ABSTRACT
Imagine you wake up in the morning and you pour water in the kettle to make tea but, because you either do not have time or simply have forgotten, you do not measure the temperature of the water at the instant of pouring. Then, after about 5 minutes the water has reached its boiling point (of 100°C), and you wonder what was the initial temperature at the time the water was poured in the kettle. This gives rise to the ill-posed backward heat conduction problem (BHCP) for the parabolic heat equation that is investigated in this chapter using various methods based on quasi-reversibility, logarithmic convexity as well as non-local initial-value methods.
