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Muhibija Buljubasic, 56, poses for photo with cutlery and a Samsung Galaxy S4 phone on his body and head in Srebrenik, February 23, 2014. Buljubasic discovered five years ago that he had the unusual ability to attach items to his body by radiating a special energy. Without making any special preparation, he was able to hold on to spoons, forks, knives and other kitchen appliances, as well as non-metal objects like remote controls and cell phones. REUTERS/Dado Ruvic
This fellow's portrait (above) seems to bear a resemblance to the decorations that are attached to a manniquin outside of a resturant in Baltimore (below). Perhaps this fellow (above) simply sprays a little adhesive on the backs of the spoons and cellphone to get them to stick to his body.0 -
The videos from the Breakthrough Prize in Fundamental Physics Symposium are now available to watch, follow the link below. The symposium was held on the 10th November at Stanford University and co-hosted by UC-San Francisco and UC-Berkeley.There was a panel discussion with Adam Riess, Brian Schmidt, Saul Perlmutter and Yuri Milner, and individual 20-minute talks from Nima Arkani-Hamed, Juan Maldacena, Andrei Linde, Stephen Shenker, Alexei Kitaev, Patrick Hayden, John Preskill, Nathan Seiberg, Joe Polchinski and Uros Seljak.
Link
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Yesterday's link, which spent some time discussing the discovery of Francium, reminds me of a Francium story that I've briefly mentioned before in a story of how we failed to trap Francium, but got the attention of someone else.
And, as I had mentioned, we (well, someone at TRIUMF) got a call from a watchdog station that tries to detect nuclear fallout, wanting to double-check on things. They knew the signature they were reading wasn’t from a bomb, but they knew something was up and guessed our target material: Thorium. When you blast that with energetic protons, you get lots of heavy isotopes.I ran across a paperfrom some folks at the monitoring facility
The United States and Canada have jointly established an experimental radio-aerosol monitoring station in Vancouver, British Columbia as part of the International Monitoring System for the Comprehensive Nuclear Test Ban Treaty. The purpose of this station is to monitor the atmosphere for the presence of anthropogenic radio-aerosols that could be indicative of nuclear explosion debris. The station has been engineered to achieve detection sensitivities that are approximately three orders of magnitude higher than conventional environmental and emergency preparedness monitors. Due to its ultra-sensitive measurement capability, the station has regularly detected micro quantities of radioisotope emissions from a nearby commercial production facility that would otherwise have gone unnoticed. The major isotope, 123I, was identified by spectroscopic analysis and correlated to the facility through source emission data.TRIUMF would probably not be considered a commercial production facility. Although it's possible they were making this radioisotope in conjunction with a commercial partner, I'm guessing that it was a medical radioisotope production facility. Same kind of sleuthing for the monitoring station, but a different culprit.
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My Great-Great-Aunt Discovered Francium. And It Killed Her.
Interesting story, and an astute observation:
There is a common narrative in science of the tragic genius who suffers for a great reward, and the tale of Curie, who died from exposure to radiation as a result of her pioneering work, is one of the most famous. There is a sense of grandeur in the idea that paying heavily is a means of advancing knowledge. But in truth, you can’t control what it is that you find — whether you’ve sacrificed your health for it, or simply years of your time.Hard work and intelligence is no guarantee of success, and some success is just pure luck. There are a number of scientists out there who will never win a Nobel, and it has nothing to do with their talent.
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This is fun. I wonder if I can find a miniature copper slinky for sale, so I don't have to wind my own …
[youtube:http://www.youtube.com/watch?v=J9b0J29OzAU]
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Here's another timing article that popped up right after Daylight Saving Time ended. (Perhaps a heavy sigh is required here. I'm not sure why the rash of stories has hit is) I'm predisposed to like it, since it's largely focused on our work, but unlike some articles I've critiqued lately, it doesn't focus on one US timekeeping group and ignore the other one
By law, today the USNO shares the responsibilities for measuring and disseminating time with the Time and Frequency department of the National Institute of Standards and Technology (NIST), which sits under the US Dept. of Commerce. The USNO sets time for GPS and navigational systems and the Dept. of Defense, while NIST sets the standard for the financial sector and other civilian applications. (NIST receives several billion computer requests per day for this service, and broadcasts time to over 50 million radio clocks, wristwatches, and other clocks with radio receivers.) While there is a lively cooperation between the two agencies charged with telling the time—and the occasional competition over talented PhDs—they mostly operate in different domains: NIST performs most of the cutting-edge research, while USNO focuses on counting and disseminating the time to the military, as a matter of national security.I don't even object to the observation that NIST is doing most of the cutting-edge research — they are. Their frequency standard results are amazing. Our research in that area is different, since it focuses on developing continuously-running clocks.
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I have published many articles indicating that the Lorentz force law is flawed. In order to help people to better understand my work, I make a brief guide through the 5 intuitive paradoxes, 2 analytic computations, 3 numerical computations and 7 experiments, all of which are examples of the flaw of the Lorentz force law. The corrected magnetic force law that I propose is identical to the Lorentz force law for closed coils but respects Newton’s third law.
Please read the article at
Explanatory summary for my studies about the Lorentz force law pdf or word
Explanatory summary for my studies about the Lorentz force law http://pengkuanem.blogspot.com/2014/11/explanatory-summary-for-my-studies.html
or https://www.academia.edu/9529415/Explanatory_summary_for_my_studies_about_the_Lorentz_force_law
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Rohinni's Lightpaper Is Incredibly Thin, And Printable
In its current state, Lightpaper is manufactured by mixing ink and tiny LEDs together and printing them out on a conductive layer. That object is then sandwiched between two other layers and sealed. The tiny diodes are about the size of a red blood cell, and randomly dispersed on the material. When current runs through the diodes, they light up.It'll be interesting to see how people use this if the product becomes widely available.
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… except I didn't say "fudge"
"Get Me Off Your F---ing Mailing List" is an actual science paper accepted by a journal
They don't say fudge in the paper, either.
There are a bunch of journals out there, many advertising themselves as "open access" that will print basically anything — for a fee. Many claim to be peer-reviewed, as does the International Journal of Advanced Computer Technology, who accepted the paper.
IJACT … is a highly-selective, refereed journal. Manuscripts that appear in the IJACT Articles section have been subjected to a tiered review process. This includes blind review by three or more members of the international editorial review board followed by a detailed review by the IJACT editors.Although feedback ordinarily will be given, the editors reserve the right to reject a manuscript for publication without a rationale for their decision.Oh, really? A reviewer marked its appropriateness as "excellent". It was accepted; the only reason it wasn't published was that the submitter didn't want to pony up the $150 it would have taken.
The article chronicles other deliberately substandard submissions that were submitted to, and often accepted by, similar journals. Their sleaziness can't be blamed on Schwartz.
[youtube:https://www.youtube.com/watch?v=11q4q3S57jE]
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[youtube:https://www.youtube.com/watch?v=pnbJEg9r1o8]
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Got my internet working (yay! It was
the salmon moussea dead modem) and completed a trip to a DARPA program review, where I got to see lots of neat things I can't blog about. Sorry.
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I did not realise this until today, but I share my birthday with John Wallis (23 November 1616 – 28 October 1703). Wallis made contributions to infinitesimal calculus, analytic geometry, algebra and the theory of colliding bodies. He is best known for the infinity symbol $latex infty$.Wallis was also a code breaker and used his mathematical skills during the Civil war to decode Royalist messages for the Parliamentarians.
Link
John Wallis Wikipedia.
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More warnings about a shortage of STEM graduates. Where are these messages coming from? There is no shortage, many graduates in engineering for example are forced to work in jobs that are nothing to do with their degrees, or even worse they are in non-graduate jobs.Engineering needs to emphasise its creative side to encourage more young people to take it up as a career.Sir John O'Reilly
This is fine. The fields of science and engineering do require some creative thinking. There is an element are art to this.
But I am worried about the continual message of a lack of STEM graduates where in reality many are unemployed. I really don't understand the B.S. here.
Link
'Embrace engineering's creative side' to fix skills crisis
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To my previous proofs of the inconsistency of the Lorentz force law some have objected with dubious arguments such as: magnetic force on displacement current, magnetic force inside a magnetic shield. Also, my mathematical demonstrations using triangular coils are although exact but too hard to follow. So, I propose a much more intuitive and simpler counter-example here, a 3D folded rectangular coil, Figure 1. Figure 2 is the right view showing the vertical sides BC and CD.
Please read the article at
Self force of a 3D coil http://pengkuanem.blogspot.com/2014/11/self-force-of-3d-coil.html
or Self force of a 3D coil https://www.academia.edu/9413326/Self_force_of_a_3D_coil
Self force of a 3D coil pdf or word
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Schools watchdog Estyn says too many pupils struggle with the basics of mathematics and maths skills were "at best, average" in more than half of schools inspected in Wales last year.The mathematics skills and the teaching methodologies in Welsh schools seems to be a continuing source of worry.
The attitude that it is okay to not be good at basic mathematics needs to change. There is some social acceptability in being poor in mathematics. I am sure that when English teachers, lets say at a party, explain that they are English teachers are not met with a funny look and the response "I hated English at school and I cannot read or write"...
Link
Concerns over pupils' maths skills at half of Welsh schools BBc News
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Internet's down at home, so my grand plan to surf the net, write, and then post has been dashed. Time to fire the mice.
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A summary of the physics of the new movie Interstellar on LinkedIn: Interstellar link
Never say never. Though it sure seems that interstellar travel is extremely unlikely. For Alcubierre warp drive, one needs stupendous amounts of "negative energy". Although it exists according to Quantum Mechanics -- it is found in quantum vacuum energy -- no one knows how to access it, let alone in great quantities. Nonetheless, warp drive is under study at NASA. See http://www.decodedscience.com/faster-speed-light-nasa-looks-warp-drive/40698 .
As to wormholes, although allowed by the mathematics of general relativity, no one knows if they really exist. Plus quantum issues say its throat would be almost instantly pinched off by EM and vacuum energy. Thorne proposes using negative energy to keep the throat open, but this again requires tremendous amounts of negative energy. And quantum mechanics says this "exotic matter" must be extremely narrow and lasts only for the briefest of times.
Highly improbable to say the least. But wonderful to imagine.
(I will be giving talks on all this at the San Francisco Star Trek convention on Dec. 13 and 14. If you are in the area, come join the fun.) http://www.creationent.com/cal/st_sanfrancisco.html
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Quite regularly one will come across a website, blog or some thread on a forum that says the gravity is just electromagnetism. For sure they are not the same. However, I am not sure what would constitute the 'nail in the coffin' for all these clams.With this in mind, I am not going to try to debunk every such claim. However, I think the reason for this seeming equivalence comes from the static limit. In this limit it is true that there are many formal similarities between Newtonian gravity and electrostatics. In fact there are many formal similarities in the full classical theories, both are very geometrical in nature, but I won't go into details here.
I just wanted to point out one very clear difference between gravity and electromagnetism that can be seen in this static limit. That is the lack of a generalisation of the equivalence principal for electromagnetic theory. This principal in gravity is very important and one that I will comment on in due course.
The static limit
I am guessing that we have all seen Coulombs law for electrostatics and Newton's law for gravity. Let me just write them down
$latex F = k frac{qQ}{r^{2}}$,
where $latex k$ is Coulombs constant, it is a measure of the strength of the electrostatic force and $latex q$ and $latex Q$ are the electric charges of two point particles. The above expression is the electrostatic force between two such charged particles.
Similarly we have Newton's law of gravity
$latex F = G frac{mM}{r^{2}}$,
where $latex G$ is Newton's constant which measures the strength of the gravitational force and $latex m$ and $latex M$ are the masses of two point particles. The above expression measures the gravitational force between these particles.
These expressions for the forces should be seen as the static non-relativistic limit. I just mean that as long as the particles are moving slow enough then the change in the fields can be viewed as instantaneous. This is okay for many applications, but it is not the full picture. However, it is the one you see at high school.
The formal similarities at this level are clear. You just need to swap constants and interchange charge and mass. But this does not mean they are the same, and there is a subtle issue here. Before that we need Newton's law of motion
Newton's second law
Newton's second law tells us that the force exerted on a particle is proportional to the acceleration of that particle. Moreover, the constant of proportionality is the (inertial) mass.
$latex F = m a $.
That is all we will need.
The gravitational equivalence principal
Let us think of the particle of mass $latex m$ as a test particle. That is we will think of how it is moving in the gravitational field generated by the particle $latex M$ and that it does not generate a gravitational field of its own. This approximation is good for small objects moving in the gravitational field of big objects; say planets around a star or satellites in orbit around the Earth.
Now we can examine how the small mass is influenced by the big mass. We should just equate the two expressions due to Newton
$latex ma = G frac{mM}{r^{2}} $,
for which we can solve for the acceleration
$latex a = G frac{M}{r^{2}}$.
We notice a very amazing thing. The small mass cancels from both sides of the equation. (We assume that gravitational mass and inertial mass are the same. This seems to be case in nature.)
This means that the motion of the test particle does not care about any of the intrinsic properties of that particle. The only things it does care about is the initial position and velocity. This is one form of the equivalence principal which has it's roots in the experimental work of Galileo- acceleration of a test particle due to gravity is independent of the mass being accelerated.
Thus, really all the information about the test particles motion is encoded in the gravitational field alone. All test particles whatever their mass will behave the same. This is the clue that gravity can be formulated very intrinsically in terms of space-time geometry alone; this leads to general relativity which is not the subject for today.
The electromagnetic version
Now let us play the same game with electrostatics...
$latex ma = k frac{q Q}{r^{2}} $,
where we think of the test particle $latex (m, q)$ moving in the electric field generated by the particle $latex (M,Q)$. Now solving for the acceleration gives us
$latex a = k left(frac{q}{m}right) frac{Q}{r^{2}} $.
Now we see the difference. The motion of the test particle does depend on the intrinsic properties of that particle, namely the charge-mass ratio. There is no similar statement like for gravitational physics; there is no equivalence principle.
Closing remarks
Everything above is done in a particular limit of the full classical theories. The same picture is true when we examine the motion of test particles in general relativity and the Lorentz force in electromagnetic theory. I have chosen these limits because I think this is clear and also the source of the instance that gravity is just electromagnetic theory. I have pointed out one clear and explicit difference.
One can do the same with Coulomb's law for the magnetic force. Although magnetism is a bit more complicated we can examine the situation for point-like poles. This is okay for small enough poles that are well separated. You will reach the same conclusion that there is no equivalence principal in this situation. Thus, gravity is not magnetism either.
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[youtube:https://www.youtube.com/watch?v=9ZEdApyi9Vw]
[youtube:http://www.youtube.com/watch?v=bxE09URykdg&list=UUYKfAzPEXMQsGtNfBCNa_BA]
During Expedition 40 in the summer of 2014, NASA astronauts Steve Swanson and Reid Wiseman — along with European Space Agency astronaut Alexander Gerst — explored the phenomenon of water surface tension in microgravity on the International Space Station. The crew "submerged" a sealed GoPro camera into a floating ball of water the size of a softball and recorded the activity with a 3-D camera. (Video: NASA)Note: You will need red-blue stereoscopic 3D vision glasses to view the video.Bottom one is the 3D version, in case you couldn't figure that out.
The big question for me is how my brother Steve kept being an astronaut a secret all these years.
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When I was on vacation a few weeks back, a friend had related a story to me of a proprietor of an electronics shop who also repaired TVs, but was lamenting that TV repair business has been dropping off, for similar reasons as described by Rhett in The End of the Throwaway Appliance
Why would you repair an appliance if it is just a little bit more to buy a new one? Even if I did spend $100 to fix my washer, who knows – something else might break next week. In too many cases it’s just simpler to buy a new thing than to repair. I think this sucks.I don't share Rhett's optimism that the problem of throwaway electronics can be fixed — his solutions will work, but only a sliver of the population has the technical skills and/or tools to implement them.
(Another reason the TV repairman's business was dropping off was that it was taking weeks to get parts for one of the popular brands, and nobody is willing to wait weeks to get their TV back, when a new and bigger/better on is available right now.)
I can think of an alternative.
Here is the real problem. I wasn’t exactly sure which part was broken. The control panel costs about $100 and the control board has a price around $120. On a gamble, I could order the control panel (pretty sure that’s where the problem was), but what if I’m wrong? I could possibly return the piece but the whole process could take a significant amount of time.What if you had ten broken washers, or TVs, or whatever, of the same make and model, or at least had compatible internal parts? They would probably not all have the same problem, so you could swap parts around and get some of them working, either as a diagnosis (you'd then buy the parts you needed) or as a working product. If people are just tossing their old products out, that may require a trip to the landfill or some other disposal site — an enterprising person could offer to haul them away — at no cost to the owner! — and then sell the fixed machines. It's mainly a matter of how many you could fix and sell in a given amount of time, and having enough space to do the work.
I know back in grad school I'd seen ads saying "we'll haul away your old washer/dryer", so I assume that's what they were doing, but I don't know if that's still a thing with the more computerized machines of today. I think that this is a more viable solution to the throwaway appliance — leverage some economy of scale to make it into a refurbished appliance.
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On Friday 7th November I will be giving a short talk to physics students entitled 'Fermions in Physics: from anticommuting variables to supermanifolds', as part of the Ogólnopolska Sesja Kó? Naukowych Fizyków.This translates as 'Scientific Session of the Nationwide Circle of Physicists'. This year the session is in the Tricity area.
I hope to tell them a little about the passage from the canonical anticommutation relations to Grassmann algebras and then supermanifolds. I have 45mins to get them interested in this geometric side of mathematical physics.
I will post the slides here after the event, but they may not make much sense without me telling this you this story.
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It's time for another installment of "That's Not A Clock (it's a stopwatch)"
New Clock May End Time As We Know It. This is the same technology that I'd linked to back in January, and NPR did something back then, too. I thought maybe this was prompted by a new paper, but the story may have just been motivated by our daylight saving shift last weekend.
I completely agree with Tom O'Brian — time is a human construct, in that it's abstraction we came up with (but then, so is length). But I have an issue with saying that NIST has America's master clock, while ignoring the one that resides in Washington DC, run by the navy, and that Tom O'Brian is America's official timekeeper (i.e. singular). Sins of omission.
This new clock can keep perfect time for 5 billion years.…if it ran continuously. But it doesn't. Jun Ye gave a talk on this at DAMOP this past summer, and someone asked him if/when any of these optical lattice devices were going to run as actual clocks, and how long they could run. The answer was (paraphrasing here) "about 24 hours, because people need to sleep." NIST isn't going to be pushing very hard to extend that, because that's not their job. As he put it, once you get to the noise limit of the device, they sort of lose interest in running it any longer.
The rest of it is pretty good for a pop-sci piece, aside from the observation that (as Matthew Francis tweeted at me) "end time as we know it" seems a trifle hyperbolic. In other words, what do you mean, "we"? The issues of trying to synchronize clocks are not going to affect the vast majority of people. It's a very interesting technical challenge, for reasons described in the article, and once people come up with applications that require picosecond-ish level of timing or better, it's something we'll have to solve. But it's not going to affect whether you're late for work or what time the game comes on.
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I was trying to track down some details of some work-related history and ran across this, which just happened to have my search terms in it (though not in close proximity in the text). It's a Congressional hearing from 2006 on how the recent NIST Nobel laureates view science policy.
This is not today's congress, i.e. this was not chaired by Lamar Smith, and all that that engenders, so even though the GOP hasn't been particularly cozy with science in some time, this dates to a time when things weren't quite as bad as today. Plus, this hearing wasn't discussing social science or global warming.
It's a transcript, so it's not polished and there's a lot of fluff, but there are parts that are quite good. I know from experience that Bill Phillips (Nobel in '97) and Eric Cornell ('01) are good science communicators; I can't recall ever hearing Jan Hall ('05) give a talk but his testimony is pretty clear as well.
The hearing will address these overarching questions:1. Why has NIST been so successful at cultivating Nobel Prize winners?2. What are the implications of the Nobel Prize-winning research at NIST and how can that work get used outside of NIST?3. What steps are most necessary to improve U.S. performance in math, science and engineering, and U.S. competitiveness?What directed my attention to the transcript was related to Bill Phillips' work on laser cooling and trapping
One application of low-temperature physics is technology to improve the accuracy of atomic clocks. By cooling atoms of cesium, scientists have made atomic clocks that are a billion times more accurate than an ordinary wristwatch.From Bill's testimony:
Today, laser-cooled atoms define time. At the naval observatory, they keep time for our military. They synchronize GPS, which guides everything from military jeeps to commercial aircraft. NIST's standard clock is accurate to less than one second in 60 million years. We like to call this "close enough for government work."The naval observatory mention was one part that garnered the hit on Google; apparently he talks us up on pretty much every occasion. We invited him out to visit us last summer when we declared our fountain clock ensemble to be fully operational (and were not subsequently destroyed by the rebel alliance), and got to hang out for a while. One thing we talked about is what he discusses below on government investment in science.
Later on in his prepared statement he describes how he pursued laser cooling — first as a bit of a hobby, with scrounged equipment, but later on as a primary research investigation, with proper funding. And, I might add, with minimal interference from a bureaucracy which might demand immediate commercial application from research (just the normal government bureaucracy to inhibit work). He speaks of realizing the application to clocks, but those clocks and frequency standards didn't come to fruition for several decades, and even then that was pretty fast for basic research to get going, to make a discovery, and for that discovery to have a significant impact. Such is the scale of science, and that's the reason why scaling back on government investment will not be noticed at the commercial level for quite some time. Inertia is the problem here. We're coasting on older investment, and we won't be able to quickly (if ever) regain any lead we have should we lose it. You can't recreate a decade's worth of research overnight, even if you threw a lot of money at the problem. As the saying goes, it takes a woman nine months to make a baby, but you can't get nine women together to make a baby in a month. There's no substitute for continued, deliberate investment in basic research.
Bill Phillips, in his prepared statement
The invention of the transistor at Bell Telephone Labs set the stage for a booming electronics industry that has sustained much of the U.S. economy. It came from a strong and sustained program in basic research at Bell Labs, one that was mirrored in other industrial labs like RCA, Raytheon, Ford, Xerox, IBM, and so forth. Today, many business analysts seriously contend that AT&T never got a significant return on its research investment and denigrate the value of any long-range, basic research in any industry, focusing instead on very short-term return on investments. Today, Bell Labs is a shadow of its former self in regard to basic research and that sort of far-sighted support of research has virtually disappeared from American industry. I don't know if we can ever expect to return to the golden age of industrial research, but I strongly believe that we must, as a nation, regain and maintain that level of basic research if we are to remain competitive in a world economy. If industry cannot or will not take its traditional share of this responsibility, I believe that government must compensate.I think that this is not happening, and things have gotten worse in the last several years as science funding has been cut. We'll wake up in a decade or two and wonder why so much of the innovation is happening elsewhere and it's going to be because the government stopped funding science at a level necessary to move forward, mainly because of a powerful few who hated science and blocked its progress. Our "return on investment" can't be the criterion we use to decide on basic research, because you simply don't know what you're going to find.
From Eric Cornell's statement
The big question is what is going to be the big new industry of 2020? If I knew the answer, I would not be here in front of you testifying--I'd be off setting up my own high-tech venture capital company instead. No one knows the answer for sure, that is why scientific research and discovery is so important. Without knowing for sure what the next big thing will be, we can remain cautiously optimistic that that big thing will be an American thing.Remember, this was from 2006. I wonder if his take would be different today, given trajectory of science funding? But again, note the underlying thought here: it's research, and you don't know what you're going to find until you go out and find it. Any and every interruption can stop research, but it requires time to get it going again. All too often you have to go back to square one and start over from scratch.
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Blog post: swansont: Cold but Safe
in SFN Blogs
Posted
The gloves don't work
Scaling laws, related to why kids may be better off with mittens, and why cold fingers on a child also tells us we won't be attacked by giant ants.
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