The mass ratio of protons and electrons is deemed to be a universal constant. And rightly so, as the latest radio-astronomy observations of a distant galaxy have shown. Scientists used the 100-metre radio telescope in Effelsberg to measure absorption lines of the methanol molecule at a number of characteristic frequencies. The researchers analysed the spectrum of the simplest of all the alcohols ...

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Passing the alcohol test: Fundamental properties of molecules have not changed during the past seven billion years