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Description

The first lecture in a series of 14 lectures, given by Davide Gaiotto of the Perimeter Institute at the 2013-2014 PSI. This lecture provides an introduction to perturbative string theory.
If you're having trouble seeing the board at any point in the lectures, you can check out this pdf with snapshots of the board -- one shot for each change that occurs:
http://pirsa.org/pdf/loadpdf.php?pirsa_number=14010070
NOT my videos! All rights, credit, etc. go to the Perimeter Institute, which can be found at the website linked to below) would be a nice addition. All the videos come from, and can be downloaded from in various formats and from previous years, the Perimeter Institute (where these lectures took place) website:
http://perimeterscholars.org/451.html
Before attacking these topics, it would be wise have first have familiarity with quantum field theory. Excellent lectures on these topics given by David Tong (of Cambridge) and Francois David at the Perimeter Institute in 2009 and 2011, respectively, can be seen here:
https://www.youtube.com/playlist?list=PLCFDAC024C6B67171&feaÂture=plcp
https://www.youtube.com/playlist?list=PLNhSjK9aGXjoc6EhKcaLMYpafw0ROmR1w&feature=mh_lolz
In addition to that, you can check out the wonderful lectures on string theory and M-theory by Leonard Susskind at Stanford:
https://www.youtube.com/playlist?list=PLA2FDCCBC7956448F
https://www.youtube.com/playlist?list=PL3E633552E58EB230
You can also find lectures from the 2011-2012 PSI review course, given by Freddy Cachazo:
https://www.youtube.com/playlist?list=PLNhSjK9aGXjpHsokpYc6dTOjYGp_b3wCe
Moreover, there are TONS of books on the subject. I personally suggest the following two for introductions:
http://iate.oac.uncor.edu/~manuel/libros/Modern%20Physics/String%20Theory/A%20First%20Course%20in%20String%20Theory%20-%20B.Zwiebach.pdf
http://www.galaktiskeparti.no/PDF%20files/String%20Theory%20and%20M-Theory%20A%20Modern%20Introduction~tqw~_darksiderg.pdf
The classic textbooks are:
http://stringworld.ru/files/Polchinski_J._String_theory._Vol._1._An_introduction_to_the_bosonic_string.pdf
http://stringworld.ru/files/Polchinski_J._String_theory._Vol._2._Superstring_theory_and_beyond.pdf
http://www.amazon.com/Superstring-Theory-Introduction-Monographs-Mathematical/dp/0521357527
http://www.amazon.com/Superstring-Theory-Amplitudes-Phenomenology-Mathematical/dp/0521357535/ref=pd_sim_b_1?ie=UTF8&refRID=149KJJMQ51ZHJNX13YMG
There's also David Tong's notes:
http://arxiv.org/pdf/0908.0333.pdf
And, lastly, if you are interested in the mathematical perspective on string theory then you can check out the following books:
http://www.amazon.com/Mathematical-Aspects-String-Advanced-Physics/dp/9971502739
http://www.amazon.com/Mirror-Symmetry-Clay-Mathematics-Monographs/dp/0821829556/ref=pd_sim_b_1?ie=UTF8&refRID=0KRC8KTNWJNWCZ5EH5X5
http://www.amazon.com/Dirichlet-Branes-Symmetry-Mathematics-Monographs/dp/0821838482/ref=sr_1_1?s=books&ie=UTF8&qid=1413352613&sr=1-1&keywords=D-branes+aspinwall
http://www.amazon.com/Tropical-Geometry-Symmetry-Conference-Mathematics/dp/0821852329/ref=pd_sim_b_3?ie=UTF8&refRID=0KRC8KTNWJNWCZ5EH5X5

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