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RXCYW8 Air conditioner units on a roof of industrial building

Environment

Cool solutions could head off the climate-damaging rush for air con

Demand for air conditioning will only grow as temperatures rise, sending energy consumption soaring. But there are some interesting ways to deal with the issue, finds Graham Lawton

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2CE844B Infinity tunnel pocket watch time, time travel concept

Physics

How physics is helping us to explain why time always moves forwards

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Artificial intelligence concept. Poster, wallpaper, Banner. Human body and brain glowing, 3d rendering. Human mental health, Mental balance, psychedelic trip effect, illusion of mind.

Life

Could we merge biologically with the fungal network and live forever?

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EM8P22 AshleyMadison.com, the dating site for primarily married people, is seen on Wednesday, April 15, 2015. Avid Life Media, the parent company of Ashley Madison, announced that it will be pursuing a initial public offering in London this year hoping to raise $200 million. (? Richard B. Levine)

Technology

What everyone gets wrong about the 2015 Ashley Madison scandal

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Marcadet Belv?d?re

Environment

Embrace wooden buildings for the sake of your health and the planet's

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This new visualization of a black hole illustrates how its gravity distorts our view, warping its surroundings as if seen in a carnival mirror. The visualization simulates the appearance of a black hole where infalling matter has collected into a thin, hot structure called an accretion disk. The black hole?s extreme gravity skews light emitted by different regions of the disk, producing the misshapen appearance. Bright knots constantly form and dissipate in the disk as magnetic fields wind and twist through the churning gas. Nearest the black hole, the gas orbits at close to the speed of light, while the outer portions spin a bit more slowly. This difference stretches and shears the bright knots, producing light and dark lanes in the disk. Viewed from the side, the disk looks brighter on the left than it does on the right. Glowing gas on the left side of the disk moves toward us so fast that the effects of Einstein?s relativity give it a boost in brightness; the opposite happens on the right side, where gas moving away us becomes slightly dimmer. This asymmetry disappears when we see the disk exactly face on because, from that perspective, none of the material is moving along our line of sight. Closest to the black hole, the gravitational light-bending becomes so excessive that we can see the underside of the disk as a bright ring of light seemingly outlining the black hole. This so-called ?photon ring? is composed of multiple rings, which grow progressively fainter and thinner, from light that has circled the black hole two, three, or even more times before escaping to reach our eyes. Because the black hole modeled in this visualization is spherical and non-rotating, the photon ring looks nearly circular and identical from any viewing angle. Inside the photon ring is the black hole?s shadow, an area roughly twice the size of the event horizon ? its point of no return. This visualization is ?mass invariant,? which means it can represent a black hole of any mass. The size of the black hole's shadow is proportional to its mass, but so is the size of the accreetion disk, so its properties scale accordingly. Simulations and movies like these really help us visualize what Einstein meant when he said that gravity warps the fabric of space and time.

Physics

How the weird and powerful pull of black holes made me a physicist

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Environment

Could we live in tree cities grown from giant sequoia in the future?

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Mind

How the US used science to wage psychological war

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Environment

Why carbon offsetting your flight isn't the answer

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View Los Angeles financial district skyline at night

Environment

The shift to LED lighting is stopping us from seeing our night skies

From an energy perspective, the move away from sodium vapour lamps to LEDs is great, but the news isn't so good when it comes to light pollution. The way we illuminate the world needs to be part of our green agenda, says Chanda Prescod-Weinstein

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Technology

Why curbing chatbots' worst exploits is a game of whack-a-mole

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Humans

Untangling the enigmatic origins of the human family’s newest species

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Environment

We can't get to net zero without tackling inequality

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Space

I might be an astrophysicist, but I'm still learning about stargazing

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