Codebase Structure

Description of the general organization and core functions within Warp Factory

Warp Factory is a package of functions written in MATLAB. It is organized around several modules containing functions that can be called to build and evaluate metrics. Each of these modules will be described here at a high level.

Module Descriptions

Metrics

The Metrics Module provides functions for uses to build spacetimes. The following functions are currently provided:

Function	Description
setMinkowski	Generates a flat spacetime as a 4x4 cell object.
setMinkowskiThreePlusOne	Generates the 3+1 components for flat spacetime..
threePlusOneBuilder	Generates the standard metric tensor from the 3+1 components.
threePlusOneDecomposer	Generates the 3+1 components from a standard metric tensor.

In addition, a standard Metric Library is provided which contains some of the standard and famous warp metrics found over the last few decades. These include:

Standard Metric	Description
metricGet_Minkowski	Generic flat spacetime.
metricGet_Alcubierre	The Alcubierre solution. Includes comoving frame.
metricGet_Lentz	The Lentz soliton solution. Includes comoving frame.
metricGet_VanDenBroeck	The Van Den Broeck modification to Alcubierre. Includes comoving frame.
metricGet_ModifiedTime	Bobrick and Martire modified time version of the Alcubierre metric. Includes comoving frame.
metricGet_Schwarzschild	Standard black hole solution.

Supporting these main functions are several auxiliary functions that can be found within the utils folder in Metrics > utils.

Analyzer

The Analyzer Module performs all of the analysis products provided in Warp Factory. This includes things like finding the energy conditions from a stress-energy tensor or determining the metric scalars. The following functions are currently provided:

Function	Description
getMomentumFlowLines	Generates momentum flowlines from the stress-energy tensor.
doFrameTransfer	Performs transformations to tensors. Currently only does a local Eulerian transformation.
changeTensorIndex	Performs raising or lowering operations on tensors
getScalars	Finds metric scalars
getEnergyConditions	Finds the energy conditions of the stress-energy tensor
evalMetric	Evaluates the metric and returns the stress-energy, scalars, and energy conditions

Supporting these main functions are several auxiliary functions that can be found within the utils folder in Analyzer > utils.

Solver

The Solver Module evaluates the field equation to find the stress-energy tensor. The following functions are currently provided:

Function	Description
getEnergyTensor	Finds the stress-energy tensor from the metric tensor
verifyTensor	Checks the data fields of tensor objects for completeness.

Supporting this main function are several auxiliary functions that can be found within the utils folder in Solver > utils.

Visualizer

The Visualizer Module has several functions which aid users in displaying the tensors and analysis products. This currently includes the following:

Function	Description
plotThreePlusOne	Plots the metric in terms of its 3+1 foliation components
plotTensor	Plots the components of the tensor objects

Supporting these main functions are several auxiliary functions that can be found within the utils folder in Visualizer > utils. described in Plot Functions

Units

The Units Module contains a list of reserved function names that act as unit specifications for use in Warp Factory.