Alice and Bob are fictional characters often used to describe cryptographic protocols. We introduced them in a previous article on quantum cryptography. Picture a situation where Alice and Bob are living in different parts of the world and where Alice would like to communicate two classical bits of information to Bob by sending him only[…]
Cloud-based quantum computing is the invocation of quantum emulators, simulators or processors through the cloud. Increasingly, cloud services are being looked on as the method for providing access to quantum processing. Cloud-based quantum computing can be used in several contexts, such as: Teaching: teachers can use cloud-based quantum computing to help their students better understand[…]
The worldwide quest to build practical quantum computers is undergoing a critical period. Fault-tolerant quantum computers will soon provide significant computational speedups for problems like factoring, search, or linear algebra, etc. During the next few years, a number of different quantum devices will become available to the public. Over the past decade, a wide variety[…]
Mixing quantum computing and Artificial Intelligence (AI) may sound like a new buzzword. However, since quantum computing advances are hinting at profound changes in the very notions of computation, it is natural to reexamine various branches of computer science in the light of these disruptions. And … AI is no exception As usual, before entering[…]
In a series of posts, we introduced various quantum computing concepts: How information and quantum mechanics are related ? What is quantum computing ? What are Bell states ? What is quantum teleportation ? What is quantum error correction ? What are topological quantum computer ? In addition to these concepts, we devoted two posts[…]
We have been talking about quantum computing for a few weeks now. We have talked about its theoretical principles (quantum entanglement, no-cloning theorem, …) and its applications, especially in the contexts of cryptography and complexity. Yet, we haven’t talk much about practicalities. The outstanding problem with entangled superpositions of spinning electrons, polarized photons or most[…]
Cryptography is the cornerstone of secure communication. Broadly speaking, cryptography deals with creating and studying protocols that prevent third parties (public or adversaries) from reading messages. It is strongly tied to information security topics such as confidentiality, data integrity, identification, authentication or non-repudiation / proof. Today’s cryptography is heavily based on mathematics: cryptographic algorithms are[…]
In classical computing, a bit is a single piece of information that can exist in two states (1 or 0, true or false). As we have seen before, quantum computing uses qubits (2-states quantum systems) instead. Qubits can be represented by the mean of an imaginary sphere (called a Bloch sphere): Whereas a classical bit[…]
Building a quantum device in the real world means having to deal with errors: any qubit stored unprotected or transmitted through a communications channel will inevitably come out changed. To be protected, quantum devices have to be kept at extremely cold temperatures (a few milikelvins) and shielded from electromagnetic radiation. Quantum error correction is used[…]
In this new post on quantum computing, we are going to talk about quantum teleportation. Teleportation. OMG. Yes, I can see those stars sparking in your geeky eyes … So … first, let’s clarify a few things, shall we ? Quantum teleportation is a communications protocol that transfers the quantum state of a system to[…]
In a previous post, we introduced the basic concepts of quantum computing, during which quantum entanglement, Bell states and usual quantum gates such as Hadamard’s or Pauli’s were quickly addressed. Today, we’re going to explore some of these concepts and start having fun with quantum programming to illustrate these ideas. Quantum entanglement Quantum entanglement is a[…]
Quantum computing as made the headlines recently. At IBM’s inaugural Index Developer Conference held in San Francisco, the company showed off its latest prototype: a quantum computing rig housing 50 qubits, one of the most advanced machines currently in existence. Google Quantum AI Lab announced Bristlecone, its new quantum processor, at the annual American Physical[…]
This is our fifth part of a series of posts on (a few selected) hidden realities : many-worlds interpretation of quantum mechanics, multiverse linked to the space-time geometries and dynamics, higher dimensional multiverse, holographic multiverse and simulated multiverse. For the previous posts, please see: On hidden realities (part 1) – Many-worlds interpretation of quantum mechanics[…]
This is our fourth part of a series of posts on (a few selected) hidden realities : many-worlds interpretation of quantum mechanics, multiverse linked to the space-time geometries and dynamics, higher dimensional multiverse, holographic multiverse and simulated multiverse. For the previous posts, please see: On hidden realities (part 1) – Many-worlds interpretation of quantum mechanics On hidden[…]
This is our third part of a series of posts on (a few selected) hidden realities : many-worlds interpretation of quantum mechanics, multiverse linked to the space-time geometries and dynamics, higher dimensional multiverse, holographic multiverse and simulated multiverse. For the previous posts, please see: On hidden realities (part 1) – Many-worlds interpretation of quantum mechanics[…]
This is the second part of a series of posts on (a few selected) hidden realities : many-worlds interpretation of quantum mechanics, multiverse linked to the space-time geometries and dynamics, higher dimensional multiverse, holographic multiverse and simulated multiverse. For the previous posts, please see: On hidden realities (part 1) – Many-worlds interpretation of quantum mechanics Space-time[…]
Since I took a 4 weeks vacation, and I’m getting really bored, it gave me time to push a (muuuuch) needed upgrade to this blog and to publish a couple of posts. I wanted to publish a few posts on multiverse for a long time. I stole the title of this series of post, “On[…]
Recently, there’s been a lot of talk about the Higgs boson. A month ago, both teams from CMS and ATLAS experiments at LHC have announced independently the discovery of a previously unknown boson of mass between 125–127 GeV/c2. The characteristics of this new particle are consistent whith the ones of the Higgs Boson. Without getting[…]
Let’s start this new year with a fundamental question: what kind of a nerd am I ? As some may know, I’m a huge fan on “The Big Bang Theory” TV series. How could it be otherwise ? Geeks, physicists, addiction to comics and a cute neighbor. The perfect cocktail. Yep, I’m the kind of[…]
As promised a couple of posts ago, here are a few words on General Relativity. I’ll try to concentrate on the principles by not focusing (too much) on technicalities. Keeping this post concise is quite a challenge, because of the incredible beauty lying in the physics and mathematics of General Relativity. A thing of beauty[…]
Well, I wish I were… Anyhoo, I went to the movies and saw Iron Man II a few hours ago. Slightly disappointing, maybe because I was expecting much from Don Cheadle and Mickey Rourke, and, well, because the french speaking scenes were so totally weird (I had no idea that people from Monaco were speaking[…]
Okay, at last, a first post about information and quantum mechanics. Let’s begin with the very basic building blocks of all this: quantum states. A qubit is a short for “quantum bit”. It is to quantum information what a bit is to computer information. Bits and qubits are nevertheless quite different. A computer bit is[…]
Found this week-end two interesting books at Decitre Bellecour. Springer Verlag is usually quite expensive, but thanks to the Yellow Sales, I could get them at a very reasonable price ! Cool. Don’t know if I’ll be able to resist buying a few more of these… Riemannian Manifolds,J.M.Lee, SpringerISBN 0-387-20158-0 Fractals and Chaos,B.Mandelbrot,[…]