Russia's Responses to Acts of Terrorism

EDITOR'S INTRODUCTION | A week following the terrorist attacks of September 11, 2001, the University of Michigan International Institute assembled a faculty panel to begin a dialogue on terrorism and globalization. The panel was designed with a university of the world in mind, a sanctuary for reason and reflection during a time of anger and grief. Two years prior to the terrorist destruction of the World Trade Center, Russia suffered a series of terrorist attacks against civilians. Panelist Alexander Knysh, professor of Islamic Studies and chairman of the department of Near Eastern studies at the University of Michigan, revisits these events and provides a context for understanding the terrorist attacks. Knysh analyses Russia's response, draws parallels between the US and Russian situations, and cautions that a war in Afghanistan will be extremely difficult to win.http://deepblue.lib.umich.edu/bitstream/2027.42/55291/2/main.csshttp://deepblue.lib.umich.edu/bitstream/2027.42/55291/1/index.htm

Quantum supremacy using a programmable superconducting processor

The promise of quantum computers is that certain computational tasks might be executed exponentially faster on a quantum processor than on a classical processor1. A fundamental challenge is to build a high-fidelity processor capable of running quantum algorithms in an exponentially large computational space. Here we report the use of a processor with programmable superconducting qubits to create quantum states on 53 qubits, corresponding to a computational state-space of dimension 2^53 (about 10^16). Measurements from repeated experiments sample the resulting probability distribution, which we verify using classical simulations. Our Sycamore processor takes about 200 seconds to sample one instance of a quantum circuit a million times—our benchmarks currently indicate that the equivalent task for a state-of-the-art classical supercomputer would take approximately 10,000 years. This dramatic increase in speed compared to all known classical algorithms is an experimental realization of quantum supremacy for this specific computational task, heralding a much-anticipated computing paradigm

Measurement of Hadronic Mass Moments ⟨MXn⟩\langle M_X^n \rangle in B→Xcℓνℓ B \rightarrow X_c \ell \nu_\ell\ Decays at Belle II

We present measurements of the first six hadronic mass moments in semileptonic $B \rightarrow X_c \ell \nu_\ell\$ decays. The hadronic mass moments, together with other observables of inclusive $B$ decays, can be used to determine the CKM matrix element $|{V_{cb}}|$ and mass of the $b$-quark $m_b$ in the context of Heavy Quark Expansions of QCD. The Belle~II data recorded at the $\Upsilon (4S)$ resonance in 2019 and 2020 (March-July), corresponding to an integrated luminosity of $34.6\;\mathrm{fb}^{-1}$, is used for this measurement. The decay $\Upsilon (4S) \rightarrow B \overline{B}$ is reconstructed by applying the hadronic tagging algorithm provided by the Full Event Interpretation to fully reconstruct one $B$ meson. The second $B$ meson is reconstructed inclusively by selecting a high-momentum lepton. The $X_c$ system is identified by the remaining reconstructed tracks and clusters in the electromagnetic calorimeter. We report preliminary results for the hadronic mass moments $\langle M_X^n \rangle$ with $n=1,\dots,6$, measured as a function of a lower cut on the lepton momentum in the signal $B$ rest frame