activity
20242026
collaborators

6 papers

physics.comp-ph2026

Parallelized contraction of tensor trains or matrix product operators

Simone FoderÃ, Marc K. Ritter, Hiroshi Shinaoka +1

Tensor Trains (TT), also known as Matrix Product States (MPS) and Matrix Product Operators (MPO), provide a compact and structured representation for high-dimensional data and oper…

math.NA2026

Fast elementwise operations on tensor trains with alternating cross interpolation

Marc K. Ritter

Tensor trains (TTs), also known as matrix product states (MPS), are compressed representations of high-dimensional data that can be efficiently manipulated to perform calculations…

physics.comp-ph2026

Adaptive Patching for Tensor Train Computations

Gianluca Grosso, Marc K. Ritter, Stefan Rohshap +5

Quantics Tensor Train (QTT) operations such as matrix product operator contractions are prohibitively expensive for large bond dimensions. We propose an adaptive patching scheme th…

cond-mat.str-el2025

Compressing local vertex functions from the multipoint numerical renormalization group using quantics tensor cross interpolation

Markus Frankenbach, Marc Ritter, Mathias Pelz +3

The multipoint numerical renormalization group (mpNRG) is a powerful impurity solver that provides accurate spectral data useful for computing local, dynamic correlation functions…

cond-mat.str-el2025

Two-particle calculations with quantics tensor trains: Solving the parquet equations

Stefan Rohshap, Marc K. Ritter, Hiroshi Shinaoka +3

We present the first application of quantics tensor trains (QTTs) and tensor cross interpolation (TCI) to the solution of a full set of self-consistent equations for multivariate f…

physics.comp-ph2024

Learning tensor networks with tensor cross interpolation: new algorithms and libraries

Yuriel Núñez Fernández, Marc K. Ritter, Matthieu Jeannin +8

The tensor cross interpolation (TCI) algorithm is a rank-revealing algorithm for decomposing low-rank, high-dimensional tensors into tensor trains/matrix product states (MPS). TCI…