Showing papers on "Cosmography published in 2013"

Cosmographic Constraints and Cosmic Fluids

Abstract: The problem of reproducing dark energy effects is reviewed here with particular interest devoted to cosmography. We summarize some of the most relevant cosmological models, based on the assumption that the corresponding barotropic equations of state evolve as the universe expands, giving rise to the accelerated expansion. We describe in detail the CDM ( -Cold Dark Matter) and!CDM models, considering also some specific examples, e.g., Chevallier-Polarsky-Linder, the Chaplygin gas and the Dvali-Gabadadze-Porrati cosmological model. Finally, we consider the cosmological consequences off(R) andf(T ) gravities and their impact on the framework of cosmography. Keeping these considerations in mind, we point out the model-independent procedure related to cosmography, showing how to match the series of cosmological observables to the free parameters of each model. We critically discuss the role played by cosmography, as a selection criterion to check whether a particular model passes or does not present cosmological constraints. In so doing, we find out cosmological bounds by fitting the luminosity distance expansion of the redshift,z, adopting the recent Union 2.1 dataset of supernovae, combined with the baryonic acoustic oscillation and the cosmic microwave background measurements. We perform cosmographic analyses, imposing different priors on the Hubble rate present value. In addition, we compare our results with recent PLANCK limits, showing that the CDM and !CDM models seem to be the favorite with respect to other dark energy models. However, we show that cosmographic constraints on f(R) and f(T ) cannot discriminate between

Astrology and Cosmology in Early China: Conforming Earth to Heaven

Abstract: Introduction Part I. Astronomy and Cosmology in the Time of Dragons: 1. Astronomy begins at Taosi 2. Watching for dragons Part II. Aligning with Heaven: 3. Looking to the supernal lord 4. Bringing heaven down to earth 5. Astral revelation and the origins of writing Part III. Planetary Omens and Cosmic Ideology: 6. The cosmo-political mandate 7. The rhetoric of the supernal 8. Cosmology and the calendar Part IV. Warring States and Han Astral Portentology: 9. Astral prognostication and the battle of Chengpu 10. A new astrological paradigm Part V. One with the Sky: 11. Cosmic capitals 12. Temporality and the fabric of space-time 13. The sky river and cosmography 14. Planetary portentology east and west Epilogue Appendix. Astrology for an empire: the 'treatise on the celestial offices' in The Grand Scribe's Records (c.100 BCE) Glossary Index.

Science before Socrates: Parmenides, Anaxagoras, and the New Astronomy

Abstract: CONTENTS Introduction: Cosmic Conjunctions 1 Looking for Science 1.1 Unfounded speculation 1.2 Footnotes to Thales 1.3 Footnotes to Pythagoras 1.4 Science without knowledge 1.5 History of science without history 1.6 History of science without science 1.7 Old-time history of science Notes 2 Azure Pastures: An Early Ionian Model 2.1 Hesiod's mythical cosmography 2.2 Ionian theories 2.3 The Meteorological Model Notes 3 Borrowed Light: The Insights of Parmenides 3.1 Fifth-century advances 3.2 Three insights: Heliophotism, planetary unification, sphericity 3.3 The power of a model 3.4 Conjectures 3.5 Conceptual advances Notes 4 Empire of the Sun: Implications of Heliophotism, and a New Model 4.1 Antiphraxis and other theoretical implications 4.2 A new physics 4.3 Anaxagoras' new cosmology and astronomy 4.4 The Lithic Model Notes 5 Darkened Suns and Falling Stars: Heaven-sent Proofs 5.1 Lives of the eminent philosophers 5.2 Eclipses 5.3 The meteor 5.4 The comet 5.5 The Nile floods Notes 6 Lunar Revolutions: The Triumph of the New Astronomy 6.1 A community effort 6.2 Anaxagoras' theory 6.3 Other theories of the fifth century 6.4 Characteristics of the Lithic Model 6.5 The doxography 6.6 Plato's heavenly sphere 6.7 Aristotle's paradigm 6.8 A scientific consensus Notes 7 The Geometry of the Heavens 7.1 The story of early Greek astronomy 7.2 Scientific Progress 7.3 Historical and Philosophical Significance Notes Appendix 1: Anaxagoras in the Historiography of Science Notes Appendix 2: Science and History Notes Bibliography

The Politics of the Isolario: Maritime Cosmography and Overseas Expansion During the Renaissance

Abstract: Assessed as a series of narrative geographical constructs, isolarii reflect the diverse political and strategic agenda of the societies that produced and made use of them. Considering the geographical range covered by each isolario, their successive structure and contents, the article attempts to evaluate them as eclectic maritime cosmographies that sustained and supported the various workings of Western European overseas expansion from the early fifteenth century to the early seventeenth. The isolario is a cartographic encyclopaedia of islands, a particular genre that flourished during the Renaissance exploration of the maritime horizons. The isolario is a maritime cosmography, an erudite effort to chart the seas through the detailed cartographic presentation of sole fixed positions in the maritime flux: the islands. As a cultural construct, the isolario reflects the challenges of early modern cosmography, due to European expansion towards the east and west and the resulting altered perception of the world.1 It processes and promotes an alternative spatial system, varied and fragmentary, situated after the familiar continental frontiers. The isolario could be considered as a Humanistic project, an early modern echo of the ancient insular peregrinations narrated by Homer, Virgil and Apollodorus. It constitutes yet another combination of learned approach and empirical inspection. In fact, the isolario reflects a meeting among the various forces of rising modernity: the notions of connectivity imposed by merchants and navigators on the scattered image of the world; the political and economic prospects of maritime expansion; the development of long-distance communication networks; Humanism’s curiosity about geography, natural history and ethnography; the growing faith of the learned in tested and positive information; and the urge to provide administrators and men of action with useful, practical tools. The isolario is an artefact of early modern geographical culture, a Renaissance project that did not survive into the Age of Enlightenment, nor was it transmuted into another descriptive and cartographic geographical 1 See Frank Lestringant, “Le monde ouvert”, in Gérald Chaix (ed.), L’Europe de la Renaissance, 1470-1560, Nantes: Éditions du Temps, 2002, pp. 9-26 (especially pp. 18-19). The Historical Review / La Revue Historique Department of Neohellenic Research / Institute of Historical Research Volume IX (2012)

Constraints from Cosmography in various parameterizations

Abstract: We use cosmography to present constraints on the kinematics of the Universe without postulating any underlying theoretical model a priori. To this end, we use a Markov Chain Monte Carlo analysis to perform comparisons to the supernova Ia union 2 compilation, combined with the Hubble Space Telescope measurements of the Hubble constant, and the Hubble parameter datasets. The cosmographic approach to our analysis is revisited and extended for new notions of redshift presented as alternatives to the redshift z. Furthermore, we introduce a new set of fitting parameters describing the kinematical evolution of the Universe in terms of the equation of state of the Universe and derivatives of the total pressure. Our results are consistent with the \Lambda CDM model, although alternative models, with nearly constant pressure and no cosmological constant, match the results accurately as well.

Rethinking Romano-British *Corinium

Abstract: It is suggested that the name generally accepted as the Romano-British name of Cirencester, *Corinium, the traditional spelling deriving from a Latin rendering of that in Ptolemy’s Geography, is mistaken, and that for philologically sound reasons the authentic name is more likely to have been Cironium, as recorded in the Ravenna Cosmography.

Havre de Sylla on Jave La Grande

Abstract: The question of whether Portuguese navigators discovered Australia in the early sixteeth century is adressed. The Dieppe mappemondes that for some have provided an affirmative answer to this question are shown to be expressions of the cosmographic concepts of the period, thus accounting for the superficial resemblance of their Jave la Grande to Australia. Tracing the origin of their toponym Havre de Sylla shows how their Jave la Grande can be accounted for by developments in cosmography (including legends of the Three Magi and Saint Thomas), without the necessity of positing unrecorded voyages of discovery by Portuguese or other early sixteen-century voyagers.

On the Role of the Lotus Leaf in South Asian Cosmography

Abstract: As illustrated elsewhere (Kintaert 2010), the Indian lotus, Nelumbo nucifera subsp. nucifera Borsch & Barthlott, and different species of water lilies are frequently confused in secondary literature, despite their clear morphological differences.1 When studying any aspect of the cultural history of the Indian lotus it is therefore essential to take into account botanical data. Both the previous and the present article attempt this with regard to the leaf of the Indian lotus.2 Whereas the previous study focused on some secular uses of the lotus leaf, the present one is concerned with the lotus leaf ’s role in Vedic cosmogony and Epic-Purāṇic cosmography, dealt with in parts 2 and 3 respectively.3 Based on a specific morphological feature of young lotus leaves a hypothesis is pro-