Henry Bauer makes some pertinent comments but part of the reason there is so much controversy about the K-T extinction event is the fact that geological chronology has been stretched beyond reason, so that ‘events’ separated by millions of years of geological time inferred from sedimentary depositional rates, cannot be causal. And this is the problem – uniformitarian geochronology and the nonsense of ‘Dark Matter”. But then if we compressed the geological timescale I also doubt there would be any consensus on the cause of the K-T Extinction event, so the “dark matter” explanation would still be offered as one, of many, explanations.
Decades ago I arrived at the realisation that the dinosaur extinction event and the major eruption of kimberlite were causally related but quickly discovered that my peers held the view that we, as professional geoscientists, were not allowed to think such thoughts.
As HB writes,
A pervasive problem is that mainstream dogmas are taken as truth by people outside the particular field of knowledge: Randall is a physicist, so she is not familiar with the range of views among paleontologists and geologists.
Which all goes to show, as many others besides me have often remarked, that “What everyone knows is usually wrong (about science, say)”. On all but the most non-controversial issues, TED talks and Wikipedia entries are among the sources most likely to be wrong, moreover wrong dogmatically, insistently, aggressively, uncompromisingly, as they treat every contemporary (and thereby temporary) mainstream consensus as Gospel truth.
And of course self-published books, like “The Secret History of Twin Planet Earth”, for example, fall into the same trap HB describes above; authors who are absolutely certain of their opinions etc are often also quite wrong.