Quantum Mechanics/Grand Unification?

Failed to parse (lexing error): xmlns="http://www.w3.org/1998/Math/MathML"><mo>&int;</mo><mmultiscripts><mrow><mspace width="mediummathspace" height="0.2em" /><mi>In</mi><mspace width="mediummathspace" height="0.2em" /><mi>e</mi><mspace width="mediummathspace" height="0.2em" /><mspace width="mediummathspace" height="0.2em" /><mi>de</mi><mspace width="mediummathspace" height="0.2em" /><mspace width="mediummathspace" height="0.2em" /><mo>&equals;</mo><mspace width="mediummathspace" height="0.2em" /><mn>1</mn></mrow><mprescripts /><mrow><mn>1</mn></mrow><mrow><mi>e</mi></mrow></mmultiscripts>