Question: What did Stephen Hawking say about the Big Bang theory?
About the article "Gravitational wave", section "Astrophysics and gravitational waves".

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 and the Big Bang.
Stephen Hawking in particular has addressed a connection between time and the Big Bang.
In "A Brief History of Time" and elsewhere, Hawking says that even if time did not begin with the Big Bang and there were another time frame before the Big Bang, no information from events then would be accessible to us, and nothing that happened then would have any effect upon the present time-frame.
Upon occasion, Hawking has stated that time actually began with the Big Bang, and that questions about what happened "before" the Big Bang are "meaningless".
This less-nuanced, but commonly repeated formulation has received criticisms from philosophers such as Aristotelian philosopher Mortimer J. Adler.
Scientists have come to some agreement on descriptions of events that happened 10−35 seconds after the Big Bang, but generally agree that descriptions about what happened before one Planck time (5 × 10−44 seconds) after the Big Bang are likely to remain pure speculation. 
In theoretical physics, the Hartle–Hawking state, named after James Hartle and Stephen Hawking, is a proposal concerning the state of the universe prior to the Planck epoch.
Hartle–Hawking is essentially a no-boundary proposal that the universe is infinitely finite: that there was no time before the Big Bang because time did not exist before the formation of spacetime associated with the Big Bang and subsequent expansion of the universe in space and time.
Hartle and Hawking suggest that if we could travel backward in time toward the beginning of the universe, we would note that quite near what might have otherwise been the beginning, time gives way to space such that at first there is only space and no time.
Beginnings are entities that have to do with time; because time did not exist before the Big Bang, the concept of a beginning of the universe is meaningless.
According to the Hartle–Hawking proposal, the universe has no origin as we would understand it: the universe was a singularity in both space and time, pre-Big Bang.
Thus, the Hartle–Hawking state universe has no beginning, but it is not the steady state universe of Hoyle; it simply has no initial boundaries in time nor space.  
Hawking's marriage had been strained for many years.
Jane felt overwhelmed by the intrusion into their family life of the required nurses and assistants.
The impact of his celebrity was challenging for colleagues and family members, and in one interview Jane described her role as "simply to tell him that he's not God."
Hawking's agnostic views of religion also contrasted with her strong Christian faith, and resulted in tension.
In the late 1980s Hawking had grown close to one of his nurses, Elaine Mason, to the dismay of some colleagues, caregivers and family members who were disturbed by her strength of personality and protectiveness.
Hawking told Jane that he was leaving her for Elaine, and departed the family home in February 1990.
Following his divorce from Jane in the spring of 1995, Hawking married Elaine in September, declaring "It's wonderful—I have married the woman I love.
"Hawking pursued his work in physics: in 1993 he co-edited a book on Euclidean quantum gravity with Gary Gibbons, and published a collected edition of his own articles on black holes and the Big Bang.
In 1994 at Cambridge's Newton Institute, Hawking and Penrose delivered a series of six lectures, which were published in 1996 as "The Nature of Space and Time".
In 1997 he conceded a 1991 public scientific wager made with Kip Thorne and John Preskill of Caltech.
Hawking had bet that Penrose's proposal of a "cosmic censorship conjecture"—that there could be no "naked singularities" unclothed within a horizon—was correct.
After discovering his concession might have been premature, a new, more refined, wager was made.
This specified that such singularities would occur without extra conditions.
The same year, Thorne, Hawking and Preskill made another bet, this time concerning the black hole information paradox.
Thorne and Hawking argued that since general relativity made it impossible for black holes to radiate and lose information, the mass-energy and information carried by Hawking Radiation must be "new", and not from inside the black hole event horizon.
Since this contradicted the quantum mechanics of microcausality, quantum mechanics theory would need to be rewritten.
Preskill argued the opposite, that since quantum mechanics suggests that the information emitted by a black hole relates to information that fell in at an earlier time, the concept of black holes given by general relativity must be modified in some way.
Hawking also maintained his public profile, including bringing science to a wider audience.
In 1992 a film version of "A Brief History of Time"—directed by Errol Morris and produced by Steven Spielberg—was premiered.
Hawking had wanted the film to be scientific rather than biographical, but was persuaded otherwise.
The film, while a critical success, was however not widely released.
A popular-level collection of essays, interviews and talk titled "Black Holes and Baby Universes and Other Essays" was published in 1993 and six-part television series Stephen Hawking's Universe and companion book appeared in 1997.
As Hawking insisted, this time the focus was entirely on science.
He also made several appearances in popular media.
At the release party for the home video version of the "A Brief History of Time", Leonard Nimoy, who had played Spock on "Star Trek", learnt that Hawking was interested in appearing on the show.
Nimoy made the necessary contact and Hawking appeared as himself on "" in 1993.
The same year, his synthesiser voice was recorded for the Pink Floyd song "Keep Talking", and in 1999 for an appearance on The Simpsons.
In the 1990s, Hawking accepted more openly the mantle of role model for disabled people, including lecturing on the subject and participating in fundraising activities.
At the turn of the century, he and eleven other luminaries signed the ""Charter for the Third Millennium on Disability"" which called on governments to prevent disability and protect disabled rights.
In 1999 Hawking was awarded the Julius Edgar Lilienfeld Prize of the American Physical Society.
The same year, Jane Hawking published a memoir, "Music to Move the Stars", describing her marriage to Hawking and its breakdown.
Its revelations caused a sensation in the media, but as was his usual practice regarding his personal life, Hawking made no public comment except to say that he did not read biographies about himself. 
  "The Culture Show".
(Simpsons special)  "Alien Planet".
(Discovery Channel special)  "I Love the World".
(Discovery Channel commercial)  "Late Night with Conan O'Brien" (Episode 1752).
He was in a skit in which he made a phone call to guest Jim Carrey.
"Into the Universe with Stephen Hawking".
A three part miniseries about aliens, time travel and the past and present of mankind which is hosted by Hawking's voice  "Masters of Science Fiction".
A Science Fiction anthology series which is hosted by Hawking's (off screen) voice.
"Red Dwarf".
Hawking appeared in a special programme about the popular British science fiction series.
He praised its creators for their witty use of (pseudo) scientific theories and said he enjoyed watching the show.
"TV Offal".
Hawking appeared with host Victor Lewis-Smith in the pre-titles sequences of this show.
*At the beginning of the Season 6 cliffhanger, "", Data is seen playing poker with holographic depictions of Stephen Hawking, Sir Isaac Newton, and Albert Einstein.
Hawking portrayed his own hologram for this episode, making him the only guest in any "Star Trek" series to play himself.
When taking a tour of the set, he paused at the Warp core, smiled, and said, "I'm working on that."
During the tour, Hawking requested, and was allowed, to sit in the captain's chair of the Enterprise-D. *Brent Spiner ("Data") reportedly quipped, in an obviously tongue-in-cheek manner, that Hawking's cameo was "the most notable moment in television history since Albert Einstein guest-starred on "Gunsmoke"".
"The 11th Hour".
In this film about the effects of human activity on the environment Hawking gave explanations of these effects.
"Genius of Britain".
Hawking presented the links for a five-part 2010 Channel 4 series profiling British scientists.
"The Big Bang Theory".
(Episode 108: The Hawking Excitation)  
  "Computer Stew".
Hawking's image was animated and used as a character in several episodes.
"Doctor Who".
In the episode "Doomsday", Mickey Smith compares the Cybermen talking to the Daleks as "Stephen Hawking meets the speaking clock", due to both races' use of electronically produced or modified speech production.
"The Wrong Coast".
A segment of the show tells about a movie called Party Time Continuum, in which Hawking is portrayed as a time-travelling party-animal played by Seth Green.
"Weebl and Bob".
In their clip Balance, Stephen Hawking flies across the screen in his buggy and the various characters play around with his speech synthesiser against his will, making it say strange things, such as "I've wet my pants".
"User Friendly".
Stephen Hawking realizes in a power blackout that all the dark matter in the universe may be grues.
"Hawking".
A partly fictionalised 2004 biographical drama following Hawking's life as a Cambridge student, the initial onset of his motor neurone disease, and his meeting with his first wife.
"Legally Blonde".
Character "Arrogant" Aaron Mitchell, as an example of his own genius, mentions the possibility that "A Brief History of Time" may have been plagiarized from a paper he wrote as a child.
"Lost".
Eloise Hawking, a physicist (or pseudo-physicist) and mother of Daniel Faraday, has a small role in the show.
Her last name is clearly a reference to Stephen Hawking, just as Daniel Faraday references Michael Faraday and John Locke references the philosopher of the same name.
Superhero Movie.
Hawking, played by actor Robert Joy, first appears as a judge in a science fair who offers weed to the students and later helps Dragonfly (Drake Bell).
Knocked Up.
Jonah, while playing in a wheelchair, does an imitation of Hawking by saying (in a robot voice) "People think I'm smart because I speak in a robot voice."
The Vicar of Dibley.
In the episode 'Winter' from the Seasonal Specials, when casting for the Christmas Nativity play, Frank Pickle decided to base his version of the Wise Man on Stephen Hawking, speaking in a voice that sounded only slightly similar to Hawking's synthesized voice.
Father Ted.
In the episode 'Are you right there Father Ted' from the Third Season, Father Dougal mentions an occasion when Father Ted had done an impression of Stephen Hawking in a variety show only for Stephen Hawking to turn up unexpectedly.
Whose Line Is It Anyway?.
During a game of "Scenes From a Hat", one of the suggestion that got pulled out was "Celebrities who shouldn't release rap records".
Brad Sherwood made a reference to Stephen Hawking who "shouldn't put out a rap record".
Seinfeld.
In the season 4 episode The Handicap Spot, when Kramer and George are shopping for a wheelchair for a handicap woman, the store owner introduces them to the brand new, expensive "Cougar 9000" and that he put Stephen Hawking in one of them and "he's loving it!".
In the season 9 episode The Butter Shave, Jerry calls George "Stephen Hawking" when he sees George in a power chair, recently given to him by his boss, believing that George has injured both legs.
George's boss later finds out George's legs are okay when he sees George trying to flee from a group of old people chasing him on power chairs.
He is running on both legs, and carrying the power chair (after it lost power) as a way to escape the old people faster.
Malcolm in the Middle.
In one episode, the title character's friend, Stevie Kenarban, was so sad that his mother left his father, he talked by using a machine similar to that of Stephen Hawking.
The Big Bang Theory.
In the pilot episode Howard Wolowitz brings over a tape, stating that it is a Stephen Hawking lecture recorded in 1974, "before he became a creepy computer voice."
In an episode in Season 2, Leonard impersonates a fellow physicist's impersonation of Hawking on the phone.
In an episode in Season Four, it was mentioned that Sheldon had been tricked by his friends into going to the airport at 2AM to meet him.
In Season 6 episode 6, Sheldon Cooper and Stephen Hawking also engage in a game of 'Words with friends' over internet.
The two come up with pet names of Coop and Rolling Thunder.
In the end, to Sheldon's dismay, Hawking insults him.
The Double.
Oliver explains a null hypothesis.
The null hypothesis Oliver uses is 'Stephen Hawking is not Cassius.'
He then states, look through the pictures and show that Rolling Thunder is not Cassius.
The IT Crowd.
In episode 4 of season 3, "The speech", Roy and Moss present "The Internet" to Jen, under the form of a small black box, explaining that she can touch it as "it has been demagnetized by Stephen Hawking himself."
The Colbert Report.
Stephen Colbert, in character as a right-wing conservative pundit ala Bill O'Reilly, has frequently featured segments entitled "Stephen Hawking is Such an A-Hole", citing reasons such as the 'megalomaniacal' title of his program, "Stephen Hawking: Master of the Universe".
"There is only one master of the universe," Colbert responded, "and that's He-Man."
Goodnight Sweetheart.
Stephen Hawking is referred to by time-traveller Gary Sparrow twice: in an early episode Gary tells his friend Ron that "apparently Stephen Hawking thinks that time travel could be possible due to black holes" and continues "That's the easy bit.
Now tell me why time travel gives me wind.
"; and in a later episode "Mine's A Double" when trying to solve the problem of Gary being split into three personalities in clones of his body – when Ron questions his observations of the disruption of the space-time continuum, Gary remarks "Well unless anyone's got Stephen Hawking's phone number I suggest we give it a try".
.
In the 1994 series finale, "", in an alternate future, Data has assumed the Lucasian professorship at Cambridge, the post that Hawking held till September 2009.
Sliders.
In season 1 episode 7 "Eggheads", Quinn Mallory, in order to understand the rules of the MindGame (a game for which his alternate himself is a superstar in this Universe where mind prevails over physical abilities), read a book entitled "MINDGAME Rule Book - How to play How to win" written by Stephen Hawking.
The Avengers (2012 film).
When Captain America and Phil Coulson are on the Quinjet talking about Bruce Banner, Phil mentions Stephen Hawking, but Captain America does not know who that is.