Are heavy scalars natural in minimal supergravity?

TL;DR

The paper argues that large universal soft mass terms in minimal supergravity are not natural due to the need for fine-tuning, despite recent claims suggesting their naturalness near certain top quark mass values.

Contribution

It critically examines recent claims about the naturalness of large soft mass terms in minimal supergravity, highlighting the necessity of fine-tuning.

Findings

Large m_0 values require accidental cancellations

Fine-tuning is necessary for large m_0

Claims of naturalness are not supported by data or theory

Abstract

It has been recently claimed that very large values of a universal soft mass term m_0 for sfermions and higgs bosons become natural when M_top is close to 175 GeV if tan\beta\approx 10. We show that very large values of m_0 require accidental cancellations not guaranteed by experimental data or theoretical assumptions, and consequently an unnatural fine-tuning of the parameters.