Are there any Hadiths indicating that Ali (may Allah be pleased with him) was the most knowledgeable person on earth after the Messenger of Allah (peace be upon him)? And is the Hadith "I am the city of knowledge and Ali is its gate" authentic? And does this Hadith prove his superiority in knowledge over Abu Bakr and Umar (may Allah be pleased with them)?

None of the respected scholars has ever said that Ali was more knowledgeable or more jurisprudent than Abu Bakr and Umar. Rather, scholars have unanimously agreed that Abu Bakr was more knowledgeable than Ali. The Prophet, peace and blessings be upon him, used to approve of Abu Bakr's rulings and judgments, and he would consult him and Umar first. He said about them: "If you both agree on a matter, I will not oppose you," and "Follow those who come after me: Abu Bakr and Umar," and "If the people obey Abu Bakr and Umar, they will be guided." Ibn Abbas used to issue fatwas based on the opinions of Abu Bakr and Umar, prioritizing them. Furthermore, Abu Bakr and Umar had a closer relationship with the Prophet than others, especially Abu Bakr, who often stayed up late with him. The Prophet, peace and blessings be upon him, appointed Abu Bakr to lead the prayers and rituals, and he made him a commander over Ali during the Hajj. It has been established that Abu Bakr was the most knowledgeable of the Companions and the most capable of resolving disputes. As for the hadith, "I am the city of knowledge and Ali is its gate," it is very weak and fabricated.