Endogenous Growth and Human Capital: A Comparative Study of Pakistan and Sri Lanka

Economic Growth has posed an intellectual challenge ever since the beginning of systematic economic analysis. Adam Smith claimed that growth was related to division of labour, but he did not link them in a clear way. After that Thomas Malthus developed a formal model of a dynamic economic growth process in which each country converge toward stationary per-capita income. According to this model, death rates fall and fertility rises when income exceed the equilibrium, and opposite occur when incomes are less than that level. Despite the influence of the Malthusian model in nineteenth century economists, fertility fell rather than rose as income grew during the past 150 years in the west and other parts of the world. The Neoclassical growth model of Solow (1956), which has been for the past thirty years the central framework to account for economic growth, focuses on exogenous technical population factors that determine output-input ratios, responded to the failure of Malthusian model. Neither Malthus’s nor the Neoclassicists approach to growth pays much attention to Human Capital. Yet the evidence is quite strong of close link between investments in human capital and economic growth. Since human capital embodied knowledge and skills, and economic development depends on advances in technological and scientific knowledge, development presumably depends on the accumulation of human capital. Investment in human capital has been a major source of economic growth in advanced countries. The negligible amount of human investments in underdeveloped countries has done a little to extend the capacity of people to meet the challenge of accelerated development.

Anomalous U(1): Solving Various Puzzles Of MSSM And SU(5) GUT

We discuss how an anomalous U(1) symmetry when appended to MSSM and SUSY GUTs [e.g. SU(5)] can help overcome a variety of puzzles related to charged fermion masses and mixings, flavor changing processes, proton decay and neutrino oscillations. Proton lifetime for SU(5) GUT, in particular, is predicted in a range accessible to the ongoing or planned searches.Comment: Presented at NOON2001 Workshop, Kashiwa, Japan, 5-8 Dec. 200

From Hybrid to Quadratic Inflation With High-Scale Supersymmetry Breaking

Motivated by the reported discovery of inflationary gravity waves by the BICEP2 experiment, we propose an inflationary scenario in supergravity, based on the standard superpotential used in hybrid inflation. The new model yields a tensor-to-scalar ratio r ~ 0.14 and scalar spectral index ns ~ 0.964, corresponding to quadratic (chaotic) inflation. The important new ingredients are the high-scale, (1.6-10) x 10^13 GeV, soft supersymmetry breaking mass for the gauge singlet inflaton field and a shift symmetry imposed on the K\"ahler potential. The end of inflation is accompanied, as in the earlier hybrid inflation models, by the breaking of a gauge symmetry at (1.2-7.1) x 10^16 GeV, comparable to the grand-unification scale.Comment: Version with minor corrections to appear in PL

Gravity Waves and Gravitino Dark Matter in μ\mu-Hybrid Inflation

We propose a novel reformulation of supersymmetric (more precisely $\mu$-) hybrid inflation based on a local U(1) or any suitable extension of the minimal supersymmetric standard model (MSSM) which also resolves the $\mu$ problem. We employ a suitable Kahler potential which effectively yields quartic inflation with non-minimal coupling to gravity. Imposing the gravitino Big Bang Nucleosynthesis (BBN) constraint on the reheat temperature ($T_r \lesssim 10^6$ GeV) and requiring a neutralino LSP, the tensor to scalar ratio ($r$) has a lower bound $r \gtrsim 0.004$. The U(1) symmetry breaking scale lies between $10^8$ and $10^{12}$ GeV. We also discuss a scenario with gravitino dark matter whose mass is a few GeV.Comment: 5 pages, 4 figures, revised version to appear in Physics Letters

The Role of Human Capital in Economic Growth: A Comparative Study of Pakistan and India

Economic Growth has posed an intellectual challenge ever since the beginning of systematic economic analysis. Adam Smith claimed that growth was related to division of labour, but he did not link them in a clear way. After that Thomas Malthus developed a formal model of a dynamic economic growth process in which each country converge toward stationary per capita income. According to this model, death rates fall and fertility rises when income exceed the equilibrium, and opposite occur when incomes are less than that level. Despite the influence of the Malthusian model in nineteenth century economists, fertility feel rather than rose as income grew during the past 150 years in the west and other parts of the world. The Neoclassical growth model of Solow (1956), which has been for the past thirty years the central framework to account for economic growth, focuses on exogenous technical population factors that determine output-input ratios, responded to the failure of Malthusian model. Neither Malthus’s nor the Neoclassicists approach to growth pays much attention to Human Capital. Yet the evidence is quite strong of close link between investments in human capital and economic growth. Since human capital embodied knowledge and skills, and economic development depends on advances in technological and scientific knowledge, development presumably depends on the accumulation of human capital. Investment in human capital has been a major source of economic growth in advanced countries.

Higgs Inflation, Seesaw Physics and Fermion Dark Matter

We present an inflationary model in which the Standard Model Higgs doublet field with non-minimal coupling to gravity drives inflation, and the effective Higgs potential is stabilized by new physics which includes a dark matter particle and right-handed neutrinos for the seesaw mechanism. All of the new particles are fermions, so that the Higgs doublet is the unique inflaton candidate. With central values for the masses of the top quark and the Higgs boson, the renormalization group improved Higgs potential is employed to yield the scalar spectral index $n_s \simeq 0.968$, the tensor-to-scalar ratio $r \simeq 0.003$, and the running of the spectral index $\alpha=dn_s/d \ln k \simeq -5.2 \times 10^{-4}$ for the number of e-folds $N_0=60$ ($n_s \simeq 0.962$, $r \simeq 0.004$, and $\alpha \simeq -7.5 \times 10^{-4}$ for $N_0=50$). The fairly low value of $r \simeq 0.003$ predicted in this class of models means that the ongoing space and land based experiments are not expected to observe gravity waves generated during inflation. [Dedicated to the memory of Dr. Paul Weber (1947 - 2015). Paul was an exceptional human being and a very special friend who will be sorely missed.]Comment: 15 pages, 3 figure

\theta_13, Rare Processes and Proton Decay in Flipped SU(5)

We consider an extended flipped SU(5) model, supplemented by a flavor ${\cal U}(1)$ symmetry, which yields bi-large neutrino mixings, charged fermion mass hierarchies and CKM mixings. The third leptonic mixing angle \te_{13} turns out to lie close to 0.07, and neutrino CP violation can be estimated from the observed baryon asymmetry. For lepton flavor violating processes we find the branching ratios, {\rm BR}(\mu \to e\ga)\sim {\rm BR}(\tau \to e \ga) \sim 10^{-4}\cdot {\rm BR}(\tau \to \mu \ga) \stackrel{<}{_\sim}5\cdot 10^{-14}. The proton lifetime $\tau_{p\to \pi^0 e^{+}}\simeq 10^{34}-10^{36}$ yrs.Comment: Discussion on leptogenesis and CP violation, and references adde

Induced-Gravity GUT-Scale Higgs Inflation in Supergravity

Models of induced-gravity inflation are formulated within Supergravity employing as inflaton the Higgs field which leads to a spontaneous breaking of a U(1)B-L symmetry at Mgut=2x10^16 GeV. We use a renormalizable superpotential, fixed by a U(1) R symmetry, and Kahler potentials which exhibit a quadratic non-minimal coupling to gravity with or without an independent kinetic mixing in the inflaton sector. In both cases we find inflationary solutions of Starobinsky type whereas in the latter case, others (more marginal) which resemble those of linear inflation arise too. In all cases the inflaton mass is predicted to be of the order of 10^13~GeV. Extending the superpotential of the model with suitable terms, we show how the MSSM mu parameter can be generated. Also, non-thermal leptogenesis can be successfully realized, provided that the gravitino is heavier than about 10 TeV.Comment: arXiv admin note: text overlap with arXiv:1710.05759; Final versio