00:01
So first of all, let's see if we can remember high school physics, right, and think about what actual gravity is.
00:06
Actual gravity says that the force exerted by gravity is equal to some constant, a constant of gravitational attraction, times the mass of one, the mass of the second.
00:20
So as each of the countries, the objects gets bigger, there's more force, right? because there's more mass to attract.
00:27
And it's over the distance, right? it attenuates with distance.
00:34
So the gravity model is like replacing the force as the amount of trade, right? it says that the amount of trade, in this case, between, say, u .s.
00:50
And canada, would depend on some constant times, the gdp of canada as representing the size of the country, right? the amount of trade potential depends on the size of the country.
01:04
It also depends on the trading partner, the usa, right? how much, how big the united states is...