[CC101-1] Why BTC can't be stopped: miners & costs

This is the first of a series of informative posts I will make about crypto, blockchain and applications (called CryptoCurrency101). You can check the pinned post on my profile for the compilation of all the posts.

I think yesterday I saw a post talking about how BTC miners were losing 3000 dollars per BTC mined and some people where worried that they could shit down their minning and BTC would die.

This cannot happen. Why? Because difficulty (the number of expected computations required to find the solution to a block) adjusts on the average time it takes to solve a block. For instance the equation would be:

Difficulty * = two_weeks/time_to_mine_previous-2016_blocks

The difficulty is implemented as a requirement of a leading number of zeros on the block header hash.

All in all even if 2/3 of the miners left due to costs being to high, difficulty would now be reduced to 1/3 after approximately 2 weeks (it's a smooth function so it never fully adjusts) but this reduced number of miners would lead to a reduced difficulty which would lead to reduced costs thus keeping the network alive. For instance if everyone stops minning difficulty would be so low someone could mine all the Bitcoins given in block rewards from a single computer.

The only problem with this is that you make it less secure which is something I will cover on another post.

If you want me to do an analisys of any topic let me know in the comments!