September 24, 2024: We are covering primordial black holes, the bird photographer of the year and why a great mathematician wanted a heptadecagon on his tombstone. —Robin Lloyd, Contributing Editor | | | If dark matter is made of black holes, then at least one atom-sized black hole flies through our inner solar system about once a decade, according to a new study covered by Scientific American editor Clara Moskowitz. These flybys could give scientists a chance to study so-called primordial black holes, which are an increasingly possible potential explanation for the universe's missing dark matter. Weakly interacting massive particles (WIMPs) were a fairly popular theoretical explanation for dark matter, the invisible mass that is known only from its gravitational influence on normal or visible matter. However, years of attempts to detect WIMPs have failed to turn them up. The newly identified opportunity to study primordial black holes in our "backyard" means scientists have a new way to look into what is responsible for dark matter.
What the experts say: "Everything is on the table because WIMPs have been put in such a corner, and they were the dominant paradigm for decades. Primordial black holes are really gaining popularity" as an explanation for dark matter, says astrophysicist Kevork Abazajian.
How it works: Tiny black holes likely have masses comparable to those of large asteroids and could be detected by measuring their gravitational impact on Mars and large moons. Scientists then could observe their trajectory to determine if they are asteroids or primordial black holes. | | | Bird Photographer of the Year | Winners of this year's Bird Photographer of the Year competition have captured both the beauty and the brutality of contemporary avian lives, writes Scientific American graphics intern Zane Wolf. There's more to say below, but first, you might want to click here and marvel at these incredible images. The entry that won gold, captured by Canadian photographer Patricia Seaton Homonylo, illustrates the sprawling tragedy of birds that die from collisions with glass windows, buildings and other structures. Somewhere between 100 million to one billion birds die annually from collisions with glass facades, Wolf reports.
Why this matters: A photograph of nature, or any subject, can seem as simple as a snapshot. But these images often require tedious hours and sometimes days of planning and patience. For some of the award-winning bird photos here, the work could have involved gaining familiarity with a bird's behavior, envisioning the photograph in the bird's absence, and awaiting the arrival of both the animal and the ideal ambient light.
What the experts say: "Photography competitions bring these spectacular images back into view and remind us that the world can be a magical place," Wolf writes. | | | • See-through wood is stronger than plastic and tougher than glass. | 6 min read | | | • The mathematician Johann Carl Friedrich Gauss (1777–1855) wanted a "regular heptadecagon," a 17-sided shape, on his tombstone, writes freelance math writer and puzzle creator Jack Murtagh. Read the essay to find out if his wish was granted, but why the 17-gon? Because Gauss picked up a problem left unanswered by the ancient Greek mathematician Euclid: which polygons can be constructed using only a compass and straightedge? In tackling that question, Gauss proved that the heptadecagon could be constructed with only a compass and straightedge if one relied on a complex equation that he arrived at to determine a line segment with a precise "special length." That length then enables the construction of the 17-gon using only the two tools. | 6 min read | | | —Robin Lloyd, Contributing Editor | | Subscribe to this and all of our newsletters . | | | | Scientific American
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