A lifelong quantum quest

John Wheeler’s work over his entire working life coming under the broad heading of quantum mechanics is described — it ranges over very practical issues relating to atomic and nuclear physics (particularly nuclear fission), a far-reaching conceptual framework such as the scattering matrix, and deep foundational issues. His inspiration enabled his students to make outstanding contributions as well.     

Changes in biochemical constituents and induction of early sprouting by triadimefon treatment in white yam （Dioscorea rotundata Poir.） tubers during storage

The ability of triadimefon(TDM),a triazolic fungicide,to alter the biochemical constituents and thereby minimizing the days required for sprouting in white yam(Dioscorea rotundata Poir.) tubers during storage under(30±2) °C in the dark,was studied.TDM at 20 mg/L was given to tubers by dipping the tubers in treatment solution containing 20 mg/L TDM on 10,25 and 40 d after storage(DAS).Starch,sugars,protein,amino acid contents as well as protease and α-amylase activities were estimated on 15,30 and 45 DAS from two physiological regions viz.,apical and basal regions of the tubers.In normal conditions(control) sprouting occurred on 70 to 80 DAS.The starch content decreased,while protein,amino acid,sugar contents and protease and α-amylase activities were increased due to TDM treatment and led to early sprouting.     

The Bondi Approach to the Lorentz

This article summarises a very elegant way of teaching the Lorentz transformation, which was introduced by Hermann Bondi (see Resonance, March 2016 for more about him). The starting point of this approach is that the best way of assigning space and time coordinates to a distant event is by radar, i.e., by transmitting and receiving light signals, and noting the times of departure and arrival. There is no need for the rigid rod. Bondi’s method, which he called the k-calculus, makes good use of the Doppler effect (hence the delta in the title). For students who have learnt special relativity in the standard way, this approach provides a different view of the subject.