Key problems of the flare theory

The basic problems in the solar flare theory are investigated. The possible sources of the solar flare energy are considered and are connected with the strong magnetic fields of the active regions. The experimental and theoretical evidences for the pre-flare accumulation of the magnetic energy in the solar corona in the form of currents running in the solar corona, are pointed out. The configuration of the currents in the corona is discussed and it is concluded that current layers are favoured compared to current filaments. Some arguments are presented favouring the regarding of slowly evolutioning current layers as the pre-flare states. Various instabilities of the current layers resulting in the formation of solar flares are analyzed