Phys. Rev. Lett. 106, 243602 (2011)The press release from the Hong Kong University of Science and Technology of 19 July 2011 was titled "HKUST Professors Prove Single Photons Do Not Exceed the Speed of Light". Excerpt
Optical Precursor of a Single Photon
Shanchao Zhang, J. F. Chen, Chang Liu, M. M. T. Loy, G. K. L. Wong, and Shengwang Du*
Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
Received 31 March 2011; published 16 June 2011
We report the direct observation of optical precursors of heralded single photons with step- and square-modulated wave packets passing through cold atoms. Using electromagnetically induced transparency and the slow-light effect, we separate the single-photon precursor, which always travels at the speed of light in vacuum, from its delayed main wave packet. In the two-level superluminal medium, our result suggests that the causality holds for a single photon.
URL: http://link.aps.org/doi/10.1103/PhysRevLett.106.243602
DOI: 10.1103/PhysRevLett.106.243602
PACS: 42.50.Gy, 32.80.Qk, 42.50.Dv
*dusw@ust.hk
A group of physicists at the Hong Kong University of Science and Technology (HKUST) led by Prof Shengwang Du reported the direct observation of optical precursor of a single photon and proved that single photons cannot travel faster than the speed of light in vacuum. HKUST's study reaffirms Einstein's theory that nothing travels faster than light and closes a decade-long debate about the speed of a single photon.Read more. This was also reported by AFP via France 24, which made a rather assertive conclusion
Prof Shengwang Du, Assistant Professor in HKUST's Department of Physics, and his research team have published their study in Physical Review Letters recently. Co-authors include three postgraduate students Shanchao Zhang, Jiefei Chen and Chang Liu, Chair Professors Michael M T Loy and George K L Wong. This is the fifth time in the last two years that Prof Du's team published their optics research in Physical Review Letters, one of the most prestigious scientific journals in physics, and the second time their papers were selected as editors' suggestion for reading. This research was also highlighted as a Physics Synopsis by American Physical Society with a title "Single photons obey the speed limits."
Prof Du's study demonstrates that a single photon, the fundamental quanta of light, also obeys the traffic law of the universe just like classical EM waves. Einstein claimed that the speed of light was the traffic law of the universe or in simple language, nothing can travel faster than light. HKUST's team is the first to experimentally show that optical precursors exist at the single-photon level, and that they are the fastest part of the single-photon wave packet even in a so called 'superluminal' medium.
Hong Kong physicists say they have proved that a single photon obeys Einstein's theory that nothing can travel faster than the speed of light -- demonstrating that outside science fiction, time travel is impossible.Read more. Surely a single experiment proving that light (photon as a light particle) cannot travel faster than light would not rule out faster than light travel by other types of particles. In any case, there are other time travel theories that are not predicated on travelling at faster than the speed of light.
LONDON — Wearing their finest tweeds, stroking their sideburns and filling the air with pipe smoke, competitors and spectators gathered for The Chap Olympiad, an annual celebration of the classic English gentleman.
Hundreds of "chaps" and "chapettes" descended on a leafy square in central London on Saturday for the sporting social occasion, where regular pastimes are overlooked in favour of smoking pipes, ordering butlers about and swilling cocktails.
The event is the annual summer bash of The Chap, a bi-monthly magazine celebrating the English gent, his eccentricity, courteous behaviour, impeccable dress and devotion to facial hair. In its 12th year, it now has 10,000 readers.
"It's a sports day for people who don't like sport," said organiser Gustav Temple, The Chap's editor.
"It's unfair that chaps who spend most of their time filling their pipes, pressing their trousers and mixing dry Martinis don't get a chance to compete," he told AFP.
The 10 events include the pipeathlon -- sauntering, bicycling and being carried by servants while smoking a pipe -- butler baiting, ironing board surfing and moustache wrestling.
Read more.
Swedes throw away food for 20-40 billion kronor ($3-6 billion) every year and the food tossed aside by households, stores and restaurants is just the tip of the iceberg. A new report from the Swedish Board of Agriculture (Jordbruksverket) reveals that vegetables considered unattractive never even reaches stores.The Local also reported that one third of all food produced is not even eaten. Read more. Full report from Jordbruksverket, Hållbar konsumtion av jordbruksvaror linked here (pdf document in Swedish).
"A lot of carrots get thrown away because of their looks, and that just feels completely wrong considering today's debate about the environment," carrot farmer Tanya Hultman, outside Piteå in northern Sweden, told The Local on Thursday.
Carrots that don't make the cut are among the unappealing foodstuff most often rejected, according to Sveriges Radio (SR). Too small, too crooked, too big - none of these vegetables will see grocery stores.
Hultman is disappointed by this blatant discrimination, pointing out that there's nothing wrong with the carrots apart from looking insufficiently appealing.
According to the Swedish Board of Agriculture, as much as a fourth of all the carrots farmed are rejected by stores.
An Austrian atheist has won the right to be shown on his driving-licence photo wearing a pasta strainer as "religious headgear".Read more. Earlier reporting by AFP in France24 (12 July 2011), Der Spiegel (13 July 2011).
Niko Alm first applied for the licence three years ago after reading that headgear was allowed in official pictures only for confessional reasons.
Mr Alm said the sieve was a requirement of his religion, pastafarianism.
Later a police spokesman explained that the licence was issued because Mr Alm's face was fully visible in the photo.
"The photo was not approved on religious grounds. The only criterion for photos in driving licence applications is that the whole face must be visible," said Manfred Reinthaler, a police spokesman in Vienna.
He was speaking on Wednesday, after Austrian media had first reported Mr Alm's reason for wearing the pasta strainer.
After receiving his application the Austrian authorities had required him to obtain a doctor's certificate that he was "psychologically fit" to drive.
Eine kleine Pressemitteilung.Strangely, it's not a bad look. Fitting that the appropriate headwear for worship of the Flying Spaghetti Monster is one that is used to drain spaghetti.
—-
Morgen 8.30 Ad hoc PK: Die Nudelsieb-Affäre. Die Hintergründe.
Eine Beweisführung darüber, wie absurd Kirchenprivilegien heute sind. Mit Niko Alm und seinem Nudelsieb.
(Wien 13.7.11,) Wie es kam, dass ein Führerschein-Foto des Unternehmers Niko Alm mit Nudelsieb auf dem Kopf von der Behörde akzeptiert wurde – Niko Alm, Atheist und Mitinitiator des Volksbegehrens gegen Kirchenprivilegien, ist bekennender Pastafari und hat 3 Jahre lang um sein Recht auf einen Identitätsausweis mit Nudelsieb am Kopf gekämpft. Der Pastafarianismus wurde 2005 vom US- Physiker Bobby Henderson gegründet, Gottheit ist das Fliegende Spaghettimonster. Niko Alms Führerschein hat dieser Tage großes mediales Aufsehen erregt. Allerdings kann jeder das Privileg einer konfessionellen Kopfbedeckung am Passfoto in Anspruch nehmen. Niko Alm möchte aufzeigen, dass religiöse Privilegien vielfach aus dem Mittelalter kommen, oft skurril sind und im 21. Jahrhundert endlich beendet werden müssen.
Alles über das Recht aufs Nudelsieb und den seit heute laufenden Wettbewerb “Pimp your Head” – zeig die kreativste konfessionelle Kopfbedeckung, präsentiert von den Initiatoren des Volksbegehrens gegen Kirchenprivilegien.
Pressekonferenz und Fotoshooting:
morgen Donnerstag, 14.7., 8.30h
mit
Niko Alm, Unternehmer, Mitinitiator Volksbegehren gegen Kirchenprivilegien,
und
Univ. Prof. Heinz Oberhummer, Physiker und Wissenschaftskabarettist, Mitinitiator des Volksbegehrens gegen Kirchenprivilegien
Café Prückel
Stubenring 24 (Luegerplatz)
A-1010 Wien
Presse-Rückfragen:
FJ PUKARTHOFER PR, Jakob Purkarthofer, +43-664-4121491, info@purkarthofer-pr.at
On June 30, 2011, the world longest cross-sea bridge Shandong Hi-speed Jiaozhou Bay Bridge which is invested and operated by SDHS is officially open to traffic. Jiang Yikang, the secretary of the CPC Shandong Provincial Committee and director of the Standing Committee of the People's Congress of Shandong Province, Jiang Daming, the deputy secretary of the CPC Shandong Provincial Committee and governor of Shandong Province, general Wang Dengping, the political commissar of North China Sea Fleet, Li Qun, member of the Standing Committee of CPC Shandong Provincial Committee and secretary of CPC Qingdao Municipal Committee, Sun Liang, the Party secretary and chairman of board of SDHS as well as other members of the leadership lineup of SDHS are present at the opening ceremony.No doubt, the Chinese language version sounds even more 'official' and 'lofty'.
At 10:08 in the morning, accompanied by the martial music, the opening ceremony of Shandong Hi-speed Jiaozhou Bay Bridge grandly begins. Sun Liang and Li Qun deliver speeches in succession. At 10:30, Jiang Yikang announces the bridge is open to traffic. Immediately, the fireworks rise from all directions with doves flying into the sky. The cordial atmosphere floats over Jiaozhou Bay.
As the longest cross-sea bridge in the world, Shandong Hi-speed Bay Bridge is 41.58 Km long, whose opening to traffic realizes the dream of the people over the years in Qingdao, Huangdao and Hongdao and safeguards the economic development of Qingdao City. In addition, the construction of the bridge shows the strenth of SDHS and promotes the awareness and influence of SDHS.
Length: 26.4 miles (almost 3 miles longer than the previous record holder)Further information from SDHS on construction features and other details.
Width: Six-lane expressway
Capacity: Expected to carry over 30,000 cars a day
Tensile strength: Able to withstand earthquakes of 8.0 magnitudes on the Richter scale, strong typhoons and the impact of a 300,000 tonne vessel
Made up of: 450,000 tonnes of steel and 2.3 million cubic metres of concrete, supported by 5,200 columns
Built by: More than 10,000 workers
Built in: Four years
Importance: Reduces the distance between Quingdao city and the Huangdao district by around 18 miles
