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RG flows in de Sitter: C-functions and sum rules 德西特中的 RG 流C 函数与和规则
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-12 DOI: 10.21468/scipostphys.17.3.079
Manuel Loparco
We study the renormalization group flow of unitary Quantum Field Theories on two-dimensional de Sitter (dS) spacetime. We prove the existence of two functions of the radius of dS that interpolate between the central charges of the UV and IR fixed points of the flow when tuning the radius $R$ while keeping the mass scales fixed. The first is constructed from certain components of the two-point function of the stress tensor evaluated at antipodal separation. The second is the spectral weight of the stress tensor in the $Delta=2$ discrete series. This last fact implies that the stress tensor of any unitary QFT in dS$_2$ must interpolate between the vacuum and states in the $Delta=2$ discrete series irrep. We verify that the c-functions are monotonic for intermediate radii in the free massive boson and free massive fermion theories, but we lack a general proof of said monotonicity. We derive a variety of sum rules that relate the central charges and the c-functions to integrals of the two-point function of the trace of the stress tensor and to integrals of its spectral densities. The positivity of these formulas implies $c^{UV}≥ c^{IR}$. In the infinite radius limit the sum rules reduce to the well known formulas in flat space. Throughout the paper, we prove some general properties of the spectral decomposition of the stress tensor in dS$_{d+1}$.
我们研究二维德西特(dS)时空上单元量子场论的重正化群流。我们证明了 dS 半径的两个函数的存在,当调整半径 $R$ 并保持质量标度固定时,这两个函数可以在流的紫外固定点和红外固定点的中心电荷之间插值。第一种方法是根据在对偶分离处评估的应力张量两点函数的某些分量构建的。第二个是应力张量在 $Delta=2$ 离散序列中的频谱权重。最后一个事实意味着,dS$_2$ 中任何单元 QFT 的应力张量都必须在真空与 $Delta=2$ 离散序列 irrep 中的状态之间插值。我们验证了在自由大质量玻色子和自由大质量费米子理论中,c 函数对于中间半径是单调的,但我们缺乏对上述单调性的一般性证明。我们推导出各种和规则,它们将中心电荷和 c 函数与应力张量迹的两点函数积分及其谱密度积分联系起来。这些公式的正向性意味着 $c^{UV}≥c^{IR}$。在无限半径极限中,和规则还原为平面空间中众所周知的公式。在整篇论文中,我们证明了 dS$_{d+1}$ 中应力张量谱分解的一些一般性质。
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引用次数: 0
Lorentzian contours for tree-level string amplitudes 树级弦振幅的洛伦兹等值线
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-11 DOI: 10.21468/scipostphys.17.3.078
Lorenz Eberhardt, Sebastian Mizera
We engineer compact contours on the moduli spaces of genus-zero Riemann surfaces that achieve analytic continuation from Euclidean to Lorentzian worldsheets. These generalized Pochhammer contours are based on the combinatorics of associahedra and make the analytic properties of tree-level amplitudes entirely manifest for any number and type of external strings. We use them in practice to perform first numerical computations of open and closed string amplitudes directly in the physical kinematics for $n=4,5,6,7,8,9$. We provide a code that allows anyone to do such computations.
我们在零属黎曼曲面的模空间上设计了紧凑的等值线,实现了从欧几里得世界曲面到洛伦兹世界曲面的解析延续。这些广义的波克夏默等值线基于联方体的组合学,使得树级振幅的分析特性在任何数量和类型的外部弦上都能完全体现出来。我们在实践中使用它们,首次直接在物理运动学中对$n=4,5,6,7,8,9$的开放弦和封闭弦振幅进行数值计算。我们提供的代码允许任何人进行此类计算。
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引用次数: 0
On a $mathbb{Z}_3$-valued discrete topological term in 10d heterotic string theories 关于 10d 异质弦理论中的 $mathbb{Z}_3$ 值离散拓扑项
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-11 DOI: 10.21468/scipostphys.17.3.077
Yuji Tachikawa, Hao Zhang
We show that the low-energy effective actions of two ten-dimensional supersymmetric heterotic strings are different by a $mathbb{Z}_3$-valued discrete topological term even after we turn off the $E_8×E_8$ and $Spin(32)/mathbb{Z}_2$ gauge fields. This will be demonstrated by considering the inflow of normal bundle anomaly to the respective NS5-branes from the bulk. This result will be used to show further that the $Spin(16)×Spin(16)$ non-tachyonic non-supersymmetric heterotic string has the same non-zero $mathbb{Z}_3$-valued discrete topological term. We will also explain the relation of our findings to the theory of topological modular forms. The paper is written as a string theory paper, except for an appendix translating the content in mathematical terms. We will explain there that our finding identifies a representative of the $mathbb{Z}/3$-torsion element of $pi_{-32}mathrm{TMF}$ as a particular self-dual vertex operator superalgebra of $c=16$ and how we utilize string duality to arrive at this statement.
我们证明,即使关闭了$E_8×E_8$和$Spin(32)/mathbb{Z}_2$规场,两个十维超对称异质弦的低能有效作用也会因为一个$mathbb{Z}_3$值的离散拓扑项而不同。这将通过考虑法向束反常性从体流入各自的 NS5-branes来证明。我们将利用这一结果进一步证明,$Spin(16)×Spin(16)$ 非塔基非超对称异质弦具有相同的非零$mathbb{Z}_3$值离散拓扑项。我们还将解释我们的发现与拓扑模块形式理论的关系。除了用数学术语翻译内容的附录之外,这篇论文是以弦理论论文的形式撰写的。我们将在附录中解释,我们的发现将 $pi_{-32}mathrm{TMF}$ 的 $mathbb{Z}/3$ 扭转元的一个代表确定为 $c=16$ 的一个特殊自偶顶点算子超代数,以及我们是如何利用弦对偶性得出这一结论的。
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引用次数: 0
Unraveling complexity: Singular value decomposition in complex experimental data analysis 揭示复杂性:复杂实验数据分析中的奇异值分解
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-11 DOI: 10.21468/scipostphyscore.7.3.061
Judith F. Stein, Aviad Frydman, Richard Berkovits
Analyzing complex experimental data with multiple parameters is challenging. We propose using Singular Value Decomposition (SVD) as an effective solution. This method, demonstrated through real experimental data analysis, surpasses conventional approaches in understanding complex physics data. Singular values and vectors distinguish and highlight various physical mechanisms and scales, revealing previously challenging elements. SVD emerges as a powerful tool for navigating complex experimental landscapes, showing promise for diverse experimental measurements.
分析具有多个参数的复杂实验数据具有挑战性。我们建议使用奇异值分解(SVD)作为有效的解决方案。通过实际实验数据分析证明,这种方法在理解复杂物理数据方面超越了传统方法。奇异值和矢量能区分并突出各种物理机制和尺度,揭示以前难以理解的元素。SVD 是浏览复杂实验景观的有力工具,为各种实验测量带来了希望。
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引用次数: 0
Suppression of the superfluid Kelvin-Helmholtz instability due to massive vortex cores, friction and confinement 大质量涡核、摩擦和约束对超流体开尔文-赫尔姆霍兹不稳定性的抑制
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-10 DOI: 10.21468/scipostphys.17.3.076
Matteo Caldara, Andrea Richaud, Massimo Capone, Pietro Massignan
We characterize the dynamical instability responsible for the breakdown of regular rows and necklaces of quantized vortices that appear at the interface between two superfluids in relative motion. Making use of a generalized point-vortex model, we identify several mechanisms leading to the suppression of this instability. They include a non-zero mass of the vortex cores, dissipative processes resulting from the interaction between the vortices and the excitations of the superfluid, and the proximity of the vortex array to the sample boundaries. We show that massive vortex cores not only have a mitigating effect on the dynamical instability, but also change the associated scaling law and affect the direction along which it develops. The predictions of our massive and dissipative point-vortex model are eventually compared against recent experimental measurements of the maximum instability growth rate relevant to vortex necklaces in a cold-atom platform.
我们描述了在两个相对运动的超流体之间的界面上出现的量子化涡旋的规则行和项链破裂的动态不稳定性的特征。利用广义点涡旋模型,我们确定了导致抑制这种不稳定性的几种机制。这些机制包括漩涡核心的非零质量、漩涡与超流体激发之间相互作用产生的耗散过程,以及漩涡阵列与样品边界的接近程度。我们的研究表明,大质量涡核不仅对动力学不稳定性有缓解作用,还能改变相关的缩放规律,并影响其发展方向。我们最终将大质量耗散点涡旋模型的预测结果与冷原子平台中涡旋项链相关的最大不稳定性增长率的最新实验测量结果进行了比较。
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引用次数: 0
An introduction to infinite projected entangled-pair state methods for variational ground state simulations using automatic differentiation 利用自动微分进行变异基态模拟的无限投影纠缠对态方法简介
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-10 DOI: 10.21468/scipostphyslectnotes.86
Jan Naumann, Erik Lennart Weerda, Matteo Rizzi, Jens Eisert, Philipp Schmoll
Tensor networks capture large classes of ground states of phases of quantum matter faithfully and efficiently. Their manipulation and contraction has remained a challenge over the years, however. For most of the history, ground state simulations of two-dimensional quantum lattice systems using (infinite) projected entangled pair states have relied on what is called a time-evolving block decimation. In recent years, multiple proposals for the variational optimization of the quantum state have been put forward, overcoming accuracy and convergence problems of previously known methods. The incorporation of automatic differentiation in tensor networks algorithms has ultimately enabled a new, flexible way for variational simulation of ground states and excited states. In this work we review the state-of-the-art of the variational iPEPS framework, providing a detailed introduction to automatic differentiation, a description of a general foundation into which various two-dimensional lattices can be conveniently incorporated, and demonstrative benchmarking results.
张量网络能忠实而高效地捕捉量子物质相的大量基态。然而,多年来,张量网络的操作和收缩仍然是一项挑战。在历史上的大部分时间里,使用(无限)投影纠缠对态的二维量子晶格系统的基态模拟都依赖于所谓的时间演进块抽取。近年来,人们提出了量子态变分优化的多种方案,克服了之前已知方法的精度和收敛性问题。将自动微分纳入张量网络算法,最终为基态和激发态的变分模拟提供了一种新的、灵活的方法。在这项工作中,我们回顾了变分 iPEPS 框架的最新进展,详细介绍了自动微分,描述了可以方便地将各种二维晶格纳入其中的一般基础,以及示范性基准结果。
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引用次数: 0
Markovian to non-Markovian phase transition in the operator dynamics of a mobile impurity 移动杂质算子动力学中的马尔可夫相变到非马尔可夫相变
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-09 DOI: 10.21468/scipostphyscore.7.3.060
Dominic Gribben, Jamir Marino, Shane P. Kelly
We study a random unitary circuit model of an impurity moving through a chaotic medium. The exchange of information between the medium and impurity is controlled by varying the velocity of the impurity, $v_d$, relative to the speed of information propagation within the medium, $v_B$. Above supersonic velocities, $v_d> v_B$, information cannot flow back to the impurity after it has moved into the medium, and the resulting dynamics are Markovian. Below supersonic velocities, $v_d< v_B$, the dynamics of the impurity and medium are non-Markovian, and information is able to flow back onto the impurity. We show the two regimes are separated by a continuous phase transition with exponents directly related to the diffusive spreading of operators in the medium. This is demonstrated by monitoring an out-of-time-order correlator (OTOC) in a scenario where the impurity is substituted at an intermediate time. During the Markovian phase, information from the medium cannot transfer onto the replaced impurity, manifesting in no significant operator development. Conversely, in the non-Markovian phase, we observe that operators acquire support on the newly introduced impurity. We also characterize the dynamics using the coherent information and provide two decoders which can efficiently probe the transition between Markovian and non-Markovian information flow. Our work demonstrates that Markovian and non-Markovian dynamics can be separated by a phase transition, and we propose an efficient protocol for observing this transition.
我们研究的是杂质在混沌介质中运动的随机单元电路模型。介质和杂质之间的信息交换是通过改变杂质的速度 $v_d$ 和介质中的信息传播速度 $v_B$ 来控制的。在超音速($v_d> v_B$)以上,信息在进入介质后无法流回杂质,由此产生的动力学是马尔可夫式的。在超音速以下,即 $v_d<v_B$,杂质和介质的动力学是非马尔可夫式的,信息能够回流到杂质上。我们的研究表明,这两种状态被一个连续的相变分隔开来,相变指数与算子在介质中的扩散直接相关。我们通过在中间时间替换杂质的情况下监测时序外相关器(OTOC)来证明这一点。在马尔可夫阶段,介质中的信息无法转移到被替代的杂质上,表现为算子没有明显的发展。相反,在非马尔可夫阶段,我们观察到算子在新引入的杂质上获得了支持。我们还利用相干信息描述了动态特性,并提供了两种解码器,可以有效探测马尔可夫信息流和非马尔可夫信息流之间的过渡。我们的研究表明,马尔可夫动态和非马尔可夫动态可以通过相变分离,我们还提出了一种观测这种相变的高效协议。
{"title":"Markovian to non-Markovian phase transition in the operator dynamics of a mobile impurity","authors":"Dominic Gribben, Jamir Marino, Shane P. Kelly","doi":"10.21468/scipostphyscore.7.3.060","DOIUrl":"https://doi.org/10.21468/scipostphyscore.7.3.060","url":null,"abstract":"We study a random unitary circuit model of an impurity moving through a chaotic medium. The exchange of information between the medium and impurity is controlled by varying the velocity of the impurity, $v_d$, relative to the speed of information propagation within the medium, $v_B$. Above supersonic velocities, $v_d&gt; v_B$, information cannot flow back to the impurity after it has moved into the medium, and the resulting dynamics are Markovian. Below supersonic velocities, $v_d&lt; v_B$, the dynamics of the impurity and medium are non-Markovian, and information is able to flow back onto the impurity. We show the two regimes are separated by a continuous phase transition with exponents directly related to the diffusive spreading of operators in the medium. This is demonstrated by monitoring an out-of-time-order correlator (OTOC) in a scenario where the impurity is substituted at an intermediate time. During the Markovian phase, information from the medium cannot transfer onto the replaced impurity, manifesting in no significant operator development. Conversely, in the non-Markovian phase, we observe that operators acquire support on the newly introduced impurity. We also characterize the dynamics using the coherent information and provide two decoders which can efficiently probe the transition between Markovian and non-Markovian information flow. Our work demonstrates that Markovian and non-Markovian dynamics can be separated by a phase transition, and we propose an efficient protocol for observing this transition.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Adiabatic gauge potential and integrability breaking with free fermions 绝热规势与自由费米子的可整性突破
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-09 DOI: 10.21468/scipostphys.17.3.075
Balázs Pozsgay, Rustem Sharipov, Anastasiia Tiutiakina, István Vona
We revisit the problem of integrability breaking in free fermionic quantum spin chains. We investigate the so-called adiabatic gauge potential (AGP), which was recently proposed as an accurate probe of quantum chaos. We also study the so-called weak integrability breaking, which occurs if the dynamical effects of the perturbation do not appear at leading order in the perturbing parameter. A recent statement in the literature claimed that integrability breaking should generally lead to an exponential growth of the AGP norm with respect to the volume. However, afterwards it was found that weak integrability breaking is a counter-example, leading to a cross-over between polynomial and exponential growth. Here we show that in free fermionic systems the AGP norm always grows polynomially, if the perturbation is local with respect to the fermions, even if the perturbation strongly breaks integrability. As a by-product of our computations we also find, that in free fermionic spin chains there are operators which weakly break integrability, but which are not associated with known long range deformations.
我们重温了自由费米子量子自旋链中的可整性破缺问题。我们研究了所谓的绝热规势(AGP),它是最近提出的量子混沌的精确探测器。我们还研究了所谓的弱不整定性破缺,如果扰动的动态效应没有出现在扰动参数的前导阶,就会发生这种破缺。最近有文献称,可整性破缺一般会导致 AGP 准则相对于体积的指数增长。然而,后来人们发现,弱可整性破缺是一个反例,会导致多项式增长和指数增长之间的交叉。在这里,我们证明了在自由费米子系统中,如果相对于费米子的扰动是局部的,即使扰动强烈地打破了可整性,AGP 准则也总是多项式增长。作为计算的副产品,我们还发现,在自由费米子自旋链中,有一些算子弱地破坏了可整性,但它们与已知的长程变形无关。
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引用次数: 0
Flux-tunable hybridization in a double quantum dot interferometer 双量子点干涉仪中的通量可调杂化
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-06 DOI: 10.21468/scipostphys.17.3.074
Christian Prosko, Ivan Kulesh, Michael Chan, Lin Han, Di Xiao, Candice Thomas, Michael Manfra, Srijit Goswami, Filip K. Malinowski
Quantum interference of electron tunneling occurs in any system where multiple tunneling paths connect states. This unavoidably arises in two-dimensional semiconducting qubit arrays, and must be controlled as a prerequisite for the manipulation and readout of hybrid topological and parity qubits. Studying a loop formed by two quantum dots, we demonstrate a magnetic-flux-tunable hybridization between two electronic levels, an irreducibly simple system where quantum interference is expected to occur. Using radio-frequency reflectometry of the dots’ gate electrodes we extract an interdot coupling exhibiting oscillations with a periodicity of one flux quantum. In different tunneling regimes we benchmark the oscillations’ contrast, and find their amplitude varies with the charge state of the quantum dots. These results establish the feasibility and limitations of parity readout of qubits with tunnel couplings tuned by flux.
电子隧穿的量子干扰发生在任何有多条隧穿路径连接状态的系统中。在二维半导体量子比特阵列中,这种干扰不可避免地会出现,必须加以控制,这是操作和读出混合拓扑和奇偶校验量子比特的先决条件。通过研究由两个量子点形成的环路,我们展示了两个电子水平之间磁通量可调的杂化,这是一个不可还原的简单系统,预计会发生量子干涉。通过对量子点的栅极进行射频反射测量,我们提取出了一种点间耦合,其振荡周期为一个磁通量子。在不同的隧道状态下,我们对振荡的对比度进行了基准测试,发现振荡的幅度随量子点的电荷状态而变化。这些结果证明了用流量调整隧道耦合的量子比特进行奇偶性读出的可行性和局限性。
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引用次数: 0
Coulomb branch surgery: Holonomy saddles, S-folds and discrete symmetry gaugings 库仑分支手术:整体性鞍座、S 折叠和离散对称规
IF 5.5 2区 物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-09-05 DOI: 10.21468/scipostphys.17.3.073
Elias Furrer, Horia Magureanu
Symmetries of Seiberg–Witten (SW) geometries capture intricate physical aspects of the underlying 4d $mathcal{N} = 2$ field theories. For rank-one theories, these geometries are rational elliptic surfaces whose automorphism group is a semi-direct product between the Coulomb branch (CB) symmetries and the Mordell-Weil group. We study quotients of the SW geometry by subgroups of its automorphism group, which most naturally become gaugings of discrete 0- and 1-form symmetries. Yet, new interpretations of these surgeries become evident when considering 5d $mathcal{N}=1$ superconformal field theories. There, certain CB symmetries are related to symmetries of the corresponding $(p,q)$-brane web and, as a result, CB surgeries can give rise to (fractional) S-folds. Another novel interpretation of these quotients is the folding across dimensions: circle compactifications of the 5d $E_{2N_f + 1}$ Seiberg theories lead in the infrared to two copies of locally indistinguishable 4d SU(2) SQCD theories with $N_f$ fundamental flavours. This extends earlier results on holonomy saddles, while also reproducing detailed computations of 5d BPS spectra and predicting new 5d and 6d BPS quivers. Finally, we argue that the semi-direct product structure of the automorphism group of the SW geometry includes mixed 't Hooft anomalies between the 0- and 1-form symmetries, and we also present some new results on non-cyclic CB symmetries.
塞伯格-维滕(Seiberg-Witten,SW)几何对称性捕捉了底层 4d $mathcal{N} = 2$ 场理论错综复杂的物理方面。对于秩一理论,这些几何是有理椭圆曲面,其自形群是库仑支(CB)对称性与莫德尔-韦尔群之间的半直积。我们通过其自形群的子群研究 SW 几何的商,这些子群最自然地成为离散 0 形和 1 形对称的参量。然而,在考虑 5d $mathcal{N}=1$ 超共形场论时,这些手术的新解释就变得显而易见了。在那里,某些CB对称性与相应的$(p,q)$-brane web的对称性相关,因此,CB手术可以产生(分数)S折叠。这些商的另一个新解释是跨维折叠:5d $E_{2N_f + 1}$ 塞伯格理论的圆压缩在红外引出了两个具有 $N_f$ 基本味的局部无差别 4d SU(2) SQCD 理论。这扩展了早先关于整体鞍的结果,同时也重现了 5d BPS 谱的详细计算,并预测了新的 5d 和 6d BPS 夸父。最后,我们论证了 SW 几何的自变群的半直积结构包括 0 形和 1 形对称性之间的混合 't Hooft 异常,我们还提出了一些关于非循环 CB 对称性的新结果。
{"title":"Coulomb branch surgery: Holonomy saddles, S-folds and discrete symmetry gaugings","authors":"Elias Furrer, Horia Magureanu","doi":"10.21468/scipostphys.17.3.073","DOIUrl":"https://doi.org/10.21468/scipostphys.17.3.073","url":null,"abstract":"Symmetries of Seiberg–Witten (SW) geometries capture intricate physical aspects of the underlying 4d $mathcal{N} = 2$ field theories. For rank-one theories, these geometries are rational elliptic surfaces whose automorphism group is a semi-direct product between the Coulomb branch (CB) symmetries and the Mordell-Weil group. We study quotients of the SW geometry by subgroups of its automorphism group, which most naturally become gaugings of discrete 0- and 1-form symmetries. Yet, new interpretations of these surgeries become evident when considering 5d $mathcal{N}=1$ superconformal field theories. There, certain CB symmetries are related to symmetries of the corresponding $(p,q)$-brane web and, as a result, CB surgeries can give rise to (fractional) S-folds. Another novel interpretation of these quotients is the folding across dimensions: circle compactifications of the 5d $E_{2N_f + 1}$ Seiberg theories lead in the infrared to two copies of locally indistinguishable 4d SU(2) SQCD theories with $N_f$ fundamental flavours. This extends earlier results on holonomy saddles, while also reproducing detailed computations of 5d BPS spectra and predicting new 5d and 6d BPS quivers. Finally, we argue that the semi-direct product structure of the automorphism group of the SW geometry includes mixed 't Hooft anomalies between the 0- and 1-form symmetries, and we also present some new results on non-cyclic CB symmetries.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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