REVIEW 4 major objections 4 minor 48 references
A single fixed chaotic Hamiltonian, with two Pauli insertions at random times, generates approximate unitary k-designs—no quenches or Hamiltonian ensembles needed.
Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →
T0 review · deepseek-v4-flash
2026-08-01 09:45 UTC pith:DEAOGT4N
load-bearing objection A genuinely new construction—one fixed Hamiltonian plus two Pauli kicks—with a clean proof for GXE, but the deterministic-local-chain headline rests on an unproved delocalization ansatz. the 4 major comments →
Unitary k-designs without Hamiltonian quenches
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The central claim is that U_2PK(t1,t2,t3)=e^{-iHt3}P e^{-iHt2}P e^{-iHt1} is an approximate unitary k-design for k<d: its kth frame potential equals k![1+O(1/d)]. The proof shows the only structural object that matters is the doubly stochastic overlap matrix w_ab=|<E_a|P|E_b>|². One kick gives F^(1)=Tr(w²)→2 (GUE) or 3 (GOE); a second kick squares the kernel, leaving Tr(w⁴)=1+O(1/d), so the Haar value k! is simply the number of surviving index pairings. The single fixed Hamiltonian suffices even when it is a deterministic local spin chain, because Pauli conjugation preserves the norm while rotating the Hamiltonian to a nearly orthogonal effective partner, PH P, when the kick anticommutes wit
What carries the argument
The doubly stochastic matrix w_ab = |⟨E_a|P|E_b⟩|²—the Pauli kick in the energy eigenbasis—carries the entire argument. Its eigenvalues and the trace Tr(w⁴) control the frame potential, with the second kick promoting w²→w⁴ and thereby removing the O(1) excess that the one-kick protocol leaves. Locally, the same conjugation acts as a norm-preserving rotation with overlap ratio c=Tr(HPHP)/Tr(H²)=1−2f, where f is the fraction of Hamiltonian Frobenius weight flipped by the kick; |c|≪1 is the necessary condition for a local chain to form the design.
Load-bearing premise
The proof assumes the Pauli matrix elements in the energy eigenbasis are fully delocalized with |P_ab|²=1/d and Gaussian Wick-type statistics; if delocalization fails (near integrability or for low-weight kicks in a spin chain), the k! result breaks down.
What would settle it
Compute Tr(w⁴) (or the 2PK frame potential) for a strongly disordered or near-integrable spin chain with a Pauli kick of weight ω≈L/2: if Tr(w⁴) stays bounded away from 1 by an O(1) amount as d grows, then F_2PK^(k) will not approach k! and the design claim is refuted for that regime.
If this is right
- Approximate unitary k-designs can be realized with a single fixed chaotic Hamiltonian and a fixed Pauli kick, eliminating Hamiltonian quenches and random-Hamiltonian averaging.
- The frame potential bound F^(k,β)=k![Z(2β)/d]^k connects design formation to the equilibrium partition function, giving a finite-temperature design criterion.
- In deterministic local spin chains, high-weight Pauli kicks (weight ≳ L/2) generate designs with |c|≪1, whereas three-step quench protocols with weakly disordered Hamiltonians fail because independently drawn local Hamiltonians remain nearly parallel.
- Numerical convergence follows 1/d scaling (γ≈1 for k=2,3), so system sizes of d≈256 already show agreement with the Haar value within statistical error.
Where Pith is reading between the lines
- Because the only spectral input is non-resonance, the mechanism should survive for any fixed non-identity involutive kick, not necessarily a Pauli string, provided its energy-basis matrix elements delocalize; this is a testable claim.
- The overlap ratio c and the spectral gap 1−µ_2 of w are natural diagnostics: near integrability or localization, c→±1 and Tr(w⁴) deviates from 1, so frame-potential deviations should track these single-diagonalization quantities.
- The finite-temperature result suggests that measuring F^(k,β) of a single driven chain effectively measures the thermal purity Z(2β)/d, which could serve as an indirect thermometer or as a probe of thermalization in quantum simulators.
- The two-precursor holographic picture would imply a direct link between design order k and multi-shockwave geometry; a quantitative prediction for OTOC or entanglement growth at k=2 would sharpen this.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper introduces a two-Pauli-kick (2PK) temporal ensemble: a single fixed chaotic Hamiltonian H with two insertions of a fixed Pauli operator P, sampling three evolution times uniformly. It claims that the k-th frame potential approaches the Haar value k! up to O(1/d), so the ensemble forms an approximate unitary k-design for k<d, without Hamiltonian quenches or Hamiltonian ensembles. The authors derive an exact k=1 formula F_2PK^(1)=Tr(w^4) (SM S2), a controlled 1/d expansion for k≥2 under a delocalization ansatz (SM S3), verify the behavior numerically for GXE, Majorana/Spin SYK, and deterministic mixed-field Ising chains, and prove a finite-temperature lower bound in terms of the partition function (SM S7). The central claim is that the protocol works even for spatially local deterministic Hamiltonians, which is advertised as the first such demonstration.
Significance. If the central claim holds, the protocol is a significant step: it removes the need for multiple Hamiltonian realizations and extends unitary-design generation to deterministic local spin chains. The exact k=1 result, the transparent numerical verification, and the finite-temperature bound are solid components. However, the validity for non-GXE models, in particular the headline local-chain claim, rests on assumptions that are not proven: the delocalization ansatz A2 and an uncontrolled random-phase estimate. The significance is therefore conditional on these assumptions being either proven or clearly presented as conjectures with strong numerical support.
major comments (4)
- [SM S3, Assumption A2] The result for SYK and MFIM, Eq. (S37), F_2PK^(k)=k![Tr(w^4)]^k[1+O(1/d)], uses Assumption A2 — Gaussian delocalization of the matrix elements P_ab with Wick contractions — which is explicitly called an 'eigenvector-thermalization ansatz' and left unproved. This is load-bearing: if A2 fails, Tr(w^4) is not 1+O(1/d) and the design does not form (SM Table S1, Case 4). The main text (Eq. (4), Fig. 3) presents the local-chain result without this caveat. Please either prove A2 for a physically defined class of systems or state the result as conditional on a numerically supported ansatz.
- [SM S3 C, Eq. (S36)] The suppression of the σ≠τ permutation terms relies on an 'uncontrolled random-phase estimate' — the authors' own description — and is essential for the k! counting. For GXE a rigorous Weingarten argument is available, but for SYK and MFIM this constitutes a second assumption beyond A2. Please provide a rigorous bound or a direct numerical test of the claimed d^{-ν} scaling for the off-diagonal contributions.
- [SM S7, Eq. (S70)] The finite-temperature derivation assumes that an approximate k-design in the β=0 frame-potential sense yields the Haar average of |Tr(ρβG)|^{2k} with relative error O(1/d) for every β. This is not generally valid: for low-rank ρβ the error in the moment operator can dominate the leading Haar term, so the relative O(1/d) statement requires justification. Please derive Eq. (12) directly by time averaging under A1/A2, as done for the β=0 case, or provide a uniform-in-β error bound.
- [Main text, Conclusion] The statement that 2PK works 'even when spatially local' is not established for deterministic local chains because the proof depends on A2 and the random-phase estimate, and the numerical support is L=10 with a post-selected full-weight Pauli string (|c|≲0.2). SM S6 D itself states that |c|≪1 is necessary but not sufficient (Table S1, Case 4). The abstract and conclusion should be tempered or the claim should be supported with additional evidence, e.g., larger system sizes, multiple deterministic realizations, or a direct test of A2.
minor comments (4)
- [SM S7] In the sentence 'one has ⟨G_aa⟩=0 and, exactly, ⟨G_aa G_bb⟩=δ_ab/d', the second expectation should be ⟨G_aa G*_bb⟩=δ_ab/d; the variance formula below requires the conjugate.
- [Fig. 2 caption] The caption lists three items ('analytical prediction in (6) with Λ=3 (GOE)', 'Λ=2 (GUE)', and 'the Haar value k!') but only two dashed lines are visible in the figure. Please clarify the line styles for each.
- [SM S6 D] The term 'uniform string' is used without definition; please define it explicitly (e.g., a Pauli string whose non-identity entries are all the same letter).
- [Main text, after Eq. (6)] The closed-form expression for the 1PK frame potential is derived in SM S3 E; please add a pointer to that section when Eq. (6) is first used.
Circularity Check
No significant circularity: the k! design value is obtained by permutation counting, not by fitting; A2 is an acknowledged assumption rather than an enforced target.
full rationale
The derivation of Eq. (4) in SM S3 is self-contained: F_2PK^(k) = k! [Tr(w^4)]^k [1+O(1/d)] with k! counted from the diagonal (σ,σ) permutations in the time-averaged sum; the O(1/d) off-diagonal suppression is a random-phase estimate, not a fitted value. The Haar value is not used as input; it emerges from counting. Tr(w^4)=1+O(1/d) is exact for GXE via Haar eigenvectors and is explicitly labelled Assumption A2 ('eigenvector-thermalization ansatz') for SYK/MFIM, supported by numerics rather than imposed. The finite-temperature result (12) uses the previously established design property and the generic Haar calculation; the lower bound (13) is proven by an operator-positivity argument independent of 2PK. The |c|≪1 condition for local spin chains is presented as necessary but not sufficient, with failing Case 4 in Table S1 acknowledged. The only self-citation [25] supports the side remark that Spin SYK2 has rapid operator growth and is not load-bearing for the design claim. Thus no prediction reduces by construction to its inputs; the main limitations are unproved assumptions, not circularity.
Axiom & Free-Parameter Ledger
free parameters (2)
- Pauli kick selection threshold |c| ≲ 0.2 =
0.2
- Pauli weight requirement ω ≳ L/2 =
L/2 (L=10 cases use a full-weight string)
axioms (5)
- domain assumption A1: Non-resonance at order k: equal sums of k energies imply equal index multisets.
- domain assumption A2: Delocalization of the Pauli operator in the energy basis: |P_ab|²=1/d, with Wick-contraction moments and kurtosis Λ=2 (GUE) or 3 (GOE).
- ad hoc to paper For deterministic local spin chains, operator orthogonality |c|≪1 is sufficient for design formation.
- domain assumption The frame potential approaching k! is used as the criterion for an approximate unitary k-design.
- domain assumption Finite-temperature bound assumes the 2PK ensemble forms an approximate unitary k-design before evaluating the Haar average.
read the original abstract
Unitary designs provide a resource-efficient framework for emulating Haar randomness up to a desired order. Quench-based protocols have recently been shown to generate such designs, but achieving this typically requires multiple Hamiltonian realizations, even when using temporal ensembles. Here, we show that no Hamiltonian quenches are required: a single chaotic Hamiltonian is sufficient to generate approximate unitary $k$-designs, even when that Hamiltonian is spatially local. We introduce a two-Pauli-kick (2PK) protocol, in which unitary evolution under a fixed Hamiltonian is interspersed with two Pauli operator insertions (kicks). By evaluating the frame potential, we demonstrate that the resulting ensemble approaches the Haar value. We verify this protocol for single realizations of Gaussian random matrices, the Majorana and Spin Sachdev-Ye-Kitaev models, and deterministic local quantum spin chains. Remarkably, in these deterministic spin systems, the 2PK protocol generates approximate unitary designs in regimes where conventional quench-based protocols are either inapplicable or fail to converge. Furthermore, our protocol provides a finite-temperature extension of the frame potential and establishes an analytic bound in terms of the equilibrium partition function. We discuss a holographic perspective on this mechanism.
Figures
Reference graph
Works this paper leans on
-
[1]
Introduction to Haar Measure Tools in Quantum Information: A Beginner’s Tutorial,
Antonio Anna Mele, “Introduction to Haar Measure Tools in Quantum Information: A Beginner’s Tutorial,” Quantum8, 1340 (2024)
2024
-
[2]
Evenly dis- tributed unitaries: On the structure of unitary designs,
D. Gross, K. Audenaert, and J. Eisert, “Evenly dis- tributed unitaries: On the structure of unitary designs,” J. Math. Phys.48, 052104 (2007)
2007
-
[3]
Chaos and com- plexity by design,
Daniel A. Roberts and Beni Yoshida, “Chaos and com- plexity by design,” JHEP04, 121 (2017)
2017
-
[4]
Chaos, complexity, and random matri- ces,
Jordan Cotler, Nicholas Hunter-Jones, Junyu Liu, and Beni Yoshida, “Chaos, complexity, and random matri- ces,” JHEP11, 048 (2017)
2017
-
[5]
Pseudo-Random Uni- tary Operators for Quantum Information Processing,
Joseph Emerson, Yaakov S. Weinstein, Marcos Saraceno, Seth Lloyd, and David G. Cory, “Pseudo-Random Uni- tary Operators for Quantum Information Processing,” Science302, 2098–2100 (2003). 6
2098
-
[6]
more random
The gray and black dashed lines denote the analytical pre- diction in (6) with Λ = 3 (GOE), Λ = 2 (GUE), and the Haar valuek!, respectively. The long-time limit is obtained by takingT= 10 6. The system size isd= 2 8, and the results are averaged over 104 independent temporal realizations. write the frame potentials as F (k) 1PK =E {tj ,t′ j } Tr e−iD∆t1 P...
2026
-
[7]
Efficient Quantum Pseudorandom- ness,
Fernando G. S. L. Brand˜ ao, Aram W. Harrow, and Micha l Horodecki, “Efficient Quantum Pseudorandom- ness,” Phys. Rev. Lett.116, 170502 (2016)
2016
-
[8]
Models of Quantum Complexity Growth,
Fernando G. S. L. Brand˜ ao, Wissam Chemissany, Nicholas Hunter-Jones, Richard Kueng, and John Preskill, “Models of Quantum Complexity Growth,” PRX Quantum2, 030316 (2021)
2021
-
[9]
Random unitaries in extremely low depth,
Thomas Schuster, Jonas Haferkamp, and Hsin-Yuan Huang, “Random unitaries in extremely low depth,” Sci- ence389, adv8590 (2025)
2025
-
[10]
Unitary designs from statisti- cal mechanics in random quantum circuits,
Nicholas Hunter-Jones, “Unitary designs from statisti- cal mechanics in random quantum circuits,” (2019), arXiv:1905.12053 [quant-ph]
Pith/arXiv arXiv 2019
-
[11]
Emergent Quantum State Designs from Individual Many-Body Wave Functions,
Jordan S. Cotler, Daniel K. Mark, Hsin-Yuan Huang, Felipe Hernandez, Joonhee Choi, Adam L. Shaw, Manuel Endres, and Soonwon Choi, “Emergent Quantum State Designs from Individual Many-Body Wave Functions,” PRX Quantum4, 010311 (2023)
2023
-
[12]
Exact emergent quan- tum state designs from quantum chaotic dynamics,
Wen Wei Ho and Soonwon Choi, “Exact emergent quan- tum state designs from quantum chaotic dynamics,” Phys. Rev. Lett.128, 060601 (2022)
2022
-
[13]
Emergent quantum state designs and biunitarity in dual-unitary circuit dynamics,
Pieter W. Claeys and Austen Lamacraft, “Emergent quantum state designs and biunitarity in dual-unitary circuit dynamics,” Quantum6, 738 (2022)
2022
-
[14]
Designs via Free Probability,
Michele Fava, Jorge Kurchan, and Silvia Pappalardi, “Designs via Free Probability,” Phys. Rev. X15, 011031 (2025)
2025
-
[15]
Computational Complexity of Uni- tary and State Design Properties,
Yoshifumi Nakata, Yuki Takeuchi, Martin Kliesch, and Andrew Darmawan, “Computational Complexity of Uni- tary and State Design Properties,” PRX Quantum6, 030345 (2025)
2025
-
[16]
Free Independence and Unitary Design from Random Matrix Product Uni- taries,
Neil Dowling, Jacopo De Nardis, Markus Heinrich, Xhek Turkeshi, and Silvia Pappalardi, “Free Independence and Unitary Design from Random Matrix Product Uni- taries,” (2025), arXiv:2508.00051 [quant-ph]
arXiv 2025
-
[17]
Random unitaries from Hamiltonian dynamics,
Laura Cui, Thomas Schuster, Liang Mao, Hsin-Yuan Huang, and Fernando Brandao, “Random unitaries from Hamiltonian dynamics,” (2025), arXiv:2510.08434 [quant-ph]
arXiv 2025
-
[18]
Realizing Unitary k-Designs with a Single Quench,
Yi-Neng Zhou, Robin L¨ owenberg, and Julian Sonner, “Realizing Unitary k-Designs with a Single Quench,” Phys. Rev. Lett.136, 220403 (2026)
2026
-
[19]
Three Hamiltonians are Sufficient for Unitaryk-Design in Temporal Ensemble,
Yi-Neng Zhou, Tian-Gang Zhou, and Julian Sonner, “Three Hamiltonians are Sufficient for Unitaryk-Design in Temporal Ensemble,” (2026), arXiv:2604.04205 [quant-ph]
Pith/arXiv arXiv 2026
-
[20]
Quantum work statistics, Loschmidt echo and information scrambling,
A. Chenu, I. L. Egusquiza, J. Molina-Vilaplana, and A. del Campo, “Quantum work statistics, Loschmidt echo and information scrambling,” Sci. Rep.8, 12634 (2018)
2018
-
[21]
Work Statistics, Loschmidt Echo and In- formation Scrambling in Chaotic Quantum Systems,
Aur´ elia Chenu, Javier Molina-Vilaplana, and Adolfo Del Campo, “Work Statistics, Loschmidt Echo and In- formation Scrambling in Chaotic Quantum Systems,” Quantum3, 127 (2019)
2019
-
[22]
Unitary Designs from Two Chaotic Hamiltonians and a Random Pauli Operation,
Ning Sun and Pengfei Zhang, “Unitary Designs from Two Chaotic Hamiltonians and a Random Pauli Operation,” (2026), arXiv:2604.10122 [quant-ph]
Pith/arXiv arXiv 2026
-
[23]
Optimizing quantum process tomography with unitary 2-designs,
A J Scott, “Optimizing quantum process tomography with unitary 2-designs,” Journal of Physics A: Mathe- matical and Theoretical41, 055308 (2008)
2008
-
[24]
Gapless spin-fluid ground state in a random quantum heisenberg magnet,
Subir Sachdev and Jinwu Ye, “Gapless spin-fluid ground state in a random quantum heisenberg magnet,” Phys. Rev. Lett.70, 3339–3342 (1993)
1993
-
[25]
A simple model of quantum holography (part 1) and (part 2),
A. Kitaev, “A simple model of quantum holography (part 1) and (part 2),”https://online.kitp.ucsb.edu/ online/joint98/kitaev/,https://online.kitp.ucsb. edu/online/entangled15/kitaev2/(2015), talk given at KITP
2015
-
[26]
Complex- ity of quadratic quantum chaos,
Pallab Basu, Suman Das, and Pratik Nandy, “Complex- ity of quadratic quantum chaos,” JHEP04, 081 (2026)
2026
-
[27]
Ultra-stable charg- ing of fast-scrambling SYK quantum batteries,
Dario Rosa, Davide Rossini, Gian Marcello Andolina, Marco Polini, and Matteo Carrega, “Ultra-stable charg- ing of fast-scrambling SYK quantum batteries,” JHEP 11, 067 (2020)
2020
-
[28]
Sachdev-Ye-Kitaev model and thermalization on the boundary of many-body localized fermionic symmetry- protected topological states,
Yi-Zhuang You, Andreas W. W. Ludwig, and Cenke Xu, “Sachdev-Ye-Kitaev model and thermalization on the boundary of many-body localized fermionic symmetry- protected topological states,” Phys. Rev. B95, 115150 (2017)
2017
-
[29]
A model of randomly- coupled Pauli spins,
Masanori Hanada, Antal Jevicki, Xianlong Liu, Enrico Rinaldi, and Masaki Tezuka, “A model of randomly- coupled Pauli spins,” JHEP05, 280 (2024)
2024
-
[30]
Localization of interacting fermions at high temperature,
Vadim Oganesyan and David A. Huse, “Localization of interacting fermions at high temperature,” Phys. Rev. B 75, 155111 (2007)
2007
-
[31]
Distribution of the ratio of consecutive level spacings in random matrix ensembles,
Y. Y. Atas, E. Bogomolny, O. Giraud, and G. Roux, “Distribution of the ratio of consecutive level spacings in random matrix ensembles,” Phys. Rev. Lett.110, 084101 (2013)
2013
-
[32]
Solvable Ran- dom Unitary Dynamics in a Disordered Tomonaga- Luttinger Liquid,
Tian-Gang Zhou and Thierry Giamarchi, “Solvable Ran- dom Unitary Dynamics in a Disordered Tomonaga- Luttinger Liquid,” (2026), arXiv:2604.25995 [quant-ph]
Pith/arXiv arXiv 2026
-
[33]
Linear growth of circuit complexity from Brownian dy- namics,
Shao-Kai Jian, Gregory Bentsen, and Brian Swingle, “Linear growth of circuit complexity from Brownian dy- namics,” JHEP08, 190 (2023)
2023
-
[34]
A bound on chaos,
Juan Maldacena, Stephen H. Shenker, and Douglas Stanford, “A bound on chaos,” JHEP08, 106 (2016)
2016
-
[35]
Complexity and shock wave geometries,
Douglas Stanford and Leonard Susskind, “Complexity and shock wave geometries,” Phys. Rev. D90, 126007 (2014)
2014
-
[36]
Chaotic- Integrable Transition in the Sachdev-Ye-Kitaev Model,
Antonio M. Garc ´ ıa-Garc ´ ıa, Bruno Loureiro, Aurelio Romero-Berm´ udez, and Masaki Tezuka, “Chaotic- Integrable Transition in the Sachdev-Ye-Kitaev Model,” Phys. Rev. Lett.120, 241603 (2018)
2018
-
[37]
“Repulsion of Energy Levels
Norbert Rosenzweig and Charles E. Porter, ““Repulsion of Energy Levels” in Complex Atomic Spectra,” Phys. Rev.120, 1698–1714 (1960)
1960
-
[38]
A random matrix model with localization and ergodic transitions,
V. E. Kravtsov, I. M. Khaymovich, E. Cuevas, and M. Amini, “A random matrix model with localization and ergodic transitions,” New J. Phys.17, 122002 (2015)
2015
-
[39]
The Rosen- zweig–Porter model revisited for the three Wigner–Dyson symmetry classes,
Tilen ˇCadeˇ z, Dillip Kumar Nandy, Dario Rosa, Alexei Andreanov, and Barbara Dietz, “The Rosen- zweig–Porter model revisited for the three Wigner–Dyson symmetry classes,” New J. Phys.26, 083018 (2024)
2024
-
[40]
Free probability ap- proach to spectral and operator statistics in Rosenzweig- Porter random matrix ensembles,
Viktor Jahnke, Pratik Nandy, Kuntal Pal, Hugo A. Ca- margo, and Keun-Young Kim, “Free probability ap- proach to spectral and operator statistics in Rosenzweig- Porter random matrix ensembles,” JHEP12, 002 (2025)
2025
-
[41]
Multiple shocks,
Stephen H. Shenker and Douglas Stanford, “Multiple shocks,” JHEP12, 046 (2014)
2014
-
[42]
Random circuits in the black hole interior,
Javier M. Magan, Martin Sasieta, and Brian Swingle, “Random circuits in the black hole interior,” SciPost Phys.19, 007 (2025)
2025
-
[43]
ER for typical EPR,
Javier M. Mag´ an, Martin Sasieta, and Brian Swingle, “ER for typical EPR,” Phys. Rev. Lett.135, 161601 (2025)
2025
-
[44]
Quantum microstate counting from Brownian motion: 7 from many-body systems to black holes,
Enzo Bavaro, Javier M. Magan, and Leandro Martinek, “Quantum microstate counting from Brownian motion: 7 from many-body systems to black holes,” (2025), arXiv:2512.15854 [hep-th]
arXiv 2025
-
[45]
Statek-designs from Hamiltonian evolution,
Shengxian Hou, Zong-Yue Hou, and Zhi-Cheng Yang, “Statek-designs from Hamiltonian evolution,” (2026), arXiv:2607.18537 [quant-ph]
Pith/arXiv arXiv 2026
-
[46]
Quantum signatures of chaos from free probability,
Hugo A. Camargo, Yichao Fu, Viktor Jahnke, Keun- Young Kim, and Kuntal Pal, “Quantum signatures of chaos from free probability,” JHEP10, 138 (2025)
2025
-
[47]
A Universal Oper- ator Growth Hypothesis,
Daniel E. Parker, Xiangyu Cao, Alexander Avdoshkin, Thomas Scaffidi, and Ehud Altman, “A Universal Oper- ator Growth Hypothesis,” Phys. Rev. X9, 041017 (2019). 8 Supplemental Material: Unitaryk-designs without Hamiltonian quenches Pratik Nandy1,2 1Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB) and The International Solvay Institutes, Pleinlaan...
2019
-
[48]
eiEmt2 e−iEnt′ 2 .(S15) The two middle timest 2 (fromU) andt ′ 2 (fromV) enterseparatelyrather than as a difference; this is the structural signature of the two kicks and the origin of the two intermediate labelsm, n. The first-order frame potential isF (1) 2PK = |z|2, the overline denoting the average over the six times{t i, t′ i}for i= 1,2,3, each unifo...
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.