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Synchronized gravitational atoms from mergers of bosonic stars

Physical Review D 2020年第10期102卷 101504(R)-101504(R)页

作者： Nicolas Sanchis-Gual Miguel Zilhão Carlos Herdeiro Fabrizio Di Giovanni José A. Font Eugen Radu Centro de Astrofísica e Gravitação—CENTRA Departamento de Física Instituto Superior Técnico—IST Universidade de Lisboa—UL Avenida Rovisco Pais 1 1049-001 Lisbon Portugal Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA) Campus de Santiago 3810-183 Aveiro Portugal Departamento de Astronomía y Astrofísica Universitat de València Dr. Moliner 50 46100 Burjassot (València) Spain Observatori Astronòmic Universitat de València C/ Catedrático José Beltrán 2 46980 Paterna (València) Spain

If ultralight bosonic fields exist in nature as dark matter, superradiance spins down rotating black holes (BHs), dynamically endowing them with equilibrium bosonic clouds, here dubbed synchronized gravitational atoms (SGAs). The self-gravity of these same fields, on the other hand, can lump them into (scalar or vector) horizonless solitons known as bosonic stars (BSs). We show that the dynamics of BSs yield a new channel forming SGAs. We study BS binaries that merge to form spinning BHs. After horizon formation, the BH spins up by accreting the bosonic field, but a remnant lingers around the horizon. If just enough angular momentum is present, the BH spin up stalls precisely as the remnant becomes a SGA. Different initial data lead to SGAs with different quantum numbers. Thus, SGAs may form both from superradiance-driven BH spin down and accretion-driven BH spin up. The latter process, moreover, can result in heavier SGAs than those obtained from the former: in one example herein, ∼18% of the final system’s energy and ∼50% of its angular momentum remain in the SGA. We suggest that even higher values may occur in systems wherein both accretion and superradiance contribute to the SGA formation.

关键词： Classical black holes General relativity equations & solutions

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The dual of convolutional codes over pr

The dual of convolutional codes over pr

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International Conference on Matrix Analysis and its applications, MAT-TRIAD 2015

作者： El Oued, Mohammed Napp, Diego Pinto, Raquel Toste, Marisa High Institute of Maths and Computer Science of Monastir Monastir Tunisia Department of Mathematics CIDMA - Center for Research and Development in Mathematics and Applications University of Aveiro Aveiro Portugal CIDMA - Center for Research and Development in Mathematics and Applications Superior School of Technologies and Management of Oliveira Do Hospital Polytechnic Institute of Coimbra Coimbra Portugal

ISBN: (纸本)9783319499826

An important class of codes widely used in applications is the class of convolutional codes. Most of the literature of convolutional codes is devoted to convolutional codes over finite fields. The extension of the concept of convolutional codes from finite fields to finite rings have attracted much attention in recent years due to fact that they are the most appropriate codes for phase modulation. However convolutional codes over finite rings are more involved and not fully understood. Many results and features that are well-known for convolutional codes over finite fields have not been fully investigated in the context of finite rings. In this paper we focus in one of these unexplored areas, namely, we investigate the dual codes of convolutional codes over finite rings. In particular we study the p-dimension of the dual code of a convolutional code over a finite ring. This contribution can be considered a generalization and an extension, to the ring case, of the work done by Forney and McEliece on the dimension of the dual code of a convolutional code over a finite field. © Springer International Publishing AG 2017.

关键词： Convolutional codes

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SO(2) gauged Skyrmions in 4 + 1 dimensions

arXiv

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arXiv 2020年

作者： Navarro-Lérida, Francisco Radu, Eugen Tchrakian, D.H. Departamento de Física Teórica and IPARCOS Ciencias Físicas Universidad Complutense de Madrid MadridE-28040 Spain Departamento de Matemática da Universidade de Aveiro Center for Research and Development in Mathematics and Applications Campus de Santiago Aveiro3810-183 Portugal School of Theoretical Physics Dublin Institute for Advanced Studies 10 Burlington Road Dublin 4 Ireland Department of Computer Science NUI Maynooth Maynooth Ireland

We study the simplest SO(2) gauged O(5) Skyrme models in 4 + 1 (flat) dimensions. In the gauge decoupled limit, the model supports topologically stable solitons (Skyrmions) and after gauging, the static energy of the solutions is bounded from below by a "baryon number". The studied model features both Maxwell and Maxwell–Chern-Simons dynamics. The considered configurations are subject to bi-azimuthal symmetry in the R4 subspace resulting in a two dimensional subsystem, as well as subject to an enhanced symmetry relating the two planes in the R4 subspace, which results in a one dimensional subsystem. Numerical solutions are constructed in both cases. In the purely magnetic case, fully bi-azimuthal solutions were given, while electrically charged and spinning solutions were constructed only in the radial (enhanced symmetric) case, both in the presence of a Chern-Simons term, and in its absence. We find that, in contrast with the analogous models in 2+1 dimensions, the presence of the Chern-Simons term in the model under study here results only in quantitative effects. Copyright © 2020, The Authors. All rights reserved.

关键词： Topology

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Dynamical bar-mode instability in spinning bosonic stars

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Physical Review D 2020年第12期102卷 124009-124009页

作者： Fabrizio Di Giovanni Nicolas Sanchis-Gual Pablo Cerdá-Durán Miguel Zilhão Carlos Herdeiro José A. Font Eugen Radu Departamento de Astronomía y Astrofísica Universitat de València Dr. Moliner 50 46100 Burjassot (València) Spain Centro de Astrofísica e Gravitação—CENTRA Departamento de Física Instituto Superior Técnico—IST Universidade de Lisboa—UL Avenida Rovisco Pais 1 Lisbon 1049-001 Portugal Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA) Campus de Santiago 3810-183 Aveiro Portugal Observatori Astronòmic Universitat de València C/ Catedrático José Beltrán 2 46980 Paterna (València) Spain

Spinning bosonic stars (SBSs) can form from the gravitational collapse of a dilute cloud of scalar/Proca particles with nonzero angular momentum, via gravitational cooling. The scalar stars are, however, transient due to a nonaxisymmetric instability which triggers the loss of angular momentum. By contrast, no such instability was observed for the fundamental (m=1) Proca stars. In [N. Sanchis-Gual et al., Phys. Rev. Lett. 123, 221101 (2019)] we tentatively related the different stability properties to the different toroidal/spheroidal morphology of the scalar/Proca models. Here, we continue this investigation, using three-dimensional numerical-relativity simulations of the Einstein-(massive, complex)Klein-Gordon system and of the Einstein-(complex)Proca system. First, we incorporate a quartic self-interaction potential in the scalar case to gauge its effect on the instability. Second, we investigate toroidal (m=2) Proca stars to assess their stability. Third, we attempt to relate the instability of SBSs to the growth rate of azimuthal density modes and the existence of a corotation point in the unstable models. Our results indicate that: (a) the self-interaction potential can only delay the instability in scalar SBSs but cannot quench it completely; (b) m=2 Proca stars always migrate to the stable m=1 spheroidal family; (c) unstable m=2 Proca stars and m=1 scalar boson stars exhibit a pattern of frequencies for the azimuthal density modes which crosses the angular velocity profile of the stars in the corotation point. This establishes a parallelism with rotating neutron stars affected by dynamical bar-mode instabilities. Finally, we compute the gravitational waves emitted by SBSs due to the nonaxisymmetric instability. We investigate the detectability of the waveforms comparing the characteristic strain of the signal with the sensitivity curves of a variety of detectors, computing the signal-to-noise ratio for different ranges of masses and for different source dis

关键词： General relativity equations & solutions General relativity formalism Gravitation Gravitational wave sources Gravitational waves Particle dark matter Dynamical systems Numerical relativity

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Optimal annealing temperature of Yersinia enterocolitica ymoA gene primers using the polymerase chain reaction method

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AIP Conference Proceedings 2024年第1期2982卷

作者： M. Nurjayadi G. I. Putri J. L. Declan I. Krisdawati D. A. Juliansyah M. Azzahra I. Maulana I. R. Kartika F. Kurniadewi N. K. Liman T. Fahriza D. Sukmawati S. Rahayu V. Saamia D. A. O. Saputro I. M. Wiranatha H. E. Enshasy Department of Chemistry Faculty of Mathematics and Natural Science Universitas Negeri Jakarta Gedung KH. Hasjim Asj'ari 6th Floor Jl. Rawamangun Muka Jakarta Timur 13220 Indonesia Research Center for Detection of Pathogenic Bacteria Lembaga Penelitian dan Pengabdian Kepada Masyarakat Universitas Negeri Jakarta Jl. Rawamangun Muka Jakarta Timur 13220 Indonesia Department of Biology Faculty of Mathematics and Natural Science Universitas Negeri Jakarta Building KH. Hasjim Asj'ari 9th Floor Rawamangun Muka Street East Jakarta 13220 Indonesia. Center Forensic Laboratory of the Criminal Investigation Police of the Republic of Indonesia Ciapmbuan Babakan Madang Bogor 1681 Indonesia Institute of Bioproduct Development Universiti Teknologi Malaysia (UTM) Skudai Johor Barhru Malaysia. School of Chemical and Energy Engineering Faculty of Engineering Universiti Teknologi Malaysia (UTM) Skudai Johor Bharu Malaysia. City of Scientific Research and Technology Applications New Burg Al Arab Alexandria Egypt.

The case of foodborne diseases has now become a serious global problem. Foodborne diseases occur due to the contamination of pathogenic bacteria. One of the pathogenic bacteria that cause foodborne diseases is Yersinia enterocolitica. This research aimed to determine the annealing temperature of Yersinia enterocolitica ymoA gene primers using the PCR method to ensure that the primers can amplify ymoA gene fragments in Yersinia enterocolitica. In this research, the concentration of DNA as a template used was 70.5 ng/µL with a purity of A260/280 1.88. Optimization of the annealing temperature of Yersinia enterocolitica ymoA gene primers using the Gradient PCR in a range of temperatures between 53°C - 62°C based on the melting temperature value of the ymoA primers. The results of the primers design of the ymoA gene were confirmed to amplify the DNA fragment of Yersinia enterocolitica with an amplicon length of 185 bp. Based on the results, the temperature of 60°C was chosen as the optimum primer annealing temperature for the ymoA gene in Yersinia enterocolitica because only a brightness band was produced from the electrophoresis. This result can be continued with primers testing the ymoA gene on meat samples using the Real-Time PCR method.

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grxB gene as a potential target for the development of Cronobacter sakazakii detection method in infant formula milk using real-time PCR

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AIP Conference Proceedings 2024年第1期2982卷

作者： M. Nurjayadi D. A. Juliansyah J. L. Declan G. I. Putri I. Krisdawati M. Azzahra I. Maulana A. M. A. Putri I. R. Kartika F. Kurniadewi D. Sukmawati S. Rahayu V. Saamia D. A. O. Saputro I. M. Wiranatha H. E. Enshasy Department of Chemistry Faculty of Mathematics and Natural Science Universitas Negeri Jakarta Gedung K.H. Hasjim Asj'ari 6th Floor Jl. Rawamangun Muka Jakarta Timur 13220 Indonesia Research Center for Detection of Pathogenic Bacteria Lembaga Penelitian dan Pengabdian Kepada Masyarakat Universitas Negeri Jakarta Jl. Rawamangun Muka Jakarta Timur 13220 Indonesia Department of Biology Faculty of Mathematics and Natural Science Universitas Negeri Jakarta Building K.H. Hasjim Asj'ari 9th Floor Rawamangun Muka Street East Jakarta 13220 Indonesia. Center Forensic Laboratory of the Criminal Investigation Police of the Republic of Indonesia Ciapmbuan Babakan Madang Bogor 1681 Indonesia Institute of Bioproduct Development Universiti Teknologi Malaysia (UTM) Skudai Johor Barhru Malaysia. School of Chemical and Energy Engineering Faculty of Engineering Universiti Teknologi Malaysia (UTM) Skudai Johor Bharu Malaysia. City of Scientific Research and Technology Applications New Burg Al Arab Alexandria Egypt.

Cronobacter sakazakii is a pathogen that causes necrotizing enterocolitis, sepsis, and meningitis in infants or neonates, with reported case-fatality rates varying from 40 to 80 percent. Therefore, it is necessary to develop fast and accurate detection of C. sakazakii. This study aims to get the primer pairs and optimal annealing temperature for the Polymerase Chain Reaction (PCR) method to detect C. sakazakii. The glutaredoxin B (grxB) gene was found suitable for detecting Cronobacter sakazakii, and a primer pair based on the grxB gene sequence was designed and synthesized. The genomic DNA of Cronobacter sakazakii strain ATCC 29544 was isolated and then used as a template for PCR assay. Optimization of running PCR conditions was carried out by varying the annealing temperature at 53-62°C, and the template DNA concentration of C. sakazakii is 53 ng/µL with a purity (A260/280) of 1,853. The result showed that the primer grxB gave optimal results at the annealing temperature range between 57-61°C and could amplify the grxB C. sakazakii fragment to produce an amplicon with a size of 151 base pairs (bp), and only a single band was formed. Furthermore, the primer design results and the optimum temperature obtained will be used to develop a sensitive and specific rapid detection method of C. sakazakii in food samples using real-time PCR.

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The potential of the ToxR gene as a detection tool for vibrio parahaemolyticus in seafood

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AIP Conference Proceedings 2024年第1期2982卷

作者： M. Nurjayadi I. Krisdawati J. L. Declan G. I. Putri D. A. Juliansyah M. Azzahra I. Maulana A. M. A. Putri I. R. Kartika F. Kurniadewi D. Sukmawati S. Rahayu V. Saamia D. A. O. Saputro I. M. Wiranatha H. E. Enshay Department of Chemistry Faculty of Mathematics and Natural Science Universitas Negeri Jakarta Gedung KH. Hasjim Asj'ari 6th Floor Jl. Rawamangun Muka Jakarta Timur 13220 Indonesia Research Center for Detection of Pathogenic Bacteria Lembaga Penelitian dan Pengabdian Kepada Masyarakat Universitas Negeri Jakarta Jl. Rawamangun Muka Jakarta Timur 13220 Indonesia Department of Biology Faculty of Mathematics and Natural Science Universitas Negeri Jakarta Building KH. Hasjim Asj'ari 9th Floor Rawamangun Muka Street East Jakarta 13220 Indonesia. Center Forensic Laboratory of the Criminal Investigation Police of the Republic of Indonesia Ciapmbuan Babakan Madang Bogor 1681 Indonesia Institute of Bioproduct Development Universiti Teknologi Malaysia (UTM) Skudai Johor Barhru Malaysia. School of Chemical and Energy Engineering Faculty of Engineering Universiti Teknologi Malaysia (UTM) Skudai Johor Bharu Malaysia. City of Scientific Research and Technology Applications New Burg Al Arab Alexandria Egypt.

Vibrio parahaemolyticus must be detected quickly and precisely. This study uses the Gradient Polymerase Chain Reaction (PCR) method to evaluate the primer that can produce an amplicon at the ideal temperature for the Vibrio parahaemolyticus ToxR gene. The ToxR primer pair could amplify Vibrio parahaemolyticus ToxR fragments to form an amplicon with size 171 base pairs, according to the in-silico analysis conducted for the primer design. Gradient PCR was used to assess the primer's suitability for the design outcome and determine the ideal temperature to generate amplicons of the appropriate size with temperatures ranging from 53 to 62°C. The purity (A260/280) of the Vibrio parahaemolyticus isolate used as a template is 1.92, and its concentration is 51 ng/µl. The study's findings kindly reveal that annealing temperatures of 58°C produce the best outcomes for the ToxR primer, which results in the formation of a clear DNA band with a thickness band intensity and a size of 171 base pairs. Additionally, the primers and ideal temperatures discovered were utilized for the Real-Time PCR stage in creating sensitive, targeted, and quicker tools for detecting Vibrio parahaemolyticus in Seafood.

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Structural mechanical simulation to optimize the sensor arm geometry to be implemented on cranial remodeling orthosis

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AIP Conference Proceedings 2022年第1期2425卷

作者： F. Veloso D. Miranda Pedro Morais Helena R. Torres Roberto Laranjeira Mario Ruediger F. Miranda António C. M. Pinho J. L. Vilaça 3Department for Neonatology and Pediatric Intensive Care Children’s Hospital Medical Faculty of TU Dresden Germany 4Instituto Politécnico de Viana do Castelo Rua Escola Industrial e Comercial de Nun’Álvares 4900-347 Viana do Castelo Portugal 12Ai – School of Technology IPCA Barcelos Portugal 2CeNTI - Centre for Nanotechnology and Smart Materials Vila Nova de Famalicão Portugal 5Center for Research and Development in Mathematics and Applications (CIDMA) Department of Mathematics University of Aveiro 3810-193 Aveiro Portugal 6PROMETHEUS Instituto Politécnico de Viana do Castelo Rua Escola Industrial e Comercial de Nun’Álvares 4900-347 Viana do Castelo Portugal 7Department of Mechanical Engineering School of Engineering University of Minho Guimarães Portugal

For the treatment of moderate and severe cases of deformational plagiocephaly, an asymmetrical deformation of the skull, a cranial remodeling orthosis (CRO) is used. For the development of a new CRO concept, a pressure sensor grid is placed inside the orthosis that will allow the monitoring of excessive pressures and incorrect CRO positioning throughout the treatment. To implement the sensor grid in the CRO, high mobility of the sensor arms structure that joins the several sensors of this grid is required, however, it is intended that this procedure does not damage the printed copper tracks on the sensor structure. In this study, computer simulations were performed to optimize the sensor arm structure geometry, minimizing undesirable mechanical behavior in the sensor structure when subjected to tensile forces and displacements applied during its placement in the CRO. It was observed that the different sensor arm structures geometries have different effects on the mechanical behavior of the sensor structure when subjected to tensile forces and tensile displacement. The zigzag curve geometry presents the best performance based on high mobility without intense strain on the structure that could damage the printed copper tracks.

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GW190521 as a Merger of Proca Stars: A Potential New Vector Boson of 8.7×10−13 eV

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Physical Review Letters 2021年第8期126卷 081101-081101页

作者： Juan Calderón Bustillo Nicolas Sanchis-Gual Alejandro Torres-Forné José A. Font Avi Vajpeyi Rory Smith Carlos Herdeiro Eugen Radu Samson H. W. Leong Instituto Galego de Física de Altas Enerxías Universidade de Santiago de Compostela 15782 Santiago de Compostela Galicia Spain Department of Physics The Chinese University of Hong Kong Shatin N.T. Hong Kong Monash Centre for Astrophysics School of Physics and Astronomy Monash University Victoria 3800 Australia OzGrav: The ARC Centre of Excellence for Gravitational-Wave Discovery Clayton Victoria 3800 Australia Centro de Astrofísica e Gravitação—CENTRA Departamento de Física Instituto Superior Técnico—IST Universidade de Lisboa—UL Avenida Rovisco Pais 1 1049-001 Portugal Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA) Campus de Santiago 3810-183 Aveiro Portugal Max Planck Institute for Gravitational Physics (Albert Einstein Institute) Am Mühlenberg 1 Potsdam 14476 Germany Departamento de Astronomía y Astrofísica Universitat de València Dr. Moliner 50 46100 Burjassot (València) Spain Observatori Astronòmic Universitat de València C/ Catedrático José Beltrán 2 46980 Paterna (València) Spain

Advanced LIGO-Virgo have reported a short gravitational-wave signal (GW190521) interpreted as a quasicircular merger of black holes, one at least populating the pair-instability supernova gap, that formed a remnant black hole of Mf∼142 M⊙ at a luminosity distance of dL∼5.3 Gpc. With barely visible pre-merger emission, however, GW190521 merits further investigation of the pre-merger dynamics and even of the very nature of the colliding objects. We show that GW190521 is consistent with numerically simulated signals from head-on collisions of two (equal mass and spin) horizonless vector boson stars (aka Proca stars), forming a final black hole with Mf=231−17+13 M⊙, located at a distance of dL=571−181+348 Mpc. This provides the first demonstration of close degeneracy between these two theoretical models, for a real gravitational-wave event. The favored mass for the ultralight vector boson constituent of the Proca stars is μV=8.72−0.82+0.73×10−13 eV. Confirmation of the Proca star interpretation, which we find statistically slightly preferred, would provide the first evidence for a long sought dark matter particle.

关键词： Dark matter General relativity Gravitational waves Particle dark matter

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Lagrangian lie subalgebroids generating dy-namics for second-order mechanical systems on lie algebroids

arXiv

引用

arXiv 2018年

作者： Colombo, Leonardo Center for Research and Development in Mathematics and Applications Universidade de Aveiro Isca Aveiro3810-500 Portugal

The study of mechanical systems on Lie algebroids permits an understanding of the dynamics described by a Lagrangian or Hamiltonian function for a wide range of mechanical systems in a unified framework. Systems defined in tangent bundles, Lie algebras, principal bundles, reduced systems and constrained are included in such description. In this paper, we investigate how to derive the dynamics associated with a Lagrangian system defined on the set of admissible elements of a given Lie algebroid using Tulczyjew's triple on Lie algebroids and constructing a Lagrangian Lie subalgebroid of a symplectic Lie algebroid, by building on the geometric formalism for mechanics on Lie algebroids developed by M. de León, J.C. Marrero and E. Martínez on "Lagrangian submanifolds and dynamics on Lie algebroids".53D12, 70H50, 53D17 (Primary), 70H03, 37J15, 53D05 (Secondary) Copyright © 2018, The Authors. All rights reserved.

关键词： Lagrange multipliers

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