Time is not instantaneous

Science Now today reports on a transitive photon entanglement experiment by Eli Megidish, Hagai Eisenberg, and colleagues at the Hebrew University of Jerusalem in which they show that two photons can be entangled even when they do not exist at the same time. Entanglement is explained by the conservation of energy, and their experiment suggests that this conservation does not have to be in an instant point.

They first create a pair of entangled photons 1 and 2, then they produce a second pair 3 and 4. Then they perform a "projective measurement" on photons 2 and 3, which entangles them. The entanglement property (polarization) of photon 1 is measured, which destroys it. When the entanglement 2, 3 is created after 1 has been measured, 1 and 4 have never coexisted at the same time as an entangled pair. By later measuring 4, the experiment shows that 1 and 4 are entangled.

In the middle, the article states correctly, that entanglement cannot be used to transmit information faster than the speed of light, but in the last paragraph this fact is contradicted. In reality, entanglement can be used to determine if a cipher has been read, but it cannot be used to transmit ciphers.

Link to the article: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

HB-SIA

Two weeks ago, Switzerland started its new international tourism campaign, projecting a quaint image invented by Romantic writers like Friedrich Schiller and Johanna Spyri, with a few chaps from the Outback fighting in a Schwingen match. This suits well with the political majority party, who would like to place a cheese cloche over the country so it can live in a bubble.

Meanwhile, the Swiss fret over the 2050 energy package, ratified 25 May 2011, after Fukushima and the decision to exit nuclear energy generation. The slogan is that of the 2000-Watt Society, in which each person does not use more than 2000 W per day (today's average is 6000 W) and emits less than 1 Ton of CO₂ per annum.

Such goals require the thought leadership of visionaries and effective demonstrators. Solar Impulse has been one of the best demonstrators. For example, in May 2012 it flew from Payerne across the Mediterranean to Rabat and Quarzazate, convincing the Moroccans that solar energy is the way of the future, supporting the plan by King Mohammed VI to construct the world’s largest thermo-solar power plant in Ouarzazate.

The visionaries behind Solar Impulse are Bertrand Piccard and André Borschberg, along with their sponsors and their big team.

The numbers of Solar Impulse are quite impressive: with a wingspan of 63.40 m it is the size of an Airbus A340 or a 747, but it weighs only 1,600 Kg, just a little more than a Prius. Its range is infinite, because it can fly perpetually, since it produces much more electricity than it consumes, just as the Swiss hope to do with their houses.

Currently Solar Impulse is in Hangar 2 at Moffett Federal Airfield at Ames Research Center, getting ready for the next mission.

Although the airplane can fly perpetually, in their 2015 flight around the world with the second model, license HB-SIB, Bertrand Piccard and André Borschberg will take turns every 5 days, because that is how long a trained human can stay awake and pilot, and also sit with very limited motion on the pilot seat/toilet combo:

On the first of May, Bertrand Piccard and André Borschberg will take off from Moffett Field at a speed of 44 km/h and fly their Across America mission, which will take them to Phoenix, Dallas, Saint Louis or Atlanta, Washington D.C., and finally JFK in New York City.

If you happen to look up and see a jumbo with license HB-SIA soaring silently at a speed of 70 km/h, think what you can do to give back more energy than you consume, so your total usage (think at those servers farms delivering your contents) is below 2000 W per day. In the case of the Solar Impulse, its 11,628 SunPower solar cells have an efficiency of 23% and drive the four brushless sensorless electric engines in addition of charging the batteries for when there is no sunlight.

Color naming 65,274,705,768 pixels

Where slide 6 is an approximate visualization of the spatial extent of the data analyzed.

Color naming 65,274,705,768 pixels from nmoroney

Alpine Internet Speeds

The Swiss Federal Office of Communications has published a map of telecommunications in Switzerland. The map can show television availability, upload and download speeds, connection types, and the number of providers, all at a resolution of 250 meters. The publication also provides a guide to broadband expansion projects taking place in Switzerland. The goal of the publication is to help plan broadband access projects and to help users make smart decisions regarding telecommunications.

Link to the tool: broadband map (in German, French and Italian)

Scaling body size fluctuation

Flocks of birds, schools of fish, and groups of any other living organisms might have a mathematical function in common. Studying aquatic microorganisms, Andrea Giometto, a researcher EPFL and Eawag, showed that for each species he studied, body sizes were distributed according to the same mathematical expression, where the only unknown is the average size of the species in an ecosystem.

Taken together, these observations of size distributions within a species and within all the species in a given ecological community have interesting implications. If in an ecosystem several species begin to converge around the same size, a balancing force will kick in to restore the power-law distribution, either by acting on the abundance or size of each species.

Finding power-laws and using them to describe complex systems already has a successful track record. “In physics, the observation that systems followed power-laws was instrumental in understanding phase transitions. We believe that power-laws can be similarly helpful to gain a deeper understanding of how systems of living matter work,” says Giometto, a physicist, who is seeking to apply methods from his field to understand biological ecosystems.

Link to the paper: Scaling body size fluctuations

Where is the sun?

When we take architectural pictures, we want to have the sun shining from the side, because this accentuates the edges. In the old days, this meant a shoot took two days, one to visit the sites of the buildings of interest to determine the best time, and a second day to do the actual shoots in a tour taking us to each building at the best time.

Today this is much easier. We can use an online tool like SunCalc to determine the best time.

In the box at the top left you enter the shoot location, then on the horizontal time scale you simply drag the orange dot. On the map, the thick orange segment indicates the sunlight direction. Just move the orange dot on the slider until the segment hits the façade more or less perpendicularly. You can enter the data into a spreadsheet, which you sort by the time, to get your itinerary.

By they way, the thin orange curve is the current sun trajectory, and the yellow area around is the variation of sun trajectories during the year. The closer a point is to the center, the higher is the sun above the horizon. The colors on the time slider above show sunlight coverage during the day.

Color language

Yesterday we received in the mail this year's first issue of the Atti della Fondazione Giorgio Ronchi (volume LXVIII). On pages 97–106 we found a paper by Lucia Ronchi with the intriguing title Familiarizing with color language I — Evolution and written language. This paper was instigated by the author's reading of Carole Biggam's recent book Semantics of Colour Vision.

Prof. Ronchi compares the frequency and category of color terms in a number of books in Italian, from the an early Psalterium through Dante to contemporary books. The work was accomplished by actually reading the texts and analyzing the color terms in reference to the surrounding text; a more detailed study is promised to appear in a second paper.

This detailed analysis of a few texts is rare in these days, where we tend to study large corpora using big data analytics, as we did for example in the post on which color synonym should I use?

Not having read Biggam's book, the article is in part a little obscure. For example, in the abstract we are given the expectation to read about the relation of studying color terms (linguistics) vs. color categories (cognition), but this is used only intrinsically. Also, we are promised a comparison between color terms and categories in the written and oral languages, but the article covers only the former.

Using Exchange process mailboxes with Java

In a world where servers are under constant attack, the wise will use the few facilities that can be easily hardened in a firewall and with defensive programming, like servlets. Sometimes it is useful to have something more simple than a web service, such as an email service. For example, you could take a picture with your mobile device and mail it to mostlycolor for a consultation by an automated color advisor.

It is easy to find the information to quickly code up an email client using the JavaMail API and the JavaBeans Activation Framework. Suppose your email is martin.muster@mostlycolor.ch with password !@#$% and your host is mailhub.mostlycolor.ch. You the access your mailbox with the simple statement

store.connect ("mailhub.mostlycolor.ch", "martin.muster@mostlycolor.ch", "!@#$%");

In practice, you do not want to use your mailbox for an automated service, but you want to use a so-called process mailbox on your Exchange server, say color.advisor@mostlycolor.ch. This seems obvious, but I was not able to formulate the correct query to find out how to access a process mailbox. Here is what I found out by trial and error.

Suppose your domain is americas and your login name is musterm. The connect statement then becomes

store.connect ("mailhub.mostlycolor.ch", "americas\\musterm\\color.advisor@mostlycolor.ch", "!@#$%");

Pretty simple once you know the syntax!

New SPIE open access program

As of January 2013, all new articles published in SPIE journals for which authors pay voluntary page charges are open access immediately on the SPIE Digital Library. SPIE asks journal authors (and their employers or other funders of their research) to provide such support to enable SPIE to hold down subscription prices and maximize access to the research published in SPIE journals. Many authors and institutions provide this support and will now obtain open access for their articles by doing so.

Increasingly, employers and research funders require authors to publish their articles with open access and authors want to do so in order to expand the reach of their research. SPIE provides the benefit of immediate open access for all articles for which voluntary page charges are paid. In these cases, authors retain copyright and SPIE licenses these articles under the Creative Commons Attribution license (CC-BY 3.0).

SPIE recognizes that researchers have modest funds to cover publication expenses. The voluntary page charges will continue to be low: $100 per published two-column page (for journals with both print and online formats) and $60 per published one-column page (for journals with an online format only).

For more information see http://spie.org/x85022.xml

from apprentice to master

When I grew up on the western edge of Lugano, life in the old country was not very mobile and people tended to spend their life at audible distance from the church bells they heard at birth. The most exotic person you could come across was that wiry old man in a tattered white suit hiking in the woods of Collina d'Oro that was Hermann Hesse, often carrying a drafting book and a box of water colors, totally absorbed in his thoughts.

With this, when Ravi Shankar came to town for a concert sponsored by Migros, it was like a little prince coming from an other planet. Indeed, he and his daughter were wearing traditional Indian clothing, something that had never been seen before on the streets of Lugano. I had the chance to spend a full day and an evening chatting with him, while conducting an interview for the youth radio and helping setting up the recording equipment for the concert.

I was amazed by the difference in personality between him and his daughter. The latter was distant and exotic, but Ravi Shankar was immediate and approachable. It was easy to talk casually with him. I had never seen a sitar before and started to talk with him about the complexity of the instrument. Since he was classically educated, I asked him how long it had taken him to become a master, compared to the piano or the violin. He countered he was not a master at all. When I noted his total command of the sitar and how he appeared to be one with it—even citing Jimi Hendrix and his electric guitar—he rebutted that he was just an apprentice. He continued that the sitar is an instrument that takes a whole life to learn to play, and it is only after reincarnation that one can play it as a master. He pointed out, that when performing on a complex instrument, total mental concentration was necessary and mastery of the sitar takes two lifetimes.

During the concert, I was at the left side of the first row and soon noticed that he was not only in constant musical contact with the other players, but he was also conversing with me through his eyes. Indeed, his protocol was to fixate a member in the audience he thought had an interesting posture, then fixate me, return to the first person to guide my gaze, and when I followed his gaze and looked at that person, he acknowledged with the hint of a smile. While Herman Hesse was totally absorbed in his thoughts, Ravi Shakar was involved concomitantly in three conversations—with the sitar, the orchestra, and the audience—meaning he had full awareness of his surrounding while he was also fully absorbed in the music.

Yesterday Ravi Shankar reached the end of his apprenticeship and today—12/12/12—he is a master sitar player.