Gravitational Couplings of Higher Spins from String Theory

We calculate the interaction 3-vertex of two massless spin 3 particles with a graviton using vertex operators for spin 3 fields in open string theory, constructed in our previous work. The massless spin 3 fields are shown to interact with the graviton through the linearized Weyl tensor, reproducing the result by Boulanger, Leclercq and Sundell. This is consistent with the general structure of the non-Abelian $2-s-s$ couplings, implying that the minimal number of space-time derivatives in the interaction vertices of two spin s and one spin 2 particle is equal to $2s-2$.Comment: 19 page

Agency, Liberation, and Intersectionality among Latina Scholars: Narratives from a Cross-institutional Writing Collective

Among United States residents, the number of doctoral degrees conferred to Latinx students represents a small percentage compared to other groups. For example, from 2009–2010, the percentage of degrees conferred to Latinx students was 5 percent compared to 74 percent for White students, 11 percent for Asian/Pacific Islanders, 7 percent for African Americans, and 0.7 percent for Indian/Alaska Natives. During the same period, the proportion of doctoral degrees conferred to females was 55 percent for Latinas compared to 65 percent for African American students, 56 percent for Asian/Pacific students, 54 percent for American Indian/Alaska Native students, and 51 percent for White female students (National Center for Education Statistics). Historically, underrepresented minority (URM) students encounter a plethora of issues that influence their educational experiences, yet there is a scarcity of scholarship that elucidates the quality of experience of women of color (WOC) pursuing doctorate degrees (Aryan and Guzman). As multi-marginalized, firstgeneration college students, we continuously struggle to find a place within higher education. Our educational pathways to becoming doctoral recipients have occurred primarily within the context of alienation, significantly influencing our need to connect with other WOC who have also felt isolated and disconnected. Consequently, we needed to find each other because knowing that there were other Latinas in doctoral programs, and actually getting to know them, validated our existence within academiaUniversity Writing Cente

On the relation between local and geometric Lagrangians for higher spins

Equations of motion for free higher-spin gauge fields of any symmetry can be formulated in terms of linearised curvatures. On the other hand, gauge invariance alone does not fix the form of the corresponding actions which, in addition, either contain higher derivatives or involve inverse powers of the d'Alembertian operator, thus introducing possible subtleties in degrees of freedom count. We suggest a path to avoid ambiguities, starting from local, unconstrained Lagrangians previously proposed, and integrating out the auxiliary fields from the functional integral, thus generating a unique non-local theory expressed in terms of curvatures.Comment: 14 pages. Contribution to the proceedings of the 1st Mediterranean Conference on Classical and Quantum Gravity, Kolymbary (Crete, Greece) September 14-18 200

Exact renormalization group equation in presence of rescaling anomaly II - The local potential approximation

Exact renormalization group techniques are applied to mass deformed N=4 supersymmetric Yang-Mills theory, viewed as a regularised N=2 model. The solution of the flow equation, in the local potential approximation, reproduces the one-loop (perturbatively exact) expression for the effective action of N=2 supersymmetric Yang-Mills theory, when the regularising mass, M, reaches the value of the dynamical cutoff. One speculates about the way in which further non-perturbative contributions (instanton effects) may be accounted for.Comment: 13 pages, no figures, uses JHEP3.cl

Maxwell-like Lagrangians for higher spins

We show how implementing invariance under divergence-free gauge transformations leads to a remarkably simple Lagrangian description of massless bosons of any spin. Our construction covers both flat and (A)dS backgrounds and extends to tensors of arbitrary mixed-symmetry type. Irreducible and traceless fields produce single-particle actions, while whenever trace constraints can be dispensed with the resulting Lagrangians display the same reducible, multi-particle spectra as those emerging from the tensionless limit of free open-string field theory. For all explored options the corresponding kinetic operators take essentially the same form as in the spin-one, Maxwell case.Comment: 77 pages, revised version. Erroneous interpretation and proof of the gauge-fixing procedure for mixed-symmetry fields corrected. As a consequence, the mixed-symmetry, one-particle Lagrangians are to be complemented with conditions on the divergences of the fields; all other conclusions unchanged. Additional minor changes including references added. To appear in JHE

The storm-time ring current: a statistical analysis at two widely separated low-latitude stations

We conducted a statistical analysis of the geomagnetic field variations during the storm main phase at two low-latitude stations, separated by several hours in magnetic local time, in order to investigate the asymmetry and longitudinal extent of the storm-time ring current. The results show evidence for an asymmetric current which typically extends from evening to noon and, during moderate solar wind electric field conditions, up to the early morning, confirming the important role of the magnetospheric convection in the ring current energization. We also analyzed a possible relationship between the local current intensity during the storm main phase and the substorm activity observed at different time delays τ with respect to the storm onset. The results show a significant anticorrelation for τ =-1h, indicating that if the substorm activity is high just before the storm, a weaker ring current develops

A Qualitative Investigation into Contemporary Experiences of Immigrant Young Adults with a Deferred Action for Childhood Arrivals (DACA) Status: Experiences of Stress, Socio-political Shifts, and Impacts on Health and Wellbeing

In 2012, President Barack Obama used prosecutorial discretion to initiate the Deferred Action for Childhood Arrivals (DACA) program that deferred deportation and provided employment authorization for a two-year renewable period to undocumented immigrant persons that came to the U.S. as children. Under former President Donald Trump’s administration, DACA was rescinded in 2017. A review of the literature suggests this is the only study to explore the perceived impact of a policy shift in DACA status, given the critical time of interviews conducted from April 2016 to October 2018. Thus, substantially advancing the literature, qualitative data on a diverse group (N=10) of young adult DACA beneficiaries revealed positive and negative impacts. The sample included 60% currently gainfully employed, 40% attending college—while 80% had experienced emotional distress by having an unauthorized legal status and facing obstacles to pursuing higher education. Of note, 40% rated themselves as currently relatively healthy, while 60% indicated having experienced a decline in their physical or mental health since entering the United States. As significant sources of stress, 90% had experienced anxiety centered around having to wait to renew their DACA status and having to pay for their status renewals. Given the rescinding of the DACA program in 2017, many were ill-prepared, as 90% had never experienced being undocumented without a DACA status as an adult in the United States. The main body of qualitative data generated six categories that encompassed 51 emergent themes: 1-Participants’ health trajectory across their lifespan; 2-Participants’ experiences of barriers to seeking care and having their health and mental health needs addressed; 3-Participants Living at the Intersection of Contemporary Immigration; 4-The impact of other family members’ immigration status; 5-From enjoying benefits of the DACA program, to having a false sense of normalcy, to feeling ambivalence, and experiencing detriments; and, 6-Potential DACA policy shifts and anticipated impacts ranging from negative (fear, loss, suffering) to positive (relief). These six broad categories suggest how, despite the benefits of their DACA status, substantial barriers and sources of anxiety and stress still impacted the lives of the young adults and their families. Implications of the findings are discussed

A structured index describing the ease of disassembly for handcrafted product

Both economic and environmental aspects significantly influence the design process since the early phases of preliminary design. The total Life Cycle Assessment (LCA) and the End of Life (EoL) of products have to be defined in the early design phases too but, for industrial products that are not feasible to automatic production, they are hard issues. However, the EoL of products can be assessed by evaluating the disassembly of joints assembling the product, even when the production process is subject to an important contribute of workmanship. In this paper, a useful method is proposed to analyze the disassembly plant of products, in order to optimize the design process in the early preliminary phases. The method quantitatively evaluates a Disassembly Index that describes the attitude of a product to be disassembled. A case study describes the disassembly attitude of structural subassemblies of a sailboat. In order to test the applicability of the model described to both manual and automated disassembly, a further application of the method is proposed on a Computer CPU. As result, the model demonstrated good sensitiveness to the testing of products quite different for dimensions, number of components, manufacturing processes and, in all cases, it quantified the disassembly easiness with good relevance

Análisis del aula especial bajo la perspectiva de la nueva normalidad

Análisis del aula especial bajo la perspectiva de la nueva normalidad. Esta investigación ha tenido como primera intención analizar el aula especial bajo la perspectiva de la nueva normalidad en la Escuela Bilingüe Berta Elida Fernández y a su vez describir la percepción del docente de Educación Especial ante el entorno virtual desde un diseño no experimental de tipo mixta y transversal. Para la realización de este estudio se ha utilizado una muestra probabilística. Los análisis de resultados de este estudio muestran que los padres de familia se inclinan más por las clases presenciales que virtuales y que también tienen limitaciones tecnológicas. Además, el docente especial dejó en claro que si ha habido un retroceso en los aprendizajes de sus alumnos y que las clases virtuales no fueron de provecho para todos en igualdad de condiciones

Higher spin interactions with scalar matter on constant curvature spacetimes: conserved current and cubic coupling generating functions

Cubic couplings between a complex scalar field and a tower of symmetric tensor gauge fields of all ranks are investigated on any constant curvature spacetime of dimension d>2. Following Noether's method, the gauge fields interact with the scalar field via minimal coupling to the conserved currents. A symmetric conserved current, bilinear in the scalar field and containing up to r derivatives, is obtained for any rank r from its flat spacetime counterpart in dimension d+1, via a radial dimensional reduction valid precisely for the mass-square domain of unitarity in (anti) de Sitter spacetime of dimension d. The infinite collection of conserved currents and cubic vertices are summarized in a compact form by making use of generating functions and of the Weyl/Wigner quantization on constant curvature spaces.Comment: 35+1 pages, v2: two references added, typos corrected, enlarged discussions in Subsection 5.2 and in Conclusion, to appear in JHE