Remarks on astrophysical origin of the knee in the cosmic ray spectrum

All astrophysical explanations of the knee in cosmic ray spectrum accept the hypothesis of its existence a priori without any doubt. But, there exist experimental evidence against this hypothesis. Experimental data on the knee in various secondary cosmic ray components obtained by KASCADE array as well as by many other arrays reveal the existence of the knee (Δγ≈0.4÷0.5) in the electromagnetic component (e and γ including Cherenkov light) and the absence of it or a very small knee (Δγ≈0.1÷0.2) in muonic and hadronic components. But, one could expect the inverse relationship in the case of the astrophysical knee origin. A brief review of experimental data concerning this problem is given.