It’s 3.14. Pi Day. And Einstein’s birthday. And we’ll be celebrating around here shortly. This is a re-post from 2013, because this year’s pie is still in the mixing bowl, and-anyway, I already used up all my vast physics knowledge last year. Ya’ll have a great pi day!
OK, I have a basic physics lesson for you that explains quite simply what pi and Einstein and winter squash pie have in common. Since I have successfully avoided most things physics and pretty much all things math during my lifetime, I have consulted with my three scientist offspring about today’s topic. Rita, who studies nursing at Emory U in Atlanta, says to ask Wes. Annie, who is a medical physicist, says to ask Wes. And that pi has to do with Einstein’s Field Equation of Relativity which looks like this:
Wes is a billion floors down in the atomic, molecular, optical physics lab at Kansas State U. where he shoots electrons with a laser and then makes up stuff about why they land where they land. Evidently he’s busy, so I will just fill in the blanks for you about what Einstein had in mind with his equation, that I’ll call “Rik” for short.
When Einstein was about 2, he let go of his ball and became obsessed with why it went down instead of up. Or maybe that was Richard Feynman. Anyway, when Einstein was about 9, he was struck out at a little league game because he was preoccupied with calculating the trajectory of the ball as it traveled toward him through the curve of spacetime. He used pi to calculate the curve. Of course. Well, he got benched after that and he had time to think about electromagnetic fields and linear momentum and stuff like that, and some of these things had something to do with pi. And then, as he was spacing out on the bench, his stomach started growling which reminded him about how a particle of pie would be so nice about now. So as he was walking home to get that piece of pie, he whipped up the geodesic equation which expains how if you drop an electron, it will not go straight down, it will go in the straightest possible line on the curve of spacetime and it will end up in Wes’ lab and he will zap it with a laser as soon as he finishes eating his pumpkin pie.
I think that about covers it, don’t you? Except for calculating the circumference of a 9-inch pie plate. You do that while I tell you about Mrs. Painter’s winter squash/pumpkin pie.
First you roast a medium winter squash until tender. I had one last red kuri squash from the fall farmer’s market. When it’s roasted, skin your squash and puree it in the food processor until smooth. Drain by placing in a mesh sieve if it seems liquidy.
Then you add your other pie ingredients and whisk. Pour the mixture into a 9 inch pie plate that’s been fitted with a crimped, flaky butter pie crust that you’ve made and then bake it as per the “directions” below. Cut out and bake your pie crust numbers and letters and bake them separately at 400 degrees.
Are you finished calculating the circumference of that pie plate? Do let me know what you come up with!
Mrs. Painter’s Pumpkin Pi for 9-inch pie plate and 63.617 square inches of filling
2 cups baked, drained (if necessary) and pureed winter squash/pumpkin or sweet potato
1 cup evaporated milk
1 large egg
3/4 cup not-packed brown sugar (should equal to about 1/2 cup packed)
1 Tbs. flour pinch salt 1 tsp. each of cinnamon and ginger
Grating of fresh nutmeg
Whisk those ingredients well and pour into an unbaked, crimped, and chilled 9-inch HOMEMADE pie crust. Oh for heaven’s sake, don’t even think about inviting Pillsbury pre-made pie crust to this party! Place the pie on the bottom shelf (gas oven) or lower third (electric oven) in a preheated 425 oven. Immediately turn the oven down to 400. In 15 minutes, turn the oven down to 350 and bake for 30 minutes more until it’s set in the middle and the crust is nicely browned. It should still jiggle a tad.
For the pie crust numbers: Wilton makes a letters/numbers cut-out set, which you can find in your local craft store. Roll out dough scraps or about 1/4 of a recipe of pie crust and freeze on a cookie sheet. Cut the letters out while frozen, and bake at 400 for a few minutes until lightly browned. DO NOT leave the stove and burn pi!