Thomasina

Valentine, using his computer to extrapolate Thomasina's ideas, relates them to the concept of entropy ; he wonders whether Thomasina or Septimus was the genius behind the theories.

Singer and actor Thomasina Petrus has been likened to Billie Holiday, whose voice she easily channels, but with more light and sunshine.

A graduate student of mathematics, he pores over several old documents and comes to acknowledge Thomasina's genius.

As their studies unfold – with the help of Valentine Coverly, a post-graduate student in mathematical biology – the truth about what happened in Thomasina's time is gradually revealed.

Both his parents, Georg Iserin and Thomasina de Porris, possessed considerable wealth, his father being the town physician.

Chloe reads a newspaper report on the Byron murder theory and then talks about determinism with Valentine, echoing the discussion between Septimus and Thomasina.

Hannah and Valentine mention that Thomasina died in a fire on the eve of her seventeenth birthday.

Lady Croom enters, complaining to Noakes about the noise of his steam engine ; Thomasina notes that the machine obeys the laws of entropy (which have not yet been formalized ), which describe the universe as winding down.

Scene 4 Hannah rediscovers Thomasina's primer containing her ideas on iteration and chaos theory ; this recalls Septimus' assertion that what was lost is eventually rediscovered.

She has found two letters Septimus wrote in case he should die in the duel: one to Thomasina, is about rice pudding, and the other is a love letter addressed to herself.

Then landscape architect Richard Noakes enters, shortly accompanied by Captain Brice and Lady Croom; the three discuss proposed modifications to the gardens, while Thomasina sketches an imaginary hermit on Noakes's technical drawing of the garden.

Thomasina drily comments, "Yes Mama, if you would have it so".

Thomasina's insights into thermodynamics and heat transfer, and the idea that the universe is cooling, echo the poem Darkness by her "real life" contemporary, Lord Byron.

Thomasina starts asking why jam mixed in rice pudding can never be unstirred, which leads her on to the topic of determinism and to a beginning theory about chaotic shapes in nature.

While Septimus awaits appropriate music for Thomasina's dance lesson, he examines the sketch she made to illustrate the irreversibility of heat ; his action mirrors that of Hannah and Valentine, who also pondered the same diagram.

While teaching Thomasina, he works on his own research and has affairs with the older women of the house.