Is It Known For Sure Infinites In QFT Are Caused Using a Continuum?

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The discussion centers on the relationship between continuity in Quantum Field Theory (QFT) and the emergence of infinities, specifically UV and IR infinities. The author of "WHAT IS A QUANTUM FIELD THEORY?" argues that the idealization of physical space as R3 leads to diverging integrals, causing these infinities. It is confirmed that UV infinities arise from the continuum model, while IR infinities result from infinite spatial and temporal extensions. The Nielson-Ninomiya theorem is cited as a barrier to a fundamental lattice structure in spacetime, reinforcing the notion that unphysical bare coupling constants contribute to these infinities.

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I am reading WHAT IS A QUANTUM FIELD THEORY?" A First Introduction for Mathematicians.

The author states (2.4 Finite versus Continuous Models) that the use of continuity causes the infinities in QFT:

'Mathematicians are trained to think of physical space as R3. But our continuous model of
physical space as R3 is of course an idealization, both at the scale of the very large and
at the scale of the very small. This idealization has proved to be very powerful, but in the
case of Quantum Field Theory, it creates multiple problems, and in particular the infamous
infinities (in the form of diverging integrals).'

I think that, based on what I have read, it is a likely cause, but has it been proven?

It is not an issue in EFT because a cutoff is used to get finite answers. Could a cutoff be looked at as approximating a lattice model?

Thanks
Bill
 
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There are two kinds on infinities in QFT, UV infinities and IR infinities. UV infinities are due to using a continuum (in both space and time), while IR infinities are due to using infinite extension (in both space and time). And yes, it is known for sure that this is the case.
 
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I've always been under the impression that the Nielson-Ninomiya theorem precludes the possibility of spacetime having a fundamental lattice-type structure, and that the infinities that appear in QFT a result of using the unphysical bare coupling constants🤔
 
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