The quantum one-time pad in the presence of an eavesdropper

A classical one-time pad allows two parties to send private messages over a public classical channel -- an eavesdropper who intercepts the communication learns nothing about the message. A quantum one-time pad is a shared quantum state which allows two parties to send private messages or private quantum states over a public quantum channel. If the eavesdropper intercepts the quantum communication she learns nothing about the message. In the classical case, a one-time pad can be created using shared and partially private correlations. Here we consider the quantum case in the presence of an eavesdropper, and find the single letter formula for the rate at which the two parties can send messages using a quantum one-time pad

RAMP: RDMA Migration Platform

Remote Direct Memory Access (RDMA) can be used to implement a shared storage abstraction or a shared-nothing abstraction for distributed applications. We argue that the shared storage abstraction is overkill for loosely coupled applications and that the shared-nothing abstraction does not leverage all the benefits of RDMA. In this thesis, we propose an alternative abstraction for such applications using a shared-on-demand architecture, and present the RDMA Migration Platform (RAMP). RAMP is a lightweight coordination service for building loosely coupled distributed applications. This thesis describes the RAMP system, its programming model and operations, and evaluates the performance of RAMP using microbenchmarks. Furthermore, we illustrate RAMPs load balancing capabilities with a case study of a loosely coupled application that uses RAMP to balance a partition skew under load

Letter from William Burke to James B. Finley

Burke writes concerning the case against him, which was pending before the Ohio Annual Conference, and on which Finley had been appointed to report. Finley evidently shared the report with Burke for his inspection. Burke approved the report and waited to learn the final action of the fall 1835 Annual Conference with regard to reinstatement of his membership. Since he has heard nothing, he now writes Finley to learn the final disposition of the case. He is an old man, and wants to depart at peace with all men. Abstract Number - 165https://digitalcommons.owu.edu/finley-letters/1163/thumbnail.jp

Evaluating the Impact of Data Placement to Spark and SciDB with an Earth Science Use Case

We investigate the impact of data placement for two Big Data technologies, Spark and SciDB, with a use case from Earth Science where data arrays are multidimensional. Simultaneously, this investigation provides an opportunity to evaluate the performance of the technologies involved. Two datastores, HDFS and Cassandra, are used with Spark for our comparison. It is found that Spark with Cassandra performs better than with HDFS, but SciDB performs better yet than Spark with either datastore. The investigation also underscores the value of having data aligned for the most common analysis scenarios in advance on a shared nothing architecture. Otherwise, repartitioning needs to be carried out on the fly, degrading overall performance

Multipartite Quantum Correlation and Communication Complexities

The concepts of quantum correlation complexity and quantum communication complexity were recently proposed to quantify the minimum amount of resources needed in generating bipartite classical or quantum states in the single-shot setting. The former is the minimum size of the initially shared state $\sigma$ on which local operations by the two parties (without communication) can generate the target state $\rho$, and the latter is the minimum amount of communication needed when initially sharing nothing. In this paper, we generalize these two concepts to multipartite cases, for both exact and approximate state generation. Our results are summarized as follows. (1) For multipartite pure states, the correlation complexity can be completely characterized by local ranks of sybsystems. (2) We extend the notion of PSD-rank of matrices to that of tensors, and use it to bound the quantum correlation complexity for generating multipartite classical distributions. (3) For generating multipartite mixed quantum states, communication complexity is not always equal to correlation complexity (as opposed to bipartite case). But they differ by at most a factor of 2. Generating a multipartite mixed quantum state has the same communication complexity as generating its optimal purification. But for correlation complexity of these two tasks can be different (though still related by less than a factor of 2). (4) To generate a bipartite classical distribution $P(x,y)$ approximately, the quantum communication complexity is completely characterized by the approximate PSD-rank of $P$. The quantum correlation complexity of approximately generating multipartite pure states is bounded by approximate local ranks.Comment: 19 pages; some typos are correcte

Quantum One-Time Pad in the Presence of an Eavesdropper

A classical one-time pad allows two parties to send private messages over a public classical channel—an eavesdropper who intercepts the communication learns nothing about the message. A quantum one-time pad is a shared quantum state which allows two parties to send private messages or private quantum states over a public quantum channel. If the eavesdropper intercepts the quantum communication she learns nothing about the message. In the classical case, a one-time pad can be created using shared and partially private correlations. Here we consider the quantum case in the presence of an eavesdropper, and find the single-letter formula for the rate at which the two parties can send messages using a general quantum state as a quantum one-time pad. Surprisingly, the formula coincides with the distillable entanglement assisted by a symmetric channel, an important quantity in quantum information theory, but which lacked a clear operational meaning

The quantum one-time pad in the presence of an eavesdropper

A classical one-time pad allows two parties to send private messages over a public classical channel—an eavesdropper who intercepts the communication learns nothing about the message. A quantum one-time pad is a shared quantum state which allows two parties to send private messages or private quantum states over a public quantum channel. If the eavesdropper intercepts the quantum communication she learns nothing about the message. In the classical case, a one-time pad can be created using shared and partially private correlations. Here we consider the quantum case in the presence of an eavesdropper, and find the single-letter formula for the rate at which the two parties can send messages using a general quantum state as a quantum one-time pad. Surprisingly, the formula coincides with the distillable entanglement assisted by a symmetric channel, an important quantity in quantum information theory, but which lacked a clear operational meaning

Communication Complexity of Private Simultaneous Quantum Messages Protocols

The private simultaneous messages (PSM) model is a non-interactive version of the multiparty secure computation (MPC), which has been intensively studied to examine the communication cost of the secure computation. We consider its quantum counterpart, the private simultaneous quantum messages (PSQM) model, and examine the advantages of quantum communication and prior entanglement of this model. In the PSQM model, $k$ parties $P_1,\ldots,P_k$ initially share a common random string (or entangled states in a stronger setting), and they have private classical inputs $x_1,\ldots, x_k$. Every $P_i$ generates a quantum message from the private input $x_i$ and the shared random string (entangled states), and then sends it to the referee $R$. Receiving the messages from the $k$ parties, $R$ computes $F(x_1,\ldots,x_k)$ from the messages. Then, $R$ learns nothing except for $F(x_1,\ldots,x_k)$ as the privacy condition. We obtain the following results for this PSQM model. ($i$) We demonstrate that the privacy condition inevitably increases the communication cost in the two-party PSQM model as well as in the classical case presented by Applebaum, Holenstein, Mishra, and Shayevitz [Journal of Cryptology 33(3), 916--953 (2020)]. In particular, we prove a lower bound $(3-o(1))n$ of the communication complexity in PSQM protocols with a shared random string for random Boolean functions of $2n$-bit input, which is larger than the trivial upper bound $2n$ of the communication complexity without the privacy condition. ($ii$) We demonstrate a factor two gap between the communication complexity of PSQM protocols with shared entangled states and with shared random strings by designing a multiparty PSQM protocol with shared entangled states for a total function that extends the two-party equality function. ($iii$) We demonstrate an exponential gap between the communication complexity of PSQM protocols with shared entangled states and with shared random strings for a two-party partial function

Chapter 7 Conclusion

The notion that photographs are the products of biases and hidden agendas is nothing new. Photographs have presented Argentina’s Proceso as a source of peace and stability, Canada’s residential schools as agents of successful assimilation and the Extraordinary Chambers in the Courts of Cambodia as an unimpeachable force for justice. Photography has proven a valuable partner in these endeavours. Photographs provide evocative visual, temporal and material links to the past that allow them to be used as evidence, affirmations of different types of truth, political critique, and individual and shared historical narratives. Contemporary patterns of international photography education, exhibition, theorization and publication reaffirm the critical necessity of bringing a deterritorialized perspective to national case studies. Contemporary photographers are deterritorializing their responses to human rights abuses by forging connections between different historical events across time and space