The Cosmic Microwave Background: Historical and Philosophical Lessons

This volume tells the untold story of how observations of the cosmic microwave background radiation were interpreted in the decades following its serendipitous discovery, before the Hot Big Bang model became the accepted orthodoxy. The authors guide the reader through this history, including the many false trails and blind alleys that occurred along the way. Readers will discover how the Big Bang theory was shaped by alternative theories that exposed its weaknesses – including some that persist even today. By looking carefully at what it takes to reject an incorrect theory and the assumptions and processes at each stage, the authors examine the epistemological factors at play between an emerging scientific orthodoxy and since discarded alternatives. Their analysis of the cosmic microwave background provides a uniquely well-documented case study of theory building for a wide readership spanning cosmology, the history of physics and astronomy, and the philosophy of science more broadly.

Table of Contents:
Introduction; Part I. Physical Cosmology: A Brief Introduction: 1. Physical cosmology from Einstein to 1965; 2. The 'great controversy' (1948–65) and epistemological issues it raised; 3. Hot big bang and λCDM; Part II. Discovery of the CMB and Current Cosmological Orthodoxy: 4. Discovery of the CMB; 5. CMB phenomenology; 6. Standard 'textbook' history and its shortcomings; 7. Emergence of precision cosmology; Part III. What Constitutes an Unorthodoxy? Epistemological Framework of Cosmology: 8. Underdetermination of theories and models in cosmology; 9. Was the CMB a smoking gun?; 10. Classifying and analysing unorthodoxies; Part IV. Moderate Unorthodoxies: The CMB with the Big Bang: 11. Cold and tepid big bangs: population iii objects; 12. Models with unresolved sources; 13. Thermalization by grains, the first wave; 14. Primordial chaos; 15. Early intergalactic medium, massive population III objects and the large-numbers hypothesis; 16. Late thermalization of starlight; 17. 'An excess in moderation': high-baryon universe; Part V. Radical Unorthodoxies: The CMB Without the Big Bang: 18. Motivations: who's afraid of the big (bad) bang?; 19. Hoyle-narlikar theory and the changing masses origin of the CMB; 20. Revised steady state; 21. Closed steady-state models; 22. CMB in plasma cosmology; 23. CMB in non-expanding models; Part VI. Formation of the Orthodoxy and the Alternatives: Epistemological Lessons: 24. History and epistemology: the emergence of orthodoxy; 25. What about the alternatives?; 26. Pragmatic aspects of model-building and social epistemology of cosmology; 27. Large-scale numerical simulations in cosmology: beyond the theory-observations distinction?; Part VII. Other Philosophically Relevant Aspects of the CMB: 28. CMB and copernicanism: 'the axis of evil' and 'the fingers of god'; 29. The 'problem of other observers' and anthropic reasoning; 30. The nature of boundary conditions in cosmology, the CMB, and the 'laws of nature' debate; 31. CMB and the multiverse: limits of scientific realism?; Appendix 1: relativistic cosmological models; Appendix 2: dipole anisotropy; Notes; References; Index.

About the Author :
Slobodan Perovic is a professor of philosophy and history of science at the University of Belgrade. . He earned his Ph.D. at York University, Toronto, in 2005, and held teaching and research positions at Carleton University and the University of Pittsburgh, before returning to join the faculty in Belgrade in 2010. He is the principal convener of the 'Philosophy of Scientific Experimentation' conference series, and is author of From Data to Quanta: Niels Bohr's Vision of Physics (University of Chicago Press, 2021). Milan M. Ćirkovic is a senior researcher at the Astronomical Observatory of Belgrade. He also holds an adjunct position at the Future of Humanity Institute, University of Oxford. He has broad research interests in applying philosophical ideas to diverse areas including astrobiology and global catastrophic risks. His previous books include The Astrobiological Landscape: Philosophical Foundations of the Study of Cosmic Life (Cambridge University Press, 2012) and The Great Silence: Science and Philosophy of Fermi's Paradox (Oxford University Press, 2018).

Review :
'The Cosmic Microwave Background by Slobodan Perovic and Milan M. Cirkovic is a very welcome addition to the recent literature on the history and philosophy of experiment. The central focus is on the role that the discovery of the Cosmic Microwave Background (CMB) played in the establishment of the currently accepted 'hot big bang' theory of the origin of the universe. The authors also devote considerable discussion to the explanations of the CMB provided by alternative models of the origin, illustrating the complex relation between evidence and theory in cosmology. The discussion of the historical and philosophical issues is clear and well-written and will be understandable and valuable to those who are not expert in physics and cosmology. I strongly recommend it.' Allan Franklin, University of Colorado, Boulder 'Perović and Ćirković weave a fascinating and nuanced tapestry of history and epistemology. Not only is the historical narrative valuable in its own right, but the book really shines because of the pay-offs for both philosophers and physicists that arise from its rich historical analysis. The real story of the cosmic microwave background, in all its gritty detail, ultimately provides an even stronger methodological underpinning than the pristine textbook version that the authors set out to rectify.' Niels Martens, Utrecht University 'As the subtitle states, this is a book on the history and philosophy of the CMB. However, it does not stray far from actual physics, and points are made with the help of concrete examples … The emphasis is on what the CMB can tell us about how science is (and has been) done … It is thus a good book for those with such knowledge who want to learn more about the history and philosophy of the field in the context of a concrete example …' Phillip Helbig, The Observatory