subject:( Cosmology)

University of Waterloo

1. Sarma Boruah, Supranta. Topics in early and late Universe cosmology.

Degree: 2020, University of Waterloo

► In this thesis, we explore different problems in various areas of cosmology. The inflationary paradigm has been very successful in explaining cosmological observations. However, some… (more)

Subjects/Keywords: cosmology

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APA (6^th Edition):

Sarma Boruah, S. (2020). Topics in early and late Universe cosmology. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/16111

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sarma Boruah, Supranta. “Topics in early and late Universe cosmology.” 2020. Thesis, University of Waterloo. Accessed March 04, 2021. http://hdl.handle.net/10012/16111.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sarma Boruah, Supranta. “Topics in early and late Universe cosmology.” 2020. Web. 04 Mar 2021.

Vancouver:

Sarma Boruah S. Topics in early and late Universe cosmology. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10012/16111.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sarma Boruah S. Topics in early and late Universe cosmology. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/16111

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universitat de Valencia

2. Giusarma, Elena. Testing neutrino physics and dark radiation properties with cosmological measurements .

Degree: 2013, Universitat de Valencia

URL: http://hdl.handle.net/10550/30242

► El Modelo Estándard de partículas fundamentales asume que hay tres especies de neutrinos sin masa que interactúan a través de la fuerza débil. Durante los… (more)

Subjects/Keywords: cosmology

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APA (6^th Edition):

Giusarma, E. (2013). Testing neutrino physics and dark radiation properties with cosmological measurements . (Doctoral Dissertation). Universitat de Valencia. Retrieved from http://hdl.handle.net/10550/30242

Chicago Manual of Style (16^th Edition):

Giusarma, Elena. “Testing neutrino physics and dark radiation properties with cosmological measurements .” 2013. Doctoral Dissertation, Universitat de Valencia. Accessed March 04, 2021. http://hdl.handle.net/10550/30242.

MLA Handbook (7^th Edition):

Giusarma, Elena. “Testing neutrino physics and dark radiation properties with cosmological measurements .” 2013. Web. 04 Mar 2021.

Vancouver:

Giusarma E. Testing neutrino physics and dark radiation properties with cosmological measurements . [Internet] [Doctoral dissertation]. Universitat de Valencia; 2013. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10550/30242.

Council of Science Editors:

Giusarma E. Testing neutrino physics and dark radiation properties with cosmological measurements . [Doctoral Dissertation]. Universitat de Valencia; 2013. Available from: http://hdl.handle.net/10550/30242

University of Canterbury

3. Duley, James. Average cosmic evolution in a lumpy universe.

Degree: MS, Physics, 2011, University of Canterbury

URL: http://dx.doi.org/10.26021/6736

► The procedure of averaging and coarse-graining of the gravitational field equations with sources are investigated in both Newtonian gravity and in general relativity. In particular… (more)

Subjects/Keywords: Cosmology

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APA (6^th Edition):

Duley, J. (2011). Average cosmic evolution in a lumpy universe. (Masters Thesis). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/6736

Chicago Manual of Style (16^th Edition):

Duley, James. “Average cosmic evolution in a lumpy universe.” 2011. Masters Thesis, University of Canterbury. Accessed March 04, 2021. http://dx.doi.org/10.26021/6736.

MLA Handbook (7^th Edition):

Duley, James. “Average cosmic evolution in a lumpy universe.” 2011. Web. 04 Mar 2021.

Vancouver:

Duley J. Average cosmic evolution in a lumpy universe. [Internet] [Masters thesis]. University of Canterbury; 2011. [cited 2021 Mar 04]. Available from: http://dx.doi.org/10.26021/6736.

Council of Science Editors:

Duley J. Average cosmic evolution in a lumpy universe. [Masters Thesis]. University of Canterbury; 2011. Available from: http://dx.doi.org/10.26021/6736

University of New South Wales

4. Zavarygin, Evgeny. Cosmology with quasar spectroscopy.

Degree: Physics, 2020, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/65527 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:64659/SOURCE02?view=true

► Quasar spectroscopy is a unique tool for cosmological studies. Passing through the Universe during billions of years, light from quasars contains information that in some… (more)

▼ Quasar spectroscopy is a unique tool for cosmological studies. Passing through the Universe during billions of years, light from quasars contains information that in some cases cannot be collected in other types of measurements. The recent dramatic improvements in astronomical instrumentation and facilities allow increasingly stringent tests using large sets of high quality spectra. The available spectroscopic quasar data range from high resolution spectra of a relatively small number of objects down to low resolution spectra of a very large number of objects. In this thesis we make use of both types of data to test the standard ΛCDM cosmological model. We use a set of high resolution Keck/HIRES spectra of quasar Q1009+2956 to measure the deuterium abundance (D/H) at high redshift. The previous analysis of the z = 2.504 absorption system towards Q1009+2956 by Burles and Tytler yielded a D/H value greater than is predicted by other measurements. We repeat the analysis using an independent dataset of higher signal-to-noise. The deuterium absorption is found to be contaminated by a previously undetected blend. The analysis results in log D/H = -4.606 +/- 0.066, consistent with other measurements. Using a sample of 13 "reliable" D/H measurements we find the primordial deuterium abundance of (D/H)p = (2.545 +/- 0.025) x 10^-5, consistent with the prediction from the Planck cosmic microwave background analysis. We test the Cosmological Principle by measuring the cosmological distribution of neutral hydrogen over the redshift range 2 < z < 4, probed by the Ly-alpha forest. We use the largest dataset of low resolution quasar spectra available to date, from the SDSS/BOSS survey. A preliminary analysis indicates that a significant anisotropic signal spanning beyond the post-inflation causality scales appears to be present in the data. Taken at face value, this would suggest an anisotropic universe. However, a detailed study reveals sky position dependent systematics such that the data is in fact consistent with isotropy and hence with the standard ΛCDM cosmological model. A thorough investigation of a large number of potential systematic effects is presented. The results of that study should be beneficial in the design of the future large scale surveys such as DESI, 4MOST, WEAVE-QSO, and MSE. Advisors/Committee Members: Webb, John, Physics, Faculty of Science, UNSW, Flambaum, Victor, Physics, Faculty of Science, UNSW.

Subjects/Keywords: Cosmology

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APA (6^th Edition):

Zavarygin, E. (2020). Cosmology with quasar spectroscopy. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/65527 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:64659/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Zavarygin, Evgeny. “Cosmology with quasar spectroscopy.” 2020. Doctoral Dissertation, University of New South Wales. Accessed March 04, 2021. http://handle.unsw.edu.au/1959.4/65527 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:64659/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Zavarygin, Evgeny. “Cosmology with quasar spectroscopy.” 2020. Web. 04 Mar 2021.

Vancouver:

Zavarygin E. Cosmology with quasar spectroscopy. [Internet] [Doctoral dissertation]. University of New South Wales; 2020. [cited 2021 Mar 04]. Available from: http://handle.unsw.edu.au/1959.4/65527 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:64659/SOURCE02?view=true.

Council of Science Editors:

Zavarygin E. Cosmology with quasar spectroscopy. [Doctoral Dissertation]. University of New South Wales; 2020. Available from: http://handle.unsw.edu.au/1959.4/65527 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:64659/SOURCE02?view=true

University of Helsinki

5. Flender, Samuel. Formation of Large-Scale Structure and its Imprint on the Cosmic Microwave Background.

Degree: Department of Physics, 2014, University of Helsinki

URL: http://hdl.handle.net/10138/42877

►

One of the most important aspects of cosmology is the theory of structure formation, which describes the transition from the early, homogeneous Universe to the… (more)

▼

One of the most important aspects of cosmology is the theory of structure formation, which describes the transition from the early, homogeneous Universe to the inhomogeneous Universe we observe today, i.e. the formation of stars, galaxies and clusters of galaxies. In this thesis, we study structure formation using the Newtonian theory of gravity within an expanding Friedmann-Robertson-Walker spacetime. We use this simple framework in order to learn for instance about the order of structure formation, which is a bottom-up evolution. Further, we introduce relativistic cosmological perturbation theory. We show that the Newtonian and relativistic descriptions of linear perturbations coincide on scales that are well inside the horizon. On larger scales however, we find differences between the two theories, in particular in the obtained linear matter power spectra. Observations indicate that the Universe is today in a phase of accelerated expansion. In the standard model of cosmology, the LCDM model, the accelerated expansion is explained by the existence of dark energy in form of a cosmological constant. Here, we focus on the integrated Sachs-Wolfe effect as a probe of the dynamical effects of dark energy. In particular, this effect causes an imprint of the local large-scale structure into the temperature anisotropies of the cosmic microwave background (CMB). We discuss how this effect arises in theory and how it can be measured in practice. The statistical properties of the temperature fluctuations in the CMB can be remarkably well described within the LCDM model. However, on the largest angular scales some features have been found that are difficult to explain within the standard model, the so-called CMB anomalies. Here, we discuss these anomalies from a statistical point of view. We focus on one particular anomaly, the hemispherical power asymmetry, and explore its connection to the initial conditions of the Universe. In particular, this asymmetry can be related to primordial non-Gaussianity in certain inflation models.

Kosmologia on tieteenala joka tutkii maailmankaikkeuden alkuperää, sisältöä ja kehitystä. Nykypäivänä maailmankaikkeus sisältää paljon erilaisia rakenteita, kuten tähtiä, galakseja ja galaksiryppäitä. Toisaalta varhainen maailmankaikkeus oli hyvin homogeeninen. Siirtymää varhaisen, homogeenisen maailmankaikkeuden ja nykyään havaittavan epähomogeenisen maailmankaikkeuden välillä kuvataan rakenteiden muodostumisen teorialla. Rakenteen muodostuminen kattaa merkittävän osan tästä väitöskirjasta. Havainnot osoittavat että nykyään maailmankaikkeuden laajeneminen on kiihtyvää. Kiihtyvää laajenemista on vaikea selittää maailmankaikkeudessa joka koostuu ainoastaan tavallisesta aineesta, mutta se voidaan ymmärtää mikäli maailmankaikkeudessa on energiakomponentti jolla on negatiivinen paine. Tätä kutsutaan pimeäksi energiaksi. Pimeää energiaa ei kuitenkaan ymmärretä vielä teoreettisella tasolla. Tässä keskitymme niin kutsutun integroidun Sachs-Wolfe-efektin käyttöön pimeän energian dynaamisten vaikutuksen…

Subjects/Keywords: cosmology; cosmology

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APA (6^th Edition):

Flender, S. (2014). Formation of Large-Scale Structure and its Imprint on the Cosmic Microwave Background. (Doctoral Dissertation). University of Helsinki. Retrieved from http://hdl.handle.net/10138/42877

Chicago Manual of Style (16^th Edition):

Flender, Samuel. “Formation of Large-Scale Structure and its Imprint on the Cosmic Microwave Background.” 2014. Doctoral Dissertation, University of Helsinki. Accessed March 04, 2021. http://hdl.handle.net/10138/42877.

MLA Handbook (7^th Edition):

Flender, Samuel. “Formation of Large-Scale Structure and its Imprint on the Cosmic Microwave Background.” 2014. Web. 04 Mar 2021.

Vancouver:

Flender S. Formation of Large-Scale Structure and its Imprint on the Cosmic Microwave Background. [Internet] [Doctoral dissertation]. University of Helsinki; 2014. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10138/42877.

Council of Science Editors:

Flender S. Formation of Large-Scale Structure and its Imprint on the Cosmic Microwave Background. [Doctoral Dissertation]. University of Helsinki; 2014. Available from: http://hdl.handle.net/10138/42877

University of Victoria

6. Chamberlain, Paul Geoffrey. The experiential significance of landscape in the Shakespearean imagination.

Degree: Department of Geography, 2018, University of Victoria

URL: https://dspace.library.uvic.ca//handle/1828/9633

► The application of literature to geographical research has been a matter of interest to scholars since antiquity but, apart from several normative statements on this… (more)

▼ The application of literature to geographical research has been a matter of interest to scholars since antiquity but, apart from several normative statements on this subject in the past, literary geography has not been a serious focus of geographical inquiry until relatively recently. Since the early 1970s, however, humanistic geographers have been probing literature assiduously not simply for its geographical content, but for the subtle clues that it provides in helping us to better understand the mundane, contradictory and transcendental experiences of human beings in relation to their environment. It is upon the latter that this research focuses. Specifically, the purpose of this study was to explore the experiential significance of landscape in the Shakespearean imagination in the belief that by doing so we can not only shed new light on the perceptions, attitudes and values of the culture in which it was written, but also improve our own understanding of the world in which we live. Although an enormous amount of research has been undertaken on William Shakespeare, litterateurs have tended to ignore many aspects of the playwright’s work that are so important to geography. In focusing upon Shakespeare’s dramatic landscape, I have attempted to fill this gap. First, I identify a wide variety of elements of the landscape according to their frequency of occurrence; then, through the application of phenomenology and hermeneutics, I have endeavoured to disclose the meaning of these elements as they are portrayed in the text; the application of polarity, ambiguity and antinomy, as well as the literary devices of symbolism, simile and metaphor have been used to enrich the discourse. My method of inquiry is superimposed upon a conceptual framework in which I first examine the landscape from the macroscale, focusing upon the cosmic landscape of Elizabethan cosmology, terrestrial space and the stage; then I approach the landscape from the mesoscale, by exploring the regional landscape of the city, the middle landscape and the wilderness; finally, I concentrate upon specific landscape elements within the regional landscape, by classifying them into either a territorial core, interactional space or public space. The study ends by identifying some important concepts from within the research framework and I elaborate upon these in an attempt to disclose more fully the experiential significance of landscape in the Shakespearean imagination. One of the most important concepts identified in this study is the pervasive use of the body-landscape metaphor. However, the landscape:body metaphor is far more prevalent in Shakespeare's work, because the body:landscape metaphor did not become more widely adopted until much later in history. Nevertheless, Elizabethan cosmology is clearly reflected in the spatial representation of the landscape: the city is a symbol of order and a metaphor for paradise; the wilderness is a symbol of chaos and a metaphor for hell; and the middle landscape mediates between this antinomy. But… Advisors/Committee Members: Porteous, J. Douglas (supervisor).

Subjects/Keywords: Cosmology in literature; Cosmology, Medieval

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APA (6^th Edition):

Chamberlain, P. G. (2018). The experiential significance of landscape in the Shakespearean imagination. (Thesis). University of Victoria. Retrieved from https://dspace.library.uvic.ca//handle/1828/9633

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chamberlain, Paul Geoffrey. “The experiential significance of landscape in the Shakespearean imagination.” 2018. Thesis, University of Victoria. Accessed March 04, 2021. https://dspace.library.uvic.ca//handle/1828/9633.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chamberlain, Paul Geoffrey. “The experiential significance of landscape in the Shakespearean imagination.” 2018. Web. 04 Mar 2021.

Vancouver:

Chamberlain PG. The experiential significance of landscape in the Shakespearean imagination. [Internet] [Thesis]. University of Victoria; 2018. [cited 2021 Mar 04]. Available from: https://dspace.library.uvic.ca//handle/1828/9633.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chamberlain PG. The experiential significance of landscape in the Shakespearean imagination. [Thesis]. University of Victoria; 2018. Available from: https://dspace.library.uvic.ca//handle/1828/9633

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universiteit Utrecht

7. Urzainqui Aramburu, I. A new slow-roll paradigm in multifield inflation.

Degree: 2016, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/335285

► Increasing effort has been put over the past few years to understand the consequences of the presence of several scalar fields in an early inflationary… (more)

Subjects/Keywords: Cosmology; Inflation

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APA (6^th Edition):

Urzainqui Aramburu, I. (2016). A new slow-roll paradigm in multifield inflation. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/335285

Chicago Manual of Style (16^th Edition):

Urzainqui Aramburu, I. “A new slow-roll paradigm in multifield inflation.” 2016. Masters Thesis, Universiteit Utrecht. Accessed March 04, 2021. http://dspace.library.uu.nl:8080/handle/1874/335285.

MLA Handbook (7^th Edition):

Urzainqui Aramburu, I. “A new slow-roll paradigm in multifield inflation.” 2016. Web. 04 Mar 2021.

Vancouver:

Urzainqui Aramburu I. A new slow-roll paradigm in multifield inflation. [Internet] [Masters thesis]. Universiteit Utrecht; 2016. [cited 2021 Mar 04]. Available from: http://dspace.library.uu.nl:8080/handle/1874/335285.

Council of Science Editors:

Urzainqui Aramburu I. A new slow-roll paradigm in multifield inflation. [Masters Thesis]. Universiteit Utrecht; 2016. Available from: http://dspace.library.uu.nl:8080/handle/1874/335285

Cornell University

8. Byun, Joyce. Probing The Physics Of Inflation: Searching For Non-Gaussianity In The Cosmic Microwave Background And Large-Scale Structure.

Degree: PhD, Astronomy, 2015, Cornell University

URL: http://hdl.handle.net/1813/41101

► Over thirty years since an early epoch of inflation was proposed as an elegant way solution to the Big Bang's flatness, horizon, and monopole problems,… (more)

▼ Over thirty years since an early epoch of inflation was proposed as an elegant way solution to the Big Bang's flatness, horizon, and monopole problems, recent theoretical and observational advances have made it possible to robustly test the physics of inflation using a variety of cosmological probes. It is now known that the higher-order correlators of primordial fluctuations beyond the power spectrum, starting with the bispectrum (or 'shape'), is highly sensitive to the specific physical model of inflation, and this has motivated an intense effort to robustly extract bispectrum constraints from current and upcoming data sets. This thesis aims to build on existing methods for reconstructing the amplitude and wavenumber-dependence of primordial bispectra and making robust inferences about the inflationary physics of our Universe, given cosmic microwave background (CMB) data from Planck and future large-scale structure (LSS) surveys, such as DESI and Euclid. We present forecasted constraints from CMB bispectrum data for a range of inflationary shapes, ranging from fixed individual templates, which are meant to represent distinctive features of large classes of physical models, to more general shapes and joint constraints on sets of shapes, which are important for quantifying how well the data may be able to detect bispectrum signatures that are not already theoretically predicted, and how well it may distinguish be- tween competing theories. In addition, to better model general bispectra that may have complex behavior on squeezed triangle configurations of (k1 , k2 , k3 ), we created an alternative divergent basis for reconstructing bispectra. Next, we extend this analysis to a wholly different probe of inflation that will become available when large galaxy surveys come online in the next decade: the scale-dependent halo bias as measured from galaxy power spectra. Our analysis shows that the two probes of bispectra from the CMB and LSS can be quite complementary, especially if we can obtain a strong prior on the galaxy bias from external data sets. We also show that although previous analyses have focused on the large-scale halo bias, the small-scale halo bias also contains information that can be used to constrain and discriminate between models. Finally, we narrow our focus to a class of inflationary theories that have non-trivial initial quantum states for the inflaton, as these models have in the past not been well-constrained due to the limitations of current reconstruction methods. We present an alternative basis, derived from b-splines, which can reconstruct the sharp localized peaks and oscillatory features typical of bispectra in these models, and show that the b-spline basis is competitive with other choices of basis, partly because b-spline basis functions are more easily generated. Advisors/Committee Members: Bean,Rachel E. (chair), Chernoff,David Fisher (committee member), Flanagan,Eanna E (committee member), Haynes,Martha Patricia (committee member).

Subjects/Keywords: cosmology; inflation

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APA (6^th Edition):

Byun, J. (2015). Probing The Physics Of Inflation: Searching For Non-Gaussianity In The Cosmic Microwave Background And Large-Scale Structure. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/41101

Chicago Manual of Style (16^th Edition):

Byun, Joyce. “Probing The Physics Of Inflation: Searching For Non-Gaussianity In The Cosmic Microwave Background And Large-Scale Structure.” 2015. Doctoral Dissertation, Cornell University. Accessed March 04, 2021. http://hdl.handle.net/1813/41101.

MLA Handbook (7^th Edition):

Byun, Joyce. “Probing The Physics Of Inflation: Searching For Non-Gaussianity In The Cosmic Microwave Background And Large-Scale Structure.” 2015. Web. 04 Mar 2021.

Vancouver:

Byun J. Probing The Physics Of Inflation: Searching For Non-Gaussianity In The Cosmic Microwave Background And Large-Scale Structure. [Internet] [Doctoral dissertation]. Cornell University; 2015. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1813/41101.

Council of Science Editors:

Byun J. Probing The Physics Of Inflation: Searching For Non-Gaussianity In The Cosmic Microwave Background And Large-Scale Structure. [Doctoral Dissertation]. Cornell University; 2015. Available from: http://hdl.handle.net/1813/41101

Vanderbilt University

9. Watson, Douglas F. Constraining the physics of galaxy formation and evolution using galaxy clustering.

Degree: PhD, Physics, 2012, Vanderbilt University

URL: http://hdl.handle.net/1803/10784

► The last decade has transformed the ﬁeld of cosmology into a precision science. We now know to great accuracy that the matter content of the… (more)

▼ The last decade has transformed the ﬁeld of cosmology into a precision science. We now know to great accuracy that the matter content of the Universe consists of approximately 85% in the form of the mysterious dark matter and the remaining 15% in the form of ordinary, baryonic matter. Much of this baryonic matter is locked up in galaxies, and understanding the spatial distribution, or “clustering”, of galaxies as they relate to the more ubiquitous dark matter is one of the principal goals of galaxy formation theory. There is now an established concordance cosmological model known as ΛCDM. This model has successfully passed a gauntlet of tests on large scales, but studying the small scales (< 1Mpc) is non-trivial, as the physics is quite complicated. This thesis is primarily centered on studying the tumultuous lives of satellite galaxies (galaxies that orbit around a brighter galaxy) by means of the galaxy correlation function, ξ (r), a common statistic that describes the spatial clustering of galaxies. I focus on three distinct, yet connected, unsolved problems of galaxy formation elucidated by galaxy clustering. First, I confront the long-standing conundrum of the observed power-law nature of ξ (r) from a theoretical standpoint. I reveal how a nearly power-law ξ (r) requires a conspiracy between otherwise unrelated physical processes. Second, I discuss a powerful new technique that uses the spatial clustering of satellite galaxies to understand how their stellar mass loss occurs. I ﬁnd the interesting result that low-luminosity satellite galaxies experience substantially more eﬃcient stellar mass loss than luminous satellites. I am also able to successfully predict current intrahalo light (IHL) observations and thus further constrain our stellar mass loss models. Lastly, by modeling recent measurements of the very small-scale clustering of a wide range of galaxy classes, I uncover a strong luminosity trend of the radial density proﬁle of satellite galaxies, wherein bright satellites are poor tracers of the dominant underlying dark matter. This result could possibly lead to a test of the ΛCDM model at the extreme small scales. Advisors/Committee Members: Andreas Berlind (Committee Chair).

Subjects/Keywords: astrophysics; cosmology

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APA (6^th Edition):

Watson, D. F. (2012). Constraining the physics of galaxy formation and evolution using galaxy clustering. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10784

Chicago Manual of Style (16^th Edition):

Watson, Douglas F. “Constraining the physics of galaxy formation and evolution using galaxy clustering.” 2012. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/10784.

MLA Handbook (7^th Edition):

Watson, Douglas F. “Constraining the physics of galaxy formation and evolution using galaxy clustering.” 2012. Web. 04 Mar 2021.

Vancouver:

Watson DF. Constraining the physics of galaxy formation and evolution using galaxy clustering. [Internet] [Doctoral dissertation]. Vanderbilt University; 2012. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/10784.

Council of Science Editors:

Watson DF. Constraining the physics of galaxy formation and evolution using galaxy clustering. [Doctoral Dissertation]. Vanderbilt University; 2012. Available from: http://hdl.handle.net/1803/10784

University of Oxford

10. Kodwani, Darsh. Origin & evolution of the universe.

Degree: PhD, 2020, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:d3866c43-7173-4288-967c-2c2c612cce5d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808387

► The aim of this thesis is to question some of the basic assumptions that go into building the ΛCDM model of our universe. The assumptions… (more)

▼ The aim of this thesis is to question some of the basic assumptions that go into building the ΛCDM model of our universe. The assumptions we focus on are the initial conditions of the universe, the fundamental forces in the universe on large scales and the approximations made in analysing cosmological data. For each of the assumptions we outline the theoretical understanding behind them, the current methods used to study them and how they can be improved and finally we also perform numerical analysis to quantify the novel solutions/methods we propose to extend the previous assumptions. The work on the initial conditions of the universe focuses on understanding what the most general, gauge invariant, perturbations are present in the beginning of the universe and how they impact observables such as the CMB anisotropies. We show that the most general set of initial conditions allows for a decaying adiabatic solution which can have a non-zero contribution to the perturbations in the early universe. The decaying mode sourced during an inflationary phase would be highly suppressed and should have no observational effect, thus, if these modes are detected they could potentially rule out most models of inflation and would require a new framework to understand the early universe such as a bouncing/cyclic universe. After studying the initial conditions of the universe, we focus on understanding the nature of gravity on the largest scales. It is assumed that gravity is the only force that acts on large scales in the universe and we propose a novel test of this by cross-correlating two different types of galaxies that should be sensitive to fifth-force's in the universe. By focusing on a general class of scalar-tensor theories that have a property of screening, where the effect of the fifth force depends on the local energy density, we show that future surveys will have the power to constrain screened fifth-forces using the method we propose. Finally, to test theoretical models with observations a complete understanding of the statistical methods used to compare data with theory is required. The goal of a statistical analysis in cosmology is usually to infer cosmological parameters that describe our theoretical model from observational data. We focus on one particular aspect of cosmological parameter estimation which is the covariance matrix used during an inference procedure. The usual assumption in modelling the covariance matrix is that it can be computed at a fiducial point in parameter space, however, this is not self-consistent. We check this claim explicitly by calculating the effect of including the parameter dependence in the covariance matrix on the constraining power of cosmological parameters.

Subjects/Keywords: Cosmology; Gravity

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APA (6^th Edition):

Kodwani, D. (2020). Origin & evolution of the universe. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:d3866c43-7173-4288-967c-2c2c612cce5d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808387

Chicago Manual of Style (16^th Edition):

Kodwani, Darsh. “Origin & evolution of the universe.” 2020. Doctoral Dissertation, University of Oxford. Accessed March 04, 2021. http://ora.ox.ac.uk/objects/uuid:d3866c43-7173-4288-967c-2c2c612cce5d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808387.

MLA Handbook (7^th Edition):

Kodwani, Darsh. “Origin & evolution of the universe.” 2020. Web. 04 Mar 2021.

Vancouver:

Kodwani D. Origin & evolution of the universe. [Internet] [Doctoral dissertation]. University of Oxford; 2020. [cited 2021 Mar 04]. Available from: http://ora.ox.ac.uk/objects/uuid:d3866c43-7173-4288-967c-2c2c612cce5d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808387.

Council of Science Editors:

Kodwani D. Origin & evolution of the universe. [Doctoral Dissertation]. University of Oxford; 2020. Available from: http://ora.ox.ac.uk/objects/uuid:d3866c43-7173-4288-967c-2c2c612cce5d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808387

Addis Ababa University

11. Asnakew, Bewketu. DYNAMICS IN A MAXIMALLY SYMMETRIC UNIVERSE .

Degree: 2013, Addis Ababa University

URL: http://etd.aau.edu.et/dspace/handle/123456789/1322

► Our present understanding of the evolution of the universe relies upon the Friedmann- Robertson- Walker cosmological models. This model is so successful that it is… (more)

Subjects/Keywords: Cosmology; universe

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APA (6^th Edition):

Asnakew, B. (2013). DYNAMICS IN A MAXIMALLY SYMMETRIC UNIVERSE . (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/1322

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Asnakew, Bewketu. “DYNAMICS IN A MAXIMALLY SYMMETRIC UNIVERSE .” 2013. Thesis, Addis Ababa University. Accessed March 04, 2021. http://etd.aau.edu.et/dspace/handle/123456789/1322.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Asnakew, Bewketu. “DYNAMICS IN A MAXIMALLY SYMMETRIC UNIVERSE .” 2013. Web. 04 Mar 2021.

Vancouver:

Asnakew B. DYNAMICS IN A MAXIMALLY SYMMETRIC UNIVERSE . [Internet] [Thesis]. Addis Ababa University; 2013. [cited 2021 Mar 04]. Available from: http://etd.aau.edu.et/dspace/handle/123456789/1322.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Asnakew B. DYNAMICS IN A MAXIMALLY SYMMETRIC UNIVERSE . [Thesis]. Addis Ababa University; 2013. Available from: http://etd.aau.edu.et/dspace/handle/123456789/1322

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queen Mary, University of London

12. Durk, J. Exact, inhomogeneous solutions to gravitational theories in cosmology.

Degree: PhD, 2019, Queen Mary, University of London

URL: http://qmro.qmul.ac.uk/xmlui/handle/123456789/59270 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.786402

► Solving the backreaction and averaging problems is important as we enter the era of precision cosmology. Fundamentally, the idea that small-scale inhomogeneities can a ect… (more)

▼ Solving the backreaction and averaging problems is important as we enter the era of precision cosmology. Fundamentally, the idea that small-scale inhomogeneities can a ect the large-scale dynamics of the Universe lies in the non-linearity and non-commutativity properties of the Einstein eld equations. It is not necessarily the case that the dynamics of a perfectly homogeneous Friedmann universe are the same as an inhomogeneous one. However, di culties arise in nding suitable inhomogeneous solutions to the Einstein eld equations. Progress can be made by treating it as an initial data problem and solving the constraint equations. This gives rise to a family of solutions, the black hole lattices, which consist of linearly superposed Schwarzschild masses representing a universe with a discretised matter content. In this thesis, we present extensions and generalisations of these existing models. Firstly, we devised a novel way to include structure formation and its e ects. We did this in a quasi-static approach that involved splitting the black holes up into more masses and moving them along parameterised trajectories. For small values of this parameter, we could induce clustering as the black holes were su ciently close together. We found an extra apparent horizon encompassed the cluster and that in order to reduce backreaction, interaction energies within clustered masses needed to be included. Our next two extensions involved adding in extra elds, either electric charge or the cosmological constant. Finally we considered the lattices in an alternative scalar-tensor gravitational theory, Brans-Dicke. We found our lattices reduced to their relativistic versions in the appropriate limit, but for some values very far from general relativity, we could reduce backreaction to zero by altering the amount of background scalar eld. For all of our analyses we found that increasing the number of masses reduces the discrepancy between our lattice cosmologies and continuous counterparts.

Subjects/Keywords: inhomogeneities; Cosmology

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APA (6^th Edition):

Durk, J. (2019). Exact, inhomogeneous solutions to gravitational theories in cosmology. (Doctoral Dissertation). Queen Mary, University of London. Retrieved from http://qmro.qmul.ac.uk/xmlui/handle/123456789/59270 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.786402

Chicago Manual of Style (16^th Edition):

Durk, J. “Exact, inhomogeneous solutions to gravitational theories in cosmology.” 2019. Doctoral Dissertation, Queen Mary, University of London. Accessed March 04, 2021. http://qmro.qmul.ac.uk/xmlui/handle/123456789/59270 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.786402.

MLA Handbook (7^th Edition):

Durk, J. “Exact, inhomogeneous solutions to gravitational theories in cosmology.” 2019. Web. 04 Mar 2021.

Vancouver:

Durk J. Exact, inhomogeneous solutions to gravitational theories in cosmology. [Internet] [Doctoral dissertation]. Queen Mary, University of London; 2019. [cited 2021 Mar 04]. Available from: http://qmro.qmul.ac.uk/xmlui/handle/123456789/59270 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.786402.

Council of Science Editors:

Durk J. Exact, inhomogeneous solutions to gravitational theories in cosmology. [Doctoral Dissertation]. Queen Mary, University of London; 2019. Available from: http://qmro.qmul.ac.uk/xmlui/handle/123456789/59270 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.786402

Universidad de Cantabria

13. López-Caniego Alcarria, Marcos. Detection of point sources in maps of the cosmic microwave background radiation by means of optimal filters.

Degree: 2007, Universidad de Cantabria

URL: http://hdl.handle.net/10902/1582

► RESUMEN: Cuando observamos el cielo con los instrumentos más avanzados en la frecuencia de las microondas, los fotones que vemos fueron originados en regiones muy… (more)

▼ RESUMEN: Cuando observamos el cielo con los instrumentos más avanzados en la frecuencia de las microondas, los fotones que vemos fueron originados en regiones muy diferentes del universo. La mayoría proceden de nuestra propia galaxia (emisión difusa de sincrotrón, free-free y polvo), otros se originan en galaxias y cúmulos de galaxias muy lejanos, y, finalmente, una fracción tendrá su origen en la radiación del Big Bang, conocida como la Radiación del Fondo Cósmico de Microondas. Esta radiación está contaminada por las otras y su separación de ellas de una forma satisfactoria sigue siendo un problema abierto. En esta tesis exploraremos diferentes técnicas basadas en filtros lineales para detectar y separar uno de estos contaminantes, la contribución a la señal que se observa de radio galaxias y galaxias infrarrojas lejanas. Éstas son conocidas como fuentes puntuales porque aparecen como objetos puntuales no resueltos -debido a las típicas resoluciones angulares de los instrumentos usados en los experimentos-. En primer lugar, vamos a estudiar las propiedades de una familia de filtros adaptados para la detección de fuentes puntuales, donde modificamos la escala del filtro y usamos un test de Neyman-Pearson para definir la región de aceptación. En segundo lugar, consideramos un nuevo filtro (BSAF) que tiene dos parámetros que se pueden optimizar para maximizar el número de detecciones reales fijado un número de detecciones espurias. En tercer lugar, extendemos el BSAF al caso dos-dimensional y lo comparamos con la ondícula de sombrero mejicano (MHW). En cuarto lugar, estudiamos una nueva técnica de fusión de lineal y cuadrática de imágenes. En quinto lugar, comparamos tres filtros usando simulaciones realistas de Planck. En sexto lugar, para terminar, usamos el segundo miembro de la familia de ondículas de sombrero mejicano para hacer una detección no-ciega en las cinco frecuencias del satélite WMAP, analizando 2491 objetos observados a 5 GHz y produciendo un catálogo de 932 objetos observados a 3σ y 380 a 5σ. Advisors/Committee Members: Sanz Estévez, José Luis (advisor), Universidad de Cantabria (other).

Subjects/Keywords: Cosmology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

López-Caniego Alcarria, M. (2007). Detection of point sources in maps of the cosmic microwave background radiation by means of optimal filters. (Doctoral Dissertation). Universidad de Cantabria. Retrieved from http://hdl.handle.net/10902/1582

Chicago Manual of Style (16^th Edition):

López-Caniego Alcarria, Marcos. “Detection of point sources in maps of the cosmic microwave background radiation by means of optimal filters.” 2007. Doctoral Dissertation, Universidad de Cantabria. Accessed March 04, 2021. http://hdl.handle.net/10902/1582.

MLA Handbook (7^th Edition):

López-Caniego Alcarria, Marcos. “Detection of point sources in maps of the cosmic microwave background radiation by means of optimal filters.” 2007. Web. 04 Mar 2021.

Vancouver:

López-Caniego Alcarria M. Detection of point sources in maps of the cosmic microwave background radiation by means of optimal filters. [Internet] [Doctoral dissertation]. Universidad de Cantabria; 2007. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10902/1582.

Council of Science Editors:

López-Caniego Alcarria M. Detection of point sources in maps of the cosmic microwave background radiation by means of optimal filters. [Doctoral Dissertation]. Universidad de Cantabria; 2007. Available from: http://hdl.handle.net/10902/1582

Princeton University

14. Parker, Lucas. The Atacama B-Mode Search: Instrumentation and Observations .

Degree: PhD, 2015, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp01b5644t92v

► The Atacama B-Mode Search (ABS) is an experiment designed to probe the physics of the early universe by searching for the signature of gravitational waves… (more)

Subjects/Keywords: CMB; Cosmology

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APA (6^th Edition):

Parker, L. (2015). The Atacama B-Mode Search: Instrumentation and Observations . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01b5644t92v

Chicago Manual of Style (16^th Edition):

Parker, Lucas. “The Atacama B-Mode Search: Instrumentation and Observations .” 2015. Doctoral Dissertation, Princeton University. Accessed March 04, 2021. http://arks.princeton.edu/ark:/88435/dsp01b5644t92v.

MLA Handbook (7^th Edition):

Parker, Lucas. “The Atacama B-Mode Search: Instrumentation and Observations .” 2015. Web. 04 Mar 2021.

Vancouver:

Parker L. The Atacama B-Mode Search: Instrumentation and Observations . [Internet] [Doctoral dissertation]. Princeton University; 2015. [cited 2021 Mar 04]. Available from: http://arks.princeton.edu/ark:/88435/dsp01b5644t92v.

Council of Science Editors:

Parker L. The Atacama B-Mode Search: Instrumentation and Observations . [Doctoral Dissertation]. Princeton University; 2015. Available from: http://arks.princeton.edu/ark:/88435/dsp01b5644t92v

University of Cape Town

15. Fantaye, Yabebal. Probing primordial non-Gaussianity using large scale structure.

Degree: Image, Astronomy, 2009, University of Cape Town

URL: http://hdl.handle.net/11427/6101

► Recent evidence from the WMAP satellite has lead to a tentative detection of non-Gaussianity. Using the bispectrum statistic applied to the MegaZ catalogue of over… (more)

Subjects/Keywords: Cosmology

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APA (6^th Edition):

Fantaye, Y. (2009). Probing primordial non-Gaussianity using large scale structure. (Thesis). University of Cape Town. Retrieved from http://hdl.handle.net/11427/6101

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fantaye, Yabebal. “Probing primordial non-Gaussianity using large scale structure.” 2009. Thesis, University of Cape Town. Accessed March 04, 2021. http://hdl.handle.net/11427/6101.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fantaye, Yabebal. “Probing primordial non-Gaussianity using large scale structure.” 2009. Web. 04 Mar 2021.

Vancouver:

Fantaye Y. Probing primordial non-Gaussianity using large scale structure. [Internet] [Thesis]. University of Cape Town; 2009. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11427/6101.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fantaye Y. Probing primordial non-Gaussianity using large scale structure. [Thesis]. University of Cape Town; 2009. Available from: http://hdl.handle.net/11427/6101

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Cape Town

16. Burger, Daniel. The KLT relations in unimodular gravity.

Degree: Image, Mathematics and Applied Mathematics, 2016, University of Cape Town

URL: http://hdl.handle.net/11427/20989

► Here we initiate a systematic study of some of the symmetry properties of unimodular gravity, building on much of the known structure of general relativity,… (more)

Subjects/Keywords: Astronomy; Cosmology

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APA (6^th Edition):

Burger, D. (2016). The KLT relations in unimodular gravity. (Thesis). University of Cape Town. Retrieved from http://hdl.handle.net/11427/20989

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Burger, Daniel. “The KLT relations in unimodular gravity.” 2016. Thesis, University of Cape Town. Accessed March 04, 2021. http://hdl.handle.net/11427/20989.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Burger, Daniel. “The KLT relations in unimodular gravity.” 2016. Web. 04 Mar 2021.

Vancouver:

Burger D. The KLT relations in unimodular gravity. [Internet] [Thesis]. University of Cape Town; 2016. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11427/20989.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Burger D. The KLT relations in unimodular gravity. [Thesis]. University of Cape Town; 2016. Available from: http://hdl.handle.net/11427/20989

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Cape Town

17. February, Sean Phillip. Rendering dark energy void.

Degree: Image, Astronomy, 2009, University of Cape Town

URL: http://hdl.handle.net/11427/11912

► The current model of cosmology, the Friedman-Lemaitre-Robertson-Valker model, assumes that the universe is approximately homogeneous and isotropic on very large scales. Further assuming flatness and… (more)

Subjects/Keywords: Cosmology

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APA (6^th Edition):

February, S. P. (2009). Rendering dark energy void. (Thesis). University of Cape Town. Retrieved from http://hdl.handle.net/11427/11912

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

February, Sean Phillip. “Rendering dark energy void.” 2009. Thesis, University of Cape Town. Accessed March 04, 2021. http://hdl.handle.net/11427/11912.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

February, Sean Phillip. “Rendering dark energy void.” 2009. Web. 04 Mar 2021.

Vancouver:

February SP. Rendering dark energy void. [Internet] [Thesis]. University of Cape Town; 2009. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11427/11912.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

February SP. Rendering dark energy void. [Thesis]. University of Cape Town; 2009. Available from: http://hdl.handle.net/11427/11912

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

18. Dimakis, Nikolaos. Η εφαρμογή Lie – point συμμετριών στην κλασσική και κβαντική κοσμολογία.

Degree: 2014, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)

URL: http://hdl.handle.net/10442/hedi/34884

►

In this paper we attempt to demonstrate the importance of symmetries both at the classical and quantum level. The originality of this work rests in… (more)

▼

In this paper we attempt to demonstrate the importance of symmetries both at the classical and quantum level. The originality of this work rests in the generalization of the theory of symmetries (of the action and the equations of motion) in systems with constraints. All theories that exhibit a gauge freedom, result from actions characterized by singular Lagrangians. The corresponding freedom for General Relativity (GR) is the invariance of the theory under random (but sufficiently smooth) diffeomorphisms. This means that four out of ten of Einstein's equations are constriants for the system. The various cosmological models that can be described by equivalent mechanical systems carry a subset of this freedom, as applications of GR. This led us to search for a method in order to extend the theory from regular systems to singular. In both of them these symmetries are conserved quantities, with the difference that for singular systems this may hold due to the constraints. After the classical treatment where we export these integrals of motion, the next step is to consider them as quantum measurable quantities. By following Dirac's line of thinking we construct the corresponding Hermitian operators defining the eigen-equations of the wave-function. Of course the number of operands that can be used in a representation in this way is bound by the dimension of the configuration space and the requirement of finding a non-trivial solution for the wavefunction. The latter leads to an integrability condition, whose satisfaction determines the operator algebra of the measured physical quantities. In an effort to extend the theory of quantization of individual geometries to broader geometrical classes, we are led to study a system whose wave-function is used to define a generalized probability. The latter is proven to exhibit its probable for extrema over the classical trajectories of the initial cosmological model under consideration. Some examples of quantizing individual geometries and geometrical classes are given.

Με αυτή την εργασία επιχειρούμε να καταδείξουμε τη δεσπόζουσα σημασία των συμμετριών τόσο σε κλασσικό όσο και σε κβαντικό επίπεδο. Η πρωτοτυπία της παρούσας εργασίας έγκειται στην επέκταση της θεωρίας για αναζήτηση συμμετριών (της δράσης αλλά και των εξισώσεων κίνησης) σε συστήματα που παρουσιάζουν δεσμούς. Όλες οι θεωρίες που παρουσιάζουν κάποιου είδους ελευθερία βαθμίδας, προκύπτουν από δράσεις που χαρακτηρίζονται από ιδιάζουσες Λαγκρανζιανές. Η αντίστοιχη ελευθερία για τη Γενική Σχετικότητα είναι η αναλλοιώτητα της θεωρίας κάτω από τυχαίες (αλλά επαρκώς ομαλές) αμφιδιαφορίσεις. Αυτό έχει ως συνέπεια τέσσερις εκ των δέκα εξισώσεων του Einsteinv να αποτελούν δεσμούς για το σύστημα. Τα διάφορα κοσμολογικά πρότυπα που μπορούν να προκύψουν ως μηχανικά συστήματα από μια απομείωση των βαθμών ελευθερίας, όντας εφαρμογές της ΓΣ, μεταφέρουν ένα υποσύνολο αυτής της ελευθερίας. Αυτό μας οδήγησε στην αναζήτηση μιας μεθόδου ώστε να επεκταθεί η θεωρία ανεύρεσης συμμετριών από τα ομαλά συστήματα στα ιδιάζοντα. Όπως στα…

Subjects/Keywords: Κοσμολογία; Cosmology

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APA (6^th Edition):

Dimakis, N. (2014). Η εφαρμογή Lie – point συμμετριών στην κλασσική και κβαντική κοσμολογία. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/34884

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Dimakis, Nikolaos. “Η εφαρμογή Lie – point συμμετριών στην κλασσική και κβαντική κοσμολογία.” 2014. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed March 04, 2021. http://hdl.handle.net/10442/hedi/34884.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Dimakis, Nikolaos. “Η εφαρμογή Lie – point συμμετριών στην κλασσική και κβαντική κοσμολογία.” 2014. Web. 04 Mar 2021.

Vancouver:

Dimakis N. Η εφαρμογή Lie – point συμμετριών στην κλασσική και κβαντική κοσμολογία. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2014. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10442/hedi/34884.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Dimakis N. Η εφαρμογή Lie – point συμμετριών στην κλασσική και κβαντική κοσμολογία. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2014. Available from: http://hdl.handle.net/10442/hedi/34884

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of British Columbia

19. Shen, Po-Yu. New cosmological model.

Degree: MS- MSc, Physics, 1970, University of British Columbia

URL: http://hdl.handle.net/2429/34930

► The present situation in cosmology is discussed. We try to explain the observed distribution of quasars in terms of an inhomogeneous model universe that consists… (more)

Subjects/Keywords: Cosmology

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APA (6^th Edition):

Shen, P. (1970). New cosmological model. (Masters Thesis). University of British Columbia. Retrieved from http://hdl.handle.net/2429/34930

Chicago Manual of Style (16^th Edition):

Shen, Po-Yu. “New cosmological model.” 1970. Masters Thesis, University of British Columbia. Accessed March 04, 2021. http://hdl.handle.net/2429/34930.

MLA Handbook (7^th Edition):

Shen, Po-Yu. “New cosmological model.” 1970. Web. 04 Mar 2021.

Vancouver:

Shen P. New cosmological model. [Internet] [Masters thesis]. University of British Columbia; 1970. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/2429/34930.

Council of Science Editors:

Shen P. New cosmological model. [Masters Thesis]. University of British Columbia; 1970. Available from: http://hdl.handle.net/2429/34930

The Ohio State University

20. Zentner, Andrew Ronald. Probing the new cosmology.

Degree: PhD, Physics, 2003, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1054160085

► Improvements in obserational techniques have transformed cosmology into a field inundated with ever-expanding, high-quality data sets and driven cosmology toward a standard model where the… (more)

▼ Improvements in obserational techniques have transformed cosmology into a field inundated with ever-expanding, high-quality data sets and driven cosmology toward a standard model where the classic cosmological parameters are accurately measured. I briefly discuss some of the methods used to determine cosmological parameters, particularly primordial nucleosynthesis, the magnitude-redshift relation of supernovae, and cosmic microwave background anisotropy. I demonstrate how cosmological data can be used to complement particle physics and constrain extensions to the Standard Model. Specifically, I present bounds on light particle species and the properties of unstable, weakly-interacting, massive particles. Despite the myriad successes of the emerging cosmological model, unanswered questions linger. Numerical simulations of structure formation predict galactic central densities that are considerably higher than observed. They also reveal hundreds of satellites orbiting Milky Way-like galaxies while the Milky Way has only eleven known satellites within 300kpc. I explore the possibility that these conundrums may have a common remedy in the form of the power spectrum of initial density fluctuations that seed structure growth. To address the substructure issue, I develop a semi-analytic method that suffers from no inherent resolution limits and can therefore be used to complement numerical simulations. I find that tilted primordial power spectra and spectra with running tilts provide for an intriguing possibility. In these models, the amplitude of initial fluctuations can be normalized against the cosmic microwave background measurements on large scales. Yet, the reduction in small-scale power brings galactic central densities down to acceptable levels and allows for the Milky Way satellite population to be accounted for without invoking differential feedback mechanisms. Furthermore, substructure mass fractions are not significantly altered in these models so probes of substructure via gravitational lensing do not disfavor them. The primordial fluctuations are thought to be generated during an early epoch of inflation and one implication is that galaxy properties may convey information about inflation. I also address alternative proposals, such as warm dark matter and broken scale-invariant inflation, in light of lensing probes of substructure and find these models to be disfavored. I close with a few words on refining the model and alternative applications. Advisors/Committee Members: Walker, Terrence (Advisor).

Subjects/Keywords: Cosmology

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APA (6^th Edition):

Zentner, A. R. (2003). Probing the new cosmology. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1054160085

Chicago Manual of Style (16^th Edition):

Zentner, Andrew Ronald. “Probing the new cosmology.” 2003. Doctoral Dissertation, The Ohio State University. Accessed March 04, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1054160085.

MLA Handbook (7^th Edition):

Zentner, Andrew Ronald. “Probing the new cosmology.” 2003. Web. 04 Mar 2021.

Vancouver:

Zentner AR. Probing the new cosmology. [Internet] [Doctoral dissertation]. The Ohio State University; 2003. [cited 2021 Mar 04]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1054160085.

Council of Science Editors:

Zentner AR. Probing the new cosmology. [Doctoral Dissertation]. The Ohio State University; 2003. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1054160085

University of Oxford

21. Robertson, Naomi Clare. Observing the dark universe with weak gravitational lensing.

Degree: PhD, 2019, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:4e51fcdf-d7d3-483f-9925-c0837da455db ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.820805

► We are now entering into an era of huge cosmological data sets, with observations testing the current paradigm to high accuracy. By combining different probes… (more)

Subjects/Keywords: observational cosmology

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APA (6^th Edition):

Robertson, N. C. (2019). Observing the dark universe with weak gravitational lensing. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:4e51fcdf-d7d3-483f-9925-c0837da455db ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.820805

Chicago Manual of Style (16^th Edition):

Robertson, Naomi Clare. “Observing the dark universe with weak gravitational lensing.” 2019. Doctoral Dissertation, University of Oxford. Accessed March 04, 2021. http://ora.ox.ac.uk/objects/uuid:4e51fcdf-d7d3-483f-9925-c0837da455db ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.820805.

MLA Handbook (7^th Edition):

Robertson, Naomi Clare. “Observing the dark universe with weak gravitational lensing.” 2019. Web. 04 Mar 2021.

Vancouver:

Robertson NC. Observing the dark universe with weak gravitational lensing. [Internet] [Doctoral dissertation]. University of Oxford; 2019. [cited 2021 Mar 04]. Available from: http://ora.ox.ac.uk/objects/uuid:4e51fcdf-d7d3-483f-9925-c0837da455db ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.820805.

Council of Science Editors:

Robertson NC. Observing the dark universe with weak gravitational lensing. [Doctoral Dissertation]. University of Oxford; 2019. Available from: http://ora.ox.ac.uk/objects/uuid:4e51fcdf-d7d3-483f-9925-c0837da455db ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.820805

University of Canterbury

22. McKay, James Hadden. The cosmological rest frame.

Degree: MS, Physics, 2015, University of Canterbury

URL: http://dx.doi.org/10.26021/6882

► The analysis of the uniformity of a spherically averaged Hubble expansion in the Local Group frame of reference by Wiltshire, Smale, Mattsson and Watkins (2013)… (more)

Subjects/Keywords: cosmology - observations; cosmology - theory; distance scale

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APA (6^th Edition):

McKay, J. H. (2015). The cosmological rest frame. (Masters Thesis). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/6882

Chicago Manual of Style (16^th Edition):

McKay, James Hadden. “The cosmological rest frame.” 2015. Masters Thesis, University of Canterbury. Accessed March 04, 2021. http://dx.doi.org/10.26021/6882.

MLA Handbook (7^th Edition):

McKay, James Hadden. “The cosmological rest frame.” 2015. Web. 04 Mar 2021.

Vancouver:

McKay JH. The cosmological rest frame. [Internet] [Masters thesis]. University of Canterbury; 2015. [cited 2021 Mar 04]. Available from: http://dx.doi.org/10.26021/6882.

Council of Science Editors:

McKay JH. The cosmological rest frame. [Masters Thesis]. University of Canterbury; 2015. Available from: http://dx.doi.org/10.26021/6882

University of Canterbury

23. Smale, Peter Rich. Observations and inhomogeneity in cosmology.

Degree: PhD, Astronomy, 2012, University of Canterbury

URL: http://dx.doi.org/10.26021/5947

► We interpret distance measurements from nearby galaxies, type Ia supernovae, and gamma-ray bursts in the light of a cosmological model that incorporates a spatial averaging… (more)

Subjects/Keywords: cosmology; timescape model; observational cosmology; inhomogeneity

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APA (6^th Edition):

Smale, P. R. (2012). Observations and inhomogeneity in cosmology. (Doctoral Dissertation). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/5947

Chicago Manual of Style (16^th Edition):

Smale, Peter Rich. “Observations and inhomogeneity in cosmology.” 2012. Doctoral Dissertation, University of Canterbury. Accessed March 04, 2021. http://dx.doi.org/10.26021/5947.

MLA Handbook (7^th Edition):

Smale, Peter Rich. “Observations and inhomogeneity in cosmology.” 2012. Web. 04 Mar 2021.

Vancouver:

Smale PR. Observations and inhomogeneity in cosmology. [Internet] [Doctoral dissertation]. University of Canterbury; 2012. [cited 2021 Mar 04]. Available from: http://dx.doi.org/10.26021/5947.

Council of Science Editors:

Smale PR. Observations and inhomogeneity in cosmology. [Doctoral Dissertation]. University of Canterbury; 2012. Available from: http://dx.doi.org/10.26021/5947

University of Oxford

24. Lorenz, Christiane Stefanie. Neutrino cosmology and large scale structure.

Degree: PhD, 2020, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:3a055121-2a10-4c01-aa34-e789459df6de ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808286

► The topic of this thesis is neutrino cosmology and large scale structure. First, we introduce the concepts needed for the presentation in the following chapters.… (more)

Subjects/Keywords: Neutrino physics; Cosmology

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APA (6^th Edition):

Lorenz, C. S. (2020). Neutrino cosmology and large scale structure. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:3a055121-2a10-4c01-aa34-e789459df6de ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808286

Chicago Manual of Style (16^th Edition):

Lorenz, Christiane Stefanie. “Neutrino cosmology and large scale structure.” 2020. Doctoral Dissertation, University of Oxford. Accessed March 04, 2021. http://ora.ox.ac.uk/objects/uuid:3a055121-2a10-4c01-aa34-e789459df6de ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808286.

MLA Handbook (7^th Edition):

Lorenz, Christiane Stefanie. “Neutrino cosmology and large scale structure.” 2020. Web. 04 Mar 2021.

Vancouver:

Lorenz CS. Neutrino cosmology and large scale structure. [Internet] [Doctoral dissertation]. University of Oxford; 2020. [cited 2021 Mar 04]. Available from: http://ora.ox.ac.uk/objects/uuid:3a055121-2a10-4c01-aa34-e789459df6de ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808286.

Council of Science Editors:

Lorenz CS. Neutrino cosmology and large scale structure. [Doctoral Dissertation]. University of Oxford; 2020. Available from: http://ora.ox.ac.uk/objects/uuid:3a055121-2a10-4c01-aa34-e789459df6de ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808286

25. Singh, Amritbir. Investigations on certain cosmological models of general theory of relativity for existence of dark matter in the universe due to variable constants; -.

Degree: Mathematics, 2006, Punjab Technical University

URL: http://shodhganga.inflibnet.ac.in/handle/10603/8811

►

The main objective of the thesis is to construct and analyse some suitable cosmological models along with numerous cosmological consequences with Dark Matter in the… (more)

▼

The main objective of the thesis is to construct and analyse some suitable cosmological models along with numerous cosmological consequences with Dark Matter in the universe on the basis of the field equations governing the gravity as proposed by Berman and Rahman et al. recently. This thesis is divided in ten chapters. In Chapter-1, Theory of Cosmology has been discussed along with cosmology time line, Mathematical discovery of the universe, theory of variable G and variable and#923; with observational constraints. In the last section world-metric and linkage between evolutions scenario of cosmological model and space curvature is given. In 1915, Einstein proposed his General theory of Relativity (GTR) governing the gravity. He applied this theory to study the universe as a whole. For this he determined the space time metric which represents the universe as a whole. This model of universe is well known as Einstein s static model. For the construction of static model of the universe, the original form of the field equation of GTR is not suitable and therefore, Einstein introduced the cosmological term ij g L into his field equation calling it as Biggest blunder of my life . After the Hubble s experiments, a number of cosmological models have been constructed by many cosmologists with and without the cosmological term ij g L by taking positive sign of the cosmological constant (C.C.) or even its non-zero numerical value in general. In the same time those cases where the constant is nonzero, have mathematical interest more rather than the physical meaning. The spontaneous symmetry breaking results in a change in the temperature of the medium. This implies a dependence of the cosmological constant on time as may be seen in many cosmological models (discussed in detail in the thesis). In 1961, Brans and Dicke proposed the possibility of the existence of a long-range scalar field on the basis of the Mach s principle. This lead to propose that the constant of Gravitation G is not a constant

Bibliography p.124-139

Advisors/Committee Members: Mishra, R K, Dhaliwal, Sukhjit Singh.

Subjects/Keywords: Cosmology; Universe; Mathematics

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APA (6^th Edition):

Singh, A. (2006). Investigations on certain cosmological models of general theory of relativity for existence of dark matter in the universe due to variable constants; -. (Thesis). Punjab Technical University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/8811

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Singh, Amritbir. “Investigations on certain cosmological models of general theory of relativity for existence of dark matter in the universe due to variable constants; -.” 2006. Thesis, Punjab Technical University. Accessed March 04, 2021. http://shodhganga.inflibnet.ac.in/handle/10603/8811.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Singh, Amritbir. “Investigations on certain cosmological models of general theory of relativity for existence of dark matter in the universe due to variable constants; -.” 2006. Web. 04 Mar 2021.

Vancouver:

Singh A. Investigations on certain cosmological models of general theory of relativity for existence of dark matter in the universe due to variable constants; -. [Internet] [Thesis]. Punjab Technical University; 2006. [cited 2021 Mar 04]. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/8811.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Singh A. Investigations on certain cosmological models of general theory of relativity for existence of dark matter in the universe due to variable constants; -. [Thesis]. Punjab Technical University; 2006. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/8811

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Cape Town

26. Elmardi, Maye Y A. Topics in relativistic cosmology: Cosmology on the past lightcone and in modified gravitation.

Degree: Image, Mathematics and Applied Mathematics, 2018, University of Cape Town

URL: http://hdl.handle.net/11427/27877

► The lightcone gauge is a set of what are called the observational coordinates adapted to our past lightcone. We develop this gauge by producing a… (more)

▼ The lightcone gauge is a set of what are called the observational coordinates adapted to our past lightcone. We develop this gauge by producing a perturbed spacetime metric that describes the geometry of our past lightcone where observations are usually obtained. We then connect the produced observational metric to the perturbed Friedmann-Lemaître-Robertson-Walker metric in the standard general gauge or what is the so-called 1+3 gauge. We derive the relations between these perturbations of spacetime in the observational coordinates and those perturbations in the standard metric approach, as well as the dynamical equations for the perturbations in observational coordinates. We also calculate the observables in the lightcone gauge and rederive them in terms of Bardeen potentials to first order. A verification is made of the observables in the perturbed lightcone gauge with those in the standard gauge. The advantage of the method developed is that the observable relations are simpler than in the standard formalism. We use the perturbed lightcone gauge in galaxy surveys and galaxy number density contrast. The significance of the new gauge is that by considering the null-like light propagations, the calculations are much simpler since angular deviations are not considered. Standard cosmology based on General Relativity is generally believed to have serious shortcomings, such as the unexplained issues of dark matter and dark energy. As a remedy, many alternative theories of gravitation have been proposed over the years, one of which is ƒ(R) gravity. We explore classes of irrotational-fluid cosmological models in the context of ƒ(R) gravity in an attempt to put some theoretical and mathematical restrictions on the form of the ƒ(R) gravitational Lagrangian. In particular, we investigate the consistency of the linearised dust models for shear-free cases as well as in the limiting cases when either the gravito-magnetic or gravito-electric components of the Weyl tensor vanish. We also discuss the existence and consistency of classes of non-expanding irrotational spacetimes in ƒ(R)-gravity. Furthermore, we explore exact ƒ(R) gravity solutions that mimic Chaplygin-gas inspired ΛCDM cosmology. Starting with the original, generalized and modified Chaplygin gas equations of state, we reconstruct the forms of ƒ(R) Lagrangians. The resulting solutions are generally quadratic in the Ricci scalar, but have appropriate ΛCDM solutions in limiting cases. These solutions, given appropriate initial conditions, can be potential candidates for scalar field-driven early universe expansion (in ation) and dark energy-driven late-time cosmic acceleration. Advisors/Committee Members: Clarkson, Chris (advisor), Larena, Julien (advisor).

Subjects/Keywords: Applied Mathematics; Cosmology

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APA (6^th Edition):

Elmardi, M. Y. A. (2018). Topics in relativistic cosmology: Cosmology on the past lightcone and in modified gravitation. (Thesis). University of Cape Town. Retrieved from http://hdl.handle.net/11427/27877

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Elmardi, Maye Y A. “Topics in relativistic cosmology: Cosmology on the past lightcone and in modified gravitation.” 2018. Thesis, University of Cape Town. Accessed March 04, 2021. http://hdl.handle.net/11427/27877.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Elmardi, Maye Y A. “Topics in relativistic cosmology: Cosmology on the past lightcone and in modified gravitation.” 2018. Web. 04 Mar 2021.

Vancouver:

Elmardi MYA. Topics in relativistic cosmology: Cosmology on the past lightcone and in modified gravitation. [Internet] [Thesis]. University of Cape Town; 2018. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/11427/27877.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Elmardi MYA. Topics in relativistic cosmology: Cosmology on the past lightcone and in modified gravitation. [Thesis]. University of Cape Town; 2018. Available from: http://hdl.handle.net/11427/27877

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Cambridge

27. Shimwell, Timothy William. Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager.

Degree: PhD, 2011, University of Cambridge

URL: http://www.dspace.cam.ac.uk/handle/1810/241039https://www.repository.cam.ac.uk/bitstream/1810/241039/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/5/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/6/thesis.pdf.jpg

► In this thesis I discuss my work on the Arcminute Microkelvin Imager (AMI). I focus on the detection of Sunyaev-Zel’dovich (SZ) signatures at 14-18GHz. Once… (more)

Subjects/Keywords: Observationjal cosmology; Interferometry

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APA (6^th Edition):

Shimwell, T. W. (2011). Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager. (Doctoral Dissertation). University of Cambridge. Retrieved from http://www.dspace.cam.ac.uk/handle/1810/241039https://www.repository.cam.ac.uk/bitstream/1810/241039/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/5/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/6/thesis.pdf.jpg

Chicago Manual of Style (16^th Edition):

Shimwell, Timothy William. “Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager.” 2011. Doctoral Dissertation, University of Cambridge. Accessed March 04, 2021. http://www.dspace.cam.ac.uk/handle/1810/241039https://www.repository.cam.ac.uk/bitstream/1810/241039/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/5/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/6/thesis.pdf.jpg.

MLA Handbook (7^th Edition):

Shimwell, Timothy William. “Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager.” 2011. Web. 04 Mar 2021.

Vancouver:

Shimwell TW. Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager. [Internet] [Doctoral dissertation]. University of Cambridge; 2011. [cited 2021 Mar 04]. Available from: http://www.dspace.cam.ac.uk/handle/1810/241039https://www.repository.cam.ac.uk/bitstream/1810/241039/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/5/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/6/thesis.pdf.jpg.

Council of Science Editors:

Shimwell TW. Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager. [Doctoral Dissertation]. University of Cambridge; 2011. Available from: http://www.dspace.cam.ac.uk/handle/1810/241039https://www.repository.cam.ac.uk/bitstream/1810/241039/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/5/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/241039/6/thesis.pdf.jpg

University of Toronto

28. Stein, George Frazer. Mocking the Universe: Accurate Simulations in the Era of Large-survey Precision Cosmology.

Degree: PhD, 2019, University of Toronto

URL: http://hdl.handle.net/1807/97685

► Efficient generation of accurate mock observations of the sky, tailored specifically to near-future large-scale structure and cosmic microwave background surveys, is a key technical challenge… (more)

▼ Efficient generation of accurate mock observations of the sky, tailored specifically to near-future large-scale structure and cosmic microwave background surveys, is a key technical challenge in cosmology. The increasing sensitivity and sky coverage of modern surveys probe unprecedentedly-large cosmological volumes, and when coupled with increases to angular resolution, demand simulations that are accurate to smaller scales, yet cover larger volumes, than ever before. The applications of such simulations are numerous, from performing cosmological parameter analysis, to optimizing survey designs and testing analysis pipelines, to making theoretical predictions, but to adequately perform these tasks requires state-of-the-art accuracy and computational efficiency. In this thesis we develop numerical simulations of cosmological structure formation to create synthetic observations, or mocks, of current and near-future cosmic microwave background and large-scale structure surveys. We first present our development and rigorous validation of the mass-Peak Patch method, a simulation technique to rapidly generate the large-scale structure of cosmological volumes for a fraction of the computational cost of alternative methods. Mass-Peak Patch is then used in union with a number of astrophysical sky models to produce the Websky extragalactic CMB simulations, a publicly released set of synthetic mocks of the extragalactic microwave to infrared sky. Next, we focus on the up-and-coming field of intensity mapping. We construct a suite of carbon monoxide line intensity maps, and use these to forecast the constraints on the CO luminosity function with near-future observations. Both the large data volumes and complicated statistical evaluations involved in standard cosmological analyses of survey data has recently led to the adoption of many machine learning methods throughout the field, and we finish this thesis with an investigation of machine learning methods in cosmology. We first overview machine learning in cosmology and discuss the viability and attractiveness of recently-popularized deep learning techniques, and then construct, train, and validate a convolutional neural network for the purpose of aiding cosmological simulations. Efficient simulation tools such as mass-Peak Patch, accurate mocks such as the Websky extragalactic maps, and machine learning techniques (when applied correctly), will enable precision analysis of the next generation of cosmological data sets. Advisors/Committee Members: Bond, J. Richard R, Astronomy and Astrophysics.

Subjects/Keywords: Astrophysics; Cosmology; 0596

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APA (6^th Edition):

Stein, G. F. (2019). Mocking the Universe: Accurate Simulations in the Era of Large-survey Precision Cosmology. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/97685

Chicago Manual of Style (16^th Edition):

Stein, George Frazer. “Mocking the Universe: Accurate Simulations in the Era of Large-survey Precision Cosmology.” 2019. Doctoral Dissertation, University of Toronto. Accessed March 04, 2021. http://hdl.handle.net/1807/97685.

MLA Handbook (7^th Edition):

Stein, George Frazer. “Mocking the Universe: Accurate Simulations in the Era of Large-survey Precision Cosmology.” 2019. Web. 04 Mar 2021.

Vancouver:

Stein GF. Mocking the Universe: Accurate Simulations in the Era of Large-survey Precision Cosmology. [Internet] [Doctoral dissertation]. University of Toronto; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1807/97685.

Council of Science Editors:

Stein GF. Mocking the Universe: Accurate Simulations in the Era of Large-survey Precision Cosmology. [Doctoral Dissertation]. University of Toronto; 2019. Available from: http://hdl.handle.net/1807/97685

University of Toronto

29. Inman, Derek Beattie. Nonlinear Dynamics of the Cosmic Neutrino Background.

Degree: PhD, 2017, University of Toronto

URL: http://hdl.handle.net/1807/80822

► At least two of the three neutrino species are known to be massive, but their exact masses are currently unknown. Cosmic neutrinos decoupled from the… (more)

▼ At least two of the three neutrino species are known to be massive, but their exact masses are currently unknown. Cosmic neutrinos decoupled from the rest of the primordial plasma early on when the Universe was over a billion times hotter than it is today. These relic particles, which have cooled and are now non-relativistic, constitute the Cosmic Neutrino Background and permeate the Universe. While they are not observable directly, their presence can be inferred by measuring the suppression of the matter power spectrum. This suppression is a linear effect caused by the large thermal velocities of neutrinos, which prevent them from collapsing gravitationally on small scales. Unfortunately, it is difficult to measure because of degeneracies with other cosmological parameters and biases arising from the fact that we typically observe point-like galaxies rather than a continous matter field. It is therefore important to look for new effects beyond linear suppression that may be more sensitive to neutrinos. This thesis contributes to the understanding of the nonlinear dynamics of the cosmological neutrino background in the following ways: (i) the development of a new injection scheme for neutrinos in cosmological N-body simulations which circumvents many issues associated with simulating neutrinos at large redshifts, (ii) the numerical study of the relative velocity field between cold dark matter and neutrinos including its reconstruction from density fields, (iii) the theoretical description of neutrinos as a dispersive fluid and its use in modelling the nonlinear evolution of the neutrino density power spectrum, (iv) the derivation of the dipole correlation function using linear response which allows for the Fermi-Dirac velocity distribution to be properly included, and (v) the numerical study and detection of the dipole correlation function in the TianNu simulation. In totality, this thesis is a comprehensive study of neutrino density and velocity fields that may lead to a new technique for constraining neutrino properties via the dipole correlation function. Advisors/Committee Members: Pen, Ue-Li, Physics.

Subjects/Keywords: Cosmology; Neutrinos; 0596

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APA (6^th Edition):

Inman, D. B. (2017). Nonlinear Dynamics of the Cosmic Neutrino Background. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/80822

Chicago Manual of Style (16^th Edition):

Inman, Derek Beattie. “Nonlinear Dynamics of the Cosmic Neutrino Background.” 2017. Doctoral Dissertation, University of Toronto. Accessed March 04, 2021. http://hdl.handle.net/1807/80822.

MLA Handbook (7^th Edition):

Inman, Derek Beattie. “Nonlinear Dynamics of the Cosmic Neutrino Background.” 2017. Web. 04 Mar 2021.

Vancouver:

Inman DB. Nonlinear Dynamics of the Cosmic Neutrino Background. [Internet] [Doctoral dissertation]. University of Toronto; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1807/80822.

Council of Science Editors:

Inman DB. Nonlinear Dynamics of the Cosmic Neutrino Background. [Doctoral Dissertation]. University of Toronto; 2017. Available from: http://hdl.handle.net/1807/80822

California State University – Chico

30. Williams, Sydney. The role of movement in Medieval Islamic cosmology as demonstrated by astrolabes and domes .

Degree: 2012, California State University – Chico

URL: http://hdl.handle.net/10211.4/457

► This thesis is a historical and cultural contextualization of both the astrolabe and the dome in medieval Islamic lands with particular emphasis on the relation… (more)

Subjects/Keywords: Islamic cosmology movement

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APA (6^th Edition):

Williams, S. (2012). The role of movement in Medieval Islamic cosmology as demonstrated by astrolabes and domes . (Thesis). California State University – Chico. Retrieved from http://hdl.handle.net/10211.4/457

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Williams, Sydney. “The role of movement in Medieval Islamic cosmology as demonstrated by astrolabes and domes .” 2012. Thesis, California State University – Chico. Accessed March 04, 2021. http://hdl.handle.net/10211.4/457.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Williams, Sydney. “The role of movement in Medieval Islamic cosmology as demonstrated by astrolabes and domes .” 2012. Web. 04 Mar 2021.

Vancouver:

Williams S. The role of movement in Medieval Islamic cosmology as demonstrated by astrolabes and domes . [Internet] [Thesis]. California State University – Chico; 2012. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/10211.4/457.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Williams S. The role of movement in Medieval Islamic cosmology as demonstrated by astrolabes and domes . [Thesis]. California State University – Chico; 2012. Available from: http://hdl.handle.net/10211.4/457

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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