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?
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.
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
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
When students encounter quantum physics for the first time, it is as simple as it gets -- there are no unwanted interactions, no noise, particles do not get lost. In the real world, nothing is so easy, though. Take a single atom placed in an optical cavity, for instance. (The cavity helps to enhance the… Continue reading How to close an open system