If Your Quantum Computer is Imperfect, Try a Classical System to Simulate It

Atom Orange

Imperfections Lower the Simulation Cost of Quantum Computers

Read More…

+  With a few quantum bits, an ideal quantum computer can process vast amounts of information in a coordinated way, making it significantly more powerful than a classical counterpart. This predicted power increase will be great for users but is bad for physicists trying to simulate on a classical computer how an ideal quantum computer will behave.

+  Now, a trio of researchers has shown that they can substantially reduce the resources needed to do these simulations if the quantum computer is “imperfect”.

Today’s state-of-the-art quantum computers—including Sycamore—are NISQ devices. The algorithms the team used are based on so-called tensor network methods, specifically matrix product states (MPS), which are good for simulating noise and so are naturally suited for studying NISQ devices. MPS methods approximate low-entangled quantum states with simpler structures, so they provide a data-compression-like protocol that can make it less computationally expensive to classically simulate imperfect quantum computers.

+  In 2019, Google claimed to have achieved the quantum computing milestone known as “quantum advantage,” publishing results showing that their quantum computer Sycamore had performed a calculation that was essentially impossible for a classical one.

+  More specifically, Google claimed that they had completed a three-minute quantum computation—which involved generating random numbers with Sycamore’s 53 qubits—that would take thousands of years on a state-of-the-art classical supercomputer, such as IBM’s Summit.

+  IBM quickly countered the claim, arguing that more efficient memory storage would reduce the task time on a classical computer to a couple of days. The claims and counterclaims sparked an industry clash and an intense debate among supporters in the two camps.

Source:  Physics.  Jordi Tura,  Imperfections Lower the Simulation Cost of Quantum Computers…

Content may have been edited for style and clarity. The “+” to the left of paragraphs or other statements indicates quoted material from “Source:” document. Boldface title is original title from “Source:” Italicized statements are directly quoted from “Source:” document. Image sources are indicated as applicable.

Share this article ...

Our Mission

At The Qubit Report, our mission is to promote knowledge and opinion of quantum computing from the casual reader to the scientifically astute.  Because Quantum is Coming.

Einstein Stroll