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Physics

See the latest physics news and expert analysis on dark matter, the multiverse, theoretical and particle physics, quantum theory, and more from the world of physics.

Physics

Time may be an illusion created by quantum entanglement

The true nature of time has eluded physicists for centuries, but a new theoretical model suggests it may only exist due to entanglement between quantum objects

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

Physics

Quantum time travel: The experiment to ‘send a particle into the past’

Physics

Quantum ‘arrow of time’ suggests early universe had no entanglement

Physics

Quantum to cosmos: Why scale is vital to our understanding of reality

2GFMTHY quantum computer

Physics

How quantum entanglement really works and why we accept its weirdness

Physics

X-ray laser fires most powerful pulse ever recorded

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Physics

What are fractals and how can they help us understand the world?

Physics

How indefinite causality could lead us to a theory of quantum gravity

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

Physics

Sunlight-trapping device can generate temperatures over 1000掳C

Physics

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

Physics

Being in two places at once could make a quantum battery charge faster

Physics

Fusion reactors could create ingredients for a nuclear weapon in weeks