What the study found
The authors report a causality-based divide-and-conquer algorithm for nonequilibrium Green’s function calculations with quantics tensor trains. They say it can extend the simulated time domain stably and efficiently by using the causality of Green’s functions.
Why the authors say this matters
The study suggests this is useful for long-time simulations in nonequilibrium dynamical mean-field theory, especially for quench dynamics in symmetry-broken phases where slow relaxation can require extended time windows. The authors conclude that the method can extend the simulated time domain without a significant increase in the cost of storing the Green’s function.
What the researchers tested
The researchers developed a divide-and-conquer algorithm based on causality and applied it within nonequilibrium dynamical mean-field theory. They used it for simulations of quench dynamics in symmetry-broken phases, using quantics tensor trains to represent the Green’s function.
What worked and what didn't
The algorithm allowed the simulated time domain to be extended. The abstract states that this was done without a significant increase in the storage cost of the Green’s function. No negative results are described in the available summary.
What to keep in mind
The abstract does not describe detailed limitations, quantitative benchmarks, or comparisons with other methods. It also does not provide numerical performance values beyond the statement about storage cost.
Key points
- The paper proposes a causality-based divide-and-conquer algorithm for nonequilibrium Green’s function calculations.
- The method is paired with quantics tensor trains, a compact way to represent the Green’s function.
- The authors say the approach extends the simulated time domain stably and efficiently.
- They apply the method to quench dynamics in symmetry-broken phases within nonequilibrium dynamical mean-field theory.
- The abstract says the extended time domain does not come with a significant increase in Green’s function storage cost.
Disclosure
- Research title:
- Causality-based algorithm extends nonequilibrium Green’s function time simulations
- Authors:
- Ken Inayoshi, M. Środa, Anna Kauch, Philipp Werner, Hiroshi Shinaoka
- Institutions:
- Saitama University, University of Fribourg, TU Wien
- Publication date:
- 2026-03-09
- OpenAlex record:
- View
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