de
en
Schliessen
Detailsuche
Bibliotheken
Projekt
Impressum
Datenschutz
zum Inhalt
Detailsuche
Schnellsuche:
OK
Ergebnisliste
Titel
Titel
Inhalt
Inhalt
Seite
Seite
Im Dokument suchen
Bogner, Thorsten: Density matrix renormalisation applied to nonlinear dynamical systems. 2007
Inhalt
1 Introduction
Outline of the thesis
2 Linear Matrix Decompositions
2.1 Diagonalisation of a Matrix
2.2 Singular Value Decomposition
2.3 Orthogonal Projections
2.4 Gram-Schmidt Orthonormalisation
2.5 The LU Decomposition
2.5.1 Matrix Inversion by LU Decomposition
2.6 Determinant of a Matrix and Characteristic Polynomial
2.7 Inverse and Pseudo-inverse of a Matrix
2.8 The QR decomposition
2.9 The Schur decomposition
2.9.1 Ordering of the Schur decomposition
3 Partial Differential Equations
3.1 Classifications
3.2 Method of characteristics
3.3 Linearity
3.4 Well posed problems
3.5 Numerical Treatment
3.5.1 Integration of ODEs
3.5.2 Finite differencing for PDEs
Boundary conditions
Matrix notation
Boundary conditions and Matrix notation
3.5.3 Finite Element Methods for PDEs
Galerkin Methods
Implementation of Boundary Conditions
3.5.4 Spectral Methods
Boundary conditions
Derivation
4 Master Equation Description
Dimensionality versus Linearity
Stochasticity from Missing Information
Time Evolution
4.1 Constructing the Master Operator
Source and Sink Operator
Diffusion Operator
Annihilation Operator
4.1.1 Probability Conservation and Steady State
5 Dynamical Systems and Model Reduction
5.1 Problem Setup
Linear Systems
Time Discrete Systems
5.2 Model Reduction
5.2.1 Choice of error functional
5.2.2 Reduced Model
5.2.3 Linear Projection
5.2.4 Nonlinear Reductions
5.2.5 Optimal Model Reduction for Linear Dynamics
5.2.6 Optimising Model Reduction for Nonlinear Dynamics
Linearisation
Minimisation Approach
5.2.7 Proper Orthogonal Decomposition
6 Density Matrix Renormalisation Group
6.1 Infinite System Method
6.2 Finite System Iteration
6.3 Reconstruction of States
6.4 Single Particle vs. Many Particle DMRG
Single Particle Systems
Many Body Systems
7 Proposed Methods
7.1 Real Schur DMRG
7.1.1 Technical Implementation
7.2 Proper Orthogonal Decomposition DMRG
7.2.1 Technical Implementation
7.3 General Variational Method for Proper Orthogonal Decomposition
7.3.1 Technical Implementation
7.3.2 Spectral variant
8 Microscopic Models
8.1 Reaction Diffusion System
8.1.1 Numerical Results
Normalisation of the Results
Average Density Profile
Nearest Neighbour Density Correlation
8.2 Surface Deposition Model
Continuous Equation
Microscopic Model
-Model
-Model
8.2.1 Numerical Results
Normalisation of the Results
Average Surface Step Size
Correlation of Surface Steps
8.2.2 POD results
Stochastic Simulation
Simulation of the KPZ Equation
9 Proper Orthogonal Decomposition DMRG
9.1 The Linear Diffusion Equation
9.2 The Burgers Equation
9.3 Nonlinear Diffusion
9.4 Computational Load
10 General Variational Method for Proper Orthogonal Decomposition
10.1 Flow Problems
10.1.1 Navier Stokes Equations and 2D Flows
10.2 Model Problem
10.3 Numerical Integration
10.4 Numerical Results
Snapshots of the Flow
10.4.1 Comparing the Accuracy
Effect of the Reynolds Number
Effects of the Sweeps
Effects of Different Numbers of Retained States
Effect of the Spatial Resolution
Variational POD versus the Spectral Variant
Evaluation of the Relative Error
Visualisation of the POD and V-POD Modes
Visualisation of the Error Evolution
11 Conclusions
11.1 Schur DMRG
Future Prospects
11.2 POD DMRG
Future Prospects
11.3 Variational POD
Future Prospects
A Finite Numerical Precision
Fixed-Point Representation
Floating-Point Representation
Stability
B Optimal Reduction of Linear Systems
B.1 Long Time Optimised Projection
B.2 Short Time Optimised Projection
C Ordering of the Schur Decomposition
D Mathematical Addenda
D.1 Basic notation
D.1.1 Fields
D.1.2 Vectors
D.2 Vector Space Axioms
D.2.1 Scalar product, Norm
D.2.2 Basis
D.2.3 Subspaces
D.2.4 Linear Transformations, Matrixes
Range, Kernel and Rank
D.2.5 Tensors