Dirac Monopoles from Weyl Hamiltonian by Green’s Functions

by Tommy on 4/05/2016


Topological Numbers and the Weyl Semimetal, Mahmut Elbistan (3 May 2016)

Generalized Dirac monopoles in momentum space are constructed in even d+1 dimensions from the Weyl Hamiltonian in terms of Green’s functions. In 3+1 spacetime dimensions, the (unit) charge of the monopole is equal to both the winding number and the Chern number, expressed as the integral of the Berry curvature. Based on the equivalence of the Chern and winding numbers, a chirally coupled field theory action is proposed for the Weyl semimetal phase. At the one loop order, the effective action yields both the chiral magnetic effect and the anomalous Hall effect. The Chern number appears as a coefficient in the conductivity, thus emphasizes the role of topology. The anomalous contribution of chiral fermions to transport phenomena is reflected as the gauge anomaly with the topological term E . B. Relevance of monopoles and Chern numbers for the semiclassical chiral kinetic theory is also discussed.

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Kibble – Zurek Mechanism Simulated in Cold Atom Systems

by Tommy on 4/05/2016


Universal space-time scaling symmetry in the dynamics of bosons across a quantum phase transition, Logan W. Clark, Lei Feng and Cheng Chin (3 May 2016)

The dynamics of many-body systems spanning condensed matter, cosmology, and beyond is hypothesized to be universal when the systems cross continuous phase transitions. The universal dynamics is expected to satisfy a scaling symmetry of space and time with the crossing rate, inspired by the Kibble-Zurek mechanism. We test this symmetry based on Bose condensates in a shaken optical lattice. Shaking the lattice drives condensates across an effectively ferromagnetic quantum phase transition. After crossing the critical point, the condensates manifest delayed growth of spin fluctuations and develop anti-ferromagnetic spatial correlations resulting from sub-Poisson generation of topological defects. The characteristic times and lengths scale as power-laws of the crossing rate, yielding the temporal exponent 0.50(2) and the spatial exponent 0.26(2), consistent with theory. Furthermore, the fluctuations and correlations are invariant in scaled space-time coordinates, in support of the scaling symmetry of quantum critical dynamics.

To Infinity, And Beyond!

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I, Tommy – I’m Naming the SI Unit of Momentum After Myself

by Tommy on 30/04/2016
Higgs Particle Collision

Higgs Particle Collision

Ok, after inventing the scientific domain of engineering science, and then going on to invent the subdomain of ‘quantum astrophysics’, what do I do for an encore? Well, I did this quite a while ago during the era of the static ISP website, simple javascripts and AJAX, on my fundamental physical and chemical units, symbols and constants pages and then in my infamous AJAXified interactive periodic table of the elements. The SI unit of momentum is mine! I’m claiming it. Me.

SI Unit of Momentum

Symbol : I (Impulse)

Name : Fritz

Units : kg m s-1

You heard it here first. I can’t remember if I ever posted this to the usenet.

I dare you to out crackpot this.

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Growth, Transport Properties – Bismuth on Potassium Chloride

by Tommy on 29/04/2016


Semiconductor- to metallic-like behavior in Bi thin films on KCl substrate, Thanh Nhan Bui, Jean-Pierre Raskin and Benoit Hackens, J. Appl. Phys. 119, 135304 (5 April 2016); DOI:10.1063/1.4945036

Bi thin films, with a thickness of 100 nm, are deposited by electron-beam evaporation on a freshly cleaved (100) KCl substrate. The substrate temperature during film growth (Tdep) ranges from room temperature up to 170 °C. Films deposited at room temperature exhibit a maze-like microstructure typical of the rhombohedral (110) texture, as confirmed by X-ray diffraction. For Tdep above 80 °C, a different microstructure appears, characterized by concentric triangular shapes corresponding to the trigonal (111) texture. Temperature dependence of the resistivity shows a transition from a semiconductor-like behavior for films deposited at room temperature to a metallic-like behavior for Tdep above 80 °C. From magnetoresistance measurements between room temperature and 1.6 K, we extract the electron and hole mobilities, concentrations, and mean free paths, which allow to draw a complete picture of the transport properties of both types of films.

Ok, back to the grind.

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CDW Phase Diagram of the Cuprates Further Refined Yet Again

by Tommy on 28/04/2016
Dynamic Fluctuating CDW Cuprate Phase Diagram

Dynamic Fluctuating CDW Cuprate Phase Diagram


Dynamical charge density waves rule the phase diagram of cuprates, S. Caprara, C. Di Castro, G. Seibold and M. Grilli (26 April 2016)

In the last few years charge density waves (CDWs) have been ubiquitously observed in cuprates and are now the most investigated among the competing orders in the longstanding (but still hot) debate on high-temperature superconducting cuprates. Different dome-shaped CDW onset lines in the temperature vs. doping phase diagram are detected by experiments with probes having different characteristic timescales. These lines are extrapolated at zero temperature to different quantum critical points (QCPs) in agreement with the long-standing theoretical result that CDW’s are present in these systems and disappear with a QCP by increasing doping. This QCP is buried underneath the superconducting dome, in the optimal doping region (i.e., where the superconducting critical temperature Tc is highest). A wealth of new experimental data raise fundamental issues that challenge the various theoretical proposals. Here, we reproduce the complex experimental phase diagram and provide a coherent solution to all these problems based on the occurrence of dynamically fluctuating CDWs.

Who did not see this coming?

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Optimum Performance of Thermoelectric Energy Conversion

by Tommy on 28/04/2016


Thermoelectric energy converters under a trade-off figure of merit with broken time-reversal symmetry, I. Iyyappan and M. Ponmurugan (26 April 2016)

We study the optimum performance of the thermoelectric energy converters such as heat engines and refrigerators with broken time-reversal symmetry by applying unified trade-off figure of merit Ω˙, which takes the account of best compromise between the maximum work extraction and the minimum work loss. We find that the maximum Ω˙ criterion provide the significantly high performance of the thermoelectric energy converter if the system possess reasonably large value of the asymmetric parameter as compared to the maximum χ criterion. However, the maximum χ criterion provide the better performance than the maximum Ω˙ criterion for low value of the asymmetric parameter. Our results can be useful to design high efficient real thermoelectric heat engines and refrigerators with broken time-reversal symmetry.

These kinds of in depth analyses are extremely insightful and helpful.

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Quantum Proton Tunneling of Water Molecules Trapped in Beryl

by Tommy on 26/04/2016


Quantum Tunneling of Water in Beryl: A New State of the Water Molecule, Alexander I. Kolesnikov, George F. Reiter, Narayani Choudhury, Timothy R. Prisk, Eugene Mamontov, Andrey Podlesnyak, George Ehlers, Andrew G. Seel, David J. Wesolowski and Lawrence M. Anovitz, Phys. Rev. Lett., 116, 167802 (22 April 2016), DOI:10.1103/PhysRevLett.116.167802

Using neutron scattering and ab initio simulations, we document the discovery of a new “quantum tunneling state” of the water molecule confined in 5 Å channels in the mineral beryl, characterized by extended proton and electron delocalization. We observed a number of peaks in the inelastic neutron scattering spectra that were uniquely assigned to water quantum tunneling. In addition, the water proton momentum distribution was measured with deep inelastic neutron scattering, which directly revealed coherent delocalization of the protons in the ground state.

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Boron 11B Nuclear Isotopes Constrain CO2 Climate Forcing

by Tommy on 26/04/2016


Changing atmospheric CO2 concentration was the primary driver of early Cenozoic climate, Eleni Anagnostou, Eleanor H. John, Kirsty M. Edgar, Gavin L. Foster, Andy Ridgwell, Gordon N. Inglis, Richard D. Pancost, Daniel J. Lunt and Paul N. Pearson, Nature (25 April 2016), doi:10.1038/nature17423

The Early Eocene Climate Optimum (EECO, which occurred about 51 to 53 million years ago), was the warmest interval of the past 65 million years, with mean annual surface air temperature over ten degrees Celsius warmer than during the pre-industrial period. Subsequent global cooling in the middle and late Eocene epoch, especially at high latitudes, eventually led to continental ice sheet development in Antarctica in the early Oligocene epoch (about 33.6 million years ago). However, existing estimates place atmospheric carbon dioxide (CO2) levels during the Eocene at 500 – 3,000 parts per million, and in the absence of tighter constraints carbon–climate interactions over this interval remain uncertain. Here we use recent analytical and methodological developments to generate a new high-fidelity record of CO2 concentrations using the boron isotope (δ11B) composition of well preserved planktonic foraminifera from the Tanzania Drilling Project, revising previous estimates. Although species-level uncertainties make absolute values difficult to constrain, CO2 concentrations during the EECO were around 1,400 parts per million. The relative decline in CO2 concentration through the Eocene is more robustly constrained at about fifty percent, with a further decline into the Oligocene. Provided the latitudinal dependency of sea surface temperature change for a given climate forcing in the Eocene was similar to that of the late Quaternary period, this CO2 decline was sufficient to drive the well documented high- and low-latitude cooling that occurred through the Eocene. Once the change in global temperature between the pre-industrial period and the Eocene caused by the action of all known slow feedbacks (apart from those associated with the carbon cycle) is removed, both the EECO and the late Eocene exhibit an equilibrium climate sensitivity relative to the pre-industrial period of 2.1 to 4.6 degrees Celsius per CO2 doubling (66 percent confidence), which is similar to the canonical range (1.5 to 4.5 degrees Celsius), indicating that a large fraction of the warmth of the early Eocene greenhouse was driven by increased CO2 concentrations, and that climate sensitivity was relatively constant throughout this period.

Now you know you be fucked. It’s official. I’m just not seeing those electric cars on the road.

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Future Higgs Portal into Electroweak Cosmology Discussed

by Tommy on 22/04/2016


The Higgs Portal and Cosmology, Ketevi Assamagan, Chien-Yi Chen, John Paul Chou, David Curtin, Michael A. Fedderke, Yuri Gershtein, Xiao-Gang He, Markus Klute, Jonathan Kozaczuk, Ashutosh Kotwal, Steven Lowette, Jose Miguel No, Tilman Plehn, Jianming Qian, Michael Ramsey-Musolf, Alexei Safonov, Jessie Shelton, Michael Spannowsky, Shufang Su, Devin G. E. Walker, Stephane Willocq and Peter Winslow, Summarization of the landscape of possibilities surveyed at the “Unlocking the Higgs Portal” Workshop held at the Amherst Center for Fundamental Interactions (ACFI) in May 2014, Report number ACFI-T16-10 (18 April 2016)

Higgs portal interactions provide a simple mechanism for addressing two open problems in cosmology: dark matter and the baryon asymmetry. In the latter instance, Higgs portal interactions may contain the ingredients for a strong first order electroweak phase transition as well as new CP-violating interactions as needed for electroweak baryogenesis. These interactions may also allow for a viable dark matter candidate. We survey the opportunities for probing the Higgs portal as it relates to these questions in cosmology at the LHC and possible future colliders.

More flailing around in the dark for the dark sector.

You gotta start somewhere.

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Some Ultralight Axion Like Particles Excluded by Observation

by Tommy on 22/04/2016


Search for Spectral Irregularities due to Photon–Axionlike-Particle Oscillations with the Fermi Large Area Telescope, M. Ajello et al. (The Fermi-LAT Collaboration), Phys. Rev. Lett., 116, 161101 (20 April 2016), DOI:10.1103/PhysRevLett.116.161101

We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the γ-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5 × 10−12 GeV−1 for ALP masses 0.5 ≲ ma ≲ 5 neV at 95% confidence. The limits are competitive with the sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain the possibility that ALPs can reduce the γ-ray opacity of the Universe,

I haven’t read this paper, but this is a really poorly written abstract. We don’t know what ALPs are, we really don’t even know exactly what an axion is yet, and lattice QCD calculations already points to moderately heavy axions (not WIMP scale, ~ meV ~ keV ~), if they even exist at all.

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Happy Earth Day!

by Tommy on 22/04/2016
Lunar Reconnaissance Orbiter LRO Earth Moon Earthrise

Lunar Reconnaissance Orbiter LRO Earth Moon Earthrise

SpaceX – Launch and Land and Relaunch.

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Classical and Quantum Thermodynamic Heat Engines Probed

by Tommy on 17/04/2016


Periodic Thermodynamics of Open Quantum Systems, Kay Brandner and Udo Seifert (12 April 2016)

The thermodynamics of quantum systems coupled to periodically modulated heat baths and work reservoirs is developed. By identifying affinities and fluxes, the first and second law are formulated consistently. In the linear response regime, entropy production becomes a quadratic form in the affinities. Specializing to Lindblad-dynamics, we identify the corresponding kinetic coefficients in terms of correlation functions of the unperturbed dynamics. Reciprocity relations follow from symmetries with respect to time reversal. The kinetic coefficients can be split into a classical and a quantum contribution subject to a new constraint, which follows from a natural detailed balance condition. This constraint implies universal bounds on efficiency and power of quantum heat engines. In particular, we show that Carnot efficiency can not be reached whenever quantum coherence effects are present, i.e., when the Hamiltonian used for work extraction does not commute with the bare system Hamiltonian. For illustration, we specialize our universal results to a driven two-level system in contact with a heat bath of sinusoidally modulated temperature.

Udo Seifert continues to blaze a path with this. Here the result is that the most efficient coherent quantum energy up and down converters can do no useful work, and it appears that useful work extraction at maximum Carnot efficiency will also require an incoherent Fermi liquid and/or gas.

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Quantum Dualities Found in Arbitrarily Large Chern Numbers

by Tommy on 16/04/2016


Quantum Dualities and Quantum Anomalous Hall Phases with Arbitrary Large Chern Numbers, Tong Chern (28 March 2016)

Quantum duality is a far reaching concept in contemporary theoretical physics. In the present paper, we reveal the quantum dualities in quantum anomalous Hall (QAH) phases through concrete two bands Hamiltonian models. Our models can realize QAH phases with arbitrary large Chern numbers. In real materials these models may be realized by stacked n layer systems of c1 = 1 QAH insulators. The topological phase transitions that can change the Chern numbers are studied. And we investigate the gapless edge modes of our models in details, and find a new mechanism for the bulk boundary correspondence.

Again, this is so new and interesting all I can do is repeat it verbatim here.

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Engineering of Holographic Superconductivity Proposed

by Tommy on 16/04/2016


Engineering Holographic Superconductor Phase Diagrams, Jiunn-Wei Chen, Shou-Huang Dai, Debaprasad Maity and Yun-Long Zhang, Report Number MIT-CTP/4971 (27 March 2016)

We study how to engineer holographic models with features of a high temperature superconductor phase diagram. We introduce a field in the bulk which provides a tunable “doping” parameter in the boundary theory. By designing how this field changes the effective masses of other order parameter fields, desired phase diagrams can be engineered. We give examples of generating phase diagrams with phase boundaries similar to a superconducting dome and an anti-ferromagnetic phase by including two order parameter fields. We also explore whether the pseudo gap phase can be described without adding another order parameter field and discuss the potential scaling symmetry associated with a quantum critical point hidden under the superconducting dome in this phase diagram.

This is so interesting and timely that all I can do is urge you to slug your way through it.

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Hortonheardawho of Mars Rover Blog Image Processing Dies

by Tommy on 9/04/2016
Hortonheardawho Mars Surface Image

Hortonheardawho Mars Surface Image


I just heard that hortonheardawho passed away on February 25, 2016. Hort was a scientific and engineering genius who was the undisputed leader in Mars Rover image processing, posting his spectacular images on Mark Carey’s Mars Rover Blog. Mars Rover Blog forum software has always been super cranky, something left over from the CGI forum software days, and lately it’s starting to be hacked, but in its day it was the place to be for wild new hypotheses and crackpot ideas about Mars geology and the possibility of life on Mars. Hort was known for his identification and naming of the self ordering phenomena in the decaying soils of Mars – Hallucigenia and Psychedelia – aka SODs or Self Organizing Dust. His loss is great. But his work lives on.

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SpaceX Falcon 9 Booster Lands on a Drone Ship Barge

by Tommy on 8/04/2016
SpaceX Falcon 9 Booster Drone Ship

SpaceX Falcon 9 Booster Drone Ship

I feel another song coming on!

Let My People Go!

Update: April 12, 2016 – The ships are in port and the American Space Revolution has begun.

One if by land, two if by sea.

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Neutron Spectroscopy Reveals Hydrogen Rich Poles at Ceres

by Tommy on 7/04/2016
Ceres Dawn Hydrogen Distribution Neutron Spectroscopy

Ceres Dawn Hydrogen Distribution Neutron Spectroscopy

Ok then, forget Occator and the equator.

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Kaluza Geometry Favored by CERN LHC 750 GeV Resonance

by Tommy on 2/04/2016


Field Equations and Lagrangian for the Kaluza Metric Evaluated with Tensor Algebra Software, L. L. Williams, Journal of Gravity, 901870 (2015), DOI:10.1155/2015/901870

This paper calculates the Kaluza field equations with the aid of a computer package for tensor algebra, xAct. The xAct file is provided with this paper. We find that Thiry’s field equations are correct, but only under limited circumstances. The full five-dimensional field equations under the cylinder condition are provided here, and we see that most of the other references miss at least some terms from them. We go on to establish the remarkable Kaluza Lagrangian, and verify that the field equations calculated from it match those calculated with xAct, thereby demonstrating self-consistency of these results. Many of these results can be found scattered throughout the literature, and we provide some pointers for historical purposes. But our intent is to provide a definitive exposition of the field equations of the classical, five-dimensional metric ansatz of Kaluza, along with the computer algebra data file to verify them, and then to recover the unique Lagrangian for the theory. In common terms, the Kaluza theory is an “ω = 0″ scalar field theory, but with unique electrodynamic couplings.

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Dynamical Running Vacuum Models Favored Over Rigid ΛCDM

by Tommy on 2/04/2016


First evidence of running cosmic vacuum: challenging the concordance model, Joan Sola, Adria Gomez-Valent and Javier de Cruz Perez (5 Feb 2016)

Despite the fact that a rigid Λ-term is a fundamental building block of the concordance ΛCDM model, we show that a large class of cosmological scenarios with dynamical vacuum energy density ρΛ and/or gravitational coupling G, together with a possible non-conservation of matter, are capable of seriously challenging the traditional phenomenological success of the Λ-CDM. In this Letter, we discuss these “running vacuum models” (RVM’s), in which ρΛ=ρΛ(H) consists of a nonvanishing constant term and a series of powers of the Hubble rate. Such generic structure is potentially linked to the quantum field theoretical description of the expanding Universe. By performing an overall fit to the cosmological observables SNIα+BAO+H(z)+LSS+BBN+CMB (in which the WMAP9, Planck 2013 and Planck 2015 data are taken into account), we find that the RVM’s appear definitely more favored than the ΛCDM, namely at an unprecedented level of ∼4σ, implying that the ΛCDM is excluded at ∼99.99% c.l. Furthermore, the Akaike and Bayesian information criteria confirm that the dynamical RVM’s are strongly preferred as compared to the conventional rigid Λ-picture of the cosmic evolution.

This will be great for my report!

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The Image From Dawn At Ceres You’ve All Been Waiting For

by Tommy on 23/03/2016


Occator Crater panorama from low mapping orbit.


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Planet Ceres Sublimating Away Slowly – From Crust To Dust

by Tommy on 19/03/2016




Daily variability of Ceres’ Albedo detected by means of radial velocities changes of the reflected sunlight, P. Molaro, A. F. Lanza, L. Monaco, F. Tosi, G. Lo Curto, M. Fulle and L. Pasquini, Monthy Notices of the Royal Astronomical Society Letters (7 February 2016), DOI:10.1093/mnrasl/slw017

Bright features have been recently discovered by Dawn on Ceres, which extend previous photometric and Space Telescope observations. These features should produce distortions of the line profiles of the reflected solar spectrum and therefore an apparent radial velocity variation modulated by the rotation of the dwarf planet. Here we report on two sequences of observations of Ceres performed in the nights of 31 July, 26-27 August 2015 by means of the high-precision HARPS spectrograph at the 3.6-m La Silla ESO telescope. The observations revealed a quite complex behaviour which likely combines a radial velocity modulation due to the rotation with an amplitude of approx +/- 6 m/s and an unexpected diurnal effect. The latter changes imply changes in the albedo of Occator’s bright features due to the blaze produced by the exposure to solar radiation. The short-term variability of Ceres’ albedo is on timescales ranging from hours to months and can both be confirmed and followed by means of dedicated radial velocity observations.

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Dana Rohrabacher Introduces NASA Space Settlement Act

by Tommy on 18/03/2016


H.R. 4752 Space Exploration, Development, and Settlement Act of 2016 – March 16, 2016

A BILL To require the National Aeronautics and Space Administration to investigate and promote the exploration and development of space leading to human settlements beyond Earth, and for other purposes.

Maybe Dana Rorhabacher will figure out that science works! Even science he doesn’t like.

What he really needs to do is force this at the NASA federal charter level.

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United Launch Alliance ULA Engineering Executive Brett Tobey – Resigned and or is Fired – Effective Immediately

by Tommy on 17/03/2016


Wow. The cats are officially out of the bag.

Calling all cat herders!

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Shock Compression Phase Diagram of Diamond Refined

by Tommy on 16/03/2016


Nanosecond formation of diamond and lonsdaleite by shock compression of graphite, D. Kraus, A. Ravasio, M. Gauthier, D. O. Gericke, J. Vorberger, S. Frydrych, J. Helfrich, L. B. Fletcher, G. Schaumann, B. Nagler, B. Barbrel, B. Bachmann, E. J. Gamboa, S. Göde, E. Granados, G. Gregori, H. J. Lee, P. Neumayer, W. Schumaker, T. Döppner, R. W. Falcone, S. H. Glenzer and M. Roth, Nature Communications, 7, 10970 (14 March 2016), doi:10.1038/ncomms10970

The shock-induced transition from graphite to diamond has been of great scientific and technological interest since the discovery of microscopic diamonds in remnants of explosively driven graphite. Furthermore, shock synthesis of diamond and lonsdaleite, a speculative hexagonal carbon polymorph with unique hardness, is expected to happen during violent meteor impacts. Here, we show unprecedented in situ X-ray diffraction measurements of diamond formation on nanosecond timescales by shock compression of pyrolytic as well as polycrystalline graphite to pressures from 19 GPa up to 228 GPa. While we observe the transition to diamond starting at 50 GPa for both pyrolytic and polycrystalline graphite, we also record the direct formation of lonsdaleite above 170 GPa for pyrolytic samples only. Our experiment provides new insights into the processes of the shock-induced transition from graphite to diamond and uniquely resolves the dynamics that explain the main natural occurrence of the lonsdaleite crystal structure being close to meteor impact sites.

So lonsdaleite is back yet again, apparently.

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Quantum Electrodynamics Simulation by Superconducting Transmission Line Resonators

by Tommy on 16/03/2016


Zi-He Yang, Yan-Pu Wang, Zheng-Yuan Xue, Wan-Li Yang, Yong Hu, Jin-Hua Gao and Ying Wu (15 March 2016)

The concept of flat band plays an important role in strongly-correlated many-body physics. However, the demonstration of the flat band physics is highly nontrivial due to intrinsic limitations in conventional condensed matter materials. Here we propose a circuit quantum electrodynamics simulator of the 2D Lieb lattice exhibiting a flat middle band. By exploiting the simple parametric conversion method, we design a photonic Lieb lattice with in situ tunable hopping strengths in a 2D array of coupled superconducting transmission line resonators. Moreover, the flexibility of our proposal enables the immediate incorporation of both the artificial gauge field and the strong photon-photon interaction in a time- and site-resolved manner. To unambiguously demonstrate the synthesized flat band, we further investigate the observation of the flat band localization of microwave photons through the pumping and the steady-state measurements of only few sites on the lattice. Requiring only current level of technique and being robust against imperfections in realistic circuits, our scheme can be readily tested in experiments and may pave a new way towards the future realization of exotic photonic quantum Hall fluids including anomalous quantum Hall effect and bosonic fractional quantum Hall states without magnetic fields.

Just the other day we get a mathematical theory, now they intend to simulate it.

That was fast.

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Axion Electrodynamics Found in a Topological Insulator

by Tommy on 15/03/2016


Quantized Faraday and Kerr rotation and axion electrodynamics of the surface states of three-dimensional topological insulators, Liang Wu, M. Salehi, N. Koirala, J. Moon, S. Oh and N. P. Armitage (14 March 2016)

Topological insulators have been proposed to be best characterized as bulk magnetoelectric materials which show response functions quantized in terms of fundamental physical constants. It has been predicted that this manifests as Faraday and Kerr rotations that are quantized in units of the fine structure constant α =e2/2ϵ0hc. In this work we use a charge-transfer-doping preparation to lower the chemical potential of Bi2Se3 films into the bulk gap and as low as ∼ 30 meV above the Dirac point, and then probe their low-energy electrodynamic response with high-precision time-domain terahertz polarimetry. As a function of field, a crossover from semi-classical cyclotron resonance to a quantum regime was observed. In this regime, although the DC transport is still semi-classical, we find quantized Faraday and Kerr rotations the size of which is set by the fine structure constant, which provides evidence for the long-sought axion electrodynamics and the topological magnetoelectric effect of the topological insulator’s surface states. Among other aspects, the unique time structure used in such measurements allow us a direct measure of the fine structure constant based on a topological invariant of a solid-state system for the first time.

Wow, it really is Pi Day!

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Field Theoretic Approach to Quantum Crystal Melting

by Tommy on 15/03/2016


Dual gauge field theory of quantum liquid crystals in two dimensions, Aron J. Beekman, Jaakko Nissinen, Kai Wu, Ke Liu, Robert-Jan Slager, Zohar Nussinov, Vladimir Cvetkovic andJan Zaanen (14 March 2016)

We present a self-contained review of the theory of dislocation-mediated quantum melting at zero temperature in two spatial dimensions. The theory describes the liquid-crystalline phases with spatial symmetries in between a quantum crystalline solid and an isotropic superfluid: quantum nematics and smectics. It is based on an Abelian-Higgs-type duality mapping of phonons onto gauge bosons (“stress photons”), which encode for the capacity of the crystal to propagate stresses. Dislocations and disclinations, the topological defects of the crystal, are sources for the gauge fields and the melting of the crystal can be understood as the proliferation (condensation) of these defects, giving rise to the Anderson-Higgs mechanism on the dual side. For the liquid crystal phases, the shear sector of the gauge bosons becomes massive signaling that shear rigidity is lost. Resting on symmetry principles, we derive the phenomenological imaginary time actions of quantum nematics and smectics and analyze the full spectrum of collective modes. The quantum nematic is a superfluid having a true rotational Goldstone mode due to rotational symmetry breaking, and the origin of this ‘deconfined’ mode is traced back to the crystalline phase. The two-dimensional quantum smectic turns out to be a dizzyingly anisotropic phase with the collective modes interpolating between the solid and nematic in a non-trivial way. We also consider electrically charged bosonic crystals and liquid crystals, and carefully analyze the electromagnetic response of the quantum liquid crystal phases. In particular, the quantum nematic is a real superconductor and shows the Meissner effect. Their special properties inherited from spatial symmetry breaking show up mostly at finite momentum, and should be accessible by momentum-sensitive spectroscopy.

Can anyone say … quantum gravity?

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Superconductivity Found at 0.53 mK in Ultra Pure Bismuth

by Tommy on 15/03/2016


Discovery of superconductivity in pure Bi single crystal, Om Prakash, Anil Kumar, A. Thamizhavel and S. Ramakrishnan (14 March 2016)

Semimetal Bi has been studied extensively for more than a century \cite{1} and still continues to draw enormous scientific interest due to its anomalous electronic properties. In fact, Bi was the first element whose Fermi surface was experimentally measured \cite{2} and provided the basis to determine that of other metals. Many of the outstanding properties of bulk Bi are linked to its peculiar electronic structure. Bi has small electron and hole pockets and a very small density of states (DOS) at the Fermi level. Due to low carrier density, Coulomb screening in Bi is much weaker than metals. Inter-atomic bonding in Bi has a strong directional component leading to a layered crystal structure with alternating weak and strong inter-layer bonds. Such a structure is a crucial factor to observe many quantum phenomena rather easily in Bi. However, superconductivity, a macroscopic quantum phenomena has never been observed in bulk Bi under ambient pressure to date. In this work, we report first ever observation of bulk superconductivity in a high purity (99.9999\%) single crystal of Bi at 0.53~mK under ambient pressure. This discovery makes Bi as the superconductor with the lowest carrier density thus, breaking the record held by doped SrTiO3 \cite{3} for nearly 50 years.

Happy Pi Day!

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Momentum Space Topological Invariants By Green’s Functions

by Tommy on 14/03/2016


Wigner transformation, momentum space topology, and anomalous transport, M. A. Zubkov (11 March 2016)

Using derivative expansion applied to the Wigner transform of the two – point Green function we analyse the anomalous quantum Hall effect (AQHE), and the chiral magnetic effect (CME). The corresponding currents are proportional to the momentum space topological invariants. We reproduce the conventional expression for the Hall conductivity in 2+1 D. In 3+1 D our analysis allows to explain systematically the AQHE in topological materials including Weyl semimetals. At the same time using this method we prove, that the equilibrium CME is absent in the wide class of solids, as well as in the properly regularized relativistic quantum field theory.

I like this approach a lot. This is moving in the right direction.

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Cosmic Evolution and the Origin of Life – Autobiogenesis

by Tommy on 12/03/2016


The Cosmic Evolution of Autobiogenesis (In Progress)

I have recently redefined the scientific term ‘autobiogenesis’ to mean the consistent and widespread development of life on small, water covered terrestrial planets within the habitable zones of stable yellow metal rich stars, as opposed to ‘abiogenesis’, which I now define as the singular, one time only development of life on this planet. Formerly, this rarely used term referred to the highly improbable development of life by way of randomly reacting biomolecules within our terrestrial planet’s ocean. Recent developments in stochastic thermodynamics, tested experimentally with colloidal dynamics, indicates that this highly improbable development of life within a biological soup is not the appropriate approach to the evolution of life.

A superior alternative to the origin of cellular metabolism has recently emerged, involving the energy gradients in the vicinity of seafloor alkaline hydrothermal vents, where inorganic clays contain a variety of mineral catalyst surfaces within microporous containment vesicles. Although the existence of a highly enriched biological soup composed of many protobiological decay products can also serve as a secondary pathway to the evolution of free floating biological replicators, the hypothesis of random chemical reactions within a biological soup doesn’t adequately represent any modern thinking about plausible theories on the origin of life, which necessitates (r) evolutionary ideas.

Evidence for autobiogenesis on suitably stable terrestrial planets is persuasive. Besides the unforgiving spectroscopic evidence that radioactive atomic nuclides formed by nucleosynthesis in stellar processes are identical across the observable universe, it also appears that the development of life on this planet was particularly rapid, and survived multiple periods of intense post formation planetoid and asteroid bombardment events, many of which were undoubtedly easily capable of planet wide life sterilization.

Given the widespread and now nearly indisputable evidence for autobiogenesis on terrestrial planets as I have defined the term, the time has now come to discuss the evolutionary history of its development, from both cosmological perspectives and through condensed matter physics theories and experiments. From condensed matter physics perspectives recent breakthroughs in quantum topological physics have made the simulation of these concepts possible in tabletop experiments, yet there remains glaring gaps of knowledge in quantum cosmology and high energy particle physics, such as relationships between quantum field theories of the standard model and the equations of general relativity. Large fractions of the mass and energy of the universe remain missing from theory almost entirely while the observational demonstration of its existence is irrefutable. Thus we are confronted with yet another crisis in physics.

In this essay I will discuss and analyze what is known, and not known, and outline a path to discovery.

The existence of biological life on the planet Earth is the result of a long sequence of evolutionary steps extending back through time, to an era of cosmic history that is hidden from direct observations by the cosmic microwave background emissions at roughly 2.72548 ± 0.00057 K which peaks at ~160.2 GHz. Besides invoking mathematical theories, numerical computations and direct experimental simulations, the only other observational means of accessing this early era of cosmic evolution, is via high energy physics experiments using large electron, proton and ion particle accelerators, and through the indirect observations of black holes and their event horizons through their electromagnetic spectral emissions, and now more recently through their gravitational wave emissions, using large laser interferometers.

Recent LIGO detection of a pair of merging black holes seems to indicate that spacetime has a deeper topological structure, in addition to the ordinary globally flat to slightly curved geometry – pushed to the extreme as one approaches the event horizon of a black hole. That broken geometry of spacetime is hidden by the event horizon much like a quantum critical point is hidden by a superconducting dome. Topological phase transitions are required for two rotating and revolving black holes to merge into one.

Deeper topological structures of spacetime can only be simulated in modern condensed matter systems. Axion electrodynamics, Chern Simons physics, Kitaev hierarchies, transport anomalies, gravitational couplings to bulk – boundary correspondences, Dirac, Weyl and Majorana fermions and other exotic excitations, as well as a wide variety of new composite bosons and quasiparticle excitations, are now all accessible in a consistent framework, requiring at most liquid helium temperatures for examination. Ultra cold atomic system manipulations in laser trapping experiments have already revolutionized our understanding of ambient condensed matter systems and will continue to contribute heavily to the field, providing the alternative perspectives and techniques necessary to cross check and verify any results. Condensed matter simulations of gravitational physics and quantum field theories will be the primary engines of scientific progress moving forward, for this current theoretical impasse to be fully resolved.

The cosmic microwave background radiation has been perhaps the most informative limit in regards to our knowledge of the larger cosmic universe. Besides its mere existence by discovery, it has been the subject of intense high resolution study, both ground based and by satellite.

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Geometric Contribution to Superfluid Spectral Weight Proposed

by Tommy on 11/03/2016


Geometric origin of superfluidity in the Lieb lattice flat band, Aleksi Julku, Sebastiano Peotta, Tuomas Vanhala, Dong-Hee Kim and Päivi Törmä (10 March 2016)

The ground state and transport properties of the Lieb lattice flat band in the presence of an attractive Hubbard interaction are considered. It is shown that the superfluid weight can be large even for an isolated and strictly flat band. Moreover the superfluid weight is proportional to the interaction strength and to the quantum metric, a band structure invariant obtained from the flat-band Bloch functions. These predictions are amenable to verification with ultracold gases and may explain the anomalous behaviour of the superfluid weight of high-Tc superconductors

The force is strong with this one.

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New Space Subgroup Symmetric Fermion Excitations Predicted

by Tommy on 11/03/2016


New Fermions, Barry Bradlyn, Jennifer Cano, Zhijun Wang, R. J. Cava and B. Andrei Bernevig (9 March 2016)

In quantum field theory, we learn that fermions come in three varieties: Majorana, Weyl, and Dirac. In this paper, we show that this is not a complete classification. We find the types of crystal symmetry-protected free fermionic excitations that can occur in condensed matter systems, going beyond the classification of Majorana, Weyl, and Dirac particles. We exhaustively classify linear and quadratic 3-, 6- and 8- band crossings stabilized by space group symmetries in solid state systems with spin-orbit coupling and time-reversal symmetry. Several distinct types of fermions arise, differentiated by their degeneracies at and along high symmetry points, lines, and surfaces. For each new class of fermion, we analyze its topological properties by constructing the low-energy effective Hamiltonian and comment on any possible experimental signatures. Some notable consequences of these fermions are the presence of Fermi arcs in non-Weyl systems, the fermionic spin-1 generalization of a Weyl fermion, and the existence of Dirac lines. In addition, we present 18 candidate materials that should realize these exotic fermions, as verified by ab-initio calculations. Finally, we comment on experimental investigations that are currently underway.

Ok. This should be fun. There is a whole lotta weirdness going on.

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Donald Trump and Ted Cruz are American Fascists

by Tommy on 10/03/2016
Donald Trump Ted Cruz American Fascism

Donald Trump Ted Cruz American Fascism

It must be the lead in the water and air.

Vote for Bernie Sanders. He cares.

Update: A Trump supporter chimes in.


Tom Rennick • 4 hours ago

Once Trump wins the presidency, I do know this: it will be open season on leftists, liberals, Cultural Marxists, RINO’s, Democrats, Mexicans, and any others who opposed him. All had better watch their backs. Payback is coming.

That’s American fascism on full display.

Update 2: There is more.


Trump Supporter Who Punched Protester: ‘Next Time, We Might Have To Kill Him’

Thank you George Bush.

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NASA Press Release Claims SLS SSMEs To Fly In Space

by Tommy on 10/03/2016


“This is what the testing we do is all about – preparing engines to fly into space,” Stennis Space Center Director Rick Gilbrech said.

Rick Gilbrech is an asshole and a fraud, and NASA’s SLS/Orion program is fraudulent.

The engine will spend 30 minutes in a sub orbital flight, not even making it to orbit, and then it, and the rocket carrying it, will burn up in the atmosphere – their remains dumped in the ocean.

That’s quite a ‘flight’, Rick. Greatness and a paycheck surely awaits you.



Let Space Travel Flourish, Leave It to the Cranks and Crackpots, John Tamny, Real Clear Markets (10 March 2016)

Precisely because travel into space and beyond sometimes seems an impossible dream, we want government as far away from the process as possible. Turning a seemingly unthinkable trip to Mars into something real requires just the kind of outside-the-box thinking that is most likely to emerge from those who appear to have originated there. We want the “cranks” and the “crackpots” pursuing inconceivable advances in space, as opposed to the individuals and businesses that know a congressman or senator.

That’s what’s exciting about the entrance of entrepreneurs like Jeff Bezos (Blue Origin) and Elon Musk (SpaceX) into the space exploration game. Once business outsiders themselves, they’re bringing unquenchable energy and unconventional thinking to a concept held back for too long by stodgy government officials. Both can point to successful rocket launches into space over the last few months.

That’s successful REUSABLE rocket launches, Mr. Tamny.

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Quantitative Analysis Points to Topological Cuprate Physics

by Tommy on 10/03/2016



Quantitative determination of pairing interactions for high-temperature superconductivity in cuprates, Jin Mo Bok, Jong Ju Bae, Han-Yong Choi, Chandra M. Varma, Wentao Zhang, Junfeng He, Yuxiao Zhang, Li Yu and X. J. Zhou, Science Advances, Vol 2, No. 3 (04 March 2016), DOI:10.1126/sciadv.1501329

A profound problem in modern condensed matter physics is discovering and understanding the nature of fluctuations and their coupling to fermions in cuprates, which lead to high-temperature superconductivity and the invariably associated strange metal state. We report the quantitative determination of normal and pairing self-energies, made possible by laser-based angle-resolved photoemission measurements of unprecedented accuracy and stability. Through a precise inversion procedure, both the effective interactions in the attractive d-wave symmetry and the repulsive part in the full symmetry are determined. The latter is nearly angle-independent. Near Tc, both interactions are nearly independent of frequency and have almost the same magnitude over the complete energy range of up to about 0.4 eV, except for a low-energy feature at around 50 meV that is present only in the repulsive part, which has less than 10% of the total spectral weight. Well below Tc, they both change similarly, with superconductivity-induced features at low energies. Besides finding the pairing self-energy and the attractive interactions for the first time, these results expose the central paradox of the problem of high Tc

This has been out on the ArXiv for a while now, and it’s now published and starting to get a lot of press from its press release, which I notice has no link to the actual published article. Figures.

I think ‘exclusive’ is a too strong of word to use in this case, but given what I have learned in the last six months about topological physics and nanoscopic phase separation I am beginning to think he has a point. There is more to this story than a reader of the press release would see.

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