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Message 1867953 - Posted: 18 May 2017, 15:38:47 UTC
Last modified: 18 May 2017, 16:55:58 UTC

King Abdullah II of Jordan has inaugurated Sesame, the Synchrotron Radiation Source built near Amman by an international partnership including Jordan, Israel,Iran, Cyprus, Turkey, Pakistan and the Palestinian National Authority. Its Scientific Director is Giorgio Paolucci who comes from the Elettra SRS built by Carlo Rubbia near Trieste, in Area Science Park where I worked.
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Message 1868420 - Posted: 20 May 2017, 16:43:29 UTC - in response to Message 1867953.  

King Abdullah II of Jordan has inaugurated Sesame, the Synchrotron Radiation Source built near Amman by an international partnership including Jordan, Israel,Iran, Cyprus, Turkey, Pakistan and the Palestinian National Authority. Its Scientific Director is Giorgio Paolucci who comes from the Elettra SRS built by Carlo Rubbia near Trieste, in Area Science Park where I worked.
Tullio

Yes Tullio.
When we where sitting in all our cathedrals the middle east was very much in to science.
Insha'Allah:)
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Message 1873697 - Posted: 17 Jun 2017, 23:30:15 UTC
Last modified: 17 Jun 2017, 23:31:45 UTC

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Message 1873833 - Posted: 18 Jun 2017, 14:31:12 UTC

I've tried to read the "Science" article, but it was not open. Let us wait for a next "Nature" article. From what I got so far, if you create a pair of entangled photons on a satellite and send photon A to a location on Earth and photon B at a different location, 1203 km away, when they arrive they are still entangled, so a measurement say of its polarization at location A determines its polarization at location B. This is what Einstein called "spooky action at distance".
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Message 1873837 - Posted: 18 Jun 2017, 14:40:52 UTC - in response to Message 1873833.  
Last modified: 18 Jun 2017, 14:41:20 UTC

How do they keep track of a particular photon--do you tag them. How do you synchronize your clocks to determine "instantaneous" state change. Maybe one side of the coin is "heads" and the other side is "tails" and when you look you may instantly assume that the other side is "heads". What is the process for entangling 2 photons?
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Message 1873844 - Posted: 18 Jun 2017, 15:17:36 UTC - in response to Message 1873837.  

I think the process for entangling 2 photons is to send a laser beam to a crystal which splits the beam, while maintaining the coherence. For details, I would like to read a more detailed description.
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Message 1873868 - Posted: 18 Jun 2017, 19:12:14 UTC

I think the quantum world is one of those places that is stranger than I can imagine. And I can imagine some pretty strange things.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
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Message 1873923 - Posted: 19 Jun 2017, 1:00:57 UTC

That was also Richard Feynman's opinion. You are in good company.
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Message 1873974 - Posted: 19 Jun 2017, 10:04:04 UTC

Richard Feynman’s apocryphal declaration: “If you think you understand quantum mechanics, you don’t understand quantum mechanics.”
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Message 1873977 - Posted: 19 Jun 2017, 10:24:59 UTC - in response to Message 1873868.  

I think the quantum world is one of those places that is stranger than I can imagine. And I can imagine some pretty strange things.


What bother's me most is that there are very few clear explanations about exactly what is the wierdness and how we know that it is wierd. Also why we think that quantum computers will work better that today's digital computers.
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Message 1873978 - Posted: 19 Jun 2017, 10:32:12 UTC - in response to Message 1873977.  

Quantum computers are ideally more powerful than today's computers. But as of today they do not exist, except in the marketing of D-Wave, a Canadian firm which has sold them to NASA and Google for a few million bucks.
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Message 1873979 - Posted: 19 Jun 2017, 10:47:03 UTC - in response to Message 1873977.  
Last modified: 19 Jun 2017, 11:05:46 UTC

There are some further explanations here.
http://indianexpress.com/article/explained/china-launches-quantum-communication-micius-satellite-2989406/
http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance
Quantum computers are very useful in finance and military cryptography applications.
You cannot eavesdrop the communication.
The quantum computer, which could decode current keys in a flash, lags far behind the simpler project of quantum key-pair encryption. The idea is to create and share a pair of entangled photons which serve as keys (Micius will beam photons to stations in China and Austria). A conventional key cannot signal that it has been cracked, but because of the observer effect, an attempt to intercept a quantum key would reduce it to junk data. So it’s the end of the line for bank fraud and online espionage, which infiltrate the web of trust which protects Internet communications.
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Message 1873981 - Posted: 19 Jun 2017, 12:20:47 UTC

Quantum cryptography is a reality used for keys distribution. Quantum computers are just laboratory experiments, with the possible exception of D-Wave, which is contested by scientists.
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Message 1877111 - Posted: 6 Jul 2017, 15:57:31 UTC

A new particle, made up from two "charm" quark and one "up" quark has been discovered by LHC in Geneva. The spokesman for the LHCb experiment, Giovanni Passaleva, has announced it at a meeting of The European Physical Society in Venice. The new particle is called Xicc++ and has a mass of 3621 MeV. The charm quarks are heavier than the up quark, so this is like a planet around a double star.
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Message 1877235 - Posted: 7 Jul 2017, 7:46:54 UTC

According to theregister.co.uk China's Experimental Advanced Superconducting Tokamak has reached a plasma temperature of 50 million Kelvin and maintained it for 101.2 s. If confirmed, this is a record for all Tokamaks.
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Message 1877418 - Posted: 8 Jul 2017, 6:57:54 UTC

So, does this mean that China will beat the rest of the world to a working fusion power plant?
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
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Message 1877424 - Posted: 8 Jul 2017, 8:10:44 UTC

They intend to go to a 1000 s of plasma confinement time and then build a demonstration plant. The only variable missing is the plasma density they have achieved. The Lawson criterion considers the product of plasma density, plasma temperature and confinement time, so I cannot tell if they have achieved the Lawson goal. But they seem to be on the right road and are certainly ahead.
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Message 1877530 - Posted: 8 Jul 2017, 23:15:11 UTC

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Message 1877571 - Posted: 9 Jul 2017, 7:44:32 UTC

ITER ia a big machine, but it is not a stellarator but a Tokamak. I've seen one of its superconducting magnets shipped from Liguria in Italy on a ship bound to Provence. The leading stellarator I know is Wendelstein II in Garching, Germany.
Tullio
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Message boards : Science (non-SETI) : Interesting Physics


 
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