#### Numerical methods package in C++

I still code in my spare time and for a while I’ve been gathering some numerical methods I did at university in an easy-to-understand generic C++ package. Despite being easy to understand, I also tried to implement the best method I knew for each problem.

The root finding algorithm is based on Brent’s method which is, in turn, based on the secant method. If everything fails, it throws an exception and you can use the safe bisection method.

The integration is using the Romberg’s method, which is a further extrapolations of Simpson’s method which is already much better than the trapezoid basic method.

For Interpolation I’m using the Natural Cubic Spline but would like to implement other types of splines (like complete, periodical, clamped etc). The interpolation is working, but I couldn’t managed to get the coefficients right yet.

Other codes I have are Monte Carlo, Runge-Kutta and Markov Chain (this one using boost graph library for C++) and will be integrated soon. I’ll let you know when it’s done.

#### Book: Flat and Curved Space Times

The first time I read this book was during my special relativity course at university. I couldn’t understand a thing the teacher was saying (probably because his explanations were always: “you won’t be able to understand that”) and I needed to replace a 35% grade I got in the first exam to complete the course.

Well, hopeless as I was, headed to the library in search of a magical book (other classmates were helpless as well) and found this one. The magic in it is that, instead of trying to force the Lorentz transformations down the throat first and then explain the basic principles of relativity, it does it by simply showing the topology of the space and assuming that the speed of light is constant (pretty much the same path Einstein took in the first place).

So, the first chapter has no equations whatsoever, only graphics with light waves going back and forth and he derives the light-cones automagically from it, what happens to the “world” at high speeds and how does it affect our senses of reality. It goes on for all kinematic principles only using Newton equations and gamma. Lorentz transformations only appear in the fourth chapter.

After that, not only I could understand relativity as a whole, but I also got 90% grade on the final exam! It’s an old (88) book but time has no meaning for a very good book, especially for a subject that hasn’t changed that much in the last decades.

I recommend it to physics-wannabe as well as lay people with little background in math, and if your teacher is as hopeless as mine was, ignore him and read this book.