Ministrul Educatiei, Daniel Funeriu, îi invită pe presedintii partidelor de opozitie la o discutie serioasă despre viitorul educatiei din România, pe baza Legii educatiei, după ce a fost anuntată promovabilitatea de 44,47 la sută la bacalaureat, înainte de contestatii.
"Miza, astăzi, doamnelor si domnilor, este România. Acestă miză este mai mare decât ar putea fi interesele vreunui partid si de aceea invit presedintii partidelor de opozitie la o discutie serioasă despre viitorul educatiei din România", a declarat, luni, ministrul Educatiei, în prima declaratie de presă făcută după anuntarea rezultatelor la examenul de bacalaureat înaintea contestatiilor.
Vezi rezultatele la Bacalaureat 2011 pentru toata tara. ("Generatia ratatilor" dupa cum subtitreaza bzi.ro)
Ministrul Daniel Funeriu a adăugat că toti cei care se întreabă de ce avem nevoie de o nouă lege a educatiei stabilă au primit un răspuns clar duminică, după anuntarea rezultatelor la bacalaureat.
Funeriu a spus că rezultatele examenului de bacalaureat din acest an arată clar că România este la răscruce.
"Aceste rezultate si comportamentele pe care le-au generat sunt exact oglinda societătii noastre de azi. Natiunea noastră trebuie să aleagă dacă merge pe mâna celor onesti, muncitori, perseverenti sau dacă vrem să încurajăm în continuare smecheria, nemunca, superficialitatea si eludarea lucrurilor", a declarat Funeriu.
El a precizat că optiunea echipei sale este a celor care vor să schimbe România.
"Suntem în echipa celor care doresc o Românie fără complexe, o România sigură pe ea, o Românie care îsi ia destinul în propriile ei mâini. Suntem de partea celor care vor o Românie cu fruntea sus, si nu o Românie cu mâna întinsă, suntem de partea celor care vor o Românie voluntară, si nu o României a văicărelilor si a sanselor ratate", a spus Funeriu.
Ministrul Educatiei a mai spus că cei care nu au reusit acum la examenul de bacalaureat vor avea posibilitatea să participe la sesiunea din toamnă, dar a atentionat că exigenta va fi la fel de mare.
"Nu mă astept la nicio scădere a standardelor nici cu ocazia solutionărilor eventualelor contestatii, nici la examenul din toamnă si la niciun examen de bacalaureat de acum încolo. Ar fi o greseală capitală din partea cuiva să îsi imagineze că am dat vreun pas înapoi. Vreau să le spun celor care astăzi nu se află printre cei cu succes că mâine, cu conditia muncii, seriozitătii si perseverentei, vor putea si ei să obtină diploma de bacalaureat", a adăugat Funeriu.
Se spune ca alcoolismul a facut mai multe victime decat ciuma si razboiul la un loc, el reprezentand una dintre cele mai mari suferinte ale omenirii. Spre deosebire de alte maladii, în care bolnavul sufera el singur, alcoolismul cronic face numeroase victime în familie, lovind în destinul nevinovat al celor apropiati.
„Placere” de sinucigas
Pana nu de mult, alcoolismul era considerat un viciu, o „placere nevinovata”, si mai mult sau mai putin interzisa, deoarece, în formele lui cronice, agravante, ridica probleme severe privind integritatea morala si sociala a celui afectat. In ultimul timp, însa, este acceptata ideea de boala, o data cu definitivarea concluziilor despre consecintele dezastruoase ale consumului de alcool, atat asupra individului însusi cat si asupra descendentilor directi (copiii), a climatului familial, a criminalitatii, a accidentelor de munca si rutiere sau a sinuciderilor.
Iata cateva dintre dezastrele pe care le produce alcoolismul asupra organismului: * atrofierea testiculelor sau a ovarelor; * actiune degenerativa asupra descendentilor, ce se vor naste cu grave anomalii; * afectiuni ale aparatului cardiovascular; * leziuni renale; * ciroze hepatice; * maladii ale stomacului; * degenerescenta progresiva a sistemului nervos central si periferic, care conduce la alterarea comportamentului: impulsivitate, iritabilitate, agresivitate, violenta, apatie, somnolenta, tulburari de atentie, de gandire, de vointa. Intr-un cuvant, degradarea totala a personalitatii.
De la euforie, la prabusire
A consuma bautura înseamna a fi alcoolic? Raspunsul nostru este „nu”. Veselia euforica data de consumarea moderata a unui pahar de bautura, chiar zilnic, nu se confunda cu betia. Sintagma „beat-mort”, exprima cel mai plastic starea de intoxicare profunda a organismului. Uneori ea conduce la deces, fapt frecvent în sezonul rece, cand alcoolicii se prabusesc din cauza vasodilatatiei paralitice, determinata de alcool. Betia, deci, se manifesta printr-o succesiune de stari în care dezorganizarea personalitatii se accentueaza progresiv, trecand de la o perioada de excitatie si buna-dispozitie initiala, la o etapa depresiv hipnotica.
Se cunosc, din pacate, cazuri de betie agresiva, cand se distrug mobila, vesela, lucrurile uzuale, cand se produc incendieri. Viata sufleteasca a bolnavului – caci în aceste situatii alcoolicul este un bolnav iresponsabil – se reduce la o furie animalica, distructiva. Atunci au loc grave mutilari fizice si sufletesti, carora le cad prada cei din jur: sotia (cel mai frecvent), copiii, rudele apropiate. Nici cuvantul, nici mangaierea ori amenintarea nu mai au vreun efect pozitiv, deoarece constiinta alcoolicului în plina betie este anihilata aproape total.
Remediul se afla chiar in bolnav
Exista si betii halucinante sau delirante, ceea ce a condus la concluzia ca alcoolismul cronic reprezinta cea mai primejdioasa boala mintala. Statisticile omenirii privind decesele, ranirile grave, mutilarile, sinuciderile, accidentele rutiere, sunt atat de relevante, încat, în ultimele decenii, aceasta afectiune a intrat sub jurisdictia unor organe de protectie.
Ce se poate face? Este de la sine înteles ca familia alcoolicului cronic este una cu probleme. Fiind o deprindere care îsi are radacini deopotriva în viata sufleteasca si în organismul bolnavului, alcoolismul nu poate fi tratat cu cateva pilule strecurate de familie în mancare sau în bautura. Un tratament cu bune rezultate va cere din partea bolnavului o participare activa si un efort personal; într-un cuvant, o straduinta de regenerare morala, fizica si psihica, asociata cu cura de dezalcoolizare.
Dezobisnuirea de alcool constituie un act de vointa, o victorie asupra propriilor slabiciuni. Acest fapt înseamna un timp îndelungat, pentru ca cel ce s-a impregnat cu alcool timp de 10-15 ani, ajungand la o alterare a organismului, nu se poate vindeca miraculos. Terenul acestei discutii fiind, astfel, eliberat de prejudecati sau de credinta naiva în leacuri imediate si miraculoase, se ridica urmatoarele întrebari. Se poate vindeca definitiv alcoolismul cronic? Ce anume determina esecurile tratamentului, recidivele, dat fiind ca sunt frecvente cazurile la bolnavi care au urmat mai multe cure de dezintoxicare?
Iata ce se poate raspunde: * cand alcoolismul este o consecinta a unei boli mintale, psihoze, socuri sau descendenta familiala, ameliorarile sunt putin probabile; * cand e cauzat de deprinderi rele, de influenta anturajului, de imitarea „modelului”, de activitatea profesionala (ospatari, distilatori), prognosticul este optimist; * cand membrii familiei alcoolicului au o structura a personalitatii puternica si echilibrata, sansele de a schimba orientarea sufleteasca a acestuia sunt mai mari; * tratamentul de dezalcoolizare este mai eficient atunci cand se asociaza unui tratament corporal, care-si propune inlaturarea consecintelor organice ale impregnatiei cu fatidicul drog. Drog de care, din pacate, poate beneficia orice individ si in cantitati nelimitate!
Italy is again at a crossroads about freedom and quality of its media. On July 6, Italy's telecommunication regulator, AGCOM, will decide how long will let the public debate about the new enforcement tools to fight copyright infringement the Agency is introducing. The law, introduced by the present government, generally requires AGCOM to adopt anti-piracy tools, but the AGCOM proposal gives the Authority itself the power to remove content from Italian websites or to block access to foreign websites accused by copyright holders to break their rights. There will be no need to go through a regular trial, no judge will be involved in the decision making. Accused sites will have only 5 days to explain their position and their right to defend themselves will be quite limited.
The issue has generated very polarized reactions.
Strong approvers have been some publishers associations such as TV producers (APT), film (ANICA), music (FIMI). But they limit their support to new rules that are able to suppress only those sites that do business selling intellectual property that they don't own, while explicitly excluding from the desired effects of the new regulations all private blogs, sites, platforms, search engines and other operators whose business is not piracy.
Critics include groups like Agora Digitale and Altroconsumo, personalities such as Stefano Rodotà - former European data protection commissioner and very respected jurist - and scholars such as Juan Carlos De Martin - one of Nexa founders and fellow at Harvard's Berkman Center - and many others. They think that the AGCOM proposal is worded in a way that enables the Authority to shut down any site, including those that are not in the piracy business and are focused on gathering and analysing the news, without granting a real right to defense.
In many past cases, copyright trials have shown different controversial interpretations about, for example, the freedom of the press and the fair use of some copyrighted content. For sure, copyright is not always a matter that can be decided through simple administrative solutions. Without recourse to the courts in these matters, unilateral decisions are likely.
In a country that has allowed some of the weirdest irregularities in the media system for a western democracy, with a Prime Minister personally owning three of the seven major national television networks and controlling the three public networks through his political power, the regulation of the internet seems to be a fundamental subject for any local democratic development. The Economist has covered some of the consequences, while showing how television was used by the government to silence the issues at stake in the recent referendums. As a matter of fact, the government has lost those referendums and many experts considered this setback as a victory for new social media and the internet.
There are not many news about this subject in English. Who reads Italian can take a look at Juan Carlos De Martin piece published by la Stampa. AGCOM's head Calabrò's answer. And many other links at the end of previous posts. Vocal opposition to the AGCOM decision is growing on the Italian network: LatoSinistro, EsserePrimisuGoogle, IsolaCassintegrati, ValigiaBlu, DoppioCieco, MatteoPlatone, Ciwati, LucaNicotra, YesPolitica, Semioblog, Gilioli, Nichilista, DamianoZito, Avaaz, MinimaAcademica, PiccoloSocrate, Ilmiopaesealtrove, Pozzallo, Pasteris, Perdukistan, GuidoVetere. And many more...
FIMI (association of music publishers) has circulated a mail about Obama's administration support to AGCOM, quoting this Us document: "The United States encourages Italy to ensure that the AGCOM regulations are swiftly promulgated and implemented, that these regulations create an effective mechanism against copyright piracy over the Internet, and that they address all types of piracy that takes place online."
Source: blog.debiase.com - Author: Luca De Biase (An Italian journalist writes about perspective, a notion that Italy sort of invented and then forgot. Because the future is the consequence of what we do today. Subjects: knowledge economy and happiness, social media and information ecology, value and vision.)
L’intera volta celeste immortalata a 360° in un’unica gigantesca immagine: è lo straordinario risultato ottenuto da Nick Risinger, un giovane astronomo dilettante americano, che qualche giorno fa ha pubblicato online la prima superimmagine a tutto cielo della Via Lattea come appare dal nostro pianeta. È una enorme fotografia panoramica, navigabile e interattiva, da 5.000 megapixel nella quale sono ritratti gli oltre 20.000.0000 di stelle visibili dai due emisferi della Terra.
Passione hi tech
Per realizzala Risinger, accompagnato dal papà, ha viaggiato per oltre 96.000 km in tutti e 5 i continenti e si è servito dalle più moderne tecnologie. Per essere certo di non dimenticare nemmeno un angolo di cielo, ha diviso la volta celeste in 624 aree uniformi e ha inserito le loro coordinate nel suo portatile. Ogni area è stata immortalata con 60 scatti da una batteria di 6 fotocamere montate su uno speciale cavalletto motorizzato controllato da un GPS e sicrnonizzato con il movimento degli astri. Per ottenere il miglior risultato possibile Nick ha lavorato solo nelle notti più buie, quelle di luna nuova, quando il cielo era sereno e in luoghi non raggiunti dall’inquinamento luminoso.
Superpuzzle
Al termine del suo giro del mondo Risinger è tornato a casa con 37.440 immagini che ha assemblato utilizzando speciali programmi per l’editing delle fotografie astronomiche. Sul suo sito, che in pochi giorni ha raggiunto qualche milione di contatti, potete letteralmente immergervi nella sua superfotografia e vedere stelle e costellazioni invisibili dal nostro emisfero. E se apprezzate l’opera del giovane astronomo potete cliccare sul pulsante “Donate” e contribuire alle spese, sicuramente non trascurabili, che ha sostenuto.
Given sufficient forward speed, a bicycle pushed sideways, will not fall over. Scientists have been trying to find a conclusive explanation for this remarkable characteristic for over a century. This week, researchers at TU Delft have thrown new light on the question in a publication in Science.
Staying stable
The research at TU Delft, in collaboration with scientists from Cornell University (USA), centred on the following intriguing question: why is a bicycle self stable, above a certain speed? You add speed to a bike and can then give it a sideways push without it falling over.
Rotating wheels
Scientists have long been poring over this complicated question, even from as far back as the nineteenth century. Until recently, the consensus within the scientific community was that the stability was very closely related to two factors. First, the rotating wheels of the bicycle were supposed to provide stability through gyroscopic effects. Secondly, it was thought that the ‘trail’ played an important part. Trail is the distance by which the contact point of the front wheel trails behind the steering axis.
Predicting
The publication by TU Delft in Science puts paid to this old notion once and for all. 'We have known for years that the generally accepted explanation for the stability of the bicycle was too simple,' says researcher Dr Arend Schwab of the 3mE faculty at TU Delft. 'Gyroscopic effects and trail do help, but are not essential for stability.' Dr Schwab and a number of colleagues brought out a publication several years ago on the theory behind the stability of the bicycle (in 2007 in Proceedings of the Royal Society, doi:10.1098/rspa.2007.1857). A mathematical model with around 25 physical parameters was developed at the time, which appeared to be able to predict very accurately whether, and at what speeds, a particular design of bicycle would be stable.
The Experiment
'In our publication in Science we have now shown not only theoretically but also by means of experiment that our insights are correct.' Together with PhD student Jodi Kooijman, Schwab designed and constructed a bicycle with which it could be shown, in an experiment, that both gyroscopic effects and trail are not necessary for a bicycle to remain stable by itself above a certain speed. This is the so-called Two Mass Skate bicycle. It has small and counter rotating wheels, which means there is no gyroscopic effect to speak of, and a small negative trail (in other words, where the point of contact of the front wheel is marginally in front of the steering axis). And yet the bicycle remains stable.
'It was not easy,' explains PhD student Jodi Kooijman, who carried out most of the experimental work. 'The first prototype did not work, and we had almost given up hope after a number of iteration attempts, when we suddenly found ourselves able to show the stability. But of course everything has to fall into place. You have to deal with the ground surface, for example, which has to have exactly the right roughness and stiffness. In Sporthal II of TU Delft we found all the right conditions.'
Steering
So the theory has now been proven by experiment. But has the experimental work led to the emergence of new theoretical insights? Dr Schwab answers, 'We have demonstrated that the mass distribution is also important for stability, especially the location of the centre of mass of the bicycle's steering mechanism.' For a bicycle to be stable, the steering mechanism has to be unstable; if the bike falls, the steering should fall even more quickly.
Bicycle manufacturers
Are the theoretical insights of Schwab and his companions of any use to bicycle manufacturers? 'Certainly. Today’s bicycles are the result of a fairly long evolutionary process, and are therefore rather conservative. Essentially, there is nothing about the basic design of the bicycle that has changed since the end of the nineteenth century. Manufacturers can use our model to make directed modifications to the stability of their bicycles. That may be of particular interest for unusual designs, such as recumbent bicycles, folding bicycles and cargo bicycles.'
Title: A Bicycle Can Be Self-Stable Without Gyroscopic or Caster Effects.
Authors: J.D.G. Kooijman; A. L. Schwab (TU Delft), J.P. Meijaard (University of Twente), J.M. Papadopoulos (University of Wisconsin–Stout), A. Ruina (Cornell University)
Fiu al unui sef de trib din Africa de Sud, originar din provincia Transkei, Nelson Rolihlahla Mandela s-a nascut la 18 iulie 1918 si a fost crescut dupa moartea tatalui sau de un unchi, sef al tribului Tembu. Educat in spiritul dreptatii si respectarii traditiei, Nelson a visat inca de mic sa fie conducatorul care va elibera poporul sau de sub dominatia odiosului regim de apartheid. Absolvent al scolii superioare metodiste din Healdtown, Mandela s-a inscris apoi la Fort Hare College, dar a fost exmatriculat pentru ca organizare o actiune de boicotare a orelor de curs.
In 1940, s-a mutat la Johannesburg, unde a absolvit facultatea la fara frecventa, dedicindu-se Dreptului. In 1944, s-a inscris in organizatia de tineret a Congresului National African (CNA), devenind in scurt timp unul dintre liderii acesteia. In perioada post-belica, actiunile sale de nesupunere civica, inspirata de modelul lui Mahatma Gandhi, ii vor aduce mai multe condamnari la inchisoare. Tot mai cunoscut in rindul militantilor anti-apartheid si considerat cel mai periculos activist al CNA de catre regimul de la Pretoria. Pe 12 iunie 1964, el va fi condamnat la inchisoare pe viata, ispasind o mare parte din pedeapsa in temuta inchisoare Robben Island.
De aici, in 1984 va fi mutat la inchisoarea Pollsmoor, din Capetown iar in decembrie 1988 la inchisoarea Victor Verster, loc de unde va fi eliberat, in 1990. De-a lungul celor 27 de ani de detentie, Mandela a primit numeroase oferte din partea guvernului de a fi eliberat, cu conditia sa inceteze lupta sa pentru dreptate si egalitate sociala, dar le-a refuzat. Dupa eliberare, a continuat sa pledeze pentru drepturile populatiei de culoare. In 1993, a fost laureat al Premiului Nobel pentru Pace iar in 1994 a devenit primul presedinte de culoare al Africii de Sud. S-a retras din viata politica in 1999, ducand in prezent o existenta modesta, in satul sau natal din Transkei.
La missione STS-134 dello Space Shuttle, la penultima nella storia della gloriosa navetta spaziale americana, per l'Italia ha un significato particolare. Non solo perché con l'Endeavour parte il nostro Roberto Vittori, che a bordo della Stazione Spaziale Internazionale si unirà per un paio di settimane a Paolo Nespoli, in orbita dallo scorso dicembre; facendo sì che l'Italia diventi l'unico Paese, Usa e Russia a parte, che abbia avuto due propri rappresentanti contemporaneamente a bordo della Iss. Ma anche perché con Vittori partono molti esperimenti italiani di grande valore scientifico. Spicca su tutti AMS 2 (Alpha Magnetic Spectrometer 2), un vero "cacciatore di antimateria". "Di fatto non conosciamo la composizione del 95% dell'Universo", spiega Roberto Battiston, docente dell'Università di Perugia e presidente della commissione nazionale per la fisica astroparticellare dell'Istituto nazionale di fisica nucleare, uno dei padri di AMS 2. "Questo esperimento speriamo appunto che ci porti risposte sulla materia "altra", cioè quella che non si vede con i normali mezzi di rilevazione. Ma che si trova anche nella stanza in cui siamo, ed è sei volte più abbondante di quella che vediamo" aggiunge Battiston.
L'AMS 2 è un vero colosso, grande quanto una stanza di cinque metri per quattro. In sostanza si tratta di un complesso sistema di rivelatori per lo studio dei raggi cosmici, la radiazione che proviene dallo spazio composta da particelle (protoni ed elettroni), nuclei atomici e una piccola parte di antiparticelle elementari. "Le antiparticelle più semplici, positroni e antiprotoni, sono state osservate e sono perfino utilizzate, pensiamo alla Pet, la tomografia a emissione di positroni, che sono elettroni positivi" sottolinea Battiston. "Riuscire però a rivelare per la prima volta un antinucleo di elio o di carbonio sarebbe fondamentale per capire l'universo primordiale".
AMS 2 registrerà il passaggio di decine di miliardi di raggi cosmici prima che si scompongano o si annichiliscano nell'interazione con l'atmosfera del nostro pianeta. L'esperimento è realizzato dall'Istituto nazionale di fisica nucleare in collaborazione con l'Asi (Agenzia spaziale italiana). Il nostro Paese è il primo "contributor", avendo coperto circa il 25% del costo del progetto, valutabile complessivamente in circa 1,5 miliardi di euro.
Working with funding from Google, they hope to make computers understand what it’s like to pursue an outcome only to be disappointed. That, they think, could really help computers predict the future.
While software may never know what it’s like to roll out of bed with splitting headache and dress quietly in the dark, it can certainly measure the distance between a desired outcome and the actual outcome achieved. And by doing so computers could learn to minimize “regret,” which in this case is measured by that distance.
TAU computer scientists working on learning theory and other thorny computer intelligence issues think that by teaching computers to reduce regret, they would essentially be teaching them to evaluate all the relevant variables surrounding an outcome in advance. This would allow them to do things like more efficiently route Internet traffic, prioritize server resource requests, or predict when traffic to a site might spike and provide the necessary capacity beforehand. And they could do it all based on data coming to them in real-time.
RECORDED STREAM of Assange, iek & Goodman Conversation July 2, 11am EDT.
Stainless Steel Rat, is the play about the life and works of Julian Assange a rip-off?
Paul Tomlinson writes in theHarry Harrison Official News Blog:Assange is known for taking things which dont belong to him and making them freely available. The authors of the wikiplay Stainless Steel Rat seem to have taken a similar approach, but theyre using Harry Harrisons creations for their own profit. Shame.
On the words of Harry Harrison:These guys are ripoff artists. I'd have them in jail if I could. I'm trying.
Meanwhile, in theSydney Morning Herald:Stainless Steel Rat attempts to answer all [big] questions [about Assange], while offering chuckles and cheap laughs along the way. The result is a half-digested dog's breakfast of political thriller, media satire, sex comedy and speculative psycho-sexual analysis. The play's references to sodomy border on the obsessive. Drawing parallels between Assange's penetration of network firewalls, to his bare-backing of Swedish groupies, is plain misguided. [...] A gutsy attempt to grab a headline and run with it, but as it stands, Elisha's framing is clumsy - unnecessary, really - and his desire to titillate will strike anyone, with more than a passing interest in the subject, as patronising or dismissive.
Bradley Manning Rally in New York!
Elaine Brower invites us fromBradley Manning dot org:Get Your I am Bradley Manning picture taken in Union Square at the Bradley Manning Photo Booth. Saturday, July 2 from 2-5 pm. Check out your photo and then talk to other people about Brads case and encourage them to support his cause! If everyone who reads this announcement talked to 10 people about Brad Manning and why he should be free, we could made a big dent in that 40% of New Yorkers who never heard of him! So come out and show your support, and lets get the word out on this holiday weekend.
Legal Complaint against Visa & MasterCard
WikiLeaks tweeted theLegal Complaint against Visa & MasterCard for political censorship; Forbes dot com presents asummary by Andy Greenberg:The complaint argues that the three payment firms have violated Articles 101 and 102 of the E.U. Treaty, which deal with competition among businesses and forbid the creation of anti-competitive cartels. Article 101 prevents firms from creating partnerships for the purposes of price fixing, and Article 102 forbids firms in a dominant position from abusing that position. Both Visa and MasterCard have claimed that payments to WikiLeaks and DataCell were suspended because they potentially violate the companies terms of service. MasterCard has gone as far explaining that it prohibits customers from directly or indirectly engaging in or facilitating any action that is illegal. Visa has stated that it is investigating the nature of [WikiLeaks] business and whether it contravenes Visa operating rules.
Today, at 11 am EDT, Amy Goodman To Host Discussion With WikiLeaks Editor-In-Chief Julian Assange and Slovenian Philosopher Slavoj iek
Democracy Now anchor Amy Goodman will host a Discussion With WikiLeaks Editor-In-Chief Julian Assange and Slovenian Philosopher Slavoj iek at 11 am EDT. Full informationhere.
Simultaneously (at 11am EST; 4pm GMT; 8pm AEST), Frontline Club will host a special"in conversation" eventabout this same Democracy Now broadcasting, according to their Twitter account.
By directly linking the motions of two physically separated atoms, the technique has the potential to simplify information processing in future quantum computers and simulations.
Described in a paper published Feb. 23 by Nature, the NIST experiments enticed two beryllium ions (electrically charged atoms) to take turns vibrating in an electromagnetic trap, exchanging units of energy, or quanta, that are a hallmark of quantum mechanics. As little as one quantum was traded back and forth in these exchanges, signifying that the ions are "coupled" or linked together. These ions also behave like objects in the larger, everyday world in that they are "harmonic oscillators" similar to pendulums and tuning forks, making repetitive, back-and-forth motions.
"First one ion is jiggling a little and the other is not moving at all; then the jiggling motion switches to the other ion. The smallest amount of energy you could possibly see is moving between the ions," explains first author Kenton Brown, a NIST post-doctoral researcher. "We can also tune the coupling, which affects how fast they exchange energy and to what degree. We can turn the interaction on and off."
The experiments were made possible by a novel, one-layer ion trap cooled to minus 269 C (minus 452 F) with a liquid helium bath. The ions, 40 micrometers apart, float above the surface of the trap. In contrast to a conventional two-layer trap, the surface trap features smaller electrodes and can position ions closer together, enabling stronger coupling. Chilling to cryogenic temperatures suppresses unwanted heat that can distort ion behavior.
The energy swapping demonstrations begin by cooling both ions with a laser to slow their motion. Then one ion is cooled further to a motionless state with two opposing ultraviolet laser beams. Next the coupling interaction is turned on by tuning the voltages of the trap electrodes. In separate experiments reported in Nature, NIST researchers measured the ions swapping energy at levels of several quanta every 155 microseconds and at the single quantum level somewhat less frequently, every 218 microseconds. Theoretically, the ions could swap energy indefinitely until the process is disrupted by heating. NIST scientists observed two round-trip exchanges at the single quantum level.
To detect and measure the ions' activity, NIST scientists apply an oscillating pulse to the trap at different frequencies while illuminating both ions with an ultraviolet laser and analyzing the scattered light. Each ion has its own characteristic vibration frequency; when excited, the motion reduces the amount of laser light absorbed. Dimming of the scattered light tells scientists an ion is vibrating at a particular pulse frequency.
To turn on the coupling interaction, scientists use electrode voltages to tune the frequencies of the two ions, nudging them closer together. The coupling is strongest when the frequencies are closest. The motions become linked due to the electrostatic interactions of the positively charged ions, which tend to repel each other. Coupling associates each ion with both characteristic frequencies.
The new experiments are similar to the same NIST research group's 2009 demonstration of entanglement -- a quantum phenomenon linking properties of separated particles -- in a mechanical system of two separated pairs of vibrating ions. However, the new experiments coupled the oscillators' motions more directly than before and, therefore, may simplify information processing. In this case the researchers observed quantum behavior but did not verify entanglement.
The new technique could be useful in a future quantum computer, which would use quantum systems such as ions to solve problems that are intractable today. For example, quantum computers could break today's most widely used data encryption codes. Direct coupling of ions in separate locations could simplify logic operations and help correct processing errors. The technique is also a feature of proposals for quantum simulations, which may help explain the mechanisms of complex quantum systems such as high-temperature superconductors.
In addition, the demonstration also suggests that similar interactions could be used to connect different types of quantum systems, such as a trapped ion and a particle of light (photon), to transfer information in a future quantum network. For example, a trapped ion could act as a "quantum transformer" between a superconducting quantum bit (qubit) and a qubit made of photons.
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Se spune ca alcoolismul a facut mai multe victime decat ciuma si razboiul la un loc, el reprezentand una dintre cele mai mari suferinte ale omenirii. Spre deosebire de alte maladii, în care bolnavul sufera el singur, alcoolismul cronic face numeroase victime în familie, lovind în destinul nevinovat al celor apropiati.
Fiu al unui sef de trib din Africa de Sud, originar din provincia Transkei, Nelson Rolihlahla Mandela s-a nascut la 18 iulie 1918 si a fost crescut dupa moartea tatalui sau de un unchi, sef al tribului Tembu. Educat in spiritul dreptatii si respectarii traditiei, Nelson a visat inca de mic sa fie conducatorul care va elibera poporul sau de sub dominatia odiosului regim de apartheid. Absolvent al scolii superioare metodiste din Healdtown, Mandela s-a inscris apoi la Fort Hare College, dar a fost exmatriculat pentru ca organizare o actiune de boicotare a orelor de curs.
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