Pith. sign in

Complexity of Mixed States in QFT and Holography

5 Pith papers cite this work. Polarity classification is still indexing.

5 Pith papers citing it
abstract

We study the complexity of Gaussian mixed states in a free scalar field theory using the 'purification complexity'. The latter is defined as the lowest value of the circuit complexity, optimized over all possible purifications of a given mixed state. We argue that the optimal purifications only contain the essential number of ancillary degrees of freedom necessary in order to purify the mixed state. We also introduce the concept of 'mode-by-mode purifications' where each mode in the mixed state is purified separately and examine the extent to which such purifications are optimal. We explore the purification complexity for thermal states of a free scalar QFT in any number of dimensions, and for subregions of the vacuum state in two dimensions. We compare our results to those found using the various holographic proposals for the complexity of subregions. We find a number of qualitative similarities between the two in terms of the structure of divergences and the presence of a volume law. We also examine the 'mutual complexity' in the various cases studied in this paper.

citation-role summary

background 1

citation-polarity summary

years

2026 4 2025 1

roles

background 1

polarities

background 1

representative citing papers

Complexity Inequalities for Quantum Subsystems

hep-th · 2026-06-18 · unverdicted · novelty 7.0 · 2 refs

Defines tripartite complexity and complexity gap for three-subsystem states and reports that the gap has definite sign across holographic CV, Fisher-Rao, and Krylov measures, suggesting it as a building block for complexity inequalities.

Universal Time Evolution of Holographic and Quantum Complexity

hep-th · 2025-07-31 · unverdicted · novelty 7.0

Holographic complexity measures show universal linear growth followed by late-time saturation, proven necessary and sufficient via pole structures in the energy basis using the residue theorem, arising from random matrix statistics.

The Geometry of Quantum Complexity in Open Systems

quant-ph · 2026-07-09 · conditional · novelty 6.0

Open-system quantum complexity is governed by a sub-Finslerian geometry whose curvature depends on the cost penalties for unitary and dissipative controls.

The Entanglement Wedge Polygon

hep-th · 2026-06-19 · conditional · novelty 5.0

The entanglement wedge polygon volume is proposed as a holographic probe of multipartite entanglement; in AdS3 it is topologically quantized, and a mixed-state generalization is constructed.

A Timelike Quantum Focusing Conjecture

hep-th · 2026-04-29 · unverdicted · novelty 5.0

A timelike quantum focusing conjecture implies a complexity-based quantum strong energy condition and a complexity bound analogous to the covariant entropy bound for suitable codimension-0 field theory complexity measures.

citing papers explorer

Showing 5 of 5 citing papers.

  • Complexity Inequalities for Quantum Subsystems hep-th · 2026-06-18 · unverdicted · none · ref 36 · 2 links

    Defines tripartite complexity and complexity gap for three-subsystem states and reports that the gap has definite sign across holographic CV, Fisher-Rao, and Krylov measures, suggesting it as a building block for complexity inequalities.

  • Universal Time Evolution of Holographic and Quantum Complexity hep-th · 2025-07-31 · unverdicted · none · ref 81

    Holographic complexity measures show universal linear growth followed by late-time saturation, proven necessary and sufficient via pole structures in the energy basis using the residue theorem, arising from random matrix statistics.

  • The Geometry of Quantum Complexity in Open Systems quant-ph · 2026-07-09 · conditional · none · ref 47 · internal anchor

    Open-system quantum complexity is governed by a sub-Finslerian geometry whose curvature depends on the cost penalties for unitary and dissipative controls.

  • The Entanglement Wedge Polygon hep-th · 2026-06-19 · conditional · none · ref 60

    The entanglement wedge polygon volume is proposed as a holographic probe of multipartite entanglement; in AdS3 it is topologically quantized, and a mixed-state generalization is constructed.

  • A Timelike Quantum Focusing Conjecture hep-th · 2026-04-29 · unverdicted · none · ref 42

    A timelike quantum focusing conjecture implies a complexity-based quantum strong energy condition and a complexity bound analogous to the covariant entropy bound for suitable codimension-0 field theory complexity measures.