{"title":"Failures of the Feynman-Dyson diagrammatic perturbation expansion of propagators","authors":"So Hirata, Ireneusz Grabowski, Rodney J. Bartlett","doi":"arxiv-2312.03157","DOIUrl":"https://doi.org/arxiv-2312.03157","url":null,"abstract":"Using a general-order many-body Green's-function method for molecules, we\u0000illustrate numerically three pathological behaviors of the Feynman-Dyson\u0000diagrammatic perturbation expansion of one-particle many-body Green's functions\u0000as electron propagators. First, the perturbation expansion of the\u0000frequency-dependent self-energy is nonconvergent at the exact self-energy in\u0000wide domains of frequency. Second, the Dyson equation with an odd-order\u0000self-energy has a qualitatively wrong shape and, as a result, most of their\u0000satellite roots are complex and nonphysical. Third, the Dyson equation with an\u0000even-order self-energy has an exponentially increasing number of roots as the\u0000perturbation order is raised, which quickly exceeds the correct number of\u0000roots. Infinite partial summation of diagrams by vertex or edge modification\u0000exacerbates these problems. Not only does the nonconvergence render\u0000higher-order perturbation theories useless for satellite roots, but it also\u0000calls into question the validity of their combined use with the ans\"{a}tze\u0000requiring the knowledge of all poles and residues. Such ans\"{a}tze include the\u0000Galitskii-Migdal formula, self-consistent Green's-function methods,\u0000Luttinger-Ward functional, and some models of the algebraic diagrammatic\u0000construction.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138545964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giovanni Scala, Anindita Bera, Gniewomir Sarbicki, Dariusz Chruściński
{"title":"Optimality of generalized Choi maps in $M_3$","authors":"Giovanni Scala, Anindita Bera, Gniewomir Sarbicki, Dariusz Chruściński","doi":"arxiv-2312.02814","DOIUrl":"https://doi.org/arxiv-2312.02814","url":null,"abstract":"A family of linear positive maps in the algebra of $3 times 3$ complex\u0000matrices proposed recently in Bera et al. arXiv:2212.03807 is further analyzed.\u0000It provides a generalization of a seminal Choi nondecomposable extremal map in\u0000$M_3$. We investigate when generalized Choi maps are optimal, i.e. cannot be\u0000represented as a sum of positive and completely positive maps. This property is\u0000weaker than extremality, however, it turns out that it plays a key role in\u0000detecting quantum entanglement.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138525275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Calculation of Relativistic Single-Particle States","authors":"D. Wingard, B. Kónya, Z. Papp","doi":"arxiv-2312.02500","DOIUrl":"https://doi.org/arxiv-2312.02500","url":null,"abstract":"A computational method is proposed to calculate bound and resonant states by\u0000solving the Klein-Gordon and Dirac equations for real and complex energies,\u0000respectively. The method is an extension of a non-relativistic one, where the\u0000potential is represented in a Coulomb-Sturmian basis. This basis facilitates\u0000the exact analytic evaluation of the Coulomb Green's operator in terms of a\u0000continued fraction. In the extension to relativistic problems, we cast the\u0000Klein-Gordon and Dirac equations into an effective Schr\"odinger form. Then the\u0000solution method is basically an analytic continuation of non-relativistic\u0000quantities like the angular momentum, charge, energy and potential into the\u0000effective relativistic counterparts.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138525276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantum simulation for time-dependent Hamiltonians -- with applications to non-autonomous ordinary and partial differential equations","authors":"Yu Cao, Shi Jin, Nana Liu","doi":"arxiv-2312.02817","DOIUrl":"https://doi.org/arxiv-2312.02817","url":null,"abstract":"Non-autonomous dynamical systems appear in a very wide range of interesting\u0000applications, both in classical and quantum dynamics, where in the latter case\u0000it corresponds to having a time-dependent Hamiltonian. However, the quantum\u0000simulation of these systems often needs to appeal to rather complicated\u0000procedures involving the Dyson series, considerations of time-ordering,\u0000requirement of time steps to be discrete and/or requiring multiple measurements\u0000and postselection. These procedures are generally much more complicated than\u0000the quantum simulation of time-independent Hamiltonians. Here we propose an\u0000alternative formalism that turns any non-autonomous unitary dynamical system\u0000into an autonomous unitary system, i.e., quantum system with a time-independent\u0000Hamiltonian, in one higher dimension, while keeping time continuous. This makes\u0000the simulation with time-dependent Hamiltonians not much more difficult than\u0000that of time-independent Hamiltonians, and can also be framed in terms of an\u0000analogue quantum system evolving continuously in time. We show how our new\u0000quantum protocol for time-dependent Hamiltonians can be performed in a\u0000resource-efficient way and without measurements, and can be made possible on\u0000either continuous-variable, qubit or hybrid systems. Combined with a technique\u0000called Schrodingerisation, this dilation technique can be applied to the\u0000quantum simulation of any linear ODEs and PDEs, and nonlinear ODEs and certain\u0000nonlinear PDEs, with time-dependent coefficients.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138525264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tomislav Došlić, Mate Puljiz, Stjepan Šebek, Josip Žubrinić
{"title":"Rydberg atoms on a ladder","authors":"Tomislav Došlić, Mate Puljiz, Stjepan Šebek, Josip Žubrinić","doi":"arxiv-2312.02747","DOIUrl":"https://doi.org/arxiv-2312.02747","url":null,"abstract":"In this article, we study the dynamic variant and the equilibrium variant of\u0000the model of Rydberg atoms on a square ladder. In the dynamic case, we obtain\u0000the jamming limit for all values of $b ge 1$, where $b$ represents the\u0000so-called blockade range of a Rydberg atom. In the equilibrium case, we derive\u0000the complexity function for all values of $b ge 1$. By comparing these\u0000results, we highlight significant differences in the behavior of the two models\u0000as $b$ approaches infinity.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138521804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Upper tail large deviation for the one-dimensional frog model","authors":"Van Hao Can, Naoki Kubota, Shuta Nakajima","doi":"arxiv-2312.02745","DOIUrl":"https://doi.org/arxiv-2312.02745","url":null,"abstract":"In this paper, we study the upper tail large deviation for the\u0000one-dimensional frog model. In this model, sleeping and active frogs are\u0000assigned to vertices on $mathbb Z$. While sleeping frogs do not move, the\u0000active ones move as independent simple random walks and activate any sleeping\u0000frogs. The main object of interest in this model is the asymptotic behavior of\u0000the first passage time ${rm T}(0,n)$, which is the time needed to activate the\u0000frog at the vertex $n$, assuming there is only one active frog at $0$ at the\u0000beginning. While the law of large numbers and central limit theorems have been\u0000well established, the intricacies of large deviations remain elusive. Using\u0000renewal theory, B'erard and Ram'irez have pointed out a slowdown phenomenon\u0000where the probability that the first passage time ${rm T}(0,n)$ is\u0000significantly larger than its expectation decays sub-exponentially and lies\u0000between $exp(-n^{1/2+o(1)})$ and $exp(-n^{1/3+o(1)})$. In this article, using\u0000a novel covering process approach, we confirm that $1/2$ is the correct\u0000exponent, i.e., the rate of upper large deviations is given by $n^{1/2}$.\u0000Moreover, we obtain an explicit rate function that is characterized by\u0000properties of Brownian motion and is strictly concave.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138521805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mean square displacement of Brownian paths perturbed by bounded pair potentials","authors":"Volker Betz, Tobias Schmidt, Mark Sellke","doi":"arxiv-2312.02709","DOIUrl":"https://doi.org/arxiv-2312.02709","url":null,"abstract":"We study Brownian paths perturbed by semibounded pair potentials and prove\u0000upper bounds on the mean square displacement. As a technical tool we derive\u0000infinite dimensional versions of key inequalities that were first used in\u0000[Sellke; arXiv:2212.14023] in order to study the effective mass of the\u0000Fr\"ohlich polaron.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138521807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rafał Bistroń, Michał Eckstein, Shmuel Friedland, Tomasz Miller, Karol Życzkowski
{"title":"A new class of distances on complex projective spaces","authors":"Rafał Bistroń, Michał Eckstein, Shmuel Friedland, Tomasz Miller, Karol Życzkowski","doi":"arxiv-2312.02583","DOIUrl":"https://doi.org/arxiv-2312.02583","url":null,"abstract":"The complex projective space $mathbb{P}(mathbb{C}^n)$ can be interpreted as\u0000the space of all quantum pure states of size $n$. A distance on this space,\u0000interesting from the perspective of quantum physics, can be induced from a\u0000classical distance defined on the $n$-point probability simplex by the `earth\u0000mover problem'. We show that this construction leads to a quantity satisfying\u0000the triangle inequality, which yields a true distance on complex projective\u0000space belonging to the family of quantum $2$-Wasserstein distances.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138525265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A remark on certain restricted plane partitions and crystal melting model","authors":"Chenglang Yang","doi":"arxiv-2312.02749","DOIUrl":"https://doi.org/arxiv-2312.02749","url":null,"abstract":"In this paper, we provide formulas calculating the partition functions of two\u0000types of plane partitions using the crystal melting model method introduced by\u0000Okounkov, Reshetikhin and Vafa. As applications, we obtain a product formula\u0000for the partition function of the plane partitions with a limit shape boundary.\u0000A corollary of this formula is the demonstration of the equivalence between\u0000this partition function and the open-closed string amplitude of the\u0000double$-mathbb{P}^1$ model. We also derive a product formula for the partition\u0000function of symmetric plane partitions with a limit shape boundary.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138525271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integrable extensions of two-center Coulomb systems","authors":"Francisco Correa, Octavio Quintana","doi":"arxiv-2312.02013","DOIUrl":"https://doi.org/arxiv-2312.02013","url":null,"abstract":"In this paper, we investigate new integrable extensions of two-center Coulomb\u0000systems. We study the most general $n$-dimensional deformation of the\u0000two-center problem by adding arbitrary functions supporting second order\u0000commuting conserved quantities. The system is superintegrable for $n>4$ and,\u0000for certain choices of the arbitrary functions, reduces to known models\u0000previously discovered. Then, based on this extended system, we introduce an\u0000additional integrable generalisation involving Calogero interactions for $n=3$.\u0000In all examples, including the two-center problem, we explicitly present the\u0000complete list of Liouville integrals in terms of second-order integrals of\u0000motion.","PeriodicalId":501275,"journal":{"name":"arXiv - PHYS - Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138521726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}