13 research outputs found
Tensionless Tales of Compactification
We study circle compactifications of tensionless bosonic string theory, both
at the classical and the quantum level. The physical state condition for
different representations of BMS, the worldsheet residual gauge symmetry
for tensionless strings, admits three inequivalent quantum vacua. We obtain the
compactified mass spectrum in each of these vacua using canonical quantization
and explicate their properties.Comment: 55 page
N spike D-strings in AdS Space with mixed flux
We use Dirac-Born-Infeld action to study the spinning D-string in
background in the presence of both NS-NS and RR fluxes. We compute the scaling
relation between the energy (E) and spin (S) in the `long string limit'. The
energy of these spiky string is found to be a function of spin with the leading
logarithmic behaviour and the scaling relation appears to be independent of the
amount of flux present. We further discuss folded D-string solutions in
background with pure NS-NS and R-R fluxes.Comment: 27 pages, 12 figure
Neumann-Rosochatius system for strings on I-brane
We study rigidly rotating and pulsating strings in the background of a 1+1
dimensional intersection of two orthogonal stacks of fivebranes in type IIB
string theory by using the Neumann-Rosochatius (NR) model. Starting with the
Polyakov action of the probe fundamental string we show that a generalised
ansatz reduce the system into the one dimensional NR model in the presence of
flux. The integrable construction of the model is exploited to analyze the
rotating and oscillating string solution. We render the large BMN-type
expansion for the energy of rotating string states while the same for the
oscillating string has been derived in long string and small angular momenta
limit.Comment: 18 page
Neumann-Rosochatius system for rotating strings in with flux
Strings on with mixed flux exhibit
exact integrability. We wish to construct an integrable Neumann-Rosochatius
(NR) model of strings starting with the type IIB supergravity action in with pure NSNS flux. We observe that the forms
of the Lagrangian and the Uhlenbeck integrals of motion of the considered
system are NR-like with some suitable deformations which eventually appear due
to the presence of flux. We utilize the integrable framework of the deformed NR
model to analyze rigidly rotating spiky strings moving only in .
We further present some mathematical speculations on the rounding-off nature of
the spike in the presence of non-zero angular momentum in .Comment: 24 page
Tensionless tales of compactification
Abstract We study circle compactifications of tensionless bosonic string theory, both at the classical and the quantum level. The physical state condition for different representations of BMS3, the worldsheet residual gauge symmetry for tensionless strings, admits three inequivalent quantum vacua. We obtain the compactified mass spectrum in each of these vacua using canonical quantization and explicate their properties
Neumann-Rosochatius system for strings on I-brane
Abstract We study rigidly rotating and pulsating strings in the background of a 1+1 dimensional intersection of two orthogonal stacks of fivebranes in type IIB string theory by using the Neumann-Rosochatius (NR) model. Starting with the Polyakov action of the probe fundamental string we show that a generalised ansatz reduce the system into the one dimensional NR model in the presence of flux. The integrable construction of the model is exploited to analyze the rotating and oscillating string solution. We render the large J BMN-type expansion for the energy of rotating string states while the same for the oscillating string has been derived in long string and small angular momenta limit
Neumann-Rosochatius system for rotating strings in AdS 3 Ă— S 3 Ă— S 3 Ă— S 1 with flux
Abstract We wish to construct an integrable Neumann-Rosochatius (NR) model of strings in AdS 3 Ă— S 3 Ă— S 3 Ă— S 1 supported by pure NSNS flux. We observe that the forms of the Lagrangian and the Uhlenbeck integrals of motion of the considered system are NR-like with some suitable deformations, which eventually appear due to the presence of flux. We utilize the integrable framework of the deformed NR model to analyze rigidly rotating spiky strings moving only in S 3 Ă— S 1. We further present a quantitative study on the rounding-off nature of the spike in the presence of non-zero angular momentum J in S 1
ViSHWaS: Violence Study of Healthcare Workers and Systems—a global survey
Objective To provide insights into the nature, risk factors, impact and existing measures for reporting and preventing violence in the healthcare system. The under-reporting of violence against healthcare workers (HCWs) globally highlights the need for increased public awareness and education.Methods The Violence Study of Healthcare Workers and Systems study used a survey questionnaire created using Research Electronic Data Capture (REDCap) forms and distributed from 6 June to 9 August 2022. Logistic regression analysis evaluated violence predictors, including gender, age, years of experience, institution type, respondent profession and night shift frequency. A χ2 test was performed to determine the association between gender and different violence forms.Results A total of 5405 responses from 79 countries were analysed. India, the USA and Venezuela were the top three contributors. Female respondents comprised 53%. The majority (45%) fell within the 26–35 age group. Medical students (21%), consultants (20%), residents/fellows (15%) and nurses (10%) constituted highest responders. Nearly 55% HCWs reported firsthand violence experience, and 16% reported violence against their colleagues. Perpetrators were identified as patients or family members in over 50% of cases, while supervisor-incited violence accounted for 16%. Around 80% stated that violence incidence either remained constant or increased during the COVID-19 pandemic. Among HCWs who experienced violence, 55% felt less motivated or more dissatisfied with their jobs afterward, and 25% expressed willingness to quit. Univariate analysis revealed that HCWs aged 26–65 years, nurses, physicians, ancillary staff, those working in public settings, with >1 year of experience, and frequent night shift workers were at significantly higher risk of experiencing violence. These results remained significant in multivariate analysis, except for the 55–65 age group, which lost statistical significance.Conclusion This global cross-sectional study highlights that a majority of HCWs have experienced violence, and the incidence either increased or remained the same during the COVID-19 pandemic. This has resulted in decreased job satisfaction