Welcome to What Does a Quantum Physicist Do? This blog is dedicated to the question “What does a quantum physicist do?” and I hope that it will provide some interesting insights into the world of experimental quantum physics.
I am an experimental quantum physicist working at the University of Queensland School of Mathematics and Physics with Prof. Andrew White and Dr. Warwick Bowen developing techniques for ultra-cold atom interferometry. Previously I was a PhD student at the University of Science and Technology of China under the supervision of Prof. Jianming Zhao, where I studied using ultra-cold atoms as optical frequency references. So if you have any questions about what a quantum physicist does please ask!
What does a quantum physicist do?
The answer is: she works on things that are really small. So small, in fact, that you can’t see them with a microscope. They’re just too tiny. You can’t see them with any kind of light either — even if you shine the brightest light you can think of on them, they will still be invisible to your eyes. Why? Because they’re just too small!
So what exactly do we work on, if we can’t look at it? How do we study something we can’t see? And how do we know what it is if we can’t see it?
We work with models. We make models of things that are much to small to see, and then we study those models and learn about the real thing. Mostly, our models are mathematical — that means that instead of making a clay model or painting a picture of our tiny things, we write equations about them. An equation is like a recipe for a cake — it tells us the ingredients and how to put them together. But instead of telling us how to bake a cake, the equations tell us how our tiny objects behave (do they bounce when they hit each other or stick together?) or what properties they have (how big or
I spend a lot of time thinking about quantum physics. I also spend a lot of time explaining it to people who want to learn more about it. But in all those many hours, I rarely come across the question that seems to me the most interesting question about quantum physics: what does a quantum physicist actually do?
I know some physicists who work purely on theory, trying to develop new models or understand existing ones. These people tend to be less accessible, even if they are very smart and friendly individuals. A lot of their work consists of abstract mathematical manipulations, which can make it challenging to explain their research clearly and without jargon.
I also know some physicists who work purely on experiment, assembling apparatus and collecting data. These people tend to be more accessible because they work on real objects you can see and touch. Their work is often exciting because they get unexpected results and have to figure out what’s going on.
But I don’t think this gives a complete picture of what physicists actually do in practice. Most of the physicists I know (including myself) do both experiment and theory, at least some of the time. In fact, that’s one reason why I like physics: it’s a field where you can get your hands dirty playing around with real-world
Once upon a time, quantum physics was the concern of quantum physicists. In recent years, however, the field has emerged from its ivory tower and become a source of commercial technology. The problem is that few people have any idea what the field consists of.
A few weeks ago, for example, I wrote about D-Wave Systems, a Canadian company that claims to have built a machine that uses quantum mechanics to dramatically speed up certain computations. This claim is controversial, with many experts arguing that the machine’s speedup is an illusion. In response to my article, I received several interesting e-mails from readers. One read as follows:
I am very familiar with the theory of qubits and how they may be manipulated such that they can perform calculations at rates approaching infinity (at least when compared to standard computer chips) but I was wondering if you might be able to tell me what exactly a “quantum physicist” does? Is it just someone who works in theoretical physics or is there something more specific?
I asked this question because it seems like there are a lot of “quantum physicists” involved with the D-Wave project and I was wondering if these are simply theoretical physicists or if there are other qualifications that one must meet in order to call themselves
I am a theoretical physicist. That means I like to think about stuff and solve problems, but I don’t really do experiments (a lot of my friends do).
People often ask me what I do. To explain that, I need some other words first.
I work in quantum technology. You may have heard of quantum computing or quantum cryptography, or maybe something about superposition and Schrödinger’s cat?
In a nutshell, quantum technology is the science of using the laws of quantum mechanics for applications. Usually we are talking about using the properties of single atoms to build things for us. Things like computers and communication devices that use light instead of wires or transistors which are smaller than viruses. People like me try to figure out how such devices would work and if they are possible at all. We look at the physics behind it and try to come up with new ideas how they can be made practical.
There are many different jobs in physics, and this diversity has been increasing rapidly in recent years. But to say that there is only one job in physics would not be inaccurate. The job of the physicist is to make sense of nature by following the trail where ever it leads.
The conceptual framework physicists follow is called quantum mechanics. This framework is used by physicists to describe the behavior of matter at a fundamental level. There are some phenomena that can be described by analogies to other situations or by common sense reasoning, but we also have many observations for which we have no good explanation. These observations beggar belief. They violate our intuition about what should happen and why. They force us to question our assumptions about the world around us, and they defy easy explanation.
Quantum mechanics does not solve these puzzles because it has an elegant mathematical structure or because it was derived from experiment. It solves them because it works, because when you use its equations you get reliable predictions that agree with experiment and observation. Quantum mechanics makes sense of nature so well that it is now used routinely to make accurate predictions in fields as diverse as chemistry, materials science and cosmology.
Today I am giving a public lecture on quantum physics at the University of York. This would be an exciting thing to do in itself, but it is particularly exciting because I have written the talk in the style of a stand-up comedy routine.
I hope this will get people excited about physics and see that physicists are not boring geeks with no social skills – though some of us are, most are not!
The idea came from a conversation with a friend who does stand-up comedy for a living. She said that I should try stand-up as a way to get more people interested in physics. That’s because most people think that physicists are boring – we just sit around talking about equations, and we don’t care about anything real.
So, instead of writing a “proper” talk, I decided to write something that was more like a comedy routine than a science lecture. This turned out to be harder than I thought it would be! Good comedy routines require several jokes per minute, and it is really hard to make jokes about quantum physics.
For example, one of my jokes goes like this: “You know what they say: there’s no such thing as perfect security… apart from quantum cryptography