A5081386050- Pulsars and Gravitational Waves Research
- Cosmology and Gravitation Theories
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Black Holes and Theoretical Physics
- Geophysics and Gravity Measurements
- Noncommutative and Quantum Gravity Theories
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Advanced Mathematical Theories and Applications
- Radio Astronomy Observations and Technology
- Radioactivity and Radon Measurements
- High-pressure geophysics and materials
- Seismic Waves and Analysis
- Galaxies: Formation, Evolution, Phenomena
- Graphite, nuclear technology, radiation studies
- Nuclear and radioactivity studies
- Relativity and Gravitational Theory
- Airway Management and Intubation Techniques
- Astrophysics and Cosmic Phenomena
- Earthquake Detection and Analysis
- Astrophysical Phenomena and Observations
- Respiratory Support and Mechanisms
- Radiation Detection and Scintillator Technologies
- earthquake and tectonic studies
University of Cape Town
2022-2024
Indian Institute of Science Bangalore
2018-2023
University of Central Thailand
2022-2023
Interaction Institute for Social Change
2021
University of Alabama at Birmingham
2011
AGH University of Krakow
1996
Endotracheal tube cuff pressure must be kept within an optimal range that ensures ventilation and prevents aspiration while maintaining tracheal perfusion.To test the effect of intervention (adding or removing air) on proportion time was between 20 30 cm H(2)O to evaluate changes in over time.A repeated-measure crossover design used study 32 orally intubated patients receiving mechanical for two 12-hour shifts (randomized control conditions). Continuous monitoring initiated, adjusted a...
Recent observations of several peculiar over- and underluminous type Ia supernovae infer indirect evidence for the violation Chandrasekhar mass limit by suggesting existence super- sub-Chandrasekhar limiting white dwarfs. In an attempt to explain these phenomena in context general relativistic extensions, we study objects Palatini $f(R)$ gravity. We obtain masses as well dynamical instability criteria dwarfs given gravitational theory. further demonstrate that conventional positivity...
We analyze the effects of modified gravity on specific heats electrons and ions, Debye temperature, crystallization process, cooling mechanism in white dwarfs. derive Lane-Emden-Chandrasekhar equation relate it to process equations for Palatini $f(R)$ gravity. Moreover, first time literature, we show that model plays a crucial role not only mass size dwarf, but also affects their internal properties. further demonstrate can decrease age significantly.
ABSTRACT Recent detection of gravitational wave from nine black hole merger events and one neutron star event by LIGO VIRGO shed a new light in the field astrophysics. On other hand, past decade, few super-Chandrasekhar white dwarf candidates have been inferred through peak luminosity curves peculiar Type Ia supernovae, though there is no direct these objects so far. Similarly, number stars with mass $>\! 2\, \mathrm{M}_\odot$ also observed. Continuous can be alternate ways to detect...
In recent years, the idea of sub- and super-Chandrasekhar limiting mass white dwarfs (WDs), which are potential candidates to produce under- over-luminous type Ia supernovae, respectively, has been a key interest in scientific community. Although researchers have proposed different models explain these peculiar objects, modified theories Einstein's gravity, particularly f(R) gravity with R being scalar curvature, seem be one finest choices both regimes WDs. It was already shown that...
Abstract After the prediction of many sub- and super-Chandrasekhar (at least a dozen for latter) limiting-mass white dwarfs (WDs), hence apparently peculiar class WDs, from observations luminosity Type Ia supernovae, researchers have proposed various models to explain these two classes WD separately. We earlier showed that WD, along with regular can be explained by single form f ( R ) gravity, whose effect is significant only in high-density regime, it almost vanishes low-density regime....
There are currently two open questions in white dwarf physics: why massive dwarfs observed less often astronomical surveys, and have not any super-Chandrasekhar been found despite the discovery of more than a dozen peculiar, overly-luminous type Ia supernovae about couple decades? According to different research, magnetic fields appear somewhat resolve these issues, but stability remains concern. For first time, we investigate how modified gravity affects specific heat electrons ions,...
Abstract A number of recent observations have suggested that the Einstein’s theory general relativity may not be ultimate gravity. The f ( R ) gravity model with being scalar curvature turns out to one best bet surpass which explains a phenomena where fails. In gravity, behaviour spacetime is modified as compared given by relativity. This has already been explored for understanding various compact objects such neutron stars, white dwarfs etc. and also describing evolution universe. Although...
Since the unexpected discovery of fast radio bursts (FRBs), researchers have proposed varied theories and models to explain these phenomena. One such model that has recently been developed incorporates so-called Gertsenshtein-Zel'dovich (GZ) effect, which states when gravitational waves traverse a pulsar magnetosphere, portion radiation is transformed into electromagnetic (EM) radiation. The observed properties FRBs are consistent with this EM radiation, implying, remarkably, GZ effect can...
Abstract Over the last few decades, a plethora of modifications to general relativity have been proposed solve host cosmological and astrophysical problems. Many modified gravity models are now ruled out with further observations; some theories still viable, with, at best, bounds on their parameters set by observations date. More recently, Fast Radio Bursts proven be remarkably powerful tools constrain cosmology fundamental physics. In this work, we consider generic theory implications for...
Type Ia supernovae (SNeIa), used as one of the standard candles in astrophysics, are believed to form when mass white dwarf approaches Chandrasekhar limit. However, observations last few decades detected some peculiar SNeIa, which predicted be originating from dwarfs much less than limit or higher it. Although unification these two sub-classes SNeIa was attempted earlier by our group, this work, we, for first time, explain phenomenon terms just property is its central density. Thereby we do...
The indirect evidence for at least a dozen massive white dwarfs (WDs) violating the Chandrasekhar mass limit is considered to be one of wonderful discoveries in astronomy more than decade. Researchers have already proposed diverse amount models explain this astounding phenomenon. However, each these always carries some drawbacks. On other hand, noncommutative geometry best replicas quantum gravity, which yet proved from observations. Madore introduced idea fuzzy sphere describe formalism...
A simple cooling model of white dwarf stars is re-analyzed in Palatini f(R) gravity. Modified gravity affects the structures and consequently their ages. We find that resulting super-Chandrasekhar dwarfs need more time to cool down than sub-Chandrasekhar ones, or when compared Newtonian models.
Various experiments and observations have led researchers to suggest different bounds on fundamental constants like the fine-structure constant proton-to-electron mass ratio. These differ mostly due energy scale of systems where are performed. In this article, we obtain these parameters in modified gravity context using Gaia-DR2 massive white dwarf data show that alter as theory changes. This exploration not only indicates strong support for non-negligible influences astrophysical scenarios...
Abstract Over the past two decades, inference of violation Chandrasekhar mass limit white dwarfs (WDs) from indirect observation has been a revolutionary discovery in astronomy. Various researchers have already proposed different theories to explain this interesting phenomenon. However, such massive WDs usually possess very little luminosity, hence they so far cannot be detected directly by any observations. We that continuous gravitational wave may one probes detect them directly, and...
ABSTRACT Fundamental constants are crucial for comprehending physical mechanisms, but their measurements contain uncertainties due to experimental limitations. We investigate the impact of system temperature on these using nearby white dwarfs observed in Gaia Early Data Release 3 (EDR3) survey. Using structures dwarfs, we show that variation can affect accuracy fundamental parameters such as fine-structure constant and proton-to-electron mass ratio. This exploration emphasizes importance...
Abstract Few and sporadic measurements are so far available on the characteristics of indoor radon thoron daughters in typical Mediterranean areas. For this reason, a pilot study is being carried out Rome, to equilibrium factor F influence ventilation rates realistic domestic environments. Preliminary data show both significant Rn Tn daughter concentration non-negligible contribution annual effective dose inhabitants.
Chandrasekhar made the startling discovery about nine decades back that mass of compact object white dwarf has a limiting value, once nuclear fusion reactions stop therein. This is mass-limit, which $\sim1.4M_\odot$ for non-rotating non-magnetized dwarf. On approaching this mass, believed to spark off with an explosion called type Ia supernova, considered be standard candle. However, observations several over-luminous, peculiar supernovae indicate mass-limit significantly larger. By...
ABSTRACT More than two dozen soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars (AXPs) have been detected so far. These are isolated compact objects. Many of them either found to be associated with supernova remnants or their surface magnetic fields directly measured, confirming that they neutron stars (NSs). However, it has argued some SGRs AXPs highly magnetized white dwarfs (WDs). Meanwhile, the existence super-Chandrasekhar WDs remained a puzzle. not even single such massive WD...
There are currently two open questions in white dwarf physics: why massive dwarfs observed less often astronomical surveys, and have not any super-Chandrasekhar been found despite the discovery of more than a dozen peculiar, overly-luminous type Ia supernovae about couple decades? According to different research, magnetic fields appear somewhat resolve these issues, but stability remains concern. For first time, we investigate how modified gravity affects specific heat electrons ions,...
It is shown that the dust density regimes in dusty plasma are characterized by two complementary screening processes, (a) low regime where Debye dominant process and (b) high Coulomb process. The a state all particles carry an equal constant charge. high-density or charge depends on spatial location screened other vicinity reduction, quark like asymptotic freedom particles, which average minimal electric (q tends to 0), asymptotically free, (c) uniform potential, (d) neutralization...