't have enough information to determine the main characters. It could be a scientist who invents or studies the machine, a curious child who stumbles upon it, or a group of adventurers who are on a quest related to the machine.
The main character is the Time Traveller. He's the one who builds the time machine and goes on the journey through time. Then there are the Eloi and the Morlocks. The Eloi are the gentle, child - like beings in the future, and the Morlocks are the more menacing, subterranean creatures.
There's also the emperor. He is a very important character as he represents the power and the establishment. His reaction to the flying machine is crucial in driving the story forward. When he sees the flying machine, he has to decide what to do about this new and potentially dangerous thing in his kingdom.
Since I'm not familiar with this particular graphic novel, it's hard to say for sure. However, in a story with such a title, we might expect a character who represents the human side of things, perhaps a scientist or an engineer. There could also be a character that embodies the 'ghost' in some way, whether it's an AI with a mind of its own or a strange, otherworldly being that has become part of the machine. And there might be a supporting character, like a friend or a mentor, who helps the main character in their quest to understand what's going on.