Infrared aspects of spontaneous symmetry breaking of gauge theories in two and three dimensions

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5944773

Cho, H T

The spontaneous chiral symmetry breaking in SU(N) quantum chromodynamics (QCD) in two dimensions is investigated by calculating the order parameter , where psi is the fermion in the theory, in the authors approximation. In the chiral limit, where the mass of the fermion m ..-->.. O, is found to be non-zero both in the finite N and N ..-->.. infinity cases. This implies that chiral symmetry is spontaneously broken by infrared effects in all these cases. The Wilson loop expectation value is calculated for again SU(N) QCD in two dimensions, without fermions. In two dimensions, the Coulomb potential is linear, and thus confining. Under the authors approximation, the area law of the Wilson loop is indeed obtained as expected, for all values of N; in addition, the N-dependent polynomial multiplying the Wilson exponential is also obtained. In quantum electrodynamics (QED) in three dimensions there is a possibility of spontaneous breaking of parity. The authors consider this possibility by studying and the photon propagator. It is found that in the limit m ..-->.. O, is zero and the photon has a zero mass pole. Therefore, there is no sign of spontaneous parity violation in (QED) in three dimensions induced by infrared effects, in contrast to the positive result of chiral symmetry breaking in two dimensions.

• Research Organization: Brown Univ., Providence, RI (USA)
• OSTI ID: 5944773
• Country of Publication: United States
• Language: English

Related Subjects

645400* -- High Energy Physics-- Field Theory
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHIRAL SYMMETRY
ELECTRODYNAMICS
ELEMENTARY PARTICLES
EXPECTATION VALUE
FERMIONS
FIELD THEORIES
INFRARED DIVERGENCES
LIE GROUPS
MASS
MASSLESS PARTICLES
ORDER PARAMETERS
PHOTONS
PROPAGATOR
QUANTUM CHROMODYNAMICS
QUANTUM ELECTRODYNAMICS
QUANTUM FIELD THEORY
REST MASS
SU GROUPS
SYMMETRY
SYMMETRY BREAKING
SYMMETRY GROUPS
THREE-DIMENSIONAL CALCULATIONS
TWO-DIMENSIONAL CALCULATIONS
WILSON LOOP