I am looking into the correction now.
If memory serves (HA), back in the Mesozoic Era, we just took an OG and an FG, using a primitive hydrometer, and thought we were finished. I must be right about compensation being a recently developed concept, because online, I see people trying to figure things out almost a decade after I quit brewing.
Hard as it may be to believe, I am not a total idiot about physics. I have a degree and a couple of years in grad school. When you brought up compensation, I figured it had to be really simple, but it looks like it's not, because no simple physics problem survived the 17th century. Nobody was arguing about simple problems in 2015. I assume a differential equation is used here, and I have no idea what that equation is or what goes into it. If it's not a differential equation, somebody must have done a bunch of measurements and made an equation up from them. I guess.
Since I am not likely to understand this without studying it for hours, and maybe not even then, I am going to take your helpful advice and use online calculators.
Unbelievably, I didn't do a good job taking notes when I brewed. I was determined to be a good lab student, but you know what Mike Tyson says: "Everyone has a plan until they get punched in the mouth."
Things were burning and spilling, and the machine was giving me error warnings, so I was a little rushed. I did not write down the original Brix reading. I converted to SG and used that. I feel positive it was 13.2, and I got 1.054 from that using a chart, but now I see sources saying it's really 1.052.
The calculator you sent me to says I now have a gravity of 1.007, which is 17 points lower than I thought. I don't know if that can be right after such a short fermentation. I was expecting 1.010 from 1.057, though, so 1.007 looks reasonable for 1.052.
If things are this far along, I need to seal the bucket and wait for my kegs. There should be no danger of pressure building up now.