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Fundamentals of physics confirmed: Experiments testing Einstein's time dilation and quantum electrodynamics

Fundamentals of physics confirmed: Experiments testing Einstein's time dilation and quantum electrodynamics | Physics | Scoop.it
The special theory of relativity of Albert Einstein and quantum electrodynamics, which was formulated by, among others, Richard Feynman, are two important fundaments of modern physics. In cooperation with colleagues from several international universities and institutes, the research group of Professor ...
Mikko Hakala's insight:

 

Detecting fluorescence radiation from relativistically moving ions is here used to test two fundamental physics theories: special relativity and QED.  - Better precision obtained in the experiments, no violations found.

 

http://phys.org/news/2014-10-fundamentals-physics-einstein-dilation-quantum.html

 

Direct links to the studies:

 

Special relativity

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.120405

http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.113.120405 ;

 

Hyperfine splitting (predicted by quantum electrodynamics)

http://journals.aps.org/pra/abstract/10.1103/PhysRevA.90.030501

 

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Making Invisible Cracks Visible

Making Invisible Cracks Visible | Physics | Scoop.it
A new acoustic imaging technique could reveal previously invisible cracks in bridges or other infrastructure.
Mikko Hakala's insight:

A new nonlinear ultrasonic acoustic imaging technique is developed for detecting cracks in materials (due to e.g. fatigue).

 

The technique is simple and practical because it uses standard imaging equipment and is based on established linear methods.

 

http://physics.aps.org/articles/v7/100

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.144301

 

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LHC research, presented in tangible tidbits

LHC research, presented in tangible tidbits | Physics | Scoop.it
Students working on their PhDs at the Large Hadron Collider explain their research with snacks, board games and Legos.
Mikko Hakala's insight:

Matter, fundamental particles and standard model - A three minute visual explanation with legos.

 

PhD student Eric Takasugi explains his studies at CERN.

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Acid Ions are More Than Spectators

Acid Ions are More Than Spectators | Physics | Scoop.it

"X-ray absorption fine structure (EXAFS) measurements carried out at the U.S. Department of Energy's (DOE's) Advanced Photon Source, coupled with state-of-the-art density functional theory (DFT) simulations reveal that strong acids, such as hydrochloric acid, form counter-ion pairs in solution across all concentration, a result that had not been seen in gas-phase studies. The discovery suggests that it is not simply the release of protons — hydrogen ions — that is important for the properties of acids."

Mikko Hakala's insight:

Structure of complex liquids - Case of aqueous hydrochloric acid

 

X-ray spectroscopy study from Argonne and Pacific Northwest National Laboratories sheds new light on the microscopic structure of aqueous hydrocholric acid (HCl). The study reports persistent pairing of the counterion (Cl-) and the hydronium ion (H3O+).

 

Previously, Cl- has been thought to be more like a separately solvated 'spectator', after dissociation of HCl. Thus the study shows the dissociation is not ideal. These contact-ion pairs seem to more important than expected for the properties of the solution. 

 

Interested in more news related to modern X-ray physics and spectroscopy? Follow @helixsfi (recently launched). 

 

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Magnets for fusion energy: A revolutionary manufacturing method developed

Magnets for fusion energy: A revolutionary manufacturing method developed | Physics | Scoop.it
The National Institute for Fusion Science (NIFS), of the National Institutes of Natural Sciences (NINS) in Japan, has achieved an electrical current of 100,000 amperes, which is by far the highest in the world, by using the new idea of assembling...

Via tmertzi
Mikko Hakala's insight:

World-record electrical current demonstrated, 100 000 A, obtained with stacked yttrium-based superconducting tapes. Superconductors are the only viable option, since they can carry large dissipationless electrical currents.

 

As electrical current creates a magnetic field, superconductors can be used to create strong magnets. These in turn are needed in fusion reactors to control the plasma, in medical instruments and in power-electronics devices.

 

A short article explaining the achievement and two good illustrations. 

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Perovskite Solar Cell Technology of Oxford PV, The Potential Game-Changer | Sun Is The Future

Perovskite Solar Cell Technology of Oxford PV, The Potential Game-Changer | Sun Is The Future | Physics | Scoop.it
Dear Friends, Visitors/Viewers/Readers, (Please click on red links and note magenta) At InterSolar North America 2014 in San Francisco, CA, I came across
Mikko Hakala's insight:

 

Solar cell technology based on perovskites

 

Useful info in the post and interview on Oxford PV activities in this field. In the video Dr. Christopher Case describes the material and its applications in various ways in solar cell technologies. Here's my quick summary of the video's content:

 

0:45 Fastest increasing photovoltaic efficiency 

1:15 Thin film material

1:35 Applications, initial view of the company was to develop semi-transparent coatings

2:10 Can be made in almost any color

3:00 New application of perovskites: tandem solar cells (perovskite coating on conventional Si)

4:10 What are perovskites

4:45 How to tailor the properties

5:10 Material itself studied already for decades

5:50 Finding the planar form by Prof. Snaith was a breakthrough

6:40 More and more papers coming out on this material

6:55 Perovskite on Si solar cells boosts efficiency, easier to make this product than a fully integrated PV

7:40 Perovskites fundamentally and perspectives for efficiency

8:15 Potential to replace Si?

8:40 About processing: it's solution processed from inexpensive materials

9:30 Future steps. Towards full perovskite-on-perovskite tandem cells

9:50 How to get in contact, what their company's website contains

 

 

 

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Surrey NanoSystems has "super black" material

Surrey NanoSystems has "super black" material | Physics | Scoop.it
(Phys.org) —A British company says it has scored a breakthrough in the world's darkest material. Surrey NanoSystems describes its development as not just a black material but super-black. They are calling it Vantablack, and they are singling out its ability to be applied to lightweight, temperature-sensitive ...
Mikko Hakala's insight:

Here is the ultimate black. This coating material is made from carbon nanotubes, with promising applications for example for telescopes.

 

There are also nice physics discussions in the comments.

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Supercomputers reveal strange, stress-induced transformations in world's thinnest materials

Supercomputers reveal strange, stress-induced transformations in world's thinnest materials | Physics | Scoop.it
(Phys.org) —Interested in an ultra-fast, unbreakable, and flexible smart phone that recharges in a matter of seconds? Monolayer materials may make it possible. These atom-thin sheets—including the famed super material graphene—feature exceptional and untapped mechanical and electronic properties. ...
Mikko Hakala's insight:

Behavior under stress of 4 novel monolayer materials studied (graphene, graphane, BN, MOS2), by density functional theory calculations.

 

By these simulations researchers identified a common soft (vibrational) mode failure mechanism that leads to the eventual breaking of these 2D-materials under stress. 

 

The article has a useful 'Key Takeaways' section in the end.

 

 

 

 

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Upgrade for European light source

Upgrade for European light source | Physics | Scoop.it

European Synchrotron Radiation Facility (ESRF). One of Europe's premier scientific research laboratories is to go through a major upgrade.


Via tmertzi
Mikko Hakala's insight:

 

European Synchrotron Radiation Facility (ESRF) is a most powerful X-ray machine in Europe, supported and shared by 20 countries. See http://www.esrf.eu/ ;

 

ESRF is going through a major upgrade. This BBC article by @BBCAmos (via @tmertzi) tells some essential information what this means to ESRF. See how much more radiation will be obtained, how much will the upgrade cost and the timetables.

 

How synchrotron X-rays are generated and how research is done with them? Here is one recent video from a canadian synchrotron explaining basic operation:

http://globalnews.ca/video/1439365/synchrotron-matters

(via @CanLightSource, @lightsources)

 

Follow ESRF in Twitter: @esrfsynchrotron

 

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▶ How Chemistry Creates Really Big Bubbles | Outrageous Acts of Science - YouTube

Everyone loves bubbles... but you've never seen them quite like this. Great video for introducing surface tension.


Via Andrew van Zyl
Mikko Hakala's insight:

What keeps the bubble from bursting? Learn about

 

* the role of surface tension

* how to lower it

* how to avoid water evaporation

 

2 minute video.

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Shatterproof screens that save smartphones

Shatterproof screens that save smartphones | Physics | Scoop.it
University of Akron polymer scientists have developed a transparent electrode that could change the face of smartphones, literally, by making their displays shatterproof.
Mikko Hakala's insight:

Current touch displays are capacitive and they need transparent conducting layers as part of the structure. ITO (indium tin oxide) glass is the most often used technology for these layers. However, it is costly and brittle, so alternatives are sought. 

 

This article presents a metal-nanowire based alternative film, which has better properties than ITO (better conductivity and flexibility). There are also other alternatives, for example based on carbon nanotubes or polymers. These kind of findings are potentially important since there seems to be big a market to replace ITO.

 

An excellent explanation (5 pages) of the technology of touch screens can be found here: http://www.computerworld.com/s/article/9231961/How_it_works_The_technology_of_touch_screens

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Team first to detect exciton in metal

Team first to detect exciton in metal | Physics | Scoop.it
University of Pittsburgh researchers have become the first to detect a fundamental particle of light-matter interaction in metals, the exciton. The team will publish its work online June 1 in Nature Physics.
Mikko Hakala's insight:

Observation of excitons in metals is difficult due to their short lifetimes. This research reports detection on metal surfaces via multiphoton photoemission.

 

Quick info on excitons: http://en.wikipedia.org/wiki/Exciton

 

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Design and synthesis of the first triply twisted Möbius annulene : Nature Chemistry : Nature Publishing Group

Design and synthesis of the first triply twisted Möbius annulene : Nature Chemistry : Nature Publishing Group | Physics | Scoop.it
Most cyclic conjugated molecules, such as benzene, exhibit two sides. Möbius annulenes, however, with an odd number of 180° twists in their π system are one-sided and violate the Hückel rule. Now, using a topological trick it is demonstrated that triply twisted systems are not particularly strained and probably easier to synthesize than singly twisted ones.
Mikko Hakala's insight:

Topology and chemistry combined: Annulene in a Möbius ring configuration with three twists. Applications could be found in optoelectronics and nanotechnology.

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The Nobel Prize in Physics 2014

The Nobel Prize in Physics 2014 | Physics | Scoop.it

The Nobel Prize in Physics 2014 was awarded jointly to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources".

Mikko Hakala's insight:

The Nobel prize website offers both the popular and the more detailed scientific background of blue LEDs.

 

Quoting from the latter: "GaN-based LEDs result from a long series of breakthroughs in basic materials physics and crystal growth, in device physics with advanced heterostructure design, and in optical physics for the optimization of the light out-coupling."

 

The effort was worth it. The luminosity [measured in lumens] / power [measured in watts] increases roughly as follows (from the popular article):

   Light bulb, 1x 

   Fluorescent lamp, 4x 

   LED lamp, 19x

So roughly 20 times less energy consumed compared to light bulbs.

 

More detailed scientific background for blue LEDs:

http://www.nobelprize.org/nobel_prizes/physics/laureates/2014/advanced-physicsprize2014.pdf

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Team pioneers strategy for creating new materials

Team pioneers strategy for creating new materials | Physics | Scoop.it
Making something new is never easy. Scientists constantly theorize about new materials, but when the material is manufactured it doesn't always work as expected. To create a new strategy for designing materials, scientists at the Department of Energy's Argonne National Laboratory combined two different ...
Mikko Hakala's insight:

Processing (MBE), characterization (X-ray scattering) and computations (DFT) are combined here for better growth strategies in making new materials.

 

Molecular beam epitaxy (MBE) is used to make the layered structures, which are characterized with in situ synchrotron X-ray scattering measurements. Computations with density functional theory (DFT) level are performed to understand the resulting structures.

 

Ability to grow such new oxide materials in a controlled way is important, since the materials can be tuned to have various ferroelectric, catalytic, magnetic and dielectric properties. Tuning these properties is important for applications.

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The Smallest Possible Scale in the Universe

The Smallest Possible Scale in the Universe | Physics | Scoop.it
Is there a limit to how small a length can be?
Mikko Hakala's insight:

Sabine Hossenfelder (@skdh) writes about the possible existence of the smallest length in the universe, the fundamental smallest possible difference in position.  

 

This is the Planck length: 10^30 times smaller than the diameter of the blood cell, or 10^20 times smaller than the nucleus.

  

Does such a fundamental limit exist? And if yes, what are the consequences? Or in other words, is there a limit how sharp the resolution can be?

 

Read more about this fundamental and open question:

https://medium.com/starts-with-a-bang/the-smallest-possible-scale-in-the-universe-9e79497b9945

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Microwaving Light Bulbs Is Genuinely Useful (And Entertaining)

Microwaving Light Bulbs Is Genuinely Useful (And Entertaining) | Physics | Scoop.it
I love finding new things to put in the microwave. Say, for instance, an incandescent light bulb, which can test your microwave for a number of issues, besides just looking awesome. Even a non-functioning bulb can work, so dig out the dusty old bulbs you have at the back of the closet.
Mikko Hakala's insight:

Things to learn from light bulbs and the microwave oven: interference, electromagnetic induction, leakage flux. - Physics demonstration with everyday items.

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The Science of Lightning

The Science of Lightning | Physics | Scoop.it
A view into some of the rarer types of lightning
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Have you heard of dark, volcanic or alien lightning?


Some lesser known aspects of lightning in this short popular science article. Lightning is an active reserch topic in atmospheric science.


via +Jenny Winder

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Ten kinds of matter

A cool discovery: substances can be divided into 10 kinds.…

Ten kinds of matter<br/><br/>A cool discovery: substances can be divided into 10 kinds.… | Physics | Scoop.it
Ten kinds of matter

A cool discovery: substances can be divided into 10 kinds.

The basic idea is pretty simple.  Some substances have time-reversal… - John Baez - Google+
Mikko Hakala's insight:

Theoretical condensed matter physics in Google+.

 

By looking at the symmetries of substances, 10 different kinds of matter can be found. Discussion of the issue in the main post and more in the comments thread. Post by +John Baez.

 

via +Jari Vasell

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First Ab Initio Method for Characterizing Hot Carriers Could Hold the Key to Future Solar Cell Efficiencies

First Ab Initio Method for Characterizing Hot Carriers Could Hold the Key to Future Solar Cell Efficiencies | Physics | Scoop.it
Berkeley Lab researchers have developed the first ab initio method for characterizing the properties of “hot carriers” in semiconductors. This should help clear a major road block to the development of new, more efficient solar cells.
Mikko Hakala's insight:

 

Computer simulations for hot carriers in solar cell  

 

* These are first steps towards ab initio characterization of hot carriers in solar cell absorber materials. The approach is density functional and many body perturbation theory, requiring only the structure as input.

 

* Electron-electron and electron-phonon loss mechanisms are evaluated, and predictions are given for the life time and mean free path of the hot charge carriers in silicon.


* It's an important work since thermalization of hot carriers is hard to evaluate but is the main efficiency-limiting mechanism in solar cells. Now these are first steps to predict this phenomenon purely ab initio. The method will help design and engineer more performant crystalline solar cell absorbers.  


* The PRL article:

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.112.257402

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NASA rover's images show laser flash on martian rock (w/ Video)

NASA rover's images show laser flash on martian rock (w/ Video) | Physics | Scoop.it
(Phys.org) —Flashes appear on a baseball-size Martian rock in a series of images taken Saturday, July 12 by the Mars Hand Lens Imager (MAHLI) camera on the arm of NASA's Curiosity Mars Rover. The flashes occurred while the rover's Chemistry and Camera (ChemCam) instrument fired multiple laser shots ...
Mikko Hakala's insight:

Spectrosccopic analysis of the Martian rocks after laser shots. 

 

More info:

http://phys.org/news/2013-12-martian-laser-surpasses-zaps.html

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The Little-Known Scientific Reason Your iPhone Earbuds Always Get Tangled

The Little-Known Scientific Reason Your iPhone Earbuds Always Get Tangled | Physics | Scoop.it
Knots really do form on their own as a matter of physics, not because of your personal lack of neatness.
Mikko Hakala's insight:

A perfect everyday physics article - Must read. 

 

Via @DoTryThisAtHome

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Ionic liquid boosts efficiency of CO2 reduction catalyst

Ionic liquid boosts efficiency of CO2 reduction catalyst | Physics | Scoop.it
(Phys.org) —Wouldn't it be nice to use solar- or wind-generated electricity to turn excess carbon dioxide—one of the gases trapping heat in Earth's atmosphere—into fuels and other useful chemicals? The process would store up the intermittent solar or wind energy in a form that could be used when ...
Mikko Hakala's insight:

How to reduce excess CO2 in the atmosphere? CO2 is one of the culprits for the greenhouse effect.

 

The research described in this Phys.org article used ionic liquid as a reaction medium for CO2 and the catalyst. The purpose is to reduce CO2 to CO, which can be further converted to more useful forms. The setup with ionic liquids was found to be better for the speed of the reaction and energy efficiency. Ionic liquids themselves are novel, tailorable liquids, and have promise to replace traditional solvents.

 

The work shows that there is progress in efforts for CO2 reduction, but apparently rather slowly. The basic fundamental research could play here a key role: The 'unknown' in the whole process is that one doesn't know exactly how the chemical reaction happens. That means that one doesn't know clearly what to modify in the process to make it happen easier (that is, how to lower the activation barrier for the reaction).

 

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Free Educational Physics Lecture Videos with Lecture Notes

Free Educational Physics Lecture Videos with Lecture Notes | Physics | Scoop.it
After teaching physics in a high school classroom for 13 years, I stepped out of the classroom to start Flipping Physics, a business dedicated to creating free, clear, concise and comedic physics educational videos.
Mikko Hakala's insight:

A nice and fun set of physics lecture videos. Many topics are covered, for example mechanics, electromagnetism, electrical circuits, refraction, interference. Some lectures also on modern physics.

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High-Tc superconductors: key similarities and differences between electron- and hole-doped cuprates unveiled by X-rays

High-Tc superconductors: key similarities and differences between electron- and hole-doped cuprates unveiled by X-rays | Physics | Scoop.it
Mikko Hakala's insight:

Experimental studies for the spin and charge excitations in doped cuprates. Insight into the energy - wavevector relation of the excitations is important since spin fluctuations are connected to the superconductivity in cuprates. These high-resolution resonant inelastic X-ray studies are an alternative to neutron scattering to investigate spin dynamics.

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