Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mass Hierarchy and Vacuum Energy   A hierarchically small weak scale does not generally coincide with enhanced
symmetry, but it may still be exceptional with respect to vacuum energy. By
analyzing the classical vacuum energy as a function of parameters such as the
Higgs mass, we show how near-criticality, i.e. fine-tuning, corresponds
universally to boundaries where the vacuum energy transitions from exactly flat
to concave down. In the presence of quantum corrections, these boundary regions
can easily be perturbed to become maxima of the vacuum energy. After
introducing a dynamical scalar field $\phi$ which scans the Higgs sector
parameters, we propose several possible mechanisms by which this field could be
localized to the maximum. One possibility is that the $\phi$ potential has many
vacua, with those near the maximum vacuum energy expanding faster during a long
period of cosmic inflation and hence dominating the volume of the Universe.
Alternately, we describe scenarios in which vacua near the maximum could be
anthropically favored, due to selection of the late-time cosmological constant
or dark matter density. Independent of these specific approaches, the physical
value of the weak scale in our proposal is generated naturally and dynamically
from loops of heavy states coupled to the Higgs. These states are predicted to
be a loop factor heavier than in models without this mechanism, avoiding
tension with experimental null results.

6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs