A good theory is an act of the informed imagination — it reaches toward the unknown while grounded in the firmest foundations of the known. In “Dark Matter and the Dinosaurs,” the Harvard cosmologist Lisa Randall proposes that a thin disk of dark matter in the plane of the Milky Way triggered a minor perturbation in deep space that caused the major earthly catastrophe that decimated the dinosaurs. It’s an original theory that builds on a century of groundbreaking discoveries to tell the story of how the universe as we know it came to exist, how dark matter illuminates its beguiling unknowns and how the physics of elementary particles, the physics of space, and the biology of life intertwine in ways both bewildering and profound.Supposedly she was going to call it "dark buzz", but she did not want to drive traffic to this blog. (Just kidding, Lisa.)
If correct, Randall’s theory would require us to radically reappraise some of our most fundamental assumptions about the universe and our own existence. Sixty-six million years ago, according to her dark-matter disk model, a tiny twitch caused by an invisible force in the far reaches of the cosmos hurled a comet three times the width of Manhattan toward Earth at least 700 times the speed of a car on a freeway. The collision produced the most powerful earthquake of all time and released energy a billion times that of an atomic bomb, heating the atmosphere into an incandescent furnace that killed three-quarters of Earthlings. No creature heavier than 55 pounds, or about the size of a Dalmatian, survived. The death of the dinosaurs made possible the subsequent rise of mammalian dominance, without which you and I would not have evolved to ponder the perplexities of the cosmos. ...
Randall calls the force driving that fraction “dark light” — an appropriately paradoxical term confuting the haughty human assumption that the world we see is all there is.
Not everyone accepts that a comet or asteroid wiped out the dinosaurs. A recent Time mag article said:
A new study examining volcanic eruptions and the infamous dinosaur-killing asteroid proposes a compromise in which both were responsible for the great extinction that occurred about 65 million years ago.So this may never be resolved.
In the study, published in the journal Science, Geologists examined the timing of the already well-researched volcanic activity in the Deccan Traps in western India, and found that those eruptions occurred within 50,000 years of the asteroid hit—a pretty narrow window in geologic time. The seismic punch of the impact may have accelerated the speed of the eruptions, making it not only likely that both events had a hand in the dinosaurs’ downfall, but difficult to tease out which, if either, was more to blame.
Randall is trying to be taken seriously, but wherever she goes to plug her book, the reporters spend most of their time asking her for stories about how male chauvinist physicists mistreated her, about how women are marginalized, and generally baiting her into talking feminist politics instead of physics. She is too polite to say so, but it is obvious that she is much more annoyed at how these reporters belittle women, than any gripes against physicists.
For an example, see The One Question This Brilliant Physicist Wants People To Stop Asking Her in the AOL Huff Post. I got suckered by the click-bait, as I wanted to see if the question was about Jodie Foster, who played a cosmologist in a movie based on a Carl Sagan book.
Other physicists are more political, and some are telling the US Supreme Court that we need affirmative action:
Minority students attending primarily white institutions commonly face racism, biases, and a lack of mentoring. Meanwhile, white students unfairly benefit psychologically from being overrepresented. ...This is just anti-white hatred. Physics has problems, but having too many white people is not one of them. Yes, most of the historical progress has been from white Christians and Jews, but not out of some white supremacy.
We ask that you take these considerations seriously in your deliberations and join us physicists and astrophysicists in the work of achieving full integration and removing the pernicious vestiges of racism and white supremacy from our world.