Interacting boson problems are QMA-hard

Understand

Computing the ground-state energy of interacting electron (fermion) problems has recently been shown to be hard for QMA, a quantum analogue of the complexity class NP.

• Fermionic problems are usually hard, a phenomenon widely attributed to the so-called sign problem occurring in Quantum Monte Carlo simulations.
• The corresponding bosonic problems are, according to conventional wisdom, tractable.
• Here, we discuss the complexity of interacting boson problems and show that they are also QMA-hard.