He's a DeNiAr who "contributes" to Forbes. See the comment section.
The linear-no-threshold (LNT) theory is a theory (an explanation) of how radiation leads to cancer.
It is based on a number of tested hypotheses (facts) such as the energy required to damage DNA, the study of A-bomb survivors, etc. LNT as a hypothesis, is tested in each of those studies.
LNT is also a model...a model of reality based on the facts at hand, and a mathematical model in that we can use the risk estimates estimated for the A-bomb survivors and apply them to other cohorts, knowing that we may have to revise those estimates based on underlying cancer incidence.
Conca claims evolution is a fact. Really? I don't see dinosaurs evolving into birds. Evolution is a theory (an explanation) based upon a number of observable facts (like fossils, genetics, etc.). We can test evolutionary hypotheses, like the genetic similarity between chimps and humans. But that doesn't make evolution a fact, it makes the genetic similarity a fact.
That fact (tested hypothesis) adds to our theoretical framework of evolution. If we couldn't perform a genetic test due to lack of technology, then the hypothesis would be meaningless, but our theory would still be evolution, based on other tested hypotheses.