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  1. Free, publicly-accessible full text available July 29, 2025
  2. Abstract

    We present new cosmological parameter constraints from the eBOSS Lyman-α forest survey. We use a new theoretical model and likelihood based on the PRIYA simulation suite. PRIYA is the first suite to resolve the Lyman-αforest in a (120 Mpc/h)3volume, using a multi-fidelity emulation technique. We use PRIYA to predict Lyman-αforest observables with ≲ 1% interpolation error over an 11 dimensional (9 simulated, 2 in post-processing) parameter space. We identify an internal tension within the flux power spectrum data. Once the discrepant data is removed, we find the primeval scalar spectral index measured at a pivot scale ofk0= 0.78 Mpc-1to benP= 1.009+0.027-0.018at 68% confidence. This measurement from the Lyman-αforest flux power spectrum alone is in reasonable agreement with Planck, and in tension with earlier eBOSS analyses. The amplitude of matter fluctuations isσ8= 0.733+0.026-0.029at 68% confidence, in agreement with Dark Energy Survey weak lensing measurements and other small-scale structure probes and in tension with CMB measurements from Planck and ACT. The effective optical depth to Lyman-α  photons from our pipeline is in good agreement with earlier high resolution measurements. We find a linear power atz= 3 andk= 0.009 s/km of Δ2L= 0.302+0.024-0.027with a slopeneff= -2.264+0.026-0.018. Our flux power spectrum only chains prefer a low level of heating during helium reionization. When we add IGM temperature data we findnP= 0.983 ± 0.020 andσ8= 0.703+0.023-0.027. Our chains prefer an early and long helium reionization event, as suggested by measurements from the helium Lyman-αforest. In the near future we will use our pipeline to infer cosmological parameters from the DESI Lyman-α data.

     
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    Free, publicly-accessible full text available July 1, 2025
  3. Domain Name System Security Extensions (DNSSEC) uses public-key digital signatures to provide integrity and authentication for DNS query responses. The current standardized DNS for reliable UDP delivery limits DNS response (including the message, signature, and public key) to a maximum of 1232 bytes. Incorporating NIST’s post-quantum digital signatures into the DNS protocol results in a response size that exceeds the limit set by the Ethernet standardization, making PQC incompatible with the current standardized DNS. To address the incompatibility and enable PQC to protect the authenticity against the quantum-equipped adversaries, previous research proposed fragmenting the DNSSEC messages. Fragmentation however exposes DNSSEC to Fragmentation Mis-Association threat, traditionally studied in the broader IP fragmentation contexts and not applicable in the current DNSSEC with classical/pre-quantum cipher (no fragmentation needed). We distinguish our work from the previous research incorporating PQC to DNSSEC to defend against the Fragmentation Mis- Association Threat by chaining the fragments and applying cryptographic commit-and-reveal. We also advance the previous research and further reduce the number of packet fragments, which can be particularly useful as the DNSSEC based on UDP is prone to packet transmission failure increasing the chance of the DNS response failure when sent in multiple fragments, by using blockchain to offload and enable the offline delivery of the public key. Our scheme thus even allows the Falcon-512 PQC cipher incorporation to forgo the fragmentation, in contrast to the previous research requiring fragmentation for Falcon-512; the other PQC ciphers, i.e., Dilithium ciphers and Falcon-1024, still require fragmentation in our scheme due to the standardized signature sizes. We implement our scheme and analyze the effectiveness and performances through experimentation. 
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    Free, publicly-accessible full text available June 9, 2025
  4. Cryptocurrency is designed for anonymous financial transactions to avoid centralized control, censorship, and regulations. To protect anonymity in the underlying P2P networking, Bitcoin adopts and supports anonymous routing of Tor, I2P, and CJDNS. We analyze the networking performances of these anonymous routing with the focus on their impacts on the blockchain consensus protocol. Compared to non-anonymous routing, anonymous routing adds inherent-by-design latency performance costs due to the additions of the artificial P2P relays. However, we discover that the lack of ecosystem plays an even bigger factor in the performances of the anonymous routing for cryptocurrency blockchain. I2P and CJDNS, both advancing the anonymous routing beyond Tor, in particular lack the ecosystem of sizable networking-peer participation. I2P and CJDNS thus result in the Bitcoin experiencing networking partitioning, which has traditionally been researched and studied in cryptocurrency/blockchain security. We focus on I2P and Tor and compare them with the non-anonymous routing because CJDNS has no active public peers resulting in no connectivity. Tor results in slow propagation while I2P yields soft partition, which is a partition effect long enough to have a substantial impact in the PoW mining. To better study and identify the latency and the ecosystem factors of the cryptocurrency networking and consensus costs, we study the behaviors both in the connection manager (directly involved in the P2P networking) and the address manager (informing the connection manager of the peer selections on the backend). This paper presents our analyses results to inform the state of cryptocurrency blockchain with anonymous routing and discusses future work directions and recommendations to resolve the performance and partition issues. 
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    Free, publicly-accessible full text available May 27, 2025
  5. We study the impact of induced correlations and quasiparticle properties by immersing two distinguishable impurities in a harmonically trapped bosonic medium. It is found that when the impurities couple both either repulsively or attractively to their host, the latter mediates a two-body correlated behavior between them. In the reverse case, namely the impurities interact oppositely with the host, they feature anti-bunching. Monitoring the impurities relative distance and constructing an effective two-body model to be compared with the full many-body calculations, we are able to associate the induced (anti-) correlated behavior of the impurities with the presence of attractive (repulsive) induced interactions. Furthermore, we capture the formation of a bipolaron and a trimer state in the strongly attractive regime. The trimer refers to the correlated behavior of two impurities and a representative atom of the bosonic medium and it is characterized by an ellipsoidal shape of the three-body correlation function. Our results open the way for controlling polaron induced correlations and creating relevant bound states.

     
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  6. Abstract

    Primordial black holes (PBHs) could explain some fraction of dark matter and shed light on many areas of early-Universe physics. Despite over half a century of research interest, a PBH population has so far eluded detection. The most competitive constraints on the fraction of dark matter comprised of PBHs (fDM) in the (10−9–10)Mmass ranges come from photometric microlensing and boundfDM≲ 10−2–10−1. With the advent of the Roman Space Telescope with its submilliarcsecond astrometric capabilities and its planned Galactic Bulge Time Domain Survey (GBTDS), detecting astrometric microlensing signatures will become routine. Compared with photometric microlensing, astrometric microlensing signals are sensitive to different lens masses–distance configurations and contain different information, making it a complimentary lensing probe. At submilliarcsecond astrometric precision, astrometric microlensing signals are typically detectable at larger lens–source separations than photometric signals, suggesting a microlensing detection channel of pure astrometric events. We use a Galactic simulation to predict the number of detectable microlensing events during the GBTDS via this pure astrometric microlensing channel. Assuming an absolute astrometric precision floor for bright stars of 0.1 mas for the GBTDS, we find that the number of detectable events peaks at ≈103fDMfor a population of 1MPBHs and tapers to ≈10fDMand ≈100fDMat 10−4Mand 103M, respectively. Accounting for the distinguishability of PBHs from stellar lenses, we conclude the GBTDS will be sensitive to a PBH population atfDMdown to ≈10−1–10−3for (10−1–102)Mlikely yielding novel PBH constraints.

     
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    Free, publicly-accessible full text available April 1, 2025