Assignment 1

IUBAT – International University of Business Agriculture & Technology Assignment on Quantum Computer & Data Flow Machine Course Code: CSC 461 Submitted to Krishna Das Faculty, CSE Department Submitted By MD. Yousuf Hassan ID 14203100 Section: EVE Program: BCSE Date of Submission 10th February 2017 Quantum Computer A quantum computer is a new type of computer that uses the unusual properties of quantum physics to solve problems that are impossible for a regular computer. Quantum computers use superposition and entanglement to perform operations on data. Traditional computer uses two definite states 0 and 1 where quantum computer uses quantum bits, which can be superpositions of states, which means a quantum bit or qubit can be one, zero or a superposition of both. Qubit A qubit or quantum bit is a unit of quantum information, where it has two states quantum mechanical system, such as the polarization of a single photon. However, quantum mechanics allows the qubit to be in a superposition of both states at the same time, a property which is fundamental to quantum computing. Traditional computer uses 0 and 1 where quantum computer uses 0s, 1s, or both at the same time. The superposition of states – along with the other quantum mechanical phenomena of entanglement and tunneling – enables quantum computers to manipulate enormous combinations of states at once. Image 1: A front runner in the pursuit of quantum computing uses single ions trapped in a vacuum. In general, a quantum computer with n qubits can be in superposition of up to 2^n different states simultaneously, which means if there is 2 qubits there will be 4 quantum superposition states, for 3 qubits there will be 8 quantum superposition states. The key to their "superness" is the fact that quantum bits or qubits are not bound by the conventions of time and space as we know them. Normal electrons spin either clockwise or anti-clockwise. Quantum electrons spin in both directions at once. This ability to transcend a single state of existence means that when they're used in computing, quantum electrons transform conventional "bits" into qubits. Conventional bits can be either a 1 or a 0, but qubits can be both at the same time. The Bloch Sphere The Bloch sphere is a representation of a qubit. It is a theoretical device that consists of tape of unlimited length that is divided into little squares. Figure 1: Bloch Sphere Each square can either hold a symbol (1 or 0) or be left blank. But in quantum Turing machine, the sysmbols on the tape can be either 0 or 1 or a superposition of 0 and 1; in other words the sysmbols are both 0 and 1 (and all points in between) at the same time. While a normal Turing machine can only perform one calculation at a time, a quantum Turing machine can perform many calculations at once. Qubits represent atoms, ions, photons or electrons and their respective control devices that are working together to act as computer memory and a processor. Because a quantum computer can contain these multiple states simultaneously. Some examples of quantum computers Image 2: D-Wave's 16-qubit quantum computer Image 3: The D-Wave 1,000 qubit processor. A 2000 qubit version will be available in 2017. (image courtesy of D-Wave) Image 4: The titan supercomputer can do 27,000 trillion calculations per second. OAK RIDGE NATIONAL LABORATORY Google’s Quantum Computer Image 5: Google’s Quantum Computer GOOGLE IS UPGRADING its quantum computer. Known as the D-Wave, Google’s machine is making the leap from 512 qubits—the fundamental building block of a quantum computer—to more than a 1000 qubits. And according to the company that built the system, this leap doesn’t require a significant increase in power, something that could augur well for the progress of quantum machines. Google and Nasa have been working on a lightning-fast quantum computer that is 3,600 times faster than a supercomputer at solving complex problems and 100 million times faster than a PC. Google's engineers just achieved a milestone in quantum computing: they’ve produced the first completely scalable quantum simulation of a hydrogen molecule. That’s big news, because it shows similar devices could help us unlock the quantum secrets hidden in the chemistry that surrounds us. Conclusion Quantum computers can compute, encode, and decode information much faster than the computers of today. This is why governments all over the world are looking to the technology of the quantum computer for security. With a quantum computer no information would be safe, the quantum computer would decode it in seconds. But, if a quantum computer were used to encrypt information, no computer today would be able to read it.  Data Flow Machine Dataflow machine is a computer architecture where primitive operations are caused by the availability of inputs or operands. This model is directly contrasts the traditional von Neumann architecture, where an instruction executed when the previous instruction in a defined sequence has been executed. But in dataflow architecture, an instruction executed when the operands required become available. In dataflow programming, as s user enters new values, they are instantly transmitted to the next logical actor or formula for calculation. Data Flow Models It uses a directed graph called a data dependence graph or dataflow graph. Each node of a data graph can be represented as an activity template. The general flow of the model is top to down. Terminology Arcs : flow of the data Nodes : represent operations Token : represent data and operations Firing: when data is available, operation is started, then result is sent to destination. Handshaking: Result is consumed Data Flow Example Figure 2: Dataflow example Static and Dynamic Dataflow Machines Designs that use conventional memory addresses as data dependency tags are called static dataflow machines. These machines did not allow multiple instances of the same routines to be executed simultaneously because the simple tags could not differentiate between them. Designs that use content-addressable memory (CAM) are called dynamic dataflow machines. They use tags in memory to facilliate parallelism. CAM is a special type of computer memory used in certain very high speed searching applications. İt compares input search data or tags against a table of stored data and returns the address of matching data. Uses of dataflow architecture Dataflow architecture has been successfully implemented in specialized hardware such as in digital signal processing, network routing, graphics proccessing and more. 5