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. Berenices

    Are Universal Oscillations Causing Changes in Cosmological Expansion?

    Hey all, I was reading up on some discoveries made in cosmology. http://iopscience.iop.org/1538-3881/149/4/137/ This could easily be due to observational error, but I was wondering whether something such as this is possible in our current models of expansion and dark energy without having to...
  2. Christian Grey

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    Suppose I am in a room and light(photons) from the light bulb reach my eyes, or I am outside light(photons) from the sun reach my eyes and I am able to see the objects around me. I want to know what factors affect the path of photons like temperature, gravity etc.I mean by knowing these factors...
  3. A

    Does universe expansion separate photons, traveling parallel?

    I understand that the force of gravity prevents galaxies from expanding, as space increases. However, I question if universal expansion separates photons (electromagnetism), as they are traveling along parallel paths (Would the normal distance between them increase over time)? Thank you.
  4. I

    Master Thesis Topic: GR & Statistical Mechanics

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  5. K

    The Entire Observable Universe

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  6. A

    What Comes Next After Secondary Education? A Senior's Dilemma

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  7. P

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  8. S

    Are there current efforts on ritz-type cosmology?

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  9. RyanH42

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  10. C

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  11. L

    Recent Early Universe Cosmology Review - Funding Essay

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  12. J

    Inflation & Pertubative 1st order Cosmology: A timeline?

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  13. logico

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  14. V

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  15. T

    Value of Cosmological Constant

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  16. U

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  17. Quarlep

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  19. D

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  20. Rajkovic

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  21. derbergfex

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  22. B

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  23. H

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  24. K

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  25. Ghostcrown

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  26. U

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  27. D

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  31. P

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  32. B

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  33. Quarlep

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  34. L

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  35. N

    Schools Graduate School Guidance. I want to be a cosmologist

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  36. C

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  37. P

    Engineering Which path should I choose? (Computer Engineering, Math, Cosmology ?)

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  38. wolram

    B What Is the Evidence for Dark Matter and Dark Energy?

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  39. T

    Covariance betw scalar amplitude & spectral index in Planck?

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  40. N

    Physics The Future of "Lone Physicists" - Researching Physics Alone?

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  41. marcus

    What can you learn about cosmology from Google calculator?

    Before I say, I just want to mention that the Danish words for 15 and 18 are femten and atten Atten sounds a bit like the English word "eighteen". So that is where we get our metric prefixes femto- for 10-15 and atto- for 10-18. When you do cosmology the most common quantity, or one of the...
  42. H

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  43. T

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  44. H

    Required backround for quantum cosmology

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  45. U

    Closed Universe - FRW Equation

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  46. P

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  47. G

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  48. Amrator

    Is Cosmology a Branch of Physics or Astronomy?

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  49. BilboBombadillo

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  50. B

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