Quote from: HeRetiK on Today at 10:48:23 AM

Quote from: mjdamgaard on Today at 07:36:22 AM

If Ethereum mounted a successful 51% attack on Bitcoin, it would likely crash the value of Bitcoin, making Ethereum the new number one cryptocurrency.

Historically speaking, whenever Bitcoin crashed, it took the whole altcoin market down with it, including Ethereum. I highly doubt Ethereum would fare much better if it were the cause for such a crash (arguably, especially if it were the cause of the crash).

Quote from: mjdamgaard on Today at 07:36:22 AM

The cost of a 51% attack has been estimated to be $6–$20 billion [1]. This is only 1.3%–4.4% of Ethereum's current market cap. And it is only 0.5%–1.5% of its potential growth if Ethereum knocks down Bitcoin and conquers its full share of the cryptocurrency market.

The same paper estimates an attack on Ethereum to cost around $34 billion. That would be around 2.5% of Bitcoin's market cap so the "threat" kinda goes both ways.

These are two very good points.

First of all, it is true that the price of Ethereum seems to have roughly followed the price of Bitcoin in the past. However, (as User Stompix pointed out in the mentioned AltcoinsTalks thread) it is not at all impossible that Ethereum will be able to spin it as battle between 'PoS vs. PoW' (and 'Ethereum vs Bitcoin'), sort of like a 'Nokia vs Samsung' or 'Pepsi vs Coca-Cola' situation. Once the public hears that there is a contest between the two technologies, the price of the two might no longer remain correlated.

Your second point is also very valid. But first of all, if some of the Ethereum stakeholders start funding an attack, all they and other stakeholders would have to do is to in order to mitigate a reverse attack is to collectively stake a larger amount of the total Ether. And what's more, if one reads the Ethereum docs, see in particular https://ethereum.org/en/developers/docs/consensus-mechanisms/pos/#pos-and-security, it appears that the Ethereum stakeholders believe (and maybe rightfully so) that they will easily be able to revert a 51% attack, even if one happens.