Hasil Pencarian  ::  Simpan CSV :: Kembali

"A major outstanding problem in physics is understanding the nature of the dark energy that is driving the accelerating expansion of the Universe. This thesis makes a significant contribution by demonstrating, for the first time, using state-of-the-art computer simulations, that the interpretation of future galaxy survey measurements is far more subtle than is widely assumed, and that a major revision to our models of these effects is urgently needed. The work contained in the thesis was used by the WiggleZ dark energy survey to measure the growth rate of cosmic structure in 2011 and had a direct impact on the design of the surveys to be conducted by the European Space Agency's Euclid mission, a 650 million euro project to measure dark energy."

"Pada tesis ini dipelajari objek kompak anisotropik dengan interior diisi dengan dark energy (energi gelap). Objek yang disebut anisotropik, karena tekanan radial dan tangensial di interior objek tidak sama. Untuk memodelkan keadaan energi gelap, digunakan persamaan keadaan Van der Waals dengan parameter bebas ”γ”, “β̅” dan “φ̅”. Perhitungan dilakukan dengan menyelesaikan persamaan Tolman-Oppenheimer￾Volkof (TOV) dimensonless (tidak berdimensi). Di formalisme ini, radius ” ξ” berharga nol hingga satu. Studi yang dilakukan adalah memeriksa jangkauan dari ”γ”, “β̅” dan “φ̅” agar memenuhi objek yang stabil secara fisis. Kestabilan objek kompak ditinjau dari kuadrat kecepatan suara radial dan tangensial. Hasil diperoleh “γ ∈ [0, 0.38]”, “φ̅ ∈ [-0.05, 0]” dan “β̅ ∈ [-0.58, 0]”, untuk memenuhi objek yang stabil. Melalui jangkauan”γ”, “β̅” dan “φ̅” yang diperoleh, ditinjau profil-profil objek.

---

In this thesis, an anisotropic compact object with an interior filled with dark energy is studied. The object is called anisotropic, because the radial and tangential pressures in the interior of the object are not the same. To model the state of dark energy, the Van der Waals equation of state is used with free parameters "γ", "β̅" and "φ̅". The calculation is done by solving the dimensionless Tolman-Oppenheimer-Volkof (TOV) equation. In this formalism, the radius "ξ" has a value of zero to one. The study conducted is to examine the range of "γ", "β̅" and "φ̅" to meet a physically stable object. The stability of the compact object is reviewed from the square of the radial and tangential sound speeds. The results obtained are “γ ∈ [0, 0.38]”, “φ̅ ∈ [-0.05, 0]” and “β̅ ∈ [-0.58, 0]”, to meet the stable object. Through the range of “γ”, “β̅” and “φ̅” obtained, the object profiles are reviewed.."

"Authors Mazure and Le Brun present the inventory of matter, baryonic and exotic, and investigating the nature and fate of matter's twin, anti-matter. They show how technological progress has been a result of basic research, in tandem with the evolution of new ideas, and how the combined effect of these advances might help lift the cosmic veil."

"This book explores the subject in the context of quantum gravity. A novel approach to uncover the dark faces of the standard model of cosmology. The possibility that dark energy and dark matter are manifestations of the inhomogeneous geometry of our universe. On the history of cosmological model building and the general architecture of cosmological modes. Illustrations on the large scale structure of the universe. A new perspective on the classical static Einstein cosmos. Global properties of world models including their topology. The arrow of time in a universe with a positive cosmological constant. Exploring the consequences of a fundamental cosmological constant for our universe. Exploring why the current observed acceleration of the universe may not be its final destiny. Demonstrating that nature forbids the existence of a pure cosmological constant. Our current understanding of the long term (in time scales that greatly exceed the current age of the universe) future of the universe. And the long term fate and eventual destruction of the astrophysical objects that populate the universe, including clusters, galaxies, stars, planets, and black holes."