Skip to main content

Quantum no-hiding theorem experimentally confirmed for first time

Quantum no-hiding theorem experimentally confirmed for first time

March 7, 2011 by Lisa Zyga
Quantum no-hiding theorem experimentally confirmed for first time
In part (a), the three qubits (the magnetic nuclei of hydrogen, fluorine, and carbon) are shown, with the quantum information stored in the first qubit. In part (b), the quantum information has been transferred from the first qubit to the …more
( -- In the classical world, information can be copied and deleted at will. In the quantum world, however, the conservation of quantum information means that information cannot be created nor destroyed. This concept stems from two fundamental theorems of quantum mechanics: the no-cloning theorem and the no-deleting theorem.
A third and related theorem, called the no-hiding theorem, addresses information loss in the . According to the no-hiding theorem, if information is missing from one system (which may happen when the system interacts with the environment), then the information is simply residing somewhere else in the Universe; in other words, the missing information cannot be hidden in the correlations between a system and its environment. Physicists Samuel L. Braunstein at the University of York, UK, and Arun K. Pati of the Harish-Chandra Research Institute, India, first proved the no-hiding theorem in 2007. Until now, however, the no-hiding theorem has been a purely theoretical concept.
Now for the first time, a team of physicists consisting of Pati, along with Jharana Rani Samal (deceased) and Anil Kumar of the Indian Institute of Science in Bangalore, India, has experimentally tested and confirmed the no-hiding theorem. The physicists have published their study on the no-hiding theorem test in a recent issue of . The work is dedicated to the memory of Samal, who died in November 2009 on her 27th birthday, and who performed all of the experimental work of the paper.
“In quantum information science, two fundamental theorems have been the no-cloning and the no-deleting theorems,” Pati told “They bring out essential differences between quantum and classical information and are also intimately connected to the conservation of quantum information. However, these two theorems cannot be tested experimentally in the sense that these operations are not allowed by . (Since these operations are not allowed, we cannot implement them in the laboratory.) The best that one can do is to experimentally demonstrate the approximate cloning or approximate deleting of quantum information. (Note that the latter operations are allowed because you are not demanding exact cloning or exact deleting.) Now, the no-hiding theorem is a first of its kind, which is also related to the conservation of quantum information and can be subjected to experimental tests. In this respect, our experiment is also the first experimental test of a no-go theorem in quantum information. It is important to demonstrate experimentally whether the prediction of quantum theory comes true or not.”
The scientists performed the test using nuclear magnetic resonance (NMR), a technique that has previously been used to test other  protocols, such as Shor’s algorithm and Grover’s algorithm, and is also used in magnetic resonance imaging (MRI). Here, the scientists used three magnetic nuclei of hydrogen, fluorine, and carbon from a large molecule (13CHFBr2). The three magnetic nuclei represent three qubits, one of which contains the original information, and the other two of which are ancilla qubits and are prepared in fixed states.
In order to make the first qubit “lose” its information, the scientists had to make the system undergo a bleaching process. In their experiment, they bleached the system through quantum state randomization, in which the qubit transforms from a pure state to a mixed state. Although the randomization operation causes the qubit to appear to lose the information contained in the pure state, the scientists showed that the information could be found in one of the two ancilla qubits. They also demonstrated how to use the ancilla qubits to reconstruct the original state, showing that no information was hiding in the correlations between the original qubit and the ancilla qubits, which is the essence of the no-hiding theorem.
“The greatest challenge for carrying out this experiment by NMR was the design of the pulse sequence for the ‘randomization operator,’” Kumar said. “This was achieved here by using a novel algorithmic technique developed in our laboratory by Ashok Ajoy (an M.Sc. student who has now gone to MIT, Boston, to do his Ph.D.). His method uses graphs of a complete set of base operators and develops an algorithmic technique for finding the decomposition of a given unitary operator into basis operators and their equivalent pulse sequences (to be published).”
In the future, the physicists plan to test the no-hiding theorem in more complex situations, such as in the context of coherent quantum teleportation, which will require the control and manipulation of a larger number of qubits. Overall, the quantum no-hiding theorem could have applications in areas such as quantum communication through private quantum channels, as well as black hole evaporation.
More information: Jharana Rani Samal, et al. “Experimental Test of the Quantum No-Hiding Theorem.” Physical Review Letters. 106, 080401 (2011). DOI: 10.1103/PhysRevLett.106.080401

Read more at:

Popular posts from this blog

Hidden Wiki

Welcome to The Hidden WikiNew hidden wiki url 2015 http://zqktlwi4fecvo6ri.onion Add it to bookmarks and spread it!!!
Editor's picks Bored? Pick a random page from the article index and replace one of these slots with it.
The Matrix - Very nice to read. How to Exit the Matrix - Learn how to Protect yourself and your rights, online and off. Verifying PGP signatures - A short and simple how-to guide. In Praise Of Hawala - Anonymous informal value transfer system. Volunteer Here are five different things that you can help us out with.
Plunder other hidden service lists for links and place them here! File the SnapBBSIndex links wherever they go. Set external links to HTTPS where available, good certificate, and same content. Care to start recording onionland's history? Check out Onionland's Museum Perform Dead Services Duties. Introduction - Clearnet search engine for Tor Hidden Services (allows you to add new sites to its database). DuckDuckGo - A Hidden S…


Good News [May 08, 2015]: IDM developers got smarter, but the crackers are always a step ahead. Follow this article and send an email to if you are desperate. I can NOT post any crack here for legal reasons. Happy Downloading with IDM. ;) *********** first tip is to use latest crack for idm from idm universal web crack and make sure u are using all latest vers I am sure many of us are too much dependent on Internet Download Manager a.k.a. IDM. The main reason didn’t permanently switch to linux was IDM. I mainly use it for batch downloading and download streaming videos. Till yesterday, IDM was working fine with me (of course with fake serial numbers, keygen, crack, patch etc. which could be found with little effort). But few days ago, with the latest update version 6.18 build 7 (released on Nov 09, 2013) Internet Download Manager was literally had a breakthrough and crushed all the serial numbers, …

DoubleAgent Attack Turns Your Antivirus Into Malware And Hijacks Your PC

Short Bytes: Cybellum security researchers have uncovered a new attack mechanism that can be used to take control of your antivirus and turn it into a malware. Called DoubleAgent, this attack exploits an old and undocumented vulnerability in Windows operating system. This Zero Day code injection technique affects all major antivirus vendors and has the power to hijack permissions. The security researchers from Cybellum have found a new technique that can be used by the cybercriminals to hijack your computer by injecting malicious code. This new Zero-Day attack can be used to take full control over all the major antivirus software. Instead of hiding from the antivirus, this attack takes control of the antivirus itself. Called DoubleAgent, this attack makes use of a 15-year-old legitimate feature of Windows (read vulnerability)–that’s why it can’t be patched. It affects all versions of Microsoft Windows. Cybellum blog mentions that this flaw is still unpatched by most antivirus v…