diff --git a/2.typ b/2.typ index 34e2bea..90c6b46 100644 --- a/2.typ +++ b/2.typ @@ -811,7 +811,10 @@ where $bb(L)_!(A,B) := bb(L)(!A, B)$ ] #exercise[ - Prove this defines a category : + Prove this defines a category. +] + +#solution[ - Identity is $epsilon$ - $f << epsilon_A = f compose !epsilon_A compose eta_A = f$ - $epsilon_B << f = epsilon_B compose !f compose eta_A = f compose epsilon_(!A) compose eta_A = f$ @@ -845,3 +848,66 @@ where $bb(L)_!(A,B) := bb(L)(!A, B)$ edge((0, 0), (0, 1), [$nu_A$], label-side: right, "->") })) ] + +=== The Seely isomorphisms + +Let $A, B in Ob(LL)$. Assue the cartesian product $A \& B$ exists in $LL$. + +$V$ is the right adjoint $=>$ preserves limits. + +$V ( A \& B ) tilde.eq V A times V B$ + +$L$ is strongly monoidal so $L (V A times V B) tilde.eq underbrace(L V A, !A) (*) underbrace(L V B, !B)$ + +So $underbrace(L V (A \& B), !(A \& B)) tilde.eq L V A (*) L V B tilde.eq !A (*) !B$ + +Similarly, if $LL$ has a terminal object $top$, $!top tilde.eq 1$. + +== A model of Linear Logic : Probabilistic coherence spaces + +#definition(subtitle: [Duality in $RR^X_+$])[ + Let $X$ be a countable set : + - For all $x in X$, define $Pi_x : cases(RR^X_+ -> RR_+, a space t-> space a_x)$ + + define $e_x in RR^X_+$ by $pi_x(e_x) = 1$ + - For all $a, b in RR^X_+$, let $a ⋅ b = sum_(x in X) a_x b_x in [0, +infinity[]$ + - For all $P subset.eq RR^X_+$, let + $ + P^bot = { b in RR^X_+; forall a in P, underbrace((a⋅b <= 1), R(A, b)) } subset.eq RR^X_+ + $ + In particular $P^(bot bot) subset.eq P$ +] + +#definition([ + A probabilistic coherent space is a pair + $X = (|X|, P X)$ where $|X|$ is a countable set, and $P X subset.eq RR^(|X|)_+$ such that + - $P X ^(bot bot) = P X$ (equivalent to $P X ^(bot bot) subset.eq P X$) + - $forall x in |X|$, + - $exists lambda > 0, lambda e_X in P X$ + - $exists lambda > 0, lambda e_x in P X ^bot$ +]) + + +#example[ + $ + ({*}, [0, 1]) &=: 1\ + &=: bot\ + (emptyset, {0}) &=: top\ + &=: 0\ + (|X|, [0, 1]^(|X|))\ + ({0, 1}, ([0, 1]^2)^bot &= {binom(x, y) | (binom(1, 1) dot binom(x, y)) = x + y <= 1 }) \ + $ + Given $X = (|X|, P X)$ a pcoh, + $X^bot := (|X|, P X^bot)$ is a pcoh. +] + +#definition([ + Let $X, Y$ be pcohs. + A _linear morphism_ from $X$ to $Y$ is a map \ + #align(center)[$f in "Set"(P X, P Y)$] + such that there exists a (necessarily unique) matrix $tilde(f) in RR^(|X| times |Y|)_+$ such that + for all $a in P X$, \ + #align(center)[$f(a) = (sum_(x in X) tilde(f)_(x,y) a_x)_(y in |Y|)$] + pcohs and linear morphisms form a category PCoh. +]) + diff --git a/README.md b/README.md new file mode 100644 index 0000000..703e563 --- /dev/null +++ b/README.md @@ -0,0 +1,9 @@ += SEMPL + +Ce dépôt contient mes notes de SEMPL (_Models of Programming Languages: +Domains, Categories, Games_). + +Je ne peux garantir l'absence de typos et d'erreurs de recopiage. + +- `1.typ` : Contient la partie 1 de Paul-André Mellies +- `2.typ` : Contient la partie 2 de Guillaume Geoffroy