1 / 47

The Age of Things: Sticks, Stones and the Universe

The Age of Things: Sticks, Stones and the Universe. Distances, Redshifts and the Age of the Universe. http://cfcp.uchicago.edu/~mmhedman/compton1.html. WARNING! Cosmologist talking about Cosmology !. Last Time: Globular Clusters.

chantale-wooten
Download Presentation

The Age of Things: Sticks, Stones and the Universe

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Age of Things:Sticks, Stones and the Universe Distances, Redshifts and the Age of the Universe http://cfcp.uchicago.edu/~mmhedman/compton1.html

  2. WARNING! Cosmologist talking about Cosmology!

  3. Last Time: Globular Clusters 11.5  1.3 billion years 12  1 billion years 11.8  1.2 billion years 14.0  1.2 billion years 12  1 billion years 12.2  1.8 billion years Multiple analyses yield ages of 12-13 billion years, and an uncertainty of about 1 or 2 billion years M92 M68 M30 M13 NGC362 NGC6752

  4. Galaxies M87 Andromeda Whirlpool

  5. Galaxy Redshifts (Coutesy of E. Sheldon)

  6. The Spectra of different atoms Sodium Hydrogen Calcium Mercury Neon 400 500 600 700 Wavelength (nanometers)

  7. Galaxy Redshifts Hydrogen (Coutesy of E. Sheldon)

  8. Galaxy Redshifts Hydrogen Oxygen (Coutesy of E. Sheldon)

  9. Galaxy Redshifts Hydrogen Oxygen Wavelengths measured in Laboratory (Coutesy of E. Sheldon)

  10. Galaxy Redshifts Hydrogen Oxygen Wavelengths measured in Laboratory (Coutesy of E. Sheldon)

  11. The Doppler Effect

  12. Galaxy Redshifts Hydrogen Oxygen Wavelengths measured in Laboratory (Coutesy of E. Sheldon)

  13. Measuring the distance to the stars using Parallax Background Stars Nearby Stars Earth Earth Sun

  14. Estimating distance with brightness Sirius Pollux Castor Sirius B Luminosity = Total power emitted by star in the form of light.

  15. Galaxy Distances: Cepheids Large Magellanic Cloud

  16. The Period-Luminosity Relation of Cepheids More Luminous Less Luminous Based on Data from Udalski et. al. In Acta Astronomica Vol 49 (1999) pg 223

  17. The Period-Luminosity Relation of Cepheids More Luminous Less Luminous Cepheid in Galaxy: Period = 10 days Magnitude = 24 Cepheid in LMC: Period = 10 days Magnitude = 14

  18. The Period-Luminosity Relation of Cepheids More Luminous Less Luminous Cepheid in Galaxy: Period = 10 days Magnitude = 24 Cepheid in LMC: Period = 10 days Magnitude = 14 Same Luminosity 10,000 times fainter

  19. The Period-Luminosity Relation of Cepheids More Luminous Less Luminous Cepheid in Galaxy: Period = 10 days Magnitude = 24 Cepheid in LMC: Period = 10 days Magnitude = 14 Same Luminosity 10,000 times fainter 100 times farther away

  20. The Period-Luminosity Relation of Cepheids More Luminous Less Luminous Cepheid in Galaxy: Period = 10 days Magnitude = 24 Cepheid in LMC: Period = 10 days Magnitude = 14 Same Luminosity 10,000 times fainter 100 times farther away 150,000 light years away 15 million light years away

  21. Galaxy Distances: Type Ia Supernova Luminosity Supernova 1994D Days

  22. The Hubble Diagram Based on Data from Tonry et. al. astro-ph/0305008

  23. Now Then

  24. A special point in space implies anisotropies

  25. Large scale anisotropies are not observed Distribution of galaxies from the Sloan Digital Sky Survey

  26. General Relativity

  27. Classical Mechanics An object travels in a straight line at a constant speed unless acted upon by an outside force A force changes the motion of an object by an amount that depends on its mass

  28. Objects move differently due to their composition + - + + + + + + + Unless the force is gravity

  29. Gravity in Classical Mechanics The more massive object feels a sronger force The more massive object requires more force to accelerate it by the same amount

  30. Gravity in Classical Mechanics A A B B The presence of a massive object exerts a force that causes all objects to deviate from this path by the same amount With no outside forces, all particles take the path with the shortest distance between two points

  31. Gravity in General Relativity A A B B The presence of a massive object changes which path is the “shortest” distance between the two points With no outside forces, all particles take the path with the shortest distance between two points

  32. General Relativity Works It explains irregularites in Mercury’s orbit It predicted the gravitational lensing of starlight

  33. The Expanding Universe Now Then

  34. Re-interpreting the Hubble Diagram Based on Data from Tonry et. al. astro-ph/0305008

  35. Redshifts in an Expanding Universe Time 1 Time 2 Time 3

  36. Scale Factor a = 1 a = 0.5

  37. Re-interpreting the Hubble Diagram Based on Data from Tonry et. al. astro-ph/0305008

  38. Re-interpreting the Hubble Diagram Based on Data from Tonry et. al. astro-ph/0305008

  39. Re-interpreting the Hubble Diagram Based on Data from Riess et. al. astro-ph/0402512

  40. Re-interpreting the Hubble Diagram Based on Data from Riess et. al. astro-ph/0402512

  41. Extraopolating back to the Big Bang

  42. The Big Bang a = 1 a = 0.5 a = 0

  43. Extraopolating back to the Big Bang

  44. We need more information to do an accurate extrapolation

  45. No Talk Next Week June 5: Parametrizing the Age of the Universe

More Related