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the economist
AS EVERY SCHOOLCHILD knows, some sorts of mathematics are harder than others. In the classroom, that is annoying. Outside, it can be useful. For instance, given two prime numbers, however large, multiplying them together to find their product is easy.
quantum  cryptography 
17 hours ago by geetarista
Enjoyed observation by Dr. Robert Sutor on computers: Quantum computing is not V2 of anything , it’s as if…
Quantum  from twitter_favs
2 days ago by leonsp
How Do You Take a Picture of a Black Hole? With a Telescope as Big as the Earth - The New York Times
near the core, that fog forms a great glowing Frisbee that rotates around a vast dark sphere. This is the supermassive black hole at the core of the Milky Way, the still point of our slowly rotating galaxy. We call it Sagittarius A*, that last bit pronounced “A-star.” The black hole itself is invisible, but it leaves a violent imprint on its environment, pulling surrounding objects into unlikely orbits and annihilating stars and clouds of gas that stray too close.

the inaugural run of the Event Horizon Telescope (E.H.T.), a virtual Earth-size observatory designed to take the first picture of a black hole. The E.H.T. uses a technique known as very long baseline interferometry (V.L.B.I.), in which astronomers at observatories on different continents simultaneously observe the same object, then combine the collected data on a supercomputer. The E.H.T.’s director, Shep Doeleman, a radio astronomer with the Harvard-Smithsonian Center for Astrophysics, likes to call the E.H.T. “the biggest telescope in the history of humanity.” It has the highest resolution of any astronomical instrument ever assembled. It’s sharp enough to read the date on a nickel in Los Angeles from New York, to spot a doughnut on the moon and, more to the point, to take a picture of the black hole at the center of our galaxy — or, at least, its shadow.

The effort to get that picture speaks well of our species: a bunch of people around the world defying international discord and general ascendant stupidity in unified pursuit of a gloriously esoteric goal. And in these dark days, it’s only fitting that the object of this pursuit is the darkest thing imaginable.

The physicist Werner Israel put it better when he described a black hole as “an elemental, self-sustaining gravitational field which has severed all causal connection with the material source that created it, and settled, like a soap bubble, into the simplest configuration consistent with the external constraints.”

what a black hole would look like if illuminated by the glow from the superheated matter swirling around it. He did his calculations by feeding punch cards into a primitive computer. He drew the results by hand. His black-and-white images looked like twisted depictions of a black Saturn, with a ringlike accretion disk warped like taffy.

That this shadow might be visible from Earth depended on an astonishing set of circumstances. Earth’s atmosphere happens to be transparent to the electromagnetic radiation — in this case, certain microwaves — shining from the edge of the black hole, even though it blocks radiation of slightly longer and shorter wavelengths. The interstellar gunk lying between Earth and the galactic center also becomes transparent at those frequencies, as do the clouds of superheated matter just outside the black hole, blocking a view of the event horizon. Later in life, Fulvio Melia compared this alignment to the cosmic accidents that give us total solar eclipses. The moon is just the right size, in just the right orbit, at just the right distance from Earth that now and then it blocks the sun entirely. Fulvio wasn’t religious, but these coincidences were so unlikely that he couldn’t help but feel that the black-hole shadow was meant to be seen. The universe had arranged for humans to see to the nearest exit.

it’s hard to reconcile two conflicting theories if you can’t find something wrong with either one, and quantum theory, like general relativity, has passed every test. As a result, scientists have been looking for ever-more-extreme situations in which to test these theories. That led them to black holes.

To avoid poisoning one another’s minds — so that no one could accidentally nudge another group into seeing a black-hole shadow that wasn’t really there — these groups worked in isolation, making images using different algorithms and techniques, trying hard to discredit anything that looked too sharp, too clean, too likely to be the product of wishful thinking.
telescope  astronomy  scientist  world  project  Physics  law  research  relativity  quantum 
5 days ago by aries1988
Graduate Student Solves Quantum Verification Problem
Urmila Mahadev spent eight years in graduate school solving one of the most basic questions in quantum computation.
quantum  crypto  computer 
6 days ago by cito
Graduate Student Solves Quantum Verification Problem | Quanta Magazine
Urmila Mahadev spent eight years in graduate school solving one of the most basic questions in quantum computation: How do you know whether a quantum computer has done anything quantum at all?
computing  cryptography  quantum  Verification 
8 days ago by gdw
How Quantum Computers Will Revolutionize Artificial Intelligence, Machine Learning And Big Data
via Pocket - How Quantum Computers Will Revolutionize Artificial Intelligence, Machine Learning And Big Data - Added July 20, 2018 at 08:13AM
IFTTT  Pocket  ai  article  quantum  computer  tech 
9 days ago by church7

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