Hunting for the New Symmetries in Calabi-Yau Jungles

It was proposed that the Calabi-Yau geometry can be intrinsically connected with some new symmetries, some new algebras. In order to do this it has been analyzed the graphs constructed from K3-fibre CY_d (d \geq 3) reflexive polyhedra. The graphs can be naturally get in the frames of Universal Calabi-Yau algebra (UCYA) and may be decode by universal way with changing of some restrictions on the generalized Cartan matrices associated with the Dynkin diagrams that characterize affine Kac-Moody algebras. We propose that these new Berger graphs can be directly connected with the generalizations of Lie and Kac-Moody algebras.Comment: 29 pages, 15 figure

A Layman's guide to SUSY GUTs

The determination of the most straightforward evidence for the existence of the Superworld requires a guide for non-experts (especially experimental physicists) for them to make their own judgement on the value of such predictions. For this purpose we review the most basic results of Super-Grand unification in a simple and clear way. We focus the attention on two specific models and their predictions. These two models represent an example of a direct comparison between a traditional unified-theory and a string-inspired approach to the solution of the many open problems of the Standard Model. We emphasize that viable models must satisfy {\em all} available experimental constraints and be as simple as theoretically possible. The two well defined supergravity models, $SU(5)$ and $SU(5)\times U(1)$, can be described in terms of only a few parameters (five and three respectively) instead of the more than twenty needed in the MSSM model, \ie, the Minimal Supersymmetric extension of the Standard Model. A case of special interest is the strict no-scale $SU(5)\times U(1)$ supergravity where all predictions depend on only one parameter (plus the top-quark mass). A general consequence of these analyses is that supersymmetric particles can be at the verge of discovery, lurking around the corner at present and near future facilities. This review should help anyone distinguish between well motivated predictions and predictions based on arbitrary choices of parameters in undefined models.Comment: 25 pages, Latex, 11 figures (not included), CERN-TH.7077/93, CTP-TAMU-65/93. A complete ps file (1.31MB) with embedded figures is available by request from [email protected]

Towards an Algebraic Classification of Calabi-Yau Manifolds; 1, Study of K3 Spaces

We present an inductive algebraic approach to the systematic construction andclassification of generalized Calabi-Yau (CY) manifolds in different numbers ofcomplex dimensions, based on Batyrev's formulation of CY manifolds as toricvarieties in weighted complex projective spaces associated with reflexivepolyhedra. We show how the allowed weight vectors in lower dimensions may beextended to higher dimensions, emphasizing the roles of projection andintersection in their dual description, and the natural appearance ofCartan-Lie algebra structures. The 50 allowed extended four-dimensional vectorsmay be combined in pairs (triples) to form 22 (4) chains containing 90 (91) K3spaces, of which 94 are distinct, and one further K3 space is found usingduality. In the case of CY_3 spaces, pairs (triples) of the 10~270 allowedextended vectors yield 4242 (259) chains with K3 (elliptic) fibers containing730 additional K3 polyhedra. A more complete study of CY_3 spaces is left forlater work

Universal Calabi-Yau Algebra: Classification and Enumeration of Fibrations

We apply a universal normal Calabi-Yau algebra to the construction and classification of compact complex $n$-dimensional spaces with SU(n) holonomy and their fibrations. This algebraic approach includes natural extensions of reflexive weight vectors to higher dimensions and a `dual' construction based on the Diophantine decomposition of invariant monomials. The latter provides recurrence formulae for the numbers of fibrations of Calabi-Yau spaces in arbitrary dimensions, which we exhibit explicitly for some Weierstrass and K3 examples

Results from an Algebraic Classification of Calabi-Yau Manifolds

We present results from an inductive algebraic approach to the systematic construction and classification of the `lowest-level' CY3 spaces defined as zeroes of polynomial loci associated with reflexive polyhedra, derived from suitable vectors in complex projective spaces. These CY3 spaces may be sorted into `chains' obtained by combining lower-dimensional projective vectors classified previously. We analyze all the 4242 (259, 6, 1) two- (three-, four-, five-) vector chains, which have, respectively, K3 (elliptic, line-segment, trivial) fibres, yielding 174767 (an additional 6189, 1582, 199) distinct projective vectors that define reflexive polyhedra and thereby CY3 spaces, for a total of 182737. These CY3 spaces span 10827 (a total of 10882) distinct pairs of Hodge numbers h_11, h_12. Among these, we list explicitly a total of 212 projective vectors defining three-generation CY3 spaces with K3 fibrations, whose characteristics we provide

Tackling Fuel Poverty in London

The challenge of economic and health inequalities caused by fuel poverty are rooted in the rise in fuel costs which have strong implications affecting the cost of living. Fuel costs and rising inflation due to economic and political reasons threaten individuals and families who are already struggling financially, putting them in/at risk of fuel poverty. The UK is one of the first countries to define the challenge of households living in fuel poverty prompting necessary actions, policies and interventions. This study presents the results of an empirical investigation following direct enquires to the Greater London Authority (GLA) and all of London boroughs via Freedom of Information (FOI) requests on retrofit interventions, including an overview of financial incentives and planning assessments with an aim to increase the number of home energy upgrades since April 2021. London adopted its own action plan in 2018 to renew its focus and alleviate more than 350,000 households in fuel poverty (GLA, 2018). The assessment and indicator for fuel poverty has changed over time, from the Low Income High Cost (LIHC) to Low Income Low Energy Efficiency (LILEE) indicator in 2021. However, identifying households in fuel poverty remains challenging and some indicators are somewhat disconnected from what is happening on the ground. The findings suggest that there is a need to establish tools and methodologies that are connected to the national and local context. Fuel poverty is affecting people’s health and well-being, particularly those already facing socio-economic and health inequalities. After the COVID pandemic, a political awareness of fuel poverty is found in the Mayoral manifesto, however the Fuel Poverty Action Plan does not have binding targets and is not regularly updated. Current Fuel Poverty Partnership Tasks are focusing on awareness and communication or the urgent support to households already affected, but not in tackling the root causes of fuel poverty in upgrading fuel poor homes. The uptake on retrofits from 2021 is still low and far from reaching 100k homes and the net zero target in 2030 is approaching fast. The study concludes that while LILEE is decreasing other indicators are increasing with rising energy prices. The London Building Stock Model is not widely used by boroughs, and it only maps the Energy Performance Certificate (EPC) rating which is not sufficient to identify households in fuel poverty. Most schemes such as Energy Companies Obligation (ECO) do not specifically target fuel poverty but have a wider scope of retrofit towards net zero. The Mayor of London should explore a new indicator tool by crossing data from LBSM with socio-economic data to identify fuel poor households more accurately. The indicator could potentially include geographical location, building typology (age, etc), socio-economic / demographics, leading to action plan and retrofit strategies

Planck Scale Physics and the Testability of SU(5) Supergravity GUT

GUT scale threshold corrections in minimal SU(5) supergravity grand unification are discussed. It is shown that predictions may be made despite uncertainties associated with the high energy scale. A bound relating the strong coupling constant to the mass scales associated with proton decay and supersymmetry is derived, and a sensitive probe of the underlying theory is outlined. In particular, low energy measurements can in principle determine the presence of Planck scale ($1 / {{\rm M}_{\rm Pl}}$) terms.Comment: 12 pages, REVTeX, 2 figures included in an uuencoded Z-compressed PostScript file. Ready to print PostScript version (with figures) may be picked up at ftp://phys.tamu.edu/urano/planck/paper_prep.p

Patologia em fachadas azulejadas em Aveiro

Mestrado em Engenharia CivilA presente dissertação tem como objetivo principal, o estudo, mapeamento e análise da patologia das fachadas azulejadas existentes na cidade de Aveiro, do seu comportamento ao longo do tempo, da durabilidade e da eventual degradação dos azulejos bem como das suas diversas causas, enquanto revestimentos tendencialmente impermeáveis em fachadas de edifícios, assim como algumas diretrizes sobre a conservação e restauro de azulejaria notável.The main objective of the present dissertation is the study, mapping and analysis of the pathology associated with glazed tile facades in the city of Aveiro. This includes their behaviour over time, the durability and possible deterioration of the tiles as waterproof wall coverings on building facades, as well as the various causes of these occurrences. In addition, the dissertation discusses some guidelines with regard to the conservation and restoration of notable tile work.La présente thèse a comme objectif principal l’étude, la cartographie et l’analyse des pathologie des façades revêtues de carreaux de faïence mosaïque dans la ville de ‘’Aveiro’’, de leur comportement au long des années passées, de leur durabilité et leur éventuelle dégradation et de leurs diverses causes, en tant que revêtements tendanciellement imperméables sur des façades de bâtiments, ainsi que les lignes directrices sur la conservation et la restauration remarquable des carreaux de faïence mosaïque.قطانملا ميسقتو ،ةيليصفت ةسارد ءارجإ وه ةحورطألا هذهل يسيئرلا فدهلا فرخزملا فزخلاب ةاطغملا ينابملا تاهجاو يف ةرهاظلا ضارمألا ليلحتو ةيفارغجلا روهدتلا ةيناكمإ وأ لمحتلا ةوقو ،تاونسلا ىدم ىلع هكولس ،’’ورييفأ’‘ ةنيدم يف ءاملا برست دض يماح ءاطغ مهرابتعاب ،هتاببسم فلتخمو تقولا عم يجيردتلا ميمرتو ظفح نأشب ةيهيجوتلا ئدابملا ضعب ءادتقاو ،ينابملا تاهجاو ىلع نمDas Hauptziel dieser Dissertation ist die Studie, Darstellung und Analyse der Pathologie der Fliesenfassaden, die es in der Stadt Aveiro gibt, ihres Verhaltens im Verlauf der Zeit, ihrer Beständigkeit, des eventuellen Zerfalls der Fliesen sowie der diversen Ursachen hierfür als tendenziell wasserdichte Verkleidung an Fassaden und Gebäuden, sowie einige Leitlinien zur Erhaltung dieser außergewöhnlichen Fliesen