“Sloppy” nuclear energy density functionals: Effective model reduction

Scientific paper - Original scientific paper

• Author: Tamara Nikšić; MBZ: 234533
• Author: Dario Vretenar; MBZ: 9570
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

Concepts from information geometry are used to analyze parameter sensitivity for a nuclear energy density functional, representative of a class of semiempirical functionals that start from a microscopically motivated ansatz for the density dependence of the energy of a system of protons and neutrons. It is shown that such functionals are “sloppy, ” namely, characterized by an exponential range of sensitivity to parameter variations. Responsive to only a few stiff parameter combinations, sloppy functionals exhibit an exponential decrease of sensitivity to variations of the remaining soft parameters. By interpreting the space of model predictions as a manifold embedded in the data space, with the parameters of the functional as coordinates on the manifold, it is also shown that the exponential distribution of model manifold widths corresponds to the range of parameter sensitivity. Using the manifold boundary approximation method, we illustrate how to systematically construct effective nuclear density functionals of successively lower dimension in parameter space until sloppiness is eventually eliminated and the resulting functional contains only stiff combinations of parameters.

• Keywords (english): nuclear energy density functions; information geometry; manifold boundary approximation method
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review C
• Numbering: vol. 94, no. 2, 024333
• p-ISSN: 2469-9985
• DOI: https://doi.org/10.1103/PhysRevC.94.024333
• URN:NBN: urn:nbn:hr:217:392049
• Publication: 2016
• Project: Number: IP-2014-09-9159; Title (croatian): Struktura i dinamika egzotičnih femto-sustava; Acronym: STRUDEF; Leader: Nils Paar; Jurisdiction: Croatia; Funding stream: IP
• Document URL: https://journals.aps.org/prc/abstract/10.1103/PhysRevC.94.024333
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2016 American Physical Society. Received 28 June 2016; published 24 August 2016.
• Created on: 2020-02-23 19:21:50