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The direct detection of gravitational waves in 2015 [1] was among the most important discoveries in fundamental physics in recent decades and a proof of one of the fundamental predictions of General Relativity (GR). The signal was observed by the two underground LIGO detectors in Hanford and in Livingston (Fig. 1); the comparison of the data in the bottom plot demonstrates that both detectors witnessed the same event. At least two detectors operating simultaneously are needed to confirm the detection because these instruments are so sensitive that various noises might contaminate the signal, such as seismic activities or even animals walking on the ground above the detector. In addition, it is very important that the observed signal matches the theoretical prediction very well. This is a confirmation that the observed gravitational wave event is a merger of two compact objects with spacetime curvature in their vicinity reaching extreme values. Even though a number of exotic scenarios cannot be excluded, the most probable one is that these were two colliding black holes. (...)

The year 1676 was very important for humanity, be­cause Antoni van Leeuwenhoek discovered the empire of bacteria. He called these small creatures animalcula (small animals). His discovery was a milestone in our civilization for at least two reasons: He discovered creatures invisible to us which have been killing humans for thousands of years, often responsible for millions of deaths in one year. While Antoni van Leeuwenhoek did not know that bacteria could be dangerous for humans, his followers like Louis Pasteur, Robert Koch and other „microbe hunters“ realized the danger coming from these tiny creatures and also developed weapons against this empire [1].

Van Leeuwenhoek was the first human who looked at short distance scales invisible to us and discovered thereby a new underground world. At that time, researchers looked mainly at large distances, discovering new planets and find­ing laws, such as the Kepler laws which Isaac Newton was able to derive from his mechanics. (...)

The nature and properties of Dark Matter are largely unknown: proposed candidates span tens of orders of magnitude in mass, ranging from elementary particles infinitesimally lighter than electrons to massive primordial black holes [1]. One of the most compelling candidates is a new class of subatomic particles: weakly interacting massive particles (WIMPs). WIMPs represent the current paradigm for searches for Dark Matter particles. They are up to a hundred times heavier than protons and only interact weakly with ordinary particles. Presumably, they were produced in the early universe.

To understand Dark Matter is a multi-disciplinary effort involving different and complementary experimental techniques. Direct searches rely on the distribution of Dark Matter in the Milky Way exposing the Earth to a constant high flux of Dark Matter particles. Direct detection experiments aim to detect their elastic scattering off nuclei in specialised low background detectors. Indirect searches are based on the annihilations or decays of Dark Matter particles in astrophysical systems. Various ground and space-based specialised instruments monitor the frequency of such events. Collisions in high-energy particle accelerators like the Large Hadron Collider (LHC) might create particles which were present in the early universe. (...)

The aim of nonequilibrium statistical mechanics is to understand the properties of matter outside of equilibrium, starting from microscopic dynamics. At this time nonequilibrium statistical mechanics of transport phenomena close to equilibrium is a well-developed physical theory (due to the work of Onsager, Green, Kubo, etc. in the 1950’s, see for instance [1]). Away from this area, the theory of nonequilibrium is a program, or a variety of programs, rather than a theory. Here I shall make a choice, and describe an approach starting with classical Hamiltonian microscopic dynamics. From my point of view this approach has the interest that it uses nontrivial recent results in the theory of smooth dynamical systems, and that it sheds light on interesting physical phenomena: heat transport, hydrodynamic turbulence, and life. (...)