ITP OpenIR
http://ir.itp.ac.cn/:80
中国科学院理论物理研究所Mon, 27 Sep 2021 13:04:43 GMT2021-09-27T13:04:43ZYao.jl: Extensible, Efficient Framework for Quantum Algorithm Design
http://ir.itp.ac.cn/:80/handle/311006/27539
Title: Yao.jl: Extensible, Efficient Framework for Quantum Algorithm Design
Authors: Luo, Xiu-Zhe; Liu, Jin-Guo; Zhang, Pan; Wang, Lei
Description: We introduce Yao, an extensible, efficient open-source framework for quantum algorithm design. Yao features generic and differentiable programming of quantum circuits. It achieves state-of-the-art performance in simulating small to intermediatesized quantum circuits that are relevant to near-term applications. We introduce the design principles and critical techniques behind Yao. These include the quantum block intermediate representation of quantum circuits, a builtin automatic differentiation engine optimized for reversible computing, and batched quantum registers with GPU acceleration. The extensibility and efficiency of Yao help boost innovation in quantum algorithm design.Mon, 27 Sep 2021 08:42:01 GMThttp://ir.itp.ac.cn/:80/handle/311006/275392021-09-27T08:42:01ZWeyl scaling invariant R-2 gravity for inflation and dark matter
http://ir.itp.ac.cn/:80/handle/311006/27537
Title: Weyl scaling invariant R-2 gravity for inflation and dark matter
Authors: Tang, Yong; Wu, Yue-Liang
Description: Inflation in the early universe can generate the nearly conformal invariant fluctuation that leads to the structures we observe at the present. The simple viable Starobinsky R-2 inflation has an approximate global scale symmetry. We study the conformal symmetric Weyl (R) over cap (2) and general F((R) over cap) theories and demonstrate their equivalence to Einstein gravity coupled with a scalar and a Weyl gauge field. The scalar field in Weyl (R) over cap (2) gravity can be responsible for inflation with Starobinsky model as the attractor, potentially distinguishable from the latter by future experiments. The intrinsic Weyl gauge boson becomes massive once the Einstein frame is fixed, and constitutes as a dark matter candidate with mass up to similar to 5 x 10(16) GeV. (c) 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Mon, 27 Sep 2021 08:42:00 GMThttp://ir.itp.ac.cn/:80/handle/311006/275372021-09-27T08:42:00ZWhere Is the Lightest Charmed Scalar Meson?
http://ir.itp.ac.cn/:80/handle/311006/27538
Title: Where Is the Lightest Charmed Scalar Meson?
Authors: Du, Meng-Lin; Guo, Feng-Kun; Hanhart, Christoph; Kubis, Bastian; Meissner, Ulf-G
Description: The lightest charmed scalar meson is known as the D-0*(2300), which is one of the earliest new hadron resonances observed at modern B factories. We show here that the parameters assigned to the lightest scalar D meson are in conflict with the precise LHCb data of the decay B- -> D+pi(-) pi(-) . On the contrary, these data can be well described by an unitarized chiral amplitude containing a much lighter charmed scalar meson, the D-0*(2100). We also extract the low-energy S-wave D pi phase of the decay B- -> D+pi(-) pi(-) - from the data in a model-independent way, and show that its difference from the D pi scattering phase shift can be traced back to an intermediate rho(-) exchange. Our work highlights that an analysis of data consistent with chiral symmetry, unitarity, and analyticity is mandatory in order to extract the properties of the ground-state scalar mesons in the singly heavy sector correctly, in analogy to the light scalar mesons f(0) (500) and K-0*(700).Mon, 27 Sep 2021 08:42:00 GMThttp://ir.itp.ac.cn/:80/handle/311006/275382021-09-27T08:42:00ZWarm-assisted natural inflation
http://ir.itp.ac.cn/:80/handle/311006/27535
Title: Warm-assisted natural inflation
Authors: Reyimuaji, Yakefu; Zhang, Xinyi
Description: We consider natural inflation in a warm inflation framework with a temperature-dependent dissipative coefficient Gamma proportional to T-3. Natural inflation can be compatible with the Planck 2018 results with such warm assistance. With no a priori assumptions on the dissipative effect's magnitude, we find that the Planck results prefer a weak dissipative regime for our benchmark scale f = 5M(pl), which lies outside the 2 sigma region in the cold case. The inflation starts in the cold regime and evolves with a growing thermal fluctuation that dominates over quantum fluctuation before the end of the inflation. The observed spectral tilt puts stringent constraints on the model's parameter space. We find that f <1M(pl) is excluded. A possible origin of such dissipative coefficient from axion-like coupling to gauge fields and tests of the model are also discussed.Mon, 27 Sep 2021 08:41:59 GMThttp://ir.itp.ac.cn/:80/handle/311006/275352021-09-27T08:41:59ZWeak directed transport of inertial Levy flights in rough corrugated potential
http://ir.itp.ac.cn/:80/handle/311006/27536
Title: Weak directed transport of inertial Levy flights in rough corrugated potential
Authors: Liu, Jian; Zhu, Ping; Li, Feifei
Description: The directed transport of inertial Levy flights resulting from the superimposed roughness in a corrugated potential is investigated in this paper. The influence of the roughness on the transport is studied by calculating the mean velocity (MV) and the mean first escape time (MFET), with respect to the Levy index mu and the asymmetry parameter q which determines the asymmetry of the potential. The results indicate that the particles' directed transport caused by the asymmetry of the potential will be counteracted by the roughness, which behaves as the absolute value of the MV decreases with roughness epsilon increasing, and the MFET increases with increasing, correspondingly. Though smaller Levy index mu can produce more large jumps, which yield the enhancement of the directed transport, since the roughness superimposed on the corrugated potential supplies the hinder effect, the directed transport is also weakened after the appearance of the roughness.Mon, 27 Sep 2021 08:41:59 GMThttp://ir.itp.ac.cn/:80/handle/311006/275362021-09-27T08:41:59ZVulnerability and resilience of social engagement: Equilibrium theory
http://ir.itp.ac.cn/:80/handle/311006/27534
Title: Vulnerability and resilience of social engagement: Equilibrium theory
Authors: Wang, Shang-Nan; Cheng, Luan; Zhou, Hai-Jun
Description: Social networks of engagement sometimes dramatically collapse. A widely adopted paradigm to understand this catastrophe dynamics is the threshold model but previous work only considered the irreversible K-core pruning process and the resulting kinetic activity patterns. Here we study the network alliance problem as a simplified model of social engagement by equilibrium statistical mechanics. Our theory reveals that the surviving kinetic alliances are out-of-equilibrium and atypical configurations which may become highly vulnerable to single-node-triggered cascading failures as they relax towards equilibrium. Our theory predicts that if the fraction of active nodes is beyond certain critical value, the equilibrium (typical) alliance configurations could be protected from cascading failures by a simple least-effort local intervention strategy. We confirm these results by extensive Monte Carlo simulations. Copyright (C) 2021 EPLAMon, 27 Sep 2021 08:41:58 GMThttp://ir.itp.ac.cn/:80/handle/311006/275342021-09-27T08:41:58ZVariational Approach for Many-Body Systems at Finite Temperature
http://ir.itp.ac.cn/:80/handle/311006/27533
Title: Variational Approach for Many-Body Systems at Finite Temperature
Authors: Shi, Tao; Demler, Eugene; Cirac, J. Ignacio
Description: We introduce an equation for density matrices that ensures a monotonic decrease of the free energy and reaches a fixed point at the Gibbs thermal. We build a variational approach for many-body systems that can be applied to a broad class of states, including all bosonic and fermionic Gaussian, as well as their generalizations obtained by unitary transformations, such as polaron transformations in electron-phonon systems. We apply it to the Holstein model on 20 x 20 and 50 x 50 square lattices, and predict phase separation between the superconducting and charge-density wave phases in the strong interaction regime.Mon, 27 Sep 2021 08:41:58 GMThttp://ir.itp.ac.cn/:80/handle/311006/275332021-09-27T08:41:58ZUV completed composite Higgs model with heavy composite partners
http://ir.itp.ac.cn/:80/handle/311006/27532
Title: UV completed composite Higgs model with heavy composite partners
Authors: Dong, Zi-Yu; Guan, Cong-Sen; Ma, Teng; Shu, Jing; Xue, Xiao
Description: We study electroweak symmetry breaking in minimal composite Higgs models SU(4)/Sp(4) with purely fermionic UV completions based on a confining hypercolor gauge group and find that the extra Higgs potential from the underlying preon mass can destruct the correlation between the mass of Higgs and composite partners. Thus, the composite partners can be very heavy for successful electroweak symmetry breaking without enhancing the separation between the new physical scale and Higgs vacuum expectation value. So this kind of model can be easily realized by ordinary strong dynamics theories without artificial assumptions and, more likely, consistent with lattice simulations. The UV completion of partial compositeness predicts a light singlet Goldstone boson, which interacts with QCD and electroweak gauge bosons through Wess-Zumino-Witten terms. It can he produced through gluon fusion at LHC and decay into gauge boson pairs. We briefly discuss its phenomenology and derive its bounds from LHC searches.Mon, 27 Sep 2021 08:41:57 GMThttp://ir.itp.ac.cn/:80/handle/311006/275322021-09-27T08:41:57ZUniversal infrared scaling of gravitational wave background spectra
http://ir.itp.ac.cn/:80/handle/311006/27530
Title: Universal infrared scaling of gravitational wave background spectra
Authors: Cai, Rong-Gen; Pi, Shi; Sasaki, Misao
Description: We study the general infrared behavior of the power spectrum of a stochastic gravitational wave background produced by stress tensor in the form bilinear in certain dynamical degrees of freedom. We find Omega(GW) proportional to k(3) for a very wide class of the sources which satisfy a set of reasonable conditions. Namely, the k3 scaling is universally valid when the source term is bounded in both frequency and time, is effective in a radiation-dominated stage, and for k smaller than all the physical scales associated with the source, like the peak frequency, peak width, and time duration, etc. We also discuss possible violations of these conditions and their physical implications.Mon, 27 Sep 2021 08:41:56 GMThttp://ir.itp.ac.cn/:80/handle/311006/275302021-09-27T08:41:56ZUniversal upper bound on the inflationary energy scale from the trans-Planckian censorship conjecture
http://ir.itp.ac.cn/:80/handle/311006/27531
Title: Universal upper bound on the inflationary energy scale from the trans-Planckian censorship conjecture
Authors: Mizuno, Shuntaro; Mukohyama, Shinji; Pi, Shi; Zhang, Yun-Long
Description: We study the constraint on the inflationary energy scale from the recently proposed trans-Planckian censorship conjecture (TCC). We find a universal upper bound on the inflationary Hubble expansion rate H-inf which is solely determined by the reheating temperature T-rh: H-inf/M-pl less than or similar to T-0/T-rh, where T-0 is the photon temperature today. The upper limit can be saturated by a postinflationary oscillatory stage with the critical equation-of-state parameter w approximate to 1/3, or by an inflation model with multiple stages. In the lowest reheating temperature required for big bang nucleosynthesis, the upper bound on the tensor-to-scalar ratio r at the CMB scales is r less than or similar to 10(-8), which can be realized in many string-inspired inflation models.Mon, 27 Sep 2021 08:41:56 GMThttp://ir.itp.ac.cn/:80/handle/311006/275312021-09-27T08:41:56Z