Wednesday, December 30, 2009

Scientific American Jan 2010 & the Weak Nuclear Force

Contrary to the cover story in Scientific American's January 2010 issue, life would NOT be possible in a universe without the weak nuclear force, because then matter and antimatter would have completely annihilated each other, leaving no atoms to make life. Only the weak force treats matter and antimatter asymmetrically, allowing slightly more matter to develop in the first second after the Big Bang. Everything we see, and are made of, comes from that slight excess that the weak force enabled.


  1. Interesting. Could you please explain this a bit more? How does the weak force treat matter and antimatter asymmetrically?

    Al Moritz

  2. Hi Robert

    I just wrote something on this article for a history of science blog. It was brought to my attention as offering a solution to the 'fine tuning problem'.

    I have to say it felt like a bit of a hack job. What did you think of their suggestion that heavy water could act as a substitute for water as a universal solvent? I didn't really have much time to look into this in much detail but my impression was that heavy water in large quantities has the effect of slowing down a great many chemical reactions occurring in biological systems. Smaller forms of cellular life can adapt to this pretty well but more complex lifeforms get into difficulties.

  3. Hi Al

    I did see an article which mentioned this (in the Scientific American of all things).

    It seems to suggest the weak nuclear force causes a CP violation (but it says this would not have been strong enough to cause the matter/antimatter split).