Can thermal inflation solve the monopole problem ?
  It is shown that thermal inflation arises naturally in rank greater than five unified theories when non-renormalisable terms are introduced. Thermal inflation is driven by two Higgs fields \Phi_{B-L} and \bar{\Phi}_{B-L} which also break U(1)_{B-L} when acquiring vevs at the end of inflation. The inflationary period provides enough e-foldings to solve the monopole problem for M_{B-L} \geq 10^{12} GeV. We point out that observations suggest that M_{B-L} \simeq 10^{14} GeV. 
R. Jeannerot (University of Sussex)