erottettavuus

Erottettavuus, also known as separability, is a concept in physics and mathematics that describes the ability of a system to be divided into independent subsystems. In quantum mechanics, for example, a separable state is one that can be expressed as a tensor product of the states of its constituent parts. This means that the state of the whole system can be fully described by the states of its individual components, and there are no correlations between them.

The concept of separability is closely related to entanglement, which is a phenomenon where the state of one part of a system cannot be described independently of the state of another part. In contrast, a separable state is one where the subsystems are not entangled, and their states can be described independently.

In classical physics, the concept of separability is more straightforward. For example, in a system of two particles, if the position and momentum of one particle do not depend on the position and momentum of the other, then the system is separable.

The study of separability is important in various fields, including quantum information theory, where it is used to understand the properties of quantum states and the limits of quantum communication and computation. In statistical mechanics, separability is used to study the behavior of complex systems and to understand phase transitions.