Thursday, March 16, 2017

DOE's Office Of Science Faces Disastrous Cuts

The first Trump budget proposal presents a major disaster for scientific funding and especially to DOE Office of Science budget.

President Donald Trump's first budget request to Congress, to be released at 7 a.m. Thursday, will call for cutting the 2018 budget of the National Institutes of Health (NIH) by $6 billion, or nearly 20%, according to sources familiar with the proposal. The Department of Energy's (DOE's) Office of Science would lose $900 million, or nearly 20% of its $5 billion budget. The proposal also calls for deep cuts to the research programs at the Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA), and a 5% cut to NASA's earth science budget. And it would eliminate DOE's roughly $300 million Advanced Research Projects Agency-Energy.

I don't know in what sense this will make America "great again". It is certainly not in science, that's for sure.

Zz.

Born Rule Confirmed To An Even Tighter Bound

I must say that I might have missed this paper if Chad Orzel didn't mention it in his article. Here, he highlighted a paper by Kauten et al. from New Journal of Physics (open access) that performed 5-slit interference test with the purpose of detecting any higher-order interference beyond that predicted by the Born rule. They found none, and imposed a tighter bound on any higher-order effects.

As Orzel reported:

That's what the NJP paper linked above is about. One of the ways you might get the Born rule from some deeper principle would be to have it be merely an approximation to some more fundamental structure. That, in turn, might very well involve a procedure other than "squaring" the wavefunction to get the probability of various measurement outcomes. In which case, you would expect to see some higher-order contributions to the probability-- the wavefunction cubed, say, or to the fourth power.
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Sadly, for fans of variant models of quantum probability, what they actually do is the latter. They don't see any deviation from the ordinary Born rule, and can say with confidence that all the higher-order contributions are zero, to something like a hundredth of a percent.

Of course, this won't stop the continuation of the search, because that is what we do. But it is amazing that QM has withstood numerous challenges throughout its history.

Zz.

Sunday, March 12, 2017

The Weak Nuclear Force

I'm going to highlight this latest video by Fermilab's Don Lincoln for a number of reasons. First, the video:



Second, this is one video packed with a number of very important and illuminating stuff. First he explains about the concept of "spin" in both the classical and quantum picture. This is important because to many people who do not study physics, the word "spin" conjures up a certain idea that is not correct when applied to quantum mechanics. So this video hopefully will enlighten the idea a bit.

But what is more fascinating here is his brief historical overview of the first proposal of the connection between the weak interaction and spin, and how Chien Shiung Wu should have received the Nobel Prize for this with Yang and Lee. This might be another case of gender bias that prevented a brilliant Chinese female physicist from a deserving prize. Considering the time that she lived in and the societal and cultural obstacles that she had to overcome, she simply had to be just too outstanding to be able to get to where she was.

So this is one terrific video all around, and you get to learn a bit about the weak interaction to boot!

Zz.

Friday, March 10, 2017

APS Endorses March Of Science

The American Physical Society has unanimously endorsed the upcoming March for Science.

I'll be flying out of town on that exact day of the March, so I had decided a while back to simply contribute to it. I get the sentiment and the mission. However, I'm skeptical on the degree of impact that it will make. It will get publicity, and maybe focuses some of the issues, especially funding in the physical sciences, to the public.

But for it to take hold, it can't simply be a one-day event, and as much as I've involved myself in many outreach programs, I still see a lot of misinformation and ignorance among the public about science, and physics in particular.

Here's something I've always wanted to do, but never followed through and lack the resources to do it. How about we do something similar to a family tree genealogy. But instead of tracing human ancestors, we focus on technology "family tree". I've always wanted to start with the iPhone capacitive touch screen. Trace back up the technology and scientific roots of this component. I bet you there were a lot of various material science, engineering, and physics that were part of various patents, published papers, etc. that eventually gave birth to this touch screen.

What it will do is show the public that what they have so gotten used to came out of very basic research in physics and engineering. We can even list out all the funding agencies that were part of the direct line of "descendants" of the device and show them how money spent on basic science actually became a major component of our economy.

By doing this, you don't beat around the bush. You TELL the public what they can actually get out of an investment in science with a concrete example. And it may come out of areas that they never made connection before.

Zz.

Thursday, March 09, 2017

Time Crystal

This is quite an astonishing feat. It was only back in 2012 that Frank Wilczek proposed the possibility of a "time crystal", where a certain symmetry repeats in time, rather than in space. This was followed soon enough by a formal proposal for such a crystal. And now, we appear to have two experimental evidence.[1,2]

Potter is part of the team led by researchers at the University of Maryland who successfully created the first time crystal from ions, or electrically charged atoms, of the element ytterbium. By applying just the right electrical field, the researchers levitated 10 of these ions above a surface like a magician’s assistant. Next, they whacked the atoms with a laser pulse, causing them to flip head over heels. Then they hit them again and again in a regular rhythm. That set up a pattern of flips that repeated in time.

Crucially, Potter noted, the pattern of atom flips repeated only half as fast as the laser pulses. This would be like pounding on a bunch of piano keys twice a second and notes coming out only once a second. This weird quantum behavior was a signature that he and his colleagues predicted, and helped confirm that the result was indeed a time crystal.

Like I said, this is quite a feat to come up with a scheme to be able to create and test this.

Zz.

[1] J. Zhang et al., Nature 543, 217 (2017).
[2] S. Choi et al., Nature 543, 221 (2017).

Monday, March 06, 2017

The Race To Make Quantum Computers

We still don't quite have a truly-accepted working model, even from D-Wave. So it is interesting to see this latest news of both Google and IBM launching projects to produce and eventually sell these quantum computers.

The folks from Google's Quantum AI Laboratory wrote a comment in Nature, while IBM's intention is reported in the news.

With the Chinese company Alibaba collaborating with the Chinese Academy of Sciences to also go into this area, the next several years will be fascinating to watch.

Zz.

Sunday, March 05, 2017

Raman Spectroscopy Used To Detect Skin Cancer

I found this piece of news while reading the Flash Physics section on Physics World. And if you've followed this blog for a while, you know that I will highlight this without any shame.

Chalk this up to another important application of something that came out of physics research and subsequently finds a usefulness in medical diagnostics. Many of us in Material Science/Condensed Matter Physics/Chemistry are aware of Raman spectroscopy techniques in the study of molecules and materials. It has been a common technique in these areas of study for many, many years since its first proposal in.... get this.... 1929![1]

So already it is a very useful technique in chemistry and material science. But now it has found another application, in medical diagnostics. It turns out that this same technique can be used to find hard-to-detect skin cancer.[2]

Abstract: Melanoma is the most deadly form of skin cancer with a yearly global incidence over 232,000 patients. Individuals with fair skin and red hair exhibit the highest risk for developing melanoma, with evidence suggesting the red/blond pigment known as pheomelanin may elevate melanoma risk through both UV radiation-dependent and -independent mechanisms. Although the ability to identify, characterize, and monitor pheomelanin within skin is vital for improving our understanding of the underlying biology of these lesions, no tools exist for real-time, in vivo detection of the pigment. Here we show that the distribution of pheomelanin in cells and tissues can be visually characterized non-destructively and noninvasively in vivo with coherent anti-Stokes Raman scattering (CARS) microscopy, a label-free vibrational imaging technique. We validated our CARS imaging strategy in vitro to in vivo with synthetic pheomelanin, isolated melanocytes, and the Mc1re/e, red-haired mouse model. Nests of pheomelanotic melanocytes were observed in the red-haired animals, but not in the genetically matched Mc1re/e; Tyrc/c (“albino-red-haired”) mice. Importantly, samples from human amelanotic melanomas subjected to CARS imaging exhibited strong pheomelanotic signals. This is the first time, to our knowledge, that pheomelanin has been visualized and spatially localized in melanocytes, skin, and human amelanotic melanomas.

This is another example where experimental technique in physics EVENTUALLY finds applications elsewhere. I've highlighted other examples of this, with this being the most recent one before this post. Also note the "gestation" period between when this method was first proposed, and then when it became common in physics, to when it found other applications outside of its original main use. This is not new. Look at how long between when NMR became a common technique to when it evolved into MRI. Medical technology would not have evolved and advanced without a much earlier advancement in physics and physics experiments!

What I'm trying to emphasize here is that you may not feel the pain NOW when you cut funding to basic science research. But the pain WILL be felt later, by your children and grandchildren, because it takes years for what we work on now to become a useful technique elsewhere. That physics that we used to detect some esoteric particles that you don't care about may just one day be the diagnostic tool that saves someone's life!

Zz.

[1]C.V. Raman and K.S. Krishnan, The optical analog of the Compton effect, Nature 121, 711 (1928); G. Landsberg and L. Mandelstam, A novel effect of light scattering in crystals, Naturwissenschaften 16, 557 (1928); C.V. Raman and K.S. Khrishnan, The production of new radiations by light scattering, Proc. Roy. Soc. (London) 122, 23, (1929).
[2] H. Wang et al., Scientific Reports 6, Article number: 37986 (2016). Paper is open access.

Friday, March 03, 2017

The Laws Of Life

Physics Today has made the article "The Laws of Life" from the March 2017 issue available for free. In the article, astrobiologist Charles Cockell describes how the fundamental laws of physics influences the forms of life on Earth.

Zz.

Thursday, March 02, 2017

Online Homework Assignment - Are They Effective?

I read this news with a bit of interest. It appears that a student at Brooklyn College is gathering petition signatures to end the use of something called "Expert TA". This sounds like an online HW assignment that has been used by the physics department at that school.

Each homework assignment has about 15 to 20 questions, but each question has multiple parts. The number of questions, attempts, and credit reductions for wrong answers is dependent on the instructor. The instructor has the option to deduct points when a student accesses hints, and feedbacks. Expert TA consists of two types of feedback: Direct and Socratic. Direct feedback let’s a student know exactly what they did wrong, while a Socratic feedback poses a question such as “Have you considered the following?” Though this may sound quite useful, students feel otherwise.

It would be a bit more informative, and more persuasive, if a specific example on how this online tool is ineffective. For example, the best complaint that I can read from the report said this:

“The problem doesn’t lie in the concepts,” said Manasherov. “It’s more like how can we navigate this website and give the right answer—the right answer meaning what the website is looking for.”
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“The hints aren’t always helpful and the feedback isn’t always clear either,” said sophomore Melissa Beagle. “And they only give you a limited number of tries, which doesn’t really help.”

There types of comments are not really that informative. It is similar to you telling your doctor "I just don't feel right" without giving any specific description of what is wrong.

I have a bit of experience in dealing with such online HW assignment. I've written about it in an earlier blog post on here. In fact, I will also add that I actually worked though the online HW assignment that my students would be facing, and I can see and experience what they will have to go through. I can see good points and bad points about it. But as I've said in that earlier blog post, the biggest issue I have about online anything is the question on whether the student doing it had any external help. But that is an issue that would be present in the traditional, written HW assignment as well since the student can easily copy or had help in completing the assignment. Except for one major difference.

You see, traditional written HW assignment requires that the student show work in arriving at an answer. You normally do not see that with online assignment. From what I can gather when chatting with students, all they care about is getting the right answer to type into those answer boxes. Often time, their "work" in deriving the answer is either done haphazardly, or not as complete and clear as one that would be required in a written HW assignment that is being submitted for grading. So in some instances, these students really could not recall what they did right and what they did wrong.

I'm still divided on my opinion regarding this type of HW assignment. I see some value in it. It certainly makes the job of an instructor a bit easier. But I also see how this can make the student being lazy to really learn what is needed in solving a particular problem.

If you have gone through such online HW assignment, or if you're an instructor whose course use such a thing, I'd like to hear from you.

Zz.

Wednesday, March 01, 2017

Lenz's Law Is A "Quirk" Of Physics?

I've never heard of "fidget toys" before till after I read this piece. This one is describing a fidget toy that supposedly has "antigravity" effects that simulates the low gravitational field of the moon and Mars, making the object falls slower. The toy is called Moondrop.

Based around the principle of Lenz’s law — which *deep breath* states that the current induced in a circuit due to a change or motion in a magnetic field will create a field that opposes the charge that produced it — Moondrop is a gravity-defying fidget desk toy that imitates the differential gravitational free fall on Mars and the Moon.

OK, so immediately, there are two issues here:

1. Lenz's law is not a "quirk" of physics, as stated in the title of this report. In fact, it is quite a central phenomenon in physics that is responsible for power generators to create our household electricity! So how is that a "quirk"?

2. Any physics undergraduate can spot the error in the definition given for Lenz's law. Lenz's law is the effect whereby a magnetic field is generated to oppose the CHANGE in the external magnetic field. Maybe there is a typo in the definition given, that it should have been "change" instead of "charge". That one word (or in this case, one letter) change results in an astounding difference in the physics.

If I recall correctly, there are magnetic breaks that use the same principle. I remember reading something on roller coaster rides that made use of such magnetic breaks, so that it ensure that the vehicle can still be safely stopped even when the power goes off.

So the application of Lenz's law is neither that highly unusual, nor is it a quirk of physics.

Or maybe the writer meant a "quark" of physics?

Zz.

Monday, February 27, 2017

Mildred Dresselhaus In GE Commercial

So, if you did watch the 2017 Academy Awards last night and didn't run away during the commercials (at least here in the US), you may have seen the GE commercial to celebrate women in science that featured the late Millie Dresselhaus. She, of course, passed away on Feb 20, so this commercial has become a tribute to her and left a legacy to encourage women to enter science, and physics in particular.

In the commercial, GE asks what it would be like if we treated women scientists like celebrities and deserving of the accolades and recognition like any pop celebrities.

If you missed it, here's the commercial once again:



Zz.

Friday, February 24, 2017

SRF Technology For Particle Accelerator

Here's a brief video on the superconducting radiofrequency (SRF) cavity for particle accelerators.



I wouldn't call it "better particle accelerator" as in the video, because SRF cavity with Nb currently have a limit of 20-30 MV/m gradient, whereas normal conducting cavity can reach 100 MV/m or even higher at 1.3 GHz.

Still, these SRF cavities have properties that are "better" in other characteristics, especially in the Q-value. And in a number of applications, these cavities are the most efficient accelerating structures.

The technology for SRF is still evolving, especially in whether there is a need for superconducting photocathode sources for SRF guns. So there's a lot more to do in this field of study, both in terms of the physics, and in engineering.

Zz.

Wednesday, February 22, 2017

Dark Energy - What Is It?

I've posted many articles on Dark Energy. But here's another one aimed at the general public that actually is quite instructive. It describes not only why we think there is dark energy, but also the puzzling phenomenon of the apparent "switching" between one regime to another.

Please take note that, while it seems that this idea has been floating around for a while, the study of Dark Energy is very much still in its infancy. The general public may find it hard to understand, but we really do need a lot more experimental observations on this, and that is easier said than done. Detection of this is not easy and requires years of design and work, and not to mention, funding!

Zz.

Mildred Dresselhaus

An absolute giant in physics, and especially on condensed matter physics, Mildred Dresselhaus passed away recently at the age of 86.

Besides all of her accomplishments in physics, she was truly a trail-blazer for women in science, and in physics in particular with all of her "firsts". She, along with Vera Rubin and Deborah Jin, were the strongest candidates to break the drought of women winning the Nobel Prize in physics. Now we have lost all three.

Zz.

Monday, February 20, 2017

Will SMASH Be A Smash?

Here comes a new extension to the Standard Model!

A new theoretical paper in PRL has extended the Standard Model of elementary particles to include new particles, and tries to mash different ideas and theories into this new standard model called SMASH - Standard Model Axion See-saw Higgs portal inflation (yeah, it's a mouthful).

SMASH adds six new particles to the seventeen fundamental particles of the standard model. The particles are three heavy right-handed neutrinos, a color triplet fermion, a particle called rho that both gives mass to the right-handed neutrinos and drives cosmic inflation together with the Higgs boson, and an axion, which is a promising dark matter candidate. With these six particles, SMASH does five things: produces the matter–antimatter imbalance in the Universe; creates the mysterious tiny masses of the known left-handed neutrinos; explains an unusual symmetry of the strong interaction that binds quarks in nuclei; accounts for the origin of dark matter; and explains inflation.

Of course, with ANY theoretical ideas, which often has long gestation period, a lot of patient waiting and testing will have to be done to verify many of its predictions. But this seems to create quite an excitement in revamping the Standard Model.

Zz.


Friday, February 10, 2017

Politics And How It Affects US Physics Research

This is a very poignant article on how politics have impacted Physics research in the US for the past decade or so. Reading this can be very disheartening, so be forewarned!

The one impact that I had mentioned a few years ago is also mentioned here, and that had to do with not only the impact of budget cuts, but also the devastating impact of a budget cut AFTER several months of continuing resolution of the US budget.

I remember one year on December first, we had a faculty meeting where we heard funding levels would be up 10% across the board — a miraculous state of affairs after multiple years of flat-flat budgets (meaning no budgetary increases for cost of living adjustments — which ultimately means it’s a 3% cut). At our next faculty meeting on December fifteenth, we heard that it was going to be a flat-flat year — par for the course. On December nineteenth, we hear the news that there was a 30% cut in funding levels.

Now losing 30% of your budget is very bad in all circumstances, but you have to remember that the fiscal year begins on October first. The only thing you can do is fire people since all the funding is salaries and to do that legally takes about six weeks and with the holiday shutdown, that meant that this was a 50% cut in that year’s funding. There was some carry-forward and other budgetary manipulations, but 30% of the lab was lost, about three or four hundred if I recall. The lab tried to shield career scientists and engineers, but still many dozens were let go.

In a post from a few years ago, I showed the simple mathematics on why this effect is devastating for science research.

Unfortunately, I don't see this changing anytime soon. As the author of this article wrote, science in general does not have a "constituent". No politician pays a political price for not funding science, or wanting funding for science to be cut, unlike cutting funding for social programs, military, or other entitlements.

Regardless of who is in office or who is in control of the US Congress, it is business as usual.

Zz.

Wednesday, February 08, 2017

Gamma-Ray Imaging At Fukushima Plant

I mentioned earlier of the muon tomography imaging that was done at the damaged reactor at Fukushima, and tried to highlight this as an example of an application that came out of high energy physics. This time a gamma-ray imaging spectroscopy was performed at the same location to pin-point contamination sites.

But as with the muon tomography case, I want to highlight an important fact that many people might miss.

To address these issues of existing methods and visualize the Cs contamination, we have developed and employed an Electron-Tracking Compton Camera (ETCC). ETCCs were originally developed to observe nuclear gammas from celestial objects in MeV astronomy, but have been applied in wider  fields, including medical imaging and environmental monitoring.

So now we have an example of a device that was first developed for astronomical observation, but has found applications elsewhere.

This is extremely important to keep in mind. Experimental physics often pushes the boundaries of technology. We need better detectors, more sensitive devices, better handling of huge amount of data very quickly, etc...etc. Hardware have to be developed to do all this, and the technology from these scientific experiments often trickle down other applications. Look at all of medical technology, which practically owes everything to physics.

This impact from physics must be repeated over and over again to the public, because a significant majority of them are ignorant of it. It is why I will continue to pick out application like this and highlight it in case it is missed.

Zz.

Tuesday, February 07, 2017

Being Slowly Eaten For A Decade

This is the definition of the ultimate torture.

It appears that this black hole has been slowly feasting on this dead star for at least a decade. Ouch!

"We have witnessed a star's spectacular and prolonged demise," said Dacheng Lin, a research scientist at UNH's Space Science Center and the study's lead author. "Dozens of these so-called tidal disruption events have been detected since the 1990s, but none that remained bright for nearly as long as this one."

The arXiv version of this paper can be found here.

Moral of the story: Never piss off a black hole!

Zz.

Monday, February 06, 2017

Photons Steal Momentum From Sun's Surface?

We all know that photons carry momentum. But who knew that photons leaving the sun's surface actually may cause the varying rotation of the sun with its radius?

This new paper from PRL makes the confirmation that the sun's surface has a greater drag and a slower angular rotation than the deeper part of the sun. But not only that, it also proposes that this slowdown is due to the loss of momentum when photons are emitted from the plasma on the surface.
Kuhn and his colleagues also developed a model to explain their data. Photons are created in the Sun’s dense core, where the plasma behaves nearly like a solid. As they diffuse outward, they experience plasma that is less dense, faster flowing, and subject to turbulent convection. As the photons interact with the moving plasma, they exchange angular momentum with it. Inside the Sun, the photons scatter so frequently that they lose as much angular momentum as they gain. But in the photosphere, where photons escape the Sun, the plasma-photon momentum transfer results in a net loss of the plasma’s angular momentum, as photons radiate away. The effect on the plasma is a mild braking force, which slows its overall rotation. This braking is most effective at the outer edge of the Sun, where the plasma density is at its lowest.
Those photons! They can create havoc!

Zz.

Thursday, February 02, 2017

The Emperor Has No Clothes

The impact of the Trump's executive order on the admission of citizens from the 7 countries continues to be felt and the topic of conversation in many college campuses, science labs, and conferences. But something triggered in my head when I read this Washington Post news article on how this ban would not have prevented the attacks in the US since Sept. 11. When I read this, I immediately remembered a similar scenario, and this is where I connect it to the theme of this blog.

Back in, oh, I forget exactly when, probably mid-2000s, there was a laser accident at a lab (I'm not gonna name names). I'm going to rely on my memory based on what I read as the official report on the accident, and from what I heard from a friend who happened to know the person involved.

To set up the scenario, most, if not the majority, of laser accident occurred when the laser is running and the safety mode is bypassed. The most frequent reason for doing this is that the laser is either being worked on, being repaired, being serviced, or the most common occurrence, it is being aligned. People who are authorized to do this are usually trained, and had to undergo safety classes to ensure that they know what they are doing.

What happened in this accident, from what I remember, is that this person, along with at least one other person, was doing a typical laser alignment. He was wearing a pair of safety glasses as required, which protected his eyes in case there were stray beam hitting his face. Unfortunately, while in the middle of doing this work (which was part of the standard operating procedure of the facility), he had an itch around his eyes. In a moment where instinct took over, before he had time to think about it, he reached inside his safety glasses with his hand to rub his eyes, causing the safety glasses to be lifted off his face. Unfortunately, without realizing it, a beam of the laserwas, at that time, pointing straight at him. It only happened probably less than a second, but it was enough that the laser hit his eyes and sufficient to cause damage.

I'm not going to go into detail of what happened immediately afterwards, because it isn't relevant to this story. So of course, after this incident is reported, the lab issued a lab-wide stand-down, and all operations of Class 2b laser and higher had to stop. We were told to evaluate our laser operations and safety procedure, and we had to get reauthorized before we can continue work. At the same time, all personnel that are involved in any laser work had to attend a safety seminar.

So I sat through this safety seminar where they described the accident, emphasize the need for us to work safely, re-enforce the requirements for safety procedure... etc...etc. But at the same time, in response to the accident, they produced a whole new set of policy and procedures for all laser facilities. We had to have yearly inspection, yearly authorization, and new documentation of our procedure and safety analysis. In other words, new set of administrative controls were introduced.

Of course, as you can guess, there were groans in the audience, because it meant that there would be more bureaucratic paperwork and administrative hoops that we had to go through. During the Q&A session, several people asked questions, and one could tell that a lot of people in the audience weren't too pleased by this. Finally, and this is where I came, in, I raised my hand, and asked something like this:

"So how would any of the new procedures that were introduced prevented this accident?"

Now, looking back on it afterwards, I would describe the audience reaction to my question as what I imagined would happen when someone finally yelled that the Emperor had no clothes. In this case, the Emperor truly had no clothes. It was an unfortunate accident, but no amount of training, regulation, safety briefing, paperwork, review, etc. would have prevented it, because that was something instinctual. The new administrative policy that was put in place didn't make any of us who work with these lasers any safer. I certainly didn't feel any safer than before. Yet, this was imposed upon us. It wasn't to make us any safer or to prevent any accident. It is simply to placate the higher-ups, the stakeholders, the policy makers, the regulators, the administrators, and finally and ultimately, the politicians (if they decided to look into this). They can say that they implemented this and that after the accident to make them look good. The rest of us who are actually doing the work get saddled with more paperwork and more hoops to jump through.

I'm certain that this isn't new, and that many people have gone through such similar situations where what is being done in the name of something really isn't effective and may miss the mark. Often times, we simply go along just to make the administration happy so that we can move on and continue with our work. But it still means that the Emperor has no clothes, and sometime, someone really needs to stand up and points out this ridiculousness.

Zz.