title string | abstract string | url string | arxiv_id string | date string | category string |
|---|---|---|---|---|---|
$20'$ Five-Point Function from $AdS_5\times S^5$ Supergravity | We develop new techniques to compute five-point correlation functions from
IIB supergravity on $AdS_5\times S^5$. Our methods rely entirely on symmetry
and general consistency conditions, and eschew detailed knowledge of the
supergravity effective action. We demonstrate our methods by computing the
five-point function ... | http://arxiv.org/abs/1906.05305v2 | 1906.05305 | 2019-10-21 | cybersecurity |
20-fold Accelerated 7T fMRI Using Referenceless Self-Supervised Deep Learning Reconstruction | High spatial and temporal resolution across the whole brain is essential to accurately resolve neural activities in fMRI. Therefore, accelerated imaging techniques target improved coverage with high spatio-temporal resolution. Simultaneous multi-slice (SMS) imaging combined with in-plane acceleration are used in large ... | https://arxiv.org/abs/2105.05827v1 | 2105.05827 | 2021-05-12 | cybersecurity |
20 GHz fiber-integrated femtosecond pulse and supercontinuum generation with a resonant electro-optic frequency comb | Frequency combs with mode spacing in the range of 10 to 20 gigahertz (GHz) are critical for increasingly important applications such as astronomical spectrograph calibration, high-speed dual-comb spectroscopy, and low-noise microwave generation. While electro-optic modulators and microresonators can provide narrowband ... | https://arxiv.org/abs/2303.11523v1 | 2303.11523 | 2023-03-21 | cybersecurity |
20 GHZ Low Noise LLRF System | A 20 GHz LLRF system is being built using a two-board(RF Front End +
ADC/DAC/FPGA) architecture. The RF Front End provides 8 down-converting
channels and 3 up-converting channels (5.5-20 GHz RF to 0.05-3 GHz IF).
Separate, phase locked, low-noise input and output LO's are generated on-board
with an independent programm... | http://arxiv.org/abs/1910.11936v1 | 1910.11936 | 2019-10-23 | cybersecurity |
20 K superconductivity in heavily electron doped surface layer of FeSe bulk crystal | A superconducting transition temperature Tc as high as 100 K was recently
discovered in 1 monolayer (1ML) FeSe grown on SrTiO3 (STO). The discovery
immediately ignited efforts to identify the mechanism for the dramatically
enhanced Tc from its bulk value of 7 K. Currently, there are two main views on
the origin of the ... | http://arxiv.org/abs/1511.07950v2 | 1511.07950 | 2015-12-15 | cybersecurity |
20-MAD -- 20 Years of Issues and Commits of Mozilla and Apache Development | Data of long-lived and high profile projects is valuable for research on
successful software engineering in the wild. Having a dataset with different
linked software repositories of such projects, enables deeper diving
investigations. This paper presents 20-MAD, a dataset linking the commit and
issue data of Mozilla an... | http://arxiv.org/abs/2003.14015v1 | 2003.14015 | 2020-03-31 | cybersecurity |
20min-XD: A Comparable Corpus of Swiss News Articles | We present 20min-XD (20 Minuten cross-lingual document-level), a French-German, document-level comparable corpus of news articles, sourced from the Swiss online news outlet 20 Minuten/20 minutes. Our dataset comprises around 15,000 article pairs spanning 2015 to 2024, automatically aligned based on semantic similarity.... | https://arxiv.org/abs/2504.21677v1 | 2504.21677 | 2025-04-30 | cybersecurity |
20-Mode Universal Quantum Photonic Processor | Integrated photonics is an essential technology for optical quantum computing. Universal, phase-stable, reconfigurable multimode interferometers (quantum photonic processors) enable manipulation of photonic quantum states and are one of the main components of photonic quantum computers in various architectures. In this... | https://arxiv.org/abs/2203.01801v5 | 2203.01801 | 2022-03-03 | cybersecurity |
20 open questions about deformations of compactifiable manifolds | Deformation theory of complex manifolds is a classical subject with recent
new advances in the noncompact case using both algebraic and analytic methods.
In this note, we recall some concepts of the existing theory and introduce
new notions of deformations for manifolds with boundary, for compactifiable
manifolds, an... | http://arxiv.org/abs/2004.11299v1 | 2004.11299 | 2020-04-23 | cybersecurity |
20 ps Time Resolution with a Fully-Efficient Monolithic Silicon Pixel Detector without Internal Gain Layer | A second monolithic silicon pixel prototype was produced for the MONOLITH project. The ASIC contains a matrix of hexagonal pixels with 100 {\mu}m pitch, readout by a low-noise and very fast SiGe HBT frontend electronics. Wafers with 50 {\mu}m thick epilayer of 350 {\Omega}cm resistivity were used to produce a fully dep... | https://arxiv.org/abs/2301.12244v1 | 2301.12244 | 2023-01-28 | cybersecurity |
20 T Dipole Magnet Based on Hybrid HTS/LTS Cos-Theta Coils with Stress Management | This paper presents the design concept of the dipole magnet with 50 mm aperture, 20 T nominal field and 13% margin based on a six-layer cos-theta (CT) hybrid coil design. Due to the high stresses and strains in the coil at high field, Stress Management (SM) elements are implemented in the CT coil geometry. The results ... | https://arxiv.org/abs/2305.06776v1 | 2305.06776 | 2023-05-11 | cybersecurity |
(2,0) theory on $S^5 \times S^1$ and quantum M2 branes | The superconformal index $Z$ of the 6d (2,0) theory on $S^5 \times S^1$ (which is related to the localization partition function of 5d SYM on $S^5$) should be captured at large $N$ by the quantum M2 brane theory in the dual M-theory background. Generalizing the type IIA string theory limit of this relation discussed in... | https://arxiv.org/abs/2309.10786v4 | 2309.10786 | 2023-09-19 | cybersecurity |
20 Years of ACE Data: How Superposed Epoch Analyses Reveal Generic Features in Interplanetary CME Profiles | Interplanetary coronal mass ejections (ICMEs) are magnetic structures
propagating from the Sun's corona to the interplanetary medium. With over 20
years of observations at the L1 libration point, ACE offers hundreds of ICMEs
detected at different times during several solar cycles and with different
features such as the... | http://arxiv.org/abs/2011.05050v1 | 2011.05050 | 2020-11-10 | cybersecurity |
20 Years of DDoS: a Call to Action | Botnet Distributed Denial of Service (DDoS) attacks are now 20 years old;
what has changed in that time? Their disruptive presence, their volume,
distribution across the globe, and the relative ease of launching them have all
been trending in favor of attackers. Our increases in network capacity and our
architectural d... | http://arxiv.org/abs/1904.02739v2 | 1904.02739 | 2019-04-21 | cybersecurity |
20 years of developments in optical frequency comb technology and applications | Optical frequency combs were developed nearly two decades ago to support the
world's most precise atomic clocks. Acting as precision optical synthesizers,
frequency combs enable the precise transfer of phase and frequency information
from a high-stability reference to hundreds of thousands of tones in the
optical domai... | http://arxiv.org/abs/1909.05384v1 | 1909.05384 | 2019-09-11 | cybersecurity |
20 years of disk winds in 4U 1630-47 -- I. Long-term behavior and influence of hard X-rays | Highly ionized X-ray wind signatures have been found in the soft states of high-inclination Black Hole Low Mass X-ray Binaries (BHLMXBs) for more than two decades. Yet signs of a systematic evolution of the outflow itself along the outburst remain elusive, due to the limited sampling of individual sources and the neces... | https://arxiv.org/abs/2504.00991v1 | 2504.00991 | 2025-04-01 | cybersecurity |
20 Years of Evolution from Cognitive to Intelligent Communications | It has been 20 years since the concept of cognitive radio (CR) was proposed,
which is an efficient approach to provide more access opportunities to connect
massive wireless devices. To improve the spectrum efficiency, CR enables
unlicensed usage of licensed spectrum resources. It has been regarded as the
key enabler fo... | http://arxiv.org/abs/1909.11562v1 | 1909.11562 | 2019-09-25 | cybersecurity |
20 years of Greedy Randomized Adaptive Search Procedures with Path Relinking | This is a comprehensive review of the Greedy Randomized Adaptive Search Procedure (GRASP) metaheuristic and its hybridization with Path Relinking (PR) over the past two decades. GRASP with PR has become a widely adopted approach for solving hard optimization problems since its proposal in 1999. The paper covers the his... | https://arxiv.org/abs/2312.12663v1 | 2312.12663 | 2023-12-19 | cybersecurity |
20 Years of Light Pentaquark Searches | In this paper, I pay tribute to my exceptional colleagues and friends Dmitri Diakonov, Victor Petrov, and Maxim Polyakov by examining the experimental progress and current status of the searches of the $\Theta^+$ pentaquark from its inception to the present. | https://arxiv.org/abs/2503.21545v2 | 2503.21545 | 2025-03-27 | cybersecurity |
20 Years of Mobility Modeling & Prediction: Trends, Shortcomings & Perspectives | In this paper, we present a comprehensive survey of human-mobility modeling
based on 1680 articles published between 1999 and 2019, which can serve as a
roadmap for research and practice in this area. Mobility modeling research has
accelerated the advancement of several fields of studies such as urban
planning, epidemi... | http://arxiv.org/abs/1906.07451v1 | 1906.07451 | 2019-06-18 | cybersecurity |
20 years of network community detection | A fundamental technical challenge in the analysis of network data is the automated discovery of communities - groups of nodes that are strongly connected or that share similar features or roles. In this commentary we review progress in the field over the last 20 years. | https://arxiv.org/abs/2208.00111v2 | 2208.00111 | 2022-07-30 | cybersecurity |
20 years of ordinal patterns: Perspectives and challenges | In 2002, in a seminal article, Christoph Bandt and Bernd Pompe proposed a new methodology for the analysis of complex time series, now known as Ordinal Analysis. The ordinal methodology is based on the computation of symbols (known as ordinal patterns) which are defined in terms of the temporal ordering of data points ... | https://arxiv.org/abs/2204.12883v1 | 2204.12883 | 2022-04-27 | cybersecurity |
20 years of photometric microlensing events predicted by Gaia DR2: Potential planet-hosting lenses within 100 pc | Context. Gaia DR2 offers unparalleled precision on stars' parallaxes and
proper motions. This allows the prediction of microlensing events for which the
lens stars (and any planets they possess) are nearby and may be well studied
and characterised. Aims. We identify a number of potential microlensing events
that will o... | http://arxiv.org/abs/1805.11638v2 | 1805.11638 | 2018-07-10 | cybersecurity |
$^{210}$Pb measurements at the André E. Lalonde AMS Laboratory for the radioassay of materials used in rare event search detectors | Naturally occurring radionuclide $^{210}$Pb ($T_{1/2}$=22.2 y) is an important source of background in rare event searches, such as neutrinoless double-$\beta$ decay and dark matter direct detection experiments. When a sample mass of hundreds of grams is available, $\gamma$-counting measurements can be performed. Howev... | https://arxiv.org/abs/2102.06776v2 | 2102.06776 | 2021-02-15 | cybersecurity |
$2^{1296}$ Exponentially Complex Quantum Many-Body Simulation via Scalable Deep Learning Method | For decades, people are developing efficient numerical methods for solving the challenging quantum many-body problem, whose Hilbert space grows exponentially with the size of the problem. However, this journey is far from over, as previous methods all have serious limitations. The recently developed deep learning metho... | https://arxiv.org/abs/2204.07816v1 | 2204.07816 | 2022-04-16 | cybersecurity |
2-16 GHz Multifrequency X-Cut Lithium Niobate NEMS Resonators on a Single Chip | This work presents the design, fabrication, and testing of X-Cut Lithium Niobate (LN) acoustic nanoelectromechanical (NEMS) Laterally Vibrating Resonators (LVRs) and Degenerate LVRs (d-LVRs) operating in the S0 (YZ30) and SH0 (YZ-10) modes between 2 to 16 GHz range, monolithically fabricated on a single chip. The NEMS ... | https://arxiv.org/abs/2405.05547v1 | 2405.05547 | 2024-05-09 | cybersecurity |
(216) Kleopatra, a low density critically rotating M-type asteroid | Context. The recent estimates of the 3D shape of the M/Xe-type triple asteroid system (216) Kleopatra indicated a density of 5 g.cm$^{-3}$. Such a high density implies a high metal content and a low porosity which is not easy to reconcile with its peculiar dumbbell shape. Aims. Given the unprecedented angular resolutio... | https://arxiv.org/abs/2108.07207v1 | 2108.07207 | 2021-08-16 | cybersecurity |
21 Balmer Jump Street: The Nebular Continuum at High Redshift and Implications for the Bright Galaxy Problem, UV Continuum Slopes, and Early Stellar Populations | We study, from both a theoretical and observational perspective, the physical origin and spectroscopic impact of extreme nebular emission in high-redshift galaxies. The nebular continuum, which can appear during extreme starbursts, is of particular importance as it tends to redden UV slopes and has a significant contri... | https://arxiv.org/abs/2408.03189v2 | 2408.03189 | 2024-08-06 | cybersecurity |
21-cm Constraints on Dark Matter Annihilation after an Early Matter-Dominated Era | Although it is commonly assumed that relativistic particles dominate the energy density of the universe quickly after inflation, a variety of well-motivated scenarios predict an early matter-dominated era (EMDE) before the onset of Big Bang nucleosynthesis. Subhorizon dark matter density perturbations grow faster durin... | https://arxiv.org/abs/2502.08719v1 | 2502.08719 | 2025-02-12 | cybersecurity |
21-cm constraints on spinning primordial black holes | Hawking radiation from primordial black holes (PBH) can ionize and heat up neutral gas during the cosmic dark ages, leaving imprints on the global 21-cm signal of neutral hydrogen. We use the global 21-cm signal to constrain the abundance of spinning PBHs in mass range of $[2 \times 10^{13}, 10^{18}]$ grams. We conside... | https://arxiv.org/abs/2108.13256v2 | 2108.13256 | 2021-08-30 | cybersecurity |
21 cm cosmology and spin temperature reduction via spin-dependent dark matter interactions | The EDGES low-band experiment has measured an absorption feature in the cosmic microwave background radiation (CMB), corresponding to the 21 cm hyperfine transition of hydrogen at redshift $z \simeq 17$, before the era of cosmic reionization. The amplitude of this absorption is connected to the ratio of singlet and tri... | https://arxiv.org/abs/1902.09552v2 | 1902.09552 | 2019-02-25 | cybersecurity |
21cmEMU: an emulator of 21cmFAST summary observables | Recent years have witnessed rapid progress in observations of the Epoch of Reionization (EoR). These have enabled high-dimensional inference of galaxy and intergalactic medium (IGM) properties during the first billion years of our Universe. However, even using efficient, semi-numerical simulations, traditional inferenc... | https://arxiv.org/abs/2309.05697v3 | 2309.05697 | 2023-09-11 | cybersecurity |
21cm Epoch of Reionisation Power Spectrum with Closure Phase using the Murchison Widefield Array | The radio interferometric closure phases can be a valuable tool for studying cosmological {H\scriptsize{I}}~from the early Universe. Closure phases have the advantage of being immune to element-based gains and associated calibration errors. Thus, calibration and errors therein, which are often sources of systematics li... | https://arxiv.org/abs/2409.02906v1 | 2409.02906 | 2024-09-04 | cybersecurity |
21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal | We introduce a powerful semi-numeric modeling tool, 21cmFAST, designed to
efficiently simulate the cosmological 21-cm signal. Our code generates 3D
realizations of evolved density, ionization, peculiar velocity, and spin
temperature fields, which it then combines to compute the 21-cm brightness
temperature. Although th... | http://arxiv.org/abs/1003.3878v1 | 1003.3878 | 2010-03-19 | cybersecurity |
21cmFAST v3: A Python-integrated C code forgenerating 3D realizations of the cosmic 21cm signal | This brief code paper presents a new Python-wrapped version of the popular
21cm cosmology simulator, 21cmFAST. The new version, v3+, maintains the same
core functionality of previous versions of 21cmFAST, but features a simple and
intuitive interface, and a great deal more flexibility. This evolution
represents the wor... | http://arxiv.org/abs/2010.15121v1 | 2010.15121 | 2020-10-28 | cybersecurity |
21cmFirstCLASS I. Cosmological tool for $Λ$CDM and beyond | In this work we present 21cmFirstCLASS, a modified version of 21cmFAST, the most popular code in the literature for computing the anisotropies of the 21-cm signal. Our code uses the public cosmic microwave background (CMB) Boltzmann code CLASS, to establish consistent initial conditions at recombination for any set of ... | https://arxiv.org/abs/2309.03942v4 | 2309.03942 | 2023-09-07 | cybersecurity |
21cmFirstCLASS II. Early linear fluctuations of the 21cm signal | In a companion paper we introduce 21cmFirstCLASS, a new code for computing the 21-cm anisotropies, assembled from the merger of the two popular codes 21cmFAST and CLASS. Unlike the standard 21cmFAST, which begins at $z=35$ with homogeneous temperature and ionization boxes, our code begins its calculations from recombin... | https://arxiv.org/abs/2309.03948v3 | 2309.03948 | 2023-09-07 | cybersecurity |
21cmfish: Fisher-matrix framework for fast parameter forecasts from the cosmic 21-cm signal | The 21-cm signal from neutral hydrogen in the early universe will provide unprecedented information about the first stars and galaxies. Extracting this information, however, requires accounting for many unknown astrophysical processes. Semi-numerical simulations are key for exploring the vast parameter space of said pr... | https://arxiv.org/abs/2212.09797v2 | 2212.09797 | 2022-12-19 | cybersecurity |
21-cm fluctuations from primordial magnetic fields | The fluid forces associated with primordial magnetic fields (PMFs) generate small-scale fluctuations in the primordial density field, which add to the $\mathrm{\Lambda CDM}$ linear matter power spectrum on small scales. These enhanced small-scale fluctuations lead to earlier formation of galactic halos and stars and th... | https://arxiv.org/abs/2308.04483v2 | 2308.04483 | 2023-08-08 | cybersecurity |
21-cm foreground removal using AI and frequency-difference technique | The deep learning technique has been employed in removing foreground contaminants from 21 cm intensity mapping, but its effectiveness is limited by the large dynamic range of the foreground amplitude. In this study, we develop a novel foreground removal technique grounded in U-Net networks. The essence of this techniqu... | https://arxiv.org/abs/2310.06518v2 | 2310.06518 | 2023-10-10 | cybersecurity |
21cm foregrounds and polarization leakage: a user's guide on cleaning and mitigation strategies | The success of HI intensity mapping is largely dependent on how well 21cm foreground contamination can be controlled. In order to progress our understanding further, we present a range of simulated foreground data from four different $\sim3000$\,deg$^2$ sky regions, with and without effects from polarization leakage. C... | https://arxiv.org/abs/2010.02907v2 | 2010.02907 | 2020-10-06 | cybersecurity |
21 cm Forest Constraints on Primordial Black Holes | Primordial black holes (PBHs) as part of the Dark Matter (DM) would modify the evolution of large-scale structures and the thermal history of the universe. Future 21 cm forest observations, sensitive to small scales and the thermal state of the Inter Galactic Medium (IGM), could probe the existence of such PBHs. In thi... | https://arxiv.org/abs/2104.10695v1 | 2104.10695 | 2021-04-21 | cybersecurity |
21cm forest probes on the axion dark matter in the post-inflationary Peccei-Quinn symmetry breaking scenarios | We study the future prospects of the 21cm forest observations on the
axion-like dark matter when the spontaneous breaking of the global Peccei-Quinn
(PQ) symmetry occurs after the inflation. The large isocurvature perturbations
of order unity sourced from axion-like particles can result in the enhancement
of minihalo f... | http://arxiv.org/abs/2005.05589v3 | 2005.05589 | 2020-07-14 | cybersecurity |
21cm Forest with the SKA | An alternative to both the tomography technique and the power spectrum
approach is to search for the 21cm forest, that is the 21cm absorption features
against high-z radio loud sources caused by the intervening cold neutral
intergalactic medium (IGM) and collapsed structures. Although the existence of
high-z radio loud... | http://arxiv.org/abs/1501.04425v1 | 1501.04425 | 2015-01-19 | cybersecurity |
21cm Global Signal Extraction: Extracting the 21cm Global Signal using Artificial Neural Networks | The study of the cosmic Dark Ages, Cosmic Dawn, and Epoch of Reionization (EoR) using the all-sky averaged redshifted HI 21cm signal, are some of the key science goals of most of the ongoing or upcoming experiments, for example, EDGES, SARAS, and the SKA. This signal can be detected by averaging over the entire sky, us... | https://arxiv.org/abs/1911.02580v1 | 1911.02580 | 2019-11-06 | cybersecurity |
21cm Intensity Mapping cross-correlation with galaxy surveys: current and forecasted cosmological parameters estimation for the SKAO | We present a comprehensive set of forecasts for the cross-correlation signal between 21cm intensity mapping and galaxy redshift surveys. We focus on the data sets that will be provided by the SKAO for the 21cm signal, DESI and Euclid for galaxy clustering. We build a likelihood which takes into account the effect of th... | https://arxiv.org/abs/2309.00710v2 | 2309.00710 | 2023-09-01 | cybersecurity |
21 cm Intensity Mapping with the DSA-2000 | Line intensity mapping is a promising probe of the universe's large-scale structure. We explore the sensitivity of the DSA-2000, a forthcoming array consisting of over 2000 dishes, to the statistical power spectrum of neutral hydrogen's 21 cm emission line. These measurements would reveal the distribution of neutral hy... | https://arxiv.org/abs/2311.00896v2 | 2311.00896 | 2023-11-01 | cybersecurity |
21cm Limits on Decaying Dark Matter and Primordial Black Holes | Recently the Experiment to Detect the Global Epoch of Reionization Signature
(EDGES) reported the detection of a 21cm absorption signal stronger than
astrophysical expectations. In this paper we study the impact of radiation from
dark matter (DM) decay and primordial black holes (PBH) on the 21cm radiation
temperature ... | http://arxiv.org/abs/1803.09390v1 | 1803.09390 | 2018-03-26 | cybersecurity |
21-cm line Anomaly: A brief Status | In this short review I present the status of the global 21-cm signal detected
by EDGES in March 2018. It is organized in three parts. First, I present the
EDGES experiment and the fitting procedure used by the collaboration to extract
the tiny 21-cm signal from large foregrounds of galactic synchrotron emission.
Then, ... | http://arxiv.org/abs/1907.13384v2 | 1907.13384 | 2019-09-13 | cybersecurity |
21 cm Line Astronomy and Constraining New Physics | The 21 cm signal appears to be a treasure trove to provide an insight into the period when the first generation of luminous objects formed in the Universe. Hydrogen is the predominating fraction of the total baryonic matter during cosmic dawn (CD). Therefore, it is convenient and advantageous to study physics during CD... | https://arxiv.org/abs/2301.02655v1 | 2301.02655 | 2023-01-06 | cybersecurity |
21 cm line signal from magnetic modes | The Lorentz term raises the linear matter power on small scale which leads to
interesting signatures in the 21 cm signal. Numerical simulations of the
resuting nonlinear density field, the distribution of ionized hydrogen and the
21 cm signal at different values of redshift are presented for magnetic fields
with field ... | http://arxiv.org/abs/1805.10943v1 | 1805.10943 | 2018-05-28 | cybersecurity |
21CMMC: an MCMC analysis tool enabling astrophysical parameter studies of the cosmic 21 cm signal | We introduce 21CMMC: a parallelized, Monte Carlo Markov Chain analysis tool,
incorporating the epoch of reionization (EoR) seminumerical simulation
21CMFAST. 21CMMC estimates astrophysical parameter constraints from 21 cm EoR
experiments, accommodating a variety of EoR models, as well as priors on model
parameters and ... | http://arxiv.org/abs/1501.06576v2 | 1501.06576 | 2015-01-26 | cybersecurity |
21CMMC with a 3D light-cone: the impact of the co-evolution approximation on the astrophysics of reionisation and cosmic dawn | We extend 21CMMC, a Monte Carlo Markov Chain sampler of 3D reionisation
simulations, to perform parameter estimation directly on 3D light-cones of the
cosmic 21cm signal. This brings theoretical analysis closer to the tomographic
21-cm observations achievable with next generation interferometers like HERA
and the SKA. ... | http://arxiv.org/abs/1801.01592v1 | 1801.01592 | 2018-01-05 | cybersecurity |
21-cm observations and warm dark matter models | Observations of the redshifted 21-cm signal (in absorption or emission) allow
us to peek into the epoch of "dark ages" and the onset of reionization. These
data can provide a novel way to learn about the nature of dark matter, in
particular about the formation of small size dark matter halos. However, the
connection be... | http://arxiv.org/abs/1904.03097v2 | 1904.03097 | 2019-12-10 | cybersecurity |
21 cm observations: calibration, strategies, observables | This chapter aims to provide a review of the basics of 21 cm interferometric
observations and its methodologies. A summary of the main concepts of radio
interferometry and their connection with the 21 cm observables - power spectra
and images - is presented. I then provide a review of interferometric
calibration and it... | http://arxiv.org/abs/1909.11938v1 | 1909.11938 | 2019-09-26 | cybersecurity |
21-cm power spectrum and ionization bias as a probe of long-mode modulated non Gaussian sky | The observed hemispherical power asymmetry in cosmic microwave background
radiation can be explained by long wavelength mode (long-mode) modulation. In
this work we study the prospect of the detection of this effect in the angular
power spectrum of 21-cm brightness temperature. For this task, we study the
effect of the... | http://arxiv.org/abs/1812.11150v3 | 1812.11150 | 2019-08-15 | cybersecurity |
21 cm Power Spectrum for Bimetric Gravity and its Detectability with SKA1-Mid Telescope | We consider a modified gravity theory through a special kind of ghost-free bimetric gravity, where one massive spin-2 field interacts with a massless spin-2 field. In this bimetric gravity, the late time cosmic acceleration is achievable. Alongside the background expansion of the Universe, we also study the first-order... | https://arxiv.org/abs/2306.03875v1 | 2306.03875 | 2023-06-06 | cybersecurity |
21 cm power spectrum in interacting cubic Galileon model | We show the detectability of interacting and non-interacting cubic Galileon models from the $\Lambda$CDM model through the 21 cm power spectrum. We show that the interferometric observations like the upcoming SKA1-mid can detect both the interacting and the non-interacting cubic Galileon model from the $\Lambda$CDM mod... | https://arxiv.org/abs/2208.11560v1 | 2208.11560 | 2022-08-24 | cybersecurity |
21cmSense v2: A modular, open-source 21cm sensitivity calculator | The 21cm line of neutral hydrogen is a powerful probe of the high-redshift universe (Cosmic Dawn and the Epoch of Reionization), with an unprecedented potential to inform us about key processes of early galaxy formation, the first stars and even cosmology and structure formation, via intensity mapping. It is the subjec... | https://arxiv.org/abs/2406.02415v1 | 2406.02415 | 2024-06-04 | cybersecurity |
21-cm signal from cosmic dawn - II: Imprints of the light-cone effects | Details of various unknown physical processes during the cosmic dawn and the
epoch of reionization can be extracted from observations of the redshifted
21-cm signal. These observations, however, will be affected by the evolution of
the signal along the line-of-sight which is known as the "light-cone effect".
We model t... | http://arxiv.org/abs/1504.05601v2 | 1504.05601 | 2015-08-12 | cybersecurity |
21cm signal from Dark Ages collapsing halos with detailed molecular cooling treatment | Context. In order to understand the formation of the first stars, which set the transition between the Dark Ages and Cosmic Dawn epochs, it is necessary to provide a detailed description of the physics at work within the first clouds of gas which, during their gravitational collapse, will set the conditions for stars t... | https://arxiv.org/abs/2404.08479v1 | 2404.08479 | 2024-04-12 | cybersecurity |
21-cm Signal from the Epoch of Reionization: A Machine Learning upgrade to Foreground Removal with Gaussian Process Regression | In recent years, a Gaussian Process Regression (GPR) based framework has been developed for foreground mitigation from data collected by the LOw-Frequency ARray (LOFAR), to measure the 21-cm signal power spectrum from the Epoch of Reionization (EoR) and Cosmic Dawn. However, it has been noted that through this method t... | https://arxiv.org/abs/2311.16633v2 | 2311.16633 | 2023-11-28 | cybersecurity |
21cm signal predictions at Cosmic Dawn and Reionization with coupled radiative-hydrodynamics | The process of heating and reionization of the Universe at high redshift links small scale structures/galaxy formation and large scale inter-galactic medium properties. Even if the first one is difficult to observe, an observation window is opening on the second one, with the promising development of current and future... | https://arxiv.org/abs/2103.03061v1 | 2103.03061 | 2021-03-04 | cybersecurity |
21cm Signal Recovery via the Robust Principle Component Analysis | The redshifted 21~cm signal from neutral hydrogen (HI) is potentially a very
powerful probe for cosmology, but a difficulty in its observation is that it is
much weaker than foreground radiation from the Milky Way as well as
extragalactic radio sources. The foreground radiation at different frequencies
are however cohe... | http://arxiv.org/abs/1801.04082v1 | 1801.04082 | 2018-01-12 | cybersecurity |
21cm signal sensitivity to dark matter decay | The redshifted 21cm signal from the Cosmic Dawn is expected to provide unprecedented insights into early Universe astrophysics and cosmology. Here we explore how dark matter can heat the intergalactic medium before the first galaxies, leaving a distinctive imprint in the 21cm power spectrum. We provide the first dedica... | https://arxiv.org/abs/2308.16656v2 | 2308.16656 | 2023-08-31 | cybersecurity |
21-cm signature of the first sources in the Universe: Prospects of detection with SKA | Currently several low-frequency experiments are being planned to study the
nature of the first stars using the redshifted 21-cm signal from the cosmic
dawn and epoch of reionization. Using a one-dimensional radiative transfer
code, we model the 21-cm signal pattern around the early sources for different
source models, ... | http://arxiv.org/abs/1511.07448v2 | 1511.07448 | 2016-05-12 | cybersecurity |
21-cm signatures of residual HI inside cosmic HII regions during reionization | We investigate the impact of sinks of ionizing radiation on the
reionization-era 21-cm signal, focusing on 1-point statistics. We consider
sinks in both the intergalactic medium and inside galaxies. At a fixed filling
factor of HII regions, sinks will have two main effects on the 21-cm
morphology: (i) as inhomogeneous ... | http://arxiv.org/abs/1501.01970v2 | 1501.01970 | 2015-05-27 | cybersecurity |
21cmVAE: A Very Accurate Emulator of the 21-cm Global Signal | Considerable observational efforts are being dedicated to measuring the sky-averaged (global) 21-cm signal of neutral hydrogen from Cosmic Dawn and the Epoch of Reionization. Deriving observational constraints on the astrophysics of this era requires modeling tools that can quickly and accurately generate theoretical s... | https://arxiv.org/abs/2107.05581v4 | 2107.05581 | 2021-07-12 | cybersecurity |
21-Component Compositionally Complex Ceramics: Discovery of Ultrahigh-Entropy Weberite and Fergusonite Phases and a Pyrochlore-Weberite Transition | Two new high-entropy ceramics (HECs) in the weberite and fergusonite structures, along with unexpected formation of ordered pyrochlore phases with ultrahigh-entropy compositions and an abrupt pyrochlore-weberite transition, are discovered in a 21-component oxide system. While the Gibbs phase rule allows 21 equilibrium ... | https://arxiv.org/abs/2112.15381v2 | 2112.15381 | 2021-12-31 | cybersecurity |
2+1d Compact Lifshitz Theory, Tensor Gauge Theory, and Fractons | The 2+1d continuum Lifshitz theory of a free compact scalar field plays a prominent role in a variety of quantum systems in condensed matter physics and high energy physics. It is known that in compact space, it has an infinite ground state degeneracy. In order to understand this theory better, we consider two candidat... | https://arxiv.org/abs/2209.10030v2 | 2209.10030 | 2022-09-20 | cybersecurity |
2+1 d Georgi Glashow Model Near Critical Temperature | We study correlations functions of magnetic vortices $V$ and Polyakov loop
$P$ operators in the 2+1 dimensional Georgi-Glashow model in the vicinity of
the deconfining phase transition. In this regime the (dimensionally reduced)
model is mapped onto a free theory of two massive Majorana fermions. We utilize
this fermio... | http://arxiv.org/abs/1612.07267v2 | 1612.07267 | 2017-04-11 | cybersecurity |
$(2+1)$-dimensional AKNS($-N$) Systems: $ N=3,4$ | In this work we continue to study negative AKNS($N$) that is AKNS($-N$)
system for $N=3,4$. We obtain all possible local and nonlocal reductions of
these equations. We construct the Hirota bilinear forms of these equations and
find one-soliton solutions. From the reduction formulas we obtain also
one-soliton solutions ... | http://arxiv.org/abs/1910.11298v1 | 1910.11298 | 2019-10-24 | cybersecurity |
$(2+1)$-Dimensional Black Holes in $f(R,φ)$ Gravity | We consider a $f(R)$ gravity theory in $(2+1)$-dimensions with a self-interacting scalar field non-minimally coupled to gravity. Without specifying the form of the $f(R)$ function, solving the field equations we find that the Ricci scalar receives a non-linear correction term which breaks the conformal invariance and l... | https://arxiv.org/abs/2201.00035v2 | 2201.00035 | 2021-12-31 | cybersecurity |
(2+1)-dimensional Chern-Simons bi-gravity with AdS Lie bialgebra as an interacting theory of two massless spin-2 fields | We introduce a new Lie bialgebra structure for the anti de Sitter (AdS) Lie
algebra in (2+1)-dimensional spacetime. By gauging the resulting \textit{AdS
Lie bialgebra}, we write a Chern-Simons gauge theory of bi-gravity involving
two dreibeins rather than two metrics, which describes two interacting massless
spin-2 fie... | http://arxiv.org/abs/1706.02129v3 | 1706.02129 | 2018-08-27 | cybersecurity |
(2+1) dimensional cosmological models in f(R; T) gravity with $Λ$(R; T) | We intend to study a new class of cosmological models in $f(R, T)$ modified theories of gravity, hence define the cosmological constant $\Lambda$ as a function of the trace of the stress energy-momentum-tensor $T$ and the Ricci scalar $R$, and name such a model "$\Lambda(R, T)$ gravity" where we have specified a certai... | https://arxiv.org/abs/2003.11355v1 | 2003.11355 | 2020-03-19 | cybersecurity |
(2 +1)-dimensional Duffin-Kemmer-Petiau oscillator under a magnetic field in the presence of a minimal length in the noncommutative space | Using the momentum space representation, we study the (2 +1)-dimensional
Duffin-Kemmer-Petiau oscillator for spin 0 particle under a magnetic field in
the presence of a minimal length in the noncommutative space. The explicit form
of energy eigenvalues are found, the wave functions and the corresponding
probability den... | http://arxiv.org/abs/1706.04298v1 | 1706.04298 | 2017-06-14 | cybersecurity |
2+1 dimensional Fermions on the low-buckled honey-comb structured lattice plane and classical Casimir-Polder force | We have calculated the Casimir-Polder interaction (CPI) of a micro-particle
with a sheet on the basis of the Klimchitskaya-Mostepanenko theory. We find the
result that for non-trivial susceptibility values of the sheet and
micro-particle, there is crossover between attractive and repulsive behavior.
The transition depe... | http://arxiv.org/abs/1505.07036v3 | 1505.07036 | 2016-07-10 | cybersecurity |
$2+1$ dimensional Floquet systems and lattice fermions: Exact bulk spectral equivalence | A connection has recently been proposed between periodically driven systems known as Floquet insulators in continuous time and static fermion theories in discrete time. This connection has been established in a $(1+1)$-dimensional free theory, where an explicit mapping between the spectra of a Floquet insulator and a d... | https://arxiv.org/abs/2410.18226v2 | 2410.18226 | 2024-10-23 | cybersecurity |
(2+1)-dimensional f(R) gravity solutions via Hojman symmetry | In this paper, we use the Hojman symmetry approach to find new $(2+1)$-dimensional $f(R)$ gravity solutions, in comparison to Noether symmetry approach. In the special case of Hojman symmetry vector $X=R$, we recover $(2+1)$-dimensional BTZ black hole and generalized $(2+1)$-dimensional BTZ black hole solutions, obtain... | https://arxiv.org/abs/2010.08424v3 | 2010.08424 | 2020-10-16 | cybersecurity |
2+1 dimensional gravity | It gives me great pleasure to review some of the joint work by Tullio Regge
and myself. We worked intensely on 2+1-dimensional gravity from 1989 for about
five years, and published 16 articles. I will present and review two of our
early articles, highlighting what I believe are the most important results,
some of them ... | http://arxiv.org/abs/1804.08456v2 | 1804.08456 | 2018-04-24 | cybersecurity |
2+1-dimensional gravity coupled to a dust shell: quantization in terms of global phase space variables | We perform canonical analysis of a model in which gravity is coupled to a
spherically symmetric dust shell in 2+1 spacetime dimensions. The result is a
reduced action depending on a finite number of degrees of freedom. The emphasis
is made on finding canonical variables providing the global chart for the
entire phase s... | http://arxiv.org/abs/1812.11425v1 | 1812.11425 | 2018-12-29 | cybersecurity |
(2+1)-Dimensional Gravity in Weyl Integrable Spacetime | We investigate (2+1)-dimensional gravity in a Weyl integrable spacetime
(WIST). We show that, unlike general relativity, this scalar-tensor theory has
a Newtonian limit for any dimension and that in three dimensions the congruence
of world lines of particles of a pressureless fluid has a non-vanishing
geodesic deviatio... | http://arxiv.org/abs/1503.04186v1 | 1503.04186 | 2015-03-13 | cybersecurity |
(2+1)-dimensional interacting model of two massless spin-2 fields as a bi-gravity model | We propose a new group-theoretical (Chern-Simons) formulation for the
bi-metric theory of gravity in (2+1)-dimensional spacetime which describe two
interacting massless spin-2 fields. Our model has been formulated in terms of
two dreibeins rather than two metrics. We obtain our Chern-Simons gravity model
by gauging {\i... | http://arxiv.org/abs/1705.11042v4 | 1705.11042 | 2018-04-24 | cybersecurity |
(2+1)-dimensional interface dynamics: mixing time, hydrodynamic limit and Anisotropic KPZ growth | Stochastic interface dynamics serve as mathematical models for diverse
time-dependent physical phenomena: the evolution of boundaries between
thermodynamic phases, crystal growth, random deposition... Interesting limits
arise at large space-time scales: after suitable rescaling, the randomly
evolving interface converge... | http://arxiv.org/abs/1711.05571v1 | 1711.05571 | 2017-11-15 | cybersecurity |
(2+1)-dimensional KdV, fifth-order KdV, and Gardner equations derived from the ideal fluid model. Soliton, cnoidal and superposition solutions | We study the problem of gravity surface waves for an ideal fluid model in the (2+1)-dimensional case. We apply a systematic procedure to derive the Boussinesq equations for a given relation between the orders of four expansion parameters, the amplitude parameter $\alpha$, the long-wavelength parameter $\beta$, the tran... | https://arxiv.org/abs/2206.08964v3 | 2206.08964 | 2022-06-17 | cybersecurity |
2+1 dimensional loop quantum cosmology of Bianchi I models | We study the anisotropic Bianchi I loop quantum cosmology in 2+1 dimensions.
Both the $\mubar$ and $\mubar'$ schemes are considered in the present paper and
the following expected results are established: (i) the massless scalar field
again play the role of emergent time variables and serves as an internal clock;
(ii) ... | http://arxiv.org/abs/1602.07478v1 | 1602.07478 | 2016-02-24 | cybersecurity |
$(2+1)$-dimensional regular black holes with nonlinear electrodynamics sources | On the basis of two requirements: the avoidance of the curvature singularity
and the Maxwell theory as the weak field limit of the nonlinear
electrodynamics, we find two restricted conditions on the metric function of
$(2+1)$-dimensional regular black hole in general relativity coupled with
nonlinear electrodynamics so... | http://arxiv.org/abs/1709.09473v1 | 1709.09473 | 2017-09-27 | cybersecurity |
(2+1)$-dimensional sonic black hole from spin-orbit coupled Bose-Einstein condensate and its analogue Hawking radiation | We study the properties of a $2+1$ dimensional Sonic black hole (SBH) that
can be realised, in a quasi-two-dimensional two-component spin-orbit coupled
Bose-Einstein condensate (BEC). The corresponding equation for phase
fluctuations in the total density mode that describes phonon field in the
hydrodynamic approximatio... | http://arxiv.org/abs/1810.04860v3 | 1810.04860 | 2020-07-29 | cybersecurity |
(2+1)-dimensional Static Cyclic Symmetric Traversable Wormhole: Quasinormal Modes and Causality | In this paper we study a static cyclic symmetric traversable wormhole in
$(2+1)-$dimensional gravity coupled to nonlinear electrodynamics in anti-de
Sitter spacetime. The solution is characterized by three parameters: mass $M$,
cosmological constant $\Lambda$ and one electromagnetic parameter,
$q_{\alpha}$. The causali... | http://arxiv.org/abs/1906.04360v2 | 1906.04360 | 2019-10-26 | cybersecurity |
2+1-dimensional traversable wormholes supported by positive energy | We revisit the shapes of the throats of wormholes, including thin-shell
wormholes (TSWs) in $2+1-$dimensions. In particular, in the case of TSWs this
is done in a flat $2+1-$dimensional bulk spacetime by using the standard method
of cut-and-paste. Upon departing from a pure time-dependent circular shape
i.e., $r=a\left... | http://arxiv.org/abs/1409.2686v2 | 1409.2686 | 2015-02-17 | cybersecurity |
2+1-dimensional wormhole from a doublet of scalar fields | We present a class of exact solutions in the framework of $2+1-$dimensional
Einstein gravity coupled minimally to a doublet of scalar fields. Our solution
can be interpreted upon tuning of parameters as an asymptotically flat wormhole
as well as a particle model in $2+1-$dimensions. | http://arxiv.org/abs/1507.07257v1 | 1507.07257 | 2015-07-26 | cybersecurity |
2+1D symmetry-topological-order from local symmetric operators in 1+1D | A generalized symmetry (defined by the algebra of local symmetric operators) can go beyond group or higher group description. A theory of generalized symmetry (up to holo-equivalence) was developed in terms of symmetry-TO -- a bosonic topological order (TO) with gappable boundary in one higher dimension. We propose a g... | https://arxiv.org/abs/2310.05790v1 | 2310.05790 | 2023-10-09 | cybersecurity |
(2+1)D topological phases with RT symmetry: many-body invariant, classification, and higher order edge modes | It is common in condensed matter systems for reflection ($R$) and time-reversal ($T$) symmetry to both be broken while the combination $RT$ is preserved. In this paper we study invariants that arise due to $RT$ symmetry. We consider many-body systems of interacting fermions with fermionic symmetry groups $G_f = \mathbb... | https://arxiv.org/abs/2403.18887v1 | 2403.18887 | 2024-03-27 | cybersecurity |
$2+1$ Einstein-Klein-Gordon black holes by gravitational decoupling | In this work we study the 2+1 Einstein-Klein-Gordon system in the framework of Gravitational Decoupling. We associate the generic matter decoupling sector with a real scalar field so we can obtain a constraint which allows to close the system of differential equations. The constraint corresponds to a differential equat... | https://arxiv.org/abs/2203.00661v2 | 2203.00661 | 2022-03-01 | cybersecurity |
2+1 Flavor Domain Wall Fermion QCD Lattices: Ensemble Production and (some) Properties | The RBC and UKQCD Collaborations continue to produce 2+1 flavor domain wall
fermion ensembles, currently focusing on an ensemble with a $96^3 \times 192$
volume on SUMMIT at ORNL with $1/a \approx 2.8$ GeV, and smaller ensembles at
stronger couplings. The $1/a \approx 2.8$ GeV ensemble uses the Exact One
Flavor Algorit... | http://arxiv.org/abs/1912.13150v1 | 1912.13150 | 2019-12-31 | cybersecurity |
2+1 flavor fine lattice simulation at finite temperature with domain-wall fermions | Simulations for the thermodynamics of the 2+1 flavor QCD are performed employing chiral fermions. The use of M\"obius domain-wall fermions with stout-link smearing is more effective on the finer lattices where all the relevant chiral symmetries are realized more accurately. We report on the initial simulations near the... | https://arxiv.org/abs/2112.11771v1 | 2112.11771 | 2021-12-22 | cybersecurity |
2+1 flavor QCD simulation on a $96^4$ lattice | We generate $2+1$ flavor QCD configurations near the physical point on a
$96^4$ lattice employing the 6-APE stout smeared Wilson clover action with a
nonperturbative $c_{\rm SW}$ and the Iwasaki gauge action at $\beta=1.82$. The
physical point is estimated based on the chiral perturbation theory using
several data poin... | http://arxiv.org/abs/1511.09222v1 | 1511.09222 | 2015-11-30 | cybersecurity |
(2+1)-flavor QCD Thermodynamics from the Gradient Flow | Recently, we proposed a novel method to define and calculate the
energy-momentum tensor (EMT) in lattice gauge theory on the basis of the
Yang-Mills gradient flow [1]. In this proceedings, we summarize the basic idea
and technical steps to obtain the bulk thermodynamic quantities in lattice
gauge theory using this meth... | http://arxiv.org/abs/1511.03009v1 | 1511.03009 | 2015-11-10 | cybersecurity |
2+1 flavors QCD equation of state at zero temperature within Dyson-Schwinger equations | Within the framework of Dyson-Schwinger equations (DSEs), we discuss the
equation of state (EOS) and quark number densities of 2+1 flavors, that is to
say, $u$, $d$, and $s$ quarks. The chemical equilibrium and electric charge
neutrality conditions are used to constrain the chemical potential of different
quarks. The E... | http://arxiv.org/abs/1506.06846v1 | 1506.06846 | 2015-06-23 | cybersecurity |
(2+1) Lorentzian quantum cosmology from spin-foams: opportunities and obstacles for semi-classicality | We construct an effective cosmological spin-foam model for a (2+1) dimensional spatially flat universe, discretized on a hypercubical lattice, containing both space- and time-like regions. Our starting point is the recently proposed coherent state spin-foam model for (2+1) Lorentzian quantum gravity. The full amplitude... | https://arxiv.org/abs/2411.08109v3 | 2411.08109 | 2024-11-12 | cybersecurity |
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