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A 100um thick silicon detector with 1mm2 pad readout optimized for
sub-nanosecond time resolution has been developed and tested. Coupled to a
purposely developed amplifier based on SiGe HBT technology, this detector was
characterized at the H8 beam line at the CERN SPS. An excellent time resolution
of (106+-1)ps for silicon detectors was measured with minimum ionizing
particles.
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http://arxiv.org/abs/1511.04231v1
|
Magnetic sensing is present in our everyday interactions with consumer
electronics, and also demonstrates potential for measurement of extremely weak
biomagnetic fields, such as those of the heart and brain. In this work, we
leverage the many benefits of the micro-electromechanical systems (MEMS)
devices to fabricate a small, low power, inexpensive sensor whose resolution is
in the range of weak biomagnetic fields. The sensor works at room temperature,
and is suitable for consumer electronics integration. At present, such
biomagnetic fields can only be measured by expensive mechanisms such as optical
pumping and superconducting quantum interference devices (SQUIDs). Thus, our
sensor suggests the opening of a large phase space for medical and consumer
applications. The prototype fabrication is achieved by assembling
micro-objects, including a permanent micromagnet, onto a post-release
commercial MEMS accelerometer. With this system, we demonstrate a room
temperature MEMS magnetometer, whose design is only sensitive to gradient
magnetic fields and is generally insensitive to the Earth's uniform field. In
air, the sensor's response is linear with a resolution of 1.1 nT cm-1 and spans
over 3 decades of dynamic range to 4.6 {\mu}T cm-1. In 1 mTorr vacuum with 20
dB magnetic shielding, the sensor achieved 100 pT cm-1 resolution at resonance.
The theoretical floor of this design is 110 fT cm-1 Hz-1/2 with a resolution of
13 fT cm-1, thus these devices hold promise for both magnetocardiography (MCG)
and magnetoencephalography (MEG) applications.
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http://arxiv.org/abs/1911.10250v1
|
Frequency-resolved optical gating (FROG) is widely used to measure ultrashort
laser pulses, also providing an excellent indication of pulse-shape
instabilities by disagreement between measured and retrieved FROG traces. FROG,
however, requires -- but currently lacks -- an extremely reliable
pulse-retrieval algorithm. So, this work provides one. It uses a simple
procedure for directly retrieving the precise pulse spectrum from the measured
trace. Additionally, it implements a multi-grid scheme, also quickly yielding a
vastly improved guess for the spectral phase before implementing the entire
measured trace. As a result, it achieves 100% convergence for the three most
common variants of FROG for pulses with time-bandwidth products as high as 100,
even with traces contaminated with noise. Here we consider the
polarization-gate (PG) and transient-grating (TG) variants of FROG, which
measure amplified, UV, and broadly tunable pulses. Convergence occurs for all
of the >20,000 simulated noisy PG/TG FROG traces considered and is also faster.
|
http://arxiv.org/abs/1811.11100v2
|
Japan has committed to carbon neutrality by 2050. Emissions from the electricity sector amount to 42% of the total. Solar photovoltaics (PV) and wind comprise three quarters of global net capacity additions because of low and falling prices. This provides an opportunity for Japan to make large reductions in emissions while also reducing its dependence on energy imports. This study shows that Japan has 14 times more solar and offshore wind resources than needed to supply 100% renewable electricity. A 40 year hourly energy balance model is presented of Japan's electricity system using historical data. Pumped hydro energy storage, high voltage interconnection and dispatchable capacity (hydro, biomass and hydrogen energy) are included to balance variable generation and demand. Differential evolution is used to find the least-cost solution under various constraints. The levelized cost of electricity is found to be USD 86 per MWh for a PV-dominated system, and USD 110 per MWh for a wind-dominated system. These costs can be compared with the average system prices on the spot market in Japan of USD 102 per MWh. In summary, Japan can be self-sufficient for electricity supply at competitive costs.
|
https://arxiv.org/abs/2109.08363v1
|
https://aclanthology.org/N12-4001
|
|
Meaning is a fundamental concept in Natural Language Processing (NLP), given its aim to build systems that mean what they say to you, and understand what you say to them. In order for NLP to scale beyond partial, task-specific solutions, it must be informed by what is known about how humans use language to express and understand communicative intents. The purpose of this tutorial is to present a selection of useful information about semantics and pragmatics, as understood in linguistics, in a way that{'}s accessible to and useful for NLP practitioners with minimal (or even no) prior training in linguistics. The tutorial content is based on a manuscript in progress I am co-authoring with Prof. Alex Lascarides of the University of Edinburgh.
|
https://aclanthology.org/P18-5001
|
Weighted median, in the form of either solver or filter, has been employed in a wide range of computer vision solutions for its beneficial properties in sparsity representation. But it is hard to be accelerated due to the spatially varying weight and the median property. We propose a few efficient schemes to reduce computation complexity from O(r^2) to O(r) where r is the kernel size. Our contribution is on a new joint-histogram representation, median tracking, and a new data structure that enables fast data access. The effectiveness of these schemes is demonstrated on optical flow estimation, stereo matching, structure-texture separation, image filtering, to name a few. The running time is largely shortened from several minutes to less than 1 second. The source code is provided in the project website.
|
http://openaccess.thecvf.com/content_cvpr_2014/html/Zhang_100_Times_Faster_2014_CVPR_paper.html
|
100 years after Smoluchowski introduces his approach to stochastic processes,
they are now at the basis of mathematical and physical modeling in cellular
biology: they are used for example to analyse and to extract features from
large number (tens of thousands) of single molecular trajectories or to study
the diffusive motion of molecules, proteins or receptors. Stochastic modeling
is a new step in large data analysis that serves extracting cell biology
concepts. We review here the Smoluchowski's approach to stochastic processes
and provide several applications for coarse-graining diffusion, studying
polymer models for understanding nuclear organization and finally, we discuss
the stochastic jump dynamics of telomeres across cell division and stochastic
gene regulation.
|
http://arxiv.org/abs/1612.08381v1
|
A report by Brillouin (from Perrin's laboratory) on the rate of adsorption of `granules' to a glass plate [\textit{Ann. Chim. Phys.} 27 (1912) 412--23] prompted Marian von Smoluchowski (MvS) to interpret the data in terms of his newly developed theory of restricted Brownian motion. Placing an adsorbing wall at $x=0$, he modelled the particle concentration $n(x,t)$ as that solution of the diffusion equation which vanished at the wall, a boundary condition (BC) hereafter called SBC. A gaping discrepancy between his theory and Brillouin's data elicited a suggestion from MvS (that a particle might not adhere to the wall on every impact), but no further action -- other than that of applying his theory to spherically symmtric systems. In a paper written before, but published shortly after MvS's untimely death [\textit{Proc. Roy. Acad. Amst.} 20 (1918) 642--58], H. C. Burger erected a new and sturdier framework, which led him to an alternative BC, $D(\partial n/\partial x)_{x=0}=\varkappa n(0,t)$, applicable to a surface with an arbitrary absorption probability ($1\leq\varepsilon\leq 0$); a fallacy (that subsequently claimed more victims, including the present author) prevented him from deducing the correct expression for $\varkappa$. Burger's approach became ``The Road Not Taken'', while the SBC became the cornerstone of colloidal coagulation and bimoleculer reaction kinetics. Burger's approach (but not the ABC) was partly rediscovered by Kolmogorov, and used by Sveshnikov and Fuchs.The emended version of Burger's BC is shown here to coincide with that deduced from the Klein-Kramers equation [\textit{Phys. Rev. Lett.} \textbf{49} (1982) 304--07; \textit{J. Chem. Phys.} \textbf{78} (1983) 2710--12] and the Lorentz model of random flights [\textit{J. Phys. Chem.} \textbf{86} (1982) 4750--56].
|
https://arxiv.org/abs/2404.17021v1
|
An elementary survey of mathematical cosmology is presented. We cover certain key ideas and developments in a qualitative way, from the time of the Einstein static universe in 1917 until today. We divide our presentation into four main parts, the first part containing important cosmologies discovered until 1960. The second period (1960-80) contains discussions of geometric extensions of the standard cosmology, singularities, chaotic behaviour, and the initial input of particle physics ideas into cosmology. Our survey for the third period (1980-2000) continues with brief descriptions of the main ideas of inflation, the multiverse, quantum, Kaluza-Klein, and string cosmologies, wormholes and baby universes, cosmological stability, and modified gravity. The last period which ends today includes various more advanced topics such as M-theoretic cosmology, braneworlds, the landscape, topological issues, the measure problem, genericity, dynamical singularities, and dark energy. We emphasize certain threads that run throughout the whole period of development of theoretical cosmology and underline their importance in the overall structure of the field. We end this outline with an inclusion of the abstracts of all papers contributed to the Philosophical Transactions of the Royal Society A, Theme Issue `The Future of Mathematical Cosmology'.
|
https://arxiv.org/abs/2203.16443v1
|
Robust and credible material flow data are required to support the ongoing efforts to reconcile the economic and social benefits of plastics with their human and environmental health impacts. This study presents a global, but regionalized, life cycle material flow analysis (MFA) of all plastic polymers and applications for the period 1950-2020. It also illustrates how this dataset can be used to generate possible scenarios for the next 30 years. The historical account documents how the relentless growth of plastic production and use has consistently outpaced waste management systems worldwide and currently generates on the order of 60 Mt of mismanaged plastic waste annually. The scenarios show that robust interventions are needed to avoid annual plastic waste mismanagement from doubling by 2050.
|
https://arxiv.org/abs/2411.13618v1
|
We are experiencing a period of extreme intellectual effervescence in the
area of cosmology. A huge volume of observational data in unprecedented
quantity and quality and a more consistent theoretical framework propelled
cosmology to an era of precision, turning the discipline into a cutting-edge
area of contemporary science. Observations with type Ia Supernovae (SNe Ia),
showed that the expanding Universe is accelerating, an unexplained fact in the
traditional decelerated model. Identifying the cause of this acceleration is
the most fundamental problem in the area. As in the scientific renaissance, the
solution will guide the course of the discipline in the near future and the
possible answers (whether dark energy, some extension of general relativity or
a still unknown mechanism) should also leverage the development of physics. In
this context, without giving up a pedagogical approach, we present an overview
of both the main theoretical results and the most significant observational
discoveries of cosmology in the last 100 years. The saga of cosmology will be
presented in a trilogy. In this article (Part I), based on the articles by
Einstein, de Sitter, Friedmann, Lema\^itre and Hubble, we will describe the
period between the origins of cosmology and the discovery of Universal
expansion (1929). In Part II, we will see the period from 1930 to 1997, closing
with the old standard decelerated model. The Part III will be entirely devoted
to the accelerated model of the universe, the cosmic paradigm of the XXI
century.
|
http://arxiv.org/abs/1709.03693v1
|
The Cosmological Constant $\Lambda$, in different incarnations, has been with
us for 100 years. Many surveys of dark energy are underway, indicating so far
that the data are consistent with a dark energy equation of state of $w=-1$,
i.e. a $\Lambda$ term in Einstein's equation, although time variation of $w$ is
not yet ruled out. The ball is now back in the theoreticians' court, to explain
the physical meaning of $\Lambda$. We discuss sociological aspects of this
field, in particular to what extent the agreement on the cold dark matter +
$\Lambda$ concordance model is a result of the globalization of research and
over-communication.
|
http://arxiv.org/abs/1704.00069v1
|
We take the occasion of this article to review one hundred years of the physical and mathematical study of the Ising model. The model, introduced by Lenz in 1920, has been at the cornerstone of many major revolutions in statistical mechanics. We wish, through its history, to outline some of these amazing developments. We restrict our attention to the ferromagnetic nearest-neighbour model on the hypercubic lattice, and essentially focus on what happens at or near the so-called critical point.
|
https://arxiv.org/abs/2208.00864v1
|
Einsteins general theory of relativity is one of the most important
accomplishments in the history of science. Its experimental verification a
century ago is therefore an essential milestone that is worth celebrating in
full. We reassess the importance of one of the two expeditions that made these
measurements possible, a story that involves a sense of adventure and
scientific ingenuity in equal measure.
|
http://arxiv.org/abs/1907.10687v1
|
We discuss the asymptotics of the eigenvalue counting function for partial
differential operators and related expressions paying the most attention to the
sharp asymptotics. We consider Weyl asymptotics, asymptotics with Weyl
principal parts and correction terms and asymptotics with non-Weyl principal
parts. Semiclassical microlocal analysis, propagation of singularities and
related dynamics play crucial role.
We start from the general theory, then consider Schr\"odinger and Dirac
operators with the strong magnetic field and, finally, applications to the
asymptotics of the ground state energy of heavy atoms and molecules with or
without a magnetic field.
|
http://arxiv.org/abs/1608.03963v2
|
Current systems and formalisms for representing incomplete information generally suffer from at least one of two weaknesses. Either they are not strong enough for representing results of simple queries, or the handling and processing of the data, e.g. for query evaluation, is intractable. In this paper, we present a decomposition-based approach to addressing this problem. We introduce world-set decompositions (WSDs), a space-efficient formalism for representing any finite set of possible worlds over relational databases. WSDs are therefore a strong representation system for any relational query language. We study the problem of efficiently evaluating relational algebra queries on sets of worlds represented by WSDs. We also evaluate our technique experimentally in a large census data scenario and show that it is both scalable and efficient.
|
https://arxiv.org/abs/cs/0606075v2
|
We demonstrate a self-homodyne detection method to stabilize a continuous-wave 1550-nm laser to a 1-km optical fiber delay line, achieving a frequency instability of 6.3x10<sup>-15</sup> at a 16-ms averaging time. This result, limited by fiber thermal noise, is achieved without the need for a vacuum system, highlighting the potential of our approach for ultra-stable laser systems in non-laboratory environments. The system utilizes only a few passive fiber optic components and a single balanced photodetector, significantly simplifying the laser stabilization process while maintaining high performance. The entire optical setup is compactly packaged in a portable metal air-tight case.
|
https://arxiv.org/abs/2409.04681v2
|
In the $\{-1,0,1\}$-APSP problem the goal is to compute all-pairs shortest
paths (APSP) on a directed graph whose edge weights are all from $\{-1,0,1\}$.
In the (min,max)-product problem the input is two $n\times n$ matrices $A$ and
$B$, and the goal is to output the (min,max)-product of $A$ and $B$.
This paper provides a new algorithm for the $\{-1,0,1\}$-APSP problem via a
simple reduction to the target-(min,max)-product problem where the input is
three $n\times n$ matrices $A,B$, and $T$, and the goal is to output a Boolean
$n\times n$ matrix $C$ such that the $(i,j)$ entry of $C$ is 1 if and only if
the $(i,j)$ entry of the (min,max)-product of $A$ and $B$ is exactly the
$(i,j)$ entry of the target matrix $T$. If (min,max)-product can be solved in
$T_{MM}(n) = \Omega(n^2)$ time then it is straightforward to solve
target-(min,max)-product in $O(T_{MM}(n))$ time. Thus, given the recent result
of Bringmann, K\"unnemann, and Wegrzycki [STOC 2019], the $\{-1,0,1\}$-APSP
problem can be solved in the same time needed for solving approximate APSP on
graphs with positive weights.
Moreover, we design a simple algorithm for target-(min,max)-product when the
inputs are restricted to the family of inputs generated by our reduction. Using
fast rectangular matrix multiplication, the new algorithm is faster than the
current best known algorithm for (min,max)-product.
|
http://arxiv.org/abs/1911.06132v1
|
In recent years, Large Language Models have revolutionized the field of natural language processing, showcasing an impressive rise predominantly in English-centric domains. These advancements have set a global benchmark, inspiring significant efforts toward developing Arabic LLMs capable of understanding and generating the Arabic language with remarkable accuracy. Despite these advancements, a critical challenge persists: the potential bias in Arabic LLMs, primarily attributed to their reliance on datasets comprising English data that has been translated into Arabic. This reliance not only compromises the authenticity of the generated content but also reflects a broader issue -the scarcity of original quality Arabic linguistic data. This study aims to address the data scarcity in the Arab world and to encourage the development of Arabic Language Models that are true to both the linguistic and nuances of the region. We undertook a large-scale data mining project, extracting a substantial volume of text from the Common Crawl WET files, specifically targeting Arabic content. The extracted data underwent a rigorous cleaning and deduplication process, using innovative techniques to ensure the integrity and uniqueness of the dataset. The result is the 101 Billion Arabic Words Dataset, the largest Arabic dataset available to date, which can significantly contribute to the development of authentic Arabic LLMs. This study not only highlights the potential for creating linguistically and culturally accurate Arabic LLMs but also sets a precedent for future research in enhancing the authenticity of Arabic language models.
|
https://arxiv.org/abs/2405.01590v1
|
We present our second catalog of quadruple star candidates, containing 101 systems discovered in TESS Full-Frame Image data. The targets were initially detected as eclipsing binary stars with the help of supervised machine learning methods applied to sectors Sectors 1 through 54. A dedicated team of citizen scientists subsequently identified through visual inspection two sets of eclipses following two different periods. All 101 systems presented here pass comprehensive photocenter motion tests confirming that both sets of eclipses originate from the target star. Some of the systems exhibit prominent eclipse time variations suggesting dynamical interactions between the two component binary stars. One target is an eclipsing quintuple candidate with a (2+1)+2 hierarchical configuration, such that the (2+1) subsystem produces eclipses on the triple orbit as well. Another has recently been confirmed as the second shortest period quadruple reported to date. This catalog provides ephemerides, eclipse depths and durations, sample statistics, and highlights potentially interesting targets for future studies.
|
https://arxiv.org/abs/2309.14200v1
|
We present explicit formulas - that are also computer code - for 101
real-life quantitative trading alphas. Their average holding period
approximately ranges 0.6-6.4 days. The average pair-wise correlation of these
alphas is low, 15.9%. The returns are strongly correlated with volatility, but
have no significant dependence on turnover, directly confirming an earlier
result based on a more indirect empirical analysis. We further find empirically
that turnover has poor explanatory power for alpha correlations.
|
http://arxiv.org/abs/1601.00991v3
|
Various properties of Jovian trojan asteroids such as composition, rotation periods, and photometric amplitudes, or the rate of binarity in the population can provide information and constraints on the evolution of the group and of the Solar System itself. Here we present new photometric properties of 45 Jovian trojans from the K2 mission of the Kepler space telescope, and present phase-folded light curves for 44 targets, including (11351) Leucus, one of the targets of the Lucy mission. We extend our sample to 101 asteroids with previous K2 Trojan measurements, then compare their combined amplitude- and frequency distributions to other ground-based and space data. We show that there is a dichotomy in the periods of Trojans with a separation at $\sim 100$ hr. We find that 25% of the sample are slow rotators (P$\geq$30 hr), which excess can be attributed to binary objects. We also show that 32 systems can be classified as potential detached binary systems. Finally, we calculate density and rotation constraints for the asteroids. Both the spin barrier and fits to strengthless ellipsoid models indicate low densities and thus compositions similar to cometary and TNO populations throughout the sample. This supports the scenario of outer Solar System origin for Jovian trojans.
|
https://arxiv.org/abs/2102.09447v1
|
Social media is a great source of data for users reporting information and regarding their health and how various things have had an effect on them. This paper presents various approaches using Transformers and Large Language Models and their ensembles, their performance along with advantages and drawbacks for various tasks of SMM4H'24 - Classifying texts on impact of nature and outdoor spaces on the author's mental health (Task 3), Binary classification of tweets reporting their children's health disorders like Asthma, Autism, ADHD and Speech disorder (task 5), Binary classification of users self-reporting their age (task 6).
|
https://arxiv.org/abs/2410.15998v1
|
We present results on the world's first over 100 PFLOPS single precision lattice QCD quark solver on the japanese new supercomputer Fugaku. We achieve a factor 38 time speedup from the supercomputer K on the same problem size, $192^4$, with 102 PFLOPS, 10% floating-point operation efficiency against single precision floating-point operation peak. The evaluation region is the single precision BiCGStab for a Clover-Wilson Dirac matrix with Schwarz Alternating Procedure domain decomposition preconditioning using Jacobi iteration for the local domain matrix inversion.
|
https://arxiv.org/abs/2109.10687v1
|
We quantify the accuracy of different non-self-consistent and self-consistent
spin-orbit coupling (SOC) treatments in Kohn-Sham and hybrid density-functional
theory by providing a band structure benchmark set for the valence and
low-lying conduction energy bands of 103 inorganic compounds, covering chemical
elements up to Po. Reference energy band structures for the PBE density
functional are obtained using the full-potential (linearized) augmented plane
wave code Wien2k, employing its self-consistent treatment of SOC including
Dirac-like p$^{1/2}$ orbitals in the basis set. We use this benchmark set to
benchmark a computationally simpler, non-self-consistent all-electron treatment
of SOC based on scalar-relativistic orbitals and numeric atom-centered orbital
basis functions. For elements up to Z$\approx$50, both treatments agree
virtually exactly. For the heaviest elements considered (Tl, Pb, Bi, Po), the
band structure changes due to SOC are captured with a relative deviation of 11%
or less. For different density functionals (PBE vs. the hybrid HSE06), we show
that the effect of spin-orbit coupling is usually similar but can be dissimilar
if the qualitative features of the predicted underlying scalar-relativistic
band structures do not agree. All band structures considered in this work are
available online via the NOMAD Repository to aid in future benchmark studies
and methods development.
|
http://arxiv.org/abs/1705.01804v2
|
Generating a powerful and quasistatic magnetic field within the confines of a tabletop laboratory experiment has proven to be a persistent challenge. The creation of magnetized high-energy-density plasma through such experiments presents significant opportunities for exploring several terrestrial as well as astrophysical phenomena, apart from controlling relativistic electron transport, directly relevant for fusion schemes. Here we demonstrate that the modest magnetic field (10$^{-3}$ megagauss ) in a common, readily available Neodymium magnet is amplified to 10's of megagauss levels lasting a few picoseconds, when excited by an ultraintense, femtosecond laser pulse. The experimental findings are strongly supported by particle-in-cell simulations, which not only validate the observations but also unveil a potential dynamo mechanism responsible for the enhancement and amplification of the axial magnetic field. These outcomes are of utmost importance in comprehending the intricacies of relativistic electron transport and the realm of magnetized laboratory astrophysics.
|
https://arxiv.org/abs/2504.15094v2
|
An ultrafast laser delivering 10.4 kW average output power based on coherent combination of twelve stepindex fiber amplifiers is presented. The system emits close-to-transform-limited 254 fs pulses at 80 MHz repetition rate, has a high beam quality (M2<=1.2), and a low relative intensity noise of 0.56% in the frequency range of from 1 Hz to 1 MHz. Automated spatiotemporal alignment allows for hands-off operation.
|
https://arxiv.org/abs/2101.08501v1
|
Aims. GRB 190829A (z = 0.0785), detected by Fermi and Swift with two emission episodes separated by a quiescent gap of ~40 s, was also observed by the H.E.S.S. telescopes at Very-High Energy (VHE). We present the 10.4m GTC observations of the afterglow of GRB 190829A and underlying supernova and compare it against a similar GRB 180728A and discuss the implications on underlying physical mechanisms producing these two GRBs. Methods. We present multi-band photometric data along with spectroscopic follow-up observations taken with the 10.4m GTC telescope. Together with the data from the prompt emission, the 10.4m GTC data are used to understand the emission mechanisms and possible progenitor. Results. A detailed analysis of multi-band data of the afterglow demands cooling frequency to pass between the optical and X-ray bands at early epochs and dominant with underlying SN 2019oyw later on. Conclusions. Prompt emission temporal properties of GRB 190829A and GRB 180728A are similar, however the two pulses seem different in the spectral domain. We found that the supernova (SN) 2019oyw associated with GRB 190829A, powered by Ni decay, is of Type Ic-BL and that the spectroscopic/photometric properties of this SN is consistent with those observed for SN 1998bw but evolved comparatively early.
|
https://arxiv.org/abs/2009.04021v1
|
We report $^{105}$Pd NMR and NQR measurements on a single crystal of
Ce$_3$Pd$_{20}$Si$_6$, where antiferroquadrupolar and antiferromagnetic orders
develop at low temperature. From the analysis of NQR and NMR spectra, we have
determined the electric field gradient (EFG) tensors and the anisotropic Knight
shift ($K$) components for both inequivalent Pd sites - Pd($32f$) and
Pd($48h$). The observed EFG values are in excellent agreement with our
state-of-the-art DFT calculations. The principal values of the quadrupolar
coupling are $(20.37 \pm 0.02)$ MHz and $(5.45 \pm 0.02)$ MHz, for the
Pd($32f$) and Pd($48h$) site, respectively, which is large compared to the
Larmor frequency defined by the gyromagnetic constant $\gamma = 1.94838$ MHz/T
for $^{105}$Pd. Therefore, the complete knowledge of $K$ and the EFG tensors is
crucial to establish the correspondence between NMR spectra and
crystallographic sites, which is needed for a complete analysis of the magnetic
structure, static spin susceptibility, and the spin-lattice relaxation rate
data and a better understanding of the groundstate of Ce$_3$Pd$_{20}$Si$_6$.
|
http://arxiv.org/abs/1911.09952v2
|
Based on the technique of periodically poled lithium niobate (PPLN)
waveguide, up-conversion single-photon detection at 1.064-{\mu}m is
demonstrated. We have achieved a system photon detection efficiency (DE) of
32.5% with a very low noise count rate (NCR) of 45 counts per second (cps) by
pumping with a 1.55-{\mu}m-band single frequency laser using the
long-wavelength pumping technique and exploiting volume Bragg grating (VBG) as
a narrow band filter. Replacing the VBG with a combination of adequate
dielectric filters, a DE of up to 38% with a NCR of 700 cps is achieved, making
the overall system more stable and practical. The up-conversion single-photon
detector (SPD) operating at 1.064 {\mu}m can be a promising robust counter and
find usage in many fields.
|
http://arxiv.org/abs/1703.10838v1
|
To solve the Cd puzzle (spherical nucleus puzzle), I have proposed the concept ``spherical-like nucleus''. Since shape coexistence often occurs in such nuclei, explicit spherical-like spectra are not easily identified. In this Letter, I finally find the direct evidence for the existence of the spherical-like nucleus. $^{106}$Pd is in fact a typical spherical-like nucleus. The low-lying parts, up to the $10_{1}^{+}$ state, under 4000 keV, of the spherical-like spectra are verified. By comparison, new theory outperforms the IBM-2. This result completely disproves the possibility of the phonon excitations of the spherical nucleus in the Cd-Pd nuclei region.
|
https://arxiv.org/abs/2501.10925v3
|
I investigate $^{10}$B+$\alpha$ cluster states of $^{14}$N with a
$^{10}$B+$\alpha$ cluster model. Near the $\alpha$-decay threshold energy, I
obtain $K^\pi=3^+$ and $K^\pi=1^+$ rotational bands having
$^{10}$B($3^+$)+$\alpha$ and $^{10}$B($1^+$)+$\alpha$ components, respectively.
I assign the band-head state of the $K^\pi=3^+$ band to the experimental $3^+$
at $E_x$=13.19 MeV of $^{14}$N observed in $\alpha$ scattering reactions by
$^{10}$B and show that the calculated $\alpha$-decay width is consistent with
the experimental data. I discuss an $\alpha$-cluster motion around the $^{10}$B
cluster and show that $^{10}$B+$\alpha$ cluster states contain significant
components of a linear-chain 3$\alpha$ configuration, in which an $\alpha$
cluster is localized in the longitudinal direction around the deformed $^{10}$B
cluster.
|
http://arxiv.org/abs/1505.05591v1
|
The Cluster Shell Model (CSM)describes light nuclei in terms of $k-\alpha$ particles and $x$ extra nucleons, in which the extra nucleon move in the deformed field generated by the geometric configuration of $\alpha$-particles. We present the first study for the case $x=2$ nucleons in application to $^{10}Be$ as a cluster of two $\alpha$-particles and two neutrons.
|
https://arxiv.org/abs/2309.14505v1
|
We present a determination of optical potentials for $^{10}$Be-nucleus collisions using the double-folding method to compute the real part and Kramers-Kronig dispersion relations to derive the imaginary part. As microscopic inputs we use chiral effective field theory nucleon-nucleon interactions at next-to-next-to-leading order combined with state-of-the-art nucleonic densities. With these potentials, we compute elastic scattering cross sections for the exotic nucleus 10 Be off various targets, and compare them to experiment. Without any fitting parameter, we obtain good agreement with data. For collisions on light targets, we observe significant uncertainty related to the short-range physics, whereas for heavy targets that uncertainty remains small.
|
https://arxiv.org/abs/2205.13987v2
|
Significant suppression of radiation in 3D structured media with small refractive index 1.4-1.6, such as of glass or polymers, is a desirable feature yet to be obtained. For periodical structures this is realised at frequencies of the complete photonic band gap (CPBG), which up to now was demonstrated to open for materials with refractive index of at least 1.9. We present here a quasiperiodic 3D structure consisting of multiple overlapping gratings with a homogeneous distribution of Bragg peaks on a sphere in reciprocal space, which allows efficient suppression of emission. Recently we have presented the theoretical model, considering interaction with the neighbouring gratings only, that estimates a finite CPBG for arbitrarily small refractive indices and thus complete emission suppression in infinite structures. However, numerical simulations demonstrate a finite leakage of power from emitter not predicted by the model. Still the simulations show -10 dB suppression in 3D structures with optimised number of gratings. Astonishingly, as we show here, this limit is almost independent of the refractive index contrast. Also, the structures with a defined number of gratings show maximal suppression at certain refractive indices, losing the suppression even at higher refractive indices. The -10 dB suppression is demonstrated for refractive index contrast as low as 1.30.
|
https://arxiv.org/abs/2209.15463v1
|
We remark that the two 10D massive deformations of the $N=2$ maximal type IIA
supergravity (Romans and HLW supergravity) are associated to the low energy
limit of the uplift to 10D of M2-brane torus bundles with parabolic monodromy
linearly and non-linearly realized respectively. Romans supergravity
corresponds to M2-brane compactified on a twice-punctured torus bundle.
|
http://arxiv.org/abs/1511.04784v1
|
Using the pure spinor master action for 10D super-Yang-Mills in the gauge $b_{0}V = Q\Xi$, tree-level scattering amplitudes are calculated through the perturbiner method, and shown to match those obtained from pure spinor CFT techniques. We find kinematic numerators made of nested $b$-ghost operators, and show that the Siegel gauge condition $b_{0}V = 0$ gives rise to color-kinematics duality satisfying numerators whose Jacobi identity follows from the Jacobi identity of a kinematic algebra.
|
https://arxiv.org/abs/2108.11708v1
|
We dimensionally reduce the bosonic sector of 10D Euclidean type IIA
supergravity over a Calabi-Yau three-fold. The resulting theory describes the
bosonic sector of 4D, N = 2 Euclidean supergravity coupled to vector- and
hyper-multiplets.
We show that the scalar target manifold of the vector-multiplets is
projective special para-Kahler, and is therefore of split signature, whereas
the target manifold of the hyper-multiplets is (positive-definite) quaternionic
Kahler.
|
http://arxiv.org/abs/1503.05095v3
|
The realization of high-frequency unipolar quantum optoelectronic devices enables the demonstration of high bitrate free space data transmission in the second atmospheric window. Data-bits are written onto the laser emission using a large bandwidth amplitude modulator that operates by shifting the absorption of an optical transition in and out of the laser frequency.
|
https://arxiv.org/abs/2110.06572v1
|
A coherent XY machine (CXYM) is a physical spin simulator that can simulate the XY model by mapping XY spins onto the continuous phases of non-degenerate optical parametric oscillators (NOPOs). Here, we demonstrated a large-scale CXYM with >47,000 spins by generating 10-GHz-clock time-multiplexed NOPO pulses via four-wave mixing in a highly nonlinear fiber inside a fiber ring cavity. By implementing a unidirectional coupling from the i-th pulse to the (i+1)-th pulse with a variable 1-pulse delay planar lightwave circuit interferometer, we successfully controlled the effective temperature of a one-dimensional XY spin network within two orders of magnitude.
|
https://arxiv.org/abs/2307.03333v2
|
Coherent frequency division of high-stability optical sources permits the extraction of microwave signals with ultra-low phase noise, enabling their application to systems with stringent timing precision. To date, the highest performance systems have required tight phase stabilization of laboratory grade optical frequency combs to Fabry-Perot optical reference cavities for faithful optical-to-microwave frequency division. This requirement limits the technology to highly-controlled laboratory environments. Here, we employ a transfer oscillator technique, which employs digital and RF analog electronics to coherently suppress additive optical frequency comb noise. This relaxes the stabilization requirements and allows for the extraction of multiple independent microwave outputs from a single comb, while at the same time, permitting low-noise microwave generation from combs with higher noise profiles. Using this method we transferred the phase stability of two high-Finesse optical sources at 1157 nm and 1070 nm to two independent 10 GHz signals using a single frequency comb. We demonstrated absolute phase noise below -106 dBc/Hz at 1-Hz from carrier with corresponding 1 second fractional frequency instability below $2\times10^{-15}$. Finally, the latter phase noise levels were attainable for comb linewidths broadened up to 2 MHz, demonstrating the potential for out-of lab use with low SWaP lasers.
|
https://arxiv.org/abs/2110.00593v1
|
In practical satellite-based quantum key distribution (QKD) systems, the preparation and transmission of polarization-encoding photons suffer from complex environmental effects and high channel-loss. Consequently, the hinge to enhancing the secure key rate (SKR) lies in achieving robust, low-error and high-speed polarization modulation. Although the schemes that realize self-compensation exhibit remarkable robustness. Their modulation speed is constrained to approximately 2 GHz to avoid the interaction between the electrical signal and the reverse optical pulses. Here we utilize the non-reciprocity of the lithium niobate modulators and eliminate the modulation on the reverse optical pulses. As this characteristic is widely available in the radio-frequency band, the modulation speed is no longer limited by the self-compensating optics and can be further increased. The measured average intrinsic QBER of the different polarization states at 10 GHz system repetition frequency is as low as 0.53% over 10 min without any compensation. And the experiment simulation shows that the proposed scheme extends the transmission distance to more than 350 km. Our work can be be efficient performed to the high-speed and high-loss satellite-based quantum communication scenario.
|
https://arxiv.org/abs/2411.08358v1
|
Generation of quantum light source is a promising technique to overcome the standard quantum limit in precision measurement. Here, we demonstrate an experimental generation of quadrature squeezing resonating on the cesium D2 line down to 10 Hz for the first time. The maximum squeezing in audio frequency band is 5.57 dB. Moreover, we have presented a single-photon modulation locking to control the squeezing angle, while effectively suppressing the influence of laser noise on low-frequency squeezing. The whole system operates steadily for hours. The generated low-frequency quantum light source can be applied in quantum metrology,light-matter interaction investigation and quantum memory in the audio frequency band and even below.
|
https://arxiv.org/abs/2209.07920v3
|
We propose a novel procedure to generate pseudo mandarin speech data named as CAMP (character audio mix up), which aims at generating audio from a character scale. We also raise a method for building a mandarin character scale audio database adaptive to CAMP named as META-AUDIO, which makes full use of audio data and can greatly increase the data diversity of the database. Experiments show that our CAMP method is simple and quite effective. For example, we train models with 10 hours of audio data in AISHELL-1 and pseudo audio data generated by CAMP, and achieve a competitive 11.07 character error rate (CER). Besides, we also perform training with only 10 hours of audio data in AIDATATANG dataset and pseudo audio data generated by CAMP, which again achieves a competitive 8.26 CER.
|
https://arxiv.org/abs/2210.13067v1
|
The widespread deployment of InfRared Small-Target Detection(IRSTD) algorithms on edge devices necessitates the exploration of model compression techniques. Binary neural networks (BNNs) are distinguished by their exceptional efficiency in model compression. However, the small size of infrared targets introduces stringent precision requirements for the IRSTD task, while the inherent precision loss during binarization presents a significant challenge. To address this, we propose the Binarized Infrared Small-Target Detection Network (BiisNet), which preserves the core operations of binarized convolutions while integrating full-precision features into the network's information flow. Specifically, we propose the Dot-Binary Convolution, which retains fine-grained semantic information in feature maps while still leveraging the binarized convolution operations. In addition, we introduce a smooth and adaptive Dynamic Softsign function, which provides more comprehensive and progressively finer gradient during back-propagation, enhancing model stability and promoting an optimal weight distribution.Experimental results demonstrate that BiisNet not only significantly outperforms other binary architectures but also demonstrates strong competitiveness among state-of-the-art full-precision models.
|
https://arxiv.org/abs/2503.02662v1
|
We consider the integers having the property of reversing when multiplied by
a specific integer k. First, we proved that k should be either 1, 4 or 9.
Second, we classify these integers as (10, 1)- reverse multiples, (10, 4)-
reverse multiples and (10, 9)- reverse multiples. Then we conclude their
general form.
|
http://arxiv.org/abs/1503.07848v2
|
Fix a planar graph $G$ and a list-assignment $L$ with $|L(v)|=10$ for all $v\in V(G)$. Let $\alpha$ and $\beta$ be $L$-colorings of $G$. A recoloring sequence from $\alpha$ to $\beta$ is a sequence of $L$-colorings, beginning with $\alpha$ and ending with $\beta$, such that each successive pair in the sequence differs in the color on a single vertex of $G$. We show that there exists a constant $C$ such that for all choices of $\alpha$ and $\beta$ there exists a recoloring sequence $\sigma$ from $\alpha$ to $\beta$ that recolors each vertex at most $C$ times. In particular, $\sigma$ has length at most $C|V(G)|$. This confirms a conjecture of Dvo\v{r}\'{a}k and Feghali. For our proof, we introduce a new technique for quickly showing that many configurations are reducible. We believe this method may be of independent interest and will have application to other problems in this area.
|
https://arxiv.org/abs/2411.00679v2
|
We report the first quantum key distribution (QKD) systems capable of
delivering sustainable, real-time secure keys continuously at rates exceeding
10 Mb/s. To achieve such rates, we developed high speed post-processing
modules, achieving maximum data throughputs of 60 MC/s, 55 Mb/s, and 108 Mb/s
for standalone operation of sifting, error correction and privacy amplification
modules, respectively. The photonic layer of the QKD systems features
high-speed single photon detectors based on self-differencing InGaAs avalanche
photodiodes, phase encoding using asymmetric Mach-Zehnder interferometer, and
active stabilization of the interferometer phase and photon polarisation. An
efficient variant of the decoy-state BB84 protocol is implemented for security
analysis, with a large dataset size of $10^8$ bits selected to mitigate
finite-size effects. Over a 2 dB channel, a record secure key rate of 13.72
Mb/s has been achieved averaged over 4.4 days of operation. We confirm the
robustness and long-term stability on a second QKD system continuously running
for 1 month without any user intervention.
|
http://arxiv.org/abs/1807.04484v1
|
High resolution images are widely used in our daily life, whereas high-speed video capture is challenging due to the low frame rate of cameras working at the high resolution mode. Digging deeper, the main bottleneck lies in the low throughput of existing imaging systems. Towards this end, snapshot compressive imaging (SCI) was proposed as a promising solution to improve the throughput of imaging systems by compressive sampling and computational reconstruction. During acquisition, multiple high-speed images are encoded and collapsed to a single measurement. After this, algorithms are employed to retrieve the video frames from the coded snapshot. Recently developed Plug-and-Play (PnP) algorithms make it possible for SCI reconstruction in large-scale problems. However, the lack of high-resolution encoding systems still precludes SCI's wide application. In this paper, we build a novel hybrid coded aperture snapshot compressive imaging (HCA-SCI) system by incorporating a dynamic liquid crystal on silicon and a high-resolution lithography mask. We further implement a PnP reconstruction algorithm with cascaded denoisers for high quality reconstruction. Based on the proposed HCA-SCI system and algorithm, we achieve a 10-mega pixel SCI system to capture high-speed scenes, leading to a high throughput of 4.6G voxels per second. Both simulation and real data experiments verify the feasibility and performance of our proposed HCA-SCI scheme.
|
https://arxiv.org/abs/2106.15765v2
|
Utilization enhancement is a key concern to cluster owners. Google's cluster
manager named Borg manages its clusters at an overall utilization higher than
many others' clusters. Recently, Google has disclosed the details of its
powerful cluster manager Borg. Quite a few lessons are summarized from the Borg
experiences. Nevertheless, we find that more can be learned if the Borg design
is correlated with the trace analysis of a Google cluster managed by Borg.
There is one such trace released four years ago. In this paper, we analyze the
Google cluster trace and make 10 observations not found in previous analyses.
We also correlates the results of our analysis and previous analyses to the
Borg design, such that we find two measures that can possibly further improve
cluster utilization over Borg.
|
http://arxiv.org/abs/1508.02111v2
|
We will state 10 problems, and solve some of them, for partitions in triangle-free graphs related to Erd\H{o}s' Sparse Half Conjecture. Among others we prove the following variant of it: For every sufficiently large even integer $n$ the following holds. Every triangle-free graph on $n$ vertices has a partition $V(G)=A\cup B$ with $|A|=|B|=n/2$ such that $e(G[A])+e(G[B])\leq n^2/16$. This result is sharp since the complete bipartite graph with class sizes $3n/4$ and $n/4$ achieves equality, when $n$ is a multiple of 4. Additionally, we discuss similar problems for $K_4$-free graphs.
|
https://arxiv.org/abs/2203.15764v1
|
In this paper the results of a beam test characterization campaign of 3D trench silicon pixel sensors are presented. A time resolution in the order of 10 ps was measured both for non-irradiated and irradiated sensors up to a fluence of $2.5 \cdot 10^{16}\,1\,MeV\, n_{eq}\,cm^{-2}$. This feature and a detection efficiency close to $99\%$ make this sensors one of the best candidates for 4D tracking detectors in High-Energy-Physics experiments.
|
https://arxiv.org/abs/2209.14632v2
|
Boggle logic puzzles are based on the popular word game Boggle, where you are
given list of words, and your goal is to recreate a Boggle board. In this paper
we give an overview of known results and then propose a number of problems
related to these puzzles.
|
http://arxiv.org/abs/1506.04173v1
|
Loss of key personnel has always been a risk for research software projects. Key members of the team may have to step away due to illness or burnout, to care for a family member, from a loss of financial support, or because their career is going in a new direction. Today, though, political and financial changes are putting large numbers of researchers out of work simultaneously, potentially leaving large amounts of research software abandoned. This article presents ten tips to help researchers ensure that the software they have built will continue to be usable after they have left their present job -- whether in the course of voluntary career moves or researcher mobility, but particularly in cases of involuntary departure due to political or institutional changes.
|
https://arxiv.org/abs/2505.06484v1
|
Foundation models--such as GPT, CLIP, and DINO--have achieved revolutionary progress in the past several years and are commonly believed to be a promising approach for general-purpose AI. In particular, self-supervised learning is adopted to pre-train a foundation model using a large amount of unlabeled data. A pre-trained foundation model is like an ``operating system'' of the AI ecosystem. Specifically, a foundation model can be used as a feature extractor for many downstream tasks with little or no labeled training data. Existing studies on foundation models mainly focused on pre-training a better foundation model to improve its performance on downstream tasks in non-adversarial settings, leaving its security and privacy in adversarial settings largely unexplored. A security or privacy issue of a pre-trained foundation model leads to a single point of failure for the AI ecosystem. In this book chapter, we discuss 10 basic security and privacy problems for the pre-trained foundation models, including six confidentiality problems, three integrity problems, and one availability problem. For each problem, we discuss potential opportunities and challenges. We hope our book chapter will inspire future research on the security and privacy of foundation models.
|
https://arxiv.org/abs/2110.15444v3
|
Sentiment analysis has become a very important tool for analysis of social
media data. There are several methods developed for this research field, many
of them working very differently from each other, covering distinct aspects of
the problem and disparate strategies. Despite the large number of existent
techniques, there is no single one which fits well in all cases or for all data
sources. Supervised approaches may be able to adapt to specific situations but
they require manually labeled training, which is very cumbersome and expensive
to acquire, mainly for a new application. In this context, in here, we propose
to combine several very popular and effective state-of-the-practice sentiment
analysis methods, by means of an unsupervised bootstrapped strategy for
polarity classification. One of our main goals is to reduce the large
variability (lack of stability) of the unsupervised methods across different
domains (datasets). Our solution was thoroughly tested considering thirteen
different datasets in several domains such as opinions, comments, and social
media. The experimental results demonstrate that our combined method (aka,
10SENT) improves the effectiveness of the classification task, but more
importantly, it solves a key problem in the field. It is consistently among the
best methods in many data types, meaning that it can produce the best (or close
to best) results in almost all considered contexts, without any additional
costs (e.g., manual labeling). Our self-learning approach is also very
independent of the base methods, which means that it is highly extensible to
incorporate any new additional method that can be envisioned in the future.
Finally, we also investigate a transfer learning approach for sentiment
analysis as a means to gather additional (unsupervised) information for the
proposed approach and we show the potential of this technique to improve our
results.
|
http://arxiv.org/abs/1711.07915v1
|
This volume contains contributions presented at LLRF2022: the 10th Low-Level RF Workshop held in Brugg-Windisch, Switzerland on October 10-13, 2022.
|
https://arxiv.org/abs/2208.13680v4
|
Can cloud computing infrastructures provide HPC-competitive performance for scientific applications broadly? Despite prolific related literature, this question remains open. Answers are crucial for designing future systems and democratizing high-performance computing. We present a multi-level approach to investigate the performance gap between HPC and cloud computing, isolating different variables that contribute to this gap. Our experiments are divided into (i) hardware and system microbenchmarks and (ii) user application proxies. The results show that today's high-end cloud computing can deliver HPC-competitive performance not only for computationally intensive applications but also for memory- and communication-intensive applications - at least at modest scales - thanks to the high-speed memory systems and interconnects and dedicated batch scheduling now available on some cloud platforms.
|
https://arxiv.org/abs/2011.00656v2
|
Ten years ago, the Mathematics Subject Classification MSC 2010 was released, and a corresponding machine-readable Linked Open Data collection was published using the Simple Knowledge Organization System (SKOS). Now, the new MSC 2020 is out. This paper recaps the last ten years of working on machine-readable MSC data and presents the new machine-readable MSC 2020. We describe the processing required to convert the version of record, as agreed by the editors of zbMATH and Mathematical Reviews, into the Linked Open Data form we call MSC2020-SKOS. The new form includes explicit marking of the changes from 2010 to 2020, some translations of English code descriptions into Chinese, Italian, and Russian, and extra material relating MSC to other mathematics classification efforts. We also outline future potential uses for MSC2020-SKOS in semantic indexing and sketch its embedding in a larger vision of scientific research data.
|
https://arxiv.org/abs/2107.13877v2
|
The Immersion GRating INfrared Spectrometer (IGRINS) is a compact, high-resolution (R~45,000) near-infrared spectrograph spanning 1.45 to 2.45 um in a single exposure. We introduce the Raw and Reduced IGRINS Spectral Archive (RRISA), which provides public data access for all non-proprietary IGRINS data taken at McDonald Observatory's Harlan J. Smith Telescope, the Lowell Discovery Telescope (formerly Discovery Channel Telescope), and Gemini South. RRISA provides access to raw files, reduced data products, and cross-matched IGRINS targets with the SIMBAD, 2MASS, Gaia DR3, APOGEE2 DR17, and PASTEL catalogs. We also introduce version 3 of the IGRINS data reduction pipeline, IGRINS PLP v3, which implements an improved cosmic ray correction, pattern noise removal, and a new flexure correction that reduces telluric residuals. RRISA and supporting information can be found at http://igrinscontact.github.io.
|
https://arxiv.org/abs/2503.05867v1
|
Fair Representation Learning (FRL) is a broad set of techniques, mostly based on neural networks, that seeks to learn new representations of data in which sensitive or undesired information has been removed. Methodologically, FRL was pioneered by Richard Zemel et al. about ten years ago. The basic concepts, objectives and evaluation strategies for FRL methodologies remain unchanged to this day. In this paper, we look back at the first ten years of FRL by i) revisiting its theoretical standing in light of recent work in deep learning theory that shows the hardness of removing information in neural network representations and ii) presenting the results of a massive experimentation (225.000 model fits and 110.000 AutoML fits) we conducted with the objective of improving on the common evaluation scenario for FRL. More specifically, we use automated machine learning (AutoML) to adversarially "mine" sensitive information from supposedly fair representations. Our theoretical and experimental analysis suggests that deterministic, unquantized FRL methodologies have serious issues in removing sensitive information, which is especially troubling as they might seem "fair" at first glance.
|
https://arxiv.org/abs/2407.03834v1
|
The flaring M4 dwarf GJ 1243 has become a benchmark for studying stellar
flare and starspot activity thanks to the exceptional photometric monitoring
archive from the Kepler mission. New light curves from the TESS mission for
this star allow precise stellar activity characterization over more than a
decade timescale. We have carried out the first flare and starspot analysis of
GJ 1243 from over 50 days of data from TESS Sectors 14 and 15. Using 133 flare
events detected in the 2-minute cadence TESS data, we compare the cumulative
flare frequency distributions, and find the flare activity for GJ 1243 is
unchanged between the Kepler and TESS epochs. Two distinct starspot groups are
found in the TESS data, with the primary spot having the same rotational period
and phase as seen in Kepler. The phase of the secondary spot feature is
consistent with the predicted location of the secondary starspot and
measurement of weak differential rotation, suggesting this secondary spot may
be long-lived and stable in both latitude and longitude. As expected for this
highly active star, the constant spot and flare activity reveal no sign of
solar-like activity cycles over 10 years. However, we highlight the unique
ability for Kepler and TESS to use flare rates to detect activity cycles.
|
http://arxiv.org/abs/2005.10281v1
|
As of 2020, the international workshop on Procedural Content Generation enters its second decade. The annual workshop, hosted by the international conference on the Foundations of Digital Games, has collected a corpus of 95 papers published in its first 10 years. This paper provides an overview of the workshop's activities and surveys the prevalent research topics emerging over the years.
|
https://arxiv.org/abs/2104.11037v1
|
A decade ago the archetypal Seyfert-1 galaxy NGC 5548 was discovered to have undergone major spectral changes. The soft X-ray flux had dropped by a factor of 30 while new broad and blueshifted UV absorption lines appeared. This was explained by the emergence of a new obscuring wind from the accretion disk. Here we report on the striking long-term variability of the obscuring disk wind in NGC 5548 including new observations taken in 2021-2022 with the Swift Observatory and the Hubble Space Telescope's (HST) Cosmic Origins Spectrograph (COS). The X-ray spectral hardening as a result of obscuration has declined over the years, reaching its lowest in 2022 at which point we find the broad C IV UV absorption line to be nearly vanished. The associated narrow low-ionization UV absorption lines, produced previously when shielded from the X-rays, are also remarkably diminished in 2022. We find a highly significant correlation between the variabilities of the X-ray hardening and the equivalent width of the broad C IV absorption line, demonstrating that X-ray obscuration is inherently linked to disk winds. We derive for the first time a relation between the X-ray and UV covering fractions of the obscuring wind using its long-term evolution. The diminished X-ray obscuration and UV absorption are likely caused by an increasingly intermittent supply of outflowing streams from the accretion disk. This results in growing gaps and interstices in the clumpy disk wind, thereby reducing its covering fractions.
|
https://arxiv.org/abs/2207.09464v1
|
Abridged - Stars with ZAMS masses between 140 and $260 M_\odot$ are thought to explode as pair-instability supernovae (PISNe). During their thermonuclear runaway, PISNe can produce up to several tens of solar masses of radioactive nickel, resulting in luminous transients similar to some superluminous supernovae (SLSNe). Yet, no unambiguous PISN has been discovered so far. SN2018ibb is a H-poor SLSN at $z=0.166$ that evolves extremely slowly compared to the hundreds of known SLSNe. Between mid 2018 and early 2022, we monitored its photometric and spectroscopic evolution from the UV to the NIR with 2-10m class telescopes. SN2018ibb radiated $>3\times10^{51} \rm erg$ during its evolution, and its bolometric light curve reached $>2\times10^{44} \rm erg\,s^{-1}$ at peak. The long-lasting rise of $>93$ rest-frame days implies a long diffusion time, which requires a very high total ejected mass. The PISN mechanism naturally provides both the energy source ($^{56}$Ni) and the long diffusion time. Theoretical models of PISNe make clear predictions for their photometric and spectroscopic properties. SN2018ibb complies with most tests on the light curves, nebular spectra and host galaxy, potentially all tests with the interpretation we propose. Both the light curve and the spectra require 25-44 $M_\odot$ of freshly nucleosynthesised $^{56}$Ni, pointing to the explosion of a metal-poor star with a He-core mass of 120-130 $M_\odot$ at the time of death. This interpretation is also supported by the tentative detection of [Co II]$\lambda$1.025$\mu$m, which has never been observed in any other PISN candidate or SLSN before. Powering by a central engine, such as a magnetar or a black hole, can be excluded with high confidence. This makes SN2018ibb by far the best candidate for being a PISN, to date.
|
https://arxiv.org/abs/2305.05796v2
|
Unlike, momentum-dependent Rashba spin-splitting, materials exhibiting intrinsic momentum-independent unidirectional spin polarization also known as persistent spin texture (PST) in the full Brillouin zone are scarce. In this work, a list of characteristic electronic properties for identifying an ideal PST material is provided based on earlier analytical models, and a new semiconductor, the MgTe(110) facet is proposed which satisfies all these conditions and exhibits PST in the full Brillouin zone. The atomic arrangement in this particular facet exhibits three basic symmetries found in nature: rotation, reflection, and translation. Using the method of invariance, an effective Hamiltonian is constructed which reproduces the results obtained using the density functional theory. Further, mono/few layers of MgTe (110) facets of the zinc-blende structure are proposed for a ferromagnet-free non-ballistic spin-field effect transistor (s-FET) that combines both the spin-Hall effect and inverse spin-Hall effect, thus harmonizing spintronics with conventional electronics. Although only quantum well structures have been experimentally studied for nonballistic s-FET under the stringent condition of equal Rashba and Dresselhaus strength, PST originating intrinsically in the proposed 2D structures makes them an ideal alternate.
|
https://arxiv.org/abs/2309.10868v3
|
High bandwidth, low voltage electro-optic modulators with high optical power handling capability are important for improving the performance of analog optical communications and RF photonic links. Here we designed and fabricated a thin-film lithium niobate (LN) Mach-Zehnder modulator (MZM) which can handle high optical power of 110 mW, while having 3-dB bandwidth greater than 110 GHz at 1550 nm. The design does not require etching of thin-film LN, and uses hybrid optical modes formed by bonding LN to planarized silicon photonic waveguide circuits. A high optical power handling capability in the MZM was achieved by carefully tapering the underlying Si waveguide to reduce the impact of optically-generated carriers, while retaining a high modulation efficiency. The MZM has a $V_\pi L$ product of 3.1 V.cm and an on-chip optical insertion loss of 1.8 dB.
|
https://arxiv.org/abs/2210.14785v1
|
Integrated thin film lithium niobate (TFLN) modulators are emerging as an appealing solution to high-speed data processing and transmission due to their high modulation speed and low driving voltage. The key step in fabricating integrated TFLN modulators is the high-quality etching of TFLN, which typically requires long-term optimization of fabrication recipe and specialized equipment. Here we present an integrated TFLN modulator by incorporating low-index rib loaded waveguides onto TFLN without direct etching of TFLN. Based on our systematic investigation into the theory and design methodology of the proposed design, we experimentally demonstrated a TFLN etching-free Mach-Zehnder modulator, featuring a flat electro-optic response up to 110 GHz and a voltage-length product of 2.53 V cm. By significantly simplifying the fabrication process, our design opens up new ways of mass production of high-speed integrated TFLN modulators at low cost.
|
https://arxiv.org/abs/2308.03073v4
|
A compact Kerr-lens mode-locked thin-disk oscillator delivering 110 MW output peak power, the highest among all oscillators, is reported. A pulse train with a repetition rate of 14 MHz carries 115 fs long, 14.4 uJ pulses resulting in 202 W of average power. This compact, simple, and stable oscillator is a suitable driver and an important milestone for further high harmonics generation and the development of extreme ultraviolet transportable frequency comb sources.
|
https://arxiv.org/abs/2204.03384v2
|
Spinterface engineering has shown quite important roles in organic
spintronics as it can improve spin injection or extraction. In this study,
11,11,12,12-tetracyanonaptho-2,6-quinodimethane (TNAP) is introduced as an
interfacial layer for a prototype interface of Fe/TNAP. We report an
element-specific investigation of the electronic and magnetic structures of
Fe/TNAP system by use of near edge X-Ray absorption fine structure (NEXAFS) and
X-ray magnetic circular dichroism (XMCD). Strong hybridization between TNAP and
Fe and induced magnetization of N atoms in TNAP molecule are observed. XMCD sum
rule analysis demonstrates that the adsorption of TNAP reduces the spin moment
of Fe by 12%. In addition, induced magnetization in N K-edge of TNAP has also
been found with other commonly used ferromagnets in organic spintronics, such
as La0.7Sr0.3MnO3 and permalloy, which makes TNAP a very promising molecule for
spinterface engineering in organic spintronics.
|
http://arxiv.org/abs/1805.07906v1
|
We report the (111) facet-engineered cubic phase SnO2 (C-SnO2) as a novel electron transport layer (ETL) for triple-cation mixed-halide Cs0.05(FA0.83MA0.17)0.95Pb(I0.83Br0.17)3 perovskite solar cells (PSCs). The C-SnO2 layer was prepared via a normal sol-gel process followed by the spin-coating technique. The (111) facet C-SnO2 layer provides a larger surface contact area with an adjacent perovskite layer, enhancing charge transfer dynamics at the interface. In addition, the well-matched overlapping band structures improve the charge extraction efficiency between the two layers. Using (111) facet C-SnO2 as ETLs, we obtain PSCs with a higher power conversion efficiency of 20.34% (0.09 cm2) than those employing tetragonal phase SnO2 ETL. The PSCs with C-SnO2 ETL retain over 81% of their initial efficiency even after 480 h. This work concludes with a brief discussion on recombination and charge transport mechanisms, providing ways to optimize C-SnO2 ETL to improve the PSCs' performance and stability.
|
https://arxiv.org/abs/2502.15327v1
|
We present an implementation of all-diamond scanning probes for scanning
nitrogen-vacancy (NV) magnetometry fabricated from (111)-oriented diamond
material. The realized scanning probe tips on average contain single NV spins,
a quarter of which have their spin quantization axis aligned parallel to the
tip direction. Such tips enable single-axis vector magnetic field imaging with
nanoscale resolution, where the measurement axis is oriented normal to the scan
plane. We discuss how these tips bring multiple practical advantages for NV
magnetometry, in particular regarding quantitative analysis of the resulting
data. We further demonstrate the beneficial optical properties of NVs oriented
along the tip direction, such as polarization-insensitive excitation, which
simplifies optical setups needed for NV magnetometry. Our results will be
impactful for scanning NV magnetometry in general and for applications in
spintronics and the investigation of thin film magnets in particular.
|
http://arxiv.org/abs/1910.10733v2
|
(001) Si spin qubits are being intensively studied because they have structures similar to that of CMOS devices currently being produced, and thus have the advantage of utilizing state-of-the-art miniaturization, integration, and variation-reduction-technologies. However, there are still issues, such as further improvement of relaxation and decoherence time, stabilization of valley-splitting control, and reduction of the variation caused by the roughness of the interface. In this study, new measures are proposed to address these three issues. Instead of confining an electron to the minimum energy point $X_0$ of the conduction band along the band structure $\Gamma-\Delta-X$ in (001) Si crystals, we propose confining an electron to the L point along $\Gamma-\Lambda-L$ in (111) Si crystals. At the $X_0$ point, the symmetry causes spin-orbit interaction to act on the electron, and the sixfold degeneracy is lifted into a fourfold and a twofold, and the valley-splitting of the twofold conflicts with the two-level system. In the symmetry of the $L$ point, substantial spin polarization disappears, facilitating the reduction of the spin-orbit interaction, and the fourfold degeneracy is lifted to threefold and single, and the single becomes ground state. The need to increase the magnitude of the valley-splitting is exempt, allowing the electron to be controlled away from the interface, which is expected to reduce the variation caused by the roughness of the interface. Data on the confinement of an electron to the $L$ point and the control of fourfold degeneracy are needed, and it is hoped that prototype silicon spin qubits constructed on (111) Si crystals will be developed and that the proposed device structure will help implement quantum computers based on Si devices.
|
https://arxiv.org/abs/2501.13546v1
|
We study classical spin ice under uniaxial strain along the $[111]$ crystallographic axis. Remarkably, such strain preserves the extensive ice degeneracy and the corresponding classical Coulomb phase. The emergent monopole excitations remain thermodynamically deconfined exactly as in the isotropic case. However, their motion under local heat bath dynamics depends qualitatively on the sign of the strain. In the low-temperature limit for negative strain, the monopoles diffuse, while for positive strain, they localize. Introducing additional ring exchange dynamics into the ice background transforms the localized monopoles into sub-dimensional excitations whose motion is restricted to diffusion in the $(111)$-plane. The phenomena we identify are experimentally accessible in rare-earth pyrochlores under uniaxial pressure as well as in tripod kagome materials. The diffusive versus localized nature of the monopoles manifests in characteristic magnetic noise spectra, which we compute.
|
https://arxiv.org/abs/2406.18649v2
|
Large Language Models (LLMs) have garnered significant attention due to their remarkable ability to process information across various languages. Despite their capabilities, they exhibit inconsistencies in handling identical queries in different languages, presenting challenges for further advancement. This paper introduces a method to enhance the multilingual performance of LLMs by aggregating knowledge from diverse languages. This approach incorporates a low-resource knowledge detector specific to a language, a language selection process, and mechanisms for answer replacement and integration. Our experiments demonstrate notable performance improvements, particularly in reducing language performance disparity. An ablation study confirms that each component of our method significantly contributes to these enhancements. This research highlights the inherent potential of LLMs to harmonize multilingual capabilities and offers valuable insights for further exploration.
|
https://arxiv.org/abs/2406.14721v1
|
A lattice is $(1+1+2)$-generated if it has a four-element generating set such that exactly two of the four generators are comparable. We prove that the lattice Quo$(n)$ of all quasiorders (also known as preorders) of an $n$-element set is $(1+1+2)$-generated for $n=3$ (trivially), $n=6$ (when Quo(6) consists of $209\,527$ elements), n=11, and for every natural number $n\geq 13$. In 2017, the second author and J. Kulin proved that Quo$(n)$ is $(1+1+2)$-generated if either $n$ is odd and at least $13$ or $n$ is even and at least $56$. Compared to the 2017 result, this paper presents twenty-four new numbers $n$ such that Quo$(n)$ is $(1+1+2)$-generated. Except for Quo(6), an extension of Z\'adori's method is used.
|
https://arxiv.org/abs/2104.14653v1
|
Software programming requires both API reference (know-what) knowledge and programming task (know-how) knowledge. Lots of programming know-what and know-how knowledge is documented in text, for example, API reference documentation and programming tutorials. To improve knowledge accessibility and usage, several recent studies use Natural Language Processing (NLP) methods to construct API know-what knowledge graph (API-KG) and programming task know-how knowledge graph (Task-KG) from software documentation. Although being promising, current API-KG and Task-KG are independent of each other, and thus are void of inherent connections between the two types of knowledge. Our empirical study on Stack Overflow questions confirms that only 36% of the API usage problems can be answered by the know-how or the know-what knowledge alone, while the rest questions require a fusion of both. Inspired by this observation, we make the first attempt to fuse API-KG and Task-KG by API entity linking. This fusion creates nine categories of API semantic relations and two types of task semantic relations which are not present in the stand-alone API-KG or Task-KG. According to the definitions of these new API and task semantic relations, our approach dives deeper than the surface-level API linking of API-KG and Task-KG, and infers nine categories of API semantic relations from task descriptions and two types of task semantic relations with the assistance of API-KG, which enrich the declaration or syntactic relations in the current API-KG and Task-KG. Our fused and semantically-enriched API-Task KG supports coherent API/Task-centric knowledge search by text or code queries.
|
https://arxiv.org/abs/2207.05560v3
|
In 1910, Hendrik Antoon Lorentz delved into the enigmatic Laplace eigenvalue equation, also known as the Helmholtz equation, pondering to what extent the geometry in which one solves the equation can be recovered from knowledge of the eigenvalues. Lorentz, inspired by physical and musical analogies, conjectured a fundamental relationship between eigenvalues, domain volume, and dimensionality. While his conjecture initially seemed insurmountable, Hermann Weyl's groundbreaking proof in 1912 illuminated the deep connection between eigenvalues and geometric properties. Over the ensuing 112 years, mathematicians and physicists have continued to decipher the intricate interplay between eigenvalues and geometry. From Weyl's law to Milnor's example of isospectral non-isometric flat tori, and Kac's inspiring question about hearing the shape of a drum, the field has witnessed remarkable progress, uncovering spectral invariants and advancing our understanding of geometric properties discernible through eigenvalues. We present an overview of this field amenable to both physicists and mathematicians.
|
https://arxiv.org/abs/2406.18369v2
|
We present an alternative analysis of the $^{113}$Cd $\beta$-decay electron energy spectrum in terms of spectral moments $\mu_n$, corresponding to the averaged values of $n^{\rm th}$ powers of the $\beta$ particle energy. The zeroth moment $\mu_0$ is related to the decay rate, while higher moments $\mu_n$ are related to the spectrum shape. The here advocated spectral-moment method (SMM) allows for a complementary understanding of previous results, obtained using the so-called spectrum-shape method (SSM) and its revised version, in terms of two free parameters: $r=g_{\rm A}/g_{\rm V}$ (the ratio of axial-vector to vector couplings) and $s$ (the small vector-like relativistic nuclear matrix element, $s$-NME). We present numerical results for three different nuclear models with the conserved vector current hypothesis (CVC) assumption of $g_{\rm V}=1$. We show that most of the spectral information can be captured by the first few moments which are simple quadratic forms (conic sections) in the $(r,\,s)$ plane: an ellipse for $n=0$ and hyperbolae for $n\geq 1$, all being nearly degenerate as a result of cancellations among nuclear matrix elements. The intersections of these curves, as obtained by equating theoretical and experimental values of $\mu_n$, identify the favored values of $(r,\,s)$ at a glance, without performing detailed fits. In particular, we find that values around $r\sim 1$ and $s\sim 1.6$ are consistently favored in each nuclear model, confirming the evidence for $g_{\rm A}$ quenching in $^{113}$Cd, and shedding light on the role of the $s$-NME. We briefly discuss future applications of the SMM to other forbidden $\beta$-decay spectra sensitive to $g_{\rm A}$.
|
https://arxiv.org/abs/2302.07048v2
|
Accurate long-distance ranging is crucial for diverse applications, including satellite formation flying, very-long-baseline interferometry, gravitational-wave observatory, geographical research, etc. The integration of the time-of-flight mesurement with phase interference in dual-comb method enables high-precision ranging with a rapid update rate and an extended ambiguity range. Pioneering experiments have demonstrated unprecedented precision in ranging, achieving 5 nm @ 60 ms for 1.1 m and 200 nm @ 0.5 s for 25 m. However, long-distance ranging remains technically challenging due to high transmission loss and noise. In this letter, we propose a two-way dual-comb ranging (TWDCR) approach that enables successful ranging over a distance of 113 kilometers. We employ air dispersion analysis and synthetic repetition rate technique to extend the ambiguity range of the inherently noisy channel beyond 100 km. The achieved ranging precision is 11.5 $\mu$m @ 1.3 ms, 681 nm @ 1 s, and 82 nm @ 21 s, as confirmed through a comparative analysis of two independent systems. The advanced long-distance ranging technology is expected to have immediate implications for space research initiatives, such as the space telescope array and the satellite gravimetry.
|
https://arxiv.org/abs/2412.05542v1
|
Optical clock networks play important roles in various fields, such as precise navigation, redefinition of "second" unit, and gravitational tests. To establish a global-scale optical clock network, it is essential to disseminate time and frequency with a stability of $10^{-19}$ over a long-distance free-space link. However, such attempts were limited to dozens of kilometers in mirror-folded configuration. Here, we take a crucial step toward future satellite-based time-frequency disseminations. By developing the key technologies, including high-power frequency combs, high-stability and high-efficiency optical transceiver systems, and efficient linear optical sampling, we demonstrate free-space time-frequency dissemination over two independent links with femtosecond time deviation, $3\times10^{-19}$ at 10,000 s residual instability and $1.6\times10^{-20}\pm 4.3\times10^{-19}$ offset. This level of the stability retains for an increased channel loss up to 89 dB. Our work can not only be directly used in ground-based application, but also firmly laid the groundwork for future satellite time-frequency dissemination.
|
https://arxiv.org/abs/2203.11272v1
|
We prove that up to two exceptions, every connected subcubic triangle-free graph has fractional chromatic number at most 11/4. This is tight unless further exceptional graphs are excluded, and improves the known bound on the fractional chromatic number of subcubic triangle-free planar graphs.
|
https://arxiv.org/abs/2204.12683v3
|
Knowledge of the past behavior of Antarctic polynyas such as the Ross and
Weddell Seas contributes to the understanding of biological productivity, sea
ice production, katabatic and Southern Hemisphere Westerly (SHW) wind strength,
Antarctic bottom water (ABW) formation, and marine CO2 sequestration. Previous
studies link barium (Ba) marine sedimentation to polynya primary productivity
(Bonn et al., 1998; McManus et al., 2002; Pirrung et al., 2008), polynya area
to katabatic wind strength and proximal cyclones (Bromwich et al., 1998;
Drucker et al., 2011), and highlight the influence of Ross Ice Shelf calving
event effects on the Ross Sea Polynya (RSP) (Rhodes et al., 2009). Here we use
the RICE ice core, located just 120 km from the Ross Ice Shelf front to capture
1150 years of RSP behavior. We link atmospheric Ba fluctuations to Ba marine
sedimentation in the summer Ross Sea Polynya, creating the first deep ice core
based RSP proxy. RSP area is currently the smallest ever observed over our
1150-year record, and varied throughout the Little Ice Age with fluctuations in
Amundsen Sea Low (ASL) strength related with Ross Sea cyclones. Past RSP
reconstructions allow us to predict future responses of RSP area to future
climate change, which is of special interest considering the recent
disappearance of the Weddell Sea Polynya in response to anthropogenic forcing
(de Lavergne et al., 2014).
|
http://arxiv.org/abs/2006.01093v1
|
We present a scalable mixed-species Coulomb crystal clock based on the $^1S_0$ $\leftrightarrow$ $^3P_0$ transition in $^{115}$In$^+$. $^{172}$Yb$^+$ ions are co-trapped and used for sympathetic cooling. Reproducible interrogation conditions for mixed-species Coulomb crystals are ensured by a conditional preparation sequence with permutation control. We demonstrate clock operation with a 1In$^+$-3Yb$^+$ crystal, achieving a relative systematic uncertainty of $2.5\times10^{-18}$ and a relative frequency instability of $1.6\times10^{-15}/\sqrt{\tau/1\;\mathrm{s}}$. We report on absolute frequency measurements with an uncertainty of $1.3\times10^{-16}$ and optical frequency comparisons with clocks based on $^{171}$Yb$^+$ (E3) and $^{87}$Sr. With a fractional uncertainty of $4.4\times10^{-18}$, the former is - to our knowledge - the most accurate frequency ratio value reported to date. For the $^{115}$In$^+$/$^{87}$Sr ratio, we improve upon the best previous measurement by more than an order of magnitude. We also demonstrate operation with four $^{115}$In$^+$ clock ions, which reduces the instability to $9.2\times10^{-16}/\sqrt{\tau/1\;\mathrm{s}}$.
|
https://arxiv.org/abs/2402.16807v3
|
Using a novel geometrically-shaped four-dimensional modulation format, we
transmitted 11x200 Gbit/s DWDM at 4.8 bit/4D-sym over 7,925 km and 11,700 km
using EDFA-only and hybrid amplification, respectively. A reach increase of 16%
is achieved over PM-8QAM.
|
http://arxiv.org/abs/1904.12561v1
|
We give a diagrammatic characterization of the $(1,1)$ knots in the three-sphere and lens spaces which admit large Dehn surgeries to manifolds with Heegaard Floer homology of next-to-minimal rank. This is inspired by a corresponding result for $(1,1)$ knots which admit large Dehn surgeries to manifolds with Heegaard Floer homology of minimal rank due to Greene-Lewallen-Vafaee.
|
https://arxiv.org/abs/2304.11475v1
|
The resonance region of $^{11}$B covering excitation energies from 8.4 MeV to 13.6 MeV was investigated with the $(d,p)$ reaction performed on an enriched $^{10}$B target at the Florida State University Super-Enge Split-Pole Spectrograph of the John D. Fox Superconducting Linear Accelerator Laboratory. Complementary measurements were performed with a target enriched in $^{11}$B to identify possible $^{12}$B contaminants in the $(d,p)$ reaction. Four strongly populated $^{11}$B states were observed above the $\alpha$-decay threshold. Angular distributions were measured and compared to DWBA calculations to extract angular momentum transfers and $^{10}\mathrm{B}\left(3^+\right)+n$ spectroscopic factors. The recently observed and heavily discussed resonance at 11.4 MeV in $^{11}$B was not observed in this work. This result is consistent with the interpretation that it is predominantly a $^{10}\mathrm{Be}\left(0^+\right)+p$ resonance with a possible additional $^{7}\mathrm{Li}+\alpha$ contribution. The predicted $^{10}\mathrm{B}\left(3^+\right)+n$ resonance at 11.6 MeV, analogous to the 11.4-MeV proton resonance, was not observed either. Upper limits for the $^{10}\mathrm{B}\left(3^+\right)+n$ spectroscopic factors of the 11.4-MeV and 11.6-MeV states were determined. In addition, supporting configuration interaction shell model calculations with the effective WBP interaction are presented.
|
https://arxiv.org/abs/2411.09831v1
|
A graph $H$ is a clique graph if $H$ is a vertex-disjoin union of cliques. Abu-Khzam (2017) introduced the $(a,d)$-{Cluster Editing} problem, where for fixed natural numbers $a,d$, given a graph $G$ and vertex-weights $a^*:\ V(G)\rightarrow \{0,1,\dots, a\}$ and $d^*{}:\ V(G)\rightarrow \{0,1,\dots, d\}$, we are to decide whether $G$ can be turned into a cluster graph by deleting at most $d^*(v)$ edges incident to every $v\in V(G)$ and adding at most $a^*(v)$ edges incident to every $v\in V(G)$. Results by Komusiewicz and Uhlmann (2012) and Abu-Khzam (2017) provided a dichotomy of complexity (in P or NP-complete) of $(a,d)$-{Cluster Editing} for all pairs $a,d$ apart from $a=d=1.$ Abu-Khzam (2017) conjectured that $(1,1)$-{Cluster Editing} is in P. We resolve Abu-Khzam's conjecture in affirmative by (i) providing a serious of five polynomial-time reductions to $C_3$-free and $C_4$-free graphs of maximum degree at most 3, and (ii) designing a polynomial-time algorithm for solving $(1,1)$-{Cluster Editing} on $C_3$-free and $C_4$-free graphs of maximum degree at most 3.
|
https://arxiv.org/abs/2210.07722v2
|
The covariance matrix adaptation evolution strategy (CMA-ES) is an efficient continuous black-box optimization method. The CMA-ES possesses many attractive features, including invariance properties and a well-tuned default hyperparameter setting. Moreover, several components to specialize the CMA-ES have been proposed, such as noise handling and constraint handling. To utilize these advantages in mixed-integer optimization problems, the CMA-ES with margin has been proposed. The CMA-ES with margin prevents the premature convergence of discrete variables by the margin correction, in which the distribution parameters are modified to leave the generation probability for changing the discrete variable. The margin correction has been applied to ($\mu/\mu_\mathrm{w}$,$\lambda$)-CMA-ES, while this paper introduces the margin correction into (1+1)-CMA-ES, an elitist version of CMA-ES. The (1+1)-CMA-ES is often advantageous for unimodal functions and can be computationally less expensive. To tackle the performance deterioration on mixed-integer optimization, we use the discretized elitist solution as the mean of the sampling distribution and modify the margin correction not to move the elitist solution. The numerical simulation using benchmark functions on mixed-integer, integer, and binary domains shows that (1+1)-CMA-ES with margin outperforms the CMA-ES with margin and is better than or comparable with several specialized methods to a particular search domain.
|
https://arxiv.org/abs/2305.00849v1
|
We prove that any $11$-colorable knot is presented by an $11$-colored diagram
where exactly five colors of eleven are assigned to the arcs. The number five
is the minimum for all non-trivially $11$-colored diagrams of the knot. We also
prove a similar result for any $11$-colorable ribbon $2$-knot.
|
http://arxiv.org/abs/1505.02980v1
|
We analyze how pre-existing entanglement between two Unruh-DeWitt particle
detectors evolves when one of the detectors falls through a Rindler firewall in
(1+1)-dimensional Minkowski space. The firewall effect is minor and does not
wash out the detector-detector entanglement, in some regimes even preserving
the entanglement better than Minkowski vacuum. The absence of cataclysmic
events should continue to hold for young black hole firewalls. A firewall's
prospective ability to resolve the information paradox must hence hinge on its
detailed gravitational structure, presently poorly understood.
|
http://arxiv.org/abs/1502.07749v2
|
We use a variational method to calculate the spectrum and the parton distribution function of ground state hadrons of various gauge theories in 1+1 dimensions. The template functions in our method minimize a free energy functional defined as a combination of free valence partons' kinetic energy on the lightcone and the Renyi entanglement entropy of biparton subsystems. Our results show that hadrons in these theories minimize the proposed free energy. The success of this technique motivates applying it to confining gauge theories in higher dimensions.
|
https://arxiv.org/abs/2301.03611v1
|
$1+1$-dimensional Dirac oscillator with minimal uncertainty in position and
maximal in momentum is investigated. To obtain energy spectrum SUSY QM
technique is applied. It is shown that the Dirac oscillator has two branches of
spectrum, the first one gives the standard spectrum of the Dirac oscillator
when the parameter of deformation goes to zero and the second branch does not
have nondeformed limit. Maximal momentum brings an upper bound for the energy
and it gives rise to the conclusion that the energy spectrum contains a finite
number of eigenvalues. We also calculate partition function for the spectrum of
the first type. The partition function allows us to derive thermodynamic
functions of the oscillator which are obtained numerically.
|
http://arxiv.org/abs/1810.00056v1
|
We introduce a four-dimensional extension of the Poincar\'{e} algebra
$(\mathcal{N})$ in (1+1)-dimensional space-time and obtain a (1+1)-dimensional
gauge symmetric gravity model using the algebra $\mathcal{N}$. We show that the
obtained gravity model is dual (canonically transformed) to the
(1+1)-dimensional anti de Sitter ($AdS$) gravity. We also obtain some black
hole and Friedmann-Robertson-Walker (FRW) solutions by solving its classical
equations of motion. Then, we study
$\frac{\mathbf{A}_{\mathbf{4,8}}}{\mathbf{A}_{\mathbf{1}}\otimes
\mathbf{A}_{\mathbf{1}}}$ gauged Wess-Zumino-Witten (WZW) model and obtain some
exact black hole and cosmological solutions in string theory. We show that some
obtained black hole and cosmological metrics in string theory are same as the
metrics obtained in solutions of our gauge symmetric gravity model.
|
http://arxiv.org/abs/1704.04634v2
|
We study 1+1 dimensional relativistic non-resistive magnetohydrodynamics (MHD) with longitudinal boost invariance and shear stress tensor. Several analytical solutions that describe the fluid temperature evolution under the equation of state (EoS) $\varepsilon=3p$ are derived, relevant to relativistic heavy-ion collisions. Extending the Victor-Bjorken ideal MHD flow to include non-zero shear viscosity, two perturbative analytical solutions for the first-order (Navier-Stokes) approximation are obtained. For small, power-law evolving external magnetic fields, our solutions are stable and show that both magnetic field and shear viscosity cause fluid heating with an early temperature peak, align with the numerical results. In the second-order (Israel-Stewart) theory, our findings show that the combined presence of magnetic field and shear viscosity leads to a slow cooling rate of fluid temperature, with initial shear stress significantly affecting temperature evolution of QGP.
|
https://arxiv.org/abs/2411.11398v1
|
We study scalar field theory in one space and one time dimensions on a q-deformed space with static background. We write the Lagrangian and the equation of motion and solve it to the first order in $q-1$ where $q$ is the deformation parameter of the space.
|
https://arxiv.org/abs/2301.03106v1
|
We present an implicit numerical method to solve the time-dependent equations
of radiation hydrodynamics (RHD) in axial symmetry assuming hydrostatic
equilibrium perpendicular to the equatorial plane (1+1D) of a gaseous disk. The
equations are formulated in conservative form on an adaptive grid and the
corresponding fluxes are calculated by a spacial second order advection scheme.
Self-gravity of the disk is included by solving the Possion equation. We test
the resulting numerical method through comparison with a simplified analytical
solution as well as through the long term viscous evolution of protoplanetary
disk when due to viscosity matter is transported towards the central host star
and the disk depletes. The importance of the inner boundary conditions on the
structural behaviour of disks is demonstrated with several examples.
|
http://arxiv.org/abs/2006.12939v1
|
To investigate1,1-Diphenyl-2-picrylhydrazyl (DPPH) and superoxide radical (SOR) 17 scavenging activities of 2-oxo-1,2,3,4-tetrahydropyrimidines derivatives. Free radicals are 18 highly unstable and reactive molecules/atoms. In the body, free radicals form during 19 normal and abnormal metabolism in the body and cause serious damage to other 20 biomolecules through generating oxidative stress (OS). If free radicals induced OS does 21 not neutralized properly, host multiple pathologies including several types of cancers.
|
https://arxiv.org/abs/2310.10063v1
|
We consider symmetry protected topological (SPT) phases with finite non-invertible symmetry $\mathcal{C}$ in 1+1d. In particular, we investigate interfaces and parameterized families of them within the framework of matrix product states. After revealing how to extract the $\mathcal{C}$-SPT invariant, we identify the algebraic structure of symmetry operators acting on the interface of two $\mathcal{C}$-SPT phases. By studying the representation theory of this algebra, we show that there must be a degenerate interface mode between different $\mathcal{C}$-SPT phases. This result generalizes the bulk-boundary correspondence for ordinary SPT phases. We then propose the classification of one-parameter families of $\mathcal{C}$-SPT states based on the explicit construction of invariants of such families. Our invariant is identified with a non-abelian generalization of the Thouless charge pump, which is the pump of a local excitation within a $\mathcal{C}$-SPT phase. Finally, by generalizing the results for one-parameter families of SPT phases, we conjecture the classification of general parameterized families of general gapped phases with finite non-invertible symmetries in both 1+1d and higher dimensions.
|
https://arxiv.org/abs/2408.15960v1
|
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