How Does a “Chain Split” Occur and How Is It Resolved by the Longest Chain Rule?

A chain split, or temporary fork, occurs when two or more miners find a valid block almost simultaneously, leading to two different chain tips. This is a natural part of decentralized mining.

The longest chain rule resolves this by having all nodes temporarily hold both chains until one of them finds the next block. Once a subsequent block is found, the chain it extends becomes the longer one, and the shorter chain's block is orphaned, with the network quickly converging back to a single, longest chain.

Can a Re-Org Be Non-Malicious (E.g. Due to Network Latency)?
What Is the Difference between the “Longest Chain Rule” and the “Heaviest Chain Rule” in PoW?
What Is a “Stale Block” and How Does It Relate to the Longest Chain Rule?
What Happens to the Block Rewards of the Blocks That Are Orphaned by the Longest Chain Rule?
What Is the Concept of the ‘Longest Chain Rule’?
What Is a “Preimage Attack” and How Does It Differ from a Collision Attack?
What Is the “Longest Chain Rule” and How Does It Prevent Confirmed Double-Spending?
If the Hash Rate Suddenly Doubles, How Soon Will the Next Difficulty Adjustment Occur?

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