From UPSC perspective, the following things are important :
Prelims level : Quantum Supremacy
Mains level : Quantum Computing
- A draft research paper claimed Google researchers have achieved a long-ought-after goal in physics called “quantum supremacy”.
- It refers to a quantum computer solving a problem that cannot be expected of a classical computer in a normal lifetime.
- This relates to the speed at which a quantum computer performs.
- The phrase “quantum supremacy” was coined in 2011 by John Preskill, Professor of Theoretical Physics at the California Institute of Technology in a speech.
- According to reports the quantum processor took 200 seconds to perform a calculation that the world’s fastest supercomputer, Summit, would have taken 10,000 years to accomplish.
- The draft paper is believed to be an early version of a paper that has been submitted to a scientific journal.
What is quantum computing?
- Quantum computing takes advantage of the strange ability of subatomic particles to exist in more than one state at any time.
- Due to the way the tiniest of particles behave, operations can be done much more quickly and use less energy than classical computers.
How is Quantum computer different from a traditional computer?
- What differentiates a quantum computer from a traditional computer is the way the two store information.
- Quantum computers perform calculations based on the probability of an object’s state before it is measured – instead of just 1s or 0s – which means they have the potential to process exponentially more data compared to classical computers.
- Classical computers carry out logical operations using the definite position of a physical state.
- These are usually binary, meaning its operations are based on one of two positions. A single state – such as on or off, up or down, 1 or 0 – is called a bit.
- In quantum computing, operations instead use the quantum state of an object to produce what’s known as a qubit.
- These states are the undefined properties of an object before they’ve been detected, such as the spin of an electron or the polarisation of a photon.
- Quantum mechanics (QM) is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
- It is the body of scientific laws that describe the wacky behavior of photons, electrons and the other particles that make up the universe.