Nobel Lecture: Superfluid ${}^3\mathrm{He}$: the early days as seen by a theorist^*

Figure 1

The phase diagram of liquid ${}^3\mathrm{He}$ at melting pressure below $3\mathrm{mK}$.

Figure 2

The behavior of the NMR resonance frequency ${\omega }_{\mathrm{res}}$ in liquid ${}^3\mathrm{He}$ below $3\mathrm{mK}$. (The qualitative behavior of the static susceptibility $\chi$ is also noted.)

Figure 3

A comparison between ferrromagnetism and spontaneously broken spin-orbit symmetry.