Editors Note: Do you ever feel like a fish out of water? Try being a tech novice and talking to an engineer at a place like Google. Ask a Techspert is a new series on the Keyword asking Googler experts to explain complicated technology for the rest of us. This isnt meant to be comprehensive, but just enough to make you sound smart at a dinner party.

Quantum computing sounds like something out of a sci-fi movie. But its real, and scientists and engineers are working to make it a practical reality. Google engineers are creating chips the size of a quarter that could revolutionize the computers of tomorrow. But what is quantum computing, exactly?

The Keywords very first Techspert is Marissa Giustina, a research scientist and quantum electronics engineer in our Santa Barbara office. We asked her to explain how this emerging technology actually works.

What do we need to know about conventional computers when we think about quantum computers?

At a first glance, information seems like an abstract concept. Sure, information can be stored by writing and drawinghumans figured that out a long time ago. Still, there doesnt seem to be anything physically tangible about the process of thinking.

Enter the personal computer. Its a machinea purely physical objectthat manipulates information. So how does it do that, if its a physical machine and information is abstract? Well, information is actually physical. Computers store and process rich, detailed information by breaking it down. At a low level, a computer represents information as a series of bits. Each bit can take a value of either [0] or [1], and physically, these bits are tiny electrical switches that can be either open [0] or closed [1]. Emails, photos and videos on YouTube are all represented by long sequences of bitslong rows of tiny electrical switches inside a computer.

The computer computes by manipulating those bits, like changing between [0] and [1] (opening or closing a switch), or checking whether two bits have equal or opposite values and setting another bit accordingly. These bit-level manipulations are the basis of even the fanciest computer programs.

Ones and zeros, like "The Matrix." Got it. So then what is a quantum computer?

A quantum computer is a machine that stores and manipulates information as quantum bits, or qubits, instead of the classical bits we were talking about before. Quantum bits are good at storing and manipulating a different kind of information than classical bits, since they are governed by rules of quantum mechanicsthe same rules that govern the behavior of atoms and molecules.

Whats the difference between a bit and a qubit?

This is where it gets more complicated. Remember that a classical bit is just a switch: it has only two possible configurations: [open] or [closed]. A qubits configuration has a lot more possibilities. Physicists often think of a qubit like a little globe, with [0] at the north pole and [1] at the south pole, and the qubits configuration is represented by a point on the globe. In manipulating the qubit, we can send any point on the globe to any other point on the globe.

At first, it sounds like a qubit can hold way more information than a regular bit. But theres a catch: the rules of quantum mechanics restrict what kinds of information we can get out of a qubit. If we want to know the configuration of a classical bit, we just look at it, and we see that the switch is either open [0] or closed [1]. If we want to know the configuration of a qubit, we measure it, but the only possible measurement outcomes are [0] (north pole) or [1] (south pole). A qubit that was situated on the equator will measure as [0] 50 percent of the time and [1] the other 50 percent of the time. That means we have to repeat measurements many times in order to learn about a qubits actual configuration.

Here is the original post:

Ask a Techspert: What is quantum computing? - blog.google

- This Week in Tech: What on Earth Is a Quantum Computer? - The New York Times - December 7th, 2019
- Quantum Computers Are About to Forever Change Car Navigation - autoevolution - December 7th, 2019
- Global Quantum Computing Market Expected to Deliver Dynamic Progression until 2028| D-Wave Systems, Google, IBM, Intel, Microsoft, 1QB Information... - December 7th, 2019
- Amazon is now offering quantum computing as a service with Braket for AWS - The Verge - December 2nd, 2019
- ColdQuanta's Latest Ultracold Technology Heads to the International Space Station - Business Wire - December 2nd, 2019
- Researchers Discover New Way to Split and Sum Photons with Silicon - UT News | The University of Texas at Austin - December 2nd, 2019
- Archer Materials invited to chair quantum computing session at London conference - Proactive Investors Australia - December 2nd, 2019
- Archer Materials to chair Quantum Computing session at London Quantum.Tech Conference in 2020 - Proactive Investors Australia - November 30th, 2019
- The Future of Computing could be Magnetic - Robert Lea - Medium - November 30th, 2019
- Innovate, and grow - Economic Times - November 30th, 2019
- Tech news: The quantum internet is on the way - IOL - November 22nd, 2019
- Device Puts Photons in the Fast Lane - Optics & Photonics News - November 22nd, 2019
- Race is on to build quantum-proof encryption - Financial Times - November 21st, 2019
- Atos partners with Zapata to deliver complete quantum computing solution to the enterprise - Quantaneo, the Quantum Computing Source - November 20th, 2019
- NTT offers researchers $1 million salaries in bid to lure top talent in cryptography, quantum computing - The Japan Times - November 20th, 2019
- Information overload: The promise and risk of quantum computing - Bulletin of the Atomic Scientists - November 17th, 2019
- D-Wave sticks with its approach to quantum computing - TechCrunch - November 17th, 2019
- The Quantum Computing Threat to American Security - The Wall Street Journal - November 17th, 2019
- Dell Technologies on democratising 5G and the future of quantum computing - ZDNet - November 17th, 2019
- How Serious Is the Threat of Quantum Computing to Crypto? - Finance Magnates - November 17th, 2019
- Superconducting quantum computing - Wikipedia - October 6th, 2019
- Quantum computing | MIT News - October 6th, 2019
- How Do Quantum Computers Work? - sciencealert.com - October 2nd, 2019
- What is Quantum Computing? - Definition from Techopedia - October 2nd, 2019
- How Quantum Computers Work | HowStuffWorks - September 5th, 2019
- Quantum computing could change everything, and IBM is ... - May 15th, 2019
- Quantum Computing - Intel - April 29th, 2019
- IBM expands universities in its quantum computing research ... - April 25th, 2019
- Quantum computing is a marathon not a sprint | VentureBeat - April 22nd, 2019
- The CIO's Guide to Quantum Computing - Smarter With Gartner - April 19th, 2019
- This Startup Just Raised $21 Million To Bring Quantum ... - April 18th, 2019
- What is Quantum Computing ? Top 18 Quantum Computing ... - April 6th, 2019
- The promise of quantum computing - businessinsider.com - March 27th, 2019
- Quantum computing is coming: Heres why we need to get our ... - March 23rd, 2019
- Quantum computing will break your encryption in a few ... - March 21st, 2019
- Microsoft has formed a coalition to promote quantum computing ... - March 19th, 2019
- Quantum computing for everyone | Michael Nielsen - March 12th, 2019
- IBM hits quantum computing milestone, may see 'Quantum ... - March 6th, 2019
- Its Time You Learned About Quantum Computing | WIRED - March 6th, 2019
- Microsofts quantum computing network takes a giant leap ... - March 2nd, 2019
- When Will Quantum Computing Have Real Commercial Value ... - February 25th, 2019
- The Case Against Quantum Computing - IEEE Spectrum - February 22nd, 2019
- How Does Quantum Computing Work? - ExtremeTech - January 31st, 2019
- Quantum technology - Wikipedia - January 23rd, 2019
- CES 2019: IBM's Q System One Is the Rock Star Quantum ... - January 13th, 2019
- Quantum Computing | The MIT Press - January 11th, 2019
- IBM thinks outside of the lab, puts quantum computer in a box - January 11th, 2019
- IBM unveils its first commercial quantum computer - January 9th, 2019
- A new type of quantum computer has smashed every record ... - December 21st, 2018
- China bet big on quantum computing. Now the US races to ... - October 26th, 2018
- US takes first step toward a quantum computing workforce ... - September 17th, 2018
- China bet big on quantum computing. Now the ... - money.cnn.com - September 17th, 2018
- The reality of quantum computing could be just three years ... - September 12th, 2018
- The quantum computing race the US cant afford to lose - September 3rd, 2018
- Quantum Computing | USRA - August 30th, 2018
- What Is Quantum Computing? The Complete WIRED Guide | WIRED - August 22nd, 2018
- Quantum Computing Market Research Report- Forecast 2022 | MRFR - August 1st, 2018
- Two Quantum Computing Bills Are Coming To Congress - July 5th, 2018
- Senate bills would make quantum computing a priority - June 10th, 2018
- What is quantum computing? - Definition from WhatIs.com - February 5th, 2018
- The Era of Quantum Computing Is Here. Outlook: Cloudy ... - January 26th, 2018
- IBM puts its quantum computer to work in relaxing, nerdy ASMR ... - January 8th, 2018
- Quantum computing is going to change the world. Here's what ... - January 8th, 2018
- Is Quantum Computing an Existential Threat to Blockchain ... - December 25th, 2017
- What is Quantum Computing? | SAP News Center - December 23rd, 2017
- Quantum Computing Explained | What is Quantum Computing? - December 21st, 2017
- New silicon structure opens the gate to quantum computers - December 14th, 2017
- Microsoft offers developers a preview of its quantum ... - December 12th, 2017
- Quantum Computing Is the Next Big Security Risk | WIRED - December 8th, 2017
- Yale Professors Race Google and IBM to the First Quantum ... - November 16th, 2017
- IBM's processor pushes quantum computing ... - engadget.com - November 16th, 2017
- Quantum computing - news.microsoft.com - November 1st, 2017
- Intel Takes First Steps To Universal Quantum Computing - October 13th, 2017
- Qudits: The Real Future of Quantum Computing? - IEEE Spectrum - October 13th, 2017
- quantum computing - engadget.com - October 13th, 2017
- Quantum Computing | Intel Newsroom - October 13th, 2017
- What will you actually use quantum computing for? | ZDNet - October 11th, 2017
- Here's what quantum computing is and why it matters - October 6th, 2017
- Microsoft just upped its multi-million bet on quantum computing - ZDNet - September 7th, 2017
- Microsoft's Aussie quantum computing lab set to scale up next-gen ... - ARNnet - September 7th, 2017

## Recent Comments