It is already used in Swiss elections to ensure that electronic vote data is securely transmitted to central locations. And as far as we know, no current quantum cryptographic system has been compromised in the field. This may be due to the work of security researchers who spend all their waking moments—and quite a lot of their non-waking moments—trying to pick the lock on quantum systems.
Their general approach can be summed up as follows: if you can fool a detector into thinking a classical light pulse is actually a quantum light pulse, then you might just be able to defeat a quantum cryptographic system. But even then the attack should fail, because quantum entangled states have statistics that cannot be achieved with classical light sources—by comparing statistics, you could unmask the deception. In the latest of a series of papers devoted to this topic, a group of researchers has now shown that the statistics can also be faked.
Quantum cryptography relies on the concept of entanglement. With entanglement, some statistical correlations are measured to be larger than those found in experiments based purely on classical physics. Cryptographic security works by using the correlations between entangled photons pairs to generate a common secret key. If an eavesdropper intercepts the quantum part of the signal, the statistics change, revealing the presence of an interloper.
But there's a catch here. I can make a classical signal that is perfectly correlated to any signal at all, provided I have time to measure said signal and replicate it appropriately. In other words, these statistical arguments only apply when there is no causal connection between the two measurements.
You might think that this makes intercepting the quantum goodness of a cryptographic system easy. But you would be wrong. When Eve intercepts the photons from the transmitting station run by Alice, she also destroys the photons. And even though she gets a result from her measurement, she cannot know the photons' full state. Thus, she cannot recreate, at the single photon level, a state that will ensure that Bob, at the receiving station, will observe identical measurements.
That is the theory anyway. But this is where the second loophole comes into play. We often assume that the detectors are actually detecting what we think they are detecting. In practice, there is no such thing as a single photon, single polarization detector. Instead, what we use is a filter that only allows a particular polarization of light to pass and an intensity detector to look for light. The filter doesn't care how many photons pass through, while the detector plays lots of games to try and be single photon sensitive when, ultimately, it is not.
It's this gap between theory and practice that allows a carefully manipulated classical light beam to fool a detector into reporting single photon clicks.
Since Eve has measured the polarization state of the photon, she knows what polarization state to set on her classical light pulse in order to fake Bob into recording the same measurement result. When Bob and Alice compare notes, they get the right answers and assume everything is on the up and up.
The researchers demonstrated that this attack succeeds with standard (but not commercial) quantum cryptography equipment under a range of different circumstances. In fact, they could make the setup outperform the quantum implementation for some particular settings.
The researchers also claim that this attack will be very difficult to detect, but I disagree. The attack depends on very carefully setting the power in the light beams so that only a single photodetector is triggered in Bob's apparatus. Within the detector, the light beam gets divided into two and then passed through polarization filters and detected. For a single photon beam, this doesn't matter—only one detector can click at any one time. But Eve's bright bunch of photons could set multiple detectors clicking at the same time. If you periodically remove filters, then Eve will inadvertently trigger more than a single photodiode, revealing her presence.
Richard Buckminster Fuller, c. 1917. Born: July 12, 1895 Milton, Massachusetts, United States Died: July 1, 1983 (aged 87) Los Angeles, United States Occupation: designer, author, inventor Spouse: Anne Fuller Children 2: Allegra Fuller Snyder and Alexandra who died in childhood
Full Text COPYRIGHT World Future Society 1989
The Birth of The Geodesic Dome
Although Buckminster Fuller invariably maintained that he was a comprehensivist who was interested in almost everything, his life and work were dominated by a single issue: shelter and housing. Even as a young boy in the early 1900s, Fuller--who preferred to be called Bucky--was constructing rudimentary structures and inventing better "environment controlling artifacts."
The practical culmination of his quest to employ modern assembly-line manufacturing techniques and the best man-made materials in producing inexpensive, elegant housing came toward the end of World War II. At that time, government officials contracted Fuller to build two prototype Dymaxion Houses at the Beech Aircraft Company in Wichita, Kansas.
The lightweight, circular houses were praised by all who toured them. Because the Dymaxion House was to provide many new innovations at the very affordable suggested retail price of $6,500, orders flowed into the factory before plans for distribution were seriously considered. However, Fuller's interests were not geared toward practical matters such as financing and marketing, and the
Dymaxion House never advanced beyond the prototype stage. Fuller then moved on to consider other innovations that could benefit humanity in the areas of structure and housing.
He also returned to his less pragmatic quest to discover nature's coordinate system and employ that system in a structure that would, because it was based on natural rather than humanly developed principles, be extremely efficient. That structure is the geodesic dome, which, because it approximates a sphere, encloses much more space with far less material than conventional buildings.
In order to uncover nature's coordinate system, Fuller retreated from a great deal of his usual activities during 1947 and 1948. The primary focus of that retreat was a single topic: spherical geometry. He chose that area because he felt it would be most useful in further understanding the mathematics of engineering, in discovering nature's coordinate system, and eventually in building the spherical structures that he found to be the most efficient means of construction.
Dome Models
Having observed the problems inherent in conventional construction techniques (as opposed to the ease with which nature's structures are erected) and the indigenous strength of natural structures, Fuller felt certain that he could perfect an analogous, efficient, spherical-construction technique. He was also aware that any such method would have to be predicated upon spherical trigonometry. To do that, Bucky converted the small Long Island apartment that his wife, Anne, had rented into a combination workshop and classroom where he studied and discussed his ideas with others.
As those ideas started to take shape in the models and drawings he used for sharing his insights, Fuller considered names for his invention. He selected "geodesic dome" because the sections or arcs of great circles (i.e., the shortest distance between two points on a sphere) are called geodesics, a term derived from the Greek word meaning "earth-dividing." His initial dome models were nothing more than spheres or sections of spheres constructed from crisscrossing curved pieces of material (each of which represented an arc of a great circle) that formed triangles. Later, he expanded the concept and formed the curved pieces into even more complex structures such as tetrahedrons or octahedrons, which were then joined to create a spherical structure. Still, the simple triangulation of struts remained, as did the initial name of the invention.
Although Fuller's study of mathematics played a significant role in his invention of the geodesic dome, that process was also greatly influenced by his earlier extensive examination of and work within the field of construction. During his construction experience, he came to realize that the dome pattern had been employed, to some extent, ever since humans began building structures. Early sailors landing upon foreign shores and requiring immediate shelter would simply upend their ships, creating an arched shelter similar to a dome.
Land-dwelling societies copied that structure by locating a small clearing surrounded by young saplings and bending those uncut trees inward to form a dome that they covered with animal skins, thatch, or other materials. Over time, that structure developed into the classic yurt that still provides viable homes for many people in and around Afghanistan and the plains of the Soviet Union.
Scientists are reporting development of a fast, reliable new test that could help people avoid a terrible type of food poisoning that comes from eating fish tainted with a difficult-to-detect toxin from marine algae growing in warm waters. The report appears in ACS' journal Analytical Chemistry.
Takeshi Yasumoto and colleagues explain that 20,000-60,000 people every year come down with ciguatera poisoning from eating fish tainted with a ciguatoxin -- the most common source of food poisoning from a natural toxin. Fish, such as red snapper and sea bass, get the toxin by eating smaller fish that feast on marine algae that produce the toxin in tropical and subtropical areas, such as the Gulf Coast of the U.S. There's no warning that a fish has the toxin -- it smells, looks and tastes fine. But within hours of ingesting the toxin, people with ciguatera have symptoms that often include vomiting, diarrhea, numbness or tingling in the arms and legs and muscle and joint aches. Debilitating symptoms may last for months. The current test for the toxin involved giving it to laboratory mice and watching them for symptoms. It is time-consuming, may miss the small amounts present in fish, and can't tell the difference between certain forms of the disease. That's why Yasumoto's group developed a faster, more sensitive test.
They describe development of a new test, using standard laboratory instruments, that avoids those draw backs. Yasumoto's team proved its effectiveness by identifying 16 different forms of the toxin in fish from the Pacific Ocean. Clear regional differences emerged -- for example, snappers and groupers off Okinawa shores had one type, whereas spotted knifejaw captured several miles north of Okinawa had another type. They also identified 12 types of toxin in a marine alga in French Polynesia, which could be the primary toxin source. The researchers say that the method outperforms current detection methods and in addition to helping diagnose patients, it will also help scientists study how the toxins move through the food chain from one animal to another.
Ziarul Der Spiegel a dezvaluit ca 27 din cei 72 de deputati ai partidului Die Linke (Stânga), care reprezinta peste o treime din întregul grup parlamentar, inclusiv vicepresedinta parlamentului, Petra Pau, fac obiectul unei supravegheri. Ministrul justitiei si omologul sau de la dezvoltare au considerat masura 'intolerabila', în timp ce ministrul de interne o considera justificata, noteaza miercuri ziarul La Vanguardia.
Desi este un lucru stiut si tolerat de mult timp de parlamentari, de data aceasta reactia a fost virulenta. Gregor Gysi, seful grupului parlamentar al partidului Die Linke si unul dintre supravegheati spune ca 'Bundestagul ar trebui sa controleze serviciile secrete, nu invers' si a trimis o scrisoare cancelarului, presedintelui federal si presedintelui parlamentului. Acesta si-a exprimat întelegerea fata de cei afectati, ca si unii reprezentanti ai Verzilor si ai SPD, ceea ce este o noutate. Potrivit Bundesamt für Verfassungsschutz (BfV), supravegherea se limiteaza la urmarirea activitatilor si declaratiilor lor publice, dar Gysi spune ca sunt minciuni, având în vedere ca supraveghearea include 'metode specifice serviciilor secrete'.
Vicepresedinta parlamentului german si deputat al partidului Die Linke (Stânga), Petra Pau. (Boris Streubel / Bongarts / Getty Images)
Multi deputati cred ca telefoanele si computerele lor sunt urmarite, desi nu se recunoaste. Supravegherea pleaca de la supozitia ca cei urmariti reprezinta un 'pericol' la ordinea stabilita si merita sa fie supravegheati asemeni neonazistilor. Chiar daca incompetenta ambigua a BfV fata de cei din urma a fost amplu dovedita în noiembrie. Atunci s-a aflat ca principalul grup de nazisti din tara au ucis în ultimii 20 de ani zece persoane, au comis numeroase jafuri si atentate cu bomba, fara sa fie descoperiti, desi în anturajul lor erau infiltrati informatori si agenti ai BfV, sau poate tocmai de aceea.
Umbra acelui caz, alaturi de supravegherea deputatilor, este cea care irita acum spiritele. BfV recunoaste cheltuirea a 360.000 de euro pe an pentru supravegherea partidului Die Linke, un amestec de social-democrati si post-comunisti. Cu o suta de mii mai putin decât cei folositi la supravegherea nazistilor din NPD. Potrivit lui BfV este vorba de 'extremisti' de stânga, iar faptul ca Petra Pau a fost aleasa cu votul a peste jumatate din Bundestag, pentru a ocupa functia, este irelevant fata de imperativul de 'protectie constitutionala' care intra în sarcina serviciilor secrete. Este vorba si de reminiscenta unei traditii, care dateaza de pe vremea autocratiei prusace, potrivit careia statul este o institutie superioara, anterior, drepturilor.
Are însa legatura si cu metodele de intimidare folosite de presa si institutii fata de singurul partid politic care pune în chestiune aspecte centrale ale establishment-ului german, precum austeritatea neoliberala, folosirea armatei în razboaiele de dupa 1999, sau solidaritatea cu Palestina, chestiuni care atrag acuzatii kafkiene de antisemitism din partea mass-mediei. Marti s-a aflat si ca din 2008 politia berlineza a strâns peste 4 milioane de date, prin conectarea la telefoanele mobile, pentru a întocmi o lista de persoane si adrese aflate în apropierea locurilor în care au fost incendiate masini. În pofida acestui abuz, nu a reusit sa identifice niciun singur suspect legat de incendierea a peste 500 de masini care ard anual în Berlin.
Sognatori, mettetevi l’anima in pace. Scettici, forse avete ragione voi. Timorosi, non c’è nulla di cui aver paura. Gli alieni non esistono, parola di Casa Bianca. Non c’è alcuna prova a favore dell’esistenza di vita extraterrestre e “ nulla che faccia pensare a un tentativo da parte del Governo statunitense di nascondere informazioni all’opinione pubblica”, scrive Phil Larson, della White House Office of Science and Technology Policy, in una nota pubblicata sulla pagina web della casa più famosa del mondo.
In un momento così delicato per gli equilibri politici ed economici del pianeta, ci si domanda perché mai l’amministrazione Obama abbia deciso di rilasciare una dichiarazione per rassicurare gli americani non sull’occupazione, il lavoro o la sanità bensì sulla presunta minaccia extraterrestre. Beh, diciamo che è stata costretta: da settembre, infatti, sul sito della residenza ufficiale del Presidente degli Stati Uniti esiste una sezione chiamata We the People creata per dare voce agli elettori. Ogni cittadino americano può pubblicare un petizione cui i politici sono costretti a rispondere nel caso raccolga un numero sufficiente di firme.
Ebbene, come leggiamo sul Washington Post, più di 5mila persone hanno firmato una petizione per chiedere alla Casa Bianca di rivelare tutto ciò che il Governo sa sugli extraterrestri. Inoltre, più di 12mila elettori hanno inoltrato una seconda richiesta reclamando tutta la verità sul reclutamento di esseri umani da parte degli alieni. La risposta è stata secca: non c’è alcuna evidenza a favore dell’esistenza di vita al di fuori del nostro pianeta, del tentativo da parte di alieni di contattare o reclutare membri della razza umana, di un disegno politico mirato a nascondere la verità alle persone.
Non per questo, tuttavia, gli sforzi per cercare gli extraterrestri si interrompono. Gli Stati Uniti continuano a monitorare lo Spazio alla ricerca di vita aliena impegnando fondi ed energie: prendiamo il Search for Extraterrestrial Intelligence (Seti), che utilizza telescopi terrestri per cercare di captare messaggi da altri mondi; o il satellite Nasa Kepler, che orbita intorno alla Terra alla ricerca di pianeti con condizioni tali da permettere la vita; o infine il Mars Science Laboratory, un veicolo simile a un’automobile creato dalla Nasa per esplorare il suolo marziano alla ricerca di molecole biologiche.
Se i più paurosi si saranno sentiti sollevati dalle dichiarazione della Casa Bianca, i fan di Et sono delusi e un po’ arrabbiati. Dove sono finiti, si chiedono, i documenti governativi in cui si racconta degli incontri tra militari e piloti di linea con Ufo? Le domande a cui rispondere sono ancora così tante che si parla di nuove petizioni. Steven Bassett, il primo firmatario della petizione da 5mila firme, ha annunciato sul sito del suo Paradigm Research Group che ha intenzione di inoltrare alla White House una nuova richiesta. “ La risposta che abbiamo ricevuto è inaccettabile.
Abbiamo bisogno di maggiori spiegazioni. Ecco perchè il Paradigm Research Group si farà promotore di una nuova petizione per chiedere al governo di rivelare tutto quel che sa sugli alieni ”, ha scritto Bassett.
La Casa Bianca, dal canto suo, non si scompone. “ Non c’è motivo per cui qualcuno non possa sottoscrivere una seconda petizione - ha riferito all’ Huffington Post Matt Lehrich, il portavoce della Casa Bianca – se raccoglierà il numero di firme stabilito, allora avrà una risposta. Certo, se la domanda è sempre la stessa, lo sarà anche la risposta”. Il Governo tiene tutto sotto controllo, anche se bisogna dire che ha alzato la soglia di firme necessarie per considerare una petizione valida: dalle 5mila di inizio settembre alle 25mila attuali. Si sarà stancata di rispondere a domande scomode? Non è la prima volta, infatti, che la Casa Bianca si trova in impaccio: solo per fare alcuni esempi, oltre 100 mila persone hanno già chiesto la legalizzazione della marjuana e molti pressano per la legalizzazione dei matrimoni gay.
Odorizantele de camera au un miros placut, dar pot cauza probleme serioase, afirma autorii unui nou studiu prezentat în cadrul Colegiului American pentru Alergii, Astm si Imunologie. Produsele pentru parfumarea camerei contin adesea compusi organici volatili (COV), care includ substante chimice precum formaldehida, derivati de petrol, limonen, esteri si alcool.
Expunerea la COV, chiar si la un nivel acceptat ca fiind sigur pentru sanatate, poate creste riscul aparitiei astmului bronsic la copii si produce iritarea ochilor si a tractului respirator, dureri de cap si ameteli.
Din acest motiv, specialistii spun ca problema odorizantelor de camera este mai grava decât ne imaginam. Aproximativ 20% din populatie si 34% dintre persoanele care sufera de astm bronsic au probleme de sanatate din cauza acestor parfumuri, care au tendinta de a declansa unele alergii sau de a le înrautati pe cele existente.
Chiar si în ceea ce priveste odorizantele compuse din produse "naturale", specialistii spun ca nici acestea nu sunt inofensive, având în vedere ca sunt destul de puternice pentru a putea acoperi mirosurile neplacute.
Din acest motiv, doctorii recomanda sa renuntam la odorizantele de camera si sa recurgem la metoda traditionala de îndepartare a mirosurilor neplacute, si anume la aerisirea prin deschiderea geamului.
On February 6th 2012, The Zeitgeist Movement Israel will host a Global Awareness Event in Tel Aviv, Israel in the context of Human Sustainability and World Peace.
On the heels of what appears to be an accelerating intent for military intervention in Iran from the United States and it allies, along with the world's major powers rapidly increasing armament developments in the midst of growing social destabilization, resource depletion and economic breakdown, The Zeitgeist Movement, a worldwide sustainability advocacy group working without borders or countries will be conducting a conference on the increasingly important issues of global cooperation and the means to obtain peace and human prosperity for the long term.
A feature of the event will be a lecture conducted by Peter Joseph, founder of The Zeitgeist Movement, entitled "Defining Peace". This talk will examine the historical roots of war; its technical irrelevancy; the State's historical psychological coercion of mass appeal; the inherent exclusive benefits to the upper class and denigration of the lower class; the broad inefficiency of the State itself as a diversionary/business entity and its inherent conflict propensity; along with how the only way of achieving lasting human peace is through the dissolving of the Market System catalysts, the Ownership Class and the State entity itself.
About: The Zeitgeist Movement is a global sustainability activist group working to bring the world together for the common goal of species sustainability before it is too late. It is a social movement, not a political one, with over 1100 chapters across nearly all countries. Divisive notions such as nations, governments, races, political parties, religions, creeds or class are non-operational distinctions in the view of The Movement. Rather, we recognize the world as one system and the human species as a singular unit, sharing a common habitat. Our overarching intent could be summarized as “the application of the scientific method for social concern.”
“This is a novel application of existing materials, and has potential for rapid, high-volume manufacturing processes or packaging applications,” says Dr. Michael Dickey, an assistant professor of chemical and biomolecular engineering at NC State and co-author of a paper describing the research.
The process is remarkably simple. Researchers take a pre-stressed plastic sheet and run it through a conventional inkjet printer to print bold black lines on the material. The material is then cut into a desired pattern and placed under an infrared light, such as a heat lamp.
The bold black lines absorb more energy than the rest of the material, causing the plastic to contract – creating a hinge that folds the sheets into 3-D shapes. This technique can be used to create a variety of objects, such as cubes or pyramids, without ever having to physically touch the material. The technique is compatible with commercial printing techniques, such as screen printing, roll-to-roll printing, and inkjet printing, that are inexpensive and high-throughput but inherently 2-D.
By varying the width of the black lines, or hinges, researchers are able to change how far each hinge folds. For example, they can create a hinge that folds 90 degrees for a cube, or a hinge that folds 120 degrees for a pyramid. The wider the hinge, the further it folds. Wider hinges also fold faster, because there is more surface area to absorb energy.
“You can also pattern the lines on either side of the material,” Dickey says, “which causes the hinges to fold in different directions. This allows you to create more complex structures.”
The researchers developed a computer-based model to explain how the process works. There were two key findings. First, the surface temperature of the hinge must exceed the glass transition temperature of the material, which is the point at which the material begins to soften. Second, the heat has to be localized to the hinge in order to have fast and effective folding. If all of the material is heated to the glass transition temperature, no folding will occur.
“This finding stems from work we were doing on shape memory polymers, in part to satisfy our own curiosity. As it turns out, it works incredibly well,” Dickey says.
Sono cinque milioni i twit passati al setaccio ogni giorno in un palazzo dell’ intelligence americana, in un luogo senza coordinate (note) della Virginia. Insieme ci sono anche i post pubblicati su Facebook, i titoli dei giornali e tutto quello che circola liberamente sul Web, spulciati dai “bibliotecari della vendetta”, come sono stati soprannominati gli addetti dell’ Open Source Center della Cia. Lo scopo? Scoprire che tempo fa in terra straniera, sondare gli umori, e magari cercare di intercettare in anticipo malcontenti e rivoluzioni, dopo quelli che hanno scosso il mondo arabo. A svelare le attività di veggenti dell’intelligence americana attraverso i social media è Associated Press, che è entrata nell’Open Source Center e secondo la quale nella palla di vetro della Cia ci sarebbero paesi come la Cina, il Pakistan e l’ Egitto.
“Dall’arabico al mandarino, da un twit arrabbiato a un blog riflessivo, gli analisti reperiscono informazioni, spesso nella loro lingua nativa”, spiega Ap: “Poi (gli analisti, ndr) li confrontano con i giornali locali o con una conversazione al telefono intercettata clandestinamente. A partire da questo poi costruiscono un’istantanea voluta dai più alti livelli della Casa Bianca, dando per esempio un’occhiata in tempo reale all’umore di una regione subito dopo l’attacco dei Navy Seals che ha ucciso Osama bin Laden o forse elaborando una previsione di quale paese del Medio Oriente è sul punto di scoppiare in rivolta”.
Nata come misura antiterrorismo post 11 settembre, l’ Open Source Center si dedica al mondo dei social media soprattutto dallo scoppio della Rivoluzione Verde in Iran nel 2009 (dopo l’elezione di Mahmoud Ahmadinejad) . Gli uffici del centro si trovano in Virginia, in un luogo protetto dal segreto (in un “anonima zona industriale”), ma vanta sicuramente diverse filiali sparse nel mondo, nelle ambasciate statunitensi, in modo da trovarsi più vicino ai luoghi tenuti sott’occhio. A lavorarci hacker alla Lisbeth Salander (la protagonista della saga Millennium di Stieg Larsson) possibilmente multilingue, “che sanno come trovare cose che altre persone non sanno neanche esistere”, spiega Doug Naquin, direttore del centro di intelligence.
Un esempio dell’attività dell’Open Source Center è quella che ha seguito l’uccisione di Bin Laden a maggio, in Pakistan. Registrando l’origine linguistica dei twit (non limitandosi quindi a mapparne l’origine geografica) l’Open Source Center ha osservato che la maggior parte dei cinguettii lasciati sul Web erano in urdu (dal Pakistan) e cinese. L’ umore degli utenti? Per lo più negativo, come forse c’era da attendersi. Infatti il raid, visto da Twitter, è stato percepito come una sorta di affronto alla sovranità del Pakistan.
Acesta utilizeaza un senzor de distanta si imagine dezvoltat de Microsoft pentru Kinect (un dispozitiv periferic, care le permite utilizatorilor sa se foloseasca de consola Xbox 360 fara ajutorul unui controller fizic, ci doar folosind gesturi ale corpului si comenzi vocale).
Pe suprafete plate, robotul se deplaseaza rapid cu ajutorul unor roti, iar pe teren accidentat acesta poate pasi, având membre articulate. De aseamenea, "labele" câinelui robot sunt dotate cu senzori, asemanatori celor de parcare, pentru a evita obstacolele.
Câinele functioneaza prin pre-programarea software-ului dar si prin apasarea pe mânere. În plus, acesta raspunde la instructiunile utilizatorului, iar o voce computerizata îl anunta pe acesta în ce directie merge. Specialistii spun ca versiunea urmatoare a câinelui robot va include comanda vocala si GPS pentru o mai buna acuratete a comenzilor.
Aparatul este înca în stadiul de cercetare si dezvoltare, dar producatorii spun ca el are potentialul de a înlocui în viitorul apropiat câinii însotitori ai nevazatorilor, mai ales în contextul în care populatia globala îmbatrâneste într-un ritm alert.
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