When all 21 million bitcoins are mined, several key changes will occur. Firstly, the block reward, the incentive for miners, will cease to exist. Miners validate transactions and add blocks to the blockchain in exchange for this reward. With no new bitcoins generated, miners will solely rely on transaction fees as an incentive. Transaction fees, payments attached to transactions, will become crucial for maintaining miner interest in securing the network.

The market dynamics are expected to shift. Bitcoin's fixed supply, analogous to precious metals like gold, could contribute to increased long-term value. As demand potentially continues to grow, the scarcity of bitcoins might drive up their price. The economic implications of a capped supply remain a subject of debate, with arguments about potential deflationary pressures and stability.

Security in the absence of block rewards is crucial. Miners, essential for transaction validation and network security, will increasingly depend on fees to cover operational costs. The fee-centric model aims to sustain the network's security over time. This transition could reshape the Bitcoin ecosystem, prompting changes in governance, incentive structures, and consensus mechanisms.

The fixed supply might lead to deflationary tendencies, challenging traditional economic models. However, proponents argue that it fosters stability and long-term value. The Bitcoin community is expected to continue evolving, addressing scalability, privacy, and functionality through technological upgrades. As the dynamics shift, the future of Bitcoin may witness changes in how it's governed, used, and valued. These projections are based on the current understanding of the Bitcoin protocol, assuming continued adoption, demand, and technological advancements. The actual future scenario will depend on various factors and the adaptability of the Bitcoin community to evolving circumstances.

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