Plateau Inflation from Random Non-Minimal Coupling

A generic non-minimal coupling can push any higher-order terms of the scalar potential sufficiently far out in field space to yield observationally viable plateau inflation. We provide analytic and numerical evidence that this generically happens for a non-minimal coupling strength $\xi$ of the order $N_e^2$. In this regime, the non-minimally coupled field is sub-Planckian during inflation and is thus protected from most higher-order terms. For larger values of $\xi$, the inflationary predictions converge towards the sweet spot of PLANCK. The latter includes $\xi\simeq 10^4$ obtained from CMB normalization arguments, thus providing a natural explanation for the inflationary observables measured.Comment: 9 pages, twocolumn, some figures; v2: 1 figure and appendix added, jcap layou

On the Herbrand-Kleene universe for nondeterministic computations

AbstractFor nondeterministic recursive equations over an arbitrary signature of function symbols including the nondeterministic choice operator “or” the interpretation is factorized according to the techniques developed by the present author (1982). It is shown that one can either associate an infinite tree with the equations, then interpret the function symbol “or” as a nondeterministic choice operator and so mapping the tree onto a set of infinite trees and then interpret these trees. Or one can interpret the recursive equation directly yielding a set-valued function. Both possibilities lead to the same result, i.e., one obtains a commuting diagram. However, one has to use more refined techniques than just powerdomains. This explains and solves a problem posed by Nivat (1980). Basically, the construction gives a generalization of the powerdomain approach applicable to arbitrary nonflat (nondiscrete) algebraic domains

Pole Inflation - Shift Symmetry and Universal Corrections

An appealing explanation for the Planck data is provided by inflationary models with a singular non-canonical kinetic term: a Laurent expansion of the kinetic function translates into a potential with a nearly shift-symmetric plateau in canonical fields. The shift symmetry can be broken at large field values by including higher-order poles, which need to be hierarchically suppressed in order not to spoil the inflationary plateau. The herefrom resulting corrections to the inflationary dynamics and predictions are shown to be universal at lowest order and possibly to induce power loss at large angular scales. At lowest order there are no corrections from a pole of just one order higher and we argue that this phenomenon is related to the well-known extended no-scale structure arising in string theory scenarios. Finally, we outline which other corrections may arise from string loop effects.Comment: twocolumn, 9 pages, 1 figure; v2: clarifications and refs added, JHEP layout, 19 page

Detecting Media Bias

The program is intended to help students develop media literacy; it allows them to understand the news’s biases in everyday life

Starobinsky-Type Inflation from α′\alpha'-Corrections

Working in the Large Volume Scenario (LVS) of IIB Calabi-Yau flux compactifications, we construct inflationary models from recently computed higher derivative $(\alpha')^3$-corrections. Inflation is driven by a Kaehler modulus whose potential arises from the aforementioned corrections, while we use the inclusion of string loop effects just to ensure the existence of a graceful exit when necessary. The effective inflaton potential takes a Starobinsky-type form $V=V_0(1-e^{-\nu\phi})^2$, where we obtain one set-up with $\nu=-1/\sqrt{3}$ and one with $\nu=2/\sqrt{3}$ corresponding to inflation occurring for increasing or decreasing $\phi$ respectively. The inflationary observables are thus in perfect agreement with PLANCK, while the two scenarios remain observationally distinguishable via slightly varying predictions for the tensor-to-scalar ratio $r$. Both set-ups yield $r\simeq (2\ldots 7)\,\times 10^{-3}$. They hence realise inflation with moderately large fields $\left(\Delta\phi\sim 6\thinspace M_{Pl}\right)$ without saturating the Lyth bound. Control over higher corrections relies in part on tuning underlying microscopic parameters, and in part on intrinsic suppressions. The intrinsic part of control arises as a leftover from an approximate effective shift symmetry at parametrically large volume.Comment: 29 pages, 6 figures; v2: clarifications and refs adde

Nodes and Hubs: An Exploration of Yiguandao Temples as ‘Portals of Globalization’

This paper takes a fresh look at the global spread of the Chinese–Taiwanese new religious movement Yiguandao (一貫道; the emic transcription is “I-Kuan Tao”) by directing attention to the concrete places where transnational connections and interactions actually transpire, i.e., temples, shrines, and other sites of worship. Emically known as “Buddha halls” (fotang 佛堂), these places range from large-scale temple complexes, to small niches of worship in people’s private residences. Yet, they all share the potential of becoming venues of transregional interactions through processes of migration, the circulation of personnel, and local outreach. I argued that we need to take the distinct character of these localities more seriously, in order to fully understand the global networks of Yiguandao groups. Through their specific embeddedness in both local affairs and transnational projects, these temples are not simply local chapters of the (mostly) Taiwanese headquarters, but instead they are “translocalities” or even “portals of globalization”—two concepts developed in migration and global studies to help understand the significance of place in the recent phase of so-called globalization. By exploring Yiguandao temples across the globe, this paper critically evaluated these approaches, and their usefulness for the study of global religions. Empirically, it drew on both print and online material, as well as ethnographic fieldwork conducted by the author in Taiwan, Vienna (Austria), California, South Africa, and Japan from 2016 to 2018