James Cameron Wants More Babies and More Children

by Tommy on 29/07/2016

Guide me O’ Billionaire Film Director and Important Personalities!

James Cameron is not living in reality.

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Autobiogenesis and the Origin of Life – Hydrothermal Vents and Hot Springs

by Tommy on 28/07/2016


The physiology and habitat of the last universal common ancestor, Madeline C. Weiss, Filipa L. Sousa, Natalia Mrnjavac, Sinje Neukirchen, Mayo Roettger, Shijulal Nelson-Sathi and William F. Martin, Nature Microbiology 1, Article number: 16116 (25 July 2016), doi:10.1038/nmicrobiol.2016.116

The concept of a last universal common ancestor of all cells (LUCA, or the progenote) is central to the study of early evolution and life’s origin, yet information about how and where LUCA lived is lacking. We investigated all clusters and phylogenetic trees for 6.1 million protein coding genes from sequenced prokaryotic genomes in order to reconstruct the microbial ecology of LUCA. Among 286,514 protein clusters, we identified 355 protein families (∼0.1%) that trace to LUCA by phylogenetic criteria. Because these proteins are not universally distributed, they can shed light on LUCA’s physiology. Their functions, properties and prosthetic groups depict LUCA as anaerobic, CO2-fixing, H2-dependent with a Wood–Ljungdahl pathway, N2-fixing and thermophilic. LUCA’s biochemistry was replete with FeS clusters and radical reaction mechanisms. Its cofactors reveal dependence upon transition metals, flavins, S-adenosyl methionine, coenzyme A, ferredoxin, molybdopterin, corrins and selenium. Its genetic code required nucleoside modifications and S-adenosyl methionine-dependent methylations. The 355 phylogenies identify clostridia and methanogens, whose modern lifestyles resemble that of LUCA, as basal among their respective domains. LUCA inhabited a geochemically active environment rich in H2, CO2 and iron. The data support the theory of an autotrophic origin of life involving the Wood–Ljungdahl pathway in a hydrothermal setting.


The Cosmic Evolution of Autobiogenesis

That’s a really hot cup of tea.

Godzillions of them.

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Halide Decorated Plumbene Monolayer is a Giant Gap Quantum Spin Hall Insulator

by Tommy on 23/07/2016


Unexpected Giant-Gap Quantum Spin Hall Insulator in Chemically Decorated Plumrbene Monolayer. Hui Zhao, Chang-wen Zhang, Wei-xiao Ji, Run-wu Zhang, Sheng-shi Li, Shi-shen Yan, Bao-min Zhang, Ping Li, and Pei-ji Wang, Sci Rep. 2016; 6: 20152 (2 February 2016), doi:10.1038/srep20152

Quantum spin Hall (QSH) effect of two-dimensional (2D) materials features edge states that are topologically protected from backscattering by time-reversal symmetry. However, the major obstacles to the application for QSH effect are the lack of suitable QSH insulators with a large bulk gap. Here, we predict a novel class of 2D QSH insulators in X-decorated plumbene monolayers (PbX; X = H, F, Cl, Br, I) with extraordinarily giant bulk gaps from 1.03 eV to a record value of 1.34 eV. The topological characteristic of PbX mainly originates from spx,y band inversion related to the lattice symmetry, while the effect of spin-orbital coupling (SOC) is only to open up a giant gap. Their QSH states are identified by nontrivial topological invariant Z2 = 1, as well as a single pair of topologically protected helical edge states locating inside the bulk gap. Noticeably, the QSH gaps of PbX are tunable and robust via external strain. We also propose high-dielectric-constant BN as an ideal substrate for the experimental realization of PbX, maintaining its nontrivial topology. These novel QSH insulators with giant gaps are a promising platform to enrich topological phenomena and expand potential applications at high temperature.

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The Witten Effect in Topological Superconductors

by Tommy on 22/07/2016


Josephson currents induced by the Witten effect, Flavio S. Nogueira, Zohar Nussinov and Jeroen van den Brink (14 July 2016)

We reveal the existence of a new type of topological Josephson effect involving type II superconductors and three-dimensional topological insulators as tunnel junctions. We predict that vortex lines induce an electromagnetic variant of the Witten effect that is the consequence of the axion electromagnetic response of the topological insulator. If an external magnetic field is applied perpendicular to the junction, the Witten effect induces an AC Josephson effect in absence of any external voltage. We derive a number of further experimental consequences and propose potential setups where these {quantized, flux induced, Witten} effects may be observed.

See also: http://arxiv.org/abs/1601.03382

Duality of a compact topological superconductor model and the Witten effect. Flavio S. Nogueira, Zohar Nussinovand Jeroen van den Brink (21 July 2016)

We consider a compact abelian Higgs model in 3+1 dimensions with a topological axion term and construct its dual theories for both bulk and boundary at strong coupling. The model may be viewed as describing a superconductor with magnetic monopoles, which can also be interpreted as a field theory of a topological Mott insulator. We show that this model is dual to a non-compact topological field theory of particles and vortices. It has exactly the same form of a model for superconducting cosmic strings with an axion term. We consider the duality of the boundary field theory at strong coupling and show that in this case θ is quantized as −8πn/m where n and m are the quantum numbers associated to electric and magnetic charges. These topological states lack a non-interacting equivalent.

Finally something that looks like it might work in practice.

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Probing Photonic Lattices and Artificial Quantum Materials – Hamiltonian Tomography

by Tommy on 21/07/2016


Hamiltonian Tomography of Photonic Lattices, Ruichao Ma, Clai Owens, Aman LaChapelle, David I. Schuster, Jonathan Simon (18 July 2016)

In this letter we introduce a novel approach to Hamiltonian tomography of non-interacting tight-binding photonic lattices. To begin with, we prove that the matrix element of the low-energy effective Hamiltonian between sites i and j may be obtained directly from Sij(ω), the (suitably normalized) two-port measurement between sites i and j at frequency ω. This general result enables complete characterization of both on-site energies and tunneling matrix elements in arbitrary lattice networks by spectroscopy, and suggests that coupling between lattice sites is actually a topological property of the two-port spectrum. We further provide extensions of this technique for measurement of band-projectors in finite, disordered systems with good flatness ratios, and apply the tool to direct real-space measurement of the Chern number. Our approach demonstrates the extraordinary potential of microwave quantum circuits for exploration of exotic synthetic materials, providing a clear path to characterization and control of single-particle properties of Jaynes-Cummings-Hubbard lattices. More broadly, we provide a robust, unified method of spectroscopic characterization of linear networks from photonic crystals to microwave lattices and everything in-between.

Another great result from the University of Chicago.

I wonder if anyone at the ICHEP will figure it out?

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Psychotic Corrupt NASA Veterans Plead For More Pork

by Tommy on 15/07/2016

NASA at a Crossroads: Reasserting American Leadership in Space Exploration


After 15 years of NASA bullshit this is all getting a little old. With nothing at all to show for it.

Fuck NASA. This is going to be an ugly scene and great fun to watch.

Not the hearing, the indictments. I didn’t watch the hearing.

I don’t watch them anymore. What’s the point?

It’s just more murder confessions.

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Lattice Gauge Theory Computational QCD Axion Cosmology

by Tommy on 14/07/2016


The topological susceptibility in finite temperature QCD and axion cosmology, Peter Petreczky, Hans-Peter Schadler and Sayantan Sharma (9 June 2016)

We study the topological susceptibility in 2+1 flavor QCD above the chiral crossover transition temperature using Highly Improved Staggered Quark action and several lattice spacings, corresponding to temporal extent of the lattice, Nτ = 6, 8, 10 and 12. We observe very distinct temperature dependencies of the topological susceptibility in the ranges above and below 250 MeV. While for temperatures above 250 MeV, the dependence is found to be consistent with dilute instanton gas approximation, at lower temperatures the fall-off of topological susceptibility is milder. We discuss the consequence of our results for cosmology wherein we estimate the bounds on the axion decay constant and the oscillation temperature if indeed the QCD axion is a possible dark matter candidate.

This is some followup exploratory work in this field that I blogged earlier.

It shouldn’t be too long now.

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The Younger Dryas Glacial Lake Agassiz Meltwater Discharge Masters Thesis of David J. Leydet at Oregon State University

by Tommy on 14/07/2016


Eastward Routing of Glacial Lake Agassiz Runoff caused the Younger Dryas Cold Event, David J. Leydet, Masters Thesis, College of Earth, Ocean and Atmospheric Sciences, Anders E. Carlson, Advisor, Oregon State University (3 May 2016)

The purpose of this thesis is to analyze an abrupt case of climate change in the past as a means to understand the mechanisms that force climate change. By looking to past analogs of climate change, we hopefully will gain an understanding of these events, which could be used to further our understanding of future climate change. In this light, I analyze the case of the Younger Dryas (YD), an abrupt cooling event that occurred from ~ 12.9 ka to ~ 11.7 ka. We investigate several hypotheses regarding the cause of the YD and attempt to determine the forcing mechanism for this abrupt cooling event. I use 10Be surface exposure dating as our method for dating retreat of the Laurentide Ice Sheet from the eastern outlets of glacial Lake Agassiz, a large pro-glacial lake that formed during the last deglaciation whose drainage into the North Atlantic is hypothesized to have caused the YD via a slowing of ocean overturning circulation. I find that the eastern outlets of glacial Lake Agassiz begin to deglaciate at 14.0 ± 0.3 ka with ice retreating from the key Lake Kaministikwia outlet at 13.0 ± 0.3 ka, concurrent with the onset of the YD. I also date retreat from the Steep Rock moraine at 13.8 ± 0.2 ka and retreat from the Marks moraine by 11.0 ± 0.4 ka. I use our chronology along with other terrestrial and marine proxies to reconstruct the meltwater routing history of Lake Agassiz. Specifically, the Gulf of St. Lawrence isotopic record indicates meltwater routing through Eastern Outlets, peaking at ~ 12.6 ka. Subsequently, the isotopic record of the Arctic Ocean near the mouth of the Mackenzie River indicates meltwater routing beginning at ~ 12.4 ka and peaking at 12.2 ka.

I argue that the timing of these meltwater pathways support the hypotheses that the YD was caused by freshwater forcing, weakening the Atlantic Meriodional Overturning Circulation, and thus cooling the climate of the Northern Hemisphere. The results demonstrate the importance of meltwater routing on the climate system and will be important in understanding the implications of future ice sheet-oceanclimate interactions in a climatically changing world.

This seems moderately definitive. I wonder how long it will last?

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Archimedes Space Architecture – Tsiolkovsky Launch Vehicle

by Tommy on 8/07/2016

These will be wrap up papers.

Archimedes Space Architecture

http://lifeform.net/tsiolkovsky/Archimedes.pdf (fixed)

Tsiolkovsky Reusable Launch Vehicles


Hopefully finished before September.

Yes, that’s a wrap, folks.

Update: I fixed the URL. This has taken so long I now need reading glasses.

I’m beginning to wonder if I will ever get to fly.

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Tabletop Simulation of Universe Cosmic Inflation Proposed

by Tommy on 8/07/2016


The universe on a table top: engineering quantum decay of a relativistic scalar field from a metastable vacuum, Oleksandr Fialko, Bogdan Opanchuk, Andrei I. Sidorov, Peter D. Drummond and Joachim Brand (6 July 2016)

The quantum decay of a relativistic scalar field from a metastable state (“false vacuum decay”) is a fundamental idea in quantum field theory and cosmology. This occurs via local formation of bubbles of true vacuum with their subsequent rapid expansion. It can be considered as a relativistic analog of a first-order phase transition in condensed matter. We propose an experimental test of false vacuum decay using an ultra-cold spinor Bose gas. A false vacuum for the relative phase of two spin components, serving as the unstable scalar field, is generated by means of a modulated linear coupling of the spin components. We analyze the system theoretically using the functional integral approach and show that various microscopic degrees of freedom in the system, albeit leading to dissipation in the relative phase sector, will not hamper the observation of the false vacuum decay in the laboratory. This is substantiated by numerical simulations, which demonstrate the spontaneous formation of true vacuum bubbles with realistic parameters and time-scales.

See also: http://arxiv.org/abs/1408.1163


Fate of the false vacuum: towards realization with ultra-cold atoms, O. Fialko, B. Opanchuk, A. I. Sidorov, P. D. Drummond and J. Brand, Europhys. Lett., 110, 56001 (22 June 2015), doi:10.1209/0295-5075/110/56001

Quantum decay of a relativistic scalar field from a false vacuum is a fundamental idea in quantum field theory. It is relevant to models of the early Universe, where the nucleation of bubbles gives rise to an inflationary universe and the creation of matter. Here we propose a laboratory test using an experimental model of an ultra-cold spinor Bose gas. A false vacuum for the relative phase of two spin components, serving as the unstable scalar field, is generated by means of a modulated radio-frequency coupling of the spin components. Numerical simulations demonstrate the spontaneous formation of true vacuum bubbles with realistic parameters and time-scales.

This sounds like a good start.

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Cuprate Thin Film Reveals a Nodeless High-Tc Pairing Gap

by Tommy on 8/07/2016


Nodeless pairing in superconducting copper-oxide monolayer films on Bi2Sr2CaCu2O8+δ, Yong Zhong, Yang Wang, Sha Han, Yan-Feng Lv, Wen-Lin Wang, Ding Zhang, Hao Ding, Yi-Min Zhang, Lili Wang, Ke He, Ruidan Zhong, John A. Schneeloch, Gen-Da Gu, Can-Li Song, Xu-Cun Ma and Qi-Kun Xue (7 July 2016)

The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most effective approaches is to investigate directly the superconducting CuO2 layers. Here, by growing CuO2 monolayer films on Bi2Sr2CaCu2O8+δ substrates, we identify two distinct and spatially separated energy gaps centered at the Fermi energy, a smaller U-like gap and a larger V-like gap on the films, and study their interactions with alien atoms by low-temperature scanning tunneling microscopy. The newly discovered U-like gap exhibits strong phase coherence and is immune to scattering by K, Cs and Ag atoms, suggesting its nature as a nodeless superconducting gap in the CuO2 layers, whereas the V-like gap agrees with the well-known pseudogap state in the underdoped regime. Our results support an s-wave superconductivity in Bi2Sr2CaCu2O8+δ, which, we propose, originates from the modulation-doping resultant two-dimensional hole liquid confined in the CuO2 layers.

Ok. Rodger Dodger. I read you fine. That’s affirmative. Over.

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Axion Higgs Quantum Critical Gravitational Black Hole Collapse

by Tommy on 2/07/2016
CERN LHC Cosmic Wormhole Portal Higher Dimensions

CERN LHC Cosmic Wormhole Portal


Or rather it’s the graviton – axion – Higgs. It doesn’t seem to be gravitons – Higgs – axions.

One would have to calculate when quantum critical black hole collapse would occur, using results from tabletop axion – Higgs simulators and cold atom modelling, and a thorough analysis of cosmological parameters. Certainly LIGOs are going to be super helpful here.

Offhand I would say under 100 TeV. Probably 1000 TeV would be doable.

Given the costs, guidance will be helpful.

Tread lightly my friends.

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Dawn To Possibly Maybe Fly By Asteroid 145 Adeona

by Tommy on 1/07/2016

145 Adeona – a big average yukky carbonaceous rock dirt blob.

Happy Post Asteroid Day!

Update: I guess not.

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Symmetry Protected Bosonic Thermal Heat Currents Explored

by Tommy on 30/06/2016


Topological Heat Transport and Symmetry-Protected Boson Currents, Ángel Rivas and Miguel A. Martin-Delgado (24 June 2016)

The study of non-equilibrium properties in topological systems is of practical and fundamental importance. Here, we analyze the stationary properties of a two-dimensional boson topological insulator coupled to two thermal baths in the quantum open-system formalism. Novel phenomena appear like chiral edge heat currents that are the out-of-equilibrium counterparts of the zero-temperature edge currents. We find the new set of discrete symmetries that protect these topological heat currents, differing from the zero-temperature limit. Remarkably, one of these currents flows opposite to the decreasing external temperature gradient. As the starting point, we consider the case of a single external reservoir showing prominent results like thermal erasure effects and topological thermal currents. Our results are experimentally accessible with platforms like photonics systems and optical lattices.

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Topological Phononics and Phonon Diodes Proposed

by Tommy on 28/06/2016


Topological Phononics and Phonon Diode, Yizhou Liu, Yong Xu, Shou-Cheng Zhang abd Wenhui Duan (26 June 2016)

Generalizing the concept of topology from electrons to phonons could bring in an intriguing emerging field of “topological phononics”. For this purpose we propose a Schr\”odinger-like equation of phonons where topology-related quantities, time reversal symmetry (TRS) and its breaking can be naturally introduced. A Haldane model of phonons for a two-dimensional honeycomb lattice is then developed to describe the interplay of symmetry and quantum (anomalous) Hall-like phonon states. The nontrivial topological phase supports one-way gapless edge states within the bulk gap, which can conduct phonons without dissipation. Moreover, breaking inversion symmetry and TRS simultaneously is suggested to open a route for valley phononics and phonon diode. The findings could help design unprecedented new phononic devices.

This is exactly what I needed to complete the design of the ZT = 4 thermoelectric device.

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Topological Lifshitz Transitions By Grigory G. E. Volovik

by Tommy on 28/06/2016


Topological Lifshitz Transitions, G.E. Volovik (27 June 2016)

Different types of Lifshitz transitions are governed by topology in momentum space. They involve the topological transitions with the change of topology of Fermi surfaces, Weyl and Dirac points, nodal ines, and also the transitions between the fully gapped states.

The future has most definitely arrived.

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A Basic Review of the Quantum Hall Effect

by Tommy on 23/06/2016


Lectures on the Quantum Hall Effect, David Tong (21 June 2016)

The purpose of these lectures is to describe the basic theoretical structures underlying the rich and beautiful physics of the quantum Hall effect. The focus is on the interplay between microscopic wavefunctions, long-distance effective Chern-Simons theories, and the modes which live on the boundary. The notes are aimed at graduate students in any discipline where ℏ = 1. A working knowledge of quantum field theory is assumed.


1. The Basics (Landau levels and Berry phase).
2. The Integer Quantum Hall Effect.
3. The Fractional Quantum Hall Effect.
4. Non-Abelian Quantum Hall States.
5. Chern-Simons Theories.
6. Edge Modes.

These lectures were given at TIFR, Mumbai. Individual chapters can be downloaded from this http URL. The notes on the course webpage will be updated more frequently than those on the arXiv.

David Tong: Lectures on the Quantum Hall Effect (With Web and ArXiv References)


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Abram Steiner – The Universal Hydroponic Nutrient Solution

by Tommy on 23/06/2016
Abram Steiner Hydroponics

Abram Steiner Hydroponics


Vale, Bram Steiner, Soilless culture pioneer Abram Steiner, 1920-2016

Rock Donnan, Practical Hydroponics and Greenhouses, No. 166 (April 2016)

This was the first real science project that I did, besides the mathematics. I had hit the ground running (hobbling in crutches as I recall) in 1978, after finally making the move to the farm, and was easily doing these calculations in first year first semester general chemistry class, By 1979 I had it all worked out, and quickly verified it all by flame photospectroscopy. It soon went awry.

I only recently reviewed the idea in this short little essay.


Which led directly to the GroX.

Mars GroX will be lighter.

http://grok.lifeform.org (fixed)


Nutrient Solutions for Hydroponic Systems, Libia I. Trejo-Téllez and Fernando C. Gómez-Merino, Hydroponics – A Standard Methodology for Plant Biological Researches, Dr. Toshiki Asao (Ed.) (23 March 2012)

Finally it’s all back on track.

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CERN LHC ATLAS CMS Rumor – 750 GeV Bump Not Seen

by Tommy on 22/06/2016


I can only assess these rumors a rumor credibility index of one unit Motl. It doesn’t look good.

That’s ok with me, as I originally stated that I don’t need this pseudo particle for what I propose.


This is already a done deal. Up next for me?

I am open to job offers.

D.C., Seattle, Denver.




In that order.

Anywhere but Wisconsin.

Update: Get your job offers in before I sign Kermit the Frog’s rich and famous contract!

Update 2: Miss Piggy has been leaving a lot of messages on my voice mail, so hurry up!

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Large Nearby Resonant Quasi Satellite Asteroid Near Earth

by Tommy on 17/06/2016
Asteroid Earth Quasi Satellite 2016 HO3

Asteroid Earth Quasi Satellite 2016 HO3


2016 HO3. As large as 100 meters in diameter. As close as 9 million miles. Perfect.

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The Gravimetrics Era Has Begun – Gravonomy Has Arrived

by Tommy on 15/06/2016

Hmmmmm Bleep. Don’t blink, or you’ll miss it.

Update: Gravinomics – the economics of black holes. Gravology!

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Schrödinger’s Rocket is Dead

by Tommy on 15/06/2016

It’s official, Elon Musk looked inside the box.

Deimos 2 ASDS Barge Smoking Remains

Deimos 2 ASDS Barge Smoking Remains

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Photonic Quantum Geometry and Topology Simulator Created

by Tommy on 13/06/2016


Synthetic Landau levels for photons, Nathan Schine, Albert Ryou, Andrey Gromov, Ariel Sommer and Jonathan Simon, Nature (8 June 2016), doi:10.1038/nature17943

Synthetic photonic materials are an emerging platform for exploring the interface between microscopic quantum dynamics and macroscopic material properties. Photons experiencing a Lorentz force develop handedness, providing opportunities to study quantum Hall physics and topological quantum science. Here we present an experimental realization of a magnetic field for continuum photons. We trap optical photons in a multimode ring resonator to make a two-dimensional gas of massive bosons, and then employ a non-planar geometry to induce an image rotation on each round-trip. This results in photonic Coriolis/Lorentz and centrifugal forces and so realizes the Fock–Darwin Hamiltonian for photons in a magnetic field and harmonic trap. Using spatial- and energy-resolved spectroscopy, we track the resulting photonic eigenstates as radial trapping is reduced, finally observing a photonic Landau level at degeneracy. To circumvent the challenge of trap instability at the centrifugal limit, we constrain the photons to move on a cone. Spectroscopic probes demonstrate flat space (zero curvature) away from the cone tip. At the cone tip, we observe that spatial curvature increases the local density of states, and we measure fractional state number excess consistent with the Wen–Zee theory, providing an experimental test of this theory of electrons in both a magnetic field and curved space. This work opens the door to exploration of the interplay of geometry and topology, and in conjunction with Rydberg electromagnetically induced transparency, enables studies of photonic fractional quantum Hall fluids and direct detection of anyons.

Ok, that was quick. Let the quantum gravity cosmic singularity simulation era begin!

University of Chicago Press Release

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We Live in a Spacetime Quantum Field Theory Pseudogap

by Tommy on 9/06/2016


We are the weirdness in the spacetime pseudogap.

Pandora’s box is open. The cat is out of the bag.

Do you know any other good euphemisms?

I’m afraid I’m fresh out of them.

Pop Goes The Weasel

All around the mulberry bush,
The monkey chased the weasel.
The monkey stopped to pull up his sock,
Pop! goes the weasel.

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CERN LHC Finds Baby Falcon Mascot For SpaceX Elon Musk

by Tommy on 9/06/2016



Photo Credit: Sophia Bennett/CERN

I hope this works out for him.

Her. The CERN chick.

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Simulating Holographic Quantum Gravity With Ultracold Gases

by Tommy on 9/06/2016


Creating and probing the Sachdev-Ye-Kitaev model with ultracold gases: Towards experimental studies of quantum gravity, Ippei Danshita, Masanori Hanada and Masaki Tezuka (8 June 2016)

We suggest that the holographic principle, combined with recent technological advances in atomic, molecular, and optical physics, can lead to experimental studies of quantum gravity. As a specific example, we consider the Sachdev-Ye-Kitaev (SYK) model, which consists of spin-polarized fermions with an all-to-all random two-body hopping and has been conjectured to be dual to a certain quantum gravitational system. We propose that the SYK model can be engineered by confining ultracold fermionic atoms into optical lattices and coupling two atoms with molecular states via photo-association lasers. Achieving low-temperature states of the SYK model is interpreted as a realization of a stringy black hole, provided that the holographic duality is true. We also show how to measure out-of-time-order correlation functions of the SYK model, which allow for identifying the maximally chaotic property of the black hole.

Wasn’t I just talking about this in my cosmic evolution essay? Sure I was. This morning!


I’m glad this is all decided now.

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Space Based Gravitational Wave Detectors Easily Possible

by Tommy on 8/06/2016


Sub-Femto-g Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results, M. Armano et al., Phys. Rev. Lett. 116, 231101 (7 June 2016), doi:10.1103/PhysRevLett.116.231101

We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2 ± 0.1 fm s−2/√Hz, or (0.54 ± 0.01) × 10−15g/√Hz, with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8 ± 0.3) fm/√Hz, about 2 orders of magnitude better than requirements. At f ≤ 0.5  mHz we observe a low-frequency tail that stays below 12 fm s−2/√Hz down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA.

APS Commentary

ESA Press Release

This entire field has wildly exceeded my expectations.

Gravitational manipulation is coming.

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Local Value of Hubble Constant Measured More Precisely

by Tommy on 3/06/2016


A 2.4% Determination of the Local Value of the Hubble Constant, Adam G. Riess, Lucas M. Macri, Samantha L. Hoffmann, Dan Scolnic, Stefano Casertano, Alexei V. Filippenko, Brad E. Tucker, Mark J. Reid, David O. Jones, Jeffrey M. Silverman, Ryan Chornock, Peter Challis, Wenlong Yuan, Peter J. Brown and Ryan J. Foley, Accepted ApJ (17 May 2016)

We use the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) to reduce the uncertainty in the local value of the Hubble constant (H_0) from 3.3% to 2.4%. Improvements come from new, near-infrared observations of Cepheid variables in 11 new hosts of recent SNe~Ia, more than doubling the sample of SNe~Ia having a Cepheid-calibrated distance for a total of 19; these leverage the magnitude-z relation based on 300 SNe~Ia at z < 0.15. All 19 hosts and the megamaser system NGC4258 were observed with WFC3, thus nullifying cross-instrument zeropoint errors. Other improvements include a 33% reduction in the systematic uncertainty in the maser distance to NGC4258, more Cepheids and a more robust distance to the LMC from late-type DEBs, HST observations of Cepheids in M31, and new HST-based trigonometric parallaxes for Milky Way (MW) Cepheids. We consider four geometric distance calibrations of Cepheids: (i) megamasers in NGC4258, (ii) 8 DEBs in the LMC, (iii) 15 MW Cepheids with parallaxes, and (iv) 2 DEBs in M31. H0 from each is 72.02 +/- 2.51, 71.82 +/- 2.67, 75.91 +/- 2.37, and 74.31 +/- 3.27 km/sec/Mpc, respectively. Our best estimate of 73.00 +/- 1.75 km/sec/Mpc combines the anchors NGC4258, MW, and LMC, and includes systematic errors for a final uncertainty of 2.4%. This value is 3.3 sigma higher than 66.93 +/- 0.62 km/sec/Mpc predicted by LambdaCDM with 3 neutrinos with mass 0.06 eV and the Planck data, but reduces to 2.0 sigma relative to the prediction of 69.3 +/- 0.7 km/sec/Mpc with the combination of WMAP + ACT + SPT + BAO, suggesting systematic uncertainties in CMB measurements may play a role in the tension. If we take the conflict between Planck and H0 at face value, one plausible explanation could involve an additional source of dark radiation in the early Universe in the range of Delta Neff = 0.4 – 1. We anticipate significant improvements in H0 from upcoming parallax measurements.

Anybody remember Universe – The Infinite Frontier?

That was probably the best introductory astronomy series ever. I practically earned a BS degree at the St. Petersburg Community college watching that over and over again, endlessly taping it onto extended (six hour) play VHS cassettes on my VCR.

Obviously my preferred hypthesis is a quantum critical Higgs leading to quantum critical black hole collapse, with only the standard model remaining at the electroweak scale, along with a bunch of axions and gravitons of varying mass, hopefully at the eV scale and the low TeV scale.

Gravitational manipulation via bosonic axion fields and axion excitation anyone?

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Earth Water Provided By Carbonaceous Asteroid Bombardment

by Tommy on 1/06/2016


An asteroidal origin for water in the Moon, Jessica J. Barnes, David A. Kring, Romain Tartèse, Ian A. Franchi, Mahesh Anand and Sara S. Russell, Nature Communications, 7, 11684 (31 May 2016), doi:10.1038/ncomms11684

The Apollo-derived tenet of an anhydrous Moon has been contested following measurement of water in several lunar samples that require water to be present in the lunar interior. However, significant uncertainties exist regarding the flux, sources and timing of water delivery to the Moon. Here we address those fundamental issues by constraining the mass of water accreted to the Moon and modelling the relative proportions of asteroidal and cometary sources for water that are consistent with measured isotopic compositions of lunar samples. We determine that a combination of carbonaceous chondrite-type materials were responsible for the majority of water (and nitrogen) delivered to the Earth–Moon system. Crucially, we conclude that comets containing water enriched in deuterium contributed significantly < 20% of the water in the Moon. Therefore, our work places important constraints on the types of objects impacting the Moon ~ 4.5 – 4.3 billion years ago and on the origin of water in the inner Solar System.

I’ll take that drink on the rocks!

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Engineered Van der Waals Multilayer Heterojunction Excitons

by Tommy on 16/05/2016


Near-Unity Absorption in Van der Waals Semiconductors for Ultrathin Photovoltaics, Deep Jariwala, Artur R. Davoyan, Giulia Tagliabue, Michelle C. Sherrott, Joeson Wong and Harry A. Atwater (13 May 2016)

Key criteria for high efficiency photovoltaics include achieving high radiative efficiency, maximizing above-bandgap semiconductor absorption, and enabling carrier-selective charge collection at the cell operating point that exploits the full quasi-Fermi level separation for the carriers. High efficiency inorganic photovoltaic materials (e.g., Si, GaAs and GaInP) can achieve these criteria, but thin film photovoltaic absorbers have lacked the ability to fulfill one or more of these criteria, often due to surface and interface recombination effects. In contrast, Van der Waals semiconductors have naturally passivated surfaces with electronically active edges that allows retention of high electronic quality down-to the atomically thin limit and recent reports suggest that Van der Waals semiconductors can achieve the first criterion of high radiative efficiency. Here, we report that the second criteria for high efficiency of near-unity light absorption is possible in extremely thin (< 15 nm) Van der Waals semiconductor structures by coupling to strongly damped optical modes of semiconductor/metal heterostructures. We demonstrate near unity, broadband absorbing photovoltaic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) as van der Waals semiconductor active layers. Our TMDC devices show a short circuit current density > 10 mA/cm2 at ~ 20 Suns and exhibits spectral response that parallels the spectral absorption over the above bandgap region. Our work addresses one of the key criteria to enable TMDCs to achieve high photovoltaic efficiency.

See also: http://arxiv.org/abs/1605.04255

Engineering and Manipulating Structured Excitons, Xiaoning Zang, Simone Montangero, Lincoln D. Carr and Mark T. Lusk (13 May 2016)

When a semiconductor absorbs light, the resulting electron-hole superposition amounts to a uncontrolled quantum ripple that eventually degenerates into diffusion (Frenkel 1931, Wannier 1937, Lanzani 2012). If the conformation of these excitonic superpositions could be engineered, though, they would constitute a new means of transporting information and energy. We show that properly designed laser pulses can be used to create such structured excitons. They can be formed with a prescribed speed, direction and spectral make-up that allows them to be selectively passed, rejected or even dissociated using superlattices. Their coherence also provides a handle for manipulation using active, external controls. Energy and information can be conveniently processed and subsequently removed at a distant site by reversing the original procedure to produce a stimulated emission. The ability to create, manage and remove structured excitons comprises the foundation for opto-excitonic circuits with application to a wide range of quantum information, energy and light-flow technologies. The paradigm is demonstrated using both tight-binding and Time-Domain Density Functional Theory simulations.

I don’t quite understand what the hold up with this could be.

Commercial capital, or government funding?

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Superconductors as (Very) Light Axion Dark Matter Absorbers

by Tommy on 16/05/2016


Detecting Ultralight Bosonic Dark Matter via Absorption in Superconductors, Yonit Hochberg, Tongyan Lin and Kathryn M. Zurek (22 April 2016)

Superconducting targets have recently been proposed for the direct detection of dark matter as light as a keV, via elastic scattering off conduction electrons in Cooper pairs. Detecting such light dark matter requires sensitivity to energies as small as the superconducting gap of O(meV). Here we show that these same superconducting devices can detect much lighter DM, of meV to eV mass, via dark matter absorption on a conduction electron, followed by emission of an athermal phonon. We demonstrate the power of this setup for relic kinetically mixed hidden photons, pseudoscalars, and scalars, showing the reach can exceed current astrophysical and terrestrial constraints with only a moderate exposure.

See also: http://arxiv.org/abs/1504.07237

Superconducting Detectors for Super Light Dark Matter, Yonit Hochberg, Yue Zhao and Kathryn M. Zurek, Phys. Rev. Lett. 116, 011301 (7 January 2016), doi:10.1103/PhysRevLett.116.011301

We propose and study a new class of superconducting detectors which are sensitive to O(meV) electron recoils from dark matter-electron scattering. Such devices could detect dark matter as light as the warm dark matter limit, mX > keV. We compute the rate of dark matter scattering off of free electrons in a (superconducting) metal, including the relevant Pauli blocking factors. We demonstrate that classes of dark matter consistent with terrestrial and cosmological/astrophysical constraints could be detected by such detectors with a moderate size exposure.

With topological superconductors I can detect fluctuating dynamical axion fields as well.

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Sulfur Isotopes Date Great Atmospheric Oxygen Inversion Event

by Tommy on 14/05/2016


Rapid oxygenation of Earth’s atmosphere 2.33 billion years ago, Genming Luo, Shuhei Ono, Nicolas J. Beukes, David T. Wang, Shucheng Xie and Roger E. Summons, Science Advances 2, 5, e1600134 (6 May 2016), doi:10.1126/sciadv.1600134

Molecular oxygen (O2) is, and has been, a primary driver of biological evolution and shapes the contemporary landscape of Earth’s biogeochemical cycles. Although “whiffs” of oxygen have been documented in the Archean atmosphere, substantial O2 did not accumulate irreversibly until the Early Paleoproterozoic, during what has been termed the Great Oxygenation Event (GOE). The timing of the GOE and the rate at which this oxygenation took place have been poorly constrained until now. We report the transition (that is, from being mass-independent to becoming mass-dependent) in multiple sulfur isotope signals of diagenetic pyrite in a continuous sedimentary sequence in three coeval drill cores in the Transvaal Supergroup, South Africa. These data precisely constrain the GOE to 2.33 billion years ago. The new data suggest that the oxygenation occurred rapidly—within 1 to 10 million years—and was followed by a slower rise in the ocean sulfate inventory. Our data indicate that a climate perturbation predated the GOE, whereas the relationships among GOE, “Snowball Earth” glaciation, and biogeochemical cycling will require further stratigraphic correlation supported with precise chronologies and paleolatitude reconstructions.

It’s quite possible the oxygen was there all along in the upper atmosphere and the climate perturbation initiated a great atmospheric oxygen inversion layer collapse to the surface, resulting in geologically instantaneous oxygenation. That’s my crackpot theory at this point.

This will take a while to sort out.

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Early Earth Achaean Atmosphere Was Chemically Differentiated

by Tommy on 12/05/2016


Ancient micrometeorites suggestive of an oxygen-rich Archaean upper atmosphere, Andrew G. Tomkins, Lara Bowlt, Matthew Genge, Siobhan A. Wilson, Helen E. A. Brand and Jeremy L. Wykes, Nature, 533, 235–238 (11 May 2016), doi:10.1038/nature17678

It is widely accepted that Earth’s early atmosphere contained less than 0.001 per cent of the present-day atmospheric oxygen (O2) level, until the Great Oxidation Event resulted in a major rise in O2 concentration about 2.4 billion years ago. There are multiple lines of evidence for low O2 concentrations on early Earth, but all previous observations relate to the composition of the lower atmosphere in the Archaean era; to date no method has been developed to sample the Archaean upper atmosphere. We have extracted fossil micrometeorites from limestone sedimentary rock that had accumulated slowly 2.7 billion years ago before being preserved in Australia’s Pilbara region. We propose that these micrometeorites formed when sand-sized particles entered Earth’s atmosphere and melted at altitudes of about 75 to 90 kilometres (given an atmospheric density similar to that of today). Here we show that the FeNi metal in the resulting cosmic spherules was oxidized while molten, and quench-crystallized to form spheres of interlocking dendritic crystals primarily of magnetite (Fe3O4), with wüstite (FeO)+metal preserved in a few particles. Our model of atmospheric micrometeorite oxidation suggests that Archaean upper-atmosphere oxygen concentrations may have been close to those of the present-day Earth, and that the ratio of oxygen to carbon monoxide was sufficiently high to prevent noticeable inhibition of oxidation by carbon monoxide. The anomalous sulfur isotope (Δ33S) signature of pyrite (FeS2) in seafloor sediments from this period, which requires an anoxic surface environment, implies that there may have been minimal mixing between the upper and lower atmosphere during the Archaean.

I suppose this would be the greenhouse gas and oxygen companion to the previous article.

They told me when I was a young child that I would not start to know the answers to some of these questions before the second decade of the next century, and I now remember how disappointed I was that there would be no flat screen TVs and Dick Tracy watches any time soon. But here it is already now, the 2nd decade of the 21st century, and they were right!

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This is Your Only Planet Earth on Carbon Dioxide Steroids

by Tommy on 12/05/2016
Planet Earth Average Global Surface Temperature Anomaly

Planet Earth Average Global Surface Temperature Anomaly

Fort McMurray citizens can now get back to their important task of profiting from destruction.

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Monolayer Arsenene and Antimonene Allotropes Studied

by Tommy on 10/05/2016


First-principle calculations of phononic, electronic and optical properties of monolayer arsenene and antimonene allotropes, Yuanfeng Xu, Bo Peng, Hao Zhang, Hezhu Shao, Rongjun Zhang, Hongliang Lu, David Wei Zhang and Heyuan Zhu (12 April 2016)

Recently a stable monolayer of antimony in buckled honeycomb structure called antimonene was successfully grown on 3D topological insulator Bi2Te3 and Sb2Te3, which displays semiconducting properties. By first principle calculations, we systematically investigate the phononic, electronic and optical properties of α− and β− allotropes of monolayer arsenene/antimonene. We investigate the dynamical stabilities of these four materials by considering the phonon dispersions. The obtained electronic structures reveal the direct band gap of monolayer α−As/Sb and indirect band gap of β−As/Sb. Significant absorption is observed in α−Sb, which can be used as a broad saturable absorber.

See also: http://pubs.acs.org/doi/abs/10.1021/acsami.5b02441

Atomically Thin Group V Elemental Films: Theoretical Investigations of Antimonene Allotropes, Gaoxue Wang, Ravindra Pandey and Shashi P. Karna, ACS Appl. Mater. Interfaces, 2015, 7 (21), pp 11490–11496 (8 May, 2015), DOI:10.1021/acsami.5b02441

Group V elemental monolayers including phosphorene are emerging as promising 2D materials with semiconducting electronic properties. Here, we present the results of first-principles calculations on stability, mechanical and electronic properties of 2D antimony (Sb), antimonene. Our calculations show that free-standing α and β allotropes of antimonene are stable and semiconducting. The α-Sb has a puckered structure with two atomic sublayers and β-Sb has a buckled hexagonal lattice. The calculated Raman spectra and STM images have distinct features thus facilitating characterization of both allotropes. The β-Sb has nearly isotropic mechanical properties, whereas α-Sb shows strongly anisotropic characteristics. An indirect–direct band gap transition is expected with moderate tensile strains applied to the monolayers, which opens up the possibility of their applications in optoelectronics.

I’m not quite sure if I covered this earlier or not.

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