자료유형  

 학위논문

Control Number  

0017165199

International Standard Book Number  

9798346384694

Dewey Decimal Classification Number  

300

Main Entry-Personal Name  

Wang, Yunchong.

Publication, Distribution, etc. (Imprint  

[S.l.] : Stanford University., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

325 p.

General Note  

Source: Dissertations Abstracts International, Volume: 86-05, Section: B.

General Note  

Advisor: Wechsler, Risa.

Dissertation Note  

Thesis (Ph.D.)--Stanford University, 2024.

Summary, Etc.  

요약Understanding the cosmos is a fundamental urge buried in humans, the urge to know the answer of where we came from and where we will go. Our view of the Universe encountered a major paradiagm shift in the early 20thcentury from a static Universe (Newton's theory) to an expanding Universe with the measurement of the Hubble's Law [213]. In such a Universe, rewinding time backwards would bring every point in the Universe back to a singularity where time began, the Big Bang [267]. Subsequent pivotal discoveries of the Cosmic Microwave Background [CMB, 366, 361, 42, 43, 376, 377], the abundance of light elements [98], and the Large Scale Structure of the Universe [106, 147, 534, 438, 2, 85] further consolidated the origin of the Universe from the Big Bang.In this expanding Universe, cold and hot patches in the CMB provide initial perturbations to overdense and underdense regions in the matter distribution as the Universe cools. The overdense perturbations subsequently collapse under gravity and form the large scale structure of the Universe, while underdense perturbations become voids. Since Vera Rubin's first measurement of the rotation curves of nearby galaxies [403] being far from Keplerian, it is known that luminous matter, a.k.a standard model particles [baryons, 2], only make up ≲ 20% of the total matter content in the Universe that can cause gravitational effects. The other ≳ 80% of matter, a.k.a. dark matter, behaves like a collisionless ideal gas and does not interact with light [latest dark matter-baryon interaction upper limits from 1]. The presence of dark matter at significant proportions however is highly-confident, due to its capability to simultaneously explain the angular correlation of the CMB, the rotation curves of galaxies, the spatial clustering of galaxies especially the Baryonic Acoustic Oscillations, BAO [133, 367, 107], and the presence of strong and weak gravitational lenses [e.g., 341].Galaxies, i.e.,ensembles of stars, have been the main luminous tracers of the elusive dark matter in the Universe. In modern definitions, the key difference between a galaxy and a star cluster [258, 182] is that the former is gravitationally bound by a dark matter halo and the later is bound by the selfgravity of stars and gas only. In the 1980s, there were two competing theories of dark matter that argued for opposite structure formation scenarios. In the case of hot or warm dark matter [59, 61], ultra-light particles like neutrinos constitutes the bulk mass of dark matter and would free stream at relativistic velocities in the early Universe, suppressing small scale structures [59]. The largest galaxy clusters would form first before fragmenting into smaller galaxies in a 'top down' fashion. In the cold dark matter (CDM) scenario [363, 58], the opposite happens as dark matter has negligible streaming velocity and primordial overdensities from the CMB can quickly collapse into small dark matter halos before hierarchically merging into larger galaxies in a 'bottom up' fashion. This model has shown agreements with the large-scale matter density distribution observations. It was also further corroborated by the COBE small scale CMB power spectrum [42] at about the same time that the 'bottom up' scenario was shown to be more favorable, with CDM pulling away as the leading dark matter theory.

Subject Added Entry-Topical Term  

Stars & galaxies.

Subject Added Entry-Topical Term  

Astrophysics.

Subject Added Entry-Topical Term  

Star & galaxy formation.

Subject Added Entry-Topical Term  

Space telescopes.

Subject Added Entry-Topical Term  

Satellites.

Subject Added Entry-Topical Term  

Aerospace engineering.

Subject Added Entry-Topical Term  

Astronomy.

Subject Added Entry-Topical Term  

Optics.

Added Entry-Corporate Name  

Stanford University.

Host Item Entry  

Dissertations Abstracts International. 86-05B.

Electronic Location and Access  

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Control Number  

joongbu:655400