# How can a quantum computer prove that it is superior?

- September 28, 2023
- Posted by: OptimizeIAS Team
- Category: DPN Topics

No Comments

**How can a quantum computer prove that it is superior?**

**Subject :Science and Tech**

**Section: Awareness in computers **

**Source: ****TH**

**Quantum Computing (QC):**

- QC technology promises more speed and more efficient problem-solving abilities, challenging the boundaries set by classical, conventional computing.
**Quantum supremacy**is the term used for these computing techniques as**QCs**have the**ability to solve some problems much faster than a classical computer**.

**Facing the quantum challenge:**

**Quantum computers**use**quantum bits, or qubits**, whereas classical computers use binary bits (0 and 1).**Qubits**are**fundamentally different from classical bits**as they can have the value 0 or 1, as a classical bit can, or a value that’s a combination of 0 and 1, called a**superposition**.**Superposition****states allow qubits to carry more information.**This capacity of quantum computers allows them to perform a disproportionately greater number of operations.

**Qubits also exhibit entanglement**, meaning that**two qubits can be intrinsically linked regardless of their physical separation.**This property allows quantum computers to tackle complex problems that may be out of reach of classical devices.**Scalability- Biggest advantage of QCs:**- In classical computers, the processing power grows linearly with the number of bits. While in QCs it grows
**exponentially as 2**where^{n},**n is the number of qubits**.

- In classical computers, the processing power grows linearly with the number of bits. While in QCs it grows

**#P-hard problems:**

**Quantum circuits**(core of QCs) consist of**qubits**and**quantum gates**.- In such a circuit, a quantum gate could manipulate the qubits to perform specific functions, leading to an output.
**Classical computers**struggle with**#P-hard problems**– a set of problems that includes**estimating the probability**that random quantum circuits will yield a certain output.**#P-hard problems**are a subset of**#P problems**, which are all counting problems.- If a problem is
**#P-hard,**then it is so challenging that if you can efficiently solve it, you can also efficiently solve every other problem in the #P class by making certain types of transformations.

**Taking the Cayley path:**

**Cayley path**is a mathematical construct developed by**Dr. Movassagh**to prove that certain classes of problems can be solved by quantum computers but not by classical computers.

**Quantum complexity theory:**

**Dr. Mossavagh’s**paper shows that there exists a problem that presents a computational barrier to classical computers but not to quantum computers (assuming**a quantum computer can crack a #P-hard problem)**.- The theory also challenges the extended
**Church-Turing thesis,**which is the idea that classical computers can efficiently simulate any physical process. - The
**establishment of quantum supremacy**will have a positive impact in the field of**cryptography**.

__Quantum Technology__

- Quantum Technology is based on the principles of Quantum mechanics that was developed in the early 20th century to describe nature at the scale of atoms and elementary particles.
- The first phase of this revolutionary technology has provided the foundations of our understanding of the physical world, including the interaction of light and matter, and led to ubiquitous inventions such as lasers and semiconductor transistors.
- A second revolution is currently underway with the goal of putting properties of quantum mechanics in the realms of computing.

__Properties of Quantum Computing__

**Superposition**– It is the ability of a quantum system to be in multiple states simultaneously.**Entanglement**– It means the two members of a pair (Qubits) exist in a single quantum state. Changing the state of one of the qubits will instantaneously change the state of the other one in a predictable way. This happens even if they are separated by very long distances.- Einstein called spooky ‘action at a distance’.

**Interference**– Quantum interference states that elementary particles (Qubits) can not only be in more than one place at any given time (through superposition), but that an individual particle, such as a photon (light particles) can cross its own trajectory and interfere with the direction of its path.

**How does a computer use quantum superposition?**

- The
**bit**is the**fundamental unit**of a**classical computer.**- Its value is
**1**if a corresponding transistor is on and**0**if the transistor is off. - The transistor can be in one of two states at a time – on or off – so a bit can have one of two values at a time, 0 or 1.

- Its value is
- In the
**Qubits,**instead of being either 1 or 0, the**information is encoded in a superposition:**say,**45% 0 plus 55% 1.** - This is entirely unlike the two separate states of 0 and 1 and is the
**third kind of state.** **One qubit**can encode**two states.****Five qubits**can**encode 32 states**. A computer with**N qubits**can encode**2N states**– whereas a computer with**N transistors**can**only encode 2 × N states.**- So a qubit-based computer
**can access more states than a transistor-based computer**, and thus access more computational pathways and solutions to more complex problems. - It’s typically a particle like an
**electron.**

**What are Transmons:**

- In
**quantum computing,**and more specifically in**superconducting quantum computing,**a**transmon**is a type of**superconducting charge qubit**that was designed to have reduced sensitivity to charge noise. **Google**and**IBM**have been known to use**transmons**, where**pairs of bound electrons oscillate between two superconductors**to designate the two states.

__Potential Applications For Quantum Computing__

- Machine Learning
- Computational Chemistry
- Financial Portfolio Optimisation
- Secure Communication
- Disaster Management
- Pharmaceutical
- Logistics and Scheduling
- Cyber Security
- Augmenting Industrial revolution 4.0

__National Mission on Quantum Technology and Applications (NMQTA)__

- Union Budget 2020-21 proposed to spend Rs 8,000 crore on the newly launched NMQTA.
- In 2018, the Department of Science & Technology unveiled a programme called Quantum-Enabled Science & Technology (QuEST) and committed to investing Rs. 80 crore over the next three years to accelerate research.
- The mission seeks to develop quantum computing linked technologies amidst the second quantum revolution and make India the world’s third-biggest nation in the sector after the US and China.