Albert Einstein is introduced at the beginning of the novel as a weary patent clerk working nonstop on his scientific theory of time. Although the reader only catches glimpses of him in the novel's Interludes, his dreams reveal he is as imaginative as he is scientifically brilliant. In the Interludes his good friend Michele Besso depicts him as quiet, aloof, and distracted, though deeply caring and devoted. The character of Albert Einstein in Einstein's Dreams is based on the real physicist, but the reader is aware that this is a fictional envisioning of him. The author uses him as an inspiration to imagine the ways in which dreams and science might intersect to create new innovations.
The author reveals Michele Besso only throughout the novel's brief Interludes, which are narrated from his perspective. His worries about his good friend Albert Einstein show Besso to be a caring, engaged friend who is also a good husband to his wife. Michele Besso is based on the real-life close friend of Albert Einstein by the same name. The real Michele Besso also acted as a sounding board and confidant for Albert Einstein, and in the novel he functions as a separate lens through which to view the fictional Einstein in his waking world.
The Dream Figures are featured throughout the novel's dream vignettes. Purposely left nameless, they stand for humanity as a whole and depict the different ways in which people relate to time. Their relationships, sorrows, hopes, and fears figure heavily in each vignette, showing the common human experience. Rather than follow each character through a beginning, middle, and end of a complete story, the reader is meant to view the Dream Figures as a collective. Even though they are nameless and appear and reappear randomly, Lighman makes it easy for the reader to identify with their hopes and fears regarding the ways in which time impacts their lives. They provide the human connection and identification that is necessary to humanize Einstein's abstract and scientific concepts of time.
Anna Besso seems to be happily married to Michele, although the couple appears to be childless. She enjoys cooking dinner for Albert and Michele, and the domestic scene is peaceful and harmonious. The real Michele Besso's wife's name was actually Anna.
Mileva Einstein does not appear to be very happily married, and Einstein refers more than once to what seems like a dysfunctional marriage. He prefers to avoid Mileva, preferring the company of the Bessos, for example—to the point where Mileva comes to their home with their infant son to get Einstein to return to his own home.