Asides
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Measuring black hole rotation halfway across the Universe
Astronomers measured the rotation of a black hole from halfway across the Universe. Astronomers have now used gravitational magnification to measure the rotation rate of a supermassive black hole in a very distant galaxy. From four separate images of the same black hole, R.C. Reis, M.T. Reynolds, J.M. Miller, and D.J. Walton found it was…
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Supernovas: mysterious and lumpy space explosions
Nearly every atom of your body was forged in a supernova explosion and dispersed into space. But how do massive stars explode? The details are complicated, pushing the limits of computer simulations and our ability to observe with telescopes. In the absence of very close-by events, the best data come from supernova remnants: the still-glowing…
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My dysfunctional relationship with dark energy
“Dark energy” is one of the more unfortunate names in science. You’d think it has something to do with dark matter (itself a misnomer), but it has the opposite effect: while dark matter drives the clumping-up of material that makes galaxies, dark energy pushes the expansion of the Universe to greater and greater rates. Though…
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Ionizing the Universe with black holes and neutron stars
About 380,000 years after the Big Bang, the Universe cooled off enough for stable atoms to form out of the primordial plasma. However, sometime in the billion years or so after that, something happened to heat the gas up again, returning it to plasma form. Though we know reionization (as it is called) happened, that…
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Emulating magnetic monopoles in Bose-Einstein condensates
Magnetic monopoles are hypothetical objects that act like the isolated north or south pole of a magnet. Ordinarily when you break a magnet in half, you end up with two smaller magnets, but some theories predict independent existence for monopoles — though they obviously must be rare in nature, because we haven’t seen one yet.…
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Studying electron motion in space and time
I really love how many experiments are beginning to probe to the limits of quantum measurement. I wrote about a pair of cool studies in December that revealed the quantum wavefunction — the mathematical structure governing the behavior of particles. Today, my latest article in Ars Technica examined a proposed experiment using X-ray lasers to…
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Ball lightning’s dirty secret is dirt
Ball lightning is weird: a spherical glowing object that zooms horizontally at a fast rate before vanishing. (I wonder how many UFO sightings are ball lightning.) It’s a rare phenomenon — far more so than ordinary lightning — so nobody had been able to measure its properties with scientific equipment until now. As it happened,…
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SUPERNOVA!
Pardon me, I’m a little excited. When I logged onto my computer this morning, I found that every astronomer and astronomy fan was talking about the same thing: a new observation of a probable white dwarf supernova in M82, also known as the Cigar Galaxy. This is exciting because M82 is practically a neighbor in…
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Sinners in the hands of an angry GLaDOS
It’s one of those nagging thoughts many of us have had: is our existence a reality or an illusion? Philosophers and scientists have grappled with the question, though today much of the discussion focuses on a related question: do we live in a computer simulation? In my (first hopefully of multiple) essays for Aeon magazine,…
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A glowing filament shows us where the dark matter hides
Astronomers have identified a filament in the cosmic web, which is the pattern formed by dark matter. That web in turn dictates the distribution of galaxies, since the dark matter attracts ordinary matter — atoms — through its gravity. However, it’s hard to spot the filaments connecting the different halos of dark matter, because…
Bowler Hat Science 