We don't know the current peak capability of quantum computing as it is still in its early stages but one thing is sure that it will be a problem for bitcoin because as what is on the paper says about quantum computing, it will be far faster than any computer in the market and in any laboratories. We also have to stop telling people that quantum computing will be able to hack the private key of everyone, yes it has faster calculations but that doesn't mean that it will crack the key in a matter of days, if right now the current brute force duration is the heat death of the universe, maybe with quantum computing, the time it takes will be cut in half but that is still a whole lot of millennia.
Cryptography and quantum computers
A lot of digital ink has been spilled on how quantum computers pose an existential challenge to asymmetric cryptography as it is commonly used. As a result, we will not go into great detail about this, instead focusing on the aspects that are important to the analysis in this article.
A private-public key pair is developed in asymmetric cryptography in such a way that the two keys have a mathematical relationship. The private key is kept private, while the public key is made publicly accessible, as the name implies. Individuals can use their private key to create a digital signature that can be validated by someone with the corresponding public key.This system is widely used in the financial industry to prove transaction validity and honesty.
Asymmetric cryptography's security is founded on a mathematical concept known as a "one-way trick."The public key can be easily obtained from the private key, but not the other way around, according to this theory. All known (classical) algorithms for obtaining the private key from the public key take an astronomical amount of time to complete and are therefore impractical.However, in 1994, the mathematician Peter Shor published a quantum algorithm that can break the security assumption of the most common algorithms of asymmetric cryptography. This means that anyone with a sufficiently large quantum computer could use this algorithm to derive a private key from its corresponding public key, and thus, falsify any digital signature.