  The idea of this paper comes from the famous remark of Piketty and Zuckman:
"It is natural to imagine that $\sigma$ was much less than one in the
eighteenth and nineteenth centuries and became larger than one in the twentieth
and twenty-first centuries. One expects a higher elasticity of substitution in
high-tech economies where there are lots of alternative uses and forms for
capital." The main aim of this paper is to prove the existence of a production
function of variable elasticity of substitution with values greater than one.
