Two Sides of Quantum Technology
Quantum Computing vs. Quantum Telecommunications
Welcome to Two Sides of Quantum Technology, a blog with the goal of educating individuals on the current state of quantum computing and quantum telecommunications. This blog was created in response to the growing interest in these two areas by individuals who are not well versed in quantum mechanics or computer science, but want to learn more about the future of these technologies. We aim to provide you with the information you need to understand the basics behind these two sides of quantum technology and how they may affect your future. Our first post will be a general introduction to quantum computing and what we can expect from it’s applications, followed by an introduction to quantum teleportation and how it is expected to revolutionize our communication networks. If you have any questions or comments, feel free to contact us!
Quantum Computing and Quantum Telecommunications are two sides of the same coin. Without Quantum Computing, there would be no Quantum Teleportation (which is not what the term sounds like, but I’ll get to that later).
Telecommunications is the transfer of information from one place to another. This can be a simple as a person talking face-to-face in real time, or as complex as a person using a computer to send an email halfway around the world to another person who also uses a computer.
Quantum Computers will eventually be able to create and transmit data at rates that are faster than light. This is currently impossible for normal computers because conventional communication methods only allow for data transfer at speeds equal to or less than that of light.
In theory you could build a quantum computer with a classical network interface and use it over any conventional network connection – even an old-fashioned dial-up modem – but in practice this isn’t possible because quantum states decay so quickly at room temperature that they would be completely destroyed before they reached their destination (and thus become useless).
The term “Quantum Technology” is used to describe the current range of quantum related technologies including quantum communication, quantum sensors and quantum computer technology. The term itself has been used for some time but appears to have come into common usage in the last few years with the rapid growth in popularity of the field.
The term can be confusing as it implies that there is one technology. However, research groups around the world are working on many different types of quantum technology across a broad range of disciplines including quantum information, optics, atomic physics, condensed matter physics and so on. There are essentially two main types of Quantum Technology being pursued at the moment:
Quantum Telecommunication:
Quantum Computing:
These two technologies are very different in nature and approach. Despite recent advances in both fields they also remain at very early stages of development – especially from an industrial point of view. It may be some time before any commercial applications exist for either type of quantum technology. This site will examine both telecommunication and computing within the wider context of Quantum Technology & Information Theory in general.
Quantum computing is the future of computation. It is only a matter of time before the first universal quantum computer will be built, and we don’t have to wait for that to happen to realize the benefits of quantum technology. Quantum mechanics already plays a significant role in our daily lives through the use of quantum devices that enable us to communicate securely over long distances.
When people hear about “quantum technology” they are often thinking about quantum computing. This is understandable: there is no doubt that quantum computers will be just as revolutionary for the world as classical computers were once they reach our daily lives; but we don’t need to wait until then to start using products and services based on quantum mechanics.
Quantum cryptography and telecommunications use the same principles that make quantum computers so special – namely, entanglement and superposition – without having to build a full-fledged quantum computer. A small-scale device can do the job just fine.
In fact, some companies have already started offering commercial products based on these principles, such as ID Quantique in Switzerland or Quintessence Labs in Australia. As far as I know, these are mostly encryption devices designed for banks and other government agencies. I haven’t come across any consumer products yet, but I’m sure they will
(This is a post from the old blog, which I have decided to keep for archival purposes. The post was written by Craig Gidney, and is reproduced here with permission.)
I talk about quantum communications here all the time. But most of the time when people think about “quantum technology”, they think about quantum computers. So I want to give a little overview of where quantum computing stands today, and what some of the major challenges are in building a large-scale quantum computer.
Quantum Computers vs. Classical Computers
A classical computer works by having bits, each of which can be either 0 or 1. You can perform operations on these bits that change their values (usually through logic gates or something equivalent). Quantum computers work in a very similar way; however their “bits” are called qubits and can be both 0 and 1 at the same time (i.e., they are in a superposition of 0 and 1). This lets you do some interesting things, like performing an operation on every possible input to your program simultaneously.
The first thing that people notice about this is that it means you could just put your problem into a quantum computer, wait for it to output your solution, and then read off what the answer was
The first thing to notice about a quantum computer is that it has all the properties of a classical computer. It can perform any calculation that a classical computer can. It can store information, move information around, and process information. The difference is in how it stores and moves information.
A classical computer represents information as bits. A bit is either 0 or 1. Information is stored in a sequence of bits, and is moved around as a sequence of bits.
A quantum computer represents information as qubits (quantum bits). A qubit has both a 0 state AND a 1 state at the same time… until it’s observed, at which point it becomes either 0 or 1. Until observed, it’s both 0 and 1 simultaneously. This allows for some fundamentally new behavior – like superposition, which we’ll get to in a moment – but for now let’s just focus on how qubits are stored and moved around in memory and between computers. A sequence of qubits isn’t just one bit after another; it’s both states at once: 00011011… etc…
This means that you can’t simply send qubits from place to place over wires like you do with classical bits; they are too fragile. Instead, you have to use photons (
The internet is a great example of quantum communication technology. The principle behind it is called entanglement, which allows two particles to be linked together so that they share a history even when they are apart. Even though these particles are separated by long distances, they continue to interact with each other in an intimate way.
This is the foundation of quantum communication technology. As we learn more about the nature of this phenomenon, we can use it to develop better ways of communicating across large distances.
Quantum computers are another example of this type of technology. In a quantum computer, information is stored in the form of a superposition of states. These states can exist simultaneously, and each one represents a possible outcome from a calculation. This means that instead of just having one possible result from a calculation, you have many possible results at once!
Quantum computers are different from traditional computers because they operate on the principle of superposition instead of linearity. This means that there are no limits to what you can do with them!
If you’ve ever wondered how scientists create new materials or do other amazing things with physics, then this is how they do it: by using quantum physics as their toolbox.