Production of Black Holes in TeV-Scale Gravity

Copious production of microscopic black holes is one of the least model-dependent predictions of TeV-scale gravity scenarios. We review the arguments behind this assertion and discuss opportunities to track the striking associated signatures in the near future. These include searches at neutrino telescopes, such as AMANDA and RICE, at cosmic ray air shower facilities, such as the Pierre Auger Observatory, and at colliders, such as the Large Hadron Collider.Comment: 8 pages, 10 figures, fortschritte.sty (included); talk presented at the 35th International Symposium Ahrenshoop on the Theory of Elementary Particles, Aug. 26-30, 2002, Berlin-Schmoeckwitz, German

On the emergence of scale-free production networks

We propose a simple dynamical model of the formation of production networks among monopolistically competitive firms. The model subsumes the standard general equilibrium approach \`a la Arrow-Debreu but displays a wide set of potential dynamic behaviors. It robustly reproduces key stylized facts of firms' demographics. Our main result is that competition between intermediate good producers generically leads to the emergence of scale-free production networks.Comment: 31 pages, 15 figure

Innovation Complementarity and Scale of Production

complementarity; supermodularity; non-observed heterogeneity; product innovation; process innovation

Microscopic Black Hole Production in TeV-Scale Gravity

Models with extra spatial dimensions and TeV-scale gravity offer the first opportunity to test the conjecture of black hole formation in trans-Planckian energy scattering with small impact parameters. After a brief review of gravitational scattering at ultrahigh energies and scenarios of TeV-scale gravity, search strategies at the LHC, at the Pierre Auger (cosmic ray) Observatory and at the neutrino telescopes AMANDA/IceCube are illustrated with the simplest but nevertheless representative example: production of Schwarzschild black holes and their observation via Hawking radiation in the large extra dimension scenario. Some more general features of the production of higher-dimensional black holes and/or uncertainties in the estimates are also outlined.Comment: 18 pages, 5 figures; Talk presented at XXX ITEP Winter School of Physics, Moscow, Russia, February 2002, references adde

Large-scale structure of a nation-wide production network

Production in an economy is a set of firms' activities as suppliers and customers; a firm buys goods from other firms, puts value added and sells products to others in a giant network of production. Empirical study is lacking despite the fact that the structure of the production network is important to understand and make models for many aspects of dynamics in economy. We study a nation-wide production network comprising a million firms and millions of supplier-customer links by using recent statistical methods developed in physics. We show in the empirical analysis scale-free degree distribution, disassortativity, correlation of degree to firm-size, and community structure having sectoral and regional modules. Since suppliers usually provide credit to their customers, who supply it to theirs in turn, each link is actually a creditor-debtor relationship. We also study chains of failures or bankruptcies that take place along those links in the network, and corresponding avalanche-size distribution.Comment: 17 pages with 8 figures; revised section VI and references adde

GeV-scale dark matter: production at the Main Injector

Assuming that dark matter particles interact with quarks via a GeV-scale mediator, we study dark matter production in fixed target collisions. The ensuing signal in a neutrino near detector consists of neutral-current events with an energy distribution peaked at higher values than the neutrino background. We find that for a $Z'$ boson of mass around a few GeV that decays to dark matter particles, the dark matter beam produced by the Main Injector at Fermilab allows the exploration of a range of values for the gauge coupling that currently satisfy all experimental constraints. The NO$\nu$A detector is well positioned for probing the presence of a dark matter beam, while future LBNF near-detectors would provide more sensitive probes.Comment: 25 pages, 9 figure