Synthesis and Properties of High Tilted Antiferroelectric Esters with Partially Fluorinated Alkoxyalkoxy Terminal Chains

Novel chiral esters with partially fluorinated alkoxyalkoxy terminal chains are described. Their phase transition temperatures, enthalpies, and electrooptical properties are reported. A helical pitch in pure compounds and their mixtures based on selective reflection of light is also characterized

Quantum phantom cosmology

We apply the formalism of quantum cosmology to models containing a phantom field. Three models are discussed explicitly: a toy model, a model with an exponential phantom potential, and a model with phantom field accompanied by a negative cosmological constant. In all these cases we calculate the classical trajectories in configuration space and give solutions to the Wheeler-DeWitt equation in quantum cosmology. In the cases of the toy model and the model with exponential potential we are able to solve the Wheeler-DeWitt equation exactly. For comparison, we also give the corresponding solutions for an ordinary scalar field. We discuss in particular the behaviour of wave packets in minisuperspace. For the phantom field these packets disperse in the region that corresponds to the Big Rip singularity. This thus constitutes a genuine quantum region at large scales, described by a regular solution of the Wheeler-DeWitt equation. For the ordinary scalar field, the Big-Bang singularity is avoided. Some remarks on the arrow of time in phantom models as well as on the relation of phantom models to loop quantum cosmology are given.Comment: 21 pages, 6 figure

Ab-initio calculations of the optical properties of the Si(113)3x2ADI surface

We investigated the stable silicon (113) surface with a 3x2ADI reconstruction by ab-initio methods. The ground state properties have been obtained using the density-functional theory. We present the dispersion of the electronic band structure, where the surface bands have been distinguished from the projected bulk bands by calculating their localization in the slab. The optical spectra, here the reflectance anisotropy (RAS), have been obtained within the independent particle random phase approximation. We identified surface features in the spectra tracing them back to the responsible electronic states and, studied their localization in the slab. A comparison with available experimental data for the band structure and the RAS shows a good agreement.Comment: 10 pages, 10 figure

Regularizing cosmological singularities by varying physical constants

Varying physical constant cosmologies were claimed to solve standard cosmological problems such as the horizon, the flatness and the $\Lambda$-problem. In this paper, we suggest yet another possible application of these theories: solving the singularity problem. By specifying some examples we show that various cosmological singularities may be regularized provided the physical constants evolve in time in an appropriate way.Comment: 9 pages, 6 figures, Revtex4-1, an improved version to appear in JCA

Boson Stars as Gravitational Lenses

We discuss boson stars as possible gravitational lenses and study the lensing effect by these objects made of scalar particles. The mass and the size of a boson star may vary from an individual Newtonian object similar to the Sun to the general relativistic size and mass of a galaxy close to its Schwarzschild radius. We assume boson stars to be transparent which allows the light to pass through them though the light is gravitationally deflected. We assume boson stars of the mass $M = 10^{10}M_\odot$ to be on non-cosmological distance from the observer. We discuss the lens equation for these stars as well as the details of magnification. We find that there are typically three images of a star but the deflection angles may vary from arcseconds to even degrees. There is one tangential critical curve (Einstein ring) and one radial critical curve for tangential and radial magnification, respectively. Moreover, the deflection angles for the light passing in the gravitational field of boson stars can be very large (even of the order of degrees) which reflects the fact they are very strong relativistic objects. We also propose a suitable formula for the lens equation for such large deflection angles, and with the reservation that large deflection angle images are highly demagnified but in the area of the tangential critical curve, their existence may help in observational detection of suitable lenses possessing characteristic features of boson stars which could also serve as a direct evidence for scalar fields in the universe.Comment: accepted by Astrophys. J., 31 pages, AASTeX, 6 figure

Finitely-Generated Projective Modules over the Theta-deformed 4-sphere

We investigate the "theta-deformed spheres" C(S^{3}_{theta}) and C(S^{4}_{theta}), where theta is any real number. We show that all finitely-generated projective modules over C(S^{3}_{theta}) are free, and that C(S^{4}_{theta}) has the cancellation property. We classify and construct all finitely-generated projective modules over C(S^{4}_{\theta}) up to isomorphism. An interesting feature is that if theta is irrational then there are nontrivial "rank-1" modules over C(S^{4}_{\theta}). In that case, every finitely-generated projective module over C(S^{4}_{\theta}) is a sum of a rank-1 module and a free module. If theta is rational, the situation mirrors that for the commutative case theta=0.Comment: 34 page

Controversial experience tourism in the eyes of generation Y representatives

This paper was written to contribute to the discussion on the perspectives of the development of selected forms of controversial tourism by means of: 1) surveying opinions of Generation Y representatives on how familiar they are with individual forms; 2) determining the responders’ impressions on acceptance of these forms; 3) gathering opinions on the perspectives of development of these forms. The starting point for the discussion is to approach the motives for such travels from the perspective of the concept of experience economy and to limit the research to tourism forms developing in response to the need of novelty, sensations and experiences. The demand factor connected with the need to maximize sensations shaped a specific form of tourism, described in this study as controversial experience tourism. It comprises sex tourism, drug tourism, disaster tourism, extreme tourism, thanatourism, esoteric tourism, urban exploring and poorism. The study was carried out with the help of the CAWI technique between February and May 2018 and involved 407 participants aged 18–26. The obtained results suggest relatively low future interest in forms of tourism that are perceived as strongly controversial. The thirst for new experiences and sensations is fully satisfied by these forms of extreme tourism that are positively perceived and do not arouse ethical controversies.Celem pracy jest włączenie się w dyskusję nad perspektywami rozwoju wybranych form turystyki kontrowersyjnej poprzez: 1) zbadanie opinii przedstawicieli pokolenia Y na temat oceny stopnia znajomości poszczególnych form, 2) określenie odczuć respondentów na temat ich akceptacji, 3) zebranie opinii na temat perspektyw rozwojowych wskazanych form. Punktem wyjścia do dyskusji jest spojrzenie na motywy podejmowanych podróży z perspektywy koncepcji tzw. ekonomii doświadczeń oraz ograniczenie zakresu problemowego do form turystyki rozwijających się pod wpływem potrzeby poszukiwania nowości, wrażeń, doświadczeń. Czynnik popytu związany z potrzebą maksymalizacji wrażeń ukształtował pewną specyficzną grupę form turystyki, określoną na potrzeby analizy jako kontrowersyjna turystyka wrażeń. W jej zakres włączono: turystykę seksualną, narkoturystykę, turystykę katastrof, ekstremalną, tanatoturystykę, turystykę ezoteryczną, urban exploring i poorism. Badanie wykonano z zastosowaniem techniki CAWI, w okresie od lutego do maja 2018 roku z udziałem 407 respondentów w przedziale wiekowym 18–26 lat. Uzyskane wyniki sugerują stosunkowo niewielkie zainteresowanie w przyszłości formami turystyki, które kojarzone są jako silnie kontrowersyjne. Potrzebę zdobywania nowych doświadczeń i wrażeń w pełni zapewniają formy turystyki ekstremalnej, które postrzegane są pozytywnie i nie wywołują kontrowersji natury etycznej

When dreams come true – urban land use and management trends desired by residents and participatory budgeting – a case study in Toruń

Social participation allows public authorities to learn about communities’ views and thus to jointly work out satisfying solutions. The pre-1989 law in Poland generally prevented the possibility of citizens taking part in the making of decisions about the use of public areas. Over the following years participatory decision-making was adopted, which evolved and expanded as new tools were introduced which encourage citizen involvement. The municipality of Toruń adopted a participatory approach to budgeting in 2014 so that the city’s residents could influence the use of public land in their neighbourhoods according to their needs. The total amount of funding spent on participatory budgets between 2014 and 2017 exceeded PLN 26 million. The aim of the study is to prepare a typology of desired changes in the city of Toruń and to identify the level of social participation on the basis of projects nominated for financing from the participatory budget. To this end, the types of projects and the turnout of the residents who voted were analysed by place of residence. The study showed that both the number of nominated projects and the number of voters increased in the years covered by the survey, thus pointing to the success of participatory budgeting, a form of schooling in local democracy, in Toruń

Idea miast partnerskich a jej znaczenie dla rozwoju współczesnych miast – perspektywa geograficzna. Przykład Leszna

Idea miast partnerskich w obecnym kształcie jest pokłosiem procesów rozpoczętych po zakończeniu II wojny światowej. Nowa rzeczywistość powojenna skłania bowiem kolejne samorządy miejskie do nawiązywania wzajemnych kontaktów w celu wspólnego zapobiegania dalszym konfliktom, a także odbudowy i regeneracji miast. Obecnie kontakty partnerskie miast pojawiają się z różnych względów: podobnej nazwy, historycznych powiązań lub podobieństw infrastrukturalnych. Celem tej pracy było usystematyzowanie dotychczasowych badań nad ideą miast partnerskich oraz określenie jej oddziaływania na rozwój współczesnego miasta na przykładzie średniego miasta w Polsce – Leszna. Wykorzystano wyniki autorskich badań ankietowych przeprowadzonych wśród reprezentantów leszczyńskiego pokolenia Z oraz wywiadów z przedstawicielami samorządu i biznesu. Stwierdzono, że aktywne uczestnictwo w relacjach z miastami partnerskimi ma pozytywne efekty i sprzyja rozwojowi współczesnych miast.The idea of sister cities is actually a result of the processes initiated after the Second World War. The new post-war reality prompted more and more cities to establish partnerships to avoid further conflicts, as well as to rebuild and regenerate. Nowadays, cities create such contacts for various reasons: similar name, historical links or infrastructural similarities. The paper aims to systematize the existing knowledge on the idea of sister cities and to determine the influence of the discussed idea on contemporary city development. The example was a medium-sized city in Poland – Leszno. Results of survey conducted among the generation Z representatives and interviews with self-government and business representatives were used in the paper. The author found that active participation in relations with sister cities has positive effects on the development of the engaged cities