"Margaret."
The room turned. Sullivan looked up.
"I think we should pause this demonstration."
Walsh stood up immediately. "Dr. Whitmore, with respect—"
"Margaret, please come look at this."
Sullivan crossed the room. She did not look at Walsh; she did not look at Whitney. She walked to the back row and stopped in front of Whitmore's seat. Whitmore handed her the journal, already open, the corner of the page folded.
Sullivan looked at the page. She read for ten seconds, then read it again. Her face went still in a particular way—the stillness of someone who has just understood something they cannot un-understand.
She looked up. She looked at Walsh.
"Edward, where did you say this problem came from?"
Walsh's voice rose. "Margaret, that is irrelevant—"
"Edward."
"It is a private extension of Professor Vandenberg's unpublished work! I have already explained—"
"Edward, the problem on that blackboard appears to be a direct transformation of a result published three months ago in the Journal of Number Theory." She paused. "By W. Tate."
The room went silent. Walsh's mouth opened, then closed, then opened again.