An invisibility cloak (DIY, sort of)

Credit: Lawrence Berkeley National Laboratory, US Government Work, Public Domain

  If everybody could have an invisibility cloak then we would all be invisible.  We don't "see" an advantage to that.  But building a "room temperature full optical wavelength" invisibility cloak (that presumably runs on DC power) would be challenging to build!  Not the sort of thing we would expect from the folks at Apple but perhaps the Fraunhofer Institute/s?  We suggest you look at the ("pay $") entry in Applied Physics Letters*: http://apl.aip.org/resource/1/applab/v102/i1/p014102_s1?isAuthorized=no.  A better source may be the related article in Phys.Org: "Nearly perfect, ultra-thin invisibility cloak could have wide practical applications".

The invisibility cloak appears to have the shape of a "true cloak" or more like a "poncho shape".  It's thickness/thinness is explained by the researchers as being made of a homogeneous construction of resistors. The secret/s of its invisibility property is said to be due to permittivity and permeability.  It is not known which wavelengths or frequencies in which it is "invisible".  For a "non-action video" - that may have technical issues - one was developed by TechNetworkNews.  You may have to look into the ALP* article for a demonstration, if possible.

The "prior art" of the invisibility cloak was being developed on the basis of metamaterials.  However that last link (from the Wikipedia) is current up to only 2010.  But the prior art does date back to 2005/2006.  For a good working development (based on nanomaterials) see the YouTube video from/by Ali Aliev.  For more on that development see our Examiner.com article.  If you read the article you should see that that invisibility device - as is - might be impractical for your room temperature full optical wavelength invisibility cloak.  But, it is apparently invisible in the optical range of light visible to human eyes.

For more on the recent (November 2012) invisibility cloak/device from Duke University see our other Examiner.com article.  Like some invisibility devices it does not cover the optical range and works only in the microwave range.  However, it does give a working demonstration that the next advance to the optical range cloak could be possible.

The prior art to that work was the research and development of metamaterials (earlier, more) for "fishnet" invisibility cloaking - a design which was in favor.  See the articles "Low-loss negative-index metamaterial at telecommunication wavelengths" and "Development of bulk optical negative index fishnet metamaterials: Achieving a Low Loss and Broadband Response Through Coupling".  The thinking at the time was the development of a "layered, pierced metamaterial" with a negative refractive index.

Credit: Infrared.als.lbl.gov, US Government Work, Public Domain, http://infrared.als.lbl.gov/content/the-news/1-latest-news/152-invisibility-shields-one-step-closer-with-new-metamaterials-that-bend-light-backwards

The layers of materials might be nano-scale coatings of silver sandwiching a dielectric (like Magnesium fluoride).  The advantage/s of silver being it's high reflectivity and "damping" properties.  Magnesium fluoride was seen to have an advantage in its relative clarity, we surmise.  Other dielectrics might be worth reviewing at a later time.  A superconductor might also replace silver due to it's high permeability.  However, superconductors (at this writing) have disadvantages like a very low operating temperature and lack of optical clarity.  Would elemental Niobium work in this case?  We can't say.

Silicon - combined with metallics - was also a research topic in 2009.  However, the cloak developed by the Berkeley Lab was said to be invisible only in the near infrared wavelength - slightly outside the range of human optical visibility.  However, it too, was something of a "fishnet" material.  (See also the video at top of the post.)

Credit: Lawrence Berkeley National Lab, US Government Work, Public Domain

For more information you may wish to search Google Books.  If we may point out one it might be "Structured surfaces as optical materials".  We'll have to get back to you next time there is another advance towards a "room temperature full optical" invisibility cloak.

© Copyright 2013 and Patent Pending

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Nightmareliner

Nightmareliner -

(Updated Sunday, 1_20_2013 see below.  And again 1_30_2013.)

The VERY unfortunate and unfunny conflation of "Dreamliner" with nightmare/s or nightmarish events seen with the Dreamliner (Boeing's 787 airliner).

We'll go to the latest press release from the NTSB: "Second Investigative Update of Boston Boeing 787 Battery Fire".  Yes, you read that right, 'battery fire'.  Seems that the Lithium-ion batteries for the jets are catching fire (for "unknown reasons") with leaks of the lithium electrolyte fluid a possibility?  An electrolyte leak could make fire spread and fire conditions even worse - fortunately one of the incidents required only "just about one half hour of extinguishing by the emergency staff".

The NTSB release almost occurred simultaneously with the FAA Dreamliner grounding announcement.

Credit: NTSB, US Government Work, Public Domain

As you can see posted above, the NTSB posted photos of burned 787 batteries with its PR.  Well, shouldn't they have fire-tested those batteries before?  Well, yes and no, we found a PowerPoint presentation from the FAA regarding the fire testing of smaller commercial lithium ion batteries - but nothing yet on the full-scale commercial airline format.  At least nothing related to the full-scale battery was found in our search.



Presumably, GS Yuasa was awarded the *contract to supply the full-scale 787 aviation batteries.  Link to the (presumed) spec sheet here.  The spec sheet (as of this writing) states that the battery has a "Prismatic Shape" - which doesn't appear to resemble the photo/s supplied by the NTSB.  What shape exactly is the battery form supposed to be?

If we read further down the spec sheet (under "Safety and Handling") we see that the "cell design details and specification are subject to change without notice."  We sincerely hope that that verbiage wasn't approved in the *original contract.

The "Safety and Handling" section goes on to read: "Inappropriate handling or application...can result...even in the possibility of smoke generation or fire".

Yes, that is a known safety/hazard factor in Lithium ion batteries!  See the link to the above PDF.  Also, see the reports from the Consumer Product Safety Commission dating back to 2006.  Of course, the GSY contract award for the specified batteries pre-dates those 2006 incidents.

We also saw proposed safety labeling for the Lithium ion batteries in the Federal Register (2010). 

Credit: Federal Register, U. S. Government Work, Public Domain

Further safety and hazard precautions are found for Lithium ion batteries in what appears to be a sample military grade battery Material Safety Data Sheet.  Please note: the manufacturer of the battery for our sample MSDS is not involved or implicated in the current Dreamliner battery fires!

And the Wikimedia Foundation has an Ebook available on Google Books - and it also contains similar recommendations and precautions.

The element Lithium, itself, is rated as non-flammable but has some other safety issues on its own.  The problems appear to arise in the Lithium battery - and its electrolyte (when leaked) - in certain applications like the Nightmareliner.   Er, sorry, we mean the "Dreamliner".  To be fair in the end, Boeing has also posted their own PR statement on the incidents (FAA 787 Action).

Update 1_20_2013 The FAA #designated Boeing to generate LiIon battery data #Nightmareliner http://online.wsj.com/article/SB10001424127887324624404578253010041254492.html#articleTabs%3Dvideo Via @WSJ  Most of the video reported by Andy Pasztor, LA WSJ Sr. Correspondent.

Update 1_30_2013 Boeing's Batteries Draw Criticism as Dreamliner Probe Continues | Autopia | Wired.com http://www.wired.com/autopia/2013/01/boeing-787-battery-design-musk/



Update 2_05_2013

Boeing Asks FAA to Lift Grounding of Dreamliners for Test Flights http://soc.li/YoyaG3I Via CNBC

Update 2_10_2013

Via Reuters

Expect Dreamliner delays, Boeing tells airlines http://reut.rs/1501qgw via @reuters

 

Update 3_06_2013

 

Analytical theory may bring improvements to lithium-ion batteries http://phys.org/news/2013-03-analytical-theory-lithium-ion-batteries.html

 via @physorg_com

Analytical theory may bring improvements to lithium-ion batteries http://www.purdue.edu/newsroom/releases/2013/Q1/analytical-theory-may-bring-improvements-to-lithium-ion-batteries.html#.UTYx6t6AdCo.twitter

How lithium electrochemical research might save the Boeing Dreamliner http://www.examiner.com/article/how-lithium-electrochemical-research-might-save-the-boeing-dreamliner

via @examinercom

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Huge LQG

The Huge LQG or The Penultimate LQG -

The news about the Huge LQG is still posted on Reuters/News Daily as of this writing and may still be found on Science Daily and even in the Wikipedia.  The discoverers posted their findings in the Arxiv paper "A structure in the early universe at z* ~ 1.3 that exceeds the homogeneity scale of the R-W concordance cosmology" by Roger G. Clowes, Luis E. Campusano, et. al..

This penultimate structure (LQG) is mind-bendingly large and even distorts our concepts of relativity and the cosmological principle.  In "classical cosmology" it was thought that the CP limited universal structure sizes to about ~ 370 Mega-parsecs (Mpc).  The newly discovered Huge LQG has an estimated size of ~ 500 Mpc - which is stupendous.  Even greater is it's estimated longest dimension: ~ 1240 Mpc.

We also refer to it as the Penultimate LQG as nature is full of surprises.  That is we expect an even larger LQG structure or hyper-structure may yet be discovered and described - an Ultimate LQG.  The red-shift* ("z") implies that the Huge LQG lies far in the past and a long, long way away.  The same may apply for the hypothetical Ultimate LQG.

This appears to upset the old (1977) documentary (and book) "Powers of Ten" and the orders of magnitude described.  The book was written by the late great Philip Morrison and late wife Phylis Morrison.  The office of Ray and Charles Eames (designers) was deeply involved with both projects.  The previous high limit on order of magnitude (according to these good folks) was 100 million light years (~ 3E x 7 Mpc) or 10E x 24 meters.

The 7 Mpc order of magnitude (and the previous limit of approximately 150 Mpc) has long since been toppled apparently by the discovery of the Huge LQG.  This begs a question - how does the Huge LQG compare in size with other large "structures" and "voids" in the known universe?  How do they compare with the size of the universe?

Credit: NotOnTwtr and a variety of sources.

Assuming that the numbers we were about to play with were best estimates and best measurements available we put the data together in a graphic and a table.

Our own Solar System is at too small a scale to give a relative comparison.  The same goes for our own Milky Way.  The Universe (estimated size - which is likely quite wrong!) would cover the whole chart and obscure the available comparisons!

Our own Local Group of galaxies "disappears" in the graphic due to it's relatively small size/volume.

The Great Wall refers to the Sloan Great Wall and is roughly equal in size to the "average" LQG.

The Huge LQG is slightly "larger" than the estimated size of the Giant Void.

The size comparisons with the Huge LQG suggest non-randomness.  However, we invite you to make your own conclusions.  Until the discovery of a larger structure (like the hypothetical Ultimate LQG) our universe may be seen as "expanding" - but is a non-random structure itself.

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