It's the beta version of Einstein's law of relativity.
I say to Sue that I'll be down in five minutes, but she claims I actually took an hour. The reason for this is my proximity to the CPU, where the electrons are buzzing about at a rate of knots. This has the effect of slowing time in the vicinity and, as a result, five minutes of computer time is equivalent to an hour of 'earth time'. Of course, I am unable to prove this to Sue as, by the time she challenges me, I have turned off my machine and all clocks have adjusted to local time.
Don't you have a po-faced smiley??