Weak measurements have thus far been considered instrumental in the so-called
direct measurement of the quantum wavefunction [Nature (London) 474, 188
(2011)]. Here we show that direct measurement of the wavefunction can be
obtained by using measurements of arbitrary strength. In particular, in the
case of strong measurements, i.e. those in which the coupling between the
system and the measuring apparatus is maximum, we compared the precision and
the accuracy of the two methods, by showing that strong measurements outperform
weak measurements in both for arbitrary quantum states in most cases. We also
give the exact expression of the difference between the reconstructed and
original wavefunctions obtained by the weak measurement approach: this will
allow to define the range of applicability of such method.Comment: Updated version, 5 pages + Supplementary Informatio
