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While differentially private synthetic data generation has been explored extensively in the literature, how to update this data in the future if the underlying private data changes is much less understood. We propose an algorithmic framework for streaming data that generates multiple synthetic datasets over time, tracking changes in the underlying private data. Our algorithm satisfies differential privacy for the entire input stream (continual differential privacy) and can be used for high-dimensional tabular data. Furthermore, we show the utility of our method via experiments on real-world datasets. The proposed algorithm builds upon a popular select, measure, fit, and iterate paradigm (used by offline synthetic data generation algorithms) and private counters for streams.

This work introduces a Strategic Pseudo-Goal Perturbation (SPGP) technique, a novel approach to resolve deadlock situations in multi-agent navigation scenarios. Leveraging the robust framework of Safety Barrier Certificates, our method integrates a strategic perturbation mechanism that guides agents through social mini-games where deadlock and collision occur frequently. The method adopts a strategic calculation process where agents, upon encountering a deadlock select a pseudo goal within a predefined radius around the current position to resolve the deadlock among agents. The calculation is based on controlled strategic algorithm, ensuring that deviation towards pseudo-goal is both purposeful and effective in resolution of deadlock. Once the agent reaches the pseudo goal, it resumes the path towards the original goal, thereby enhancing navigational efficiency and safety. Experimental results demonstrates SPGP's efficacy in reducing deadlock instances and improving overall system throughput in variety of multi-agent navigation scenarios.

Heavy meson decays with missing energy in the final state offer interesting avenues to search for light invisible new physics such as dark matter (DM). In this context, we show that such NP interactions also affect lifetime difference in neutral meson-antimeson mixing. We consider general dimension-six effective quark interactions involving a pair of DM particles and calculate their contributions to lifetime difference in beauty and charm meson systems. We use the latest data on mixing observables to constrain the relevant effective operators. We find that lifetime differences provide novel and complementary flavor constraints compared to those obtained from heavy meson decays., Comment: 18 pages, 5 captioned figures, 1 table

Much of the research in differential privacy has focused on offline applications with the assumption that all data is available at once. When these algorithms are applied in practice to streams where data is collected over time, this either violates the privacy guarantees or results in poor utility. We derive an algorithm for differentially private synthetic streaming data generation, especially curated towards spatial datasets. Furthermore, we provide a general framework for online selective counting among a collection of queries which forms a basis for many tasks such as query answering and synthetic data generation. The utility of our algorithm is verified on both real-world and simulated datasets.

Baryon asymmetry of the Universe offers one of the strongest hints for physics Beyond the Standard Model (BSM). Remarkably, in the general two Higgs Doublet Model (g2HDM) that possesses a second set of Yukawa matrices, one can have electroweak baryogenesis (EWBG) while the electron electric dipole moment (eEDM) is evaded by a natural flavor tuning that echoes SM. We show that eEDM may first emerge around $10^{-30}\,e$ cm or so, followed by neutron EDM (nEDM) down to $10^{-27}\,e$ cm. We illustrate a cancellation mechanism for nEDM itself, which in turn can be probed when a facility capable of pushing down to $10^{-28}\,e$ cm becomes available., Comment: 4 pages, 4 labeled figures

With the Large Hadron Collider (LHC) running, we should probe electroweak baryogenesis (EWBG) while probing $CP$ violation (CPV) with electron electric dipole moment (eEDM). Rooted in the flavor structure of the Standard Model (SM), the general two Higgs doublet model (g2HDM) with a second set of Yukawa couplings can deliver EWBG while surviving eEDM. We point out a chiral-enhanced top-bottom interference effect that makes $b \to s\gamma$ decay an exquisite window on EWBG and eEDM, and illustrate the importance of the $\Delta A_{CP}$ observable at Belle II., Comment: 5 pages, 3 captioned figures, 1 table, v3: added results for inclusive CPV difference $\Delta A_{CP}$

Current data on semileptonic charged- and neutral-current $B$ decays show deviations from the predictions of the Standard Model. It is well known that a charged Higgs boson, belonging to the two-Higgs doublet model without $Z_2$ symmetry, offers one of the simplest solution to the charged-current $B$ decays. We show that this solution naturally induces a negative shift of $\mathcal{O}(1)$ in the Wilson coefficient ($C_{9\ell}$) of operator $(\bar s_L\gamma_\mu b_L)(\bar \ell\gamma^\mu \ell)$, potentially resolving the tension in neutral-current $B$ decays as well. Interestingly, the lepton universality ratios in $b\to s \ell^+\ell^-$ decays, in tune with the recent LHCb result, remain SM-like. Precision constraints from neutral $B$ and $K$ meson mixing, decays $B_c\to \tau\bar\nu$, $B\to X_s\gamma$, and leptonic decays of $\tau$ and $Z$ can be satisfied. Furthermore, a positive shift in $W$-boson mass, nicely in agreement with the CDF measurement, is also possible, requiring the neutral scalars to be heavier than the charged Higgs but within the sub-TeV region., Comment: 11 pages, 2 captioned figures, extended discussion in sec III.A and IV, and added an appendix; matches published version

We investigate the possible sizes of all the CP-violating asymmetries offered by the angular distribution of rare decay $\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^-$ in the Standard Model and new physics scenarios motivated by the recent $b\to s \ell^+\ell^-$ anomalies. We work in a model-independent effective theory framework and discuss the sensitivity of CP asymmetries to new ${O}_{9,10}$ operators and their chirality flipped counterparts. We find that the size of many of the CP asymmetries can be at the level of a few percent in new physics scenarios consistent with current $b\to s\ell^+\ell^-$ data at a level of $1\sigma$. We emphasize that measurements of these CP asymmetries can be used to discriminate different new physics scenarios in $b\to s \ell^+\ell^-$., Comment: 28 pages, 4 captioned figures; updated NP benchmarks following the latest RK(*) measurements; matches journal version

We discuss new physics (NP) contributions to kaon mixing parameter $\varepsilon_K$, direct CP violation parameter $\varepsilon^\prime/\varepsilon$ of $K\to \pi\pi$, and rare decays $K^+\to \pi^+\nu\bar\nu$, $K_L\to \pi^0\nu\bar\nu$ and $K_{L, S}\to \mu^+ \mu^- $ in the context of general two Higgs doublet model. We focus on contributions of top quark related exotic couplings, and show that simultaneous presence of flavor conserving and flavor violating interactions can lead to large NP effects in kaon sector, while being consistent with the stringent constraints from B physics observables such as $B_{s(d)}$-$\bar B_{s(d)}$ mixing, $B_s\to \mu^+ \mu^-$, and $b\to s\gamma$. We stress on the importance of correlations between $\varepsilon_K$, $K^+\to \pi^+\nu\bar\nu$ and $B_s\to \mu^+ \mu^-$ that can be exploited to distinguish the parameter space corresponding to a light (sub-TeV) or heavy (TeV) scale charged Higgs boson., Comment: Talk given at the KAON 2022 conference, September 13-16, 2022, Osaka (Japan); submission to Journal of Physics: Conference Series

Privacy concerns have attracted increasing attention in data-driven products due to the tendency of machine learning models to memorize sensitive training data. Generating synthetic versions of such data with a formal privacy guarantee, such as differential privacy (DP), provides a promising path to mitigating these privacy concerns, but previous approaches in this direction have typically failed to produce synthetic data of high quality. In this work, we show that a simple and practical recipe in the text domain is effective: simply fine-tuning a pretrained generative language model with DP enables the model to generate useful synthetic text with strong privacy protection. Through extensive empirical analyses on both benchmark and private customer data, we demonstrate that our method produces synthetic text that is competitive in terms of utility with its non-private counterpart, meanwhile providing strong protection against potential privacy leakages., Comment: ACL 2023 Main Conference (Honorable Mention)

We study lepton flavor violating (LFV) $B$ decays in a general two Higgs doublet model with sub-TeV exotic scalars. Two different parameter spaces are explored: one dominated by extra top Yukawa coupling $\rho_{tt}$, the other by LFV couplings relevant for the muon $g-2$ anomaly. In the first case, flavor constraints such as $\ell \to \ell^\prime\gamma$, $h \to \ell\ell^\prime$ imply LFV $B$ decays are far below experimental sensitivities. The second case needs to be close to the alignment limit, but $B_q \to \tau\mu$ and $B \to (K, \pi) \tau\mu$ rates can lie within the sensitivities of Belle II and LHCb Upgrade II. Neutral $B$ meson mixings and $B,\, K,\, \pi \to \ell \nu$ decays provide important flavor constraints on parameter space. $B$ decays involving $e$-$\tau$ violation are constrained by $\mu\to e$ processes., Comment: 11 pages, 6 captioned figures, added a discussion of collider signatures in section IV and included a new appendix; matches published version

In the general two Higgs doublet model (g2HDM) that has extra Yukawa couplings, we analyze their New Physics (NP) contributions to kaon mixing parameter $\varepsilon_K$, direct CP violation parameter $\varepsilon^\prime/\varepsilon$, and rare $K^+ \to \pi^+\nu\bar\nu$, $K_L \to \pi^0\nu\bar\nu$, and $K_{L, S} \to \mu^+ \mu^-$ decays. We study correlations between these observables, and call special attention to a unique complementarity of kaon mixing and rare $K\to \pi \nu\bar\nu$ decays in probing the exotic Higgs mass spectrum of g2HDM. The importance of kaon physics in probing NP vis-\`a-vis B physics is stressed. One unexpected feature we uncover is the special sensitivity of $K^+ \to \pi^+\nu\bar\nu$ to TeV scale charged Higgs boson., Comment: 26 pages, 10 captioned figures; v2: fixed typos; v3: added a brief discussion in section 5 about NP effects of down-type flavor violation. Accepted for publication in JHEP

In a two Higgs doublet model with extra Yukawa couplings, we assess the new physics contributions to charged lepton electric dipole moment. We focus especially on muon (and tau) EDM where in the coming decade several experiments $-$ Muon g-2, J-PARC and PSI (and Belle II) $-$ will push sensitivities down by several orders of magnitude. With the working assumption that extra Yukawa couplings are analogous to SM ones in strength and taking exotic scalar masses in sub-TeV range, we find that $\mu$ and $\tau$ EDM can be enhanced to values larger than new physics scenarios that scale with lepton mass. The main effect comes from the flavor-conserving extra top coupling $\rho_{tt}$ via well-known two-loop diagrams. Deviating from our working assumption, if the muon $g-2$ anomaly arises from the one-loop diagram, driven by singly enhanced lepton flavor violating $\rho_{\tau\mu}$ coupling, it can also induce rather large muon EDM, accessible at upcoming experiments., Comment: 9 pages, 5 captioned figures; matches journal version

The recent confirmation of the muon $g-2$ anomaly by the Fermilab g-2 experiment may harbinger a new era in $\mu$ and $\tau$ physics. In the context of general two Higgs doublet model, the discrepancy can be explained via one-loop exchange of sub-TeV exotic scalar and pseudoscalars, namely $H$ and $A$, that have flavor changing neutral couplings $\rho_{\tau\mu}$ and $\rho_{\mu\tau}$ at $\sim 20$ times the usual tau Yukawa coupling, $\lambda_\tau$. Taking $\rho_{\ell\ell^\prime}\sim \lambda_{ \rm min(\ell, \ell^\prime)}$, we show that the above solution to muon $g-2$ then predicts enhanced rates of various charged lepton flavor violating processes, which should be accessible at upcoming experiments. We cover muon related processes such as $\mu \to e \gamma$, $\mu \to eee$ and $\mu N \to e N$, and $\tau$ decays $\tau \to \mu \gamma$ and $\tau \to \mu\mu\mu$. A similar one-loop diagram with $\rho_{e\tau}= \rho_{\tau e} = {\cal O}(\lambda_e)$ induces $\mu \to e\gamma$, bringing the rate right into the sensitivity of the MEG~II experiment. The $\mu e\gamma$ dipole can be probed further by $\mu \to 3e$ and $\mu N \to e N$. With its promised sensitivity range and ability to use different nuclei, the $\mu N \to eN$ conversion experiments can not only make discovery, but access the extra diagonal quark Yukawa couplings $\rho_{qq}$. For the $\tau$ lepton, we find that $\tau \to \mu\gamma$ would probe $\rho_{\tau\tau}$ down to $\lambda_\tau$ or lower, while $\tau \to 3\mu$ would probe $\rho_{\mu\mu}$ to ${\cal O}(\lambda_{\mu})$., Comment: 8 pages, 3 figures, v2: matches journal version; v3: includes additional references related to muon g-2 SM prediction

Recent progress on muon $g-2$ measurement prompts one to take it even more seriously. In the general two Higgs doublet model that allows extra Yukawa couplings, we take a simplified approach of single enhanced coupling. We fix the charged lepton flavor violating coupling, $\rho_{\tau\mu} = \rho_{\mu\tau}$, via the one-loop mechanism, for illustrative masses of the heavy scalar $H$ and pseudoscalar $A$, where we assume $m_A = m_{H^+}$. Since extra top Yukawa couplings are plausibly the largest, we turn on $\rho_{tt}$ and find that LHC search for $gg \to H,\,A \to \tau\mu$ gives more stringent bound than from $\tau\to \mu\gamma$ with two-loop mechanism. Turning on a second extra top Yukawa coupling, $\rho_{tc}$, can loosen the bound on $\rho_{tt}$, but LHC constraints can again be more stringent than from $B \to D\mu\nu$ vs $De\nu$ universality. This means that evidence for $H,\,A \to \tau\mu$ may yet emerge with full LHC Run 2 data, while direct search for $\tau^\pm\mu^\mp bW^+$ or $t\bar cbW^+$ (plus conjugate) may also bear fruit., Comment: 7 pages, 5 captioned figures; accepted in PRD

We present a novel approach to the problem of text style transfer. Unlike previous approaches requiring style-labeled training data, our method makes use of readily-available unlabeled text by relying on the implicit connection in style between adjacent sentences, and uses labeled data only at inference time. We adapt T5 (Raffel et al., 2020), a strong pretrained text-to-text model, to extract a style vector from text and use it to condition the decoder to perform style transfer. As our label-free training results in a style vector space encoding many facets of style, we recast transfers as "targeted restyling" vector operations that adjust specific attributes of the input while preserving others. We demonstrate that training on unlabeled Amazon reviews data results in a model that is competitive on sentiment transfer, even compared to models trained fully on labeled data. Furthermore, applying our novel method to a diverse corpus of unlabeled web text results in a single model capable of transferring along multiple dimensions of style (dialect, emotiveness, formality, politeness, sentiment) despite no additional training and using only a handful of exemplars at inference time.

The new round of experiments, MEG II, COMET/Mu2e, and Mu3e, would soon start to push the $\mu \to e\gamma$, $\mu N \to eN$ conversion, and $\mu \to 3e$ frontier, while Belle II would probe $\tau \to \mu\gamma$ and $\tau \to 3\mu$. In the general two Higgs doublet model with extra Yukawa couplings, we show that all these processes probe the lepton flavor violating (LFV) dipole transition that arises from the two loop mechanism, with scalar-induced contact terms subdominant. This is because existing data suggest the extra Yukawa couplings $\rho_{\mu e},\, \rho_{ee} \lesssim \lambda_e$, while $\rho_{\tau\mu},\, \rho_{\tau\tau} \lesssim \lambda_\tau$ and $\rho_{tt} \lesssim \lambda_t$, with $\lambda_i$ the usual Yukawa coupling of the Standard Model (SM), where $\rho_{\mu e}\rho_{tt}$ and $\rho_{\tau\mu}\rho_{tt}$ enter the $\mu e\gamma$ and $\tau\mu\gamma$ two loop amplitudes, respectively. With the $B_s \to \mu\mu$ decay rate basically consistent with SM expectation, together with the $B_s$ mixing constraint, we show that $B_s \to \tau\tau$ would also be consistent with SM, while $B_s \to \tau\mu$ and $B \to K\tau\mu$ decays would be out of reach of projected sensitivities, in strong contrast with some models motivated by the B anomalies., Comment: 11 pages, 3 figures. Added new references and fixed typos to conform to the published version

We explore the interplay between $h(125) \to \tau\mu$ search at the LHC and $\tau \to \mu\gamma$ at the up and coming Belle~II experiment, in context of the general two Higgs doublet model with extra Yukawa couplings such as $\rho_{\tau\mu}$. The search for $h \to \tau\mu$ constrains $\rho_{\tau\mu} \cos\gamma$, where $\cos\gamma$ is the $h$--$H$ mixing angle of $h$ with the exotic $CP$-even scalar $H$. For $\tau \to \mu\gamma$, we define the "BSM-benchmark" by setting the extra top Yukawa coupling $\rho_{tt} = 1\ (\cong \lambda_t)$ in two-loop diagrams, and $\cos\gamma = 0$ to decouple $h$. We show that this leading effect due to $H$ and $CP$-odd scalar $A$ can be readily probed by Belle~II, even for the conservative value of $\rho_{\tau\mu} = 0.7\lambda_\tau$. We define the subleading "$h$-benchmark" by setting $\rho_{tt} = 0$ in two-loop diagrams, and take the conservative maximal value of $\cos\gamma = 0.2$. We show that it falls beyond Belle~II reach, but can interfere with the BSM-benchmark effect, which in principle probes the phase of $\rho_{tt}$. We further show that the one-loop $H$, $A$ effect, proportional to $\rho_{\tau\mu}\rho_{\tau\tau}$ in amplitude, is beyond the sensitivity of Belle~II to probe, even for $\rho_{\tau\tau}$ as large as $3\lambda_\tau$. With the working assumption that $\rho_{32}^f, \rho_{33}^f = {\cal O}(\lambda_3^f)$ for all charged fermions $f$, we find good discovery potential for both $\tau$ lepton flavor violation searches in the coming decade., Comment: 7 pages, 3 figures