Project A2
The hierarchy, fine-tuning and naturalness problem
from a philosophical perspective

The hierarchy, fine-tuning and naturalness problem from a philosophical perspective

Over the last few decades, the naturalness principle (on one common formulation, the wish that certain parameters in fundamental physics do not require fine-tuning) has been one of the main motivations for physicists to develop alternatives to the Standard Model of elementary particle physics. The goal of this project is to analyze the conceptual origins of the naturalness principle and assess its status as a guiding principle in the construction of theories. In Phase 1 of the project, we identified several points of weakness in the motivations for the naturalness principle and called into question its purported successful applications, such as the prediction of the charm quark mass. In Phase 2, we are going to analyze to what extent and in which form the attitude of physicists towards the naturalness concept has changed in the light of the lack of any conclusive signs for New Physics at the LHC. We further intend to more deeply explore the connection of naturalness to the foundations of renormalization theory and issues of reduction and emergence, and to consider applications of naturalness in other areas of physics, including the cosmological constant problem and the strong-CP problem.

 

A workshop on naturalness was hosted by the Institute of Theoretical Particle Physics and Cosmology at RWTH Aachen University on Feb 28-Mar 2 2018.

 

Principal Investigators:
Robert Harlander
Radin Dardashti

 

Doctoral Researcher:
N. N.

 

Previous Member:
Gregor Schiemann (former PI)
Miguel Ángel Carretero Sahuquillo (former doctoral researcher)
Joshua Rosaler
Enno Fischer

James D. Fraser (former postdoctoral researcher)

 

Relevant Publications

Joshua Rosaler, "Dogmas of Effective Field Theory: Scheme Dependence, Fundamental Parameters, and the Many Faces of the Higgs Naturalness Principle”, Found. Phys. 52, 2 (2022). https://doi.org/10.1007/s10701-021-00510-4

 

Enno Fischer, "Naturalness and the Forward-Looking Justification of Scientific Principles”, accepted for publication in Philosophy of Science 
 

Sahuquillo, M. Á. C. (2019). The charm quark as a naturalness success. Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, 68, 51-61.

 

Harlander R. & Rosaler, J. (2019). Higgs Naturalness and Renormalized Parameters. Foundations of Physics, 49(9), 879-897.

 

Rosaler, J., & Harlander, R. (2019). Naturalness, Wilsonian renormalization, and “fundamental parameters” in quantum field theory. Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, 66, 118-134.