Question: when did the big bang theory tv show start
[{'answer': 'September 24 , 2007', 'provenance': [{'wikipedia_id': '11269605', 'title': 'The Big Bang Theory', 'start_paragraph_id': 78, 'start_character': 56, 'end_paragraph_id': 78, 'end_character': 77, 'bleu_score': 1.0, 'section': 'Section::::Broadcast.\n'}]}]