New directions in Gromov-Witten theory

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Gromov-Witten invariants are important in String Theory, the physical theory according to which elementary particles are tiny strings, instead of points, as was believed since Newton. String theory is the best candidate for the so-called Theory of Everything, which  unifies all physical theories, in particular Einstein's theory of relativity and the quantum field theory.Recently it was discovered that Gromov-Witten invariants are related to the so-called Donaldson-Thomas invariants.  This is connection is, in fact, still a conjecture, but it is very important, because Donaldson-Thomas invariants can explain many strange phenomena exhibited by Gromov-Witten invariants.In my recent research I discovered something surprising about Donaldson-Thomas invariants. They behave like Euler characteristics.  The Euler characteristic of a shape is a number which does not change, if the shape is deformed as if it was made of rubber.  The surface of a sphere, for example, has Euler characteristic 2.  The surface of a donut shape has Euler characteristic 0. The fact that Donaldson-Thomas invariants are certain kinds of Euler characteristics has important consequences, also for Gromov-Witten invariants and hence for String Theory.The goal for the future is to understand these Euler characteristics more deeply and make them a more flexible tool.  They should not just be numbers, but some more complicated structure.  Numbers are for counting things, but the things are lost in the process.  I will discover the "things" which are "counted" by the Euler characteristics which give rise to Donaldson-Thomas invariants.