Leptonic Invariants, Neutrino Mass-Ordering and the Octant of θ23\theta_{23}

We point out that leptonic weak-basis invariants are an important tool for the study of the properties of lepton flavour models. In particular, we show that appropriately chosen invariants can give a clear indication of whether a particular lepton flavour model favours normal or inverted hierarchy for neutrino masses and what is the octant of $\theta_{23}$. These invariants can be evaluated in any conveniently chosen weak-basis and can also be expressed in terms of neutrino masses, charged lepton masses, mixing angles and CP violation phases.Comment: 10 pages, no figure

Non-Factorizable Phases, Yukawa Textures and the Size of sin (2 beta)

We emphasize the crucial r\^ ole played by non-factorizable phases in the analysis of the Yukawa flavour structure performed in weak bases with Hermitian mass matrices and with vanishing $(1,1)$ entries. We show that non-factorizable phases are important in order to generate a sufficiently large $\sin 2 \beta$. A method is suggested to reconstruct the flavour structure of Yukawa couplings from input experimental data both in this Hermitian basis and in a non-Hermitian basis with a maximal number of texture zeros. The corresponding Froggatt--Nielsen patterns are presented in both cases.Comment: 15 pages, 3 figure

Quasidegeneracy of Majorana Neutrinos and the Origin of Large Leptonic Mixing

We propose that the observed large leptonic mixing may just reflect a quasidegeneracy of three Majorana neutrinos. The limit of exact degeneracy of Majorana neutrinos is not trivial, as leptonic mixing and even CP violation may occur. We conjecture that the smallness of $|U_{13}|$, when compared to the other elements of $U_{PMNS}$, may just reflect the fact that, in the limit of exact mass degeneracy, the leptonic mixing matrix necessarily has a vanishing element. We show that the lifting of the mass degeneracy can lead to the measured value of $|U_{13}|$ while at the same time accommodating the observed solar and atmospheric mixing angles. In the scenario we consider for the breaking of the mass degeneracy there is only one CP violating phase, already present in the limit of exact degeneracy, which upon the lifting of the degeneracy generates both Majorana and Dirac-type CP violation in the leptonic sector. We analyse some of the correlations among physical observables and point out that in most of the cases considered, the implied strength of leptonic Dirac-type CP violation is large enough to be detected in the next round of experiments.Comment: 16 pages, 4 figures. Matches published version, references added, improved discussion, results unchange

What if the Masses of the First Two Quark Families are not Generated by the Standard Higgs?

We point out that, in the context of the SM, $|V^2_{13}| + | V^2_{23}|$ is expected to be large, of order one. The fact that $|V^2_{13}| + |V^2_{23}| \approx 1.6 \times 10^{-3}$ motivates the introduction of a symmetry S which leads to $V_{CKM} ={1\>\!\!\!\mathrm{I}}$, with only the third generation of quarks acquiring mass. We consider two scenarios for generating the mass of the first two quark generations and full quark mixing. One consists of the introduction of a second Higgs doublet which is neutral under S. The second scenario consists of assuming New Physics at a high energy scale , contributing to the masses of light quark generations, in an effective field theory approach. This last scenario leads to couplings of the Higgs particle to $s\overline s$ and $c \overline c$ which are significantly enhanced with respect to those of the SM. In both schemes, one has scalar-mediated flavour- changing neutral currents which are naturally suppressed. Flavour violating top decays are predicted in the second scenario at the level \mbox{Br} (t \rightarrow h c ) \geq 5\times 10^{-5}.Comment: 11 pages, 1 figur

Yukawa Textures, New Physics and Nondecoupling

We point out that New Physics can play an important r\^ ole in rescuing some of the Yukawa texture zero ans\" atze which would otherwise be eliminated by the recent, more precise measurements of $V_{CKM}$. As an example, a detailed analysis of a four texture zero ansatz is presented, showing how the presence of an isosinglet vector-like quark which mixes with standard quarks, can render viable this Yukawa texture. The crucial point is the nondecoupling of the effects of the isosinglet quark, even for arbitrary large values of its mass.Comment: 13 pages, no figure

Working time and digital transition: A complex and ambiguous relationship

The digital transition underway combines different types of technology: digital, physical and biological. These three families of technologies interact, drawing on the progress in artificial intelligence and machine learning, and creating the opportunity of digitalizing all stages of production and services systems. The increase of digital work represents a deep transformation of economy and society, posing huge challenges to companies, employees and policy makers, and therefore to social scientists. In this context, in European countries, working time regulation has become central to employment policies. The guiding principles of working time management are based on three aspects: the conventional definition of working time flexibility; the development of public measures that aim at making the reduction of working hours advantageous; and the adequacy of working time management to the whole of working life. Advances in information and communication technologies that bring high convenience to personal life are also blurring the lines of work-time and personal time, threatening work-life balance. This situation is raising not only important legal issues, but also ethical considerations related to mandatory or unpaid overtime, and the possibility of employer subtle or explicit coercion. Additionally, the ethicality of unconventional shift work and long work-hour schedules is also at stake in issues like the gender-based inequities related to working hours, and employers' responsibilities for protecting individuals who are not employees from the indirect effects of demanding work schedules, namely affecting the work-family balance. In terms of research methods, after an assessment of the transformations underway, based on literature review and documentary analysis, we will develop a qualitative approach with semi-structured interviews, which will allow to analyse the position of different key actors (employers' and trade union confederations) on long working hours and their effects.info:eu-repo/semantics/acceptedVersio

Vector-like Quarks at the Origin of Light Quark Masses and Mixing

We show how a novel fine-tuning problem present in the Standard Model can be solved through the introduction of a single flavour symmetry G, together with three $Q = - 1/3$ quarks, three $Q = 2/3$ quarks, as well as a complex singlet scalar. The symmetry G is extended to the additional fields and it is an exact symmetry of the Lagrangian, only spontaneously broken by the vacuum. Specific examples are given and a phenomenological analysis of the main features of the model is presented. It is shown that even for vector-like quarks with masses accessible at the LHC, one can have realistic quark masses and mixing, while respecting the strict constraints on process arising from flavour changing neutral currents (FCNC). The vector-like quark decay channels are also described.Comment: 25 pages, no figure

COVID-19, digital transformation and the expansion of telework in Portugal

The COVID-19 pandemic has dramatically exposed the limits of globalization and the fragility of our societies. On the other hand, it has also accelerated the pace of the digital transformation underway (Schwab, 2016). Notwithstanding the subsequent deep economic crisis, the resilience revealed by the society and the economy owes a lot to a vast range of solutions based in telecommunications and ICT in work organization, services, sales, education and telemedicine. The rapid extension of teleworking represents a major change that is likely to be not fully reversed after the pandemic. In addition to the benefits provided in averting a dramatic blockade (stoppage) of the system, it has also revealed or deepen inequalities among workers, between those who may work from home with adequate access to digital devices and those who cannot. Work-life balance is both a major objective for employees and a big challenge for enterprises. Teleworking may contribute to this balance. It occupies a central place in EU social policies, especially related with the working environment and organization associated with work-life balance, health, performance and workers' perspectives (Eurofound, 2020). In this paper, we will address theoretically and empirically the extension of teleworking and its socioeconomic, legal, and ethical impacts in advanced countries, with a particular focus on the Portuguese case. We will draw on official data and recent surveys carried out by the European Commission agencies, the OECD, the Portuguese Statistical Office, and other entities, such as research institutions, international consultancy companies and employers’ organizations. We will also analyze the return to face-to-face activity after many workers have experienced the flexibility of working from home. These changes may strongly influence the shape of work organization and labour markets landscape in the short-term an in the future and affect society and economy as a whole (Huws, 2017; ILO, 2020).info:eu-repo/semantics/publishedVersio

An investigation of pricing strategies within simplex

The PRICE step within the revised simplex method for the LP problems is considered in this report. Established strategies which have proven to be computationally efficient are first reviewed. A method based on the internal rate of return is then described. The implementation of this method and the results obtained by experimental investigation are discussed