本文關(guān)鍵詞：強(qiáng)引力透鏡系統(tǒng)限制宇宙學(xué)模型　出處：《大連理工大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 強(qiáng)引力透鏡 觀測限制 暗能量 模型參數(shù)

【摘要】：1998年,基于兩個小組對Ia型超新星觀測的證據(jù)表明,我們的宇宙當(dāng)前正處于一個所謂的“后期加速膨脹”階段,揭示出這個加速膨脹背后的機(jī)制成為21世紀(jì)宇宙學(xué)最重要的任務(wù)之一。目前,對于宇宙加速膨脹有兩種詮釋路徑,分別是暗能量假說和大尺度上的修改引力理論。具有負(fù)壓強(qiáng)的暗能量假說是建立在對愛因斯坦廣義相對論信任的基礎(chǔ)上的,甫一提出便引起了廣大研究者們的關(guān)注,持這種觀點(diǎn)的人們認(rèn)為正是暗能量的負(fù)壓強(qiáng)為宇宙加速膨脹提供了動力。此外,從宇宙的組成成分上來看,最新的觀測數(shù)據(jù)顯示,普通物質(zhì)占宇宙組分的4%,影響宇宙演化和大尺度結(jié)構(gòu)形成的暗物質(zhì)占28%,為宇宙加速膨脹提供驅(qū)動力的暗能量占68%,其中后兩者都是不與光相互作用(看不見)的暗成分,由此數(shù)據(jù)我們確信暗成分對宇宙演化起到了決定性作用,而我們恰恰對它們知之甚少。為了破解這個僵局,揭開暗能量的神秘面紗并進(jìn)一步解釋宇宙后期加速膨脹現(xiàn)象,宇宙學(xué)家們做了很多努力。在理論方面,提出了各種各樣唯象的暗能量模型。其中把暗能量狀態(tài)方程參數(shù)化或者常數(shù)化的ωCDM模型作為標(biāo)準(zhǔn)的基于宇宙學(xué)常數(shù)的ACDM模型的簡單推廣,在理論上具有重要研究價值。觀測方面,強(qiáng)引力透鏡作為宇宙學(xué)領(lǐng)域的一顆新星正在受到越來越廣泛的重視。當(dāng)前來自多個觀測項(xiàng)目的強(qiáng)引力透鏡系統(tǒng)數(shù)據(jù)已達(dá)到118組,研究它們對暗能量模型的限制是一件很有意義的工作。本文的主要工作就是利用118組強(qiáng)引力透鏡系統(tǒng)來限制暗能量狀態(tài)方程為常數(shù)的wCDM模型。利用馬爾可夫鏈-蒙特卡洛(MCMC)方法,對宇宙學(xué)參數(shù)和透鏡模型參數(shù)進(jìn)行擬合,得到了相對緊致的參數(shù)空間,驗(yàn)證了宇宙學(xué)參數(shù)與強(qiáng)引力透鏡模型之間的依賴關(guān)系,并討論了冪律模型中冪律指數(shù)7的兩種參數(shù)化形式對宇宙學(xué)參數(shù)的影響。本文具體分為三章,我們的主要工作放在了第三章。在第一章我們闡述了必要的背景宇宙學(xué)知識,使得我們能夠無障礙地在后續(xù)部分展開對強(qiáng)引力透鏡的介紹,主要包括宇宙背景動力學(xué)演化相關(guān)的知識,觀測中常用的紅移和角直徑距離的概念,以及幾種流行的暗能量模型。在第二章中,我們介紹強(qiáng)引力透鏡的基本理論,首先假設(shè)強(qiáng)引力透鏡可以近似為奇異等溫球(SIS)模型,進(jìn)一步我們推廣到更一般化的冪律密度(PLP)模型,并給出模型理論與觀測之間的數(shù)學(xué)關(guān)系。在第三章中我們用來自SLACS、BELLS、LSD和SL2S的118組強(qiáng)引力透鏡系統(tǒng)限制wCDM模型。角直徑距離的比值Dobs= D(zl,zs)/D(O,zs)作為宇宙學(xué)觀測量,通過MCMC方法,擬合得出最優(yōu)的模型參數(shù)空間并給出對結(jié)果的分析。本文的最后部分是我們的總結(jié)。
[Abstract]:In 1998, two groups of observations of type Ia supernovae based on the evidence that our universe is currently in a so-called "accelerated expansion" stage, revealing the mechanism behind this acceleration has become one of the most important tasks of cosmology in twenty-first Century. At present, the accelerated expansion of universe two interpretation path, respectively. Is dark energy hypothesis and large scales. The modified gravity theory has dark energy negative pressure hypothesis is based on Einstein's theory of general relativity on the basis of trust, was proposed, has aroused widespread attention of researchers, people who hold this view that it is the negative pressure of dark energy is accelerating expansion of the universe provide power. In addition, from the point of view of the composition of the universe, the latest observations showed that ordinary matter component of the universe 4%, affecting the formation of large scale structure of the universe and the evolution of dark matter accounts for 28 %, provide the driving force of the dark energy accounted for 68% of the accelerating expansion of the universe, after which both are not interact with light (invisible) dark component, the data on the evolution of the universe, we are sure that the dark component plays a decisive role, and we just know little about them. In order to break this impasse. Mysterious dark energy and further explain the late acceleration phenomenon, astronomers have made a lot of efforts. In the theoretical aspect, put forward various phenomenological models of dark energy. The dark energy equation of state parameters or constants of the Omega CDM model as the standard simple extension of the ACDM model of the cosmological constant based on the important research value in theory. Observation, strong lensing as a new star in the field of cosmology is attracted more and more attention. The strong gravity from multiple projects through observation Mirror system data has reached 118, on the restriction of the dark energy model is a very meaningful work. The main work of this paper is to use 118 sets of strong gravitational lens systems to limit the dark energy equation of state for wCDM model constant. Using Markov chain Monte Carlo (MCMC) method to fit the cosmological parameters the lens and the parameters of the model, get the parameter space is relatively compact, verify the dependencies between the cosmological parameters and strong lensing model, and discussed the effects of two kinds of parametric form of the power-law index of the power law model of the universe in 7 parameters. This paper is divided into three chapters, the main work we put in in the third chapter. In the first chapter, we elaborate the necessary background knowledge of cosmology, so that we can start without hindrance on strong gravitational lensing in the subsequent introduction part, mainly includes the dynamic background of the universe The evolution of knowledge, redshift and the angular diameter distance of the common concept of observation, and several popular models of dark energy. In the second chapter, we introduce the basic theory of strong gravitational lensing, assuming strong lensing can approximate the singular isothermal sphere (SIS) model, we further extended to power-law density generalized (PLP) model, the mathematical relationship between model theory and observation was given. In the third chapter we use from SLACS, BELLS, LSD and SL2S of the 118 groups of strong gravitational lens system to limit the wCDM model. The angular diameter distance ratio Dobs= D (ZL, ZS) /D (O, ZS) as cosmology the measurements by the MCMC method, the fitting results of the analysis of the results of the optimal model parameter space is given. In the last part of this paper is our summary.

【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：P159

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4 陸W，

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