Ethereum's Difficulty Bomb: A Series of Delays and Upgrades

The Ethereum network has been navigating through a series of delays and upgrades to its built-in protocol feature, known as the difficulty bomb. This mechanism increases mining difficulty over time to force the network into proof of stake, reducing energy use by up to 99.95%.

However, the difficulty bomb's initial implementation created a problem: it made mining less profitable and slowed down block times. To address this issue, developers implemented various upgrades and delays using EIPs (Ethereum Improvement Proposals).

The first delay was introduced by Byzantium in October 2017, which delayed the difficulty bomb for approximately 1.5 years. Later updates, such as Muir Glacier, London, Arrow Glacier, Gray Glacier, and Paris, continued to push back the deadline, each time buying more time for a safe transition to proof of stake.

The Merge in September 2022 marked a significant milestone, transitioning Ethereum from proof of work to proof of stake. This upgrade effectively defused the bomb by using the total terminal difficulty as the basis for transition, avoiding the risk of forking a malicious chain built by a minority of hash-power.