Why is the CMB fluctuation level 10^{-5}?

  title={Why is the CMB fluctuation level 10^\{-5\}?},
  author={Max Tegmark and Martin J. Rees},
W eexplorethequalitativechangesthatwould occuriftheam plitude Q (cid:24) 10 (cid:0) 5 ofcosm ologicaldensity (cid:13)uctuations were di(cid:11)erent. If Q (cid:24) < 10 (cid:0) 6 ,the cosm ologicalobjects that form would have so low virial tem peraturesthatthey m ay beunableto cooland form stars,and would beso loosely bound thateven if they could produce a supernova explosion,they m ightbe unable to retain the heavy elem entsnecessary forplanetary life. If Q (cid:24) > 10 (cid:0) 4 ,dense… 

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