Lu Zhou's flight to China was after Christmas.
He had three days before his flight, and he planned to run some errands. This was to prevent him from being swamped when he returned back to Princeton after the break.
The first matter he had to deal with was the "existence of a smooth solution to three-dimensional incompressible Navier-Stokes equation" research project.
Other than the plasma turbulence phenomenon, this was Lu Zhou's most important research project.
There had only been one discussion meeting ever since the "NS research project group" was established.
The next day, Lu Zhou went to Nassau Hall to hand in his holiday application. He then went to the Department of Mathematics building at Princeton University where he found Professor Fefferman's office.
When he arrived, Professor Fefferman was talking about next month's American Mathematical Society Conference with his students.