[FOM] "Hidden" contradictions

[Timothy Y. Chow]

On Wed, 14 Aug 2013, Mark Steiner wrote:
> I appreciate this response.  However, my physicist friends tell me that 
> the theory known as QED is thought to be inconsistent, but people use it 
> anyway, with great success in predictions.  I think what this means is 
> the claim that there is no way to formalize QED in a consistent 
> axiomatic system.  If this is right, then there is a sense in which 
> formal systems do play some kind of role in physics.

The alleged inconsistency of QED is a complicated topic that has been 
discussed in great detail before on FOM and I don't think we want to 
rehash it all here, but I'll just say that even if we grant the (somewhat 
debatable) propositions that (1) "QED is thought to be inconsistent" and 
(2) this means that "there is no way to formalize QED in a consistent 
axiomatic system", then really all this shows is the exact opposite: 
namely, that formal systems *do not* play an important role in physics. 
If they did, then the physicists would be compelled to abandon QED.  The 
only role formal systems are playing here is in framing certain 
philosophical discussions *about* physics.

Tim