Fortran has a special place in numerical programming. You can certainly make good and fast software in other languages, but Fortran keeps performing very well despite its age. Moreover, it's easier to make fast programs in Fortran. I've made fast programs in C++, but you have to be more careful about things like pointer aliasing. So, there has to be a reason for this, and a very technical one. Is it because the compiler can optimize more? I would really like to know technical details, so if I use another language I can take these things into consideration.
For example, I know -or so I think- that one thing is that the standard specifies that pointers are contiguous in memory always which means faster memory access. I believe you can do this in C++ by giving a flag to the compiler. In this way it helps to know what Fortran does good, so that if using another language we can imitate this.