Wave function of string and membrane and spacetime geometry
  A first-quantized string (and membrane) theory is developed here by using a general wave function of the string (and membrane), analogously to the first-quantized quantum theory of a point particle. From the general wave function of the string (and membrane), the properties of the string (and membrane) such as its relation to Bosons, Fermions and spacetime are investigated. The string and membrane wave functions are found to be very useful and we can deduce Klein-Gordon equation, Dirac equation and the fundamental property of the spacetime from this new starting point. 
Hongwei Xiong, Shujuan Liu