English
Related papers

Related papers: Holographic State Complexity from Group Cohomology

200 papers

We introduce the concepts of a symmetry-protected sign problem and symmetry-protected magic to study the complexity of symmetry-protected topological (SPT) phases of matter. In particular, we say a state has a symmetry-protected sign…

Strongly Correlated Electrons · Physics 2021-12-29 Tyler D. Ellison , Kohtaro Kato , Zi-Wen Liu , Timothy H. Hsieh

We demonstrate how to construct the Z2*Z2 global symmetry which protects the ground state degeneracy of cluster states for open boundary conditions. Such a degeneracy ultimately arises because the set of stabilizers do not span a complete…

Quantum Physics · Physics 2014-03-11 Wonmin Son , Luigi Amico , Vlatko Vedral

Symmetry-protected topological (SPT) phases are gapped short-range-entangled quantum phases with a symmetry $G$, which can all be smoothly connected to the trivial product states if we break the symmetry. It has been shown that a large…

Strongly Correlated Electrons · Physics 2014-09-25 Zheng-Cheng Gu , Xiao-Gang Wen

A fundamental problem in quantum information is to describe efficiently multipartite quantum states. An efficient representation in terms of graphs exists for several families of quantum states (graph, cluster, stabilizer states),…

Quantum Physics · Physics 2012-07-04 Radu Ionicioiu , Tim P. Spiller

Conformal order are isotropic and translationary invariant thermal states of a conformal theory with nonzero expectation value of certain operators. While ubiquitous in bottom-up models of holographic CFTs, conformal order states are…

High Energy Physics - Theory · Physics 2023-12-27 Alex Buchel

We reformulate the lifting problem in the D1-D5 CFT as a supercharge cohomology problem, and enumerate BPS states according to the fortuitous/monotone classification. Working in the deformed $T^4$ symmetric orbifold theory, we give precise…

High Energy Physics - Theory · Physics 2026-02-24 Chi-Ming Chang , Ying-Hsuan Lin , Haoyu Zhang

The Kolmogorov complexity of a physical state is the minimal physical resources required to reproduce that state. We define a second quantized quantum Turing machine and use it to define second quantized Kolmogorov complexity. There are two…

Quantum Physics · Physics 2008-04-05 Caroline Rogers , Vlatko Vedral

We make comments on some shortcomings of the non-unitary-invariant and non-bi-invariant complexity in quantum mechanics/field theory and argue that the unitary-invariant and bi-invariant complexity is still a competitive candidate in…

High Energy Physics - Theory · Physics 2019-06-14 Run-Qiu Yang , Yu-Sen An , Chao Niu , Cheng-Yong Zhang , Keun-Young Kim

Physical constraints such as positivity endow the set of quantum states with a rich geometry if the system dimension is greater than two. To shed some light on the complicated structure of the set of quantum states, we consider a…

Quantum Physics · Physics 2007-05-23 S. G. Schirmer , T. Zhang , J. V. Leahy

In an earlier work we developed a holographic theory for the phase transition between bosonic symmetry-protected topological (SPT) states. This paper is a continuation of it. Here we present the holographic theory for fermionic SPT phase…

Strongly Correlated Electrons · Physics 2019-12-12 Lokman Tsui , Yen-Ta Huang , Dung-Hai Lee

We study bosonic symmetry protected topological (SPT) phases with $C_{2}$ rotational symmetry in four spatial dimensions which is not captured by the group cohomology classification. By using the topological crystal approach, we show that…

Strongly Correlated Electrons · Physics 2020-08-19 Sheng-Jie Huang

According to the classification using projective representations of the SO(3) group, there exist two topologically distinct gapped phases in spin-1 chains. The symmetry-protected topological (SPT) phase possesses half-integer projective…

Strongly Correlated Electrons · Physics 2014-01-09 Wei Li , Andreas Weichselbaum , Jan von Delft

I define models of quantum loops and nets which have ground states with topological order. These make possible excited states comprised of deconfined anyons with non-abelian braiding. With the appropriate inner product, these quantum loop…

Statistical Mechanics · Physics 2009-11-13 Paul Fendley

In this work we present some new understanding of topological order, including three main aspects: (1) It was believed that classifying topological orders corresponds to classifying gapped quantum states. We show that such a statement is…

Strongly Correlated Electrons · Physics 2015-06-22 Bei Zeng , Xiao-Gang Wen

The cluster state, the highly entangled state that is the central resource for one-way quantum computing, can be efficiently generated in a variety of physical implementations via global nearest-neighbor interactions. In practice, a…

Quantum Physics · Physics 2008-03-10 Michael C. Garrett , David L. Feder

When an entangled state evolves under local unitaries, the entanglement in the state remains fixed. Here we show the dynamical phase acquired by an entangled state in such a scenario can always be understood as the sum of the dynamical…

Quantum Physics · Physics 2009-11-13 Mark Williamson , Vlatko Vedral

This article is a short introduction to and review of the cluster-state model of quantum computation, in which coherent quantum information processing is accomplished via a sequence of single-qubit measurements applied to a fixed quantum…

Quantum Physics · Physics 2009-11-11 Michael A. Nielsen

Higher-order topological phases (HOTPs) host exotic topological states that go beyond the traditional bulk-boundary correspondence. Up to now, there is still a lack of experimentally measurable momentum-space topological characterization…

Mesoscale and Nanoscale Physics · Physics 2024-12-05 Wei Jia , Bao-Zong Wang , Ming-Jian Gao , Jun-Hong An

Entanglement cohomology assigns a graded cohomology ring to a multipartite pure state, providing homological invariants that are stable under local unitaries and characterize inequivalent patterns of entanglement. In this work we derive…

High Energy Physics - Theory · Physics 2025-12-24 Christian Ferko , Keiichiro Furuya

Finite-dimensional Quantum Mechanics can be geometrically formulated as a proper classical-like Hamiltonian theory in a projective Hilbert space. The description of composite quantum systems within the geometric Hamiltonian framework is…

Mathematical Physics · Physics 2015-12-23 Davide Pastorello