Browsing by Author "YAJNIK, UA"
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BL cosmic strings and baryogenesis
BHATTACHARJEE, P; SAHU, N; YAJNIK, UA (AMERICAN PHYSICAL SOC, 2004)Cosmic strings arising from breaking of the U(1)(BL) gauge symmetry that occurs in a wide variety of unified models can carry zero modes of heavy Majorana neutrinos. Decaying and/or repeatedly selfinteracting closed loops ... 
Baryogenesis
YAJNIK, UA (INDIAN ACADEMY SCIENCES, 2000)Developments in understanding of baryogenesis are reviewed. We start with early motivations and the proposals in the context of GUTs. Next, the importance of the sphaleron solution and its implications are discussed. Studies ... 
Baryogenesis via leptogenesis in presence of cosmic strings
SAHU, N; BHATTACHARJEE, P; YAJNIK, UA (ELSEVIER SCIENCE BV, 2006)We study the effect on leptogenesis due to BL cosmic strings of a U(1)(BL) extension of the Standard Model. The disappearance of closed loops of BL cosmic strings can produce heavy right handed neutrinos, NR's, whose ... 
Battle of the bulge: Decay of the thin, false cosmic string
LEE, BH; LEE, W; MACKENZIE, R; PARANJAPE, MB; YAJNIK, UA; YEOM, DH (AMER PHYSICAL SOC, 2013)We consider the decay of cosmic strings that are trapped in the false vacuum in a theory of scalar electrodynamics in 3 + 1 dimensions. This paper is the 3 + 1dimensional generalization of the 2 + 1dimensional decay of ... 
Black hole area quantization
DAS, S; RAMADEVI, P; YAJNIK, UA (WORLD SCIENTIFIC PUBL CO PTE LTD, 2002)It has been argued by several authors that the quantum mechanical spectrum of black hole horizon area must be discrete. This has been confirmed in different formalisms, using different approaches. Here we concentrate on ... 
Bubble wall dynamics, generalized yukawa couplings and adequate electroweak baryogenesis in twoHiggsdoublet model
DUARI, SB; YAJNIK, UA (WORLD SCIENTIFIC PUBL CO PTE LTD, 1996)Baryogenesis at the electroweak scale depends on bubble wall dynamics and particle physics. We trace the dynamics of the relative phase during bubble formation in twoHiggsdoublet model (2HDM) and compute its contribution ... 
Canonical quantization inside the Schwarzschild black hole
YAJNIK, UA; NARAYAN, K (IOP PUBLISHING LTD, 1998)We propose a scheme for quantizing a scalar field over the Schwarzschild manifold including the interior of the horizon. On the exterior, the timelike Killing vector and on the horizon the isometry corresponding to restricted ... 
COSMIC STRINGS AT THE ELECTROWEAK PHASETRANSITION
DUARI, SB; YAJNIK, UA (ELSEVIER SCIENCE BV, 1994)If cosmic strings are present at the electroweak phase transition, they can act as seeds on which bubbles of true vacuum nucleate. We explore the nature of such a phase transition, in particular the wall velocity and ... 
Cosmic strings at the electroweak phasetransition  an application
DUARI, SB; YAJNIK, UA (ELSEVIER SCIENCE BV, 1995)We consider the phase transition in the electroweak theory with two Higgs doublets in the presence of preexisting cosmic strings. The correction to the effective action coming from the triangle diagram consisting of one ... 
Cosmology in a supersymmetric model with gauged B  L symmetry
SARKAR, A; YAJNIK, UA (AMER PHYSICAL SOC, 2007)We consider salient cosmological features of a supersymmetric model which is leftright symmetric and therefore possessing gauged BL symmetry. The requirement of breaking parity and also obtaining charge preserving vacua ... 
Dark matter and leptogenesis in gauged BL symmetric models embedding vMSM
SAHU, N; YAJNIK, UA (ELSEVIER SCIENCE BV, 2006)We study the phenomenon of baryogenesis via leptogenesis in the gauged BL symmetric models by embedding the currently proposed model nu MSM. It is shown that the lightest righthanded neutrino of mass 100 GeV satisfy the ... 
Discussion on a possible neutrino detector located in india
MURTHY, MVN; YAJNIK, UA; BALAJI, KRS; BHATTACHARYYA, G; DIGHE, A; DUGAD, S; DASS, NDH; KABIR, PK; KAR, K; INDUMATHI, D; LEARNED, JG; MAJUMDAR, D; MONDAL, NK; NAYAK, SN; PAKVASA, S; RAYCHAUDHURI, A; RAGHAVAN, RS; RAJASEKARAN, G; RAMACHANDRAN, R; RAY, AK; RINDANI, S; SHARATCHANDRA, HS; SINHA, R; SINHA, N; UMASANKAR, S (INDIAN ACADEMY SCIENCES, 2000)We have identified some important and worthwhile physics opportunities with a possible neutrino detector located in India. Particular emphasis is placed on the geographical advantage with a stress on the complimentary ... 
Fate of the false monopoles: Induced vacuum decay
KUMAR, B; PARANJAPE, MB; YAJNIK, UA (AMER PHYSICAL SOC, 2010)We study a gauge theory model where there is an intermediate symmetry breaking to a metastable vacuum that breaks a simple gauge group to a U(1) factor. Such a model admits the existence of metastable magnetic monopoles, ... 
Flowering to bloom of PeV scale supersymmetric leftright symmetric models
YAJNIK, UA; SARKAR, A; MISHRA, S; BORAH, D (INDIAN ACAD SCIENCES, 2016)Unified models incorporating righthanded neutrino in a symmetric way generically possess parity symmetry. If this is broken spontaneously, it results in the formation of domain walls in the early Universe, whose persistence ... 
Gauge mediated supersymmetry breaking and the cosmology of the leftright symmetric model
MISHRA, S; YAJNIK, UA; SARKAR, A (AMER PHYSICAL SOC, 2009)Leftright symmetry including supersymmetry presents an important class of gauge models which may possess natural solutions to many issues of phenomenology. Cosmology of such models indicates a phase transition accompanied ... 
Gauged BL symmetry and baryogenesis via leptogenesis at TeV scale
SAHU, N; YAJNIK, UA (AMERICAN PHYSICAL SOC, 2005)It is shown that the requirement of preservation of baryon asymmetry does not rule out a scale for leptogenesis as low as 10 TeV. The conclusions are compatible with seesaw mechanism if, for example, the pivot mass scale ... 
Gauged BL unification and cosmology
YAJNIK, UA (AMER INST PHYSICS, 2007)We discuss some cosmological implications of low energy gauged BL symmetry with and without supersymmetry. Generic possibility of leptogenesis from a domain wall driven first order phase transition is shown to be a ... 
Graceful exit via monopoles in a theory with O'Raifeartaigh type supersymmetry breaking
KUMAR, B; YAJNIK, UA (ELSEVIER SCIENCE BV, 2010)We study the stability of supersymmetry breaking metastable vacua and supersymmetric vacua in the presence of solitons. The metastable vacua of supersymmetric QCD and those found elsewhere such as in models based on the ... 
Inflation with bulk fields in the RandallSundrum warped compactification?
CLINE, J; YAJNIK, UA (INDIAN ACADEMY SCIENCES, 2000) 
Infrared Abelian dominance without Abelian projection
RAVAL, H; YAJNIK, UA (AMER PHYSICAL SOC, 2015)Maximal Abelian gauge has been a particular choice to study dynamical generation of offdiagonal gluon masses in QCD. This gauge is a special case of an Abelian projection. Abelian dominance is characterized by offdiagonal ...