What is Cosmology: Definition and 925 Discussions

Cosmology (from Greek κόσμος, kosmos "world" and -λογία, -logia "study of") is a branch of astronomy concerned with the studies of the origin and evolution of the universe, from the Big Bang to today and on into the future. It is the scientific study of the origin, evolution, and eventual fate of the universe. Physical cosmology is the scientific study of the universe's origin, its large-scale structures and dynamics, and its ultimate fate, as well as the laws of science that govern these areas.The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia, and in 1731 taken up in Latin by German philosopher Christian Wolff, in Cosmologia Generalis.Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions of creation myths and eschatology.
Physical cosmology is studied by scientists, such as astronomers and physicists, as well as philosophers, such as metaphysicians, philosophers of physics, and philosophers of space and time. Because of this shared scope with philosophy, theories in physical cosmology may include both scientific and non-scientific propositions, and may depend upon assumptions that cannot be tested. Cosmology differs from astronomy in that the former is concerned with the Universe as a whole while the latter deals with individual celestial objects. Modern physical cosmology is dominated by the Big Bang theory, which attempts to bring together observational astronomy and particle physics; more specifically, a standard parameterization of the Big Bang with dark matter and dark energy, known as the Lambda-CDM model.
Theoretical astrophysicist David N. Spergel has described cosmology as a "historical science" because "when we look out in space, we look back in time" due to the finite nature of the speed of light.

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  1. RUTA

    Insights Dark Energy Part 1: Einstein-deSitter Cosmology

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  2. Arman777

    I Comoving Reference Frame in Cosmology

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  3. W

    I Understanding inflationary cosmology

    There is a prediction I have often hear about regarding inflationary cosmology but I am having trouble grasping what it really means. I am wondering if anyone could give a layman explanation fo the following : https://arxiv.org/pdf/1312.7619.pdf "Modes of a given (comoving) wavelength should...
  4. Arman777

    I Cosmology: Inertial Reference Frames & Misconceptions

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  5. FourEyedRaven

    Cosmology Exploring Cosmology through Challenging Problems: A Graduate-Level Workbook

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  6. J

    I Is the Brans-Dicke Vacuum Cosmology Theory Still Relevant?

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  7. P

    Schools How would you rate UC Davis' and U.H. at Manoa's Cosmology programs?

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  8. HaoBoJiang

    It's pleased to meet everybody

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  9. Arman777

    I Jeans Instability in an Expanding Universe

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  10. F

    A Force to fix sigma8 or A_s for Forecasts

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  11. S

    A Can there be a lawless universe (according to Hawking)?

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  12. MathematicalPhysicist

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  13. davenn

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  14. W

    I Understanding Loop Quantum Cosmology

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  15. S

    A According to Wilczek, how does quantum mechanics arise?

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  16. D

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  17. Arman777

    I What is the role of voids in the Hubble tension?

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  18. Arman777

    I Which redshift value is used in the velocity measurement of distance

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  19. W

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  20. J

    I Fulvio Melia's new argument for a linear cosmology

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  21. Arman777

    I Clarifying the Meaning of Radius of Curvature in Cosmology

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  22. F

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  23. S

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  24. S

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  25. S

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  26. S

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  27. TheMercury79

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  30. H

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  31. Arman777

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  32. Vick

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  33. J

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  34. S

    A Is Seth Lloyd's cosmological model background independent?

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  35. SJay16

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  36. SJay16

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  37. Arman777

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  38. Bandersnatch

    I Why is this Hubble plot linear for Omega=2 closed universe?

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  39. koulbichok

    I Gaussian probability distribution of formation PBH

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  40. koulbichok

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  41. J

    I Does the Friedmann vacuum equation have a linear solution?

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  42. Dark Energy, Cosmology part 2: Crash Course Astronomy

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    • madscientist404i
    • Media item
    • Astronomy Cosmology
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    • Category: Other Science
  43. Cerenkov

    B The singularities of gravitational collapse and cosmology

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  44. C

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  45. Jozefina Gramatikova

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  46. J

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  47. R

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  48. Jozefina Gramatikova

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  49. A

    Other Looking for a cosmology problem for pursuing my PhD

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  50. JD_PM

    What's book would you recommend on Cosmology?

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