Exhaustion functions and Stein neighborhoods for smooth pseudoconvex domains

Limits of multivariable functions describe how a function behaves as its input approaches a particular point in the plane. In single-variable calculus, a limit examines the behavior of a function as the input approaches a number from two directions along a line. For functions of two variables, the situation is more complex because the input can approach a point from infinitely many paths in the xy-plane. A limit exists only when the function approaches the same value along every possible...

A state function is a thermodynamic property that depends solely on the current state of a system, irrespective of its history or how it arrived at that state. These functions are represented by capital letters, such as U, H, and S, which stand for internal energy, enthalpy, and entropy, respectively.For instance, the value of internal energy depends on the system's state variables and remains unaffected by the process path. This means that whether the system underwent a linear process or a...

The shape of a suspension bridge cable hanging under its own weight is described by a catenary curve, which is modeled using the hyperbolic cosine function. This mathematical model accurately captures the balance between gravity and tension acting along the cable. When a particular vertical position on the cable is known, the corresponding horizontal position can be determined using the inverse hyperbolic cosine function, allowing for a detailed analysis of the cable's geometry.Inverse...

A multivariable function assigns a single output value to each ordered set of independent inputs, thereby defining a surface in three-dimensional space. For a function f(x, y), each point (x, y) corresponds to a height z = f(x, y). This geometric interpretation allows systematic analysis of how the output varies as multiple variables change simultaneously. Such functions frequently arise in physical models and optimization problems, where system behavior depends on several interacting...

Piecewise defined functions are mathematical models where different expressions define a function over distinct intervals of the domain. These functions are useful for representing systems with varying behaviors depending on input values.For example, the function:  uses a linear rule for inputs less than or equal to –1 and a quadratic rule for values greater than –1. Although it has two formulas, it still defines a single function.Another common type is the absolute value function, given...

An arched gate can be effectively modeled using a hyperbolic cosine profile because this type of function is smooth and symmetric about the vertical axis. When the arch is centered at the origin, its maximum height occurs at the center point. This symmetry ensures that any height below the crown of the arch is reached at two horizontal positions that are equal in distance from the centerline but lie on opposite sides.To determine where the gate reaches a height of five meters, the height of the...