Hasil untuk "Geophysics. Cosmic physics"

N. Bartolo, E. Komatsu, S. Matarrese et al.

This is a review of models of inflation and of their predictions for the primordial non-Gaussianity in the density perturbations which are thought to be at the origin of structures in the Universe. Non-Gaussianity emerges as a key observable to discriminate among competing scenarios for the generation of cosmological perturbations and is one of the primary targets of present and future Cosmic Microwave Background satellite missions. We give a detailed presentation of the state-of-the-art of the subject of non-Gaussianity, both from the theoretical and the observational point of view, and provide all the tools necessary to compute at second order in perturbation theory the level of non-Gaussianity in any model of cosmological perturbations. We discuss the new wave of models of inflation, which are firmly rooted in modern particle physics theory and predict a significant amount of non-Gaussianity. The review is addressed to both astrophysicists and particle physicists and contains useful tables which summarize the theoretical and observational results regarding non-Gaussianity.

M. Ishak

We review recent developments and results in testing general relativity (GR) at cosmological scales. The subject has witnessed rapid growth during the last two decades with the aim of addressing the question of cosmic acceleration and the dark energy associated with it. However, with the advent of precision cosmology, it has also become a well-motivated endeavor by itself to test gravitational physics at cosmic scales. We overview cosmological probes of gravity, formalisms and parameterizations for testing deviations from GR at cosmological scales, selected modified gravity (MG) theories, gravitational screening mechanisms, and computer codes developed for these tests. We then provide summaries of recent cosmological constraints on MG parameters and selected MG models. We supplement these cosmological constraints with a summary of implications from the recent binary neutron star merger event. Next, we summarize some results on MG parameter forecasts with and without astrophysical systematics that will dominate the uncertainties. The review aims at providing an overall picture of the subject and an entry point to students and researchers interested in joining the field. It can also serve as a quick reference to recent results and constraints on testing gravity at cosmological scales.

K. Bongs, M. Holynski, J. Vovrosh et al.

M. Volonteri, M. Habouzit, M. Colpi

Massive black holes (MBHs) inhabit galactic centres, and power luminous quasars and active galactic nuclei, shaping their cosmic environment with the energy they produce. The origins of MBHs remain a mystery, and the recent detection by LIGO/Virgo of a black hole of almost 150 solar masses has revitalized the questions of whether there is a continuum between ‘stellar’ and ‘massive’ black holes, and what the seeds of MBHs are. Seeds could have formed in the first galaxies or could be related to the collapse of horizon-sized regions in the early Universe. Understanding the origins of MBHs straddles fundamental physics, cosmology and astrophysics, and bridges the fields of gravitational-wave physics and traditional astronomy. With several existing and upcoming facilities in the next 10–15 years, we foresee the possibility of discovering the avenues of formation of MBHs. This Review links three main topics: the channels of black hole seed formation, the journey from seeds to MBHs, and the diagnostics on the origins of MBHs. We highlight and critically discuss current unsolved problems, touching on recent developments. Massive black holes dwell in many galaxies, and various physical processes have been invoked to explain their presence. This Review discusses their formation channels, how they have grown over time from smaller seeds and how we can constrain their origins. The discoveries of quasars at cosmic distances and of giant dark massive objects in today’s galaxies provide evidence of the ubiquity of massive black holes (MBHs). Understanding the origins of MBHs goes hand in hand with understanding the origins of the structures inside the cosmic web. MBHs are not born ‘massive’ but must have grown by several orders of magnitude from ‘seed black holes’. Gas accretion and black hole mergers are the drivers of their growth inside galaxies, but there are several bottlenecks in this journey. The origins of MBHs may be from exotic mechanisms or may well lie in known physics — particle, plasma and condensed matter physics, gravity and dynamics — extrapolated to untested regimes. Studying the origins of MBHs is a multi-scale problem: from the Schwarzschild radius to cosmological scales, from subsecond events to the age of the Universe. Paths to seed formation and growth are not mutually exclusive. Constraints will therefore come from a combination of observables: masses, spins, distances, spectra and light curves of populations of black holes. These indirect constraints can confirm that a given path exists but cannot rule out the existence of other paths. A combination of electromagnetic and gravitational-wave observations is the foreseen best strategy to constrain the origins of MBHs. The discoveries of quasars at cosmic distances and of giant dark massive objects in today’s galaxies provide evidence of the ubiquity of massive black holes (MBHs). Understanding the origins of MBHs goes hand in hand with understanding the origins of the structures inside the cosmic web. MBHs are not born ‘massive’ but must have grown by several orders of magnitude from ‘seed black holes’. Gas accretion and black hole mergers are the drivers of their growth inside galaxies, but there are several bottlenecks in this journey. The origins of MBHs may be from exotic mechanisms or may well lie in known physics — particle, plasma and condensed matter physics, gravity and dynamics — extrapolated to untested regimes. Studying the origins of MBHs is a multi-scale problem: from the Schwarzschild radius to cosmological scales, from subsecond events to the age of the Universe. Paths to seed formation and growth are not mutually exclusive. Constraints will therefore come from a combination of observables: masses, spins, distances, spectra and light curves of populations of black holes. These indirect constraints can confirm that a given path exists but cannot rule out the existence of other paths. A combination of electromagnetic and gravitational-wave observations is the foreseen best strategy to constrain the origins of MBHs.

Deepanjan Majumdar

Abstract In a first instance for India, annual mean ambient PM10 concentrations in 209 Indian cities, estimated from National Air Quality Monitoring Program (NAMP) database of India (2012−2021), were deployed in a structured DataFrame to simulate PM10 clubs of cities by Philips and Sul’s Club Convergence algorithm. Four PM10 clubs (Club 1: 26, Club 2: 63; Club 3: 103 and Club 4: 17 cities) were identified. Club 1 with highest ambient PM10 (decadal mean and range: 182 and 75.0−329.0 µg m− 3, respectively) had 92.3% non-attainment cities while 83.4% are inside Indo-Gangetic Plain (IGP), the most polluted region in India. Further, 71.4% cities in second-most polluted Club 2 (decadal mean and range: 114.52 and 34.0−267.7 µg m− 3, respectively), are non-attainment cities in which 28.6% cities are located inside IGP. Non-attainment cities together have a share of 48.5% in Club 3 (decadal mean and range: 75.91 and 25−329 µg m− 3, respectively) and only 4.9% are inside IGP. The cities in Club 4 with lowest ambient PM10 levels (decadal mean and range: 41.62 and 8.5−109 µg m− 3, respectively) are either located on or near coastal areas that come under the influence of land and sea breeze or in North-Eastern hilly region, characterized by low population density and limited anthropogenic and industrial activities. PM10 clubs underscore the influence of geographical location and extent of regional development on ambient PM10 pollution and the potential need for formulation of club-specific air quality management practices in India.

Yuqing Liu, Zhubin Zheng, Jianzhong Li et al.

Overexploitation of rare Earth mining areas in southern Jiangxi Province has caused severe vegetation degradation. However, the impact of vegetation restoration on ecosystem services (ESs) and their interactions in rare Earth mining areas remains underexplored. This study uses vegetation coverage (FVC) as an indicator to assess vegetation changes in rare Earth mining areas from 1986 to 2020. The integrated assessment of ESs and tradeoffs (InVEST) and the Carnegie-arms-stanford method model were applied to assess soil conservation, carbon storage, water retention, and purification services in the study area from 1990 to 2020, while analyzing the spatiotemporal evolution of ESs. Finally, the eXtreme Gradient Boosting model was used to construct the regional total ecosystem services (RTES) index, analyzing the threshold effect between ESs and FVC. The results reveal that: 1) From 1986 to 2020, vegetation coverage in rare Earth mining areas exhibited a fluctuating upward trend, with significant increases occurring in 40.14% of the study area; 2) ESs declined significantly overall; 3) Increased vegetation coverage improved the regional ecological environment to some extent, though this improvement was constrained by a threshold effect. To optimize RTES, vegetation coverage in the Gannan rare Earth mining areas should range between 0.6 and 0.7. This study offers a theoretical foundation for large-scale ecological management and moderate restoration of rare Earth mining areas, supporting regional sustainable development. It also underscores the need for the public and managers to recognize the impact of vegetation restoration on ecosystem functions in rare Earth mining areas.

Changsheng OuYang, Hui Li

As is known, the accurate extraction of buildings from high-resolution remote sensing images has become a pivotal objective. In some complex scenes (e.g., there will be objects with a similar spectral texture to buildings in the image, trees and shadows will obscure the buildings, etc.), the existing models cannot accurately recognize the buildings. To address this series of challenges, we propose a new method, BuildNext-Net, which consists of TransNext-EMAM blocks, upsampling convolution modules, context feature enhancement blocks (CFEBs), and multiscale depthwise convolution blocks (MSDWCBs). The encoder consisting of TransNext-EMAM blocks is used for feature extraction and outputs the generated feature maps of each layer to CFEB through skip connections. In the feature reconstruction stage, CFEB can receive the jump-connected feature maps and the feature maps obtained from upsampling, which improves the network’s capacity to comprehend and localize the target objects and image details. MSDWCB can further enhance the multiscale feature extraction capability to achieve the effect of suppressing irrelevant regions to capture multiscale salient features. It effectively solves the challenge of combining local and global information in complex scenes. It also enhances the robustness of the network in extracting buildings in complex scenes. Our method has been extensively experimented on the WHU building dataset, the Massachusetts building dataset, and the Inria building dataset. The intersection over union metrics on these three datasets are 91.21%, 76.12%, and 81.42, improving 1.06%, 1.55%, and 2.60%, respectively, compared with other state-of-the-art methods.

Zhenyu Liang, Senliang Bao, Weimin Zhang et al.

Satellite sea surface salinity (SSS) observations play a critical role in the study of ocean circulation and climate regulation. However, mesoscale salinity dynamics (e.g., eddies, fronts) remain poorly resolved by current salinity satellites, such as soil moisture and ocean salinity (SMOS), due to their low effective resolution (>100 km). To address this, we proposed the SMOS SSS super-resolution reconstruction (S5R2) network. This deep learning framework achieved super-resolution (SR) reconstruction of the SMOS L3 SSS product from 1/4° to 1/12° by fusing multivariate satellite observations. Our approach integrated a land filtering mechanism into a hybrid transformer-CNN architecture, enhancing both global and local attention to ocean dynamics while suppressing interference from land-based information. Meanwhile, we improved the search efficiency of the optimal subset of input variables by guiding the search direction and step size using prior knowledge. The results demonstrated that S5R2 outperformed existing L3 and L4 satellite SSS products and mainstream SR algorithms. Compared to the input SMOS L3 SSS product, S5R2 achieved a 20% and 60% reduction in root mean square error in the Kuroshio Extension and Gulf Stream regions, respectively. In addition, it improved the effective resolution from 100 km to 20–30 km, enabling the dynamic tracking of mesoscale eddies. This advance provides a near-real-time solution for monitoring fine-scale ocean salinity processes, with practical implications for ocean dynamics research and the operational application of salinity satellite products.

S. Giardiello, M. Gerbino, L. Pagano et al.

We study the effects due to mismatches in passbands, polarization angles, and temperature and polarization calibrations in the context of the upcoming cosmic microwave background experiment Simons Observatory (SO). Using the SO multi-frequency likelihood, we estimate the bias and the degradation of constraining power in cosmological and astrophysical foreground parameters assuming different levels of knowledge of the instrumental effects. We find that incorrect but reasonable assumptions about the values of all the systematics examined here can have significant effects on cosmological analyses, hence requiring marginalization approaches at the likelihood level. When doing so, we find that the most relevant effect is due to bandpass shifts. When marginalizing over them, the posteriors of parameters describing astrophysical microwave foregrounds (such as radio point sources or dust) get degraded, while cosmological parameters constraints are not significantly affected. Marginalization over polarization angles with up to 0.25° uncertainty causes an irrelevant bias ≲ 0.05 σ in all parameters. Marginalization over calibration factors in polarization broadens the constraints on the effective number of relativistic degrees of freedom Neff by a factor 1.2, interpreted here as a proxy parameter for non standard model physics targeted by high-resolution CMB measurements.

P. Agnes, H. Back, W. Bonivento et al.

The existence of dark matter in the universe is inferred from abundant astrophysical and cosmological observations. The Global Argon Dark Matter Collaboration (GADMC) aims to perform the searches for dark matter in the form of weakly interacting massive particles (WIMPs), whose collisions with argon nuclei would produce nuclear recoils with tens of keV energy. Argon has been considered an excellent medium for the direct detection of WIMPs as argon-based scintillation detectors can make use of pulse shape discrimination (PSD) to separate WIMP-induced nuclear recoil signals from electron recoil backgrounds with extremely high efficiency. However, argon-based direct dark matter searches must confront the presence of intrinsic 39Ar as the predominant source of electron recoil backgrounds (it is a beta-emitter with an endpoint energy of 565 keV and half-life of 269 years). Even with PSD, the 39Ar activity in atmospheric argon (AAr), mainly produced and maintained by cosmic ray-induced nuclear reactions, limits the ultimate size of argon-based detectors and restricts their ability to probe very-low-energy events. The discovery of argon from deep underground wells with significantly less 39Ar than that in AAr was an important step in the development of direct dark matter detection experiments using argon as the active target. Thanks to pioneering research and successful R&D, in 2012, the first 160 kg batch of underground argon (UAr) was extracted from a CO2 well in Cortez, Colorado. The DarkSide-50 experiment at the Gran Sasso National Laboratory (LNGS) in Italy, the first liquid argon detector ever operated with a UAr target, demonstrated a ∼ 1,400 suppression of the 39Ar activity with respect to the atmospheric argon. An even larger suppression is expected for 42Ar (another intrinsic beta-emitter with the 42K daughter isotope, also a beta-emitter) as its production is expected mainly in the upper atmosphere. Following the results of DarkSide-50, the GADMC initiated the UAr project for extraction from underground and cryogenic purification of 100 t of argon to be used as a target in the next-generation experiment DarkSide-20k. This paper contains a description of the Urania Plant in Cortez, Colorado, where UAr is extracted; the Aria Plant in Sardinia, Italy, an industrial-scale plant comprising a 350-m state-of-the-art cryogenic isotopic distillation column, designed for further purification of the extracted argon and further reduction of the isotopic abundance of 39Ar; and DArT, a facility for UAr radiopurity qualification at the Canfranc Underground Laboratory (LSC), Spain. Moreover, the high radiopurity of UAr leads to other possible applications, for instance, for those neutrinoless double-beta decay experiments using argon as shielding material or, more generally, for all those activities on argon-based detectors in high-energy physics or nuclear physics, which will be briefly discussed.

G. Levy, J. A. Helayël-Neto

In this paper, we endeavour to build up a non-Abelian formulation to describe the self-interactions of massless vector bosons in the context of Loop Quantum Gravity (LQG). To accomplish this task, we start off from the modified Maxwell equations with the inclusion of LQG corrections and its corresponding local $U(1)$ gauge invariance. LQG effects in the electromagnetic interactions have significant importance, as they might be adopted to describe the flight time of cosmic photons coming from very high-energy explosions in the Universe, such as events of Gamma-Ray Bursts (GRBs). These photons have energy-dependent speeds, indicating that the velocity of light in the vacuum is not constant. To carry out the extension from the Abelian to the non-Abelian scenario, we shall follow the so-called Noether current procedure, which consists in recurrently introducing self-interactions into an initially free action for vector bosons by coupling the latter to the conserved currents of a global symmetry present in the action of departure. In the end of the non-Abelianization process, the initial global symmetry naturally becomes local. Once the Yang-Mills system includes LQG correction terms, it becomes possible to analyze how quantum-gravity induced contributions show up in both the electroweak and the QCD sectors of the Standard Model, providing a set-up for phenomenological investigations that may bring about new elements to discuss Physics beyond the Standard-Model.

F. Halzen, P. Lipari

We describe the pioneering contributions of Thomas K. Gaisser to the birth and development of particle astrophysics, a new field of research at the intersection of cosmic ray physics, astronomy, astrophysics, and particle physics that has emerged in the last few decades. We will especially focus on his studies of natural beams of neutrinos: those generated by the interactions of cosmic rays in the Earth's atmosphere and those emitted by astrophysical sources. Tom actively participated in the discovery of these cosmic neutrinos as well. His contributions also extend to gamma-ray astronomy, the study of the cosmic ray spectra and composition, and the modeling of cosmic ray interactions in the atmosphere and in astrophysical environments. Tom invariably focused his research on the theoretical and phenomenological problems of greatest interest at the time, producing frameworks that transparently interpreted often complex data. These studies have been very influential and have shaped the development of the field.

B. Sanjay

The complex dynamics of constructive resonance are the main topic of this quantum physics study, along with its implications for matter generation, the unification of quantum and classical knowledge, and important technological developments. Space-time is conceptualized in terms of an interwoven fabric in which both linear and non-linear patterns are recorded in an information field. According to this paradigm, basic particle interactions that result in the development of the material universe are referred to as "Constructive Resonance Waves." A five-dimensional cosmos is shaped by the introduction of Cosmic Information (CI), which is essential since it is a basic base vector related to the dimensions of space and time. The Resonance-Induced Information Force Field (RIIFF) and Constructive Resonance are two new theoretical concepts that are introduced in this paper.

Álvaro S. de Jesus, M. M. Paixão, Dêivid R. da Silva et al.

The tension between direct measurements of the Hubble constant and those stemming from Cosmic Microwave Background probes has triggered a multitude of studies. The connection between cosmology and particle physics has shown to be a valuable approach to addressing the Hubble tension. In particular, increasing the number of relativistic degrees of freedom in the early universe helps alleviate the problem. In this work, we write down effective field theory describing relativistic dark matter production in association with neutrinos leading to a larger $H_0$. We derive limits on the effective energy scale that governs this relativistic production of dark matter as a function of the dark matter mass for fermion, vector, and scalar dark matter fields. In particular, scalar dark matter particles are more effective in increasing the effective number of relativistic species. Also, if they have weak scale masses, then the relativistic production of dark matter should be governed by Planck scale effective operators in order to alleviate the Hubble tension.

Hongli An, Liying Hou, Manwai Yuen

The rotating shallow water system is an important physical model, which has been widely used in many scientific areas, such as fluids, hydrodynamics, geophysics, oceanic and atmospheric dynamics. In this paper, we extend the application of the Adomian decomposition method from the single equation to the coupled system to investigate the numerical solutions of the rotating shallow water system with an underlying circular paraboloidal basin. By introducing some special initial values, we obtain interesting approximate pulsrodon solutions corresponding to pulsating elliptic warm-core rings, which take the form of realistic series solutions. Numerical results reveal that the numerical pulsrodon solutions can quickly converge to the exact solutions derived by Rogers and An, which fully shows the efficiency and accuracy of the proposed method. Note that the method proposed can be effectively used to construct numerical solutions of many nonlinear mathematical physics equations. The results obtained provide some potential theoretical guidance for experts to study the related phenomena in geography, oceanic and atmospheric science.

Patrick Beaudry, Dimitri A. Sverjensky

Abstract Recycling of oxidized sulfur from subducting slabs to the mantle wedge provides simultaneous explanations for the elevated oxygen fugacity (fO2) in subduction zones, their high hydrothermal and magmatic sulfur outputs, and the enriched sulfur isotopic signatures (i.e., δ34S > 0‰) of these outputs. However, a quantitative understanding of the abundance and speciation of sulfur in slab fluids consistent with high pressure experiments is lacking. Here we analyze published experimental data for anhydrite solubility in H2O‐NaCl solutions to calibrate a high‐pressure aqueous speciation model of sulfur within the framework of the deep earth water model. We characterize aqueous complexes, required to account for the high experimental anhydrite solubilities. We then use this framework to predict the speciation and solubility of sulfur in chemically complex fluids in equilibrium with model subducting mafic and ultramafic lithologies, from 2 to 3 GPa and 400 to 800°C at log fO2 from FMQ‐2 to FMQ+4. We show that sulfate complexes of calcium and sodium markedly enhance the stability of sulfate in moderately oxidized fluids in equilibrium with pyrite at fO2 conditions of FMQ+1 to +2, causing large sulfur isotope fractionations up to 10‰ in the fluid relative to the slab. Such fluids could impart oxidized, sulfur‐rich and high δ34S signatures to the mantle wedge that are ultimately transferred to arc magmas, without the need to invoke 34S‐rich subducted lithologies.

Hongjian Ye, Weiming Chen, Diyong Wang et al.

Synthetic aperture radar (SAR), which can work normally under various meteorological conditions, has been widely researched and applied in marine vessel target monitoring and identification. Among the many research topics, due to the inconsistency of ship scale in SAR images, susceptibility to sea and land noise and clutter interference, resulting in a low detection rate of near-shore ship targets and inaccurate edge delineation of densely lined ships, a target detection algorithm based on deep convolutional neural network is proposed. The algorithm employs the channel-space grouping attention mechanism during feature extraction to enhance features by utilizing global positional and edge information associated with instances. The feature mobility fusion module is employed to merge features of various scales, bolster the interconnection among these features, and enhance multiscale ship target detection capabilities. The decoupled head is employed for ship target localization, while the angle-weighted intersection over union is used to mitigate regression errors. The experimental results show that the precision (P) achieved on HRSID and SSDD datasets reaches 94.81% and 99.01%, respectively, exceeding the control algorithm by more than 1.35% and 0.94%; the average precision (mAP) reaches 92.06% and 99.50%, respectively, exceeding the control algorithm by more than 2.32% and 2.51%; this indicates that the proposed algorithm has a good performance on SAR image ship detection and a strong generalization ability.

Ricardo Z. Ferreira, Silvia Gasparotto, Takashi Hiramatsu et al.

The evidence for a non-vanishing isotropic cosmic birefringence in recent analyses of the CMB data provides a tantalizing hint for new physics. Domain wall (DW) networks have recently been shown to generate an isotropic birefringence signal in the ballpark of the measured value when coupled to photons. In this work, we explore the axionic defects hypothesis in more detail and extending previous results to annihilating and late-forming networks, and by pointing out other smoking-gun signatures of the network in the CMB spectrum such as the anisotropic birefringent spectrum and B-modes. We also argue that the presence of cosmic strings in the network does not hinder a large isotropic birefringence signal because of an intrinsic environmental contribution coming from low redshifts thus leaving open the possibility that axionic defects can explain the signal. Regarding the remaining CMB signatures, with the help of dedicated 3D numerical simulations of DW networks, that we took as a proxy for the axionic defects, we show how the anisotropic birefringence spectrum combined with a tomographic approach can be used to infer the formation and annihilation time of the network. From the numerical simulations, we also computed the spectrum of gravitational waves (GWs) generated by the network in the post-recombination epoch and use previous searches for stochastic GW backgrounds in the CMB to derive for the first time a bound on the tension and abundance of networks with DWs that annihilate after recombination. Our bounds extend to the case where the network survives until the present time and improve over previous bounds by roughly one order of magnitude. Finally, we show the interesting prospects for detecting B-modes of DW origin with future CMB experiments.

P. Bhattacharjee, G. Sigl

Abstract Cosmic-ray particles with energies in excess of 10 20  eV have been detected. The sources as well as the physical mechanism(s) responsible for endowing cosmic-ray particles with such enormous energies are unknown. This report gives a review of the physics and astrophysics associated with the questions of origin and propagation of these extremely high-energy (EHE) cosmic-rays in the Universe. After a brief review of the observed cosmic rays in general and their possible sources and acceleration mechanisms, a detailed discussion is given of possible “top-down” ( non-acceleration ) scenarios of origin of EHE cosmic rays through decay of sufficiently massive particles originating from processes in the early Universe. The massive particles can come from collapse and/or annihilation of cosmic topological defects (such as monopoles, cosmic strings, etc.) associated with Grand Unified Theories or they could be some long-lived metastable supermassive relic particles that were created in the early Universe and are decaying in the current epoch. The highest energy end of the cosmic-ray spectrum can thus be used as a probe of new fundamental physics beyond Standard Model. We discuss the role of existing and proposed cosmic-ray, gamma-ray and neutrino experiments in this context. We also discuss how observations with next generation experiments of images and spectra of EHE cosmic-ray sources can be used to obtain new information on Galactic and extragalactic magnetic fields and possibly their origin.

J. Plane, J. Gumbel, K. Kalogerakis et al.

Abstract. This article begins with a review of important advances in the chemistry and related physics of the mesosphere and lower thermosphere (MLT) region of the atmosphere that have occurred over the past 2 decades, since the founding of Atmospheric Chemistry and Physics. The emphasis here is on chemistry, but we also discuss recent findings on atmospheric dynamics and forcings to the extent that these are important for understanding MLT composition and chemistry. Topics that are covered include observations, with satellite, rocket and ground-based techniques; the variability and connectedness of the MLT on various length scales and timescales; airglow emissions; the cosmic dust input and meteoric metal layers; and noctilucent/polar mesospheric ice clouds. The paper then concludes with a discussion of important unanswered questions and likely future directions for the field over the next decade.