Complex sentence: Grau and Kleen (1982) and Kleen (1986), argued that the Johnson noise of a resistor connected to an antenna must satisfy Planck's thermal radiation formulaa, thus the noise must be zero at zero temperature and FDT must be invalid.
Split into simpler sentences: Grau and Kleen (1982) and Kleen (1986), argued that the Johnson noise of a resistor connected to an antenna must satisfy Planck's thermal radiation formula. Thus the noise must be zero at zero temperature and FDT must be invalid.