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We investigate the degree to which impact in science and technology is associated with surprising breakthroughs, and how those breakthroughs arise. Identifying breakthroughs across science and technology requires models that distinguish surprising from expected advances at scale. Drawing on tens of millions of research papers and patents across the life sciences, physical sciences and patented inventions, and using a hypergraph model that predicts realized combinations of research contents (article keywords) and contexts (cited journals), here we show that surprise in terms of unexpected combinations of contents and contexts predicts outsized impact (within the top 10% of citations). These surprising advances emerge across, rather than within researchers or teams—most commonly when scientists from one field publish problem-solving results to an audience from a distant field. Our approach characterizes the frontier of science and technology as a complex hypergraph drawn from high-dimensional embeddings of research contents and contexts, and offers a measure of path-breaking surprise in science and technology.

 

Private Set Union (PSU) allows two players, the sender and the receiver, to compute the union of their input datasets with- out revealing any more information than the result. While it has found numerous applications in practice, not much re- search has been carried out so far, especially for large datasets. In this work, we take shuffling technique as a key to de- sign PSU protocols for the first time. By shuffling receiver’s set, we put forward the first protocol, denoted as ΠRPSU, that eliminates the expensive operations in previous works, such as additive homomorphic encryption and repeated operations on the receiver’s set. It outperforms the state-of-the-art design by Kolesnikov et al. (ASIACRYPT 2019) in both efficiency and security; the unnecessary leakage in Kolesnikov et al.’s design, can be avoided in our design. We further extend our investigation to the application sce- narios in which both players may hold unbalanced input datasets. We propose our second protocol ΠSPSU, by shuffling the sender’s dataset. This design can be viewed as a dual ver- sion of our first protocol, and it is suitable in the cases where the sender’s input size is much smaller than the receiver’s. Finally, we implement our protocols ΠRPSU and ΠSPSU in C++ on big datasets, and perform a comprehensive evaluation in terms of both scalability and parallelizability. The results demonstrate that our design can obtain a 4-5× improvement over the state-of-the-art by Kolesnikov et al. with a single thread in WAN/LAN settings. 

Private Set Union (PSU) allows two players, the sender and the receiver, to compute the union of their input datasets with- out revealing any more information than the result. While it has found numerous applications in practice, not much research has been carried out so far, especially for large datasets. In this work, we take shuffling technique as a key to design PSU protocols for the first time. By shuffling receiver’s set, we put forward the first protocol, denoted as $\Pi^R_{PSU}$, that eliminates the expensive operations in previous works, such as additive homomorphic encryption and repeated operations on the receiver’s set. It outperforms the state-of-the-art design by Kolesnikov et al. (ASIACRYPT 2019) in both efficiency and security; the unnecessary leakage in Kolesnikov et al.’s design, can be avoided in our design. We further extend our investigation to the application scenarios in which both players may hold unbalanced input datasets. We propose our second protocol $\Pi^S_{PSU}$, by shuffling the sender’s dataset. This design can be viewed as a dual version of our first protocol, and it is suitable in the cases where the sender’s input size is much smaller than the receiver’s. Finally, we implement our protocols $\Pi^R_{PSU}$ and $\Pi^S_{PSU}$ in C++ on big datasets, and perform a comprehensive evaluation in terms of both scalability and parallelizability. The results demonstrate that our design can obtain a 4-5X improvement over the state-of-the-art by Kolesnikov et al. with a single thread in WAN/LAN settings. 

Abstract It has been suggested that ion foreshock waves originating in the solar wind upstream of the quasi-parallel ( Q -||) shock can impact the planetary magnetosphere leading to standing shear Alfvén waves, i.e., the field line resonances (FLRs). In this paper, we carry out simulations of interaction between the solar wind and terrestrial magnetosphere under radial interplanetary magnetic field conditions by using a 3-D global hybrid model, and show the properties of self-consistently generated field line resonances through direct mode conversion in magnetospheric response to the foreshock disturbances for the first time. The simulation results show that the foreshock disturbances from the Q -|| shock can excite magnetospheric ultralow-frequency waves, among which the toroidal Alfvén waves are examined. It is found that the foreshock wave spectrum covers a wide frequency range and matches the band of FLR harmonics after excluding the Doppler shift effects. The fundamental harmonic of field line resonances dominates and has the strongest wave power, and the higher the harmonic order, the weaker the corresponding wave power. The nodes and anti-nodes of the odd and even harmonics in the equatorial plane are also presented. In addition, as the local Alfvén speed increases earthward, the corresponding frequency of each harmonic increases. The field-aligned current in the cusp region indicative of the possibly observable aurora is found to be a result of magnetopause perturbation which is caused by the foreshock disturbances, and a global view substantiating this scenario is given. Finally, it is found that when the solar wind Mach number decreases, the strength of both field line resonance and field-aligned current decreases accordingly.