  We investigate the violation of the Leggett-Garg inequalities for a quantum
field, focusing on the two-time quasi-probability distribution function of the
dichotomic variable with a coarse-grained scalar field. The Leggett-Garg
inequalities are violated depending on the quantum state of the field and the
size of coarse-graining. We also demonstrate that the violation of the
Leggett-Garg inequalities appears even for the vacuum state and the squeezed
state by properly constructing the dichotomic variable and the projection
operator.
