7,907 research outputs found
Quantum Digital Signature based on Quantum One-way Functions
A quantum digital signature protocol based on quantum mechanics is proposed
in this paper. The security of the protocol relies on the existence of quantum
one-way functions by quantum information theorem. This protocol involves a
so-called arbitrator who validates and authenticates the signed message. In
this protocol, we use privacy key algorithm to ensure the security of quantum
information on channel and use quantum public keys to sign message. To
guarantee the authenticity of the message, a family of quantum stabilizer codes
are employed. Our protocol presents a novel method to construct ultimately
secure digital system in future secure communication.Comment: 9 pages, 1 tabl
Geometric dark energy traversable wormholes constrained by astrophysical observations
In this letter, we introduce the astrophysical observations into the wormhole
research, which is not meant to general parameters constraints for the dark
energy models, in order to understand more about in which stage of the universe
evolutions wormholes may exist through the investigation of the evolution
behavior of the cosmic equation of state parameter. As a concrete instance, we
investigate the Ricci dark energy (RDE) traversable wormholes constrained by
astrophysical data-sets. Particularly, we can discover from Fig. \ref{fig5} of
the present work, when the effective equation of state parameter ,
namely, the Null Energy conditions (NEC) is violated clearly, the wormholes
will appear (open). Subsequently, six specific solutions of static and
spherically symmetric traversable wormhole supported by the RDE are obtained.
Except for the case of constant redshift function, in which the solution is not
only asymptotically flat but also traversable, the remaining five solutions are
all not asymptotically flat, therefore, the exotic matter from the RDE fluids
is spatially distributed in the vicinity of the throat. Furthermore, we analyze
the physical characteristics and properties of the RDE traversable wormholes.
It is worth noting that, through the astrophysical observations, we get
constraints on the parameters of RDE model, explore the type of exotic RDE
fluids in different stages of the universe changing, limit the number of
available models for wormhole research, reduce the number of the wormholes
corresponding to different parameters for RDE model and provide a more apparent
picture for wormhole investigations from the new perspective of observational
cosmology backgroundComment: 17ps, 7fig
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