First, Einstein’s birthday: March 14, 1879. Do you ever use a GPS? Then you are indebtted to Einstein for the Relativistic Time Dilation equation.
Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion .
I won’t include the equation, since it won’t add anything. You can find it in many places on the web.
And it is Pi day. π = 3.1415926535… (That is 10 digits, and enough for most applications.)
The video is “A Brief History of Pi.” It is a bit long at just over 16 minutes, but the videos either are just short and entertaining but don’t really explain anything, or they jump into some fairly stiff mathematics and would lose everyone. Go get some pie, and coffee, and enjoy learning a bit of history, and maybe even a bit of math. It won’t hurt, I promise. (Well, maybe for a minute.)