It was a Friday evening in September and with no plan for the weekend, Zhang Xuan, a 25-year-old bank clerk, was lying in bed reading a book in his apartment in Beijing. He suddenly got the urge to go mountain hiking-...It was a Friday evening in September and with no plan for the weekend, Zhang Xuan, a 25-year-old bank clerk, was lying in bed reading a book in his apartment in Beijing. He suddenly got the urge to go mountain hiking-possibly influenced by the contents of the book on national geography.展开更多
Can the existence of “God” be calculated from known science and mathematics? We argue yes, provided the question is restricted to whether or not memory and consciousness are properties of spacetime. In this sense, w...Can the existence of “God” be calculated from known science and mathematics? We argue yes, provided the question is restricted to whether or not memory and consciousness are properties of spacetime. In this sense, we are seeking the god of Spinoza and Einstein, where the Universe is thought to be identical with divinity—but with the added characteristic of “awareness”. Currently, memory and consciousness and their relationship to spacetime and matter are of great interest to many prominent physicist, neurosurgeons, anesthesiologists, and philosophers. To show “Space-time Thinks,” we begin with a thought experiment formulated in 1867 by James Clerk Maxwell— together with Leó Szilárd’s discovery that memory and information are intimately related to the Second Law of Thermodynamics. Finally, we verify that memory and consciousness are properties of spacetime through an analogous Maxwell-Szilárd thought experiment associated with the creation of the God Particle—Higgs boson.展开更多
The digital signature is a very important subject for network security.Considering multiple signers and multiple verifiers,Xie and Yu(2004) pointed out that the multisignature scheme of Laih and Yen(1996) is vulnerabl...The digital signature is a very important subject for network security.Considering multiple signers and multiple verifiers,Xie and Yu(2004) pointed out that the multisignature scheme of Laih and Yen(1996) is vulnerable to a harmful attack.An attack can occur when a specified group of verifiers cooperate to forge a multisignature by secret key substitution following the leak of a secret key or by group public key adjustment during the process of renewing membership.Xie and Yu proposed an improvement of Laih and Yen's multisignature scheme.In this paper,we show that Xie and Yu's scheme is vulnerable to clerk and rogue-key attacks.We propose an improved multisignature scheme to resist such attacks.In the proposed scheme,multiple signers can generate a multisignature for the message with the signers' secret keys,and the specified group of verifiers can cooperate to verify the validity of the multisignature with the signers' public keys and the verifiers' secret key.The proposed scheme for a special verifier group not only has the advantages of Xie and Yu's scheme,but also is secure against clerk and rogue-key attacks.展开更多
文摘It was a Friday evening in September and with no plan for the weekend, Zhang Xuan, a 25-year-old bank clerk, was lying in bed reading a book in his apartment in Beijing. He suddenly got the urge to go mountain hiking-possibly influenced by the contents of the book on national geography.
文摘Can the existence of “God” be calculated from known science and mathematics? We argue yes, provided the question is restricted to whether or not memory and consciousness are properties of spacetime. In this sense, we are seeking the god of Spinoza and Einstein, where the Universe is thought to be identical with divinity—but with the added characteristic of “awareness”. Currently, memory and consciousness and their relationship to spacetime and matter are of great interest to many prominent physicist, neurosurgeons, anesthesiologists, and philosophers. To show “Space-time Thinks,” we begin with a thought experiment formulated in 1867 by James Clerk Maxwell— together with Leó Szilárd’s discovery that memory and information are intimately related to the Second Law of Thermodynamics. Finally, we verify that memory and consciousness are properties of spacetime through an analogous Maxwell-Szilárd thought experiment associated with the creation of the God Particle—Higgs boson.
基金supported in part by the National Science Council (Nos.NSC 97-2745-P-001-001-,NSC 98-2219-E-011-001-,NSC 98-2221-E-011-073-MY3,and NSC 98-2218-E-011-018-)
文摘The digital signature is a very important subject for network security.Considering multiple signers and multiple verifiers,Xie and Yu(2004) pointed out that the multisignature scheme of Laih and Yen(1996) is vulnerable to a harmful attack.An attack can occur when a specified group of verifiers cooperate to forge a multisignature by secret key substitution following the leak of a secret key or by group public key adjustment during the process of renewing membership.Xie and Yu proposed an improvement of Laih and Yen's multisignature scheme.In this paper,we show that Xie and Yu's scheme is vulnerable to clerk and rogue-key attacks.We propose an improved multisignature scheme to resist such attacks.In the proposed scheme,multiple signers can generate a multisignature for the message with the signers' secret keys,and the specified group of verifiers can cooperate to verify the validity of the multisignature with the signers' public keys and the verifiers' secret key.The proposed scheme for a special verifier group not only has the advantages of Xie and Yu's scheme,but also is secure against clerk and rogue-key attacks.
