Ever since Bitcoin came into existence, fresh varieties of FUD (fear, uncertainty, and doubt) have consistently been deployed to forecast its collapse. Even so, Bitcoin has expanded into a multi-trillion dollar asset and started securing its position within the global monetary architecture. Lately, the specter of a cryptographically relevant quantum computer (CRQC) allowing an adversary to derive private keys from public keys and authorize Bitcoin transactions to transfer funds belonging to others has resurfaced as an updated variant of FUD. Does this constitute a plausible danger to Bitcoin’s ongoing expansion? Simply put, no. There is zero proof that a CRQC will materialize within a decade, and it remains uncertain whether such a system will ever be constructed. The quantum threat continues to be purely FUD.
State of the Art
Up to this point, no quantum computing apparatus has ever calculated anything beyond the capabilities of an advanced 6-year-old (verified empirically). Quantum computers represent extraordinary technology and highlight the genuinely science-fiction-grade achievements of the contemporary era. These machines leverage foundational innovations including optical tweezers, laser cooling, superconducting flux qubits, electromagnetic traps, dilution refrigerators, and numerous others. Inside these devices, individual qubits are forced into specific subatomic configurations (varying across candidate technologies), entangled into superpositions, manipulated to simulate computations, and subsequently evaluated and interpreted via their subatomic characteristics. The astonishing reality is that these systems exist and can be adjusted to execute meaningful calculations across a limited number of inputs. The sobering reality check is that (taking an illustrative candidate technology as an example) performing a calculation achievable by a small child demands enough energy to cool a Texas high school, many hours of preparation, and additional hours of post-processing.
Reading the Future
I understand what is crossing your mind, “yet vast amounts of capital are pouring into quantum computing.” Does financial investment flowing into a sector correlate with the pace of practical technological advancement in that domain? Not really. In truth, one could argue that until the correct underlying hardware is engineered and product-market alignment is validated, capital injected into a sector maintains a negative correlation with the probability of applicable technology emerging. This becomes evident when contrasting NASA’s Space Shuttle initiative with SpaceX’s Falcon 9. SpaceX utilized predominantly established science and translated it into execution to address a clear market requirement for dependable and cheaper orbital access, achieving a program expenditure of under $5 billion prior to its inaugural crewed flight. The Space Shuttle demanded approximately $50 billion to arrive at its first crewed mission. Not only did the Falcon 9 require an order of magnitude less capital to create, but it also maintains a flawless crew safety track record to this day. Various factors account for these distinctions, yet the situation demonstrates that limitless funding cannot force an unprepared technology into practicality. Applying this to quantum computing: we observe that with massive financial backing directed at the issue, high-cost technology demonstrations become achievable. However, this conveys nothing regarding whether additional capital will deliver the ultimate goal of stable, low-error qubits (comparable to the reliability of the Falcon 9). No amount of sustained investment in the Space Shuttle initiative would ever have yielded the affordability and high dependability of the Falcon 9, and it remains highly likely that continued development at any cost will never render any current quantum computing approach reliable enough to crack a single key pair.
Presently, you might be pondering, “what about all the recent breakthroughs?” Two crucial factors must be kept in mind concerning recently published advancements. First, many of these achievements consist solely of progress in pure mathematics. For instance, consider the recent Google paper featuring such a critical outcome that they chose to redact the theoretical quantum circuit to eliminate the risk of it being utilized to compromise essential cryptographic frameworks. This may appear to represent substantial momentum toward the future of CRQCs, but in reality, it altered nothing. Unless (or until) quantum hardware experiences its own Falcon 9 milestone, simply no hardware exists that approaches the stability and scale necessary to execute the redacted circuit. It is merely theater designed to obscure a layout intended for a machine that may never materialize. Second, looking at the hardware domain itself, we encounter numerous novel findings and incremental progress published annually, yet how many of these pertain to the identical quantum computing candidate technology? How many simply reflect starting over after a preceding avenue concluded in a dead end? The truth is that these milestones do not signify a linear progression toward ultimate triumph. They depict the breadth-first search of an infinite possibility space wherein quantum investigators are hoping to stumble upon a trajectory they can follow for even a brief stretch without encountering yet another blind alley.
Examining the actual outlook of quantum computing, the picture remains vague at best. Promising technical innovations certainly exist, particularly, in my view, within the realm of neutral atom devices. Nevertheless, it is far too premature to determine whether a viable route toward an ultimate CRQC exists along any current developmental path or if additional resets lie ahead. If, at some point, we witness numerous iterations of the same candidate hardware architecture successfully executing progressively sophisticated tasks, alongside computations of meaningful results that a gifted child cannot replicate, we can revisit this dialogue utilizing different empirical data.
In Theory
Two potential rationales exist for the persistent inability of quantum research to yield a CRQC across multiple decades. It is plausible that the challenge is simply immense, and we continue applying science and engineering to overcome it until human ingenuity triumphs eventually—just as it did with the creation of the internet, the smartphone, social media, and Bitcoin (leaving it to the reader to decide which of those represent positive advancements). Conversely, engineering a CRQC may be fundamentally impossible or destined to remain permanently out of reach. Consider the implications of a CRQC coming into existence: the device would need to maintain within its superposition a matrix of possibilities matching the complexity of the cryptographic problem requiring resolution. In other words, to break the 128-bit security level of the elliptic curve discrete logarithm on Bitcoin’s secp256k1 curve, the quantum superposition would have to capture every conceivable permutation of a 128-bit integer. Within classical computing, representing all such values would demand storage capacity exceeding the total volume ever manufactured by humanity by many orders of magnitude. If the quantum superposition possesses even the slightest granularity (meaning it fails to maintain absolute continuity across all potential values), the quantum computer can never achieve cryptographic relevance. If the energy required to sustain a superposition scales relative to the complexity of the modeled domain, a quantum computer can likewise never become cryptographically relevant. Modern interpretations of quantum physics do not invalidate either scenario.
Conclusion: Bitcoin Cannot Rest
Despite all the points outlined above, Bitcoin development geared toward novel cryptographic algorithms must persist. While a quantum assault on Bitcoin’s cryptography is by no means imminent, it remains entirely possible that alternative vulnerabilities could surface through different avenues. We recognize that specific elliptic curves have previously exhibited weaknesses, meaning secp256k1 could potentially be next. Bitcoin has endured for as long as it has because prior attacks on the network have served to harden it, and this dynamic will persist as the quantum FUD narrative plays out. The advancement of P2MR, P2TRv2, SHRINCS, SPHINCS, IBC, ML-DSA, alongside other post-quantum signature frameworks, will ultimately bolster Bitcoin’s fortification against prospective threats, even if an operational CRQC is never actually built.
This piece is featured in the latest Print edition of Bitcoin Magazine, The Quantum Issue. We’re sharing it here as an early look at the ideas explored throughout the full issue.
Originally published at https://bitcoinmagazine.com/print/the-quantum-issue-quantum-isnt-coming-for-your-bitcoin.
