{"id":2266,"date":"2026-04-07T10:20:30","date_gmt":"2026-04-07T08:20:30","guid":{"rendered":"https:\/\/www.milq.info\/?page_id=2266"},"modified":"2026-04-07T13:04:27","modified_gmt":"2026-04-07T11:04:27","slug":"myth2","status":"publish","type":"page","link":"https:\/\/www.milq.info\/en\/qti\/qmyths\/myth2\/","title":{"rendered":"Quantum Myths – Myth 2"},"content":{"rendered":"
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\nAdditionally, you are allowed to download the audio file. This way you can listen to it without an internet connection. Alternatively, you are allowed to listen it here on the website of course.<\/p>\n

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Download audio quantum myths course (female voice-over)<\/a><\/p>\n

Download audio quantum myths course (male voice-over)<\/a><\/p>\n

Download audio myth 2 (female voice-over) <\/a><\/p>\n

Download audio myth 2 (male voice-over) <\/a><\/p>\n

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Female voice-over:<\/h2>\n

Male voice-over:<\/h2>\n

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Myth #2:<\/strong> “Quantum computers can decrypt everything.”<\/h2>\n

The rapid progress in quantum computing has sparked both enthusiasm and concern, particularly in the field of cryptography. The question arose as to what impact a quantum computer would have and whether the security of all encrypted data could be maintained. This concerns everyone because we all want our data, communication channels, and documents to be encrypted and inaccessible to others. In this context, a myth has spread, claiming that quantum computers can decrypt everything. According to this, all forms of encrypted data would be decryptable, and our current security systems would be obsolete.<\/p>\n

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The Basis of the Myth<\/h3>\n

The myth primarily stems from the possibility that quantum computers might solve certain problems much faster than classical computers. One example is Shor’s Algorithm, which can efficiently factor large numbers and thus poses a significant threat to many cryptographic protocols. The security of many encryption methods, such as RSA, is based on the difficulty of factoring large numbers. A classical computer has little chance of decrypting them. However, a sufficiently powerful and fault-tolerant quantum computer could theoretically break these encryption methods and decrypt data that was previously considered secure. From these considerations arises the myth that quantum computers will be able to decrypt everything.<\/p>\n

Contrary to widespread belief, quantum computers do not have the ability to decrypt everything. Although fault-tolerant quantum computers could theoretically use Shor’s Algorithm to factor large numbers and break certain encryption protocols, it’s important to note that there are several crucial considerations to counter this issue.<\/p>\n

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Post-Quantum Cryptography<\/h3>\n

One of these considerations is the active pursuit of so-called post-quantum algorithms. Post-quantum algorithms are cryptographic algorithms considered secure against quantum computing’s potential. Post-quantum cryptography is unique because it involves classical approaches\u2014meaning it is not quantum cryptography but classical cryptography. This allows it to be used on our current systems without the need for any kind of quantum upgrade. Intensive research is underway to develop post-quantum algorithms for which no efficient quantum algorithm for decryption is currently known.<\/p>\n

Notable efforts in post-quantum cryptography include:<\/p>\n

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  • Lattice-based cryptography: This approach relies on the complexity of lattice problems, for which there are currently no efficient quantum solutions. Protocols like the Learning With Errors (LWE) problem are fundamental in this area.<\/li>\n
  • Hash-based cryptography: Techniques such as Merkle trees offer digital signatures deemed secure against quantum attacks.<\/li>\n
  • Code-based cryptography: McEliece and other code-based cryptographic systems rely on the difficulty of decoding random linear codes, another problem that quantum computers cannot solve efficiently.<\/li>\n
  • Multivariate quadratic polynomials: These involve solving systems of multivariate quadratic equations, which are also considered resistant to quantum attacks.<\/li>\n<\/ul>\n

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    Quantum-Secure Encryption Protocols<\/h3>\n

    Several quantum-secure encryption protocols have already been proposed and are being considered for standardization by organizations such as the National Institute of Standards and Technology (NIST). Notable protocols include:<\/p>\n

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    • NewHope protocol: NewHope is based on lattice problems and is an example of a key exchange algorithm that offers security against quantum attacks.<\/li>\n
    • Bit Flipping Key Encapsulation (BIKE) and Supersingular Isogeny Key Encapsulation (SIKE) protocol: BIKE and SIKE also offer mechanisms for secure key exchange in the presence of quantum threats; however, they do not rely on lattice problems but represent other approaches.<\/li>\n<\/ul>\n

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      Quantum Cryptography<\/h3>\n

      Quantum cryptography provides new ways to secure data. A prominent example is Quantum Key Distribution (QKD), which uses the principles of quantum mechanics to enable two parties to generate a shared random secret key used to encrypt and decrypt messages. The security of QKD relies on the fundamental principles of quantum mechanics, like superposition and entanglement, ensuring that any eavesdropping attempt is detectable.<\/p>\n

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      Overgeneralization by the Myth<\/h3>\n

      The deeper we delve into the subject, the quicker it becomes apparent that the belief that quantum computers can decrypt everything is an exaggerated overgeneralization. This myth seems to overlook several critical aspects:<\/p>\n

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      • Practical challenges: Building scalable, fault-tolerant quantum computers capable of efficiently executing algorithms like Shor presents enormous challenges to science. Current quantum computers are far from possessing the capabilities required for such tasks. It remains uncertain if and when such devices will be realized.<\/li>\n
      • Diverse encryption methods: Not all cryptographic methods are susceptible to quantum attacks. Symmetric key algorithms, such as AES (Advanced Encryption Standard), remain secure with adequately large keys. Quantum computers could reduce the time to break encryption using search algorithms like Grover’s. However, this is far less effective than Shor’s Algorithm, as Grover’s offers a quadratic speedup, while Shor’s offers an exponential speedup. AES would thus remain secure, assuming sufficiently large keys are used.<\/li>\n<\/ul>\n

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        Conclusion<\/h3>\n
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        • The notion that quantum computers can decrypt everything is simply an oversimplification.<\/li>\n
        • Ongoing research in post-quantum cryptography and the development of quantum-secure protocols pave the way for a secure future in a quantum age.<\/li>\n
        • The inherent difficulties in building advanced quantum computers also offer an additional layer of security, ensuring that our current cryptographic methods do not become obsolete overnight.<\/li>\n<\/ul>\n

          The proactive efforts of the cryptographic community ensure that we stay ahead of potential threats and maintain the confidentiality and integrity of our data in the face of advancing technology.<\/p>\n

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          Exercises:<\/h2>\n