17.1 Introduction

In this chapter the dynamics of scalar multi-mode quantum fields is considered. It examines a quantized field which can have photons in various states (see). Some theoretical basics are stated in Part II.

Each field of class is described by the next states parameters:

• _fockState (vector) is a multi-mode state of the field with numbers n ₁ ? n _k ? = { n ?}

• _eigValFockState (vector) are eigenvalues of states

• _nmbCurrentStatethe (int) is a number of the current state

• _sTitleOfState (String) is the name of the current state (String)

• _sTitleOfQuantField (String) is the name of the given field (String, this parameter is convenient while working with several fields)

Functions:

• the operators of construction of a vacuum field with a given number of states and, possible, the name, (various constructors TQuantField)

• the operators of construction of a copy of given vacuum field (overloading operator = ),

• the operators of creations (aX is a ⁺) and annihilations (a) of photons,

• set/get are various functions to access and modify the state parameters of the field,

• the operators of summation or subtraction of the fields states (overloading + and ? operators)

• toString is function to obtain the information on the current state of the field.

In Fig. 17.1 the result of output of this program is shown. At first the vacuum field with six empty states is constructed. (We remind that in C++ the arrays indexes are counted from 0.) The name of this...