Gaussian beta ensembles: the perfect freezing transition and its characterization in terms of Beurling-Landau densities
Fuente:
arXiv
Salvato in:
| Autori principali: | , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2022
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866916364512395264 |
|---|---|
| author | Ameur, Yacin Marceca, Felipe Romero, José Luis |
| author_facet | Ameur, Yacin Marceca, Felipe Romero, José Luis |
| contents | The Gaussian $β$-ensemble is a real $n$-point configuration $\{x_j\}_1^n$ picked randomly with respect to the Boltzmann factor $e^{-\fracβ2H_n}$, $H_n=\sum_{i\ne j}\log\frac 1{|x_i-x_j|}+n\sum_{i=1}^n\tfrac 12x_i^2.$ The point process $\{x_j\}_1^n$ tends to follow the semicircle law $σ(x)=\tfrac 1{2π}\sqrt{(4-x^2)_+}$ in certain average senses.
A Fekete configuration (minimizer of $H_n$) is spread out in a much more uniform way in the interval $[-2,2]$ with respect to the regularization $σ_n(x)=\max\{σ(x),n^{-\frac 1 3}\}$ of the semicircle law. In particular, Fekete configurations are "equidistributed" with respect to $σ_n(x)$, in a certain technical sense of Beurling-Landau densities.
We consider the problem of characterizing sequences $β_n$ of inverse temperatures, which guarantee almost sure equidistribution as $n\to\infty$. We find that a necessary and sufficient condition is that $β_n$ grows at least logarithmically in $n$: $$β_n\gtrsim \log n.$$ We call this growth rate the perfect freezing regime. We give several further results on the distribution of particles when $β_n\gtrsim\log n$, for example on minimal spacing, discrepancies, and sampling and interpolation for weighted polynomials.
The condition $β_n\gtrsim\log n$ was introduced by some of the authors in the context of two-dimensional Coulomb gas ensembles, where it is shown to be sufficient for equidistribution. Although the technical implementation requires some considerable modifications, the strategy from dimension two adapts well to prove sufficiency also for one-dimensional Gaussian ensembles. On a technical level, we use estimates for weighted polynomials due to Levin, Lubinsky, Gustavsson and others. The other direction (necessity) involves estimates due to Ledoux and Rider on the distribution of particles which fall near or outside the boundary. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2205_15054 |
| institution | arXiv |
| publishDate | 2022 |
| record_format | arxiv |
| spellingShingle | Gaussian beta ensembles: the perfect freezing transition and its characterization in terms of Beurling-Landau densities Ameur, Yacin Marceca, Felipe Romero, José Luis Probability Mathematical Physics Complex Variables 60K35, 82B26, 94A20, 31C20 The Gaussian $β$-ensemble is a real $n$-point configuration $\{x_j\}_1^n$ picked randomly with respect to the Boltzmann factor $e^{-\fracβ2H_n}$, $H_n=\sum_{i\ne j}\log\frac 1{|x_i-x_j|}+n\sum_{i=1}^n\tfrac 12x_i^2.$ The point process $\{x_j\}_1^n$ tends to follow the semicircle law $σ(x)=\tfrac 1{2π}\sqrt{(4-x^2)_+}$ in certain average senses. A Fekete configuration (minimizer of $H_n$) is spread out in a much more uniform way in the interval $[-2,2]$ with respect to the regularization $σ_n(x)=\max\{σ(x),n^{-\frac 1 3}\}$ of the semicircle law. In particular, Fekete configurations are "equidistributed" with respect to $σ_n(x)$, in a certain technical sense of Beurling-Landau densities. We consider the problem of characterizing sequences $β_n$ of inverse temperatures, which guarantee almost sure equidistribution as $n\to\infty$. We find that a necessary and sufficient condition is that $β_n$ grows at least logarithmically in $n$: $$β_n\gtrsim \log n.$$ We call this growth rate the perfect freezing regime. We give several further results on the distribution of particles when $β_n\gtrsim\log n$, for example on minimal spacing, discrepancies, and sampling and interpolation for weighted polynomials. The condition $β_n\gtrsim\log n$ was introduced by some of the authors in the context of two-dimensional Coulomb gas ensembles, where it is shown to be sufficient for equidistribution. Although the technical implementation requires some considerable modifications, the strategy from dimension two adapts well to prove sufficiency also for one-dimensional Gaussian ensembles. On a technical level, we use estimates for weighted polynomials due to Levin, Lubinsky, Gustavsson and others. The other direction (necessity) involves estimates due to Ledoux and Rider on the distribution of particles which fall near or outside the boundary. |
| title | Gaussian beta ensembles: the perfect freezing transition and its characterization in terms of Beurling-Landau densities |
| topic | Probability Mathematical Physics Complex Variables 60K35, 82B26, 94A20, 31C20 |
| url | https://arxiv.org/abs/2205.15054 |