Question: how can a proton turn into a neutron
[{'answer': 'positron emission', 'provenance': [{'wikipedia_id': '4651', 'title': 'Beta decay', 'start_paragraph_id': 1, 'start_character': 382, 'end_paragraph_id': 1, 'end_character': 399, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '4651', 'title': 'Beta decay', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1034, 'bleu_score': 0.885709249199872, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2070786795376829614}, 'section': 'Section::::Abstract.'}]}]