f M E A P H V S E P J J T N P P D S F A J f S C P J Y N f A E N P R H A r r r o o u e v c t t e i e a e h a l o n r d r h n a v v a i i o o e o e a e a e a a a a n o e m c a n i i i t t t t c b i r w g t i o r l m m n m I p n s c t e e r e t d l n n o - h t n n m a o u o W i e i l e m h i t i a A r h r r i c H i a a l i t c a r S l e l r s l l m a p B W a h J J J M u i o T d e r l s i t i o i S G G t n . a l l A u n a u u u c g a y i d a l o a n t s a D i A s r M M Z e B t a J r e h i o o a l l l d e r M s n u S H n r y y y C k . W . l C d l l i L o S a e m e n A a r a d W V d l v L L a G o r a a I p d l m 1 1 1 C r h B g . i s c a a l o o i s r d o n e a b f r s c e , , , e a t l k a A r a P a o o e r k e c n e a e t g b n o i i h i e v i n r 2 2 2 a i i e n l b n i i s h e d - r v f r n a n i n n e d i r k c s 0 0 0 H f e c m S n e i n l r n l S e e o g l i A h , e o e e 0 0 1 e l i t i r t c r a a d e a t a o h r r D t r 9 9 0 i r s o m i s g d s B o s i t k a e r t n e y y e n d n T c u t o m r h S e Th e Insti tute Letter I n R D P M P V P M D N B J C J C R V S M F C C M P M I R C A O G F P G F s r a e p e e e e i l r i a o i o l a o h u h h h a l i l a a v e o c a a a o i c b m f e e l e t t t r i t c g b c a n a a i f v v r a r t e t r r e e e e h r r r r r e t e g n n r u o h t e i e i i r r o r a i t i t i i c t e s r r r r Spring 2 009 s a e i r m d d r r o a i i o g d l r e r r l a s y n i s G t t W n n e r y m m t C L G R P J i t n n i e y W A K a d a D L C O D s a . D S o r t a G . P . o . P l A L o a a n a L . n W . L a . f a r . r E B . S e B K n G B . d W . r . n n b H a e P v a M u l a L i l B H T F J e . s W m . H a d o C L h l a m . i a g t i n t . a a t o E a g g e B e r n B n w a i l a s i e L r a a h h g l D r e n u i o l n t r o n z o i m r j n c l z i s b l b e s i o i e s e l g o r a o t b d i r s g n e y M e o f c l i n i o r n e u r i c t e s o e l c s t y r n h a s e k r a l g k i s i s n e o h w i IAS j o n i e l m n l c e o i n t l s t u c a s i a u h r n d o t a k n n n s z e s , h n d i Lett J n d r t . e r Figure 3 R H I H L M M T T B A M S P R S I W J D E N E A P M D w J m n a a h i e r o a a r n d h r i a a e a a r w d i a a a s i m m n i i i t e l n d c v S u d m n m l e l v v n a t c n e r r r p s e f w l h i a i a i i o r s t i t c r e e c n r b e t h t s d d n a n i i i E e n i t l e . u e y d p e s s n n s l y y i e d e S n e a w a F l c . i a E h o t t F M e d H J B o n v o e . u u W D e E R r s S L r s L . v . e . n M W J . d . e e s c G e H M . D . f . e S H . n E h N . i P , o l R S h e S V D v d c L a u K S . n r r n W i a e a m r N i . K u m s e o h t u u x i t m a S t . r a n r i r e v W u h b g e o n i l i b w i e c e q e C p i g s l s e r l o d w a e h d l h l l t r e u m o o l h e r H a l e s n l n y a t i n s m o n a l i t m u J s n s o a L l t i s r 2 Figure 4 e m d L t i n f d s a e t Figure 1 E f r z n m t n i a N 0 s n e N n a y O 0 n C ’ 0 n O 8 9 L 5 A 4 N 0 O D D N A P H S o E P D e r l u E i a e n n M b e v a s A d l e m s t H i - e c e I c y a i N h o A n n i A l a u K f o D f a R n t a m A v i g r i f a A r i y e o v s t M s I v h e u , Figure 2 N e Figure 5 t , e I s o n d r P o : @ ? s r f t i i i n y a t u c o s e t u . Feynman Diagrams and Beyond e e t r o d f c n u o Physicists have used Feynman diagrams as a tool for calculating scattering amplitudes that describe particle h , r a N A n interactions for more than six decades (see article, page 4). Their broad utility was due initially in large part J d g v 0 e a 8 to the seminal work of Freeman Dyson, Professor Emeritus in the School of Natural Sciences.