# Quantum ether: photons and electrons from a rotor model

@article{Levin2006QuantumEP, title={Quantum ether: photons and electrons from a rotor model}, author={Michael Levin and Xiao-Gang Wen}, journal={Physical Review B}, year={2006}, volume={73}, pages={035122} }

We give an example of a purely bosonic model--a rotor model on the 3D cubic lattice--whose low energy excitations behave like massless U(1) gauge bosons and massless Dirac fermions. This model can be viewed as a ''quantum ether;'' a medium that gives rise to both photons and electrons. It illustrates a general mechanism for the emergence of gauge bosons and fermions known as ''string-net condensation.'' Other, more complex, string-net condensed models can have excitations that behave like…

## 56 Citations

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## References

SHOWING 1-10 OF 17 REFERENCES

Colloquium: Photons and electrons as emergent phenomena

- Physics
- 2005

Recent advances in condensed-matter theory have revealed that new and exotic phases of matter can exist in spin models (or more precisely, local bosonic models) via a simple physical mechanism, known…

Quantum order from string net condensations and origin of light and massless fermions

- Physics
- 2003

Recently, it was pointed out that quantum orders and the associated projective symmetry groups can produce and protect massless gauge bosons and massless fermions in local bosonic models. In this…

Origin of gauge bosons from strong quantum correlations.

- Physics, MedicinePhysical review letters
- 2002

Through models, it is shown that the existence of light can simply be a phenomenon of quantum coherence in a system with many degrees of freedom.

Fermions, strings, and gauge fields in lattice spin models

- Physics
- 2003

We investigate the general properties of lattice spin models with emerging fermionic excitations. We argue that fermions always come in pairs and their creation operator always has a stringlike…

String-net condensation: A physical mechanism for topological phases

- Physics
- 2005

We show that quantum systems of extended objects naturally give rise to a large class of exotic phases---namely topological phases. These phases occur when extended objects, called ``string-nets,''…

Quantum Field Theory of Many-body Systems: From the Origin of Sound to an Origin of Light and Electrons

- Physics
- 2004

1. Introduction 2. Path integral formulation of quantum mechanics 3. Interacting boson systems 4. Free fermion systems 5. Interacting fermion systems 6. Quantum gauge theories 7. Theory of quantum…

Hamiltonian Formulation of Wilson's Lattice Gauge Theories

- Physics
- 1975

Wilson's lattice gauge model is presented as a canonical Hamiltonian theory. The structure of the model is reduced to the interactions of an infinite collection of coupled rigid rotators. The…

Artificial light and quantum order in systems of screened dipoles

- Physics
- 2003

The origin of light is an unsolved mystery in nature. Recently, it was suggested that light may originate from a new kind of order, quantum order. To test this idea in experiments, we study systems…

Pyrochlore photons: The U ( 1 ) spin liquid in a S = 1 2 three-dimensional frustrated magnet

- Physics
- 2004

We study the $S=1/2$ Heisenberg antiferromagnet on the pyrochlore lattice in the limit of strong easy-axis exchange anisotropy. We find, using only standard techniques of degenerate perturbation…

Topological Order and Conformal Quantum Critical Points

- Physics
- 2003

Abstract We discuss a certain class of two-dimensional quantum systems which exhibit conventional order and topological order, as well as quantum critical points separating these phases. All of the…