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This Stellar Fusion Game is Shockingly Addictive

This Stellar Fusion Game is Shockingly Addictive | Physics | Scoop.it
Stars are colossal fusion reactors, burning hydrogen into helium. As the nuclei fuse lighter elements into heavier elements, massive amounts of energy are released. A new game sets you the task of nucleosynthesis, building hydrogen into iron, and it's surprisingly fun.
Mikko Hakala's insight:

Now here is a review of a game where you get to control nucleosynthesis. Nice way to learn about fusion in stars.

 

The game: http://newbrict.github.io/Fe26/

 

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Scientists capture ultrafast snapshots of light-driven superconductivity

Scientists capture ultrafast snapshots of light-driven superconductivity | Physics | Scoop.it
A new study pins down a major factor behind the appearance of superconductivity—the ability to conduct electricity with 100 percent efficiency—in a promising copper-oxide material.
Mikko Hakala's insight:

X-ray studies bring insight into developing room-temperature superconductors. This laser pump - x-ray probe experiment showed that the appearance of superconductivity is not related to lattice distortions (the distortions persist longer than the melting of charge stripes, i.e. the point where superconductivity emerges).

 

The findings are relevant for understanding generally the mechanism of superconductivity in layered copper oxide materials, and in the new field of light-induced superconductivity.

 

The experimental x-ray method used was resonant soft x-ray diffraction.

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Finnish inventor rethinks design of the axe

Finnish inventor rethinks design of the axe | Physics | Scoop.it
(Phys.org) —Finnish inventor Heikki Kärnä is the man behind the Vipukirves Leveraxe, which is a precision tool for splitting firewood. He designed the tool to make the job easier and more efficient, with no need for an external source of energy. In short, he has redesigned the axe. This is a lever-based ...
Mikko Hakala's insight:

Clever physics-based improvements for manual wood splitting. Great example of creativity!

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Scientists observe quantum superconductor-metal transition and superconducting glass

Scientists observe quantum superconductor-metal transition and superconducting glass | Physics | Scoop.it
An article published in Nature Physics on March 30, 2014, presents the results of the first experimental study of graphene-based quantum phase transition of the 'superconductor-to-metal' type, i.e.
Mikko Hakala's insight:
Interesting developments in this field. Voltage-controlled quantum phase transition (exponential dependence).
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World-record current in a superconductor | CERN

World-record current in a superconductor | CERN | Physics | Scoop.it
In the framework of the High-Luminosity LHC project, experts from the CERN Superconductors team recently obtained a world-record current of 20 kA at 24 K in an electrical transmission line consisting of two 20-metre long cables made of magnesium diboride (MgB2) superconductor. This result makes the technology a viable solution for long-distance power transportation.
Mikko Hakala's insight:

Interesting, world record current with MgB2 superconducting wires achieved. Proposals to use for long-distance transport transmission lines for electrical power. Developments were also needed for high-current cables.  

 

Superconductivity of MgB2 was discovered only in 2001.

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Density functional theory - Wikipedia, the free encyclopedia

Density functional theory - Wikipedia, the free encyclopedia

Despite recent improvements, there are still difficulties in using density functional theory to properly describe intermolecular interactions, especially van der Waals forces (dispersion); charge transfer excitations; transition states, global potential energy surfaces, dopant interactions and some other strongly correlated systems; and in calculations of the band gap and ferromagnetism in semiconductors.

Recent perspectives in The Journal of Chemical Physics:

 

http://scitation.aip.org/content/aip/journal/jcp/140/18/10.1063/1.4869598

 

http://scitation.aip.org/content/aip/journal/jcp/136/15/10.1063/1.4704546

 

http://scitation.aip.org/content/aip/journal/jcp/137/12/10.1063/1.4754130

 

Mikko Hakala's insight:

Here are three useful perspectives on density functional theory worth knowing about. Published in The Journal of Chemical Physics.

 

1) By Axel Becke (2014): "Fifty years of density-functional theory in chemical physics"

http://scitation.aip.org/content/aip/journal/jcp/140/18/10.1063/1.4869598

- "outlines the history, basic concepts, and present status of KS-DFT in chemical physics, and offers suggestions for its future development"

- emphasis on "occupied orbitals only", ground state approaches

 

2) By Kieron Burke (2012): "Perspective on density functional theory"

http://scitation.aip.org/content/aip/journal/jcp/136/15/10.1063/1.4704546

- "reviews some recent progress and ongoing challenges"

- selected topics for general audience

 

3) By Klimes and Michaelides (2012): "Advances and challenges in treating van der Waals dispersion forces in density functional theory"

http://scitation.aip.org/content/aip/journal/jcp/137/12/10.1063/1.4754130

- discussion of promising recent schemes for including dispersion

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First principles approach to creating new materials

First principles approach to creating new materials | Physics | Scoop.it
Traditionally, scientists discover new materials, and then probe them to try to better understand their properties. Theoretical materials physicist Craig Fennie does it in reverse.
Mikko Hakala's insight:

A fairly good article on aspects in the so-called 'first principles' materials design. Design from first principles means computational prediction of the properties of new materials (e.g. their structural, electrical, optical, magnetic properties), assuming a certain level for the theoretical description. The aim is to achieve a desired structure-property relation. The critical point is if such theoretical structures can be synthesized in reality. If yes, characterization shows if they actually exhibits the desired property.

 

See also the figure captions for additional useful information.

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Quantum photon properties revealed in another particle—the plasmon

Quantum photon properties revealed in another particle—the plasmon | Physics | Scoop.it
(Phys.org) —For years, researchers have been interested in developing quantum computers—the theoretical next generation of technology that will outperform conventional computers. Instead of holding data in bits, the digital units used by computers today, quantum computers store information in units ...
Mikko Hakala's insight:

Quantum interference between surface plasmons demonstrated. Two indistinguishable photons converted into two indistinguishable plasmons in the waveguides.   

 

Original article: http://www.nature.com/nphoton/journal/v8/n4/abs/nphoton.2014.40.html

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The Elements Revealed: An Interactive Periodic Table

The Elements Revealed: An Interactive Periodic Table | Physics | Scoop.it
Whether gas, liquid or solid; radioactive or stable; reactive or inert; toxic or in your vitamin pill, the 118 building blocks each has its own chemically idiosyncratic characteristics--and certain commonalities. See what makes your favorite element unique on this interactive periodic table
Mikko Hakala's insight:

Interactive periodic table by Scientific American. The following info is available for each element:

1) Fun fact - quick useful info of the element in a couple of sentences, 2) Phase, 3) Category, 4) Atomic weight, 5) Link to a Nature Chemistry article (for some of the elements)

The fun facts are nicely informative.

 

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Physicists on Twitter

Physicists on Twitter | Physics | Scoop.it
List of physicists who have over 1,000 Twitter followers. Tweet additions and comments to @Lucretius21c. This list is available in the Twitter list system. For popular recent tweets of those listed...
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The list gives bio, number of followers and tweet rate.

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Scientists track 3-D nanoscale changes in rechargeable battery material during operation

Scientists track 3-D nanoscale changes in rechargeable battery material during operation | Physics | Scoop.it

Scientists at the U.S. Department of Energy's Brookhaven National Laboratory have made the first 3D observations of how the structure of a lithium-ion battery anode evolves at the nanoscale in a real battery cell as it discharges and recharges.


Via José Gonçalves
Mikko Hakala's insight:

What happens in the real battery's anode material during the initial charge/discharge cycles? For the first time structural evolution could be observed by in situ at nanoscale resolution (~30 nm) in 3D. 

 

Measurements with transmission x-ray microscope at Brookhaven National Synchrotron Light Source.

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Neutron Reactions in Astrophysics

Neutron Reactions in Astrophysics | Physics | Scoop.it

Via tmertzi
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Review of how elements in the mass region above iron are formed in nucleosynthesis. In this region the formation is dominated by neutron capture.

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tmertzi's curator insight, March 25, 3:19 PM

A must read for all people involved in Nuclear Astro

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Japan, Belgium and Italy reduce their stockpiles of nuclear material

Japan, Belgium and Italy reduce their stockpiles of nuclear material | Physics | Scoop.it
Announcements made during US-led summit in The Hague aimed at reducing the threat of nuclear terrorism
Mikko Hakala's insight:

 

Nuclear security summit in The Hague. See

https://www.nss2014.com/en/news/outcome-of-nss-2014-a-major-step-towards-a-safer-world

 

Agreements on

- how to reduce dangerous nuclear materials (highly enriched uranium, plutonium)

- improve security of radioactive material (low enriched U, Co-60, Sr-90, Cs-137) that could used for a 'dirty bomb'

- improve international information exchange and cooperation

 

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Solar-cell materials and efficiencies

Solar-cell materials and efficiencies | Physics | Scoop.it

What are the types and efficiencies of current phovoltaic materials? This Wikimedia Commons graph is a great, constantly updated reference to various photovoltaic technologies under research. The classification is to following types of cells:

 

1) multijunction

2) single-junction GaAs

3) crystalline Si

4) thin-film (CIGS, CdTe, amorphous and other forms of Si )

5) emerging (perovskite, quantum dot, organic, inorganic, dye-sensitized)

Follow it to stay updated on recent achievements.

 

More information:

 

* Nature Photonics has a focus issue on a set of cutting-edge solar cell technologies. It covers quantum dot, polymer, dye-sensitized and intermediate-band solar cells: http://www.nature.com/nphoton/focus/photovoltaics/index.html

The editorial 'A sunny outlook': http://www.nature.com/nphoton/journal/v6/n3/full/nphoton.2012.38.html

 * Brief info on CdTe: http://spectrum.ieee.org/nanoclast/green-tech/solar/what-makes-for-better-cdte-solar-cells  Figure: By NREL (US Department of Energy) [Public domain], via Wikimedia Commons

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Impurity size affects performance of emerging superconductive material

Impurity size affects performance of emerging superconductive material | Physics | Scoop.it
Research from North Carolina State University finds that impurities can hurt performance – or possibly provide benefits – in a key superconductive material that is expected to find use in a host of applications, including future particle colliders.
Mikko Hakala's insight:
Role of defects in the high critical temperature superconductor material bismuth strontium calsium copper oxide Bi2212 discussed. This is a promising material for superconducting wires. Small-sized defects act as beneficial pinning centers for the magnetic vortices, thus preventing resistance build up when magnetic fields are present.
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Throwback Thursday: Top 5 Signs of New Physics

Throwback Thursday: Top 5 Signs of New Physics | Physics | Scoop.it
The Standard Model can’t be all there is. Here are five compelling reasons why.
Mikko Hakala's insight:

What lies beyond the Standard Model? If you want to get a nice summary of the current state of the art, read this quality article. From dark matter to baryogenesis, the article discusses 5 exciting clues.

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Top 10 Things You Didn't Know About Brookhaven National Laboratory

Top 10 Things You Didn't Know About Brookhaven National Laboratory | Physics | Scoop.it
Top 10 Things You Didn't Know About Brookhaven National Laboratory
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From Maglev via one of the first video games and insulin to Higgs. Interesting information.

 

Others articles in this series: http://energy.gov/joules-wisdom-top-things-you-didnt-know-about-energy

 

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Chris Gozzard - YouTube

Chris Gozzard - YouTube | Physics | Scoop.it
I teach A level and IGCSE Physics (and a little Chemistry).. I have made this revision channel for my students but anyone is welcome to ask for guidance and ...
Mikko Hakala's insight:

A lot of short physics lessons in YouTube by Chris Gozzard. Can be used for flipped classroom.

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Controlling a Molecule’s Fate

Controlling a Molecule’s Fate | Physics | Scoop.it
By selecting the intensity and duration of an ultrashort laser pulse, researchers are able to control the breakup of a molecule through the relation between its electrons and nuclei.
Mikko Hakala's insight:

Viewpoint on how ultrashort laser pulses can be used to control and steer the dissociation dynamics of small molecules (via various fragmentation pathways).

 

The article gives a brief, informative overview of the basic physics and phenomena involved in photodissociation. In particular, different fragmentation outcomes for ethylene are discussed, depending on from which valence orbitals electrons are removed by the laser field.

 

The main Phys. Rev. X article is fully open access: http://dx.doi.org/10.1103/PhysRevX.4.021005

 

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[1404.1854] The Statistical Physics of Athermal Materials

Abstract:

At the core of equilibrium statistical mechanics lies the notion of statistical ensembles: a collection of microstates, each occurring with a given a priori probability that depends only on a few macroscopic parameters such as temperature, pressure, volume, and energy. In this review article, we discuss recent advances in establishing statistical ensembles for athermal materials. The broad class of granular and particulate materials is immune from the effects of thermal fluctuations because the constituents are macroscopic. In addition, interactions between grains are frictional and dissipative, which invalidates the fundamental postulates of equilibrium statistical mechanics. However, granular materials exhibit distributions of microscopic quantities that are reproducible and often depend on only a few macroscopic parameters. We explore the history of statistical ensemble ideas in the context of granular materials, clarify the nature of such ensembles and their foundational principles, highlight advances in testing key ideas, and discuss applications of ensembles to analyze the collective behavior of granular materials.

Mikko Hakala's insight:

Review on statistical physics of athermal condensed matter (granular, paticulate materials).

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Concepts for teaching superconductors

Concepts for teaching superconductors | Physics | Scoop.it

"Concepts of superconductors for teaching purposes in a solid-state physics course."

 

Free to use under Creative Commons licensing.

Mikko Hakala's insight:

Here's my visual plan to teach superconductors in an ongoing course. Free to use under Creative Commons licensing.

 

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Jacobs Physics

Jacobs Physics | Physics | Scoop.it

"Resources for teachers and students of introductory physics"

Mikko Hakala's insight:

Lots of good, practical physics content and interesting teaching discussions in this blog.

 

See for example this post about how much the teacher should be talking in front of the class:

http://jacobsphysics.blogspot.fi/2014/01/is-there-any-point-at-all-in-talking-in.html

 

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Scientists open a new window into quantum physics with superconductivity in LEDs

Scientists open a new window into quantum physics with superconductivity in LEDs | Physics | Scoop.it
A team of University of Toronto physicists led by Alex Hayat has proposed a novel and efficient way to leverage the strange quantum physics phenomenon known as entanglement.

Via Jocelyn Stoller
Mikko Hakala's insight:

Put a superconductor in contact with a semiconductor LED. According to the article, when Cooper pairs are injected into LED the emitted photons are entangled. Interesting opening.

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France supports the European XFEL | e-EPS

France supports the European XFEL | e-EPS | Physics | Scoop.it
With a contribution of 36 million € toward the construction, France has joined the European XFEL as a shareholder country.

Via tmertzi
Mikko Hakala's insight:

Good news. Here are research possibilities what European X-ray Free Electron Laser can do:http://www.xfel.eu/research/possibilities/


Basic info on European XFEL:

http://en.wikipedia.org/wiki/European_x-ray_free_electron_laser

 

 

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tmertzi's curator insight, March 27, 6:22 AM

A critical step for financing a major machine in Europe

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Physics Simulation Applets

Physics simulation applets - Fysiikan simulaatio-appletit

- Phonon dispersion in a linear chain - fononidispersio lineaarisessa ketjussa

- Ideal gas processes - ideaalikaasuprosesseja

- Vibrating chain - värähtelevä ketju

- Vibrating plane - värähtelevä taso

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Mikko Hakala's comment, March 26, 1:39 PM
Physics applets by @thynnine