Inflatox - multifield inflation consistency conditions in python

Inflatox provides a framework to implement high-performance numerical consistency conditions for multifield inflation models. As an example, an implementation of the potential consistency condition for slow-roll rapid-turn two-field inflation from Anguelova & Lazaroiu (2023)[^1] is built right into the package.

Features

• symbolic solver for components of the Hesse matrix of an inflationary model with non-canonical kinetic terms, powered by sympy.
• transpiler (with bindings to the platform-native C compiler) to transform sympy expressions into executable compiled code
• built-in multithreaded rust module for high-performance calculations of consistency conditions that interfaces directly with numpy and python.
• no need to read, write or compile any rust or C code manually (this is all done automatically behind the scenes)

Installation and Dependencies

If you want to use the inflatox package and do not want to add your own native code to it, installing the inflatox python package is sufficient.

• The inflatox python package can be installed by running the pip install inflatox command.

If you would like to extend inflatox with your own native rust code, this can be achieved by extending the inflatox rust crate:

• The inflatox rust crate can added to your rust project by adding it to your Cargo.toml as a dependency like so:

[dependencies]
inflatox = "0.1"

Example programme

for more examples, see the notebooks folder

The following code example shows how inflatox can be used to calculate the potential and components of the Hesse matrix for a two-field hyperinflation model.

#import inflatox
import inflatox
import sympy as sp
import numpy as np
sp.init_printing()

#define model
φ, θ, L, m, φ0 = sp.symbols('φ θ L m φ0')
fields = [φ, θ]

V = (1/2*m**2*(φ-φ0)**2).nsimplify()
g = [
  [1, 0],
  [0, L**2 * sp.sinh(φ/L)**2]
]

display(g, V)

#symbolic calculation
calc = inflatox.SymbolicCalculation.new_from_list(fields, g, V)
hesse = calc.execute([[0,1]])

#run the compiler
out = inflatox.Compiler(hesse).compile()

#evaluate the compiled potential and Hesse matrix
from inflatox.consistency_conditions import AnguelovaLazaroiuCondition
anguelova = AnguelovaLazaroiuCondition(out)

args = np.array([1.0, 1.0, 1.0])
x = np.array([2.0, 2.0])
print(anguelova.calc_V(x, args))
print(anguelova.calc_H(x, args))

License

Inflatox is explicitly not licensed under the dual Apache/MIT license common to the Rust ecosystem. Instead it is licensed under the terms of the European Union Public License v1.2.

Inflatox is a science project and embraces the values of open science and free and open software. Closed and paid scientific software suites hinder the development of new technologies and research methods, as well as diverting much- needed public funds away from researchers to large publishing and software companies.

See the LICENSE.md file for the EUPL text in all 22 official languages of the EU, and LICENSE-EN.txt for a plain text English version of the license.

References

[^1]: Anguelova, L., & Lazaroiu, C. (2023). Dynamical consistency conditions for rapid turn inflation. Journal of Cosmology and Astroparticle Physics, May 2023(20). https://doi.org/10.1088/1475-7516/2023/ 05/020