Timeline of The Big Bang Theory

Timeline of events that happened on The Big Bang Theory.
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==Season 1==
This chronology is a timeline of events that occurred during the first season or approximately September 2007 to May 2008.1. “Pilot”August, 2007 to August, 2008  a box at UPS falls on Eric's head [The Locomotive Manipulation]
September 24, 2007 Penny moves in and meets Sheldon and Leonard, for whom it is love at first sight. Sheldon & Leonard fail to get Penny's TV from Kurt, her ex-boyfriend.
 2. “The Big Bran Hypothesis”
September 25, 2007 Penny asks Leonard to sign for some furniture she's having delivered
September 26, 2007 The furniture arrives.  Leonard and Sheldon get it upstairs with       difficulty, due to the non-functional elevator. Sheldon is so upset  by Penny's messy apartment that he returns later that night to tidy up  
September 27, 2007  Penny discovers the boys were in her apartment while she was      asleep and is furious, but she does later forgive them
September 28, 2007   Leonard, Sheldon, Raj and Howard try to assemble Penny's     furniture
3. “The Fuzzy Boots Corollary”
September 29, 2007  When Leonard sees Penny kissing Doug, he is devastated.
October 1, 2007 Leonard asks out Leslie Winkle, who says no
October 2, 2007  Leonard and Penny go on a  “date”  
4. “The Luminous Fish  Effect”
October 3, 2007 At a party to welcome Dr. Gablehouser, the new head of the Cal        Tech physics department, Sheldon is fired
October 4, 2007 Sheldon and Penny go to the grocery store
October 21, 2007  Sheldon's mom arrives
October 22, 2007 Sheldon apologizes to Dr. Gablehouser and is rehired (morning)
5. “The Hamburger Postulate”
October 22, 2007 Leslie Winkle approaches the group at the Cheesecake Factory  (nite)
Tuesday, October 23, 2007, Leonard & Leslie play in string quartet, then hook up
October 24, 2007 Leslie dumps Leonard
October 25, 2007 Sheldon & Leonard eat at the Cheesecake factory
6. “The Middle Earth Paradigm”  
October 26, 2007 after losing at paintball the boys are invited to Penny's  Halloween party
Saturday October 27, 2007  at Penny's Halloween party Kurt shows up. Penny kisses Leonard
7. “The Dumpling Paradox”  
Friday November 2, 2007 Penny's friend Christy arrives on Halo Night and launches into a sexual relationship with Howard   
Saturday November 3, 2007 – Christy moves in with Howard
November 6, 2007 Sheldon, Leonard & Raj eat at Szechwan Palace
Wednesday, November 7, 2007, on Halo night Christy leaves
8. “The Grasshopper Experiment”
November 8, 2007 Raj's parents tell him about Lalita Gupta
November 9, 2007 A date set up between Raj & Lalita. Raj learns he can talk to girls     if he is drunk
Saturday November 10,  2007 Raj & Lalita's date, she leaves with Sheldon
November 11, 2007 Sheldon sings at the Cheesecake Factory   
9. “The Cooper-Hofstadter Polarization”
March 17, 2008 Leonard learns he's been invited to speak about supersolids at Bose-   Einstein Condensates conference
March 18, 2008 Penny selects Leonard's wardrobe
March 18, 2008 Penny forwards to  Sheldon a LOL Cat e-mail [the Panty Piñata Polarization]
March 19, 2008 Leonard gives speech, but Sheldon shows up
March 20, 2008  Howard controls some lights in China
10. “The Loobenfeld Decay”
March 24, 2008  Sheldon and Leonard are invited to see Penny in “Rent”
March 25, 2008 Sheldon fabricates an elaborate lie why they can't go
Friday March 28, 2008 “Rent”  is performed
March 29, 2008  Sheldon worries the lie might not hold up
March 30, 2008 “Leo” shows up for his “intervention”
11. “The Pancake Batter Anomaly”     
March 31, 2008 Penny returns from a trip to Nebraska
Sunday April 6, 2008 Sheldon is sick   
April, 2008 Penny last has sex for six months [The Barbarian Sublimation]
12. “The Jerusalem Duality”
April 14, 2008 the boys meet Dennis Kim
April 15, 2008 Sheldon visits Howard and Raj to find a new job
April 16, 2008 at the reception Dennis shows up with a girl
April 17, 2008 the boys see Dennis in the park with the girl
13. “The Bat-Jar Conjecture”
April 21, 2008  the boys decide to enter the physics bowl
Saturday April 26, 2008 they discuss team names, but after a practice round Sheldon  is kicked off the team
April 28, 2008 Leonard, Raj and Howard draft Leslie Winkle for their team
April 29, 2008 The physics bowl, Sheldon loses
April 30, 2008 Leonard taunts Sheldon about his loss
14. “The Nerdvana Annihilation”
May 2, 2008 Leonard buys a time machine  
May 3, 2008 the time machine arrives. Penny is late for work and blames the boys playing with toys.  
May 4, 2008 Leonard wants to get rid of all his collectibles
May 7, 2008 Sheldon tells Leonard he has an eidetic memory [The Creepy Candy Coating Corollary]
15. “The Pork Chop Indeterminacy”
May 8, 2008 Missy Cooper arrives and all the boys try to hit on her, but none succeed
May 9, 2008 Missy leaves for Texas
16. “The Peanut Reaction”
May 12, 2008 the gang discuss birthdays
My 13, 2008 Penny blackmails Sheldon into having a birthday party for Leonard
May 17, 2008 Leonard's birthday party that he misses
17. “The Tangerine Factor”
May 19, 2008 Leonard asks Penny out on a date  
May 24, 2008 both Leonard and Penny talk to Sheldon then leave on their date
==Season 2==
This chronology is a timeline of events that happened during the Second Season or approximately May 2008 to May 2009
18. “The Bad Fish Paradigm”
May 24, 2008 Leonard & Penny return from their date
May 31, 2008   Penny confesses to Sheldon that she did not graduate, he  freaks out    about keeping a secret and moves out                          
June 1, 2008 Penny dumps Leonard
September, 2008 Penny's check engine light comes on [The Euclid Alternative]
19. “The Codpiece Topology”
September 21, 2008 - the boys attend the renaissance fair
September 25, 2008 – Leonard makes a date with Leslie Winkle
Friday, September 26, 2008  – Leonard's date with Leslie
September 27, 2008 – Leonard & Leslie's second date & break up
September 28, 2008 – the boys attend the renaissance fair
20. “The Barbarian Sublimation”
October 5, 2008 – Sheldon introduces Penny to Age of Conan
October 6, 2008  – Penny comes in Sheldon's room
Thursday, October 9, 2008  – Penny calls Sheldon @ work
October 10, 2008 – Sheldon tries to set-up Penny with a guy
October 11, 2008  – Tom shows up, Penny overcomes her addiction
21. “The Griffin Equivalency”
October 13, 2008 – Raj learns about People's 30 under 30 article
October 14, 2008  – Dr. Gablehouser fawns over Raj
Saturday, October 18, 2008 – Raj takes Penny to the People magazine reception
October 19, 2008 – Raj apologizes to Penny
22. “The Euclid Alternative”
October 20, 2008 – Penny drives Sheldon to work
October 21, 2008 – intervention and a visit to the DMV
October 22, 2008  – Sheldon on the driving simulator
October 23, 2008 – Sheldon lives at Cal Tech
23. “The Cooper-Nowitzki Theorem”
October 26, 2008 – Leonard & Sheldon lecture to undergrads
Monday, October 27, 2008 – Ramona shows up
Wednesday October 29, 2009 -  Ramona get Sheldon's food & gives pedicure
Saturday, November 1, 2008 – Sheldon does not leave to play paintball, but later tries to sneak off
                                            
November 2, 2008 - Sheldon caught by Ramona with a batman comic
November 3, 2008 everyone except Sheldon plays paintball
November 4, 2008 – Ramona finds Sheldon in shower with a gameboy, Sheldon seeks sanctuary with Penny
November 5, 2008  – Sheldon's breakthrough; Ramona leaves
November 6, 2008 – Sheldon meets  Kathy O’Brien, another grad student
24. “The Panty Piñata Polarization”
November 10, 2008 – Howard & Raj learn of the Top Model House
November 11, 2008 – Penny gets three strikes from Sheldon
Saturday, November 15, 2008, they eat at cheesecake factory – Penny ruins laundry night, but Leonard gives Penny Sheldon's Mom's telephone number. She makes Sheldon rescind strikes.
November 16, 2008 – Raj & Howard visit the Top Model House
25. “The Lizard-Spock Expansion”
November 17, 2008 - Howard needs help at the Mars rover lab, Leonard meets Stephanie
November 18, 2008  – Leonard & Stephanie on a date
November 19, 2008  – Leonard & Penny talk in the laundry room about Stephanie
November 20, 2008 – Leonard & Howard make up
November 21, 2008 – news of life discovered on Mars
26. “The White Asparagus Triangulation”
November 24, 2008 – Sheldon talks with Penny, then intrudes on Leonard and            Stephanie's date
November 25, 2008 -  Sheldon intrudes on Leonard and Stephanie's movie date
November 26, 2008 – Sheldon gives Penny zucchini bread, and Leonard hurt in           Sheldon's plan to make him appear macho
December 1, 2008 – Sheldon changes Leonard's Facebook status
27. “The Vartabedian Conundrum”
December 8, 2008 – Leonard & Sheldon discuss the roommate agreement cohabitation clause
December 9, 2008 – Penny shows Leonard Stephanie has moved in
December 10, 2008  – Leonard dumps Stephanie
28. “The Bath Item Gift Hypothesis”
December 16, 2008 – the boys meet David Underhill
December 16, 2008  – they do wii bowling  
December 17, 2008 – Penny meets  David
December 18, 2008 – Sheldon shops at Bath & Bodyworks, Leonard is  depressed until    Penny dumps David when she learns he is married
December 25, 2008 – Penny gives Sheldon a napkin signed by Leonard Nimoy  
29. “The Killer Robot Instability”
January 12, 2009 – MONTE complete, Penny insults Howard
January 13, 2009  – Howard is in a funk, they are challenged by Kripke
January 14, 2009 – Penny visits Howard, MONTE destroyed
30. “The Friendship Algorithm”
January 19, 2009 – Sheldon decides to become Kripke's friend
January 20, 2009 – Sheldon hands out a questionnaire to current friends
January 21, 2009 – Sheldon berates Leonard s answers, trip to bookstore
January 22, 2009 – Sheldon's flowchart  on how to make a friend
January 23, 2009 – Sheldon goes rock climbing with Kripke
January 24, 2009 – Sheldon tries rock climbing again  
31. “The Financial Permeability”
February 2, 2009 – Sheldon lends money to Penny  
February 3, 2009 – Leonard visits Kurt to collect money he owes Penny
February 4, 2009 – Penny repays Sheldon after Kurt repays her
32. “The Maternal Capacitance”
February 9, 2009 – Leonard learns his Mom will be visiting
February 10, 2009 – his Mom arrives
February 11, 2009 – his Mom visits Cal Tech, Leonard & Penny drink
February 12, 2009  – Leonard's Mom leaves
33. “The Cushion Saturation”
February 28, 2009 – Howard & Leslie hook up in the paintball shed
March 1, 2009 – Penny shoots the cushion in Sheldon's spot
March 2, 2009 – at supper Sheldon can't sit
March 3, 2009 – the cushion returns [error says schezuan palace closed 2 ya, but ate there 1ya ago ]
March 7, 2009 Leslie Winkle's sister gets married
March 8, 2009 – in paintball Sheldon  shoots Penny in revenge for shooting cushion  
34. “The Terminator Decoupling”
March 9, 2009 – the boys tell Penny about their San Francisco trip
March 10, 2009 -  Sheldon packs
March 11, 2009 – the train trip up the coast
March 12, 2009 – the conference
35. “The Work Song Nanocluster”
March 16, 2009 – Sheldon helps  Penny with her business
March 17, 2009 – she gets a 5000 ‘Penny blossoms’ order & they work al night to make  them
March 18, 2009 – she gets another order for 5000
36. “The Dead Hooker Juxtaposition”
March 30, 2009 – they discuss the tenant of 5A moving out
March 31, 2009 – the boys arrive to help Howard move out of Mom's house
April 1, 2009 – Alicia moves in to Apartment 5A
April 2, 2009 – Penny buys supper for the guys
April 3, 2009 – the catfight between Penny and Alicia
April 4, 2009 – fight aftermath with Penny's black eye
mid-April 2009 Raj's research into the composition of Trans-Neptunian objects reaches a dead-end  [the Pirate Solution]
37. “The Hofstadter Isotope”
Thursday, April 16, 2009  – Penny goes to comic book store to get a birthday gift for her nephew and meets Stuart
Friday, April 17, 2009 – Penny & Stuart go to art show  
38. “The Vegas Renormalization”
April 27, 2009 – Leslie dumps Howard  
April 28, 2009 – Leonard and Raj take Howard to Las Vegas where they buy him a  prostitute  
April 29, 2009 – they return to Pasadena
Raj had sex [per The Spaghetti  Catalyst]
39. “The Classified Materials Turbulence”
May 4, 2009 – Stuart asks Penny out on a date
May 5, 2009 – Stuart talks to Leonard, Stuart's date w/ Penny, Howard has problems  with the space toilet & they try to fix   
May 6, 2009 – everyone has a Thai meal  
40. “The Monopolar Expedition”
May 11, 2009 – Sheldon gets an e-mail from Dr. Siebert about National Science           Foundation expedition to the magnetic North pole
May 12, 2009 – Leonard, Raj and Howard decide to go with Sheldon
May 13, 2009 – Sheldon asks Penny if they can use the Cheesecake Factory freezer to practice
May 14, 2009 – the freezer test
May 15, 2009 – everyone talks to talk to Dr & Mrs Koothrapali  via webcam
May 16, 2009 Penny says to herself that she wishes Leonard wasn't going
May ___, 2009 – at MNP
===Notes===
While it is generally presumed that the first day of an episode is the date it is broadcast, there are exception, as at the start of this season.
==Season 3==
This chronology is a timeline of events that happened during the third season, approximately August 2009 to May 2010.
August 16, 2009 Sheldon sends notes to Beverly Hofstadter hre paper on quantum brain function  [The Maternal Congruence]
41. “The Electric can opener fluctuation”
August 16, 2009 – return after 3 months at magnetic north pole
August 17, 2009 – Sheldon runs away to Texas
August 18, 2009 – Leonard, Raj & Howard travel to Texas, talk Sheldon into returning
August 19, 2009 – Penny & Leonard finally hook up
42. "The Jiminy Conjecture"
August 20, 2009 – Everyone discusses Leonard and Penny's hookup last night, they catch a cricket
August 21 or 22, 2009 – they meet Dr. Crawley & Leonard & Penny decide not to just stay friends
August, 2009 – August 2010 Sheldon goes accidentally on booze cruise to Mexico [The Friendship Contraction]
September 22, 2009 – Leonard's mother and father divorce.
43. “The Gothowitz deviation”  
Monday October 5, 2009 -  Sheldon tries operant conditioning on Penny, while Howard & Raj go to a Goth club, but don't get tattoos
44. “The Pirate Solution”    
October 12, 2009 Raj is to be deported
October 14, 2009 - interview with Laughlin and Millstone, Sheldon asks Raj to help with “string theory implications of gamma rays from dark matter annihilation”  
October 15, 2009    Raj accepts the job with Sheldon
October 16, 2009 – Howard interrupts Leonard and Penny's night together, Sheldon & Raj disagree
Monday, October 18, 2009 -  Howard makes breakfast, Raj & Sheldon make up
45. “The Creepy Candy Coating Corollary”
October 19, 2009 – after playing “mystic Warlords of Ka’ah” Howard invokes the girlfriend pact with Leonard
October 20, 2009  – Howard reminds Leonard who asks Penny
Saturday, October 24, 2009 – mystic warlords of ka’ah tournament. Howard and   Bernadette's first date
October 28,2009 - suborbital test launch of the Jupiter-120 rocket
46. “The Cornhusker Vortex”
October 31, 2009 – after kite fighting Leonard invited to Penny's football party
November 2, 2009 – after Monday night football, Sheldon teaches Leonard about football
Saturday, November 7, 2009  – the football party
47. “The Guitarist Amplification”
November 9, 2009 – discussion of  Justin arriving
November 10, 2009 – Penny and Leonard keep arguing
November 11, 2009 – Sheldon at the Cheesecake Factory, big fight between Penny and Leonard
Sunday, November 15, 2009 – Justin arrives and sleeps on Leonard & Sheldon's couch
48. “The Adhesive Duck Deficiency”  
Monday, November 16, 2009  Raj, Howard & Leonard watch meteors, Penny dislocates  her shoulder, Sheldon gets a ticket   
49. “The Vengeance Formulation”
November 30, 2009 – Howard & Bernadette's third date
December 1, 2009 – Sheldon announces he will be on NPR ‘next week’
Thursday, December 10, 2009  – Sheldon asks Howard to review talking points
Friday, December 11, 2009, Sheldon is on Science Friday, Howard's bath where he        fantasizes about  Katie Sackhoff and later proposes to Bernadette
December 12, 2009 – Sheldon's revenge on Kripke
50. “The Gorilla Experiment”
December 14, 2009 – Bernadette express interest in Leonard's work
December 15, 2009 – Penny asks Sheldon to teach her “a little physics”, Howard      confronts Leonard
December 16, 2009 – Sheldon teaches Penny a little physics
December 17, 2009 – Howard & Bernadette square off in Leonard's lab 
December 18, 2009 – a meal with everyone
Sometime in 2009 - Bernadette's grandmother dies [The Maternal Congruence]
51. “The Maternal Congruence”
December 21, 2009 – Sheldon complains about Christmas shows
December 22, 2009 – Penny & Leonard decorate tree
December 23, 2009 – Leonard's mom arrives, goes out with Penny
December 24, 2009 – she leaves
52. “The Psychic Vortex”
January 11, 2010 – Howard & Bernadette double date with Leonard & Penny, who gets  upset when Leonard mocks her belief in psychics, Raj and Sheldon go out meet Abby & Martha
January 12, 2010 – Raj bribes Sheldon to go out again with the girls  
53. “The Bozeman Reaction”
January 18, 2010 – a break- in at Leonard and Sheldon's apartment
January 19, 2010 – Howard installs a security system  
January 20, 2010 – Sheldon leaves
January 21, 2010 – Sheldon in Bozeman
January 24, 2010 – Sheldon returns
54. “The Einstein Approximation”
February 2, 2010 – Sheldon stuck on a problem, Leonard, Penny, Howard and Bernadette  go disco roller skating,   Sheldon plays in ball pit
February 3, 2010 – Sheldon goes in Penny's apartment
February 4, 2010 – Sheldon visits the employment office 
February 6,2010 - Sheldon works at the Cheesecake  Factory
55. “The Large Hadron Collision”
February 8, 2010 – Leonard tells of trip to Geneva
February 9, 2010 – lunch at Cal Tech
February 10, 2010 – Sheldon plots to go on the trip by playing on Penny's sympathy
February 12,2010 - Leonard and Raj depart for Geneva
February 14, 2010 - Leonard & Raj in Geneva  
February 17,2010 - Leonard and Raj return from Geneva
56. “The Excelsior Acquisition”
March 1, 2010 – Sheldon learns he got a ticket & about Stan Lee comic book signing
Thursday, March 4, 2010 – comic book signing & Sheldon in court  
March 5, 2010 – Penny and Sheldon visit Stan Lee
57. “The Precious Fragmentation”
March 8, 2010 – they buy a box of stuff find a ring   
March 9, 2010 – they learn what the ring is, Sheldon tries to steal
March 10, 2010 – the contest to see who gets ring
March 11, 2010 – Leonard mails the ring to Peter Jackson, Sheldon tries to steal
58. “The Pants Alternative”
March 22, 2010 – Sheldon learns he won Chancellor's science award, but must give a speech
March 23, 2010 – intervention, Sheldon does yoga with Raj  
March 24, 2010 – Sheldon goes shopping with Penny and psychoanalysis with Leonard    
March 25, 2010- the banquet and speech
March 26, 2010 – Sheldon has questions about last night  
59. “The Wheaton Recurrence”
April 12, 2009 – Leonard tells Penny “I love you”  
April 13, 2009 – bowling w/Wil Wheaton  
April 14, 2009 – Penny dumps Leonard [8 months after “the Electric Can Opener        Fluctuation” as per “the Decoupling Fluctuation]
April 15, 2009 – guys at the comic book store in female super hero outfits  
60. “The Spaghetti Catalyst”
May 3, 2010 – Sheldon eats with both Penny & the guys
May 4, 2010 – Penny & Leonard talk in the laundry room    
Saturday, May 8, 2010 – Penny takes Sheldon to Disneyland  
61. “The Plimpton Stimulation”
May 10, 2010 – they learn of Elizabeth Plimpton's  arrival
May 11, 2010 – Elizabeth Plimpton arrives and hooks up with Leonard
May 12, 2010 – Penny confronts Leonard   
62. “The Staircase Implementation”
May 17, 2010 - Sheldon & Leonard fight
63. “The Lunar Excitation”
May 25, 2010 – they point a laser at the Moon with Zack and Penny there
May 26, 2010 – find Amy Farrah Fowler, Leonard talks to Leslie Winkle
May 29, 2010 – Sheldon & Amy meet for first time
April, 2010 to August, 2010 - Howard has his disastrous non-date with Emily Sweeney [The Relationship Diremption]
==Season 4==
This chronology is a timeline of events that happened during the Fourth Season, approximately July 2010 to June 2011.
July 2010 Jim Lee sketches Leonard at ComicCon The Good Guy Fluctuation
64. “The Robotic Manipulation”
September 23, 2010 – Howard introduces the robot hand
September 24, 2010 – Sheldon & Amy's date, Howard at the emergency room
65. “The Cruciferous Vegetable Amplification”
Thursday, September 30, 2010 – Sheldon discusses the singularity
October 1, 2010 – Sheldon & Penny go jogging
October 2, 2010 – Sheldon introduces the mobile presence device
October 3, 2010 – Sheldon sees Steve Wozniak  
October 4, 2010 – Penny sings soft kitty to the MPD
66. “The Zazzy Substitution”
October 5, 2010 – Amy meets Penny
October 6, 2010 – the guys meet at Penny's apartment  
October 7, 2010 – Sheldon & Amy break –up
October 9, 2010 – Sheldon & Penny talk in the laundry room
October 10, 2010 – Sheldon buys cats
October 11, 2010 – Sheldon's Mom arrives
October 12, 2010= Sheldon & Amy pay people to take cats
67. “The Hot Troll Deviation”
Tuesday October 12, 2010 – Howard sees Bernadette at the Cheesecake Factory
October 13, 2010 – Sheldon lets Raj buy desk, Howard talks to Penny about getting back together with Bernadette
October 14, 2010 – Raj moves in desk, Howard & Bernadette  meet
October 15, 2010 – Sheldon & Raj's war  
October 16, 2010 – Howard and Bernadette neck in the car
October 17, 2010 – Sheldon wears a gas mask
68. “The Desperation Emanation”
October 21, 2010 – Leonard is lonely, Sheldon asked to meet Amy's mom  
October 22, 2010 – Leonard invokes girlfriend pact with Howard
October 23, 2010 – Leonard's’ date with Joy
October 24, 2010 – Sheldon meets Amy's mom  
69. “The Irish Pub Formulation”
October 26, 2010 – Priya arrives
October 27, 2010 – lunch discussion about Priya
October 28, 2010 – insect sno-cones
70. “The Apology Insuffiency”
November 4, 2010 – Howard announces he's applying for a security clearance
November 5, 2010 – Agent Page visits Raj, Leonard & Sheldon  
November 6, 2010 – Howard doesn't get clearance
November 7, 2010 – Sheldon meets Agent Page & Neil de Grasse Tyson  
November 8, 2010 – Sheldon give Howard his spot
71. “The 21 Second Excitation”
November 11, 2010 – Penny watches Raiders of the Lost Ark
Friday Nov 12, 2010 – the guys go to see the film, the girls have a slumber party
Sheldon & Leonard go to the arcade [The Itchy Brain Stimulation]
72. “The Boyfriend Complexity”
November 18, 2010 – Wyatt arrives
November 19, 2010 – Wyatt leaves
At Thanksgiving, 2010 Penny and Zack go to Las Vegas and think they are fake married by an Elvis impersonator, however they really are married [The Thanksgiving Decoupling]
73. “The Alien Parasite Hypothesis”
December 9, 2010 – Amy sees Zack
December 10, 2010 – Zack and Amy meet
74. “The Justice League Recombination”
December 16, 2010 – they are invited to New Year's Eve party
December 31, 2010 Zack is Superman at the  comic book store party
75. “The Bus Pants Utilization”
January 6, 2011 – Leonard gets the idea for an equation app
January 7, 2011 – Sheldon is fired from the group
76. “The Love Car Displacement”
Tuesday, January 18, 2011 – Penny is  invited to Big Sur conference
January 21, 2011 – they leave for Big Sur
January 22, 2011  – the conference
77. “The Thespian Catalyst”
February 3, 2011 – Sheldon lectures
February 4, 2011 – Sheldon asks Penny for lessons in acting
Saturday, February 5, 2011  – his first lesson
February 6, 2011 – his second lesson
78.  “The Benefactor Factor”
February 10, 2011 – Dr. Siebert tells about a reception  for donors
Saturday, February 12, 2011 – the donors reception
Sunday, February 13, 2011 –Leonard & Mrs. Lambert  date
February 14, 2011 – second Leonard & Mrs Lambert date
February 15, 2011 - Leonard at Cal Tech
79. “The Cohabitation Formulation”
February 17, 2011 – Howard & Bernadette argue and Leonard visits Priya
February 20, 2011 – they eat at the Cheesecake factory  
February 21, 2011 – Howard briefly moves in with Bernadette
February 22, 2011 – Sheldon and Penny share a meal  
80. “The Toast Derivation”
Thursday, February 24, 2011 -  everyone eats at Raj's  
February 25, 2011 – Sheldon's new group of friends meet
81. “The Prestidigitation Approximation”
March 10, 2011 – Howard shows card trick                       
March 11, 2011 – Leonard tries to tell Penny to stay away  
March 12, 2011 – Penny interrupts Leonard & Priya's date at restaurant
March 13, 2011  – Sheldon tries card trick
March 14, 2011 – Sheldon tries card trick
82. “The Zarnecki Incursion”
March 31, 2011 – Sheldon's world of warcraft account hacked  
April 1, 2011 – they visit the hacker and Penny kicks him in the scrotum
April 2, 2011 – Penny & Priya climb the stairs in silence
83.. “The Herb Garden Germination”
April 7, 2011 – Sheldon and Amy attend a lecture by   Brian Greene  
April 8, 2011 – Sheldon and Leonard play wii archery
April 9, 2011 – rumor that Bernadette is going to dump Howard
April 10, 2011 – Howard says going to propose, Sheldon and Amy start rumor
April 11, 2011 – Howard proposes to Bernadette and she accepts
April, 2011 Penny gets a call back on hemorrhoid commercial [The Skank Reflex]
84. “The Agreement Dissection”       
April 28, 2011 - Sheldon's bathroom emergency & dancing night
April 29, 2011 Sheldon blackmails Priya and Leonard                                      
85. “The Wildebeest Implementation”
May 5, 2011 – Sheldon invents 3 handed chess and dinner of Leonard, Priya, Howard & Bernadette  
86. “The Engagement Reaction”
May 12, 2011 – Howard and Bernadette asked about wedding plans
May 13, 2011 – Howard's Mom and Bernadette have lunch, Mrs. Wolowitz in hospital
May 28, 2011 – 2 weeks later it is the end of Sheldon's quarantine
87. “The Roommate Transmogrification”
June 2, 2011 – Bernadette gets her Doctorate
June 3, 2011 – Raj moves in with Sheldon, Leonard learns Priya is moving back to India
June 4, 2011 – Raj & Penny emerge from Leonard's bedroom after a night of drinking.  
==Season 5==
This chronology is a timeline of events that happened during the Fifth season or approximately June 2011 to May 2012
2011 Amy starts shaving her legs The Vacation Solution
88. “The Skank Reflex Analysis”
June 4, 2011 – Leonard has an analysis session with his mom
Saturday, June 6, 2011 – the boys play paintball –penny gets commercial
day 3 – watch commercial  -much later
89. "The Infestation Hypothesis"
June 9, 2011 – Leonard's dinfast with Priya
June 10, 2011 – Sheldon tries to get rid of Penny's new chair
June 11, 2011 – Howard demonstrates cybersex devices, the chair thrown out
90. "The Pulled Groin Extrapolation"
June 16, 2011 – Amy stays & drafts Leonard to attend a wedding with her, Howard  and Bernadette fight about where they're going to live
Friday, June 17, 2011 – Leonard & Amy go to a wedding  
Saturday, June 18, 2011 – Bernadette serves Howard breakfast
91. "The Wiggly Finger Catalyst"
June 23, 2011 – Howard & Bernadette register at Macy's
June 24, 2011 – play D&D
June 25, 2011– Raj meets Emily
July 25, 2011 – learn Raj rich, Raj gives gifts to Emily  
July 26, 2011 -  Penny confront Emily
July 27, 2011 - Raj dumps Emily due to parents threat
July 28, 2011 – Raj seeks comfort from Penny  
92. "The Russian Rocket Reaction"
October 6, 2011 – Howard going to space, invited to Wil Wheaton's party
October 13, 2011 – discussion of Bernadette telling Howard's mom about space
October 14, 2011 – Wil Wheaton's party
93. "The Rhinitis Revelation"
October 20, 2011 – Mrs Cooper arrives
October 22, 2011 – Sheldon & mom do laundry
October 23, 2011 – tour Hollywood, Sheldon gets sick
94. "The Good Guy Fluctuation"
October 27, 2011 – Howard & Raj scare Sheldon
October 28, 2011 – Leonard meets Alice
October 29, 2011 – Leonard talks with Penny, ends it with  Alice & Priya
95. "The Isolation Permutation"     
November 3, 2011 – discussion of bridesmaid dresses
November 4, 2011 – Penny & Bernadette go shopping
November 5, 2011 – guys tell Penny & Bernadette that Amy upset
November 6, 2011 – Penny & Bernadette talk to Amy who gets drunk
November 7, 2011 – Bernadette asks Amy to be maid of honor
November 8, 2011 – Penny, Amy & Bernadette go shopping
96. "The Ornithophobia Diffusion"
November 10, 2011 – Leonard & Penny go to movies, Sheldon terrorized by bird
97. “The Flaming Spittoon Acquisition”
November 17, 2011 – Stuart meets Amy
November 18, 2011 – Stuart texts Amy
November 19, 2011 – Stuart & Amy date
November 20, 2011 – boys play mystic warlords
November 21, 2011 – Sheldon asks Penny out, then asks Amy to be girlfriend
November 22, 2011 – girls play twister
98. "The Speckerman Recurrence"
December 10, 2011 – Leonard gets e-mail from Jimmy Speckerman
December 11, 2011 – Leonard meets Jimmy Speckerman, girls visit charity bin
December 12, 2011 – Jimmy Speckerman chases Sheldon & Leonard, girls return to bin
Jan, 2012 Penny dings a Mercedes, but doesn't leave note [The Vacation Solution]
99. "The Shiny Trinket Maneuver"
Thursday, January 12, 2012 –  Sheldon & Amy on date & gets upset
January 13, 2012 – Penny and Sheldon go jewelry shopping
100. “The Recombination Hypothesis”
January 19, 2012 – Leonard asks Penny out
101. “The Beta Test Initiation”
January 19, 2012 – Leonard & Penny's date
January 20, 2012 – they watch Dr. Who
January 21, 2012 – Siri dinner & shooting range
102. "The Friendship Contraction"
February 2, 2012 – Leonard drives Sheldon to train store in Garden Grove  
February 3, 2012 – they end roommate agreement
February 4, 2012 – power outage
February 5, 2012 – Howard talks to Mass
103. "The Vacation Solution"
Friday February 10, 2012 -  Dr. Siebert tells Sheldon must take vacation
Monday, Feb. 13, 2012 -  Sheldon tries to sneak in to work
February 14, 2012 – Sheldon at Amy's lab
February 15, 2012 – Sheldon apologizes
February 16, 2012 –Howard & Bernadette discuss pre-nup
104. "The Rothman Disintegration”
February 16, 2012 – Prof Rothman's retirement party
February 17, 2012 – Amy gives picture
February 18, 2012 – Sheldon & Kripke argue
February 19, 2012 – Sheldon & Kripke play basketball
February 20, 2012 – Sheldon moves in office
105. "The Werewolf Transformation"
February 23, 2012 – Sheldon doesn't get haircut from Angelo  
Monday, February 24, 2012 -  Howard in Houston, Sheldon at hospital
February 25, 2012 – Howard returns from survival training
February 26, 2012 – Bernadette goes to Houston, mom already there, Penny cuts       Sheldon's hair
106. "The Weekend Vortex"
March 8, 2012 - games weekend proposed
March 9, 2012 – Sheldon shops at comic book store for present for Amy's aunt Flora  
Saturday, March 10, 2012 – 93rd b-day party Amy's aunt flora, Amy makes scene
107. "The Transporter Malfunction”     
March 29, 2012 – discuss Raj wants to get married
March 30, 2012 – meets Lakshmi
March 31, 2012 – date with Lakshmi, Sheldon breaks toy  `
April 1, 2012 – Raj ends with Lakshmi, Sheldon confesses
108. “The Hawking Excitation"
April 5, 2012 – Howard says Hawking coming to Cal Tech
April 6, 2012 – talk about Hawking
April 7, 2012 – Sheldon cleans Howard's belt buckles  
April 8, 2012 – Sheldon dresses as French maid
April 8, 2012 – Sheldon shops with Mrs. Wolowitz
April 10, 2012 - meets Hawking, faints
109. “The Stag Convergence”
April 26, 2012 – discuss bachelor party
April 27, 2012 – bachelor party
110. "The Launch Acceleration"
May 3, 2012 – mission cancelled
May 10, 2012 – guys shop, Amy & Sheldon's date. Leonard proposes
111. “The Countdown Reflection"
Friday – May 10, 2012 – Howard gives star necklace
Sunday May 12, 2012 – wedding of Howard & Bernadette
May 15, 2012 – Howard is launched into space
===Notes===
It is presumed that the first day of an episode is the date that episode was broadcast, but there are exceptions as in this season. 'The Wiggly Finger Catalyst' takes a month and would mess up the rest of the timeline.
==Season 6==
This chronology is a timeline of events that happen during the Sixth Season, or approximately between May 2012 and May 2013.
===112. “The Date Night Variable"===
*May 28, 2012 – Discuss Sheldon & Amy's date; Howard tells mom he is not moving.
*May 28, 2012 – 2nd anniversary of Amy & Sheldon's first date, Bernadette confronts Howard.
*May 30, 2012 – Bernadette & Howard talk.
===113. “The Decoupling Fluctuation”===
*July 6, 2012 – girls discuss boyfriends, they go to movies, Sheldon talks to Penny,:Howard & Bernadette talk.
*July 6, 2012 – they play cards, Penny can't break up with Leonard.
*July 7, 2012 – Penny talks with Amy & Bernadette.
*July 8, 2012 – Howard gets graffiti written on his face in space.
===114. “The Higgs Boson Observation”===
*August 9, 2012 – Howard & Bernadette talk.
*August 10, 2012 – Sheldon interviews Alex.
*August 11, 2012 – Amy gets suspicious of Alex, then Penny does.
===115. “The Re-Entry Minimization”===
*September 21, 2012 – Howard returns from orbit.
*September 22, 2012 – Howard returns to LA.
===116. “The Holographic Excitation"===
*October 25, 2012 – discuss Stuart's Halloween party.
*October 26, 2012 – Penny visits Leonard's lab,
*October 27, 2012 – Penny visits Leonard at lab.
*October 31, 2012 – Halloween party at the comic book store.
===117. “The Extract Obliteration"===
November 1, 2012 – Sheldon starts words with friends with Steven Hawking, Penny is back taking 1 course at college 
November 2, 2012 – Penny tells Leonard about her course  
November 5, 2012 – Howard has not played, Leonard rewrites 
November 6, 2012 – Penny mad at Leonard
November 8, 2012 – Penny got B- on paper by Amy & Bernadette, Hawking wins 
118. “The Habitation Configuration”
November 8, 2012 – during filming ‘Fun with Flags’  Amy asks Sheldon to tell Wil Wheaton to leave, when he don’t she does leave 
November 9, 2012 – Howard & Bernadette argue at the Cheesecake Factory re Howard moving out, Sheldon visits Amy
November 10, 2012 – Howard moves.  Sheldon visits Wil Wheaton
November 11, 2012 – Fun With Flags & Levar Burton
119. “The 43 Peculiarity”
November 15, 2012 – discuss Sheldon’s disappearance at 2:45  
November 16, 2012 – Raj & Howard follows Sheldon, enter room
November 17, 2012 – Howard & Raj discuss 43, Penny says she loves Leonard 
November 18, 2012 – spycam on Sheldon
November 19, 2012 – Sheldon plays hacky sack
120. “The Parking Spot Escalation’
November 29, 2012 – Howard gets assigned Sheldon’s parking spot 
November 30, 2012 – Sheldon steal Howard’s IronMan helmet, Howard sits on couch  naked
December 1, 2012 – after Bernadette has Amy’s car towed, Amy hits Penny
December 2, 2012  – Sheldon sits in parking spot, Sheldon & Howard agreement
December 3, 2012 – make-up dinner at Cheesecake Factory 
December 4, 2012 – Sheldon takes cushion to dry cleaners 
121. “The Fish Guts Displacement”
December 6, 2012 – Amy gets sick,  Howard and Bernadette’s eat with her parents  
December 7, 2012 – Penny teaches Howard how to fish
December 8, 2012 – Amy gets spanked, Howard & Mike go fishing 
122. “The Santa Simulation”
December 13, 2012 – discuss plying Dungeons & Dragons
Dec 15, 2012 - play Dungeons &Dragons, Raj w/girls at bar 
123. ‘The Egg Salad Equivalency”
January 3, 2013 – Alex asks Leonard to dinner
January 4, 2013 -  Sheldon’s council of ladies 
January 5, 2013 – Sheldon talks to Alex
January 6, 2013 – Sheldon at human resources  
January 7, 2013 – Leonard, Howard & Raj at human resources, tells Alex to take course
January 8, 2013 -  Penny‘s smart glasses
124. “The Bakersfield Expedition”
January 12, 2013 trip to Bakersfield con, girls read comics
125. “The Cooper-Kripke Inversion”
January 31, 2013 – Howard and Raj order action figures
February 1, 2013 – Sheldon & Kripke have to work together
February 2, 2013 -  Sheldon & Kripke trade work, Howard & Raj order 3D printer 
February 3, 2013 – Sheldon pretends to be sick and then to have sex with Amy,              Bernadette gets made at Howard about 3D printer
February 4, 2013 – Howard sells his half of 3D printer
126. “The Spoiler Alert Segmentation”
February 7, 2013 – Leonard moves out
February 9, 2013 -  Raj eats dinner with Mrs Wolowitz
February 10, 2013 – Raj still there,  big 4 way fight between Sheldon, Amy, Penny      and Leonard 
127. “The Tangible Affection Proof”
February 12, 2013 – Penny & Leonard have supper
February 13, 2013 – Raj & Stuart plan Valentine’s Day party 
February 14, 2013 – Alex buys gifts,  Penny sees Gretchen, Raj meets Lucy            
February 15, 2013 – Sheldon has an ice cream headache 
February 16, 2013 – Sheldon thinks he’s bitten by a Chinese bird spider
128. “The Monster Isolation”
February 14, 2013 – is day  3 of tangible affection proof 
February 21, 2013 – Sheldon’s Fun With Flags episode with Penny, Howard, Leonard and Bernadette visit Raj  
February 22, 2013 – Sheldon web chats with Amy, he thanks Penny, Lucy returns
Friday, February 23, 2013 – A Streetcar Named Desire performance, Lucy visits Raj
129. “The Contractual Obligation Implementation”
March 7, 2013 – the guys discuss promoting women in science 
Friday, March 8, 2013 – Sheldon, Leonard & Howard go to his school & girls skip &  Raj’s date 
130. “The Closet Reconfiguration”
Monday, March 31, 2013 – at party Sheldon finds letter from Howard’s father to Howard
March 16, 2013 – the girls force Sheldon to talk
March 17, 2013 – other party where  they reveal/don’t reveal message to Howard 
131. “The Tenure turbulence””
March 28, 2013 – they learn of Professor Tupperman’s death 
March 29, 2013 – everyone smoozes Ms. Davis & learns the tenure committee will be at  Professor Tupperman’s memorial service
Thursday, April 4, 2013 - memorial service for Professor Tupperman 
April 5, 2013 – Sheldon apologizes to Ms. Davis
April 13, 2013 –Sheldon finds a curly fry in his regular fries, makes an unscheduled video call to Amy [The Raiders Minimization]
===132. “The Closure Alternative”===
April 25, 2013 – discuss Sheldon’s disquiet at cancellation of Alphas, Raj finds Lucy’s Blog online.
*April 26, 2013 – Amy has a plan for Sheldon.
*April 27, 2013 – Leonard & Penny watch Buffy the Vampire Slayer.
*April 28, 2013 – Amy puts plan in effect, Bernadette & Penny talk about enthusiasm, Raj and Lucy's date.
===133. “The Proton Resurgence”===
*May 2, 2013 – Sheldon finds Professor Proton (Arthur Jeffries, Ph. D from Cornell) online.
*May 3, 2013 – Raj asks Howard to watch Cinnamon.
*May 4, 2013 -  Raj brings Cinnamon over to Howard's.
*May 5, 2013 – Cinnamon goes missing & Professor Proton comes over.
*May 6, 2013 – Sheldon fills in at a Korean family in Alhambra.
===134. “The Love Spell Potential”===
*May 9, 2013 – girls don't go to Vegas, and play dungeons & dragons with the guys.
===135. “The Bon Voyage Reaction”===
*May 16, 2013 – Howard tells Leonard he recommended him to Steven Hawking.
*May 17, 2013 – Leonard tells Penny.
*May 18, 2013 – party discussed.
*May 19, 2013 – Lucy meets Amy.
*May 20, 2013 – Sheldon & Penny shop for party.
*Friday, May 21, 2013 – party.
*May 22, 2013 – Leonard leaves.
==Season 7==
This chronology is a timeline of events that happened during the seventh season or approximately July 2013 to May 2014.
136. “The Hofstadter Insufficiency”
July 25, 2013 – Sheldon's nightmare about Leonard
July 26, 2013 – Raj & Howard at mixer, Amy & Bernadette at conference, Penny &   Sheldon hang out together
137. “The Deception Verification”
September 26, 2013 – Leonard returns
September 27, 2013 – Sheldon learns Leonard has returned
September 28, 2013 – Sheldon is an ass
September 29, 2013 – a meal
138. “The Scavenger Vortex”
October 3, 2013 - discuss hunt
October 4, 2013 – the hunt
139. “The Raiders Minimization”
October 10, 2013 – Sheldon & Amy watch Raiders of the Lost Ark     
October 11, 2013 – Sheldon reads Pride and Prejudice
 October 12, 2013 – Raj & Stuart photograph themselves
October 13, 2013 – Leonard & Penny have sex at work
October 14, 2013 – Raj & Stuart online, Sheldon & Amy watch Little House on the  Prairie, Penny's revenge  
140. “The Workplace Proximity”
October 17, 2013 – Sheldon & Amy on date night at the Cheesecake Factory    
October 18, 2013 – guys discuss working with girls, Howard  & Bernadette fight
October 19, 2013 – lunch at CAL tech;  Howard  & Bernadette fight again
October 20, 2013 – Leonard ‘talks’ to Howard & Sheldon
141. ”The Romance Resonance”
October 22, 2013 – they eat at the Cheesecake Factory
October 23, 2013 – Sheldon finds a new element  
October 24, 2013 – discuss song & element, Penny consults with Raj, Sheldon's error  
October 25, 2013 – Bernadette's in quarantine & Howard's sings a song to her
October 26, 2013 – Penny's dinner for Leonard, Amy's daydream
142 “The Proton Displacement”
October 30, 2013 – Amy, Sheldon & Leonard meet Proton in drugstore
October 31, 2013 – Leonard gets e-mail from Professor Proton
Friday, November 1, 2013 – girls jewelry night
November 2, 2013 – Sheldon visits Professor Proton at 7 am
November 3, 2013 – at Leonard and Professor Proton's experiment, Sheldon shows up  with Bill Nye  
Friday, November 8, 2013 – second jewelry night
November 9, 2013 – Amy visits Sheldon
143 – “The Itchy Brain Simulation”
November 14, 2013 – Leonard tells Sheldon about un-returned DVD, Penny confronts  Lucy
November 15, 2013 – Leonard tells Sheldon the owner of the video store is dead, Raj eats with Howard & Bernadette
November 16, 2013 – Raj has coffee with Lucy, Sheldon tells Leonard  he paid the late   fee on the DVD
Novemner 16, 2013 -  Raj has coffee with Lizzy
144 – “The Thanksgiving Decoupling”
November 27, 2013 – get invited to thanksgiving, Penny learns she's married
November 28, 2013 – (Thanksgiving)  Penny & Zack's marriage annulled
145 – “The Discovery Dissipation”
November 29, 2013 – Sheldon on “Science Friday”
November 30, 2013 – Sheldon plays w/trains, Wil shows up, Raj moves in with Howard & Bernadette, Leonard disproves
December 1, 2013 – Leonard posts his paper, Howard & Bernadette kick Raj out
December 5, 2013 –  Sheldon on “Science Friday”
146 – The Cooper Extraction
December 12, 2013 – learn about Missy's baby
December 13, 2013 – rest decorate the tree,  Missy's son born
December 14, 2013 – Sheldon returns & Stuart daydreams about Penny  
147 – “The Hesitation Ramification”
January 2, 2014 – Penny has good news
January 6, 2014 – they eat at the Cheesecake Factory
January 7, 2014 – Penny's scene cut from the 246th episode of NCIS
January 8, 2014 – Sheldon works on theory of humor; Penny proposes, Leonard declines
148 – “The Occupation Recalibration”
January 9, 2014 – Leonard & Penny reconcile, Penny quits working at Cheesecake Factory
January 10, 2014 – Sheldon starts enforced vacation,   Bernadette tries to replace destroyed comic book, Bert likes Amy and she ends up agreeing to  a date with him, but Raj and Howard get her out of it. Penny and   Sheldon travel around together.  
January 13, 2014 – Raj and Howard attend rock and mineral show with Bert
149 – “The Convention Conundrum”
January 30, 2014 – The guys fail to get Comic-con tickets online.
January 31, 2014 – Sheldon decides to set up his own convention.
February 1, 2014 – Sheldon calls Robert Downey, Jr. The girls go to tea. The boys decide not to buy scalped Comic-con tickets. Sheldon hangs out with James Earl Jones.
150. – “The Locomotive Manipulation”
February 6, 2014 – Amy tells Sheldon plan to travel with Bernadette and Howard to Napa  Valley on a train.
February 7, 2014 – the group discusses the trip, Leonard and Penny agree to watch Cinnamon
February 14, 2014 – Amy, Sheldon, Howard & Bernadette board the train, Cinnamon  eats chocolate & gets taken to vet, Yvette  Sheldon meets Eric and ignores Amy, but after a confrontation Sheldon kisses Amy.Yvette gives Raj her telephone number.
February 15, 2014 – Sheldon tells Leonard he kissed Amy
151 – “The Table for Polarization”
February 27, 2014 – it is suggested that Sheldon & Leonard get a dining room table
February 28, 2014 – Leonard & Penny go to buy a table, Howard gets call about returning to outer space
March 1, 2014 – the table is installed in the apartment, Sheldon tries to break up with      Amy, Howard's intervention
March 3, 2014 – Howard goes to the doctor
March 4, 2014 – the eat at the apartment  on the table
152. ‘The Friendship Turbulence”
March 5, 2014 – Raj watches “West Side Story”
March 6, 2014 – they discuss Penny's acting career
March 7, 2014 – Howard invites Sheldon to Houston, Raj gets Amy to contact Emily, Penny's car dies
March 8, 2014 – they play risk, Emily turns down Raj,
March 9, 2014 - Howard & Sheldon leave for Houston, Leonard gives Penny a car, Rmily and Amy's coffee date
153. “The Mommy Observation”
March 13, 2014 -they play Raj's murder mystery game, while Sheldon and Howard pay an  unexpected visit to his mother
154. “The Indecision Amalgamation”
April 2, 2014 -   Sheldon can't decide between X-box and PS 3, Penny gets an offer to star in   “Serial Apeist 2; Monkey See, Monkey Kill”, Raj meets Emily again
April 3, 2014   -  Sheldon ruins date night with Amy, Penny decides to take part,  Raj gets  text from Lucy
April 4, 2014 - Penny and Leonard meet Wil Wheaton
April 6, 2014 - Amy and Leonard go to the store, Raj's date with Emily
April 7, 2014  - Penny and Wil Wheaton start filming Serial Apeist 2: Monkey  See, Monkey Kill.                 
155. “The Relationship Diremption”
April 10, 2014 – Sheldon questions his work on string theory.
April 11, 2014 – Raj arranges a double date for him and Emily with Howard and Bernadette
April 12, 2014 -   Sheldon gets a haircut from Penny, then drinks too much & Emily and Howard and Bernadette's double date
April 13, 2014 -    Sheldon wakes up to find he was reading about Geology and called     Hawking. He and Howard talk.
156. “The Proton Transmogrification”
May 1, 2014 -  Arthur Jeffries dies
May 2, 2014 – Sheldon watches Professor Proton on YouTube
May 4, 2014 – Leonard and Penny go to Arthur Jeffries funeral, Sheldon dreams of      Professor Proton, Amy and Bernadette bake a Death Star cake
157. “The Gorilla Dissolution”
May 8, 2014 – Mrs. Wolowitz injured in treadmill accident
May 9, 2014 – Howard & Bernadette discuss Mrs. Wolowitz's care
May 10, 2014 – Raj and Sheldon go to see The Amazing Spiderman 2 and meet Emily. Penny and Will Wheaton get fired from Serial Apeist 2: Monkey See, 'Monkey Kill, Penny and Leonard get engaged
May 12, 2014 – Howard and Bernadette relax while the nurse works
158. “The Status Quo Combustion”
May 15, 2014 – Penny and Leonard announce they are engaged
May 16, 2014 -  Sheldon meets with President Siebert about changing field of study, Another nurse quits, Leonard tells his Mom about his engagement, .Penny tells her family, and very briefly works as Mrs. Wolowitz's nurse. The Comic Book store catches on fire.
May 17, 2014 – Sheldon writes e-mail to faculty senate. Sheldon and Leonard discuss  new living arrangements. Sheldon vents to Amy, then goes to the train station
May 18, 2014 – Stuart is working as Mrs. Wolowitz's caregiver.
==See also==
Timeline of Young Sheldon
Category:Events
Category:Timeline