There are alternative sets of postulates which yield entirely equivalent results for several important theories. In such cases the choice of a particular set of postulates may be based upon mathematical simplicity, close relationship to experiments or to the nature of the theory, or merely personal taste. While the postulate of conservation of energy is usually presented in similar form for the...

Investment is often irreversible: once installed, capital has little or no value unless used in production. This paper proposes, solves and characterizes a model of sequential irreversible investment by a firm facing uncertainty in technology, demand and price of capital. The solution can be found in closed form if simple (but not totally unrealistic) functional forms are assumed, and can be gi...