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News Article | March 1, 2017
Site: www.prweb.com

Winners of the annual Contractor Project of the Year competition were announced today by Sika Roofing, the worldwide market leader in thermoplastic roofing and waterproofing membranes. A winner and two finalists were recognized for outstanding workmanship in four categories - Low Slope, Steep Slope, Waterproofing and Sustainability - for projects completed using a Sika thermoplastic membrane for roofing or waterproofing applications. “Congratulations to the winners of the 2016 Contractor Project of the Year competition,” said Brian J. Whelan, Sika Roofing’s Executive Vice President. “Each entry is judged on project complexity, design uniqueness, craftsmanship, and creative problem solving. We salute the winners for their dedication to the roofing industry and installation excellence.” RSS Roofing Services & Solutions of St. Louis won first place for installing a Sarnafil RhinoBond System at the Department of Energy’s Gaseous Diffusion Plant in Paducah, Ky. This massive project consisted of 3.2 million square feet of roof area on five separate buildings. The second place winner was Utah Tile & Roofing, Inc., of Salt Lake City for the Peace Coliseum at Overstock’s Corporate Campus, also in Salt Lake City. Third place went to Advanced Roofing Inc., of Fort Lauderdale, Fla., for the National Hurricane Center in Miami. Alliance Roofing Company, Inc., of Santa Clara, Calif., was awarded first place for their work on the beautiful new Endeavor Building at NVIDIA’s Headquarters in Santa Clara. The structure’s distinctive design is based on the triangle, the fundamental building block of computer graphics, and nowhere is that more evident than the complex roof. Midland Engineering Company, Inc., of South Bend, Ind., was the second-place finisher for the Bankers Life Fieldhouse in Indianapolis. Josall Syracuse, Inc., of Syracuse, N.Y., was the third-place finalist for their work on the Onondaga County Water Treatment Plant in Oswego, N.Y. Recover Green Roofs of Somerville, Mass., took first place in the Waterproofing class for their superb work on Harvard Business School’s McArthur Hall/McCollum Center in Boston. The company utilized the Sarnafil G 410 membrane to help create a green roof that has the capability of growing a huge variety of wildflowers and native species that mimic the biology of a natural meadow, self-regenerating with each season. The second-place project was awarded to Nations Roof of Carolina for their impressive green roof on Central Piedmont Community College’s Pease Auditorium, which overlooks the skyline of Charlotte. HRGM Corporation took third place thanks to their work on the Lafayette Elementary School in Washington, D.C. In the Sustainability Category, Sullivan Roofing, Inc., of Schaumburg, Ill., won for the Zurich Insurance North America Headquarters in Schaumburg. This enormous project forced Sullivan Roofing to have three to four crews installing different roofing systems at locations throughout the facility. In second place was Noorda BEC of Salt Lake City for delivering a solar roof with a Sarnafil membrane to the Vivint SmartHome Arena, also in Salt Lake City. In third place for this grouping was BEST Contracting Services, Inc., of Gardena, Calif., for their work on the Los Angeles Convention Center. More than 45 contractors from around the U.S. submitted projects for evaluation in the annual Sika Roofing Project of the Year competition. First place winners were awarded cash prizes, recognition at an awards dinner at the International Roofing Expo and marketing support in the form or advertisements, social media and public relations. Sika is a specialty chemicals company with a leading position in the development and production of systems and products for bonding, sealing, damping, reinforcing and protecting in the building sector and automotive industry. Sika has subsidiaries in 97 countries around the world and manufactures in over 190 factories. Its more than 17,000 employees generated annual sales of CHF 5.75 billion in 2016. For more information about Sika Corporation in the U.S. including Canton, Mass., visit http://usa.sarnafil.sika.com.


Supersolids are defined as systems that spontaneously break two continuous U(1) symmetries: the global phase of the superfluid breaks the internal gauge symmetry, and a density modulation breaks the translational symmetry of space. Starting from superfluid Bose–Einstein condensates (BECs), several forms of supersolidity have been predicted to occur when the condensates feature dipolar interactions13, Rydberg interactions14, superradiant Rayleigh scattering15, nearest-neighbour interaction in lattices16 or spin–orbit interactions5, 6, 7. Work simultaneous with ours used light scattering into two cavities to realize a BEC with supersolid properties17. For fermions, the predicted Fulde–Ferrell–Larkin–Ovchinnikov states have supersolid properties18, 19. Several of these proposals lead to solidity along a single spatial direction maintaining gaseous or liquid-like properties along the other directions. These systems are different from quantum crystals, but share the symmetry-breaking properties. Spin–orbit coupling occurs in solid-state materials when an electron moving at velocity v through an electric field E experiences a Zeeman energy term −μ σ·(v × E) owing to the relativistic transformation of electromagnetic fields. Here σ is the spin vector and μ is the Bohr magneton. The Zeeman term can be written as α v σ /4, where the strength of the coupling α has the units of momentum. The v σ term, together with the transverse magnetic Zeeman term βσ , leads to the Hamiltonian H = ((P  + ασ )2 + P 2 + P 2)/2m + βσ , where m is the atomic mass. A unitary transformation can shift the momenta by ασ , resulting in The second term represents a spin-flip process with a momentum transfer of 2α, which is therefore equivalent to a form of spin–orbit coupling. Such a spin-flip process can be directly implemented for ultracold atoms using a two-photon Raman transition between the two spin states10, 20. Without spin–orbit coupling, a BEC populating two spin states shows no spatial interference, owing to the orthogonality of the states. With spin–orbit coupling, each spin component has now two momentum components (0 and either +2α or −2α, where the sign depends on the initial spin state), which form a stationary spatial interference pattern with a wavevector of 2α (Fig. 1a). Such spatial periodicity of the atomic density can be directly probed with Bragg scattering21, as shown in Fig. 1b. The position of the stripes is determined by the relative phase of the two condensates. This spontaneous phase breaks continuous translational symmetry. The two broken U(1) symmetries are reflected in two long-wavelength collective excitations (the Goldstone modes), one for density (or charge), the other one for spin transport9. Adding a longitudinal Zeeman term δ σ to equation (1) leads to a rich phase diagram6, 22 as a function of δ and β. For sufficiently large , the ground state is in a plane-wave phase. This phase has a roton gap9, 11, which decreases when is reduced, causing a roton instability and leading to a phase transition into the stripe phase. Most experimental studies of spin–orbit coupling with ultracold atoms used two hyperfine ground states coupled by a two-photon Raman spin-flip process10, 11, 12, 23, 24, 25, 26. So far direct evidence of the spatial modulation pattern has been missing, possibly suppressed by stray magnetic fields detuning the Raman transitions and low miscibility between the hyperfine states used (see Methods). Both limitations were recently addressed by a new spin–orbit coupling scheme in which orbital states (the lowest two eigenstates in an asymmetric double-well potential) are used as the pseudospins27. Since the eigenstates mainly populate different wells, their interaction strength g is small and can be adjusted by adjusting their spatial overlap, improving the miscibility (see Methods). Furthermore, since both pseudospin states have the same hyperfine state, there is no sensitivity to magnetic fields. The scheme is realized with a coherently coupled array of double wells using an optical superlattice, a periodic structure with two lattice sites per unit cell with intersite tunnelling J (Fig. 2a). The superlattice has two low-lying bands, split by the energy difference Δ between the double wells, each hosting a BEC in the respective band minima. The BECs in the lower and upper band minima are the pseudospin states in our system. Spin–orbit coupling and the supersolid stripes are created for the free-space motion in the two-dimensional plane orthogonal to the superlattice. The physics in a single two-dimensional plane is not modified in a stack of coherently coupled double wells. However, this increases the signal-to-noise ratio and suppresses the background to the Bragg signal (see below). Experiments started with approximately 1 × 105 23Na atoms forming a BEC loaded into the optical superlattice along the z direction, equally split between the two pseudospin states with a density n ≈ 1.5 × 1014 cm−3. The superlattice consists of laser beams at wavelengths of 1,064 nm and 532 nm, resulting in a lattice constant of d = 532 nm. Spin–orbit coupling was induced by two infrared (IR) Raman laser beams λ  = 1,064 nm along the x and z axes, providing a momentum transfer ħk  = ħ(k , 0, k ) and spin flip from one well to the other with two-photon Rabi frequency Ω. Here ħk  = 2πħ/λ is the recoil momentum from a single infrared photon (see ref. 27 and Methods). The scheme realizes the spin–orbit Hamiltonian in equation (1) with α = k /2, β =  , and an extra Zeeman term δ σ  = (δ − Δ)/2σ , depending on the Raman-beam detuning δ and the superlattice offset Δ. The parameters J, Ω and Δ are determined from calibration experiments27. A separate laser beam was added in the x–y plane to enable detection of the stripes, which form perpendicularly to the superlattice with a periodicity of approximately 2d = 1,064 nm. Their detection requires near-resonant yellow light (Bragg probe light wavelength λ  = 589 nm) at an incident angle θ = 16°, fulfilling the Bragg condition λ  = 4dsinθ. Figure 1b shows the angular distribution of the Rayleigh-scattered light induced by the 589-nm laser at δ  = 0 in the Bragg direction (see Methods). The spin–orbit coupling leads to supersolid stripes and causes a specular reflection of the Bragg beam, observed as a sharp feature in the angular distribution of the Rayleigh-scattered light (Fig. 1b). The angular width (full-width at half-maximum, FWHM) of the observed peak of 9 ± 1 mrad is consistent with the diffraction limit of λ /D, where D is the FWHM size of the cloud, demonstrating phase coherence of the stripes throughout the whole cloud. This observation of the Bragg-reflected beam is our main result, and constitutes a direct observation of the stripe phase with long-range order. For the same parameters, we observe sharp momentum peaks in time of flight27—the signature of BECs—which implies superfluidity. Our detection of the stripe phase is almost background-free, since all other density modulations have different directions, as depicted in Fig. 2a. The superlattice is orthogonal to the stripes, along the axis. The Raman beams form a moving lattice and create a propagating density modulation at an angle of 45° to the superlattice, parallel to . The pseudospin state in the upper band of the superlattice forms at the minimum of the band at a quasimomentum of q = π/d. The wavevector of the stripes is the sum of this quasimomentum and the momentum transfer that accompanies the spin-flip of the spin–orbit coupling interaction27, resulting in a stripe wavevector in the x direction. Since the difference in the wavevectors between the off-resonant density modulation and the stripes is not a reciprocal lattice vector, the Bragg condition cannot be simultaneously fulfilled for both density modulations. This background-free Bragg detection of the stripes uniquely depends on the realization of a coherent array of planar spin–orbit-coupled systems. For a pure condensate, the contrast of the density modulation is predicted5, 6 to be η = 2β/E , which is about 8% for β ≈ 300 Hz. Here E  = 7.6 kHz is the 23Na recoil energy for a single 1,064-nm photon. A sinusoidal density modulation of ηN (where N is the number of atoms in the BEC) atoms gives rise to a Bragg signal equivalent to γ(ηN )2/4, where γ is the independently measured Rayleigh scattering signal per atom per solid angle, and the factor ¼ is the Debye–Waller factor for a sinusoidal modulation. In Fig. 2b, we observed the expected behaviour of the Bragg signal to be proportional to N 2 with the appropriate pre-factors. The prediction for the signal assumes that the stripes are long-range-ordered throughout the whole cloud. If there were m domains, the signal would be m times smaller. Therefore, the observed strength of the Bragg signals confirms the long-range coherence already implied by the sharpness of the angular Bragg peak. Another way to quantify the Bragg signal is to define the ratio of the peak Bragg intensity to the Rayleigh intensity as ‘gain’, which is calculated to be N (fβ/E )2, where f = N /N is the condensate fraction. The inset of Fig. 2b shows the normalized gain as a function of condensate fraction squared. The linear fit to the data points is consistent with a y-axis intercept of zero. This shows that the observed gain comes only from the superfluid component of the atomic sample. Figure 2c shows that the Bragg signal increases with larger spin–orbit-coupling strength up to β ≈ 300 Hz, and starts to decrease owing to heating from the Raman driving (see Methods). Figure 3a shows the phase diagram for spin–orbit-coupled BECs for the parameters implemented in this work. The stripe phase is wide, owing to the high miscibility of the two orbital pseudospin states. Our spin–orbit coupling scheme and the one previously used10, 11 with 87Rb are complementary. In 87Rb, the phase-separated and the single-minimum states were easily observed10, 11, whereas our scheme favours the stripe phase. Exploring the phase diagram in the vertical direction requires varying δ with the two Raman beams detuned. For δ  = 0, spin–orbit coupling leads to two degenerate spin states. For sufficiently large values of , the ground state is the lower spin state. The vertical width of the stripe phase in Fig. 3a depends on the miscibility of the two spin components6, 22. However, population relaxation between the two spin states is very slow10. For our parameters, the equal population of the two pseudospin states is constant during the lifetime of the system for all detunings studied (up to ±10 kHz). Therefore, detection of the stripes is possible even for large detuning. We observed peaked Bragg reflection at δ  ≈ ±0.7E , which was characterized previously as spin-flip resonances coupling to and to (Fig. 3b). These peaks show that density modulations are resonantly created in either the or states. In addition, we observed a third peak around δ  = 0, where the stripe pattern is stationary. For finite δ , it moves at a velocity of δ /k . Our observation shows that the stationary stripe pattern is either more stable or has higher contrast compared to a moving stripe. Since the tunnel coupling along the superlattice direction is weak (about 1 kHz) it seems possible that the alignment of moving stripe patterns is more sensitive to perturbations than for stationary stripes and leads to a reduced Debye–Waller factor for moving stripes. The periodicity of the supersolid density modulation can depend on external, single-atom, and two-atom parameters. In the present case, the periodicity is given by the wavelength and geometry of the Raman beams. It is then further modified by the spin gap parameter β and the interatomic interactions5, 6 to become 2d/ , where F = (2E  + n(g + g ))/4. For β ≈ 300 Hz, the correction due to the interactions is only 0.4% and was not detected in our work. In contrast, for the dipolar supersolid13 and a quantum crystal with vacancies1, 2, the periodicity dominantly depends on atomic interactions. So far, we have presented a supersolid that breaks the continuous translational symmetry in the free-space x direction (Fig. 2a). Unrelated to the presence of spin–orbit coupling, our superlattice system also breaks a discrete translational symmetry along the lattice direction by forming a spatial period that is twice that of the external lattice owing to the interference between atoms in the two pseudospin states with quasimomentum difference Δq = π/d (Fig. 4a) (see ref. 27). This fulfils the definition of a lattice supersolid19, 28. This 1,064-nm-period density modulation has a maximum amplitude of (J/Δ) and oscillates at frequency 2Δ temporally with spontaneous initial phase and can be detected with the same geometry of the Bragg beam and camera, but rotated to the y–z plane. Figure 4b shows the observed enhanced light scattering due to Bragg reflection. The enhancement was absent immediately after preparing an equal mixture of the two pseudospin states, both in q = 0, and appeared spontaneously after the upper pseudospin state relaxed to the band minimum at q = π/d. With the Bragg pulse duration shorter than 1/(2Δ), the Bragg signal varied between 0% and 100%, depending on the phase of the oscillation of the density modulation when probed. The increased fluctuation in Fig. 4b shows the random nature of the initial phase, which is consistent with spontaneous symmetry breaking. In conclusion, we have observed the long-predicted supersolid stripe phase of spin–orbit-coupled BECs. This realizes a system that simultaneously has off-diagonal and diagonal long-range order. In the future, it will be interesting to characterize this system’s collective excitations9 and to find ways to extend it to two-dimensional spin–orbit coupling, which leads to a different and rich phase diagram29. Another direction for future research is the study of vortices and the effects of impurities and disorder in different phases of spin–orbit-coupled condensates30.


News Article | December 13, 2016
Site: www.marketwired.com

SAN MATEO, CA--(Marketwired - Dec 13, 2016) - Agari, a leading cybersecurity company, today announced the release of a new book by Agari Chief Scientist Markus Jakobsson and other cybersecurity thought leaders, Understanding Social Engineering Based Scams. The book describes the increased use of social engineering for email scams, and offers tools and techniques to identify these trends, as well as countermeasures to prevent these attacks. Examples of social engineering attacks, which are typically launched via email, include phishing, spear phishing and Business Email Compromise (BEC). Social engineering-based email attacks, which rely on human interaction and fraudulent behavior to trick people into handing over sensitive information or money, are the fastest growing security threat for enterprises today. While traditional attacks leverage technology-based system vulnerabilities, such as software bugs and misconfigurations, social engineering attacks take advantage of human vulnerabilities by using deception to trick victims into performing harmful actions. Understanding Social Engineering Based Scams provides a good starting point for practitioners, decision makers and researchers in the security space, offering guidance on ways to address the growing problem of social engineering-based cyberattacks, with a focus on understanding the metrics of email-based scams. Chapter topics include Scams and Targeting, Identifying Trends, Why People Fall for Scams, and Filtering Technology, as well as real-life case studies. "Understanding Social Engineering Based Scams is a broad work that touches on a foundational set of issues, with solid analytical underpinnings," said Michael Barrett, CEO of Stealth Security and former CISO of PayPal. "It's an extremely compelling read and I highly recommend it." Jakobsson, editor of Understanding Social Engineering Based Scams, is an established researcher and entrepreneur with deep roots in the cybersecurity community. In his career, he held key positions as Principal Scientist at PayPal, Xerox PARC and RSA Security, and co-founded three digital security startups spanning email fraud prevention, user authentication, mobile malware detection and secure user messaging. Other contributors to the book include highly-recognized security researchers and academics from Cornell University and New York University. "We wrote Understanding Social Engineering Based Scams to help raise awareness of social engineering, which provides the 'deceit' component that has powered some of the world's most visible and successful cyberattacks, including the Ukrainian power grid and Ubiquity attacks in 2015, and the Bangladesh Bank and John Podesta / DNC attacks earlier this year," said Jakobsson. "Social engineering is a real problem for individuals, enterprises and governments. With this book, we hope to lay the foundation for deeper understanding of the problem as without this understanding, we won't be able to stop these scams and prevent the subsequent damages." Hardcover and kindle versions of Understanding Social Engineering Based Scams are available on Amazon. To win a free copy of the book, visit the Agari Social Engineering website. About Agari Agari, a leading cybersecurity company, is trusted by leading Fortune 1000 companies to protect their enterprise, partners and customers from advanced email phishing attacks. The Agari Email Trust Platform is the industry's only solution that 'understands' the true sender of emails, leveraging the company's proprietary, global email telemetry network and patent-pending, predictive Agari Trust Analytics to identify and stop phishing attacks. The platform powers Agari Enterprise Protect, which help organizations protect themselves from advanced spear phishing attacks, and Agari Customer Protect, which protects consumers from email attacks that spoof enterprise brands. Agari, a recipient of the JPMorgan Chase Hall of Innovation Award and recognized as a Gartner Cool Vendor in Security, is backed by Alloy Ventures, Battery Ventures, First Round Capital, Greylock Partners, Norwest Venture Partners and Scale Venture Partners. Learn more at http://www.agari.com and follow us on Twitter @AgariInc. Agari, Agari Email Trust Network and the Agari logo are trademarks or registered trademarks of Agari Data. All other marks are the property of their respective companies.


After optically transporting a cold thermal cloud of 87Rb atoms along the x axis31 into the cavity set-up, we optically evaporate to an almost pure BEC with N = 1.05(3) × 105 (here and in the following the value in parentheses denotes one standard deviation) atoms in a dipole trap, which is formed by two orthogonal laser beams at a wavelength of 1,064 nm along the x and y axes. The final trapping frequencies are (ω , ω , ω ) = 2π × (88(1), 76(3), 154(1)) Hz, resulting in Thomas–Fermi radii of (R , R , R ) = (7.9(1), 9.2(1), 4.5(1)) μm. We subsequently expose the atoms to an attractive one-dimensional lattice potential along the y direction by linearly ramping up the transverse pump beam to a lattice depth of 38(1)ħω within 50 ms. The mirror retroreflecting the transverse pump beam is positioned in vacuum at a distance of 8.6 mm from the atomic position. The beam has a 1/e2 radius of (w , w ) = (35(3), 45(3)) μm and is polarized along , parallel to gravity. The wavelength is set to λ  = 785.3 nm, far red-detuned with respect to the atomic D line. We mounted the mirrors forming the Fabry–Perot cavities as close as possible to each other to achieve large vacuum Rabi rates. For two crossing cavities, this required us to specifically machine the substrates before gluing them in place. The two cavities have comparable single-atom vacuum Rabi frequencies of (g , g ) = 2π × (1.95(1), 1.77(1)) MHz and decay rates (κ , κ ) = 2π × (147(4), 800(11)) kHz. The cavity modes intersect at an angle of 60° and have 1/e2 radii of (49(1), 50(1)) μm. We position the atoms vertically in between the two mode axes, so that they are at a distance of 8(2) μm from each mode centre. For each cavity, we individually set the frequency of a longitudinal mode closely detuned with respect to the transverse pump frequency by stabilizing the cavity lengths with a weak stabilization laser beam at 830.4 nm. The resulting additional intracavity lattice potential is incommensurate with the transverse pump wavelength and has a depth of 0.1(1)ħω , which is negligible compared to the self-organization lattice depth in the organized phases of typically (2–4)ħω . Long-term frequency stability between the transverse pump laser and the stabilization laser of around 50 kHz is achieved by locking all of them simultaneously to a passively stable transfer cavity. Single-photon counting modules are used to detect photons leaving the cavities. The lattice depths of the transverse pump and the intracavity lattices are calibrated by performing Raman–Nath diffraction on the cloud. The calibrated intracavity photon number can then be deduced from the vacuum Rabi frequencies of the cavities. We extract overall intracavity photon detection efficiencies of (η , η ) = (9.7(4)%, 2.0(1)%), with relative systematic uncertainties of 8%. The BEC is prepared in the state with respect to the quantization axis along . The birefringences for the two cavities between the H and V eigenmodes are (4.5, 4.8) MHz. Whenever the resonance condition for a two-photon process involving pump and cavities is met, we observe collective Raman transitions between different Zeeman sublevels accompanied by macroscopic occupation of the cavity modes. To suppress such spin-changing scattering processes, all data were taken at a large offset field of B  = 34 G, creating a Zeeman level splitting that is large compared to Δ and the birefringences. We can therefore neglect the presence of the H-polarized eigenmode and solely couple to the V-polarized mode pointing along the z direction. We start with the following many-body Hamiltonian in a frame rotating at the pump laser frequency23: where the index i ∈ {1, 2} labels the two cavities, ħ is the reduced Planck constant, ϕ is the spatial phase of the transverse pump lattice, m is the mass of one Rb atom and (p , p ) its momentum. The integration runs over the area A of the Wigner–Seitz cell with the spatial coordinate r = (x, y). is the two-photon Rabi frequency for cavity i, the potential depths for cavity i and the transverse pump are given by and , respectively. The vacuum Rabi frequencies of the cavities are denoted by g . The standing-wave transverse pump beam at frequency ω with Rabi frequency Ω is red-detuned by Δ  = ω  − ω from the atomic resonance at frequency ω . It is oriented along the y axis with wavevector . The cavities i ∈ {1, 2} at frequencies ω are detuned by Δ  = ω  − ω from the transverse pump frequency and are described by modes and wavevectors . is the atomic field operator that creates (annihilates) a particle at position (x, y). We neglect any cavity decay rate in this part of our formalism as well as the cavity–cavity interference term, which is negligible for the choice of our experimental parameters. The first term of the Hamiltonian describes the energy of the photon fields in the cavities and the kinetic energy of the atoms. The remaining terms take into account the cavity–pump interference terms for the two cavities, the cavity lattices and the pump lattice. The transverse pump lattice beam at wavelength λ  = 2π/k is far red-detuned with respect to atomic resonance, but closely detuned by Δ to the two cavity resonances. Therefore, photons from the transverse pump can be scattered into a cavity mode and back via off-resonant Raman processes. These two-photon processes coherently couple the zero-momentum state of the BEC to the eight momentum states   , which are sketched in Fig. 1c. We neglect scattering processes between the two cavities, and between excited atomic momentum states, because their amplitudes are negligible for our experimental parameters. Because the cavities and the transverse pump are not orthogonal, these eight momentum states group in high- and low-energy states with energies ħω  = 2ħω [1 + cos(60°)] = 3ħω and ħω  = 2ħω [1 − cos(60°)] = ħω . The single-photon recoil frequency is given by ω = ħk2/(2m), with m the atomic mass. As an ansatz for the atomic field operator we choose where represents the BEC zero-momentum mode, and the functions represent the atomic modes with momentum imprinted by one of the scattering processes at high or low energy into one of the two cavities. After carrying out the integration in equation (1) using equation (2), we obtain the effective Hamiltonian where we have introduced the Raman coupling that can be controlled via . The dispersive shift NU /2 is very similar for both cavities and so can be absorbed into Δ . Other optomechanical terms can be discarded for our parameters. Neglecting a difference between the two Raman couplings, as in the Hamiltonian in the main text, leads to only a small correction because the vacuum Rabi frequencies g are similar. Self-organization to a single cavity occurs when the coupling λ crosses the critical coupling  , with  . This crossing is obtained by changing either λ or Δ . The phase boundary between the SO1 and the SO2 phase is identified by the condition , where the coupling to both cavities is symmetric. Including dissipation rates κ for the cavity fields changes the critical couplings into . The Hamiltonian can be read as the sum of two formally identical Hamiltonians for the two cavities, . Both individually manifest parity symmetry, generated by the operator  . They stay unchanged upon the simultaneous transformation on the photonic and atomic field operators32. This symmetry is broken at the phase transition. The choice of sign of the field operators now corresponds to a choice of 0 or π for the phase of the light field in cavity i, which is equivalent to atoms crystallizing on odd or even sites of a chequerboard lattice with rhomboid geometry. For λ  = λ and Δ  = Δ , the Hamiltonian exhibits a U(1) symmetry instead: it is possible to perform a simultaneous rotation by an arbitrary angle θ in the space of the cavity field and atomic field operators that leaves the Hamiltonian unchanged. The transformation acts in the following way on the operators: It shifts photons between the two cavities while simultaneously redistributing the momentum excitations accordingly. This produces the circle on the α –α plot in Fig. 4c. The corresponding generator of the symmetry is the Hermitian operator It satisfies and, as a direct consequence, the Hamiltonian stays unchanged for any θ under the symmetry ; that is, . This symmetry is spontaneously broken at the phase transition. We can obtain the ground state of the effective Hamiltonian by performing a mean-field expansion around the expectation value of each operator and numerically solving the resulting mean-field Hamiltonian33. To get a direct comparison with the experimentally measured data, we plot the order parameters α and α as a function of the two detunings Δ (see Extended Data Fig. 1). The calculation includes cavity decay, the influence of the transverse pump potential and atom–atom contact interactions. The self-consistent potential in the supersolid phase is formed from the interference between the transverse pump field and the two cavity fields. Here we derive the relation between the spatial position of the optical lattice structure and the ratio between the coherent fields α and α in each cavity. The full potential landscape for the atoms is given by the coherent superposition of the transverse pump field and the two cavity fields, where are the potential depths created by each field. We set ϕ  = ϕ  = 0 by choosing the origin of the coordinate system appropriately. The atomic spatial distribution is then determined by the phase ϕ  ≡ ϕ of the transverse pump standing wave, which we can change via a piezo-electric actuator attached to the retroreflecting transverse pump mirror. For our experimental parameters, such that the atoms are separated into two-dimensional layers in the x–z plane at ky + ϕ = πn, , where k = 2π/λ . Tuning the spatial phase ϕ of the transverse pump standing wave results in triangular (ϕ = 0) and hexagonal (ϕ = π/2) lattice geometries (Extended Data Fig. 2). Within one layer we get where Ω  = Ω cosθ and Ω  = Ω sinθ, with θ corresponding to the position on the α –α circle as before. This describes a lattice whose position depends on θ, unless ϕ = 0, in which case only the lattice depth is modified. The lattice depth has a θ modulation that disappears as ϕ approaches π/2, in which case equation (3) simplifies to . We choose ϕ ≈ π/2 in our experiments such that in the broken U(1) symmetry each realization of cavity fields corresponds to a different translation, as shown in Extended Data Fig. 3. Neighbouring layers move in opposite directions so that the translation is staggered. Although the supersolid phase theoretically extends over only a line in the phase diagram, we experimentally observe a finite width of around 100 kHz. We attribute this to two reasons. First, our experimental preparation of a point in the phase diagram has a finite resolution owing to the stability of the transverse pump frequency and the cavity resonance frequency of around 30–50 kHz each. Second, the chemical potential of the cloud limits the resolution with which we can probe the ground state of the system. Close to the U(1)-symmetric line, the two minima of the parity symmetry are only very weakly pronounced. As the chemical potential increases compared to the depth of the minima, the ground-state manifold approaches a U(1) symmetry. To quantify the homogeneity of the U(1) symmetry we analyse the distribution of the obtained angles. Extended Data Fig. 4 shows the histogram of the observed angles in the positive quadrant of the U(1) manifold for three different points across the supersolid phase. Despite the limited sample sizes, a qualitative difference between the histograms is visible. Whereas the data taken in the centre of the supersolid phase show an almost homogeneous distribution, a clear trend towards the effectively more strongly coupled cavity is visible for a positive or negative change in the detuning Δ . All data files are available from the corresponding author on request.


News Article | March 2, 2017
Site: www.marketwired.com

SAN MATEO, CA--(Marketwired - Mar 2, 2017) - Agari, a leading cybersecurity company, today announced that Info Security Products Guide has named Agari Enterprise Protect a winner of a 2017 Global Excellence Award for Best Security Software. Agari Enterprise Protect is the industry's only email security solution that stops sophisticated social engineering-based email attacks including spear phishing, ransomware and Business Email Compromise (BEC). Email continues to be the primary way cyber criminals infiltrate enterprises. As much as 95% of cyberattacks and data breaches use targeted email attacks as the initial entry point, with attackers evading detection by crafting socially engineered email attacks with no malicious code or URLs. Instead, they impersonate trusted senders such as internal employees, partners or vendors. Agari Enterprise Protect is the only solution that verifies trusted email identities based on insight into 10 billion emails per day to stop these targeted email attacks and protect organizations from email-based data breaches, financial theft, malware delivery, credential theft and critical system compromise. "Info Security Products Guide's recognition of Agari Enterprise Protect highlights the magnitude of the growing problem of advanced email-based attacks that circumvent existing defenses, such as secure email gateways," said Seth Knox, vice president of Marketing for Agari. "Agari Enterprise Protect is the only solution available today that actively prevents these types of attacks that use identity deception to trick people into giving away confidential information that puts employees, partners and brands at risk." About Info Security Products Guide Info Security Products Guide plays a vital role in keeping end-users informed of the choices they can make when it comes to protecting their digital resources. It is written expressly for those who are adamant on staying informed of security threats and the preventive measure they can take. You will discover a wealth of information in this guide including tomorrow's technology today, best deployment scenarios, people and technologies shaping info security and market research reports that facilitate in making the most pertinent security decisions. The Info Security Products Guide Global Excellence Awards recognize and honor excellence in all areas of information security. To learn more, visit www.infosecurityproductsguide.com and stay secured. About Agari Agari, a leading cybersecurity company, is trusted by leading Fortune 1000 companies to protect their enterprise, partners and customers from advanced email phishing attacks. The Agari Email Trust Platform is the industry's only solution that 'understands' the true sender of emails, leveraging the company's proprietary, global email telemetry network and patent-pending, predictive Agari Trust Analytics to identify and stop phishing attacks. The platform powers Agari Enterprise Protect, which help organizations protect themselves from advanced spear phishing attacks, and Agari Customer Protect, which protects consumers from email attacks that spoof enterprise brands. Agari, a recipient of the JPMorgan Chase Hall of Innovation Award and recognized as a Gartner Cool Vendor in Security, is backed by Alloy Ventures, Battery Ventures, First Round Capital, Greylock Partners, Norwest Venture Partners and Scale Venture Partners. Learn more at http://www.agari.com and follow us on Twitter @AgariInc. Agari, Agari Email Trust Network and the Agari logo are trademarks or registered trademarks of Agari Data. All other marks are the property of their respective companies.


News Article | February 15, 2017
Site: physicsworld.com

Taken from the February 2017 issue of Physics World Following a false alarm in 2004, two groups report what could be the first observation of supersolids, a theoretically predicted state of matter that is both a superfluid and a solid at the same time. Stephen Ornes reports We learn it from a young age: solids hold their shapes; liquids flow. Physical states of matter are mutually exclusive. A solid occupies a particular position in space, its molecules fixed. A fluid assumes the shape of its container, its molecules in constant motion. But a so-called supersolid, a predicted phase of matter that forms only under extreme circumstances, doesn’t follow this idea of order. To describe supersolids is an exercise in contradictions. On the one hand, they form rigid crystalline structures. On the other, theory predicts that part of their mass also acts like a superfluid – a quantum phase of matter that flows like a liquid, but without viscosity. That combination lets supersolids do things that seem unfathomable to the humdrum, room-temperature, Newtonian world, like flow through themselves – without friction. Although the Russian physicists Alexander Andreev and Ilya Liftshitz first predicted in 1969 that supersolids could form in helium close to absolute zero, definite proof has been hard to come by, and this elusive phase of matter has largely remained entrenched in the world of theory. That may have changed, though: two independent groups of researchers – one at the Massachusetts Institute of Technology (MIT) in the US, and the other at ETH Zurich in Switzerland – recently reported forming supersolids. Both of the new papers were posted on the arXiv preprint server in October (arXiv:1610.08194; arXiv:1609.09053), though they have not yet been published in peer-reviewed journals. Experts in the field say that so far, the evidence for supersolids looks convincing, with the usual caveats: namely, that more work and replication are needed. Both teams report coaxing supersolids into existence by manipulating a Bose–Einstein condensate (BEC), a bizarre state of matter that forms when bosons are chilled to within a fraction of a degree above absolute zero. The near-simultaneous reporting of two cases of supersolids, found using different experimental approaches, is exciting not only because supersolids may now join the ranks of exotic, fundamental phases, like superconductivity and superfluidity, but also because the material has travelled a long and at times rocky path from prediction to experimental evidence. “There are no scoops in science, only a slow construction of truth,” says physicist Sébastien Balibar at the École Normale Supérieure in Paris, who has conducted research on quantum solids and was not involved in the new studies. “Discoveries are very rarely made in one shot.” The latest reports weren’t the first from physicists who suspected they’d formed supersolids. In a study published in 2004, Pennsylvania State University physicist Moses Chan, together with his graduate student Eun-Seong Kim, reported extraordinary results from experiments using helium-4, the most abundant isotope of helium on Earth (Nature 427 225). At cold temperatures, helium-4 can be encouraged to form either a solid (at high pressure) or a superfluid (at standard pressure). Experiments in the 1930s showed that helium undergoes a phase transition to become a superfluid at 2.2 K, below which it exhibits spectacularly bizarre behaviour, like flowing up the walls of its container and out down the sides. Chan and Kim started with solid helium-4. They put the material in a torsional oscillator – a device that rotates in alternating directions – and lowered the temperature. At a sliver of a degree above absolute zero, the rotation of the device increased in frequency, which suggested that the amount of mass that was rotating had decreased. That change was consistent with the 1969 predictions by Andreev and Liftshitz, who hypothesized that some of the helium’s mass would form a superfluid that could flow through the rest of the solid without friction. Other groups reproduced the experiment and found the same results, exciting the condensed-matter physics community. Still, doubt lingered, and for years, the results from Chan and Kim remained controversial. One team that set out to reproduce the experiment comprised John Reppy, a physicist at Cornell University in the US, and graduate student Sophie Rittner. In a paper published in 2006, they reported that the frequency uptick was tied to defects in the solid helium. When they warmed the helium and let it cool slowly – a process called annealing that smooths out defects – the signature of supersolidity vanished. Then, in a paper published in Nature in 2007, physicist John Beamish at the University of Alberta, Canada, and his collaborators challenged Chan and Kim’s findings by suggesting that solid helium wasn’t perfectly stiff but instead had some give, a “giant plasticity”. This effect could allow some atoms to slide past each other, mimicking the properties of supersolidity. In later experiments, Beamish’s group worked with Balibar and his colleagues in Paris to better understand this effect, and bolstered the case for the new explanation. Chan, ultimately, brought this chapter to its close. Reppy had been Chan’s adviser in graduate school, and Chan set out to redesign his own experiment to test alternative ideas about the supersolid state. In a paper published in 2012 and based on a new set-up, he reported finding no increase in rotational frequency – and thus no evidence for supersolids (Phys. Rev. Lett. 109 155301). “This is a remarkable piece of science history,” says physicist Tilman Pfau, who studies particle interactions in BECs at the University of Stuttgart, in Germany. “The same author that claims something, gets criticized, goes back to the lab, sees he was wrong and writes a paper about it.” While some researchers continue to pursue the formation of supersolids in helium, many other labs have turned to BECs. Albert Einstein first predicted the existence of this state of matter in 1924, based on theoretical work by Indian physicist Satyendra Bose, but it took decades to develop the machinery needed to test the prediction. The first BEC was created in a lab in Colorado, US, in 1995, when physicists used lasers and magnetic fields to trap a clutch of rubidium atoms as the temperature was reduced as much as possible. Just above absolute zero, the individual atoms all began behaving like one giant superatom – a single quantum entity at its lowest energy state. Research into the discovery and properties of BECs netted Nobel prizes for physicists Eric Cornell, at the US National Institute of Standards and Technology, and Carl Wieman, then at the University of Colorado Boulder and now at Stanford University, as well as Wolfgang Ketterle at MIT, whose lab is one of the two that has produced new findings on supersolids. In the two decades since a BEC was first observed, physicists have become adept at finding ways to control every term in the Hamiltonian – the mathematical description of the energy state of the material. It is through tweaking the values of these terms that they’ve been able to probe new fundamental phases of matter, like supersolids. Physicists often characterize transitions between phases of matter by what kind of symmetry is broken. Liquid water, for example, at the molecular level, looks the same under any transformation. The arrangement of molecules at one place in the liquid looks like the arrangement of molecules at another. But ice is a crystal, which means its structure looks the same only when observed at periodic intervals. So the translational symmetry of the liquid is broken as it becomes a crystal. Both forming a crystal and forming a superfluid are associated with breaking symmetry; thus, to form a supersolid requires two kinds of symmetry to break simultaneously. First, a superfluid must be formed. An advantage of working with BECs is that it is well known how to make BECs behave like superfluids, making them a natural place to start; another is that physicists know how to vary atom interactions in the material. Second, while this superfluidity is maintained, the superfluid must become regularly ordered into regions of high and low density, like atoms in a crystal. Physicists have posited a variety of ways to stimulate atom interactions that lead to a solid state while maintaining superfluidity, i.e. the long-sought supersolid state. “Supersolidity is a paradoxical competition between two different and contradictory types of order,” says Balibar. One of those is the order demanded by solidity, where individual atoms line up on a lattice; the other is superfluidity, where the atoms effectively combine, accumulating to the same quantum state. “Atoms in a supersolid should be localized and delocalized at the same time, distinguishable and indistinguishable.” There may be more than one way to coax a solid from a BEC superfluid. One group that reported its findings in October, led by Tilman Esslinger at ETH Zurich, trapped the BEC at the intersection of crossing lasers, with each laser forming an optical cavity. The interaction of the photons and atoms in the BEC gave rise to self-organization – the hallmark of solidity – even though the material continued to look like a superfluid. Pfau says the new work “goes clearly beyond” what groups have done before; Balibar, in Paris, says that the results look “convincing” and “the fundamental effect is clearly there”. At the same time, Balibar cautions that although Esslinger’s group claims evidence for spontaneous symmetry breaking, he’d like to see better confirmation. “That’s not totally obvious to me since the period of the supersolid is fixed by the laser wavelength.” The other group, from Ketterle’s lab at MIT, also used lasers, but with a kind of BEC that takes advantage of the connections between the spin of an atom – an intrinsic quantum property that’s analogous to rotation – and its motion. (Spin–orbit coupling is a physical interaction that underlies many unusual physical phenomena, including topological insulators and some behaviours in superconductors.) The physicists used a laser to transfer some momentum to the atoms in the BEC, which led to the formation of interference patterns. From those patterns emerged tiger-like stripes of alternating density – standing waves – in the material. In its paper, Ketterle’s group reports that this density modulation breaks translational symmetry, the requirement for a solid. Physicist Thomas Busch, who studies quantum processes in ultracold atomic gases at the Okinawa Institute of Science and Technology, in Japan, says theorists predicted a few years ago that the supersolid stripes should emerge. At the same time, he notes that experimental verification is exciting news to the community. Neither group explicitly showed that the material could flow through itself, though the papers do offer arguments in favour of superfluidity. Despite past controversies over what is or isn’t a supersolid, Busch says that the vast majority of people will not have a problem calling the entities in the two new studies supersolids. “Figuring out the exact ‘super’ properties of the states created is now an exciting task for the future,” he says. Finding new states of matter has been a driving force in cold-atom research for decades, and supersolids are the latest bizarre material to join a growing list that already includes things like superfluids and superconductors. For the last two years, Pfau’s group, in Stuttgart, has been exploring quantum ferro­fluids – magnetic droplets that can self-organize out of BECs at low temperature. “Nobody would have thought before [we observed the material in the lab] that this was a stable state of matter,” he says. Last year, in a paper published in Nature, the group reported that quantum ferrofluids can also break translational symmetry, which means they might be a good place to search for other supersolids. Because scientists have been working with BECs for decades, they’ve figured out a lot about how to tame them and tune them to probe fundamental phases of matter. But they’re just getting started, says Busch. Now they’re looking for ways not only to identify other exotic phases, but also to explore what happens when these strange materials are combined, or how they act under other experimental conditions. “How do these systems actually behave by themselves? How do they react to external stimulation? What happens if we squeeze them?” Busch likens this era of discovery to what happened in the years after BECs were first discovered, when physicists couldn’t wait to get to know the new condensates better. “The first thing people did [to BECs] was to squeeze them – the stuff you do when you get a new toy.” In addition, he says, physicists want to study the effects of different long-range interactions and better understand how impurities affect the properties of the materials. Impurities could be critical in finding applications for supersolids. Busch notes that in semiconductor research, impurities added through doping can change the conductivity of a material and make it fit a certain use. Higher dimensions may also be in store. In the preprint from Ketterle’s group, the researchers note a couple of possible future directions: more characterization of the system, for example, or extending their method to a 2D spin–orbit coupling system. Achieving supersolidity in three dimensions would be another major milestone, but breaking symmetries in three dimensions would be difficult to realize in experiments. Exotic states of matter, like supersolids, show that under extreme conditions our physical reality behaves in bizarre ways that aren’t easy to explain. “The physics of cold atoms is some kind of simulation of fundamental problems that are well defined, but hard to calculate,” says Balibar. Theory may predict a spectrum of undiscovered properties that emerge in idealized matter, but controlling such strange stuff under extreme conditions is difficult. “Real matter has defects and surface states,” he says, “so our understanding of real matter is far from being complete.”


By using lasers to manipulate a superfluid gas known as a Bose-Einstein condensate, the team was able to coax the condensate into a quantum phase of matter that has a rigid structure—like a solid—and can flow without viscosity—a key characteristic of a superfluid. Studies into this apparently contradictory phase of matter could yield deeper insights into superfluids and superconductors, which are important for improvements in technologies such as superconducting magnets and sensors, as well as efficient energy transport. The researchers report their results this week in the journal Nature. "It is counterintuitive to have a material which combines superfluidity and solidity," says team leader Wolfgang Ketterle, the John D. MacArthur Professor of Physics at MIT. "If your coffee was superfluid and you stirred it, it would continue to spin around forever." Physicists had predicted the possibility of supersolids but had not observed them in the lab. They theorized that solid helium could become superfluid if helium atoms could move around in a solid crystal of helium, effectively becoming a supersolid. However, the experimental proof remained elusive. The team used a combination of laser cooling and evaporative cooling methods, originally co-developed by Ketterle, to cool atoms of sodium to nanokelvin temperatures. Atoms of sodium are known as bosons, for their even number of nucleons and electrons. When cooled to near absolute zero, bosons form a superfluid state of dilute gas, called a Bose-Einstein condensate, or BEC. Ketterle co-discovered BECs—a discovery for which he was recognized with the 2001 Nobel Prize in physics. "The challenge was now to add something to the BEC to make sure it developed a shape or form beyond the shape of the 'atom trap,' which is the defining characteristic of a solid," explains Ketterle. To create the supersolid state, the team manipulated the motion of the atoms of the BEC using laser beams, introducing "spin-orbit coupling." In their ultrahigh-vacuum chamber, the team used an initial set of lasers to convert half of the condensate's atoms to a different quantum state, or spin, essentially creating a mixture of two Bose-Einstein condensates. Additional laser beams then transferred atoms between the two condensates, called a "spin flip." "These extra lasers gave the 'spin-flipped' atoms an extra kick to realize the spin-orbit coupling," Ketterle says. Physicists had predicted that a spin-orbit coupled Bose-Einstein condensate would be a supersolid due to a spontaneous "density modulation." Like a crystalline solid, the density of a supersolid is no longer constant and instead has a ripple or wave-like pattern called the "stripe phase." "The hardest part was to observe this density modulation," says Junru Li, an MIT graduate student who worked on the discovery. This observation was accomplished with another laser, the beam of which was diffracted by the density modulation. "The recipe for the supersolid is really simple," Li adds, "but it was a big challenge to precisely align all the laser beams and to get everything stable to observe the stripe phase." Mapping out what is possible in nature Currently, the supersolid only exists at extremely low temperatures under ultrahigh-vacuum conditions. Going forward, the team plans to carry out further experiments on supersolids and spin-orbit coupling, characterizing and understanding the properties of the new form of matter they created. "With our cold atoms, we are mapping out what is possible in nature," explains Ketterle. "Now that we have experimentally proven that the theories predicting supersolids are correct, we hope to inspire further research, possibly with unanticipated results." Several research groups were working on realizing the first supersolid. In the same issue of Nature, a group in Switzerland reported an alternative way of turning a Bose-Einstein condensate into a supersolid with the help of mirrors, which collected laser light scattering by the atoms. "The simultaneous realization by two groups shows how big the interest is in this new form of matter," says Ketterle. More information: Jun-Ru Li et al. A stripe phase with supersolid properties in spin–orbit-coupled Bose–Einstein condensates, Nature (2017). DOI: 10.1038/nature21431


News Article | February 28, 2017
Site: www.businesswire.com

DALLAS--(BUSINESS WIRE)--Trend Micro Incorporated (TYO: 4704; TSE: 4704), a global leader in cybersecurity solutions, today released its annual security roundup report, “2016 Security Roundup: A Record Year for Enterprise Threats,” which proves 2016 was truly the year of online extortion. Cyber threats reached an all-time high in 2016, with ransomware and Business Email Compromise (BEC) scams gaining increased popularity among cybercriminals looking to extort enterprises. A 752 percent increase in new ransomware families ultimately resulted in $1 billion in losses for enterprises worldwide. Trend Micro and the Zero Day Initiative (ZDI) discovered 765 vulnerabilities in 2016. Of these, 678 were brought to ZDI through their bug bounty program, then ZDI verifies and discloses the issue to the affected vendor. Compared to vulnerabilities discovered by Trend Micro and ZDI in 2015, Apple saw a 145 percent increase in vulnerabilities, while Microsoft bugs decreased by 47 percent. Additionally, the use of new vulnerabilities in exploit kits dropped by 71 percent, which is partially due to the arrest of the threat actors behind Angler that took place in June 2016. “As threats have diversified and grown in sophistication, cybercriminals have moved on from primarily targeting individuals to focusing on where the money is: enterprises,” said Ed Cabrera, chief cybersecurity officer for Trend Micro. “Throughout 2016 we witnessed threat actors extort companies and organizations for the sake of profitability and we don’t anticipate this trend slowing down. This research aims to educate enterprises on the threat tactics actively being used to compromise their data, and help companies adopt strategies to stay one step ahead and protect against potential attacks.” In 2016, the Trend Micro Smart Protection Network™ blocked more than 81 billion threats for the entire year, which is a 56 percent increase from 2015. In the second half of 2016, more than 3,000 attacks per second were blocked for customers. During this time, 75 billion of blocked attempts were email based, illustrating that email remains the top entry point for threats. For the complete report, please visit: https://www.trendmicro.com/vinfo/us/security/research-and-analysis/threat-reports/roundup/2016-roundup-record-year-enterprise-threats. Trend Micro Incorporated, a global leader in cybersecurity solutions, helps to make the world safe for exchanging digital information. Our innovative solutions for consumers, businesses, and governments provide layered security for data centers, cloud environments, networks, and endpoints. All our products work together to seamlessly share threat intelligence and provide a connected threat defense with centralized visibility and control, enabling better, faster protection. With more than 5,000 employees in over 50 countries and the world’s most advanced global threat intelligence, Trend Micro enables organizations to secure their journey to the cloud. For more information, visit www.trendmicro.com.


News Article | August 22, 2016
Site: www.nature.com

Black holes are not actually black. Instead, these gravitational sinks are thought to emit radiation that causes them to shrink and eventually disappear. This phenomenon, one of the weirdest things about black holes, was predicted by Stephen Hawking more than 40 years ago, creating problems for theoretical physics that still convulse the field. Now, after seven years of often solitary study, Jeff Steinhauer, an experimental physicist at the Technion-Israel Institute of Technology in Haifa, has created an artificial black hole that seems to emit such ‘Hawking radiation’ on its own, from quantum fluctuations that emerge from its experimental set-up. It is nearly impossible to observe Hawking radiation in a real black hole, and previous artificial-black-hole experiments did not trace their radiation to spontaneous fluctuations. So the result, published on 15 August1, could be the closest thing yet to an observation of Hawking radiation. Steinhauer says that black-hole analogues might help to solve some of the dilemmas that the phenomenon poses for other theories, including one called the black-hole information paradox, and perhaps point the way to uniting quantum mechanics with a theory of gravity. Other physicists are impressed, but they caution that the results are not clear-cut. And some doubt whether laboratory analogues can reveal much about real black holes. “This experiment, if all statements hold, is really amazing,” says Silke Weinfurtner, a theoretical and experimental physicist at the University of Nottingham, UK. “It doesn’t prove that Hawking radiation exists around astrophysical black holes.” It was in the mid-1970s that Hawking, a theoretical physicist at the University of Cambridge, UK, discovered that the event horizon of a black hole — the surface from which nothing, including light, can escape — should have peculiar consequences for physics. His starting point was that the randomness of quantum theory ruled out the existence of true nothingness. Even the emptiest region of space teems with fluctuations in energy fields, causing photon pairs to appear continuously, only to immediately destroy each other. But, just as Pinocchio turned from a puppet into a boy, these ‘virtual’ photons could become real particles if the event horizon separated them before they could annihilate each other. One photon would fall inside the event horizon and the other would escape into outer space. This, Hawking showed, causes black holes both to radiate — albeit extremely feebly — and to ultimately shrink and vanish, because the particle that falls inside always has a ‘negative energy’ that depletes the black hole. Most controversially, Hawking also suggested that a black hole’s disappearance destroys all information about objects that have fallen into it, contradicting the accepted wisdom that the total amount of information in the Universe stays constant. In the early 1980s, physicist Bill Unruh of the University of British Columbia in Vancouver, Canada, proposed a way to test some of Hawking’s predictions2. He imagined a medium that experienced accelerated motion, such as water approaching a waterfall. Like a swimmer reaching a point where he cannot swim fast enough away to escape the waterfall, sound waves that are past the point in the medium that surpasses the speed of sound would become unable to move against the flow. Unruh predicted that this point is equivalent to an event horizon — and that it should display a sonic form of Hawking radiation. Steinhauer implemented Unruh’s idea in a cloud of rubidium atoms that he cooled to a fraction of a degree above absolute zero. Contained in a cigar-shaped trap a few millimetres long, the atoms entered a quantum state called a Bose–Einstein condensate (BEC), in which the speed of sound was just half a millimetre per second. Steinhauer created an event horizon by accelerating the atoms until some were travelling at more than 1 mm s−1 — a supersonic speed for the condensate (see ‘Building a black hole’). At its ultracold temperature, the BEC undergoes only weak quantum fluctuations that are similar to those in the vacuum of space. And these should produce packets of sound called phonons, just as the vacuum produces photons, Steinhauer says. The partners should separate from each other, with one partner on the supersonic side of the horizon and the other forming Hawking radiation. On one side of his acoustical event horizon, where the atoms move at supersonic speeds, phonons became trapped. And when Steinhauer took pictures of the BEC, he found correlations between the densities of atoms that were an equal distance from the event horizon but on opposite sides. This demonstrates that pairs of phonons were entangled — a sign that they originated spontaneously from the same quantum fluctuation, he says, and that the BEC was producing Hawking radiation. By contrast, radiation that he observed in an earlier version of the set-up had to be triggered rather than arising from the BEC itself3, whereas a previous experiment in water waves led by Unruh and Weinfurtner did not attempt to show quantum effects4. Just as real black holes are not black, Steinhauer’s acoustical black holes are not completely quiet. Their sound, if it were audible, might resemble static noise. “For sure, this is a pioneering paper,” says Ulf Leonhardt, a physicist at the Weizmann Institute of Science in Rehovot, Israel, who leads a different attempt to demonstrate the effect, using laser waves in an optical fibre. But he says that the evidence of entanglement seems incomplete, because Steinhauer demonstrated correlations only for phonons of relatively high energies, with lower-energy phonon pairs seemingly not correlated. He also says he’s not confident that the medium is a true BEC, which, he says, means that there could be other types of fluctuation that could mimic Hawking radiation. Also unclear is what analogues can say about the mysteries surrounding true black holes. “I don’t believe it will illuminate the so-called information paradox,” says Leonard Susskind, a theoretical physicist at Stanford University in California. In contrast to the case of astrophysical black holes, there is no information loss in Steinhauer’s sonic black hole because the BEC does not evaporate. Still, if Steinhauer’s results were confirmed, it would be “a triumph for Hawking, perhaps in the same sense that the expected detection of the Higgs boson was a triumph for Higgs and company”, says Susskind. Few doubted that the particle existed, but its discovery in 2012 still earned Peter Higgs and another theorist, François Englert, who predicted it, a Nobel prize.


News Article | March 1, 2017
Site: www.marketwired.com

HONG KONG, CHINA--(Marketwired - Mar 1, 2017) - Trend Micro Incorporated (TYO: 4704; TSE: 4704), a global leader in cybersecurity solutions, today released its annual security roundup report, "2016 Security Roundup: A Record Year for Enterprise Threats," which proves 2016 was truly the year of online extortion. Cyber threats reached an all-time high in 2016, with ransomware and Business Email Compromise (BEC) scams gaining increased popularity among cybercriminals looking to extort enterprises. A 752 percent increase in new ransomware families ultimately resulted in $1 billion in losses for enterprises worldwide. Trend Micro and the Zero Day Initiative (ZDI) discovered 765 vulnerabilities in 2016. Of these, 678 were brought to ZDI through their bug bounty program, then ZDI verifies and discloses the issue to the affected vendor. Compared to vulnerabilities discovered by Trend Micro and ZDI in 2015, Apple saw a 145 percent increase in vulnerabilities, while Microsoft bugs decreased by 47 percent. Additionally, the use of new vulnerabilities in exploit kits dropped by 71 percent, which is partially due to the arrest of the threat actors behind Angler that took place in June 2016. "As threats have diversified and grown in sophistication, cybercriminals have moved on from primarily targeting individuals to focusing on where the money is: enterprises," said Tony Lee, Consultant at Trend Micro Hong Kong. "Throughout 2016 we witnessed threat actors extort companies and organizations for the sake of profitability and we don't anticipate this trend slowing down. This research aims to educate enterprises on the threat tactics actively being used to compromise their data, and help companies adopt strategies to stay one step ahead and protect against potential attacks." In 2016, the Trend Micro Smart Protection Network™ blocked more than 81 billion threats for the entire year, which is a 56 percent increase from 2015. In the second half of 2016, more than 3,000 attacks per second were blocked for customers. During this time, 75 billion of blocked attempts were email based, illustrating that email remains the top entry point for threats. For the complete report, please visit: https://www.trendmicro.com.hk/vinfo/hk/security/research-and-analysis/threat-reports/roundup About Trend Micro Trend Micro Incorporated, a global leader in cyber security solutions, helps to make the world safe for exchanging digital information. Our innovative solutions for consumers, businesses, and governments provide layered security for data centers, cloud environments, networks, and endpoints. All our products work together to seamlessly share threat intelligence and provide a connected threat defense with centralized visibility and control, enabling better, faster protection. With more than 5,000 employees in over 50 countries and the world's most advanced global threat intelligence, Trend Micro enables users to enjoy their digital lives safely. For more information, visit www.trendmicro.com.hk.

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