Saved in:
| Main Authors: | , |
|---|---|
| Format: | Preprint |
| Published: |
2026
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2601.00259 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866911350047899648 |
|---|---|
| author | Shukla, Rohit Kumar Levy, Amikam |
| author_facet | Shukla, Rohit Kumar Levy, Amikam |
| contents | Quasiprobability distributions capture aspects of quantum dynamics that have no classical counterpart, yet the dynamical emergence of their negativity in many-body systems remains largely unexplored. We introduce the \emph{first-time negativity} (FTN) of the Margenau-Hill quasiprobability as a dynamical indicator of when local measurement sequences in an interacting quantum system begin to exhibit genuinely nonclassical behavior. Using the Ising chain, we show that FTN discriminates clearly between interaction-dominated and field-dominated regimes, is systematically reshaped by temperature, and responds sensitively to the breaking of integrability. When measurements are performed on different sites, FTN reveals a characteristic spatio-temporal structure that reflects the finite-time spreading of operator incompatibility across the lattice. We further compare the numerical onset of negativity with a recently proposed quantum speed limit (QSL) for quasiprobabilities, which provides a geometric benchmark for the observed dynamics. Our results identify FTN as a practical and experimentally accessible probe of real-time quantum coherence and contextuality, directly suited to current platforms capable of sequential weak and strong measurements. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2601_00259 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | First appearance of quasiprobability negativity in quantum many-body dynamics Shukla, Rohit Kumar Levy, Amikam Quantum Physics Quasiprobability distributions capture aspects of quantum dynamics that have no classical counterpart, yet the dynamical emergence of their negativity in many-body systems remains largely unexplored. We introduce the \emph{first-time negativity} (FTN) of the Margenau-Hill quasiprobability as a dynamical indicator of when local measurement sequences in an interacting quantum system begin to exhibit genuinely nonclassical behavior. Using the Ising chain, we show that FTN discriminates clearly between interaction-dominated and field-dominated regimes, is systematically reshaped by temperature, and responds sensitively to the breaking of integrability. When measurements are performed on different sites, FTN reveals a characteristic spatio-temporal structure that reflects the finite-time spreading of operator incompatibility across the lattice. We further compare the numerical onset of negativity with a recently proposed quantum speed limit (QSL) for quasiprobabilities, which provides a geometric benchmark for the observed dynamics. Our results identify FTN as a practical and experimentally accessible probe of real-time quantum coherence and contextuality, directly suited to current platforms capable of sequential weak and strong measurements. |
| title | First appearance of quasiprobability negativity in quantum many-body dynamics |
| topic | Quantum Physics |
| url | https://arxiv.org/abs/2601.00259 |