Log in

Relevant bibliographies by topics / Universe through observations / Journal articles

To see the other types of publications on this topic, follow the link: Universe through observations.

Journal articles on the topic 'Universe through observations'

Author: Grafiati

Published: 2 June 2025

Last updated: 31 July 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Universe through observations.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Yu, Ziguan. "The Flatness of The Universe Through Theory and Observations." Highlights in Science, Engineering and Technology 112 (August 20, 2024): 314–18. http://dx.doi.org/10.54097/b816cb51.

Full text

Abstract:

Understanding the universe's shape is crucial for cosmology. Whether the shape is flat not only influences many other studies based on the assumption that the universe is flat but also helps people to build a better model to explain the evolution of the universe. This paper introduces several available methods to determine its flatness, focusing on the basic ideas and related theories. The paper mainly introduces the method of using the CMB's angular power spectrum to determine the universe's shape and gives the conclusion of a flat universe. Utilizing the lambda-CDM model, which suggests a ne

APA, Harvard, Vancouver, ISO, and other styles

2

Bahcall, Neta A. "Dark matter universe." Proceedings of the National Academy of Sciences 112, no. 40 (2015): 12243–45. http://dx.doi.org/10.1073/pnas.1516944112.

Full text

Abstract:

Most of the mass in the universe is in the form of dark matter—a new type of nonbaryonic particle not yet detected in the laboratory or in other detection experiments. The evidence for the existence of dark matter through its gravitational impact is clear in astronomical observations—from the early observations of the large motions of galaxies in clusters and the motions of stars and gas in galaxies, to observations of the large-scale structure in the universe, gravitational lensing, and the cosmic microwave background. The extensive data consistently show the dominance of dark matter and quan

APA, Harvard, Vancouver, ISO, and other styles

3

Thompson, Rodger I. "Observational Determinations of the Proton to Electron Mass Ratio in the Early Universe." Proceedings of the International Astronomical Union 5, H15 (2009): 319. http://dx.doi.org/10.1017/s1743921310009567.

Full text

Abstract:

AbstractThe values of the fundamental physical constants determine the nature of our universe from the height of mountains on earth to the evolution of the universe over its history. One of these constants is μ = MP/Me the ratio of the proton to electron mass. Astronomical observations provide a determination of this ratio in the early universe through observations of molecular absorption and emission lines in distant objects. Observations of molecular hydrogen in distant damped Lyman Alpha clouds provide a measurement of μ at a time when the universe was only 20% of its present age. To date t

APA, Harvard, Vancouver, ISO, and other styles

4

Shao, Xiaoyun, Zhoujian Cao, Xilong Fan, and Shichao Wu. "Probing the Large-scale Structure of the Universe Through Gravitational Wave Observations." Research in Astronomy and Astrophysics 22, no. 1 (2022): 015006. http://dx.doi.org/10.1088/1674-4527/ac32b4.

Full text

Abstract:

Abstract The improvements in the sensitivity of the gravitational wave (GW) network enable the detection of several large redshift GW sources by third-generation GW detectors. These advancements provide an independent method to probe the large-scale structure of the universe by using the clustering of the binary black holes (BBHs). The black hole catalogs are complementary to the galaxy catalogs because of large redshifts of GW events, which may imply that BBHs are a better choice than galaxies to probe the large-scale structure of the universe and cosmic evolution over a large redshift range.

APA, Harvard, Vancouver, ISO, and other styles

5

Schmidt, Brian P. "Nobel Lecture: Accelerating expansion of the Universe through observations of distant supernovae." Reviews of Modern Physics 84, no. 3 (2012): 1151–63. http://dx.doi.org/10.1103/revmodphys.84.1151.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Kafatos, Menas. "Knowledge Limits in Cosmology." Symposium - International Astronomical Union 168 (1996): 431–38. http://dx.doi.org/10.1017/s0074180900110307.

Full text

Abstract:

In cosmology one faces the observational challenge that knowledge about distant regions of the universe is dependent on assumptions one makes about these regions which are themselves coupled to the observations. Within the framework of the Friedmann-Robertson-Walker big bang models the universe becomes opaque to its own radiation at z ≈ 1,000 and the earlier, and more distant, regions of the universe are not directly accessible through observations. Other challenges exist such as possible merging of extended distant sources and confusion of spectra from distant galaxies. One, therefore, encoun

APA, Harvard, Vancouver, ISO, and other styles

7

Baghram, Shant, Saeed Tavasoli, Farhang Habibi, Roya Mohayaee, and Joseph Silk. "Unraveling the nature of gravity through our clumpy universe." International Journal of Modern Physics D 23, no. 12 (2014): 1442025. http://dx.doi.org/10.1142/s0218271814420255.

Full text

Abstract:

We propose a new probe to test the nature of gravity at various redshifts through large-scale cosmological observations. We use our void catalog, extracted from the Sloan Digital Sky Survey (SDSS, DR10), to trace the distribution of matter along the lines of sight to SNe Ia that are selected from the Union II catalog. We study the relation between SNe Ia luminosities and convergence and also the peculiar velocities of the sources. We show that the effects, on SNe Ia luminosities, of convergence and of peculiar velocities predicted by the theory of general relativity and theories of modified gr

APA, Harvard, Vancouver, ISO, and other styles

8

Pandey, A. "STELLAR EVOLUTION AND THEIR ASTRONOMICAL OBSERVATIONS." Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias 53 (September 1, 2021): 147–50. http://dx.doi.org/10.22201/ia.14052059p.2021.53.29.

Full text

Abstract:

There is a hugh number of stars (~ few hundred billions) of different ages, sizes and masses in our galaxy, the Milky Way, and billions of other galaxies in the Universe. It was extremely challenging for astronomers to classify them into different groups to understand their properties precisely. In general, stars remains in the main sequence phases in the HR diagram for the largest fraction of its life time because it maintains hydro-static equilibrium during this phase. Stars of diverse mass range pass through different evolutionary phases. Some of these end their lives as catastrophic explos

APA, Harvard, Vancouver, ISO, and other styles

9

Trinchieri, Ginevra. "XMM-Newton observations of elliptical galaxies in the local universe." Proceedings of the International Astronomical Union 5, H15 (2009): 273. http://dx.doi.org/10.1017/s1743921310009178.

Full text

Abstract:

XMM-Newton is well suited to the study of the X-ray properties of early-type galaxies: the wide energy band allows a characterization of the different components of the X-ray emission in galaxies, separating the gas from the compact source component through their spectral characteristics, and identifying low-luminosity absorbed AGNs; the large field of view allows a proper understanding of the large scale emission, and the separation between the galaxy and the surrounding group. Nonetheless, in spite of the much improved understanding of the X-ray characteristics of this class of sources, much

APA, Harvard, Vancouver, ISO, and other styles

10

Kinney, Sean. "Calculating All Dark Energy and Dark Matter Effects through Dynamic Gravity Theory." European Journal of Physical Sciences 6, no. 2 (2023): 1–10. http://dx.doi.org/10.47672/ejps.1503.

Full text

Abstract:

Newton’s Universal Law of Gravitation was augmented by Einstein’s General Relativity to include factors such as time dilation from speed and gravity field strength. But this augmentation has proven to be incomplete as the math fails in almost all settings outside our solar system hence the need for Dark Energy and Dark Matter to resolve the math. Dynamic Gravity has new math that augments GR in much the same way GR augments Newton’s Law, and this math has the potential to completely explain the motions of all celestial bodies throughout the entire universe with zero need to correct the math wi

APA, Harvard, Vancouver, ISO, and other styles

11

Ahmed, Nasr, and Sultan Z. Alamri. "A stable flat entropy-corrected FRW universe." International Journal of Geometric Methods in Modern Physics 16, no. 10 (2019): 1950159. http://dx.doi.org/10.1142/s0219887819501597.

Full text

Abstract:

In this paper, a general entropy-corrected FRW cosmological model has been presented in which a deceleration-to-acceleration transition occurs according to recent observations. We found that the case for the flat universe ([Formula: see text]), supported by observations, is the most stable one where it successfully passes all stability tests. The stability of the model has been studied through testing the sound speed, the classical and the new nonlinear energy conditions. The model predicts a positive pressure during the early-time decelerating epoch, and a negative pressure during the late-ti

APA, Harvard, Vancouver, ISO, and other styles

12

Li, Tjonnie G. F. "Gravitational-wave observations from ground-based detectors." International Journal of Modern Physics A 32, no. 28n29 (2017): 1744002. http://dx.doi.org/10.1142/s0217751x1744002x.

Full text

Abstract:

Recent detections of gravitational waves by the LIGO detectors herald a new era of observational astronomy. Previously invisible objects and phenomena may now be uncovered through their gravitational interaction. Observation of gravitational waves allows one to explore the extremes of the Universe and study astronomy and fundamental physics like never before. This article gives a brief overview of the detection process, from the production of the data to their physical implications.

APA, Harvard, Vancouver, ISO, and other styles

13

Lin, Jiuru. "Application of gravitational wave detection technology in astronomical observations." Theoretical and Natural Science 9, no. 1 (2023): 280–84. http://dx.doi.org/10.54254/2753-8818/9/20240783.

Full text

Abstract:

Gravitational waves are waves that propagate through space and time due to the interaction of gravity, representing a completely new physical phenomenon. This article reviews the background and issues of gravitational wave detection, with a focus on the progress of interdisciplinary research. It was not until 2015 that researchers successfully detected gravitational waves for the first time, capturing gravitational wave signals from the merger of two black holes using laser interferometry technology. This breakthrough confirms the predictions of Einstein's general relativity and opens a new ch

APA, Harvard, Vancouver, ISO, and other styles

14

DUNSBY, PETER K. S., and MARCO BRUNI. "CONSERVED QUANTITIES IN PERTURBED INFLATIONARY UNIVERSES." International Journal of Modern Physics D 03, no. 02 (1994): 443–59. http://dx.doi.org/10.1142/s0218271894000629.

Full text

Abstract:

Given that observations seem to favour a density parameter Ω0<1, corresponding to an open universe, we consider gauge-invariant perturbations of nonflat Robertson-Walker universes filled with a general imperfect fluid which can also be taken to represent a scalar field. Our aim is to set up the equations that govern the evolution of the density perturbations Δ so that it can be determined through a first order differential equation with a quantity [Formula: see text] which is conserved at any length scale, even in nonflat universe models, acting as a source term. The quantity [Formula: see

APA, Harvard, Vancouver, ISO, and other styles

15

Kahniashvili, Tina, Axel Brandenburg, Arthur Kosowsky, Sayan Mandal, and Alberto Roper Pol. "Magnetism in the Early Universe." Proceedings of the International Astronomical Union 14, A30 (2018): 295–98. http://dx.doi.org/10.1017/s1743921319004447.

Full text

Abstract:

AbstractBlazar observations point toward the possible presence of magnetic fields over intergalactic scales of the order of up to ∼1 Mpc, with strengths of at least ∼10−16 G. Understanding the origin of these large-scale magnetic fields is a challenge for modern astrophysics. Here we discuss the cosmological scenario, focussing on the following questions: (i) How and when was this magnetic field generated? (ii) How does it evolve during the expansion of the universe? (iii) Are the amplitude and statistical properties of this field such that they can explain the strengths and correlation length

APA, Harvard, Vancouver, ISO, and other styles

16

Krennrich, Frank. "TeV GAMMA RAYS: OBSERVATIONS VERSUS EXPECTATIONS & THEORY." Acta Polytechnica 53, A (2013): 635–40. http://dx.doi.org/10.14311/ap.2013.53.0635.

Full text

Abstract:

The scope of this paper is to discuss two important questions relevant for TeV γ-ray astronomy; the pursuit to reveal the origin of cosmic rays in our galaxy, and the opacity of the universe in γ-rays. The origin of cosmic rays stipulated the field of TeV astronomy in the first place, and led to the development of the atmospheric Cherenkov technique; significant progress has been made in the last decade through the detection of several supernova remnants, the primary suspects for harboring the acceleration sites of cosmic rays. TeV γ-rays propagate mostly unhindered through the galactic plane,

APA, Harvard, Vancouver, ISO, and other styles

17

Popescu, Adrian. "Hubble’S Law in the Local Flat Spacetime." Romanian Astronomical Journal 34, no. 1-2 (2024): 3–14. http://dx.doi.org/10.59277/roaj.2024.1-2.01.

Full text

Abstract:

On the road towards observational (and experimental) validation of the DEUS cosmological model we will cross the boundary between theory and observation with the help of Hubble’s law for the Universe evolution, expressed as function of quantities as redshift z (measured through Doppler-shift observations) and local time T. In the book by Popescu (2007) we gave a theoretical method for computing the Hubble constant H0. Now, in the light of the new acquired knowledge that followed Popescu (2020) paper’s results, after defining what is the local time for the flat spacetime and how it relates to t

APA, Harvard, Vancouver, ISO, and other styles

18

Wasserburg, G. J., and Y. Z. Qian. "Chemical Evolution of the Juvenile Universe." Publications of the Astronomical Society of Australia 26, no. 3 (2009): 184–93. http://dx.doi.org/10.1071/as08058.

Full text

Abstract:

AbstractModels of average Galactic chemical abundances are in good general agreement with observations for [Fe/H] > –1.5, but there are gross discrepancies at lower metallicities. Only massive stars contribute to the chemical evolution of the ‘juvenile universe’ corresponding to [Fe/H] ≲ –1.5. If Type II supernovae (SNe II) are the only relevant sources, then the abundances in the interstellar medium of the juvenile epoch are simply the sum of different SN II contributions. Both low-mass (∼8–11 M⊙) and normal (∼12–25 M⊙) SNe II produce neutron stars, which have intense neutrino-driven winds

APA, Harvard, Vancouver, ISO, and other styles

19

Schmidt, Brian P. "The Expanding and Accelerating Universe." International Astronomical Union Colloquium 192 (2005): 511–23. http://dx.doi.org/10.1017/s0252921100009611.

Full text

Abstract:

SummaryMeasuring distances back to a significant portion of the look back time probes the make-up of the Universe, through the effects of different types of matter on the cosmological geometry and expansion. Over the past five years two teams have used type Ia supernovae to trace the expansion of the Universe to a look back time more than 70% of the age of the Universe. These observations show an accelerating Universe which is best explained by a cosmological constant, or other form of dark energy with an equation of state near w = p/ρ = −1. There are many possible lurking systematic effects.

APA, Harvard, Vancouver, ISO, and other styles

20

Bolejko, K. "Light propagation through large-scale inhomogeneities in the Universe and its impact on cosmological observations." EAS Publications Series 30 (2008): 349–52. http://dx.doi.org/10.1051/eas:0830059.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Baquero Larriva, A., and J. L. Contreras. "Exploring the Universe through Gamma-Ray Astronomy: Characterization and Performance of the LST-1 Telescope." Journal of Physics: Conference Series 2796, no. 1 (2024): 012008. http://dx.doi.org/10.1088/1742-6596/2796/1/012008.

Full text

Abstract:

Abstract Gamma-ray astronomy allows for the exploration of the most energetic phenomena in the universe and has seen significant advances in the 21st century, as evidenced by the development of the LST-1 telescope, a part of the Cherenkov Telescope Array (CTA). The LST-1, situated at the Roque de los Muchachos Observatory in La Palma, Spain, commenced its commissioning phase in October 2018 and captured its first light in December of the same year. This research primarily addresses the characterization of the LST-1 telescope, utilizing Monte Carlo simulations and real data from observations of

APA, Harvard, Vancouver, ISO, and other styles

22

Dai, Baochen. "Analysis Of the Principe, Facility and Applications for Gravitation Wave Searching." Highlights in Science, Engineering and Technology 112 (August 20, 2024): 210–15. http://dx.doi.org/10.54097/h98jef45.

Full text

Abstract:

Gravitational wave detection has become a crucial tool in understanding the universe, with applications in the origin of the universe, black hole physics, galaxy evolution, and more. Researchers have used gravitational wave research to explore dark matter, dark energy, and other enigmatic phenomena, offering new insights into the evolution of the universe. This study will systematically analyze the principle as well as the state-of-art facilities and applications for gravitational wave searching. The similarities between gravitational waves and electromagnetic waves suggest that detecting grav

APA, Harvard, Vancouver, ISO, and other styles

23

Ciardi, Benedetta. "Cosmic re-onization: theoretical modelling and forthcoming observations." Proceedings of the International Astronomical Union 2, no. 14 (2006): 380–81. http://dx.doi.org/10.1017/s1743921307011088.

Full text

Abstract:

AbstractWith the advent in the near future of radio telescopes such as LOFAR and the SKA, a new window on the high-redshift Universe will be opened. In particular, it will be possible, for the first time, to observe the 21-cm signal from the diffuse IGM prior to its complete re-ionization and thus probe the ‘dark ages’. I discuss the theoretical modelling of the re-ionization process and its observability through the 21-cm signal and the CMB anisotropies.

APA, Harvard, Vancouver, ISO, and other styles

24

Tian, Tian. "Study of stellar properties under TESS satellite observations." Theoretical and Natural Science 43, no. 1 (2024): 6–14. http://dx.doi.org/10.54254/2753-8818/43/20240956.

Full text

Abstract:

This study employs data from the TESS satellite to investigate the properties of stars. TESS, the Transiting Exoplanet Survey Satellite, offers insights into star activity, periodic variations, and planetary transits by monitoring changes in stellar brightness. Our analysis of TESS data explores critical star attributes, including mass, luminosity, activity levels, and dynamic changes. By examining the relationship between these stellar properties and the presence of planets, we aim to uncover the intricate interplay between celestial bodies and unveil the universe's mysteries. This research e

APA, Harvard, Vancouver, ISO, and other styles

25

Lépine-Szily, Alinka, and Pierre Descouvemont. "Nuclear astrophysics: nucleosynthesis in the Universe." International Journal of Astrobiology 11, no. 4 (2012): 243–50. http://dx.doi.org/10.1017/s1473550412000158.

Full text

Abstract:

AbstractNuclear astrophysics is a relatively young science; it is about half a century old. It is a multidisciplinary subject, since it combines nuclear physics with astrophysics and observations in astronomy. It also addresses fundamental issues in astrobiology through the formation of elements, in particular those required for a carbon-based life. In this paper, a rapid overview of nucleosynthesis is given, mainly from the point of view of nuclear physics. A short historical introduction is followed by the definition of the relevant nuclear parameters, such as nuclear reaction cross sections

APA, Harvard, Vancouver, ISO, and other styles

26

Deng, Junyue. "Research on Conjecture of Dark Energy." Theoretical and Natural Science 79, no. 1 (2025): 109–13. https://doi.org/10.54254/2753-8818/2025.19929.

Full text

Abstract:

An in-depth exploration of the origin of dark energy is undertaken. Dark energy is a fascinating and mysterious concept within the realm of astrophysics. It was discovered through a series of astronomical observations and theoretical studies. For instance, the observation of distant supernovae revealed the accelerating expansion of the universe, leading to the postulation of an unknown forcedark energy. The crucial role played by dark energy in the universe is then delved into. It is now widely accepted that dark energy is responsible for accelerating the expansion of the universe. This has si

APA, Harvard, Vancouver, ISO, and other styles

27

ZHANG, Tianxi. "GENESIS AND BLACK HOLE UNIVERSE:THE FOURTH DAY." International Journal of Theology, Philosophy and Science 5, no. 9 (2021): 5–18. http://dx.doi.org/10.26520/ijtps.201.5.9.5-18.

Full text

Abstract:

Papers I through III has fully and self-consistently addressed the first three days of Genesis according to the author’s well-developed black hole universe model. In the first day, God created space and time, matter and motion, charge and fundamental forces, and energy and light for the infinite entire universe. Then, in the second day he hierarchically structured the entire universe by separating the matter and space with infinite layers bounded by event horizons and further formed our finite black hole universe. In the third day, God constructed the interiors of our black hole universe with

APA, Harvard, Vancouver, ISO, and other styles

28

RINALDI, MASSIMILIANO. "ASPECTS OF QUANTUM GRAVITY IN COSMOLOGY." Modern Physics Letters A 27, no. 07 (2012): 1230008. http://dx.doi.org/10.1142/s021773231230008x.

Full text

Abstract:

We review some aspects of quantum gravity in the context of cosmology. In particular, we focus on models with a phenomenology accessible to current and near-future observations, as the early Universe might be our only chance to peep through the quantum gravity realm.

APA, Harvard, Vancouver, ISO, and other styles

29

ZHANG, Tianxi. "THE FIRST FOUR DAYS: A SCIENTIFIC VIEW FOR THE CREATION OF THE UNIVERSE." International Multidisciplinary Scientific Conference on the Dialogue between Sciences & Arts, Religion & Education 5, no. 1 (2021): 58–66. http://dx.doi.org/10.26520/mcdsare.2021.5.58-66.

Full text

Abstract:

The first four days of Genesis are scientifically interpreted according to the author’s well-developed black hole universe model. From this scientific view for the creation of the universe described in the book of Genesis, God in the first day created the space and time, matter and motion, charge and fundamental forces, energy and light for the infinite large entire universe. Then, in the second day, God hierarchically structured the entire universe by separating the matter and space with infinite layers that are bounded by event horizons and further formed our finite black hole universe. In t

APA, Harvard, Vancouver, ISO, and other styles

30

Dyer, Charles C. "Gravitational lenses and the inhomogeneous universe." Canadian Journal of Physics 64, no. 2 (1986): 160–64. http://dx.doi.org/10.1139/p86-027.

Full text

Abstract:

The theory of static gravitatonal lenses is discussed using the optical scalar formalism and the ray-bending approximation to this formalism. The advantages of each approach are discussed, with particular emphasis on the use of the bending approximation for discretely observable lenses, say multiply imaged quasars, and the optical scalar equations for cumulative effects of inhomogeneities for distant objects in the universe.The effect of a locally lumpy distribution on the past null cone of a typical observer is discussed. This is of particular interest in deciding the limits to which one can

APA, Harvard, Vancouver, ISO, and other styles

31

Trang, Nguyen Thi Thao, Peter Lott, and Quynh Lan Nguyen. "Magnetic Field in the Universe." Journal of Physics: Conference Series 3040, no. 1 (2025): 012009. https://doi.org/10.1088/1742-6596/3040/1/012009.

Full text

Abstract:

Abstract Magnetic fields permeate the universe and influence physical processes, from compact objects to large cosmic structures. Unlike electric fields, magnetic fields are closely tied to space-time dynamics, governing charged particle motion and producing radiation such as synchrotron and curvature emission. On intergalactic scales, magnetic fields are reshaped during galaxy mergers. Gravitational forces drive turbulence, shock waves, and gas inflows that amplify and reorganize magnetic fields. Radio synchrotron emission and polarization mapping observations reveal strong, coherent fields i

APA, Harvard, Vancouver, ISO, and other styles

32

Paul, BC. "Dark Matter and Dark Energy in the Universe." BIBECHANA 11 (May 8, 2014): 8–16. http://dx.doi.org/10.3126/bibechana.v11i0.10374.

Full text

Abstract:

Cosmological and astronomical observations predict that the present Universe is passing through an accelerating phase of expansion. The Universe emerged out of an exponential phase in the very early Universe. The scalar field of the standard model of particle physics when used in cosmology admits such a phase of expansion known as inflation. The most favourable condition for inflation with scalar field to admit an Inflationary scenario is that the potential energy must dominate over the kinetic energy which one obtains with a flat potential. Thereafter the Universe enters into a matter dominat

APA, Harvard, Vancouver, ISO, and other styles

33

Feng, Haoyang. "Integrated study of dark matter and dark energy models." Theoretical and Natural Science 34, no. 1 (2024): 162–71. http://dx.doi.org/10.54254/2753-8818/34/20241173.

Full text

Abstract:

Dark matter and dark energy are used as two important concepts in cosmology to explain some of the observed phenomena in the universe. Dark matter is one of the most dominant constituents of the Universe, and it influences the structural formation of the Universe through gravity, including the formation and evolution of galaxies, clusters, and the large-scale structure of the Universe. Dark energy is believed to be one of the causes of the accelerated expansion of the Universe, and its presence explains the observed phenomenon of the accelerating rate of expansion of the Universe. Although the

APA, Harvard, Vancouver, ISO, and other styles

34

Potter, Shannon, and Luis Lehner. "Distinguishing black holes through their ringing." SURG Journal 4, no. 1 (2010): 87–92. http://dx.doi.org/10.21083/surg.v4i1.1201.

Full text

Abstract:

A perturbed black hole spacetime emits gravitational waves possessing quasinormal modes that are characteristic of the black hole itself. We use a massless scalar field as an analog to a gravitational wave to find the quasinormal modes emitted by both a Schwarzschild black hole and a new alternative black hole model which places the Schwarzschild black hole in an aether—a zero density, negative pressure perfect fluid. The later model was proposed as an alternative explanation for accelerated cosmic expansion [1]. We construct a computational code to study both systems numerically and obtain th

APA, Harvard, Vancouver, ISO, and other styles

35

Lagache, Guilaine. "Exploring the dusty star-formation in the early Universe using intensity mapping." Proceedings of the International Astronomical Union 12, S333 (2017): 228–33. http://dx.doi.org/10.1017/s1743921318000558.

Full text

Abstract:

AbstractIn the last decade, it has become clear that the dust-enshrouded star formation contributes significantly to early galaxy evolution. Detection of dust is therefore essential in determining the properties of galaxies in the high-redshift universe. This requires observations at the (sub-)millimeter wavelengths. Unfortunately, sensitivity and background confusion of single dish observations on the one hand, and mapping efficiency of interferometers on the other hand, pose unique challenges to observers. One promising route to overcome these difficulties is intensity mapping of fluctuation

APA, Harvard, Vancouver, ISO, and other styles

36

Jara Murillo, Carla Victoria. "Análisis componencial del parentesco en Bocota de Chiriquí." Revista de Filología y Lingüística de la Universidad de Costa Rica 15, no. 2 (2015): 131. http://dx.doi.org/10.15517/rfl.v15i2.19377.

Full text

Abstract:

Este artículo es una compilación de términos de parentesco en el idioma Bocota (Chiriquí dialecto) de Panamá. Estos lexemas se analizan y definen a través del análisis componencial y posibles paradigmas se configuran en el universo total de las relaciones de parentesco. Incluido son observaciones y datos en relación con el sistema de parentesco y las costumbres familiares de la Bocotás.This article is a compilation of kinship terms in the Bocotá language (Chiriquí dialect) of Panama. These lexemes are analyzed and defined through componential analysis, and possible paradigms are set up in the

APA, Harvard, Vancouver, ISO, and other styles

37

Salati, Pierre. "Dark matter annihilation in the universe." International Journal of Modern Physics: Conference Series 30 (January 2014): 1460256. http://dx.doi.org/10.1142/s2010194514602567.

Full text

Abstract:

The astronomical dark matter is an essential component of the Universe and yet its nature is still unresolved. It could be made of neutral and massive elementary particles which are their own antimatter partners. These dark matter species undergo mutual annihilations whose effects are briefly reviewed in this article. Dark matter annihilation plays a key role at early times as it sets the relic abundance of the particles once they have decoupled from the primordial plasma. A weak annihilation cross section naturally leads to a cosmological abundance in agreement with observations. Dark matter

APA, Harvard, Vancouver, ISO, and other styles

38

Jawad, Abdul, and Abdul Malik Sultan. "Cosmic Consequences of Kaniadakis and Generalized Tsallis Holographic Dark Energy Models in the Fractal Universe." Advances in High Energy Physics 2021 (April 20, 2021): 1–12. http://dx.doi.org/10.1155/2021/5519028.

Full text

Abstract:

We investigate the recently proposed holographic dark energy models with the apparent horizon as the IR cutoff by assuming Kaniadakis and generalized Tsallis entropies in the fractal universe. The implications of these models are discussed for both the interacting ( Γ = 3 H b 2 ρ m ) and noninteracting ( b 2 = 0 ) cases through different cosmological parameters. Accelerated expansion of the universe is justified for both models through deceleration parameter q . In this way, the equation of state parameter ω d describes the phantom and quintessence phases of the universe. However, the coincide

APA, Harvard, Vancouver, ISO, and other styles

39

Hansen, Steen H. "Accelerated expansion induced by dark matter with two charges." Monthly Notices of the Royal Astronomical Society: Letters 508, no. 1 (2021): 22–25. http://dx.doi.org/10.1093/mnrasl/slab103.

Full text

Abstract:

ABSTRACT The accelerated expansion of the Universe has been established through observations of supernovae, the growth of structure, and the cosmic microwave background. The most popular explanation is Einstein's cosmological constant, or dynamic variations hereof. A recent paper demonstrated that if dark matter particles are endowed with a repulsive force proportional to the internal velocity dispersion of galaxies, then the corresponding acceleration of the Universe may follow that of a cosmological constant fairly closely. However, no such long-range force is known to exist. A concrete exam

APA, Harvard, Vancouver, ISO, and other styles

40

Yadav, Bal Krishna, and Murli Manohar Verma. "Cosmological wheel of time: A classical perspective of f(R) gravity." International Journal of Modern Physics D 27, no. 01 (2017): 1750183. http://dx.doi.org/10.1142/s0218271817501838.

Full text

Abstract:

It is shown that the structures in the universe can be interpreted to show a closed wheel of time, rather than a straight arrow. An analysis in [Formula: see text] gravity model has been carried out to show that due to local observations, a small arc at any given spacetime point would invariably indicate an arrow of time from past to future, though on a quantum scale it is not a linear flow but a closed loop, a fact that can be examined through future observations.

APA, Harvard, Vancouver, ISO, and other styles

41

Faucher, Nicholas, Michael R. Blanton, and Andrea V. Macciò. "Panchromatic Simulated Galaxy Observations from the NIHAO Project." Astrophysical Journal 957, no. 1 (2023): 7. http://dx.doi.org/10.3847/1538-4357/acf9f0.

Full text

Abstract:

Abstract We present simulated galaxy spectral energy distributions (SEDs) from the far-ultraviolet (FUV) through the far-infrared (FIR), created using hydrodynamic simulations and radiative transfer calculations, suitable for the validation of SED modeling techniques. SED modeling is an essential tool for inferring star formation histories from nearby galaxy observations, but it is fraught with difficulty due to our incomplete understanding of stellar populations, chemical enrichment processes, and the nonlinear, geometry-dependent effects of dust on our observations. Our simulated SEDs will a

APA, Harvard, Vancouver, ISO, and other styles

42

Chavanis, Pierre-Henri. "A Real Scalar Field Unifying the Early Inflation and the Late Accelerating Expansion of the Universe through a Quadratic Equation of State: The Vacuumon." Universe 8, no. 2 (2022): 92. http://dx.doi.org/10.3390/universe8020092.

Full text

Abstract:

In a previous paper we introduced a cosmological model describing the early inflation, the intermediate decelerated expansion, and the late accelerating expansion of the universe in terms of a single barotropic fluid characterized by a quadratic equation of state. We obtained a scalar field representation of this fluid and determined the potential V(ϕ) connecting the inflaton potential in the early universe to the quintessence potential in the late universe. This scalar field has later been called the ‘vacuumon’ by other authors, in the context of the Running Vacuum model. In this paper, we st

APA, Harvard, Vancouver, ISO, and other styles

43

Nanayakkara, Themiya, Karl Glazebrook, Colin Jacobs, et al. "Early Results from GLASS-JWST. XVI. Discovering a Bluer z ∼ 4–7 Universe through UV Slopes." Astrophysical Journal Letters 947, no. 2 (2023): L26. http://dx.doi.org/10.3847/2041-8213/acbfb9.

Full text

Abstract:

Abstract We use the GLASS-JWST Early Release Science NIRCam parallel observations to provide a first view of the UV continuum properties of NIRCam/F444W selected galaxies at 4 < z < 7. By combining multiwavelength NIRCam observations, we constrain the UV continuum slope for a sample of 401 galaxies with stringent quality controls. We find that >99% of the galaxies are blue star-forming galaxies with very low levels of dust (Av β ∼ 0.01 ± 0.33). We find no statistically significant correlation for UV slope with redshift or UV magnitude. However, we find that in general galaxies at high

APA, Harvard, Vancouver, ISO, and other styles

44

Garg, Pryanka, Rashid Zia, and Anirudh Pradhan. "Transit cosmological models in FRW universe under the two-fluid scenario." International Journal of Geometric Methods in Modern Physics 16, no. 01 (2019): 1950007. http://dx.doi.org/10.1142/s0219887819500075.

Full text

Abstract:

This paper is an attempt to revisit the Friedmann–Robertson–Walker (FRW) cosmological models under the new scenario of observational cosmology, which has established that the current universe is expanding with an increasing rate, in contrast to the earlier belief that the rate of expansion is constant or slowing down. This paper represents a model which encompasses both, earlier decelerating and the current accelerating universe, passing through a transition phase. The universe is assumed to be filled with two fluids, barotropic and dark energy. We have considered two cases; first, when these

APA, Harvard, Vancouver, ISO, and other styles

45

Motavalli, H., A. Rezaei Akbarieh, and M. Nasiry. "Kantowski–Sachs cosmological solutions in the generalized teleparallel gravity via Noether symmetry." Modern Physics Letters A 31, no. 15 (2016): 1650095. http://dx.doi.org/10.1142/s0217732316500954.

Full text

Abstract:

We study the f(T) theory as an extension of teleparallel gravity and consider the Noether symmetry of Kantowski–Sachs (KS) anisotropic model for this theory. We specify the explicit teleparallel form of f(T) and find the corresponding exact cosmological solutions under the assumption that the Lagrangian admits the Noether symmetry. It is found that the universe experiences a power law expansion for the scale factors in the context of f(T) theory. By deriving equation of state (EOS) parameter, we show that the universe passes through the phantom and [Formula: see text]CDM theoretical scenarios.

APA, Harvard, Vancouver, ISO, and other styles

46

Xie, Youmeng. "Analysis Of Black Hole Merger from Gravitational Wave Generation and Observation." Highlights in Science, Engineering and Technology 112 (August 20, 2024): 7–14. http://dx.doi.org/10.54097/154ck245.

Full text

Abstract:

Currently, one of the main areas of interest for astronomical study is the monitoring of black hole merger events, thanks to the development of gravitational wave astronomy. Human beings now have the chance to go deeper into the cosmos thanks to this field's quick progress, particularly in terms of comprehending astrophysical processes under extremely strong gravitational fields. A detailed examination of the production and detection of gravitational waves during black hole mergers is the focus of this study. To gain a deeper knowledge of the phenomenon of black hole mergers in the universe, t

APA, Harvard, Vancouver, ISO, and other styles

47

Xu, Padi. "Analysis of Category and the State-of-art Observations of Black Holes." Highlights in Science, Engineering and Technology 72 (December 15, 2023): 1373–77. http://dx.doi.org/10.54097/5azjds02.

Full text

Abstract:

As a matter of fact, black holes observation and investigation is one of the most mysterious part of astrophysics and cosmology. With the rapid development of techniques, high accuracy observation and detection are available based on the state-of-art facilities and detectors. With this in mind, this research paper aims to delves into all aspects of black holes, including their formation, properties, singularities, gravitational effects, and effects on the universe and matter. The mysterious and captivating nature of black holes has sparked an immense amount of interest in theoretical physics a

APA, Harvard, Vancouver, ISO, and other styles

48

Gede, Yoga Kharisma Pradana. "ANIMO DOSEN STPBI DALAM GERAKAN SEMESTA BERENCANA BALI RESIK SAMPAH PLASTIK DI KARANGASEM, BALI." SWARNA: Jurnal Pengabdian Kepada Masyarakat 1, no. 3 (2022): 245–55. http://dx.doi.org/10.55681/swarna.v1i3.115.

Full text

Abstract:

The purpose of writing this article is to publish an achievement of community service activities in Karangasem. Generally, the enthusiasm of the STPBI Lecturers is seen in tourism, hospitality, and education events. However, it turns out that there is an interest from STPBI lecturers in the Bali Resik Plastic Waste Planning Universe Movement in Karangasem. The problems are: 1) What is the structure of the Bali Planned Universe Movement for Recycling Plastic Waste in Karangasem? 2) What are the STPBI Lecturers' animo on the Bali Planned Universe Movement to Clean Up Plastic Waste in Karangasem?

APA, Harvard, Vancouver, ISO, and other styles

49

Kasuya, Shinta, Masahiro Kawasaki, and Kai Murai. "Enhancement of second-order gravitational waves at Q-ball decay." Journal of Cosmology and Astroparticle Physics 2023, no. 05 (2023): 053. http://dx.doi.org/10.1088/1475-7516/2023/05/053.

Full text

Abstract:

Abstract The recent observation of 4He favors a large lepton asymmetry at the big bang nucleosynthesis. If Q-balls with a lepton charge decay after the electroweak phase transition, such a large lepton asymmetry can be generated without producing too large baryon asymmetry. In this scenario, Q-balls dominate the universe before the decay and induces the sharp transition from the early matter-dominated era to the radiation-dominated era. In this transition, the gravitational waves (GWs) are enhanced through a second-order effect of the scalar perturbations. We evaluate the density of the produc

APA, Harvard, Vancouver, ISO, and other styles

50

Tolasa, Diriba. "Atomic and Molecular Physics in Astrophysics: Probing the Universe Through Spectroscopic Techniques." World Journal of Applied Physics 10, no. 1 (2025): 28–34. https://doi.org/10.11648/j.wjap.20251001.13.

Full text

Abstract:

The interplay between atomic and molecular physics and astrophysics is critical for advancing the understanding of the universe. This paper investigates the significance of spectroscopic techniques in probing celestial phenomena, emphasizing their role in revealing the composition, temperature, density, and motion of astronomical objects. By analyzing the spectral lines emitted or absorbed by various elements and molecules, researchers can derive essential insights into the physical conditions prevailing in stars, galaxies, and interstellar media. Recent advancements in high-resolution spectro

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!