In physics, there are constants defined to 10+ decimal places. Most economic debates are about the sign: is Coke riskier than GM stock? Does increasing the minimum wage increase aggregate worker total wage, or reduce it? Would increasing government spending increase or decrease GDP over the next 5 years?
Consider the following example, from Shane Frederick's
presentation on time discounting at MIT. This is the estimate of the spped of light over the past 150 years or so:
In contrast, below are a set of estimates of an important parameter in economics, the time discount parameter. If delta =1, you count the future equal to today, and are indifferent to receiving a massage in 1 year or tomorrow. If you have a delta=0, you totally ignore the future, and so glue sniffing is optimal, because though it kills your brain cells, it is a great rush over the next 5 minutes (or however long glue-sniffing highs last).
Note even at first, the estimates of the speed of light were reasonably close to the true value (or, the current value), off by about 0.07%, and converged to the current estimate about 50 years ago. In contrast, estimates for the discount factor seem to be a random draw from the uniform distribution between 0 and 1, though slightly more between 0.9 and 1.0.
So, the equations in advanced economics and physics look the same, but that's a pretty superficial similarity