It is a well-known fact in quantum physics that the position and momentum of an object (e.g., a single atom or a vibrating mirror) cannot be known with an arbitrary precision. The more we know about the position of a mirror, the less we know about how fast it is moving and vice versa. This… Continue reading How well can we measure position?

# Blog

## Seeing ripples in spacetime

One hundred years after Albert Einstein shared it with the world, the general relativity is waiting for its last confirmation: direct observation of gravitational waves. These ripples in the curvature of spacetime are created when a massive object accelerates. Typical examples of such systems are binary neutron stars or black holes; as the two stars (or… Continue reading Seeing ripples in spacetime

## Connecting superconducting quantum computers with light

Entanglement is a peculiar feature of quantum systems that makes them behave as if they were sitting directly next to each other even if they are kilometres away. Such behaviour does not occur in classical physics. Classical particles can affect each other through fields -- such as the gravitational or electromagnetic field -- but these fields propagate with… Continue reading Connecting superconducting quantum computers with light

## Through the looking glass

One of the things I love about physics is how it changes the way one sees the world. As one starts to think about some basic things very differently. Then even such a simple act as measurement is a complicated process which can even be used to manipulate physical systems.

## A new start

I am at the point in my PhD where I am truly becoming a researcher and am no longer just a student. How can I tell? I just finished a project I worked on basically since I started my studies more than two years ago. It was my supervisor's idea to study this particular problem,… Continue reading A new start

## The joys of theoretical physics

Have you always thought mathematics is dull and complicated? You are certainly not alone. But there is a lot of beauty hidden in it and in the way it describes our world. Theoretical physics is all about using maths to describe nature. As the universe we live in is vast and filled with myriads of… Continue reading The joys of theoretical physics

## How to measure time

Precise timekeeping is crucial for many of our daily activities. High-speed communication (on the internet or in a mobile phone network), satellite navigation, and many other tasks require time synchronisation over long distances to work properly. But how is time measured? And can quantum physics help reach better accuracies? The basic idea behind measuring time is… Continue reading How to measure time

## New page on the basics of quantum physics

Do you have absolutely no knowledge about quantum physics? Do you want to get at least a basic understanding about what it is, why it is important, or how it can be relevant to everyday life? I just added a new page that tries to explain some of these basic questions in (I hope) an… Continue reading New page on the basics of quantum physics

## Simplifying quantum systems

claimtoken-552906769c445 I already talked about using measurements and feedback in quantum physics and how these tools can be used to prepare interesting quantum states. But it is not an easy task -- experimental realisations require ultrafast electronics to apply feedback in real time. And theoretical analyses? Those are not easy either. Take a simple example -- an… Continue reading Simplifying quantum systems

## Building the quantum internet

Do you remember your first computer? And your first internet connection? Sure, they were not as powerful as today's technology but it was something completely new and opened many possibilities. A quantum computer, ideally connected to quantum internet, must then be even more remarkable. Although it is true that algorithms for quantum computers focus on… Continue reading Building the quantum internet