Backreaction I: The Torus
  We use wrapped D-brane probes to measure position dependent perturbations of compactification moduli. Due to the backreaction of the D-branes on the local geometry, we suspect that measuring the fluctuations of one modulus to high precision will generically affect the others. These considerations lead us to conjecture a novel uncertainty principle on the Calabi-Yau moduli space. We begin our investigation with a gedanken experiment on a torus. 
Jarah Evslin, Uday Varadarajan and John E. Wang