 Hello everyone, I'm Takashi from Entity and Kyo University. This is a short abstract video for our work, Quantum Commitments and Signatures Without One-Wing Functions. This is a joint work with Tomoyuki Morimai. Quantum information is awesome. One of the most surprising applications of quantum information in the context of cryptography is the quantum key distribution proposed by Bennett and Brassard in 1984. This is the information theory theory Secure Key Exchange Protocol using quantum communication. Information theory theory Secure Key Exchange is impossible in the classical world, so this changes the landscape of cryptography. After the invention of quantum key distribution, people expected that quantum communication can also be used to achieve information theoretical security for other cryptographic primitives. Unfortunately, however, it turns out that information theoretical security is impossible even with quantum communication for many cryptographic primitives, including symmetric and public key encryption, digital signatures, and commitments, etc. If information theoretical security is impossible, then the next natural question is what is the minimal assumption for these cryptographic primitives with quantum communication? In the classical world, it is known that the existence of one-way functions is the minimal assumption for essentially any non-trivial cryptographic functionality. So we would like to ask if this is the same in quantum cryptography. That is, are one-way functions necessary for these primitives with quantum communication? In this work, we show that one-way functions may not be needed for constructing commitments and one-time signatures with quantum communication. It is known that commitments imply general multi-party computations in the quantum setting, so this means that multi-party computations may also be constructed without one-way functions. To show this, we construct commitments and one-time signatures based on the primitive called pseudo-random quantum states, which are roughly a quantum analog of pseudo-random generators. Recently, Kretschmer showed that an evidence that pseudo-random quantum states do not imply the existence of one-way functions. More precisely, he showed an oracle relative to which pseudo-random quantum states exist, but BQP is equal to QMA, which in particular imply that no-way functions exist. Combining our constructions of commitments and one-time signatures from pseudo-random quantum states with the result of Kretschmer, we conclude that there is an oracle relative to which commitment and one-time signatures exist, but no-way functions exist. To take our message of this work is the following. One-way functions are not the minimal assumptions for quantum crypto. It is a fascinating future work to identify what is the minimal assumption for quantum crypto. For more details of our work, please check our paper or attend my talk at the first day of the conference. Thank you for watching.