1,738 research outputs found

    Toward solving the cosmological constant problem by embedding

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    The typical scalar field theory has a cosmological constant problem. We propose a generic mechanism by which this problem is avoided at tree level by embedding the theory into a larger theory. The metric and the scalar field coupling constants in the original theory do not need to be fine-tuned, while the extra scalar field parameters and the metric associated with the extended theory are fine-tuned dynamically. Hence, no fine-tuning of parameters in the full Lagrangian is needed for the vacuum energy in the new physical system to vanish at tree level. The cosmological constant problem can be solved if the method can be extended to quantum loops.Comment: published versio

    A Classification and Analysis of Higgs-flavor Models

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    A classification is given of Higgs-flavor models. In these models, there are several Higgs doublets in an irreducible multiplet R_{Phi} of a non-abelian symmetry G_{Phi}, under which the quarks and leptons do not transform (thus giving minimal flavor-changing for the fermions). It is found that different G_{Phi} and R_{Phi} lead to very distinctive spectra of the extra Higgs doublets, including different numbers of "sequential Higgs" and of "inert Higgs" that could play the role of dark matter, different mass relations, and different patterns of SU(2)_L-breaking splittings within the Higgs doublets.Comment: 35 page

    Constraints on Deflation from the Equation of State of Dark Energy

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    In cyclic cosmology based on phantom dark energy the requirement that our universe satisfy a CBE-condition ({\it Comes Back Empty}) imposes a lower bound on the number NcpN_{\rm cp} of causal patches which separate just prior to turnaround. This bound depends on the dark energy equation of state w=p/ρ=1ϕw = p/\rho = -1 - \phi with ϕ>0\phi > 0. More accurate measurement of ϕ\phi will constrain NcpN_{\rm cp}. The critical density ρc\rho_c in the model has a lower bound ρc(109GeV)4\rho_c \ge (10^9 {\rm GeV})^4 or ρc(1018GeV)4\rho_c \ge (10^{18} {\rm GeV})^4 when the smallest bound state has size 101510^{-15}m, or 103510^{-35}m, respectively.Comment: 23 pages, 3 figures, typos fixe

    Mersenne Primes, Polygonal Anomalies and String Theory Classification

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    It is pointed out that the Mersenne primes Mp=(2p1)M_p=(2^p-1) and associated perfect numbers Mp=2p1Mp{\cal M}_p=2^{p-1}M_p play a significant role in string theory; this observation may suggest a classification of consistent string theories.Comment: 10 pages LaTe

    Wormhole Cosmology and the Horizon Problem

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    We construct an explicit class of dynamic lorentzian wormholes connecting Friedmann-Robertson-Walker (FRW) spacetimes. These wormholes can allow two-way transmission of signals between spatially separated regions of spacetime and could permit such regions to come into thermal contact. The cosmology of a network of early Universe wormholes is discussed.Comment: 13 pages, in RevTe

    On Resilient Behaviors in Computational Systems and Environments

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    The present article introduces a reference framework for discussing resilience of computational systems. Rather than a property that may or may not be exhibited by a system, resilience is interpreted here as the emerging result of a dynamic process. Said process represents the dynamic interplay between the behaviors exercised by a system and those of the environment it is set to operate in. As a result of this interpretation, coherent definitions of several aspects of resilience can be derived and proposed, including elasticity, change tolerance, and antifragility. Definitions are also provided for measures of the risk of unresilience as well as for the optimal match of a given resilient design with respect to the current environmental conditions. Finally, a resilience strategy based on our model is exemplified through a simple scenario.Comment: The final publication is available at Springer via http://dx.doi.org/10.1007/s40860-015-0002-6 The paper considerably extends the results of two conference papers that are available at http://ow.ly/KWfkj and http://ow.ly/KWfgO. Text and formalism in those papers has been used or adapted in the herewith submitted pape
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