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Physics

Splash of a springboard diver

Physics

A microscopic diving board can cheat the second law of thermodynamics

Working with a tiny cantilever, physicists managed to violate the second law of thermodynamics, using less energy than expected to change the cantilever鈥檚 motion

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pocket watch

Physics

You can turn any random sequence of events into a clock

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Physics

Laser helps turn an electron into a coil of mass and charge

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New York Stock Exchange

Technology

Cosmic rays can help synchronise the global financial system

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Physics

Physicists determined the paper most likely to give you a paper cut

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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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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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2WG3YFC Titanium crater formed by a laser, SEM

Chemistry

Some metals actually grow more resilient when hot

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Physics

X-ray laser fires most powerful pulse ever recorded

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Physics

Physicists are grappling with their own reproducibility crisis

A contentious meeting of physicists highlighted concerns, failures and possible fixes for a crisis in condensed matter physics

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Physics

Doughnut-shaped swirls of laser light can be used to transmit images

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Physics

Quantum forces used to automatically assemble tiny device

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Physics

Physicists created an imaginary magnetic field in real life

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Physics

Physicists have worked out how to melt any material

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