hi,i don't understand this slide,https://www.sas.upenn.edu/~jesusfv/Continuous_Time_1.pdf.have no clue.but i do want to learn continuous time in macroeconomics,wonder you could help? there are 5 slides link under continuous time in macroeconomics https://www.sas.upenn.edu/~jesusfv/ i really appreciate it if you could help.i'm trying to learn measure theory,optimal control,stochastic process,differential equation,but find them really hard to understand just read books,many notations can't understand