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Offers reflection on physicist Richard Feynman, as part of a special issue of "Physics Today" dedicated to his memory, written by one of his colleagues at the California Institute of Technology. Description of Feynman as energetic, full of vitality, and playful; Suggestion that he would be competitive and vain at time; Discussion of some of Feyman's early discoveries in quantum theory; Importance to Feynman of "being different"; Comments on quantum cosmology.

Discusses Mount Wilson Observatory diffraction gratings. Details of how engines capable of ruling hundreds of thousands of straight, parallel, equally spaced grooves within tolerances of only a few angstroms, have led to advances in fields as different as quantum mechanics and astrophysics; Details of how gratings and prisms work; Different type of ruling engines; Technological advances at the Mount Wilson Observatory. INSET: Distribution of gratings..

The author comments on the use of X-ray free-electron laser (FEL) at a photon energy with 849 electronvolts which was demonstrated by N. Rohringer and colleagues at the SLAC National Accelerator Laboratory in Menlo Park, California.The author mentions that the researchers' experiment was able to focus on Linac Coherent Light Source (LCLS) X-ray pulses. Moreover, the author notes the important property of the X-ray pulses which resulted from the quantum mechanics' rules.

The article focuses on the experiment conducted by Nadav Katz with his colleagues at the University of California, Barbara, that is aimed at reversing the transition from quantum realm collapse to the classical reality observable in matter. It notes that the team created a phase qubit that is made up of fluctuations in the average current flowing around the loop with both high and low energies. The team was able to find out the possibility of returning a collapse state to its original uncollapsed form by performing multiple runs of the experiment.

The article reports that an international team of researchers at the High Energy Accelerator Research Organization (KEK), has announced their measurement of an anomalous asymmetry in the decay rates of exotic particles known as B mesons in Japan. Combined with the measurements from BaBar collaboration, a similar experiment at the Stanford Linear Accelerator Center (SLAC) in Menlo Park, California, the new finding offers a glimpse of a possible new source for a very fundamental asymmetry which is the dominance of matter over antimatter in the universe.

Presents information on the physics professors who were awarded at the 129th national meeting of the American Association of Physics Teachers in Sacramento, California in July 2004. Contributions of Anton Zeilinger to research on quantum theory; Areas where Kenneth S. Krane distinguishes himself as a physicist; Focus of Robert W. Brown's career.

Hydrogen peroxide (H(2)O(2)) photochemical production was measured in bulk and size-fractionated surf zone and source waters (Orange County, California, USA). Post-irradiation (60 min; 300 W ozone-free xenon lamp), maximum H(2)O(2) concentrations were approximately 10000 nM (source) and approximately 1500 nM (surf zone). Average initial hydrogen peroxide production rates (HPPR) were higher in bulk source waters (11+/-7.0 nM s(-1)) than the surf zone (2.5+/-1 nM s(-1)). A linear relationship was observed between non-purgeable dissolved organic carbon and absorbance coefficient (m(-1) (300 nm)). HPPR increased with increasing absorbance coefficient for bulk and size-fractionated source waters, consistent with photochemical production from CDOM. However, HPPR varied significantly (5x) for surf zone samples with the same absorbance coefficients, even though optical properties suggested CDOM from salt marsh source waters dominates the surf zone. To compare samples with varying CDOM levels, apparent quantum yields (Phi) for H(2)O(2) photochemical production were calculated. Source waters showed no significant difference in Phi between bulk, large (>1000 Da (>1 kDa)) and small (<1 kDa) size fractions, suggesting H(2)O(2) production efficiency is homogeneously distributed across CDOM size. However, surf zone waters had significantly higher Phi than source (bulk 0.086+/-0.04 vs. 0.034+/-0.013; <1 kDa 0.183+/-0.012 vs. 0.027+/-0.018; >1 kDa 0.151+/-0.090 vs. 0.016+/-0.009), suggesting additional production from non-CDOM sources. H(2)O(2) photochemical production was significant for intertidal beach sand and senescent kelp (sunlight; approximately 42 nM h(-1) vs. approximately 5 nM h(-1)), on the order of CDOM production rates previously measured in coastal and oceanic waters. This is the first study of H(2)O(2) photochemical production in size-fractionated coastal waters showing significant production from non-CDOM sources in the surf zone.