Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Eridanus Supervoid

  1. Dec 22, 2013 #1
    Hello,

    I came across a thread on Reddit the other day highlighting something that is either absolutely fascinating or bad reporting on what was said/found. I would really appreciate some discussion on the relevance and significance of the "Eridanus Supervoid".

    As far as I can tell it goes like this;

    The WMAP satellite data shows us that the average temperature of the universe is about 2.7K. There exists a large portion of the night sky that is significantly colder than it's surroundings ~70μK. If you look at a gaussian distribution of this data, the likelihood of this coldspot arising out of quantum fluctuations in the inflationary period are ~1.85%.

    The Wikipedia entry on this cites a controversial claim made by cosmologist Laura Mersini-Houghton that this cold spot could be explained by another universe pushing against our own. I assume it is considered controversial because most scientists in the field do not hold that view. She does however seem to think that her hypothesis can be tested.

    So, please could someone explain in layman's terms what the 'normal' causes of these cold spots are and what they think about this.

    http://en.wikipedia.org/wiki/CMB_cold_spot#Supervoid

    Thank you very much!

    BOAS
     
    Last edited: Dec 22, 2013
  2. jcsd
  3. Dec 22, 2013 #2

    Chronos

    User Avatar
    Science Advisor
    Gold Member

    The Eridanus supervoid has been steeped in controversy since its detection was announced. Probably the most stinging criticism was leveled in http://arxiv.org/abs/0908.3988, Disks in the sky: A reassessment of the WMAP "cold spot". A frenzy of papers followed both in condemnation and support of Zhang and Huterer. Among the more credible of these was http://arxiv.org/abs/1001.4758, Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Are There Cosmic Microwave Background Anomalies? They concluded there is no convincing statistical evidence of CMB anomalies.
     
  4. Dec 23, 2013 #3
    Thank you - I appreciate being able to see some of the discussion on both sides of the fence. It will however take me a while to get my head around these papers though, being a first year physics student :)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook