Related papers: Is Symmetry Breaking into Special Subgroup Special…
Dynamical symmetry breaking is investigated for a four-fermion Nambu-Jona-Lasinio model in external electromagnetic and gravitational fields. An effective potential is calculated in the leading order of the large-N expansion using the…
In this paper we consider the problem of spontaneous supersymmetry breaking in $N=4$ supergravity interacting with vector multiplets. We start with the ordinary version of such model with the scalar field geometry $SU(1,1)/U(1)\otimes…
We investigate the phenomenology of an orbifold string model in which supersymmetry breaking is dominated by the overall `size' modulus field and all matter fields are in the untwisted sector. The possibly close degeneracy of the lightest…
We have shown that in a large number of generic and renormalizable Wess-Zumino models existence of a $Z_n$ R-symmetry is sufficient to break supersymmetry spontaneously. This implies that existence of a $Z_n$ R-symmetry is a necessary…
Chiral symmetry breaking in the Nambu-Jona-Lasinio model in a constant magnetic field is studied in spacetimes of dimension D > 4. It is shown that a constant magnetic field can be characterized by [(D-1)/2] parameters. For the maximal…
It is conjectured that flavor mixing furnishes a universal mechanism for the spontaneous breaking of supersymmetry. The conjecture is proved explicitly for the mixing of two Wess--Zumino $\mathcal{N}=1$ supermultiplets and arguments for its…
We address the question of supersymmetry breaking of a higher dimensional supersymmetric theory due to coset space dimensional reduction. In particular we study a ten-dimensional supersymmetric $E_{8}$ gauge theory which is reduced over all…
We discuss why the SU(3)^3 supersymmetric model with the most general superpotential can naturally break to the standard model if gauge singlets and a discrete symmetry are included. This mechanism does away with the need for fine-tuning in…
We study the phase diagram of the two-dimensional N=1 Wess-Zumino model on the lattice using Wilson fermions and the fermion loop formulation. We give a complete nonperturbative determination of the ground state structure in the continuum…
We consider supersymmetric SO(10) grand unification where the unified gauge group can break to the Standard Model gauge group through different chains. The breaking of SO(10) necessarily involves the reduction of the rank, and consequent…
The discovery of spontaneous symmetry breaking in particle physics was the greatest contribution in Nambu's achievements. There is another class of symmetries that exist in the low energy nature, yet is doomed to be broken at high energy,…
If supersymmetry turns out to be a symmetry of nature at low energies, the first order of business to measure the soft breaking parameters. But one will also want to understand the symmetry, and its breaking, more microscopically. Two…
It is shown that supersymmetry is spontaneously broken in certain three-dimensional supersymmetric gauge theories, by using the s-rule in their string theory realization as brane configurations. In particular, supersymmetry is broken in N=3…
We study the supersymmetric GUT models where the supersymmetry and GUT gauge symmetry can be broken by the discrete symmetry. First, with the ansatz that there exist discrete symmetries in the branes' neighborhoods, we discuss the general…
We study gauge symmetry breaking patterns in supersymmetric gauge models defined on $M^4\times S^1$. Instead of utilizing the Scherk-Schwarz mechanism, supersymmetry is broken by bare mass terms for gaugino and squarks. Though the matter…
The concepts of symmetry and its breakdown are investigated in two different terms according to whether the resulting asymmetry is universal or only obtained for a special configuration: we shall illustrate this by considering in the first…
We analyze dynamics of chiral gauge theories based on the $SU(N)$ gauge group with one anti-symmetric tensor $A$ and $(N-4)$ anti-fundamentals $F_{i}$ when $N$ is odd. Based on the continuity to the supersymmetric gauge theories with…
We propose a new mechanism of spontaneous supersymmetry breaking in noncommutative gauge theories. We find that in N=1 noncommutative gauge theories both supersymmetry and gauge invariance are dynamically broken. Supersymmetry is broken…
I consider the superfield derivation of the effective theory of softly broken supersymmetry below the GUT scale. I point out the role of supergauge invariance in determining the form of the result, which is rather restricted in interesting…
We review the subject of spontaneous supersymmetry breaking. First we consider supersymmetry breaking in a semiclassical theory. We illustrate it with several examples, demonstrating different phenomena, including metastable supersymmetry…