Active Galactic Nuclei and Quasars: Why Still a Puzzle after 50 years?

Abstract

The first part of this article is a historical and physical introduction to quasars and their close cousins, called Active Galactic Nuclei (AGN). In the second part, I argue that our progress in understanding them has been unsatisfactory and in fact somewhat illusory since their discovery fifty years ago, and that much of the reason is a pervasive lack of critical thinking in the research community. It would be very surprising if other fields do not suffer similar failings.

26 pages, 2 figures, 1 appendix

References in corpus (6)

• A Continuum of H- to He-Rich Tidal Disruption Candidates With a Preference for E+A Galaxies
• Swift monitoring of NGC 5548: X-ray reprocessing and short term UV/optical variability
• The characteristic blue spectra of accretion disks in quasars as uncovered in the infrared
• The Mass and Spin of The Extreme Narrow Line Seyfert 1 Galaxy 1H 0707-495 and Its Implications for The Trigger for Relativistic Jets
• The changing X-ray time lag in MCG-6-30-15
• A panchromatic review of thermal and nonthermal active galactic nuclei

Cited by in corpus (7)

• Measuring the speed of light with ultra-compact radio quasars
• What controls the UV-to-X-ray continuum shape in quasars?
• Optical continuum photometric reverberation mapping of the Seyfert-1 galaxy Mrk509
• The Paschen Jump as a Diagnostic of the Diffuse Nebular Continuum Emission in Active Galactic Nuclei
• Automatized photometric monitoring of active galactic nuclei with the 46 cm telescope of the Wise observatory
• The relationship between variable and polarized optical spectral components of luminous type 1 non-blazar quasars
• The largest Swift AGN monitoring campaign: UV/optical variability in NGC 5548