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Abstractions blog

A drawing of a mouse, with lines representing sensory data rotating 90 degrees to become lines of memory data.
neuroscience

The Brain ‘Rotates’ Memories to Save Them From New Sensations

April 15, 2021

Some populations of neurons simultaneously process sensations and memories. New work shows how the brain rotates those representations to prevent interference.

Illustration of a placenta that is a mosaic of different colors, with a connected fetus that is all one color.
genomics

New Genomic Study of Placenta Finds Deep Links to Cancer

April 8, 2021

A patchwork of genomic differences in the placenta may explain the organ’s “live fast, die young” strategy and its connections to cancer.

planetary science

Iceland’s Eruptions Reveal the Hot History of Mars

April 6, 2021

The new volcanic fissures are more otherworldly than they first appear.

A graphic showing that changing any of the digits of 505, 447 turns it into a composite number
prime numbers

Mathematicians Find a New Class of Digitally Delicate Primes

March 30, 2021

Despite finding no specific examples, researchers have proved the existence of a pervasive kind of prime number so delicate that changing any of its infinite digits renders it composite.

Spheres representing black holes, with small ones on top, large ones on the bottom, and one midsize example in the middle.
astrophysics

Long-Missing Midsize Black Hole Flashes Into View

March 29, 2021

Black holes seemed to come only in sizes small and XXL. A new search strategy has uncovered a black hole of “intermediate” mass, raising hopes of more to come.

Orange hills (polaritons) against a black background. Below each hill, an arrow points to an angular position on a circle.
explainers

The Near-Magical Mystery of Quasiparticles

March 24, 2021

The zoo of spontaneously emerging particlelike entities known as quasiparticles has grown quickly and become more and more exotic. Here are a few of the most curious and potentially useful examples.

A graphic showing improvements in the speed of matrix multiplication
algorithms

Matrix Multiplication Inches Closer to Mythic Goal

March 23, 2021

A recent paper set the fastest record for multiplying two matrices. But it also marks the end of the line for a method researchers have relied on for decades to make improvements.

An illustration of a bright blue flash in space.
astrophysics

New Kind of Space Explosion Reveals the Birth of a Black Hole

March 10, 2021

A supernova-like explosion dubbed the Camel appears to be the result of a newborn black hole eating a star from the inside out.

A house of cards propped up by a letter i, the unit of imaginary numbers.
quantum physics

Imaginary Numbers May Be Essential for Describing Reality

March 3, 2021

A new thought experiment indicates that quantum mechanics doesn’t work without strange numbers that turn negative when squared.