Now showing items 1-20 of 35

    • B-L cosmic strings and baryogenesis 

      BHATTACHARJEE, P; SAHU, N; YAJNIK, UA (AMERICAN PHYSICAL SOC, 2004)
      Cosmic strings arising from breaking of the U(1)(B-L) gauge symmetry that occurs in a wide variety of unified models can carry zero modes of heavy Majorana neutrinos. Decaying and/or repeatedly self-interacting 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 B-L cosmic strings of a U(1)(B-L) extension of the Standard Model. The disappearance of closed loops of B-L cosmic strings can produce heavy right handed neutrinos, N-R'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 + 1-dimensional generalization of the 2 + 1-dimensional 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 two-Higgs-doublet 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 two-Higgs-doublet 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 PHASE-TRANSITION 

      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 phase-transition - 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 left-right symmetric and therefore possessing gauged B-L symmetry. The requirement of breaking parity and also obtaining charge preserving vacua ...
    • Dark matter and leptogenesis in gauged B-L symmetric models embedding vMSM 

      SAHU, N; YAJNIK, UA (ELSEVIER SCIENCE BV, 2006)
      We study the phenomenon of baryogenesis via leptogenesis in the gauged B-L symmetric models by embedding the currently proposed model nu MSM. It is shown that the lightest right-handed 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, ...
    • Gauge mediated supersymmetry breaking and the cosmology of the left-right symmetric model 

      MISHRA, S; YAJNIK, UA; SARKAR, A (AMER PHYSICAL SOC, 2009)
      Left-right 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 B-L 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 see-saw mechanism if, for example, the pivot mass scale ...
    • Gauged B-L unification and cosmology 

      YAJNIK, UA (AMER INST PHYSICS, 2007)
      We discuss some cosmological implications of low energy gauged B-L 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 Randall-Sundrum 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 off-diagonal gluon masses in QCD. This gauge is a special case of an Abelian projection. Abelian dominance is characterized by off-diagonal ...
    • Leptogenesis with left-right domain walls 

      YAJNIK, UA; CLINE, J; RABIKUMAR, M (INDIAN ACADEMY SCIENCES, 2004)
      The presence of domain walls separating regions of unbroken SU(2)(L) and SU(2)(R) is shown to provide necessary conditions for leptogenesis which converts later to the observed baryon asymmetry., The strength of lepton ...