From 93c436ecd633e2f8539aa827d93964d5d5f63dc2 Mon Sep 17 00:00:00 2001 From: kaesle Date: Sat, 28 Dec 2019 18:24:08 -0600 Subject: [PATCH 1/5] Typo fixed in definition right G-action Satisfying (i), require p<|e=p instead of p<|g=p. --- ga/19principal.tex | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ga/19principal.tex b/ga/19principal.tex index f02e481..6f4042f 100644 --- a/ga/19principal.tex +++ b/ga/19principal.tex @@ -49,7 +49,7 @@ \subsection{Lie group actions on a manifold} \ei satisfying \ben[label=\roman*)] -\item $\forall \, p \in M :\ p\racts g = p$; +\item $\forall \, p \in M :\ p\racts e = p$; \item $\forall \, g_1,g_2\in G : \forall \, p\in M : \ p \racts (g_1\bullet g_2) = (p \racts g_1) \racts g_2$. \een \ed From 55367a2d09d3d1d90a77bd768acc58d872c24b57 Mon Sep 17 00:00:00 2001 From: kaesle Date: Sat, 28 Dec 2019 18:36:29 -0600 Subject: [PATCH 2/5] Typo fixed in definition of transitive left G-action Require q=g|>p for some g rather than p=g|>p. --- ga/19principal.tex | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ga/19principal.tex b/ga/19principal.tex index 6f4042f..82b9a2b 100644 --- a/ga/19principal.tex +++ b/ga/19principal.tex @@ -197,7 +197,7 @@ \subsection{Lie group actions on a manifold} A left $G$-action $\lacts\cl G\times M\to M$ is said to be \ben[label=\roman*)] \item \emph{free} if for all $p\in M$, we have $S_p=\{e\}$; -\item \emph{transitive} if for all $p,q\in M$, there exists $g\in G$ such that $p=g\lacts p$. +\item \emph{transitive} if for all $p,q\in M$, there exists $g\in G$ such that $q=g\lacts p$. \een \ed From a2b648a6c4eae89b807744c1a652d1beb8501fac Mon Sep 17 00:00:00 2001 From: kaesle Date: Mon, 30 Dec 2019 09:17:52 -0600 Subject: [PATCH 3/5] Typo fixed in Proposition 19.14. p element of base manifold M rather than of group G. --- ga/19principal.tex | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ga/19principal.tex b/ga/19principal.tex index 82b9a2b..3fae340 100644 --- a/ga/19principal.tex +++ b/ga/19principal.tex @@ -229,7 +229,7 @@ \subsection{Lie group actions on a manifold} \bp If $\lacts\cl G \times M \to M$ is a free action, then \bse -\forall \, p \in G :\ G_p \cong_{\mathrm{diff}} G. +\forall \, p \in M :\ G_p \cong_{\mathrm{diff}} G. \ese \ep From da2d7d5889cf5378295ba4655886c5c9b1b79c88 Mon Sep 17 00:00:00 2001 From: kaesle Date: Mon, 30 Dec 2019 09:18:54 -0600 Subject: [PATCH 4/5] Typos fixed in definition of frame bundle L_pM isomorphic as a Lie Group, not as vector space, to GL(d,R). --- ga/19principal.tex | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/ga/19principal.tex b/ga/19principal.tex index 3fae340..06dec0a 100644 --- a/ga/19principal.tex +++ b/ga/19principal.tex @@ -281,11 +281,11 @@ \subsection{Principal fibre bundles} \ben[label=\alph*)] \item Let $M$ be a smooth manifold. Consider the space \bse -L_pM := \{(e_1,\ldots,e_{\dim M})\mid e_1,\ldots,e_{\dim M} \text{ is a basis of }T_pM\} \cong_{\mathrm{vec}} \GL(\dim M,\R). +L_pM := \{(e_1,\ldots,e_{\dim M})\mid e_1,\ldots,e_{\dim M} \text{ is a basis of }T_pM\} \cong_{\mathrm{LG}} \GL(\dim M,\R). \ese We know from linear algebra that the bases of a vector space are related to each other by invertible linear transformations. Hence, we have \bse -L_pM \cong_{\mathrm{vec}} \GL(\dim M,\R). +L_pM \cong_{\mathrm{LG}} \GL(\dim M,\R). \ese We define the frame bundle of $M$ as \bse From fc998e4ee7ad1eea1ea6734a1049541d2e54f44e Mon Sep 17 00:00:00 2001 From: kaesle Date: Mon, 30 Dec 2019 09:25:40 -0600 Subject: [PATCH 5/5] Typo fixed in definition of frame bundle T_pM -> L_pM --- ga/19principal.tex | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ga/19principal.tex b/ga/19principal.tex index 06dec0a..d2d40fd 100644 --- a/ga/19principal.tex +++ b/ga/19principal.tex @@ -294,7 +294,7 @@ \subsection{Principal fibre bundles} with the obvious projection map $\pi\cl LM \to M$ sending each basis $(e_1,\ldots,e_{\dim M})$ to the unique point $p\in M$ such that $(e_1,\ldots,e_{\dim M})$ is a basis of $T_pM$. By proceeding similarly to the case of the tangent bundle, we can equip $LM$ with a smooth structure inherited from that of $M$. We then find \bse -\dim LM = \dim M + \dim T_pM = \dim M + (\dim M)^2. +\dim LM = \dim M + \dim L_pM = \dim M + (\dim M)^2. \ese \item We would now like to make $LM \xrightarrow{\,\pi\,}M$ into a principal $\GL(\dim M,\R)$-bundle. We define a right $\GL(\dim M,\R)$-action on $LM$ by \bse