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The Dark Side of the Screen—A Resistance to Changing Times
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作者 Maria Antónia Lima 《Journal of Literature and Art Studies》 2020年第9期829-834,共6页
This essay argues that black and white cinema spawned a resistance to changing times that is still very present in the new generation of directors who follow classic film traditions while subverting them with consiste... This essay argues that black and white cinema spawned a resistance to changing times that is still very present in the new generation of directors who follow classic film traditions while subverting them with consistent narrative inventions.The Artist,the best picture Oscar award winner in 2012,is an example of this resistance as it pays homage to some of the greatest silent films of the first two or three decades of cinema history.“The Dark Side of the Screen”aims to underline that there is an unchanging power of the phantasmagoria so present in black and white movies,produced not only in the silent era but also in film noir through lighting effects and camera angles which characterize the work of major noir directors like Fritz Lang,Billy Wilder,and Orson Welles,who knew everything about the unutterable mysteries hidden on the dark side of the screen. 展开更多
关键词 film noir black and white cinema dark side RESISTANCE
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Probing the dark side of the Universe with weak gravitational lensing effects
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作者 Li-Ping Fu Zu-Hui Fan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第9期1061-1120,共60页
Arising from gravitational deflections of light rays by large-scale struc- tures in the Universe, weak-lensing effects have been recognized as one of the most important probes in cosmological studies. In this paper, w... Arising from gravitational deflections of light rays by large-scale struc- tures in the Universe, weak-lensing effects have been recognized as one of the most important probes in cosmological studies. In this paper, we review the main progress in weak-lensing analyses, and discuss the challenges in future investigations aiming to understand the dark side of the Universe with unprecedented precisions. 展开更多
关键词 cosmology: dark matter and dark energy -- large-scale structure of uni- verse -- gravitational lensing
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Is it really the "dark side" of herbal medicine? 被引量:1
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作者 Yang Luan Shuangcheng Ma Yimin Mao 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第9期1118-1119,共2页
Aristolochic acids (AAs), previously rarely mentioned compounds, have been brought into the public eye several times since the beginning of this century; and currently, they have drawn even greater attention due to ... Aristolochic acids (AAs), previously rarely mentioned compounds, have been brought into the public eye several times since the beginning of this century; and currently, they have drawn even greater attention due to their association with liver cancer, as was recently reported by Ng et al.(Ng et al., 2017). The authors sequenced the whole exomes of 98patients with hepatocellular carcinomas (HCC) from Taiwan and reported that 78%of the cases carried the AAs mutational signature, A:T〉T:A transversion. 展开更多
关键词 HCC of herbal medicine Is it really the dark side
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DARK SIDE OF THE NET
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作者 DING WENLEI 《Beijing Review》 2007年第37期22-23,共2页
Internet viruses and hacking are growing problems in China that institutions and the government are struggling to
关键词 NET In dark side OF THE NET
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The Dark Side of the Moon
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《Beijing Review》 2007年第51期5-5,共1页
A combo photo released by the China National Space Administration(CNSA)on December 11 shows a crater on the dark side of the moon.This image was reportedly taken by Chang’e-1, the country’s first lunar probe,on Dece... A combo photo released by the China National Space Administration(CNSA)on December 11 shows a crater on the dark side of the moon.This image was reportedly taken by Chang’e-1, the country’s first lunar probe,on December 4. On December 12,a grand ceremony was held in Beijing to celebrate the success of the first stage of China’s lunar probe program.President Hu Jintao announced on the occasion that 展开更多
关键词 The dark side of the Moon
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Findings Dampen Hope of Water on Dark Side of Moon
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作者 章小景 《当代外语研究》 2004年第1期3-4,共2页
上个世纪90年代,科学家曾经猜测,在月球的背面可能存在着大量的冰态的水,这个猜想曾经一度点燃了人们的登月狂想,英语甚至造出了human col-onies on the Moon这样的表达!现在,进一步的探索dampened(本义:使潮湿;使沮丧)hopes of finding... 上个世纪90年代,科学家曾经猜测,在月球的背面可能存在着大量的冰态的水,这个猜想曾经一度点燃了人们的登月狂想,英语甚至造出了human col-onies on the Moon这样的表达!现在,进一步的探索dampened(本义:使潮湿;使沮丧)hopes of finding Large amounts of water on the dark side of the Moon。此句中的动词就足以让我们玩味一番。 展开更多
关键词 Findings Dampen Hope of Water on dark side of Moon
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Dynamical Dark Energy in Light of Cosmic Distance Measurements.Ⅱ.A Study Using Current Observations 被引量:1
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作者 Xiaoma Wang Gan Gu +2 位作者 Xiaoyong Mu Shuo Yuan Gong-Bo Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期15-20,共6页
We extract key information on dark energy from current observations of BAO,OHD and H_(0),and find hints of dynamical behavior of dark energy.In particular,a dynamical dark energy model whose equation of state crosses-... We extract key information on dark energy from current observations of BAO,OHD and H_(0),and find hints of dynamical behavior of dark energy.In particular,a dynamical dark energy model whose equation of state crosses-1 is favored by observations.We also find that the Universe has started accelerating at a lower redshift than expected. 展开更多
关键词 COSMOLOGY (cosmology:)dark energy cosmology:observations
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Comparison of displacement damage effects on the dark signal in CMOS image sensors induced by CSNS back-n and XAPR neutrons 被引量:1
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作者 Yuan-Yuan Xue Zu-Jun Wang +3 位作者 Wu-Ying Ma Min-Bo Liu Bao-Ping He Shi-Long Gou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期29-40,共12页
This study investigates the effects of displacement damage on the dark signal of a pinned photodiode CMOS image sensor(CIS)following irradiation with back-streaming white neutrons from white neutron sources at the Chi... This study investigates the effects of displacement damage on the dark signal of a pinned photodiode CMOS image sensor(CIS)following irradiation with back-streaming white neutrons from white neutron sources at the China spallation neutron source(CSNS)and Xi'an pulsed reactor(XAPR).The mean dark signal,dark signal non-uniformity(DSNU),dark signal distribution,and hot pixels of the CIS were compared between the CSNS back-n and XAPR neutron irradiations.The nonionizing energy loss and energy distribution of primary knock-on atoms in silicon,induced by neutrons,were calculated using the open-source package Geant4.An analysis combining experimental and simulation results showed a noticeable proportionality between the increase in the mean dark signal and the displacement damage dose(DDD).Additionally,neutron energies influence DSNU,dark signal distribution,and hot pixels.High neutron energies at the same DDD level may lead to pronounced dark signal non-uniformity and elevated hot pixel values. 展开更多
关键词 Displacement damage effects CMOS image sensor(CIS) CSNS back-n XAPR neutrons Geant4 dark signal non-uniformity(DSNU)
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Dark Matter Search in Dwarf Irregular Galaxies with Ten Years of Data from the Ice Cube Neutrino Observatory
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作者 Yi-Fei Lü Ben-Yang Zhu +4 位作者 Rong-Lan Li Xue-Kang Guo Tian-Ci Liu Yong-Bo Huang Yun-Feng Liang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期75-82,共8页
Dwarf irregular galaxies(dIrrs),as rotationally supported systems,have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent year... Dwarf irregular galaxies(dIrrs),as rotationally supported systems,have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent years.In this paper,we use 10 yr of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of seven dIrrs,aiming to detect neutrinos produced by heavy annihilation dark matter.We do not detect any significant signal.Based on such null results,we calculate the upper limits on the velocity-averaged annihilation cross section for 1 TeV–10 PeV dark matter.Our limits,although weaker than the strictest constraints in the literature in this mass range,are also a good complement to the existing results considering the more reliable J-factor measurements of dIrrs. 展开更多
关键词 (cosmology) dark matter-cosmology theory-galaxies DWARF
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Applying the Dark Target Aerosol Algorithm to MERSI-Ⅱ:Retrieval and Validation of Aerosol Optical Depth over the Ocean
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作者 Xin PEI Leiku YANG +4 位作者 Weiqian JI Shuang CHEN Xiaoqian CHENG Xiaofeng LU Hongtao WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第12期2446-2463,共18页
The Medium-Resolution Spectral Imager-Ⅱ(MERSI-Ⅱ)instrument aboard China’s Fengyun-3D satellite shares similarities with NASA’s Moderate Resolution Imaging Spectroradiometer(MODIS)sensor,enabling the retrieval of g... The Medium-Resolution Spectral Imager-Ⅱ(MERSI-Ⅱ)instrument aboard China’s Fengyun-3D satellite shares similarities with NASA’s Moderate Resolution Imaging Spectroradiometer(MODIS)sensor,enabling the retrieval of global aerosol optical depth(AOD).However,no officially released operational MERSI-Ⅱ aerosol products currently exist over the ocean.This study focuses on adapting the MODIS dark target(DT)ocean algorithm to the MERSI-Ⅱ sensor.A retrieval test is conducted on the 2019 MERSI-Ⅱ data over the global ocean,and the retrieved AODs are validated against ground-based measurements from the automatic Aerosol Robotic Network(AERONET)and the shipborne Maritime Aerosol Network(MAN).The operational MODIS DT aerosol products are also used for comparison purposes.The results show that MERSI-Ⅱ AOD granule retrievals are in good agreement with MODIS products,boasting high correlation coefficients(R)of up to 0.96 and consistent spatial distribution trends.Furthermore,the MERSI-Ⅱ retrievals perform well in comparison to AERONET and MAN measurements,with high R-values(>0.86).However,the low-value retrievals from MERSI-Ⅱ tend to be slightly overestimated compared to MODIS,despite both AODs displaying a positive bias.Notably,the monthly gridded AODs over the high latitudes of the northern and southern hemispheres suggest that MERSI-Ⅱ exhibits greater stability in space and time,effectively reducing unrealistically high-value noise in the MODIS products.These results illustrate that the MERSI-Ⅱ retrievals meet specific accuracy requirements by maintaining the algorithmic framework and most of the algorithmic assumptions,providing a crucial data supplement for aerosol studies and climate change. 展开更多
关键词 aerosol optical depth MERSI-Ⅱ MODIS dark target
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Design of hadronic calorimeter for DarkSHINE experiment
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作者 Zhen Wang Rui Yuan +18 位作者 Han-Qing Liu Jing Chen Xiang Chen Kim Siang Khaw Liang Li Shu Li Kun Liu Qi-Bin Liu Si-Yuan Song Tong Sun Xiao-Long Wang Yu-Feng Wang Hai-Jun Yang Jun-Hua Zhang Yu-Lei Zhang Zhi-Yu Zhao Chun-Xiang Zhu Xu-Liang Zhu Yi-Fan Zhu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期155-167,共13页
The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used ... The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector geometry.This paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation framework.The geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV level.The overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives. 展开更多
关键词 Hadronic calorimeter GEANT4 simulation Neutron background Scintillation detector dark photon
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Inelastic Scattering of Dark Matter with Heavy Cosmic Rays
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作者 Keyu Lu Yue-Lin Sming Tsai +1 位作者 Qiang Yuan Le Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期68-80,共13页
We investigate the impact of inelastic collisions between dark matter(DM)and heavy cosmic ray(CR)nuclei on CR propagation.We approximate the fragmentation cross-sections for DM-CR collisions using collider-measured pr... We investigate the impact of inelastic collisions between dark matter(DM)and heavy cosmic ray(CR)nuclei on CR propagation.We approximate the fragmentation cross-sections for DM-CR collisions using collider-measured proton-nuclei scattering cross-sections,allowing us to assess how these collisions affect the spectra of CR boron and carbon.We derive new CR spectra from DM-CR collisions by incorporating their cross-sections into the source terms and solving the diffusion equation for the complete network of reactions involved in generating secondary species.In a specific example with a coupling strength of b_(χ)=0.1 and a DM mass of m_(χ)=0.1 GeV,considering a simplified scenario where DM interacts exclusively with oxygen,a notable modification in the boron-to-carbon spectrum due to the DM-CR interaction is observed.Particularly,the peak within the spectrum,spanning from 0.1 to 10 GeV,experiences an enhancement of approximately 1.5 times.However,in a more realistic scenario where DM particles interact with all CRs,this peak can be amplified to twice its original value.Utilizing the latest data from AMS-02 and DAMPE on the boron-to-carbon ratio,we estimate a 95%upper limit for the effective inelastic cross-section of DM-proton as a function of DM mass.Our findings reveal that at m_(χ)?2 MeV,the effective inelastic cross-section between DM and protons must be less than O(10^(-32))cm^(2). 展开更多
关键词 elementary particles nuclear reactions NUCLEOSYNTHESIS ABUNDANCES SCATTERING astroparticle physics (cosmology:)dark matter
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Organic X-Ray Image Sensors Using a Medium Bandgap Polymer Donor with Low Dark Current
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作者 Jong-Woon Ha Seung Hun Eom +11 位作者 Bo Kyung Cha Seyeong Song Hyeong Ju Eun Jong H.Kim Jong Mok Park BongSoo Kim Byoungwook Park Seo-Jin Ko Sung Cheol Yoon Changjin Lee In Hwan Jung Do-Hoon Hwang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期230-237,共8页
The development of portable X-ray detectors is necessary for diagnosing fractures in unconscious patients in emergency situations.However,this is quite challenging because of the heavy weight of the scintillator and s... The development of portable X-ray detectors is necessary for diagnosing fractures in unconscious patients in emergency situations.However,this is quite challenging because of the heavy weight of the scintillator and silicon photodetectors.The weight and thickness of X-ray detectors can be reduced by replacing the silicon layer with an organic photodetectors.This study presents a novel bithienopyrroledione-based polymer donor that exhibits excellent photodetection properties even in a thick photoactive layer(~700 nm),owing to the symmetric backbone and highly soluble molecular structure of bithienopyrroledione.The ability of bithienopyrroledione-based polymer donor to strongly suppress the dark current density(Jd~10−10 A cm^(−2))at a negative bias(−2.0 V)while maintaining high responsivity(R=0.29 A W−1)even at a thickness of 700 nm results in a maximum shot-noise-limited specific detectivity of D_(sh)^(*)=2.18×10^(13)Jones in the organic photodetectors.Printed organic photodetectors are developed by slot-die coating for use in X-ray detectors,which exhibit D_(sh)^(*)=2.73×10^(12)Jones with clear rising(0.26 s)and falling(0.29 s)response times upon X-ray irradiation.Detection reliability is also proven by linear response of the X-ray detector,and the X-ray detection limit is 3 mA. 展开更多
关键词 low dark current low detection limit organic photodetector printable X-RAY
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A large language model-powered literature review for high-angle annular dark field imaging
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作者 Wenhao Yuan Cheng Peng Qian He 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期76-81,共6页
High-angle annular dark field(HAADF)imaging in scanning transmission electron microscopy(STEM)has become an indispensable tool in materials science due to its ability to offer sub-°A resolution and provide chemic... High-angle annular dark field(HAADF)imaging in scanning transmission electron microscopy(STEM)has become an indispensable tool in materials science due to its ability to offer sub-°A resolution and provide chemical information through Z-contrast.This study leverages large language models(LLMs)to conduct a comprehensive bibliometric analysis of a large amount of HAADF-related literature(more than 41000 papers).By using LLMs,specifically ChatGPT,we were able to extract detailed information on applications,sample preparation methods,instruments used,and study conclusions.The findings highlight the capability of LLMs to provide a new perspective into HAADF imaging,underscoring its increasingly important role in materials science.Moreover,the rich information extracted from these publications can be harnessed to develop AI models that enhance the automation and intelligence of electron microscopes. 展开更多
关键词 large language models high-angle annular dark field imaging deep learning
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Highly Defective Dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties
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作者 E.D.Fakhrutdinova O.A.Reutova +6 位作者 T.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus D.B.Vasilchenko O.V.Vodyankina V.A.Svetlychnyi 《Transactions of Tianjin University》 EI CAS 2024年第2期198-209,共12页
The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibite... The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation. 展开更多
关键词 dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type PHOTOCATALYSIS Hydrogen evolution reaction
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Implications of the Stellar Mass Density of High-z Massive Galaxies from JWST on Warm Dark Matter
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作者 Hengjie Lin Yan Gong +1 位作者 Bin Yue Xuelei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期128-134,共7页
A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation efficiency.However,this wi... A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation efficiency.However,this will lead to large number density of ionizing photons in the epoch of reionization(EoR),so that the reionization history will be changed,which can arise tension with the current EoR observations.Warm dark matter(WDM),via the free streaming effect,can suppress the formation of small-scale structure as well as low-mass galaxies.This provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-z massive galaxies without altering the cosmic reionization history.On the other hand,the constraints on the properties of WDM can be derived from the JWST observations.In this work,we study WDM as a possible solution to reconcile the JWST stellar mass density of high-z massive galaxies and reionization history.We find that,the JWST high-z comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM model.But using the observational data of other stellar mass density measurements and reionization history,we obtain that the WDM particle mass with mw=0.51_(-0.12)^(+0.22) keV and star formation efficiency parameter f_(*)^(0)> 0.39 in 2σ confidence level can match both the JWST high-z comoving cumulative stellar mass density and the reionization history. 展开更多
关键词 COSMOLOGY (cosmology:)dark matter (cosmology:)large-scale structure of universe
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Dynamical Dark Energy in Light of Cosmic Distance Measurements.Ⅰ.A Demonstration Using Simulated Datasets
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作者 Gan Gu Xiaoma Wang +2 位作者 Xiaoyong Mu Shuo Yuan Gong-Bo Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期7-14,共8页
We develop methods to extract key dark energy information from cosmic distance measurements including the BAO scales and supernova(SN) luminosity distances.Demonstrated using simulated data sets of the complete DESI,L... We develop methods to extract key dark energy information from cosmic distance measurements including the BAO scales and supernova(SN) luminosity distances.Demonstrated using simulated data sets of the complete DESI,LSST and Roman surveys designed for BAO and SN distance measurements,we show that using our method,the dynamical behavior of the energy,pressure,equation of state(with its time derivative) of dark energy and the cosmic deceleration function can all be accurately recovered from high-quality data,which allows for robust diagnostic tests for dark energy models. 展开更多
关键词 (cosmology:)dark energy (cosmology:)large scale structure of universe (cosmology:)cosmic background radiation (cosmology:)cosmological parameters
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Dark Galaxies, Sun-Earth-Moon Interaction, Tunguska Event—Explained by WUM
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期836-853,共18页
Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fa... Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fact, an object the size of a galaxy, made entirely of dark matter. They found that the speed of the Earth’s rotation varies randomly each day. 115 years ago, the Tunguska Event was observed, and astronomers still do not have an explanation of It. Main results of the present article are: 1) Dark galaxies explained by the spinning of their Dark Matter Cores with the surface speed at equator less than the escape velocity. Their Rotational Fission is not happening. Extrasolar systems do not emerge;2) 21-cm Emission explained by the self-annihilation of Dark Matter particles XIONs (5.3 μeV);3) Sun-Earth-Moon Interaction explained by the influence of the Sun’s and the Moon’s magnetic field on the electrical currents of the charged Geomagma (the 660-km layer), and, as a result, the Earth’s daylength varies;4) Tunguska Event explained by a huge atmospheric explosion of the Superbolide, which was a stable Dark Matter Bubble before entering the Earth’s atmosphere. 展开更多
关键词 World-Universe Model dark Stars dark Galaxies 21-cm Emission Formation of Macrostructures Sun-Earth-Moon Interaction Tunguska Event dark Matter
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A Dark Matter Theory by Quantum Gravitation for Galaxies and Clusters
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作者 Manuel Abarca 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1749-1784,共36页
This paper develops an original theory of dark matter in the current ΛCDM framework, whose main hypothesis is that DM is generated by the own gravitational field, according to an unknown quantum gravitational phenome... This paper develops an original theory of dark matter in the current ΛCDM framework, whose main hypothesis is that DM is generated by the own gravitational field, according to an unknown quantum gravitational phenomenon. This work is the best version of the theory, which I have been developing and publishing since 2014. The hypothesis of DM by quantum gravitation, DMbQG hereafter, has two main consequences: the first one is that the law of DM generation has to be the same, in the halo region, for all the galaxies and the second one is that the haloes are unbounded, so the total DM goes up without limit as the gravitational field is unbounded as well. The first one consequence is backed by the fact that M31 and MW has a fitted function with the same power exponent for the rotation curve at the halo region and both giant galaxies are the only ones whose rotation curves at the halo region may be studied with accuracy. This paper is firstly developed all the theory with M31 rotation curve data up to Chapter 9. The most important formula of the theory is the called Direct mass, which calculates the total mass at a specific radius into the halo region. Chapter 10 is dedicated to apply the theory to Milky Way, it is calculated its total mass at different radius into the halo and such results have been validated successfully using the data of masses at different radius published by two researcher teams. In Chapter 11, it is calculated the direct mass for the Local Group, and it is shown how the DMbQG theory is able to calculate the total mass at 770 kpc, that the dynamical methods estimate to be 5×1012MΘ. In Chapter 12, it is shown a method to estimate the Direct mass formula for a cluster of galaxies, using only its virial mass and virial radius. By this method, it is estimated the parameter a2 of the Local Group, which match with the one calculated in previous chapter by a different method. Also are calculated the parameters a2 associated to Virgo and Coma clusters. In Chapter 13, it is demonstrated how the DE is able to counterbalance the DM at cluster scale, as the Direct mass grows up with the square root of radius whereas the DE grows up with the cubic power. The chapter is an introduction to the DMbQG theory for cluster of galaxies, which has been developed fully by the author in other works. This theory aims to be a powerful method to study DM in the halo region of galaxies and cluster of galaxies and conversely the measures in galaxies and clusters offer the possibility to validate the theory. 展开更多
关键词 dark Matter dark Energy GALAXIES Local Group of Galaxies CLUSTERS
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A Dark Energy Hypothesis I
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作者 James Togeas 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1138-1141,共4页
The cosmological constant, Λ, represents dark energy. The dark energy hypothesis (DEH) replaces Λ with a variable quantity, the cosmological parameter: Λ=1a2η2In this formula, “a” is the scale factor and η the ... The cosmological constant, Λ, represents dark energy. The dark energy hypothesis (DEH) replaces Λ with a variable quantity, the cosmological parameter: Λ=1a2η2In this formula, “a” is the scale factor and η the conformal time: adη = cdt. A companion paper (DEH II) develops and explores a cosmological model with this variable parameter. This paper portrays the origin of the cosmological parameter in the uncoupling of time and space in the early universe from a prior state in which the comoving coordinates x0 = η and x1 = χ, the cosmic latitude, are coupled. In this hypothesis dark matter is a co-product of the decoupling, but its nature remains mysterious. 展开更多
关键词 dark Energy dark Matter Cosmological Constant Tensor Calculus
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