scholarly journals Tachyonic inflation on (non-)Archimedean spaces

2016 ◽  
Vol 14 (3) ◽  
pp. 257-274
Author(s):  
Milan Milosevic ◽  
Goran Djordjevic

The relevance of quantum rolling tachyons and corresponding inflation scenario in the frame of the standard, p-adic and adelic cosmology are reviewed. The field theory of tachyon matter proposed by Sen in a zero-dimensional version leads to a number of models with a particle moving under different potentials. We consider quantum propagators of the models, as well as, the vacuum states and conditions necessary to construct an adelic generalization. In addition we present inflationary scenarios for some interesting models based on analytic and numeric calculations. A brief overview of the state of art in the field and suggestions for further consideration close the paper.

2020 ◽  
Vol 2020 (1) ◽  
pp. 105-108
Author(s):  
Ali Alsam

Vision is the science that informs us about the biological and evolutionary algorithms that our eyes, opticnerves and brains have chosen over time to see. This article is an attempt to solve the problem of colour to grey conversion, by borrowing ideas from vision science. We introduce an algorithm that measures contrast along the opponent colour directions and use the results to combine a three dimensional colour space into a grey. The results indicate that the proposed algorithm competes with the state of art algorithms.


2019 ◽  
Vol 21 (4) ◽  
pp. 458-465
Author(s):  
A.I. Sushkov ◽  
◽  
T.A. Astrelina ◽  
E.V. Shestero ◽  
V.A. Nikitina ◽  
...  

2021 ◽  
Author(s):  
Xi Zhang ◽  
Yaping Zhang ◽  
xijun wei ◽  
Chaohui Wei ◽  
Yingze Song

Li–S batteries (LBSs) have received extensive attention owing to their remarkable theoretical capacity (1672 mA h g–1) and high energy density (2600 Wh kg–1), far beyond the state of art...


2019 ◽  
Vol 48 (21) ◽  
pp. 7122-7129 ◽  
Author(s):  
Chia-Jui Chang ◽  
You-Chiuan Chu ◽  
Hao-Yu Yan ◽  
Yen-Fa Liao ◽  
Hao Ming Chen

The state-of-art RuO2 catalyst for the oxygen evolution reaction (OER) is measured by using in situ X-ray absorption spectroscopy (XAS) to elucidate the structural transformation during catalyzing the reaction in acidic and alkaline conditions.


Arts ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 28
Author(s):  
Katy Deepwell

This essay is in four parts. The first offers a critique of James Elkins and Michael Newman’s book The State of Art Criticism (Routledge, 2008) for what it tells us about art criticism in academia and journalism and feminism; the second considers how a gendered analysis measures the “state” of art and art criticism as a feminist intervention; and the third, how neo-liberal mis-readings of Linda Nochlin and Laura Mulvey in the art world represent feminism in ideas about “greatness” and the “gaze”, whilst avoiding feminist arguments about women artists or their work, particularly on “motherhood”. In the fourth part, against the limits of the first three, the state of feminist art criticism across the last fifty years is reconsidered by highlighting the plurality of feminisms in transnational, transgenerational and progressive alliances.


2019 ◽  
Vol 28 (14) ◽  
pp. 1944006
Author(s):  
ChunJun Cao ◽  
Aidan Chatwin-Davies ◽  
Ashmeet Singh

According to the holographic bound, there is only a finite density of degrees of freedom in space when gravity is taken into account. Conventional quantum field theory does not conform to this bound, since in this framework, infinitely many degrees of freedom may be localized to any given region of space. In this paper, we explore the viewpoint that quantum field theory may emerge from an underlying theory that is locally finite-dimensional, and we construct a locally finite-dimensional version of a Klein–Gordon scalar field using generalized Clifford algebras. Demanding that the finite-dimensional field operators obey a suitable version of the canonical commutation relations makes this construction essentially unique. We then find that enforcing local finite dimensionality in a holographically consistent way leads to a huge suppression of the quantum contribution to vacuum energy, to the point that the theoretical prediction becomes plausibly consistent with observations.


2012 ◽  
Vol 23 (09) ◽  
pp. 1250094 ◽  
Author(s):  
VLADIMIR TURAEV ◽  
ALEXIS VIRELIZIER

Given a discrete group G and a spherical G-fusion category whose neutral component has invertible dimension, we use the state-sum method to construct a 3-dimensional Homotopy Quantum Field Theory with target the Eilenberg–MacLane space K(G, 1).


2016 ◽  
Vol 25 (04) ◽  
pp. 1630010 ◽  
Author(s):  
Salvatore Capozziello ◽  
Orlando Luongo ◽  
Mariacristina Paolella

Several models of [Formula: see text] gravity have been proposed in order to address the dark side problem in cosmology. However, these models should be constrained also at ultraviolet scales in order to achieve some correct fundamental interpretation. Here, we analyze this possibility comparing quantum vacuum states in given [Formula: see text] cosmological backgrounds. Specifically, we compare the Bogolubov transformations associated to different vacuum states for some [Formula: see text] models. The procedure consists in fixing the [Formula: see text] free parameters by requiring that the Bogolubov coefficients can be correspondingly minimized to be in agreement with both high redshift observations and quantum field theory predictions. In such a way, the particle production is related to the value of the Hubble parameter and then to the given [Formula: see text] model. The approach is developed in both metric and Palatini formalism.


2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Daniela Ligi ◽  
Lidia Croce ◽  
Ferdinando Mannello
Keyword(s):  

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