Nature Astronomy recently published a new model, which explains the typical phenomena surrounding black holes: plasmatic outflows (winds). The article has been submitted by researchers from the US, Israel, Italy, and Greece.
The existence of black holes as a consequence of enormous gravity that prevents light from escaping had already been sighted at the end of the 18th century by the clergyman and philosopher John Mitchell and the mathematician Pierre-Simon Laplace. But it was only Albert Einstein’s theory of general relativity laid an ordered foundation for the phenomenon. At the beginning of the 20th century the physicist Karl Schwarzschild discovered the solution for the black hole in Einstein’s equations, though Einstein himself refused to believe in the existence of black holes in nature. Since then, there have been dramatic developments in this area, particularly a burgeoning of observable, clear and conclusive evidence for the existence of black holes.
One of the surprising phenomena observed in black holes is the strong winds that blow in their vicinity. The nature of these winds and the power, which drives them are explained in many ways, one of which describes them as a result of strong and regulated magnetic fields. The present article shows that the model of magnetic winds explains not only winds from super-massive black holes at the centers of galaxies, but also winds deriving from small black holes, whose mass resembles that of stars.
see the full story at the technion site
A research team led by Prof. Kinnert Keren and Prof. Erez Braun presented a new explanation for the rare regenerative ability of the Hydra
A study published February 7 in Cell Reports suggests that pieces of hydras have structural memory that helps them shape their new body plan according to the pattern inherited by the animal’s “skeleton.” Previously, scientists thought that only chemical signals told a hydra where its heads and/or feet should form.
see the paper in Cell Report
see more about it in The New York Times - How a Little Bit of Hydra Regrows a Whole Animal by James Gorman, The Scientist Magazine - Cytoskeletons Direct Hydra Regeneration by
Congratulations to Prof. Jeff Steinhauer for receiving The Henry Taub Prize for Academic Excellence. Jeff received this prize for his experimental work on the analog of Hawking radiation. Hawking radiation is supposedly emitted from a black hole, but it is much too weak to be detected experimentally. Instead, people look for physical systems analogous to a black hole which can emit similar radiation. Jeff developed an acoustic analog of a black hole using sound waves in a gas of cold atoms. These sound waves which Jeff detected are indeed very weak, having a temperature of nanokelvin. This discovery attests to Jeff’s talent as an experimental physicist.