Olbers's Paradox

If the universe were eternal and infinite in all directions, then every line of sight from the Earth should eventually intersect a star and the entire sky should be as bright as the Sun. This has become known as Olbers's paradox (ca. 1826), although it had been addressed earlier by Kepler and Halley. Referring to what we actually see, this can also be called the "dark-night-sky paradox."
There is, as yet, no simple canonical resolution of the paradox, but one or more factors might be involved. Most fundamentally, astronomers and cosmologists now believe that the universe began with the Big Bang and is therefore finite in both space and time. But it might still be possible for an immensely large, though finite, number of stars to light up the sky. Some cosmologists suggest that the most distant stars might be receding faster than the speed of light, so that they are beyond the visible horizon. This might also be tied in with the universe's accelerating rate of expansion. Another contributing factor might be the red shift of light from the most distant stars, which might show up as a contribution to the cosmic microwave background (CMB).



  • [Snapshot]
  • [Snapshot]
  • [Snapshot]
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.

Mathematica »
The #1 tool for creating Demonstrations
and anything technical.
Wolfram|Alpha »
Explore anything with the first
computational knowledge engine.
MathWorld »
The web's most extensive
mathematics resource.
Course Assistant Apps »
An app for every course—
right in the palm of your hand.
Wolfram Blog »
Read our views on math,
science, and technology.
Computable Document Format »
The format that makes Demonstrations
(and any information) easy to share and
interact with.
STEM Initiative »
Programs & resources for
educators, schools & students.
Computerbasedmath.org »
Join the initiative for modernizing
math education.
Step-by-Step Solutions »
Walk through homework problems one step at a time, with hints to help along the way.
Wolfram Problem Generator »
Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet.
Wolfram Language »
Knowledge-based programming for everyone.
Powered by Wolfram Mathematica © 2018 Wolfram Demonstrations Project & Contributors  |  Terms of Use  |  Privacy Policy  |  RSS Give us your feedback
Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX
Download or upgrade to Mathematica Player 7EX
I already have Mathematica Player or Mathematica 7+