A delegateable signature scheme (DSS) which was first introduced by Barak is mainly based on the non-interactive zero-knowledge proof (NIZK) for preventing the signing verifier from telling which witness (i.e., r...A delegateable signature scheme (DSS) which was first introduced by Barak is mainly based on the non-interactive zero-knowledge proof (NIZK) for preventing the signing verifier from telling which witness (i.e., restricted subset) is being used. However, the scheme is not significantly efficient due to the difficulty of constructing NIZK. We first show that a non-interactive witness indistinguishable (NlWl) proof system and a non-interactive witness hiding (NIWH) proof system are easier and more efficient proof models than NIZK in some cases. Furthermore, the witnesses em- ployed in these two protocols (NlWl and NIWT) cannot also be distinguished by the verifiers. Combined with the E-protocol, we then construct NlWl and NIWH proofs for any NP statement under the existence of one-way functions and show that each proof is different from those under the existence of trapdoor permutations, Finally, based on our NlWl and NIWH proofs, we construct delegateable signature schemes under the existence of one-way functions, which are more efficient than Barak's scheme under the existence of trapdoor permutations.展开更多
The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no in...The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no inner structures and with properties assigned by declaration. Such view is in conflict with the observed vacuum energy density, 140 orders of magnitudes less than required by the QFT. In addition, such view is challenged by Aphysical Quantum Mechanics (AQM), a deeper quantum theory. According to AQM, the fundamental understanding of quantum reality is expanded by the addition of two fundamental categories, aphysical and elementary consciousness of elementary particles. Based on AQM and as an example, the total ontology of the intrinsic (fundamental) electron is presented with its inner structure of perfect geometry consisting of the physical charged c-ring and aphysical cylinder, and with its properties such as self-mass, spin, magneto-electrostatic field configuration and magnetic moment. The position parameter in the inner structure demonstrates that there are no two identical intrinsic electrons in the Universe thus placing a question mark over the QFT principle of indistinguishability.展开更多
This paper shows that the protocol presented by Goyal et al. can be further simplified for a one-way function, with the simplified protocol being more practical for the decisional Diffie-Hellman assumption. Goyal et a...This paper shows that the protocol presented by Goyal et al. can be further simplified for a one-way function, with the simplified protocol being more practical for the decisional Diffie-Hellman assumption. Goyal et al. provided a general transformation from any honest verifier statistical zero-knowledge argument to a concurrent statistical zero-knowledge argument. Their transformation relies only on the existence of one-way functions. For the simplified transformation, the witness indistinguishable proof of knowledge protocols in "parallel" not only plays the role of preamble but also removes some computational zero-knowledge proofs, which Goyal et al. used to prove the existence of the valid openings to the commitments. Therefore, although some computational zero-knowledge proofs are replaced with a weaker notion, the witness indistinguishable protocol, the proof of soundness can still go through.展开更多
This paper focuses on the instantiation of random oracles in public key encryption schemes. A misunderstanding in the former instantiations is pointed out and analyzed. A method of using this primitive as a substituti...This paper focuses on the instantiation of random oracles in public key encryption schemes. A misunderstanding in the former instantiations is pointed out and analyzed. A method of using this primitive as a substitution of random oracles is also proposed. The partial and full instantiations of random oracles in optimal asymmetric encryption padding (OAEP) implemented by pseudorandom functions are described and the resulted schemes are proven to be indistinguishable secure against adaptive chosen ciphertext attack (IND-CCA2) secure. Using this method, one can transform a practical public key encryption scheme secure in the random oracle model into a standard-model secure scheme. The security of the scheme is based on computational assumptions, which is weaker than decisional assumptions used in Cramer- Shoup like schemes.展开更多
We report the observed photon bunching statistics of biexciton cascade emission at zero time delay in single quantum dots by second-order correlation function g(2) (T) measurements under continuous wave excitation...We report the observed photon bunching statistics of biexciton cascade emission at zero time delay in single quantum dots by second-order correlation function g(2) (T) measurements under continuous wave excitation. It is found that the bunching phenomenon is independent of the biexciton binding energy when it varies from 0.59 meV to nearly zero. The photon bunching takes place when the exeiton photon is not spectrally distinguishable from the biexciton photon, and either of them can trigger the %tart' in a Hanbury-Brown and Twiss setup. However, if the exciton energy is spectrally distinguishable from the biexciton, the photon statistics will become asymmetric and a cross-bunching lineshape can be obtained. The theoretical calculations based on a model of three-level rate-equation analysis are consistent with the result of g(2)(τ) correlation function measurements.展开更多
∑-protocol has been proved to be a very powerful cryptographic tool and widely used in nnmerous important cryptographic applications. In this paper, the authors make use of ∑-protocol as a main tool to resolve the f...∑-protocol has been proved to be a very powerful cryptographic tool and widely used in nnmerous important cryptographic applications. In this paper, the authors make use of ∑-protocol as a main tool to resolve the following difficult problems 1-3 and to construct three ettlcient cryptographic protocols 4 6:1) How to construct a protocol for proving a secret integer to be a Blum integer with form PQ, where P, Q are two different primes and both -- 3(mod 4);2) How to construct a protocol for proving a secret polynomial with exact degree t - 1 iil a (t, n)- threshold secret sharing scheme:3) How to construct witness indistinguishable and witness hiding protocol not from zero-knowledge proof;4) A publicly verifiable secret sharing scheme with information-theoretic security;5) A delegateable signature scheme under the existence of one-way permutations;6) Non-interactive universal designated verifier signature schemes.展开更多
基金Supported partially by the National Natural Science Foundation of China(Grant Nos.90604034,10371127 and 10671114)
文摘A delegateable signature scheme (DSS) which was first introduced by Barak is mainly based on the non-interactive zero-knowledge proof (NIZK) for preventing the signing verifier from telling which witness (i.e., restricted subset) is being used. However, the scheme is not significantly efficient due to the difficulty of constructing NIZK. We first show that a non-interactive witness indistinguishable (NlWl) proof system and a non-interactive witness hiding (NIWH) proof system are easier and more efficient proof models than NIZK in some cases. Furthermore, the witnesses em- ployed in these two protocols (NlWl and NIWT) cannot also be distinguished by the verifiers. Combined with the E-protocol, we then construct NlWl and NIWH proofs for any NP statement under the existence of one-way functions and show that each proof is different from those under the existence of trapdoor permutations, Finally, based on our NlWl and NIWH proofs, we construct delegateable signature schemes under the existence of one-way functions, which are more efficient than Barak's scheme under the existence of trapdoor permutations.
文摘The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no inner structures and with properties assigned by declaration. Such view is in conflict with the observed vacuum energy density, 140 orders of magnitudes less than required by the QFT. In addition, such view is challenged by Aphysical Quantum Mechanics (AQM), a deeper quantum theory. According to AQM, the fundamental understanding of quantum reality is expanded by the addition of two fundamental categories, aphysical and elementary consciousness of elementary particles. Based on AQM and as an example, the total ontology of the intrinsic (fundamental) electron is presented with its inner structure of perfect geometry consisting of the physical charged c-ring and aphysical cylinder, and with its properties such as self-mass, spin, magneto-electrostatic field configuration and magnetic moment. The position parameter in the inner structure demonstrates that there are no two identical intrinsic electrons in the Universe thus placing a question mark over the QFT principle of indistinguishability.
基金Supported by the National Key Basic Research and Development(973) Program of China(No.2007CB807902)the National Natural Science Foundation of China(Nos.90604036 and 60525201)
文摘This paper shows that the protocol presented by Goyal et al. can be further simplified for a one-way function, with the simplified protocol being more practical for the decisional Diffie-Hellman assumption. Goyal et al. provided a general transformation from any honest verifier statistical zero-knowledge argument to a concurrent statistical zero-knowledge argument. Their transformation relies only on the existence of one-way functions. For the simplified transformation, the witness indistinguishable proof of knowledge protocols in "parallel" not only plays the role of preamble but also removes some computational zero-knowledge proofs, which Goyal et al. used to prove the existence of the valid openings to the commitments. Therefore, although some computational zero-knowledge proofs are replaced with a weaker notion, the witness indistinguishable protocol, the proof of soundness can still go through.
基金Supported by the National Basic Research Program of China (973 Program) (2007CB311201)the National High-Technology Research and Development Program of China (863 Program) (2006AA01Z427)the National Natural Science Foundation of China (60673073)
文摘This paper focuses on the instantiation of random oracles in public key encryption schemes. A misunderstanding in the former instantiations is pointed out and analyzed. A method of using this primitive as a substitution of random oracles is also proposed. The partial and full instantiations of random oracles in optimal asymmetric encryption padding (OAEP) implemented by pseudorandom functions are described and the resulted schemes are proven to be indistinguishable secure against adaptive chosen ciphertext attack (IND-CCA2) secure. Using this method, one can transform a practical public key encryption scheme secure in the random oracle model into a standard-model secure scheme. The security of the scheme is based on computational assumptions, which is weaker than decisional assumptions used in Cramer- Shoup like schemes.
基金Supported by the National Key Basic Research Program of China under Grant No 2013CB922304the National Natural Science Foundation of China under Grant Nos 11474275 and 11464034
文摘We report the observed photon bunching statistics of biexciton cascade emission at zero time delay in single quantum dots by second-order correlation function g(2) (T) measurements under continuous wave excitation. It is found that the bunching phenomenon is independent of the biexciton binding energy when it varies from 0.59 meV to nearly zero. The photon bunching takes place when the exeiton photon is not spectrally distinguishable from the biexciton photon, and either of them can trigger the %tart' in a Hanbury-Brown and Twiss setup. However, if the exciton energy is spectrally distinguishable from the biexciton, the photon statistics will become asymmetric and a cross-bunching lineshape can be obtained. The theoretical calculations based on a model of three-level rate-equation analysis are consistent with the result of g(2)(τ) correlation function measurements.
基金supported by the Foundation of tihe National Natural Science of China under Grant Nos 90604034 (Key Project), 10726012, 10871222, 10531040,and 10471156
文摘∑-protocol has been proved to be a very powerful cryptographic tool and widely used in nnmerous important cryptographic applications. In this paper, the authors make use of ∑-protocol as a main tool to resolve the following difficult problems 1-3 and to construct three ettlcient cryptographic protocols 4 6:1) How to construct a protocol for proving a secret integer to be a Blum integer with form PQ, where P, Q are two different primes and both -- 3(mod 4);2) How to construct a protocol for proving a secret polynomial with exact degree t - 1 iil a (t, n)- threshold secret sharing scheme:3) How to construct witness indistinguishable and witness hiding protocol not from zero-knowledge proof;4) A publicly verifiable secret sharing scheme with information-theoretic security;5) A delegateable signature scheme under the existence of one-way permutations;6) Non-interactive universal designated verifier signature schemes.