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"Menguji validitas relativitas umum dapat dilakukan dengan memodifikasinya untuk mencari penyimpangan. Beberapa teori gravitasi termodifikasi menghasilkan potensial gravitasi dengan suku eksponensial yang menyerupai potensial Yukawa untuk aproksimasi medan lemah. Walaupun pengujian eksperimental dari koreksi Yukawa masih terbatas pada skala sistem tata surya, beberapa penelitian terbaru telah menggunakan data dari kurva rotasi galaksi untuk membatasi parameter Yukawa ini secara observasional, namun dengan asumsi bahwa barion terkopel secara lemah dengan gravitasi untuk memenuhi batasan gravitasi lokal. Studi kami mengabaikan asumsi ini dan menganalisis suku koreksi Yukawa baik dalam halo materi gelap maupun komponen bariyonik. Kami menyelidiki empat model: Newton, Almeida, MG, dan MG Duo, berdasarkan keberadaan suku koreksi Yukawa dalam komponennya dan kopling antar jenis partikel. Kami menguji keempat model ini pada tiga set data yang berbeda dari galaksi Bima Sakti, termasuk data Sofue (2015, 2017, dan 2020) dan data kurva rotasi dari Gaia DR3 oleh Wang (2023) dan Zhou (2023). Kami menemukan dukungan statistik yang kuat melalui faktor Bayes untuk model MG Duo yang menunjukkan kopling terpisah antara baryon-baryon dan baryon-DM. Namun, data observasional yang lebih tepat yang mencakup rentang radius galaksi yang lebih luas masih diperlukan untuk meningkatkan pemahaman tentang modifikasi di wilayah dalam galaksi Bima Sakti.

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Testing the validity of general relativity can be done by modifying it to search for potential deviations. Several modified gravity theories introduce a Yukawa-like exponential term in the gravitational potential for weak-field limits. While experimental tests of the Yukawa-correction are limited to Solar system scales, recent studies have used galactic rotation curve data to observationally constrain these Yukawa parameters, although assuming that baryons are weakly coupled to gravity to satisfy local gravity constraints. In our study, we relax this assumption and analyze the Yukawa-correction in both dark matter halo and baryonic components. We investigate four models: Newtonian, Almeida, MG and MG Duo models, based on the presence of the Yukawa-correction term in the components and the coupling between particle species. We tested these models on three Milky Way datasets: Sofue (2015, 2017, 2020) and rotation curves by Wang (2023) and Zhou (2023) derived from Gaia DR3 data. We find strong statistical favor through the Bayes factor for the MG Duo model that presents a separated coupling between baryon-baryon and baryon-DM. However, more precise observational data covering a broader range of galactic radii is still required to enhance our understanding of modifications in the inner regions of the Milky Way."

"ABSTRACTPenulis mempelajari sifat-sifat bintang gelap menggunakan model interaksi diri, model pertukaran meson vektor dan model kondensat Bose-Einstein. Bintang gelap merupakan kumpulan dari materi gelap boson. Materi gelap boson berada dalam keadaan dasar. Sifat-sifat dari bintang gelap yang dipelajari oleh penulis yaitu massa dan jari-jari bintang, deformasi pasang-surut, momen inersia dan hubungan I-Love-Q. Dengan diketahui sifat-sifat tersebut, penulis dapat mengetahui interaksi yang terjadi pada materi gelap boson. Massa materi gelap boson ditetapkan yaitu 300 MeV dan 400 MeV. Nilai konstanta kopling pada model interaksi diri, nilai massa interaksi pada model pertukaran meson vektor dan nilai panjang hamburan pada model kondensat Bose-Einstein diambil dari hasil simulasi numerik materi gelap dingin dan tidak bertumbukan CCDM yang memenuhi persamaan 0.1 ?cm?^2/g le; ?/m_b le;1 ?cm?^2/g.

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ABSTRACTWe study properties of dark stars on self interaction model, exchange vector meson model and Bose Einstein condensate model. Dark stars are compact objects formed from bosonic dark matter. Bosonic dark matter is in ground state. The properties of the dark stars studied by us are the mass and radius of stars, tidal deformation, inertia moment, and I Love Q relation. By knowing these properties, we can see the interactions that occur in bosonic dark matter. Bosonic dark matter mass is set at 300 MeV and 400 MeV. Coupling constant on self interaction model, interaction mass on exchange vector meson model, and scattering length on Bose Einstein condensate model determined by the result of numerical simulations CCDM which requires 0.1 ?cm?^2/g le; ?/m_b le;1 ?cm?^2/g. "

"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."