Sci­ence: Test ‘ like the

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to en­crypt data, mak­ing them im­pos­si­ble to hack by con­ven­tional com­put­ers. They also have the abil­ity to alert au­thor­i­ties when some­one tries to eaves­drop, said Pan Jian­wei, an aca­demi­cian with the Chi­nese Acad­emy of Sciences and the chief physi­cist be­hind Mi­cius.

“This will have ma­jor ap­pli­ca­tions in gov­ern­ment, mil­i­tary, fi­nance, en­ergy and other fields where se­cu­rity is para­mount,” he added.

How­ever, dis­tribut­ing quan­tum keys is dif­fi­cult be­cause send­ing them over long dis­tances via fiber op­tics or dur­ing day­time re­sults in mas­sive sig­nal loss or dis­tur­bance.

In the lat­est quan­tum key ex­per­i­ment, Mi­cius beamed pho­tons — in­di­vid­ual par­ti­cles of light — and cre­ated an op­ti­cal link with the ob­ser­va­tory sta­tion in Xin­g­long, He­bei prov­ince. When the link was at 1,200 kilo­me­ters, sci­en­tists dis­cov­ered that quan­tum key dis­tri­bu­tion ef­fi­ciency be­tween the two im­proved 100 quin­til­lion times (1 fol­lowed by 20 ze­ros) com­pared with fiber op­tics of the same length.

Mi­cius pro­duced and trans­mit­ted about 300,000 bits of quan­tum keys dur­ing the ex­per­i­ment. One prac­ti­cal use for these keys is to cre­ate ad­vanced en­cryp­tions that are im­pos­si­ble for com­put­ers to hack with “brute force”, a method in which a com­puter guesses all pos­si­ble com­bi­na­tions of a pass code.

“Com­bine all the com­put­ing power of the world, which is around two to the power of 80 to 100, it will still take years for it to guess the cor­rect com­bi­na­tion,” Pan said.

The sec­ond ex­per­i­ment is about one of the big­gest mys­ter­ies of quan­tum me­chan­ics known as quan­tum tele­por­ta­tion, Ziemelis said. In the ex­per­i­ment, Chi­nese sci­en­tists “spook­ily” trans­ferred a pho­ton on Earth to Mi­cius in with­out need­ing the it­self to move.

“Its ef­fect is like the Star Trek tele­porter,” said Pan. It works by de­con­struct­ing a pho­ton on Earth, then send­ing its ex­tracted quan­tum in­for­ma­tion to Mi­cius’s re­ceivers via en­tan­gled link. Then an en­tan­gled pho­ton in space down­loads the in­for­ma­tion and takes on the com­plete iden­tity of the orig­i­nal.

This ex­per­i­ment would have great the­o­ret­i­cal re­search value in quan­tum sci­ence, as well as build­ing a large-scale quan­tum in­ter­net and com­pu­ta­tion net­works. But sci­en­tists are still cen­turies away from build­ing a tele­porter ca­pa­ble of trans­fer­ring some­thing as bi­o­log­i­cally com­plex as hu­mans, Pan said.

China also plans to build the world’s first global quan­tum com­mu­ni­ca­tion net­work by 2030. It will con­sist of three high-or­bit and dozens of lower-or­bit quan­tum space, ob­ject

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