Advanced Topics:

1. Advanced Topics: Quantum Computing

2. Peter Phillips, Ross Baker, Scott Brinks

3. Discussing Key Topics • Introduction to Quantum Computers: • History and concept • What Quantum Computers are? • How Quantum Computers work? • Advantages • Disadvantages • Most typical uses: • Cryptography • Quantum Communication • Artificial Intelligence • Large Scale Applications

4. Introduction

5. Introduction • Although computers have become more compact and considerably faster in performing their task, the task remains the same: • Manipulate and interpret an encoding of binary bits into a useful computational result.

6. There is one key difference between a classical computer and a quantum computer: • A classical computer obeys the well understood laws of classical physics • A quantum computer harnesses physical phenomenon unique to quantum mechanics to create a fundamentally new method of processing.

7. The ideas were formulated in the mid-eighties, and the first prototypes weren’t built until the mid-to-late-nineties. • Quantum computing is a fairly new science • Except for a few basic mathematical calculations, all applications associated with quantum computing are purely theoretical

8. What is quantum computing?

9. What is quantum computing? • In a quantum computer, the fundamental unit of information (called a quantum bit or qubit), is not binary but rather more quaternary in nature.

10. This qubit property arises as a direct consequence of its adherence to the laws of quantum mechanics which differ radically from the laws of classical physics. • A qubit can exist not only in a state corresponding to the logical state 0 or 1 but also in states corresponding to a blend or superposition of these classical states

11. In other words, a qubit can exist as a zero, a one, or simultaneously as both 0 and 1, with a numerical coefficient representing the probability for each state • This may seem counterintuitive because everyday phenomenon are governed by classical physics, not quantum mechanics -- which takes over at the atomic level

12. This unique characteristic, among others, makes the current research in quantum computing not merely a continuation of today's idea of a computer, but rather an entirely new branch of thought

13. The details(How it works)

14. In a traditional computer, information is encoded in a series of bits, and these bits are manipulated via Boolean logic gates arranged in succession to produce an end result The details(How it works)

15. A quantum computer manipulates qubits by using a series of quantum gates, each a unitary transformation acting on a single qubit or pair of qubits • In applying these gates in succession, a quantum computer can perform a complicated unitary transformation to a set of qubits which are in some initial state • The qubits can then be measured, with this measurement serving as the final computational result

16. The similarity in calculation between a classical and quantum computer suggests that, in theory, a classical computer can accurately simulate a quantum computer

17. Can a classical computer do anything a quantum computer can? • If so, why bother with quantum computers?

18. Although a classical computer can theoretically simulate a quantum computer, it is incredibly inefficient • So much so, that a classical computer is effectively incapable of performing many tasks that a quantum computer could perform with ease

19. The simulation of a quantum computer on a classical one is a computationally hard problem because the correlations among quantum bits are qualitatively different from correlations among classical bits

20. Advantages

21. Speed! • Quantum Computers have the potential to solve certain calculations billions of times faster than any silicone-based computer • Solve problems that would take millions of years to figure out using present-day computers

22. Continuity • Algorithms used in classical computers can be directly applied to quantum computers • Revolutionary concept can be used with current framework of computing

23. Disadvantages • Technology required is currently beyond our reach • Not practical for certain applications • (word processing, etc) • Three obstacles: • Decoherence (quantum decay) • Error correction • Hardware architecture

24. Theoretical Uses • Cryptography • Large-Scale Applications • Communication • Artificial Intelligence

25. Cryptography • Most common form of encryption is known as RSA • Relies heavily on factoring huge numbers into primes • Quantum factorization algorithm • Could break extremely complex code in a matter of seconds

26. Large Scale Computing • Solve complex math algorithms • “Needle-in-a-haystack” algorithm • Exhaustively searching a large set of possible solutions • Large scale database management

27. Artificial Intelligence • Theories suggest that every physical object in the universe is a quantum computer • If all computers are functionally equivalent then computers should be able to model every physical process • Ultimately, computers will be capable of simulating conscious rational thought

28. Quantum Communication • Quantum information cannot be measured without disrupting it • Attempts to eavesdrop on a message would set off an alarm • Automatic shut down of transmission

29. Conclusion • Based on quantum laws rather than physical laws • Quantum computers basic building blocks are qubits (quantum bits) rather than binary bits • Some of possible advantages are: • Speed: • very fast applications • Continuity: • use current algorithms

30. Conclusion • Some of possible disadvantages are: • Theoretical: • Current technology is out of our reach • Impractical: • Too fast for common applications • Some of possible uses are: • Cryptography • Large Scale Computing • Artificial Intelligence • Quantum Mechanics

31. Thanks for listening Questions anyone?