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resources:books:baez_muniain [2017/12/27 12:29]
jakobadmin [Solutions to Exercises]
resources:books:baez_muniain [2018/05/05 17:17] (current)
jakobadmin ↷ Page moved from resources:baez_muniain to resources:books:baez_muniain
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 ====== Baez, Muniain: Gauge Fields, Knots and Gravity ====== ====== Baez, Muniain: Gauge Fields, Knots and Gravity ======
 + 
 <tabbox Why is it interesting?> ​ <tabbox Why is it interesting?> ​
 <WRAP imageshadow>​ <WRAP imageshadow>​
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   ​   ​
-<tabbox Reading Notes> ​+<tabbox Reading Notes/Summaries
  
-  * http://​michaelnielsen.org/​blog/​yang_mills.pdf+  * A great summary of Gauge, Fields, Knots and Gravity was [[http://​michaelnielsen.org/​blog/​yang_mills.pdf|published by Michael Nielsen]] ​
  
  
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 <tabbox Solutions to Exercises> ​ <tabbox Solutions to Exercises> ​
  
-  * [[https://​people.phys.ethz.ch/​~renes/​gfkg.html|Solutions by Joseph M. Renes]]. ("​Solutions to nearly all of the exercises in Part I, many of them in Part II, and none in Part III")  +
-  * https://​ncatlab.org/​brucebartlett/​published/​BaezMunian. (Solutions to all exercises in Part I and Part II.)+
  
 **Part I:** **Part I:**
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 **Part II:** **Part II:**
 +
 +--> Exercise 1#
 +**Q:**Given a Lie group $G$, define its identity component $G_0$ to be the connected component ​
 +containing the identity element. Show that the identity component of any Lie group is a subgroup, and a Lie
 +group in its own right.
 +
 +**A:** Suppose we have a path from the identity to $g\in G_0$. Now map this 
 +path to a new path by multiplying each element by $h\in G_0$. This path starts at $h$ and since the mapping is continuous, must remain in $G_0$. (Otherwise, smoothly mapping the group manifold to $\R^n$ would show a 
 +discontinuity at some point.) Thus $hg\in G_0$ for all $h,g\in G_0$.
 +
 +There'​s a certain tension between having a smooth manifold with disconnected pieces --- given a map from the 
 +the manifold to itself, one must take care that it does not have a discontinuous action, mapping some points in one component to another component. When this map is an element of the group, this requirement makes
 +$G_0$ into a subgroup.
 +<--
 +
 +//Source: [[https://​github.com/​joerenes/​Baez-Muniain-solutions|Solutions to Exercises in Gauge Fields, Knots and Gravity]] by Joseph M. Renes licensed under a Creative Commons Attribution 4.0 Licence.//
 +
 +
 +----
 +
 +See also:
 +
 +  * [[https://​people.phys.ethz.ch/​~renes/​gfkg.html|Solutions by Joseph M. Renes]]. ("​Solutions to nearly all of the exercises in Part I, many of them in Part II, and none in Part III"​) ​
 +  * https://​ncatlab.org/​brucebartlett/​published/​BaezMunian. (Solutions to all exercises in Part I and Part II.)
 <tabbox Discussions>​ <tabbox Discussions>​
    
resources/books/baez_muniain.1514374169.txt.gz · Last modified: 2017/12/27 11:29 (external edit)