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The AEI 10 m prototype interferometer facility is currently being constructed at the Albert Einstein Institute in Hannover, Germany. It aims to perform experiments for future gravitational wave detectors using advanced techniques. Seismically isolated benches are planned to be interferometrically interconnected and stabilized, forming a low-noise testbed inside a 100 m ultra-high vacuum system. A well-stabilized high-power laser will perform differential position readout of 100 g test masses in a 10 m suspended arm-cavity enhanced Michelson interferometer at the crossover of measurement (shot) noise and back-action (quantum radiation pressure) noise, the so-called Standard Quantum Limit (SQL). Such a sensitivity enables experiments in the highly topical field of macroscopic quantum mechanics. In this article we introduce the experimental facility and describe the methods employed; technical details of subsystems will be covered in future papers. [ABSTRACT FROM AUTHOR]

World science news briefs are presented. The European Commission will finance the development of quantum technology in Europe. The Excellence Initiative in Germany has been extended to continue to provide funding to universities in the country. The Inter-American Court of Human Rights' report on the 2014 disappearance of students in Mexico has been obstructed by the Mexican government.

Abstract: Using high-resolution Fourier transform spectra of mono deuterated formaldehyde (HDCO) recorded in the 5.8-μm spectral range at Giessen (Germany), we carried out an extensive analysis of the strong ν 3 fundamental band (carbonyl stretching mode) at 1724.2676cm−1, starting from results of a previous analysis [J.W.C. Johns, A.R.W. McKellar, J. Mol. Spectrosc. 64 (1977) 327–339]. For this hybrid band (with both A- and B-type transitions) the analysis was pursued up to high rotational quantum numbers. In this way, it was possible to evidence a resonance which perturbs the ν 3 lines for high K a values which is due to the existence of the 2ν 5 and ν 5 + ν 6 dark bands in the same spectral region. In addition a local resonance is perturbing the 31 levels in =8 which is due to a crossing with the 41 energy levels in K a =11. The model used to calculate the energy levels accounts for the observed A- type, B- type C-type Coriolis (and/or) Fermi resonances which couple the 31 and the 5161, 52, and 41 energy levels. However the 41 state is also involved in strong vibration–rotation interactions coupling the {51,61,41} system of resonation states of HDCO [A. Perrin, J.M. Flaud, L. Margulès, J. Demaison, H. Mäder, S. Wörmke, J. Mol. Spectrosc. 216 (2002) 214–224]. Therefore the final energy levels calculation was performed for the {51,61,41,31,52,5161} resonating states and in this way it was possible to reproduce the observed line positions, within their experimental uncertainties. The present work also led to the determination of the intensity ratio of the B- to A-type components of the ν 3 band I A/I B ∼24 band from spectral fittings performed in several parts of the observed spectrum. Finally, using the 5.8μm band intensity available in the literature we generated, for the first time, a list of line parameters (positions and intensities) for the 5.8μm region of HDCO. [Copyright &y& Elsevier]

The Einstein-Rupp experiments were proposed in 1926 to study the wave versus particle nature of light. Einstein presented a theoretical analysis of these experiments to the Berlin Academy together with the results of Rupp, who claimed to have successfully carried them out. However, as the preceding paper shows, this success was the result of scientific fraud. After exploring the interpretation of the experiments, the present paper shows that they were a relevant part of the background to such celebrated contributions to quantum mechanics as Burn's statistical interpretation of the wave function and Heisenberg's uncertainty principle. Yet the Einstein-Rupp experiments have hardly received attention in the literature on the history of quantum mechanics. In part, this is a consequence of self-censorship in the physics community, enforced in the wake of the Rupp affair. Self-censorship among historians of physics may also have played a role. [ABSTRACT FROM AUTHOR]

The dynamics of an atomic few-level system can depend on the phase of driving fields coupled to the atom if certain conditions are satisfied. This is of particular interest to control interference effects, which can alter the system properties considerably. In this article, we discuss the mechanisms of such phase control and interference effects in an atomic three-level system in the Λ configuration, where the upper state spontaneously decays into the two lower states. The lower states are coupled by a driving field, which we treat as quantized. This allows for an interpretation on the single photon level for both the vacuum and the driving field. By analysing the system behaviour for a driving field initially in non-classical states with only a few Fock number states populated, we find that even though the driving field is coupled to the lower states only, it induces a multiplet of upper states. Then interference occurs independently in three-level subsystems in the V configuration, each formed by two adjacent upper states and a single dressed lower state. [ABSTRACT FROM AUTHOR]

This article profiles physicist Hans Bethe. Bethe was born on July 2, 1906 in Strasbourg, France. He obtained his doctorate summa cum laude in 1928 in Munich, Germany with a thesis on electron diffraction in crystals. When World War II broke out in September 1939, he was in the U.S. and had been recognized internationally as one of the outstanding theorists of his generation. He was one of the first theorists to apply group-theoretical methods to quantum mechanical calculations.

This picture show a graphical sketch of the space of quantum field theories in connection with string theory and quantum gravity: it is divided into two regions: the fertile landscape of theories which can be consistently embedded into quantum gravity and the swampland theories, which are inconsistent from the quantum gravity/string theory point of view. (Image on the title page by courtesy of Dr. Eran Palti, Max Planck Institute for Physics, Munich, Germany.) [ABSTRACT FROM AUTHOR]

The article discusses the discovery on the nature of the quantum-to-classical transition. It refers to the analysis conducted by Klaus Hornberger and Johannes Trost of Munich, Germany on the interaction between dideuterium disulfide and helium. It notes that such discovery has been revealed through the transition of a chiral molecule from a superposition of its left-handed and right-handed isomers to the isomers themselves.

The article focuses on a study that uses lasers in the synthesis of molecules. Headed by Gustav Gerber from the University of Wüzburg in Germany, the researchers, in 1998, used the scheme of quantum control to direct the cleaving of an organometallic molecule in gas. The team has also manipulated the chemical bonds in the scheme. They displayed a surface of palladium to carbon monoxide and molecular hydrogen, after which vaporized it with femtosecond pulses of laser light. Comments of other researchers related to the study by Gerber and his team are also presented.

Reports on the Symposium on Quantum Challenges 2001 held on September 6-8, 2001 at the University of Essen in Germany. Highlights of the event; Keynote speakers; Quantum physics activities.

The article reports on the findings of the study related to quantum mechanics led by Fedor Jelezko and Jörg Wrachtrup at the University of Stuttgart in Germany. In their study of plasma polaritons on the surface of a silver nanowire, Jelezko, Wrachtrup and their colleagues found out that plasma polaritons interfered with themselves. The researchers claim that their finding will be uselful especially in the development of quantum networks.

The article reports on sinusoidal modulation in the decay of the heavy nuclear species. This was observed by Yuri Litvino and co-workers at the GSI heavy-ion institute in Darmstadt, Germany. An overview of the process and result of the experiment is discussed. Also presented are the arguments among theorists regarding the neutro-interference explanation of the said experiment.

The article focuses on the statistical technique in distinguishing the relation of causes and effects. According to Guido Nolte of the Fraunhofer FIRST Institute in Berlin, Germany, and his colleagues, a statistical technique called Granger causality can cause faulty assign causality. They depict a new method that relies on how phase differences between the driving and dependent variables alter with the ratio of the number of observations in a statistical category to the total number of observations of their variations.

The article profiles Karl Marx Planck, founder of quantum physics. A German reporter was searching for old church records for the names of Planck's godparents. The reporter unintentionally discovered that Planck's baptismal entry reads as "Karl Ernst Ludwig Marx Planck." It is yet clear whether the pastor improperly recorded his name or whether Planck himself changed it to avoid confusion with the political philosopher. However, any conclusive proof may have gone up when the 1944 bombing raid destroyed Planck's house in Berlin, Germany.

The paper deals with Carl Friedrich von Weizsäcker's position within the philosophy of mind. It turns out that Weizsäcker's ontology is based on an unorthodox conception both in the philosophy of physics and in the philosophy of mind. His quantum information theoretic reductionism is based on a subtle combination of atomism and holism, his philosophy of mind connected to this is a neutral monism, which proposes a bold intertwining of mind, matter, and space.

Carl Friedrich von Weizsäcker's concept of time is deeply based on the asymmetry between past and future, which he considers as a fundamental aspect of Nature. I review these ideas and their philosophical back ground and confront them with a presentation of the concept of time in modern physics. I argue that the observed irreversibility of our world can be understood from fundamental laws which are invariant under time reversal. I conclude with an outlook on the expected theory of quantum gravity.

As I learned in many conversations with Carl Friedrich von Weizsäcker, he saw his place in the history of science deriving from his "Theory of Urs". This theory will establish the unity of science on the basis of quantum bits. Any attempts to find some "fundamental bricks"--of whatever kind--must fail because of the antinomies of atomism. An abstract quantum bit is a structure quantum that cannot be conceived as a particle in space and time. However, it is clear, solely for logical reasons, that a quantum bit is an ultimate and indecomposable entity. Weizsäcker's revolutionary goal was--already 50 years ago--to unite quantum theory with cosmology and, on these grounds, proceed to a theory of elementary particles. The article gives a short overview of Weizsäcker's approach to the unity of physics, ending with a brief summary of what has been achieved in that endeavour up to now.

What are 'interpretations' of quantum theory? What are the differences between Carl Friedrich von Weizsäkcker's approach and contemporary views? The various interpretations of quantum mechanics give diverse answers to questions concerning the relation between measuring process and standard time development, the embedding of quantum objects in space ('wave-particle-dualism'), and the reference of state vectors. Does the wave function describe states in the real world or does it refer to our knowledge about nature? First, some relevant conceptions in Weizsäcker's book The Structure of Physics (Der Aufbau der Physik, 1985) are introduced. In a second step I point out why his approach is not any longer present in contemporary debates. One reason is that Weizsäcker is mainly affected by classical philosophy (Platon, Aristoteles, Kant). He could not esteem the philosophy of science that was developed in the spirit of logical empiricism. So he lost interest in disputes with Anglo-Saxon philosophy of quantum mechanics. Especially his interpretation of probability and his analysis of the collapse of the state function as change in knowledge differ from contemporary standard views. In recent years, however, epistemic interpretations of quantum mechanics are proposed that share some of Weizsäcker's intuitions.

Announces the holding of the Fifth International Conference on Numerical Methods in Fracture Mechanics held on April 1990 in Freiburg, Germany.

The article discusses a debate which unfolded in the early 1950s and 1960s between East German Marxist philosophers and historians of science and West German theologians and scientists. The subject treated was the attitude towards religion of famous physicist Max Planck who had died a few years earlier, in 1947. The article analyses the different positions of the contributors, mainly with a view to developing a categorial framework usable in descriptions and analyses of the religious attitudes of natural scientists. Moreover the different stages of the debate are outlined in order to exhibit their connections to the larger historical context, i.e. the unfolding of the cold war. In the light of this the debate can be regarded as a religious or ideological war, albeit a cold one, on German soil, which fortunately did not escalate into a hot conflict. It ended, as can be illustrated in a late contribution to the debate, with the collapse of the GDR in 1989 or shortly thereafter.

On May 11, 2008 the German biophysicist Professor Fritz-Albert Popp will celebrate his 70th birthday. This is a welcome occasion to pay tribute to the scientific achievements and human qualities of a scientist whose merits as one of the founders of biophotonics and as a pioneer of quantum biophysics increasingly find appreciation internationally.

During the second half of the 19th century Julius von Sachs established the main principles of the photosynthetic production of sugars. From then, a growing number of biochemists and physiologists attended to the process, that appeared like a "black box", in order to detect what came in and what went out of it. The English group of Frederick Blackman gave a remarkable contribution in individuating the close connection between temperature, light and CO2 concentration. Later, the great importance of light was stressed by Otto Warburg, who evaluated the radiant energy necessary to the process in terms of quantum theory. The biochemical mechanism of photosynthesis was interpreted by the main European schools on the basis of Adolf Baeyer's suggestion which posed formaldehyde as the core of the process. Formaldehyde's theory hold engaged the biochemists for about fifty years although some voices rose up against it. However, nobody could put forward more coherent theories until the 1940s, when Sam Ruben and Martin Kamen individuated the cyclic pattern of the process. Ultimately, the first thirty years of the 20th century must be seen as a preliminary stage studded with light and shade even if, in spite of controversial trends, several findings of remarkable interest became to disclose that "black box" as we know today chlorophyll photosynthesis.

All four of the most important figures in the early twentieth-century development of quantum physics-Niels Bohr, Erwin Schroedinger, Werner Heisenberg and Wolfgang Pauli-had strong interests in the traditional mind-brain, or 'hard,' problem. This paper reviews their approach to this problem, showing the influence of Bohr's complementarity thesis, the significance of Schroedinger's small book, 'What is life?,' the updated Platonism of Heisenberg and, perhaps most interesting of all, the interaction of Carl Jung and Wolfgang Pauli in the latter's search for a unification of mind and matter.