Considering a free energy F(m) with m = (momx, Smy). Here mo is the position of...

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Considering a free energy F(m) with m = (momx, Smy). Here mo is the position of the minimum of F, i.e. F(mo) is the minimum, while dmx, Smy are deviations from the minimum position. (a) What does mo correspond to physically? = (b) What does the curvature of F in the directions of Sm and my correspond to physically? (c) Relatedly, given the free energy F(8mx, Smy) = a|T Tc|8m + b|T Tc|6m with a, b0, how do the excitation gaps for 5mx and my dependent on |T - Te|? In each case, what is the value of the exponent, n, whereby the excitation gap A is written as A ~ |T - T|". In the ordered phase (say, T < Tc), what is the physical picture of (low-energy) excitations in terms of the direction/angle of m? Considering a free energy F(m) with m = (momx, Smy). Here mo is the position of the minimum of F, i.e. F(mo) is the minimum, while dmx, Smy are deviations from the minimum position. (a) What does mo correspond to physically? = (b) What does the curvature of F in the directions of Sm and my correspond to physically? (c) Relatedly, given the free energy F(8mx, Smy) = a|T Tc|8m + b|T Tc|6m with a, b0, how do the excitation gaps for 5mx and my dependent on |T - Te|? In each case, what is the value of the exponent, n, whereby the excitation gap A is written as A ~ |T - T|". In the ordered phase (say, T < Tc), what is the physical picture of (low-energy) excitations in terms of the direction/angle of m?