Number 33, May 8, 1991 by Phillip F. Schewe and Ben Stein
LIQUID-CRYSTAL COSMOLOGY. Speaking at the recent APS meeting in Washington, Isaac Chuang and Bernard Yurke (201-582-4961) of AT&T Bell Labs and Neil Turok of Princeton described an experiment in which they compared the behavior of a liquid crystal and the presumed behavior of matter in the early universe. Cooling and squeezing the crystal caused the constituent rodlike molecules to undergo a phase transition into a more ordered state. This symmetry breaking brought with it various imperfections in the liquid crystal which Yurke refers to as monopoles, strings, walls, and textures in analogy with similar "defects" believed to exist in the fabric of the evolving universe. Over time, the liquid-liquid defects exhibit self-similarity: the pattern of defects is similar on a variety of size scales. The universe itself, some cosmologists believe, may have this property. (Science, 3 May 1991.)
THE FY92 FEDERAL BUDGET request for civilian R&D includes a rise of 10% over last year, from $26.3 billion up to $28.8 billion, while military R&D would rise by 15%, from $37.8 billion up to $43.2 billion. Selected physics budget request items for DOE include (in millions) $666.4 for high-energy physics, $533.7 for the SSC, $342.4 for nuclear physics, $714.7 for basic energy science, $337.1 for magnetic fusion, and $182.5 for inertial fusion. At the NSF, the total mathematical and physical sciences budget of $650.1 million includes (in millions) $142 for physics, $136.6 for materials, and $107.4 for astronomy. (Physics Today, April 1991.)
THE SLOWEST PROCESS OBSERVABLE IN NATURE , with a lifetime between 1019 and 1021 years, is double beta decay. In this rare phenomenon two neutrons inside a nucleus decay simultaneously into a pair of protons along with two electrons and two antineutrinos. Observed for the first time a few years ago in selenium-82, double beta decay has now been seen also in germanium-76- and molybdenum-100. (CERN Courier, April 1991.)
ALPHA CENTAURI , the Sun's nearest neighbor, seems to have many of the properties necessary for fostering life. Alpha Centauri A, the biggest of the three stars that make up the stellar system, is a lot like our local star: they are both classified as a G2-type star (neither too hot nor too cold for life). This criterion alone rules out most stars in our galaxy, including red dwarfs (70% of the stars in the Milky Way) and white dwarfs (10%). Alpha Centauri A is also, like our Sun, stable (it wouldn't fry and then freeze life), old enough (intelligent life took 4.6 billion years to evolve on Earth), and metal rich (metals, in this case meaning any element heavier than helium, are necessary for life.) The celestial mechanics of three Alpha Centauri stars is such that small rocky planets could form, but it is more difficult to say whether any of them would be warm and watery enough to support life. (Astronomy, April 1991.)
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