Simulating the Φ4 theory on a quantum computer
In [1] and [2], algorithms for simulating lattice Φ4 scalar field lattice on a quantum computer was introduced. This can serve as a first example of simulating general lattice field theory on quantum computers.
The Hamiltonian under consideration is given by:
H(Φ,Π)=21Π2+21m2Φ2+21(∇Φ)2+4!λΦ4+JΦ.
Here Φ and Π satisfy the commutation relation:
[Φ(x),Π(y)]=iδ(x−y)
To simulate it on a quantum computer, we need to discretize it so that the lattice Hamiltonian takes the form:
Hlat=aD∑j=1N(21Πj2+21m2Φj2