expanding universe tagged posts

Researchers from the University of Southampton, together with colleagues from the universities of Cambridge and Barcelona, have shown it’s theoretically possible for black holes to exist in perfectly balanced pairs — held in equilibrium by a cosmological force — mimicking a single black hole.

Black holes are massive astronomical objects that have such a strong gravitational pull that nothing, not even light, can escape. They are incredibly dense. A black hole could pack the mass of the Earth into a space the size of a pea.

Conventional theories about black holes, based on Einstein’s theory of General Relativity, typically explain how static or spinning black holes can exist on their own, isolated in space...

An expanding, ring-shaped cloud of atoms shares several striking features with the early universe. (Credit: E. Edwards/JQI)

An expanding cloud of atoms could offer insight into unanswered cosmological questions. Researchers playing with a cloud of ultracold atoms uncovered behavior that bears a striking resemblance to the universe in microcosm. Their work, which forges new connections between atomic physics and the sudden expansion of the early universe, will be published in Physical Review X and highlighted by Physics.8

“From the atomic physics perspective, the experiment is beautifully described by existing theory,” says Stephen Eckel, an atomic physicist at the National Institute of Standards and Technology (NIST). “But even more striking is how that theory connects with cosmology.”

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