TheFifthHEIDELBERGInternationalConferenceonDarkMatterinAst- and Particle Physics, DARK 2004, took place at Texas A&M University, College Station Texas, USA, October 3-9, 2004. It was, after Cape Town 2002, the second conference of this series held outside Germany. The earlier meetings, starting in 1996, were held in Heidelberg. Dark Matter is still one of the most exciting and central ?elds of ast- physics, particle physics and cosmology. The conference covered, as usual for this series, a large range of topics, theoretical and experimental. Theoretical talks covered SUSY/SUGRA phenomenology, which provides at present a preferred theoretical framework for the existence of cold dark matter. Also included were other possible explanations of dark matter such as SUSY Q balls, exciting New Symmetries, etc. The most important experiments in the underground search for cold and hot dark matter were presented. Talks describing the current experimental dark matter bounds, what might be obtained in the near future, and the reach of future large (i.e. one ton) detectors were given. The potential of future colliders to correlate accelerator physics with dark matter searches was also outlined. Thus the reader will be able to see the present status and future prospects in the search for dark matter. The exciting astronomical evidence for dark matter and corresponding observations concerning the Milky Way's black hole, high-redshift clusters, wakes in dark matter halos were other important topics at the conference.

Dark matter and dark energy are one of the central mysteries in modern physics, although modern astrophysical and cosmological observations and particle physics experiments can and will provide vital clues in uncovering its true nature. The DARK 2009 Conference brought together World's leading researchers in both astrophysics and particle physics, providing an opportunity and platform to present their latest results to the community. The topics covered are wide-ranging, from terrestrial underground experiments to space experimental efforts to search for dark matter, and on the theoretical aspects, from the generating of a fifth family as origin of dark matter, extra dimensions and dark matter to non-standard Wigner classes and dark matter. One of the new highlights was certainly a possible connection between a neutrino mass as observed by nuclear double beta decay and the dark energy. Highly important and relevant in its field, the book presents a vital snapshot of the sometimes seemingly disparate areas of dark matter research and offers an exciting overview of current ideas and future directions.

The Fourth HEIDELBERG International Conference on Dark Matter in Astro and Particle Physics, DARK2002, was held in Cape Town, South Africa, in the period 4-9 February 2002. This majestic natural area was the site of the first conference of this series (hosted since 1996 in Heidelberg) to be held outside of Germany. Dark Matter has become one of the most exciting and central fields of as trophysics, particle physics and cosmology. The conference covered, as usual for this series, a large range of topics, theoretical and experimental. Topics included Astronomical Evidence for Dark Matter, the Cosmic Microwave Background, Supersymmetry, Inflation and Dark Energy, Structure Formation, Hot and Cold Dark Matter, and Ultrahigh Energy Cosmic Rays all of which were represented by experts in the field. It was very nice to see again many of our 'old' friends in Dark Matter here in South Africa. The organizers were very glad to see, in addition to world experts, the new generation here. Many young participants gave very nice professional talks during the conference. We are grateful to John Ellis for doing an incredible job preparing his excellent summary talk during the sessions. Some special interest and intensive discussions were naturally raised by the first announcement of terrestrial evidence for hot dark matter, obtained from neutrino less double beta decay. This now adds to the evidence for cold dark matter which we have from DAM A for several years already, and which remained unchallenged up to now by other experiments.

Die letzten bei den Jahrzehnte haben eine explosive Entwicklung der Teil und Kosmologie erlebt. Die Teilchenphysik erwies chenphysik, Astrophysik sich als ein entscheidendes Mittel zum tieferen Verstandnis des Universums. Das Aufkommen der Theorien der Grossen Vereinigung der Krafte in der Teil chenphysik erlaubte, das fruhe Universum bis zu den fruhesten Zeitpunkten zuruckzuverfolgen. Umgekehrt treten in astrophysikalischen und kosmologi schen Prozessen Energien auf, die man in Beschleunigern auf absehbare oder besser unabsehbare Zeit nicht erreichen kann, und die die Realisierung ei nes Teils der Fulle der exotischen teilchentheoretischen Vorhersagen erlaubt haben konnten: Baryogenese, Inflation, die Produktion exotischer Teilchen - Monopole, kosmische Strings, Axionen und viele andere. Supersymmetri sche Teilchen (Neutralinos) sind Kandidaten fur kalte dunkle Materie, die die soeben der Beobachtung zuganglich gewordene grossraumige Struktur des Universums und ihre Entstehung verstandlich machen konnten. Neutrinos sind Kandidaten fur heisse dunkle Materie. Eigenschaften von Neutrinos be einflussen die Explosion der Supernovae. Astrophysikalische Neutrinoquellen helfen bei der Bestimmung von Neutrino-Eigenschaften, die eine Schlussel funktion fur die Struktur der Elementarteilchen-Theorien einnehmen. Astro physikalisch erzeugte Axionen sondieren das starke CP-Problem der QCD. Es entstand ein neues Forschungsgebiet, die Teilchenastrophysik, in der man von zwei Seiten versucht, einigen der fundamentalen Probleme der modernen Physik naherzukommen. Das enorme Wachstum in diesem Bereich macht es - insbesondere fur den Anfanger auf diesem Gebiet - zunehmend schwieriger, der Entwicklung auf dem Wege uber die Fachliteratur zu folgen."

In the last 20 years the disciplines of particle physics, astrophysics, nuclear physics and cosmology have grown together in an unprecedented way. A brilliant example is nuclear double beta decay, an extremely rare radioactive decay mode, which is one of the most exciting and important fields of research in particle physics at present and the flagship of non-accelerator particle physics.While already discussed in the 1930s, only in the 1980s was it understood that neutrinoless double beta decay can yield information on the Majorana mass of the neutrino, which has an impact on the structure of space-time. Today, double beta decay is indispensable for solving the problem of the neutrino mass spectrum and the structure of the neutrino mass matrix. The potential of double beta decay has also been extended such that it is now one of the most promising tools for probing beyond-the-standard-model particle physics, and gives access to energy scales beyond the potential of future accelerators.This book presents the breathtaking manner in which achievements in particle physics have been made from a nuclear physics process. Consisting of a 150-page highly factual overview of the field of double beta decay and a 1200-page collection of the most important original articles, the book outlines the development of double beta decay research - theoretical and experimental - from its humble beginnings until its most recent achievements, with its revolutionary consequences for the theory of particle physics. It further presents an outlook on the exciting future of the field.