Bitcoin Forum

Is there still a significant number of miners with the equipment required to process proof of work for bitcoin?  Is there a danger in that the cost to run such equipment being so high that it leaves very few miners able to afford to do the proof of work, and thus it leaves only one or two miners and introduces the possibility through collusion to start manipulating the blockchain?

The number of miners is actually still increasing, so you should not be worried.
Also if miners would leave, after a number of blocks the difficulty would adjust, so the mining will become more profitable for the remaining ones.

The number of miners of Bitcoin is still increasing?  Isn't the equipment required and power consumption to high for most people to even consider?  Maybe I just don't understand the mechanics of the proof of work system well enough, but it seems to me that only the superrich can afford to run a Bitcoin mining operation and we all know how greed can take over even the most altruistic of people.

 The strongest property of Proof of Work is that you not only need to spend resources to establish mining, but also to sustain it, so even if majority of miners decide to conspire, they will have to keep burning electricity to continue their attack, which can't be profitable for long (if it was profitable in the first place, which is a big question).

Next, you have some misunderstanding that miners control blockchain - they don't, every full node validates it independently, so miners can't simply break the rules, they can only erase recent blocks.

May be I am a little off topic here-
The total number of full node on 4th November 2019 was 9379 (https://bitcointalk.org/index.php?topic=5116075.msg49988183#msg49988183), which as of now has been increased to 11002; can't we take it as miners are increasing too? Well, you are correct that at some point we may see only a couple of pools will have most of the power which may later intend to collude the system if necessary. I don't know how much it's possible though.

https://i.imgur.com/8OVGfF0.png

It is wrong to believe that any single individual can act as a dominant force. If someone takes the mining difficulty to the level that it becomes too difficult for others to mine due to the high cost of equipment then either of the following two things will happen:

• That someone would be a pool where thousands of miners collaborate as single force so even though one unit of processing power is mining block but the mining reward will still be distributed among number of miners.
• The price of bitcoin will rise too high that buying additional equipment for mining will become relatively cheaper to block reward. So new competition to above pool will enter in the scope.

I know that In order to mine bitcoin an ASIC processor setup is required, I didn't take into account that mining pools are involved. Independent consensus is the key here as you guys have pointed out.  Thank you all for clearing that up for me.