Integration and Automation in Practice: CI/CD in Mule Integration and Automat...
Quantum Computing
1. Quantum Computing
Quantum Computing is the use of quantum-mechanical(Quantum
mechanics-including quantum field theory, is a fundamental theory in physics
which describes nature at the smallest – including atomic and subatomic –
scales.) phenomenon to perform computation.
According to Moore's law, the size of computer chips is
reduced by half every 6 months. If this is the case, then the various
components of the computer chip that are constantly being miniaturized will
start to behave under the rules of quantum mechanics instead of the usual
physics. This fundamental change of hardware has in many cases also
redefined the boundaries of theoretical computer science.
3. It’s fascinating to think about the power in our pocket—today’s smartphones
have the computing power of a military computer from 50 years ago that was
the size of an entire room. However, even with the phenomenal strides we
made in technology and classical computers since the onset of the computer
revolution, there remain problems that classical computers just can’t solve.
Many believe quantum computers are the answer.
4. Forget Moore's Law — Quantum Computers Are
Improving According to a Spooky 'Doubly Exponential
Rate'
According to Neven's Law,Named after Hartmut Neven, the director of the
Quantum Artificial Intelligence Lab at Google who first noticed the
phenomenon, the law dictates how quickly quantum processors are
improving, or getting faster at processing calculations, relative to regular
computers.
And it turns out, they're gaining on ordinary computers at a
spookily fast, "doubly exponential rate." That means that processing power
grows by a factor of 2^2^1 (4), then 2^2^2 (16), then 2^2^3 (256), then 2^2^4
(65,536), and so on. Doubly-exponential growth is so huge, it's hard to find
anything that grows so quickly in the natural world, according to Quanta.
"It looks like nothing is happening, nothing is happening, and
then whoops, suddenly you're in a different world,"
5. Quantum Properties
Three quantum mechanical properties
— superposition
— entanglement
— and interference
are used in quantum computing to manipulate the state of a
qubit.
6. Superposition
It states that- any two (or more) quantum states can be added together
("superposed") and the result will be another valid quantum state ; and
conversely, that every quantum state can be represented as a sum of two or
more other distinct states.
The principle of quantum superposition states simply that
a quantum particle can exists in 2 distinct locations at the same time.
According to this theory, an quantum particle can exist simultaneously in
multiple states, unless the operation of measurement is made.
7. To drive what quantum superposition means, closely observe the short video
above. The video depicts through animation, what is known as Qubits in
Quantum computing. A Qubit is the basic unit of quantum information, a
parallel to the Bit as the basic unit of classical information. As shown in the
video, a Qubit can be both 0 and 1 at the same time, till the time it is
observed. This property of the Qubit to be in a superposition of 2 states at the
same time is what provides the Quantum Computers with exponential
speedup when compared to Classical Computers.
8. Let’s take a step back from talking about Qubits and Quantum Computers.
Quantum superposition is something that happens throughout nature. let me
take the example of the most commonly know element on earth, water. I
hope all readers have a fair idea about how the water molecules are formed.
Oxygen shares it’s 2 electrons with each of the Hydrogen molecule and forms
a bond with them. According to classical chemistry, this sharing means that
the shared electrons reside in the vacant space between the Hydrogen and
Oxygen molecules. According to Quantum scientists, this is not exactly true.
The shared electrons actually exists in superposition between the Oxygen and
Hydrogen molecules. This means that the shared electrons are
simultaneously present in both Oxygen and Hydrogen molecules and the
position of these electrons need not always be in between the 2.
9.
10. Exponential speedup in Computation power
One of the most studied applications of quantum superposition is the
possible speedup in computation.
11. Consider that a quantum particle is going through this maze. Remember that
a quantum particle have the unique property of being at 2 places at the same
time, due to the principle of quantum superposition. So, when a quantum
particle encounters various paths to take within the maze, it can decide to
take all of those paths at the same time using superposition. If you think
about it, this process closely resembles the paradigm of parallel computing.
Due to quantum superposition, the quantum particle is able to navigate the
maze in exponentially less time than the classical bit.
12. A classical bit, on the other hand, does not posses this magical ability of
superposition. A classical bit is easier to imagine, as we can just imagine our
self going through a maze. At a time, we can explore only one of the paths in
the maze at a time. If the path the classical particle takes ends up in a dead
end, we have to backtrack all the way back and start again by choosing a
different path. As you can see, this is a time consuming process and we would
lose horribly if we were to race against the quantum particle.
13. Entanglement
Entanglement describes the relationship that exists between two or more
particles that interact in a way that makes it impossible to describe each
particle independently, even when the particles are separated by a large
distance. Rather, measurements of the particles reveal correlations, and as
such the particles must always be described as a quantum state of the whole
system. Entangled particles behave together as a system in ways that cannot
be explained using classical logic.
14.
15. The advantages is that all qubits work together with entangled therefore we
can solve any problem easily, as many combination is possible.
16. Interference
Finally, quantum states can undergo interference due to a phenomenon
known as phase. Quantum interference can be understood similarly to wave
interference; when two waves are in phase, their amplitudes add, and when
they are out of phase, their amplitudes cancel.
17. qubit
qubit or quantum bit (sometimes qbit) is the basic unit of information and
fundamental building block in quantum computing.
20. Quantum computing fundamentals
All computing systems rely on a fundamental ability to store and manipulate
information. Current computers manipulate individual bits, which store
information as binary 0 and 1 states. Quantum computers leverage quantum
mechanical phenomena to manipulate information. To do this, they rely on
quantum bits, or qubits. qubits consists with two level they are written in the
conventional Dirac—or “bra-ket’’—notation
21. When we say the spin of a particle is in a superposition of states, it simply
means it is in a linear combination of up spin and down spin. Here is the
equation in the Dirac notation.
The coefficient α is called the amplitude.
22. Here, the up spin and the down spin states are just the basis vectors. The
concept is similar to the x, y basis vectors in the law of motion in Physics.
The Dirac notation |ψ⟩ is just a short form for a matrix.
23. |0⟩ and |1⟩ are the two orthogonal basis vectors that are encoded as:
It also has a dual form written as:
The math is simply matrix multiplication and linear algebra. We
just shorten it with Dirac notation.
24. We can visualize the superposition as a point lying on the surface of a unit
sphere.
26. Due to the nature of quantum physics, the destruction of information in
a gate will cause heat to be evolved which can destroy the superposition
of qubits.
27. Quantum Gates
Quantum Gates are similar to classical gates, but do not have a
degenerate output. i.e. their original input state can be derived from their
output state, uniquely. They must be reversible.
This means that a deterministic computation can be performed on a
quantum computer only if it is reversible. Luckily, it has been shown that
any deterministic computation can be made reversible.(Charles Bennet,
1973)
28. Simplest gate involves one qubit and is called a Hadamard Gate (also known
as a square-root of NOT gate.) Used to put qubits into superposition.
Quantum Gates - Hadamard
29. A gate which operates on two qubits is called a Controlled-NOT (CN) Gate. If
the bit on the control line is 1, invert the bit on the target line.
Quantum Gates - Controlled NOT
30. We can build a reversible logic circuit to calculate multiplication by 2 using CN
gates arranged in the following manner:
31. A gate which operates on three qubits is called a Controlled Controlled NOT
(CCN) Gate. If the bits on both of the control lines is 1,then the target bit is
inverted.