Gauge Fields and Matter Fields Localized on Walls 

Norisuke Sakai
Research and Education Center for Natural Sciences, 
Keio University, 


abstract: 

Brane-world scenario presupposes localization of The Standard 
Model particles on a brane. 
It has been difficult to localize non-Abelian gauge fields 
on branes such as domain walls. 
In Ref.1, we have proposed a mechanism using the field-dependent 
gauge coupling which gives a position-dependent gauge coupling 
when domain wall solution is constructed. 
With the appropriate position-dependent gauge coupling, we 
can localize non-Abelian gauge fields on domain walls in 
five-dimensional space-time. 
Low-energy effective theory posseses a massless vector 
field, and a mass gap. 
The four-dimensional gauge invariance is maintained intact. 

In order to localize massless matter fields in nontrivial 
representations of the gauge group, we introduce fields 
with a global symmetry, as in Ref.2. 
In Ref.3, we have successfully identified a subgroup of the 
global symmetry as the gauge group whose gauge fields are 
localized on the wall. 
Both non-Abelian gauge fields and minimally interacting 
massless matter fields are localized on a domain wall in the 
five-dimensional spacetime. 

In Ref.4, an economical field content allows us to eliminate 
a moduli for a instability, and to demonstrate the positivity 
of the position-dependent coupling in the entire moduli space. 
Effective Lagrangian similar to the chiral Lagrangian is 
found with a new feature of different coupling strengths 
for adjoint and singlet matter that depend on the width 
of the domain wall. 

Our result provides a step towards a realistic model building 
of brane-world scenario using topological solitons. 


References: 
1.Prog.Theor.Phys. 124-71 (2010),Ohta and Sakai, ``Non-Abelain 
Gauge Field Localized on Walls with Four-Dimensional World Volume''
2.Phys.Rev.77-125008 (2008), Eto, Fujimori, Nitta, Ohashi, and Sakai,
``Domain walls with non-Abelian clouds''
3.Prog.Theor.Exp.Phys. 2013-013B05 (2013), Arai, Blaschke, Eto, and Sakai
``Matter Fields and non-Abelain Gauge Fields Localized on Walls''
4.Prog.Theor.Exp.Phys. 2013-0903B01 (2013), Arai, Blaschke, Eto, and Sakai
``Stabilizing Matter and Gauge Fields Localized on Walls''