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Johansson, K. & Viklund, F. (2026). Coulomb gas and the Grunsky operator on a Jordan domain with corners. Inventiones Mathematicae
Open this publication in new window or tab >>Coulomb gas and the Grunsky operator on a Jordan domain with corners
2026 (English)In: Inventiones Mathematicae, ISSN 0020-9910, E-ISSN 1432-1297Article in journal (Refereed) Published
Place, publisher, year, edition, pages
Springer Nature, 2026
National Category
Other Social Sciences not elsewhere specified
Identifiers
urn:nbn:se:kth:diva-382670 (URN)10.1007/s00222-026-01417-5 (DOI)001734664400001 ()2-s2.0-105035230111 (Scopus ID)
Note

QC 20260603

Available from: 2026-06-03 Created: 2026-06-03 Last updated: 2026-06-03Bibliographically approved
Courteaut, K. & Johansson, K. (2025). Partition function for the 2d Coulomb gas on a Jordan curve. Annales Fennici Mathematici, 50(1), 109-144
Open this publication in new window or tab >>Partition function for the 2d Coulomb gas on a Jordan curve
2025 (English)In: Annales Fennici Mathematici, ISSN 2737-0690, E-ISSN 2737-114X, Vol. 50, no 1, p. 109-144Article in journal (Refereed) Published
Abstract [en]

We prove an asymptotic formula for the partition function of a 2d Coulomb gas at inverse temperature beta > 0, confined to lie on a Jordan curve. The partition function can include a linear statistic. The asymptotic formula involves a Fredholm determinant related to the Loewner energy of the curve, and also an expression involving the sampling function, the exterior conformal map for the curve and the Grunsky operator. The asymptotic formula also gives a central limit theorem for linear statistics of the particles in the gas.

Place, publisher, year, edition, pages
Finnish Mathematical Society, 2025
Keywords
Log-gas, Coulomb gas, Jordan curve, partition function, free energy, Central Limit Theorem, global fluctuations, linear statistic
National Category
Mathematical sciences
Identifiers
urn:nbn:se:kth:diva-361871 (URN)10.54330/afm.159822 (DOI)001445841500003 ()2-s2.0-105001531220 (Scopus ID)
Note

QC 20250401

Available from: 2025-04-01 Created: 2025-04-01 Last updated: 2026-03-30Bibliographically approved
Courteaut, K., Johansson, K. & Lambert, G. (2024). From Berry–Esseen to super-exponential. Electronic Journal of Probability, 29, Article ID 11.
Open this publication in new window or tab >>From Berry–Esseen to super-exponential
2024 (English)In: Electronic Journal of Probability, E-ISSN 1083-6489, Vol. 29, article id 11Article in journal (Refereed) Published
Abstract [en]

For any integer m < n, where m can depend on n, we study the rate of convergence (Formula Presented) to its limiting Gaussian as n → ∞ for orthogonal, unitary and symplectic Haar distributed random matrices U of size n. In the unitary case, we prove that the total variation distance is less than (Formula Presented) times a constant. This result interpolates between the super-exponential bound obtained for fixed m and the 1/n bound coming from the Berry–Esseen theorem applicable when m ≥ n by a result of Rains. We obtain analogous results for the orthogonal and symplectic groups. In these cases, our total variation upper bound takes the form (Formula Presented) times a constant and the result holds provided n > 2m. For m = 1, we obtain complementary lower bounds and precise asymptotics for the L2-distances as n → ∞, which show how sharp our results are.

Place, publisher, year, edition, pages
Institute of Mathematical Statistics, 2024
Keywords
classical compact groups, Haar measure, Hankel determinants, rate of convergence, Toeplitz determinants
National Category
Mathematical Analysis
Identifiers
urn:nbn:se:kth:diva-344004 (URN)10.1214/23-EJP1068 (DOI)001165378300001 ()2-s2.0-85185324572 (Scopus ID)
Note

QC 20240229

Available from: 2024-02-28 Created: 2024-02-28 Last updated: 2025-12-05Bibliographically approved
Courteaut, K. & Johansson, K. (2024). Multivariate normal approximation for traces of orthogonal and symplectic matrices. Annales de l'I.H.P. Probabilites et statistiques, 60(1), 312-342
Open this publication in new window or tab >>Multivariate normal approximation for traces of orthogonal and symplectic matrices
2024 (English)In: Annales de l'I.H.P. Probabilites et statistiques, ISSN 0246-0203, E-ISSN 1778-7017, Vol. 60, no 1, p. 312-342Article in journal (Refereed) Published
Abstract [en]

We show that the distance in total variation between (Tr U, √12 Tr U2, . . ., √m Tr Um) and a real Gaussian vector, where 1 U is a Haar distributed orthogonal or symplectic matrix of size 2n or 2n + 1, is bounded by 「 (2 mn + 1)− 12 times a correction. The correction term is explicit and holds for all n ≥ m4, for m sufficiently large. For n ≥ m3 we obtain the bound (mn)−c √ mn with an explicit constant c. Our method of proof is based on an identity of Toeplitz + Hankel determinants due to Basor and Ehrhardt, see (Oper. Matrices 3 (2009) 167–86), which is also used to compute the joint moments of the traces.

Place, publisher, year, edition, pages
Institute of Mathematical Statistics, 2024
Keywords
Hankel determinants, Multivariate Gaussian approximation, Toeplitz determinants
National Category
Computational Mathematics
Identifiers
urn:nbn:se:kth:diva-344577 (URN)10.1214/22-AIHP1332 (DOI)001177499400007 ()2-s2.0-85186940639 (Scopus ID)
Note

QC 20240321

Available from: 2024-03-20 Created: 2024-03-20 Last updated: 2024-04-26Bibliographically approved
Johansson, K. & Mason, S. (2023). Dimer–Dimer Correlations at the Rough–Smooth Boundary. Communications in Mathematical Physics, 400(2), 1255-1315
Open this publication in new window or tab >>Dimer–Dimer Correlations at the Rough–Smooth Boundary
2023 (English)In: Communications in Mathematical Physics, ISSN 0010-3616, E-ISSN 1432-0916, Vol. 400, no 2, p. 1255-1315Article in journal (Refereed) Published
Abstract [en]

Three phases of macroscopic domains have been seen for large but finite periodic dimer models; these are known as the frozen, rough and smooth phases. The transition region between the frozen and rough region has received a lot of attention for the last twenty years and recently work has been underway to understand the rough–smooth transition region in the case of the two-periodic Aztec diamond. We compute uniform asymptotics for dimer–dimer correlations of the two-periodic Aztec diamond when the dimers lie in the rough–smooth transition region. These asymptotics rely on a formula found in Chhita and Johansson (Adv Math 294:37–149, 2016) for the inverse Kasteleyn matrix, they also apply to the infinite square grid dimer model with a variable weighting which interpolates between the rough and smooth phase (Kenyon et al. Ann Math (2) 163(3):1019–1056, 2006). In particular, we find that distant dimers initially decay exponentially when the magnetic coordinates are very close to the bounded complementary component of the associated amoebae, they then transition to a power law decay once far enough apart.

Place, publisher, year, edition, pages
Springer Nature, 2023
National Category
Mathematics
Identifiers
urn:nbn:se:kth:diva-332156 (URN)10.1007/s00220-023-04649-1 (DOI)000933131600002 ()2-s2.0-85147967451 (Scopus ID)
Note

QC 20230720

Available from: 2023-07-20 Created: 2023-07-20 Last updated: 2023-09-06Bibliographically approved
Ayyer, A., Chhita, S. & Johansson, K. (2023). Goe fluctuations for the maximum of the top path in alternating sign matrices. Duke mathematical journal, 172(10), 1961-2014
Open this publication in new window or tab >>Goe fluctuations for the maximum of the top path in alternating sign matrices
2023 (English)In: Duke mathematical journal, ISSN 0012-7094, E-ISSN 1547-7398, Vol. 172, no 10, p. 1961-2014Article in journal (Refereed) Published
Abstract [en]

The six-vertex model is an important toy-model in statistical mechanics for twodimensional ice with a natural parameter A. When A = 0, the so-called free-fermion point, the model is in natural correspondence with domino tilings of the Aztec diamond. Although this model is integrable for all A, there has been very little progress in understanding its statistics in the scaling limit for other values. In this work, we focus on the six-vertex model with domain wall boundary conditions at A = 1/2, where it corresponds to alternating sign matrices (ASMs). We consider the level lines in a height function representation of ASMs. We show that the maximum of the topmost level line for a uniformly random ASMs has the Gaussian orthogonal ensemble (GOE) Tracy-Widom distribution after appropriate rescaling. A key ingredient in our proof is Zeilberger's proof of the ASM conjecture. As far as we know, this is the first edge fluctuation result away from the tangency points for the domain-wall six-vertex model when we are not in the free-fermion case.

Place, publisher, year, edition, pages
Duke University Press, 2023
National Category
Probability Theory and Statistics
Identifiers
urn:nbn:se:kth:diva-336979 (URN)10.1215/00127094-2022-0075 (DOI)001047823100003 ()2-s2.0-85170501238 (Scopus ID)
Note

QC 20230922

Available from: 2023-09-22 Created: 2023-09-22 Last updated: 2023-10-03Bibliographically approved
Adler, M., Johansson, K. & van Moerbeke, P. (2022). A SINGULAR TOEPLITZ DETERMINANT AND THE DISCRETE TACNODE KERNEL FOR SKEW-AZTEC RECTANGLES. The Annals of Applied Probability, 32(2), 1234-1294
Open this publication in new window or tab >>A SINGULAR TOEPLITZ DETERMINANT AND THE DISCRETE TACNODE KERNEL FOR SKEW-AZTEC RECTANGLES
2022 (English)In: The Annals of Applied Probability, ISSN 1050-5164, E-ISSN 2168-8737, Vol. 32, no 2, p. 1234-1294Article in journal (Refereed) Published
Abstract [en]

Random tilings of geometrical shapes with dominos or lozenges have been a rich source of universal statistical distributions. This paper deals with domino tilings of checker board rectangular shapes such that the top two and bottom two adjacent squares have the same orientation and the two most left and two most right ones as well. It forces these so-called "skew-Aztec rectangles" to have cuts on either side. For large sizes of the domain and upon an appropriate scaling of the location of the cuts, one finds split tacnodes between liquid regions with two distinct adjacent frozen phases descending into the tacnode. Zooming about such split tacnodes, filaments appear between the liquid patches evolving in a bricklike sea of dimers of another type. This work shows that the random fluctuations in a neighborhood of the split tacnode are governed asymptotically by the discrete tacnode kernel, providing strong evidence that this kernel is a universal discrete-continuous limiting kernel occurring naturally whenever we have doubly interlacing patterns. The analysis involves the inversion of a singular Toeplitz matrix which leads to considerable difficulties.

Place, publisher, year, edition, pages
Institute of Mathematical Statistics, 2022
Keywords
Skew-Aztec rectangles, domino tilings, the discrete tacnode kernel, singular Toeplitz determinants
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering Discrete Mathematics
Identifiers
urn:nbn:se:kth:diva-312685 (URN)10.1214/21-AAP1708 (DOI)000791003700013 ()2-s2.0-85131623774 (Scopus ID)
Note

QC 20220524

Available from: 2022-05-24 Created: 2022-05-24 Last updated: 2023-03-07Bibliographically approved
Beffara, V., Chhita, S. & Johansson, K. (2022). LOCAL GEOMETRY OF THE ROUGH-SMOOTH INTERFACE IN THE TWO-PERIODIC AZTEC DIAMOND. The Annals of Applied Probability, 32(2), 974-1017
Open this publication in new window or tab >>LOCAL GEOMETRY OF THE ROUGH-SMOOTH INTERFACE IN THE TWO-PERIODIC AZTEC DIAMOND
2022 (English)In: The Annals of Applied Probability, ISSN 1050-5164, E-ISSN 2168-8737, Vol. 32, no 2, p. 974-1017Article in journal (Refereed) Published
Abstract [en]

Random tilings of the two-periodic Aztec diamond contain three macroscopic regions: frozen, where the tilings are deterministic; rough, where the correlations between dominoes decay polynomially; smooth, where the correlations between dominoes decay exponentially. In a previous paper, the authors found that a certain averaging of height function differences at the rough-smooth interface converged to the extended Airy kernel point process. In this paper, we augment the local geometrical picture at this interface by introducing well-defined lattice paths which are closely related to the level lines of the height function. We show, after suitable centering and rescaling, that a point process from these paths converge to the extended Airy kernel point process provided that the natural parameter associated to the two-periodic Aztec diamond is small enough.

Place, publisher, year, edition, pages
Institute of Mathematical Statistics, 2022
Keywords
Domino tilings, Airy kernel point process, two-periodic Aztec diamond
National Category
Discrete Mathematics
Identifiers
urn:nbn:se:kth:diva-312682 (URN)10.1214/21-AAP1701 (DOI)000791003700007 ()2-s2.0-85131623903 (Scopus ID)
Note

QC 20220524

Available from: 2022-05-24 Created: 2022-05-24 Last updated: 2023-03-07Bibliographically approved
Johansson, K. & Rahman, M. (2022). On inhomogeneous polynuclear growth. Annals of Probability, 50(2), 559-590
Open this publication in new window or tab >>On inhomogeneous polynuclear growth
2022 (English)In: Annals of Probability, ISSN 0091-1798, E-ISSN 2168-894X, Vol. 50, no 2, p. 559-590Article in journal (Refereed) Published
Abstract [en]

This article studies the inhomogeneous geometric polynuclear growth model; the distribution of which is related to Schur functions. We explain a method to derive its distribution functions in both space-like and time-like directions, focusing on the two-time distribution. Asymptotics of the two-time distribution in the KPZ-scaling limit is then considered, extending to two times several single-time distributions in the KPZ universality class.

Place, publisher, year, edition, pages
Institute of Mathematical Statistics, 2022
Keywords
KPZ universality, last passage percolation, polynuclear growth, two-time distribution
National Category
Probability Theory and Statistics
Identifiers
urn:nbn:se:kth:diva-311030 (URN)10.1214/21-AOP1540 (DOI)000773518500004 ()2-s2.0-85128868551 (Scopus ID)
Note

QC 20220421

Available from: 2022-04-21 Created: 2022-04-21 Last updated: 2022-06-25Bibliographically approved
Johansson, K. (2022). Strong Szegő Theorem on a Jordan Curve. In: Operator Theory: Advances and Applications (pp. 427-461). Springer Nature, 289
Open this publication in new window or tab >>Strong Szegő Theorem on a Jordan Curve
2022 (English)In: Operator Theory: Advances and Applications, Springer Nature , 2022, Vol. 289, p. 427-461Chapter in book (Other academic)
Abstract [en]

We consider certain determinants with respect to a sufficiently regular Jordan curve γ in the complex plane that generalize Toeplitz determinants which are obtained when the curve is the circle. This also corresponds to studying a planar Coulomb gas on the curve at inverse temperature β = 2. Under suitable assumptions on the curve we prove a strong Szegő type asymptotic formula as the size of the determinant grows. The resulting formula involves the Grunsky operator built from the Grunsky coefficients of the exterior mapping function for γ. As a consequence of our formula we obtain the asymptotics of the partition function for the Coulomb gas on the curve. This formula involves the Fredholm determinant of the absolute value squared of the Grunsky operator which equals, up to a multiplicative constant, the Loewner energy of the curve. Based on this we obtain a new characterization of curves with finite Loewner energy called Weil-Petersson quasicircles.

Place, publisher, year, edition, pages
Springer Nature, 2022
Keywords
Loewner energy, Strong Szegő theorem, Toeplitz determinant, Weil-Petersson quasicircle
National Category
Mathematics
Identifiers
urn:nbn:se:kth:diva-332170 (URN)10.1007/978-3-031-13851-5_19 (DOI)2-s2.0-85145867087 (Scopus ID)
Note

QC 20230721

Available from: 2023-07-21 Created: 2023-07-21 Last updated: 2023-09-06Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-2943-7006

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