From Andrew Taubman, Sydney, Australia
Anil Ananthaswamy reports that two different ways of measuring the present-day expansion of the universe produce different values of the Hubble constant (20 July, p 34). This brings to mind the principle that measurement changes the phenomenon observed at the quantum scale.
The current mess of string theory suggests this may be happening on a cosmic scale. Every time we approach an explanation, the universe confounds us with another inexplicable twist. Some entities just don’t like being understood!
