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Re: orion 14C and falsifiability

On Sun, 19 Oct 1997 13:02:41 GMT +100, GD@teol.ku.dk writes:

   [... snip ... already seen ... great summaries presented...]


>Additional comments:

   [... Snip ...]

>  A single Qumran text date out of 19 texts dated that has 
>its two-sigma range in the 1st CE is not distinguishable in pattern 
>from what 19 uncontaminated 14C date measurements would produce 
>if all texts bore true dates in the 1st BCE.  (This is the distribution 
>pattern that would be predicted, in such a case.  That does not prove 
>that such a pattern of the texts' actual ages is true, however.)  
>(5) Bowing to the turmoil my post on the 4QpPsa 14C date caused, I 
>will change my wording if discussing this in the future:  I'll just call 
>it a data point which is inconvenient to my theory, report it as such, 
>acknowledge that if its true puts my theory out of business outright 
>and, since the text in question portrays a contemporary, living 
>Teacher of Righteousness, may also put Eisenman back into business in 
>a big way.  :-)  

   Given the number of texts and fragments involved, a larger sample would
   have been useful, but it's just as well until the contamination issue can
   be addressed.

>In the meantime, thanks to Sigrid and A. Lerner for their posts. 
>
>p.s. T.S., cigarette or smoke particulates are unlikely to have 
>contaminated scrolls 14C dates (or the Shroud of Turin 14C 
>dates) because that is the kind of thing the acid-base-acid lab cleaning 
>procedures are effective in taking out.

   I knew you'd give that answer, <VLSLG> Greg baby.  The acid cleaning
   is fatal to cloth and is truly only useful on larger pieces of leather.

  A second point is that 
>sample contamination, when it is a factor, generally has small effects--
>perhaps a century or two for a 1st CE item, rather than cutting an age 
>in half, i.e. from 1st CE to medieval.  This is simple physics on the 
>amount of contaminant in the carbon compared to the total quantity 
>of carbon being measured.

   Elsewhere, you haven't had contamination like you've heard described.  The
   amount of carbon in a .01 mm dia. string of fiber is small compared to  
   the equivalent volume of smoke residue.  Spread that residue over a fiber
   of noted value in a layer .0001mm thick but with three times the carbon
   content per volume of the fibre or leather fragment, the ratio of new to
   old carbon can easily be 1:1.  Surely you can calculate that one.  Py-
   thagoras could.

   Seriously, Greg.  Ask your experts how they would deal with fabrics you had
   just rescued from a room filled with smoke from a tar fire.

   Once I heard there was the real possibility of contamination, then new  
   techniques are needed.  Talk seriously with the lab.  Don't dance around
   this issue.
>
>Greg Doudna
>Copenhagen
>

Tom Simms