Monday, June 30, 2014

"Proof" of Pilot Waves from Fluid Dynamics?

This Wired article seems to indicate that the evidence for the validation of Bohmian's "Pilot Wave" idea for quantum mechanics can be found in some fluid dynamics experiment.

In a groundbreaking experiment, the Paris researchers used the droplet setup to demonstrate single- and double-slit interference. They discovered that when a droplet bounces toward a pair of openings in a damlike barrier, it passes through only one slit or the other, while the pilot wave passes through both. Repeated trials show that the overlapping wavefronts of the pilot wave steer the droplets to certain places and never to locations in between — an apparent replication of the interference pattern in the quantum double-slit experiment that Feynman described as “impossible … to explain in any classical way.” And just as measuring the trajectories of particles seems to “collapse” their simultaneous realities, disturbing the pilot wave in the bouncing-droplet experiment destroys the interference pattern.

Droplets can also seem to “tunnel” through barriers, orbit each other in stable “bound states,” and exhibit properties analogous to quantum spin and electromagnetic attraction. When confined to circular areas called corrals, they form concentric rings analogous to the standing waves generated by electrons in quantum corrals. They even annihilate with subsurface bubbles, an effect reminiscent of the mutual destruction of matter and antimatter particles.

OK, let's be VERY clear on this, shall we? In this experiment, there is a very important feature here that needs to be  pointed out. We can DETECT these "pilot waves" that are steering these droplets. This is a very, VERY, important point here. In QM, these pilot waves have NEVER, EVER, been detected. That is a very significant difference, and the main factor why the pilot-wave model hasn't caught on! Trust me, if there's physical evidence for it, physicists WILL adapt it! As of now, there are no deviations between the predictions of the conventional QM versus the pilot-wave picture. So how can one tell which one to accept beyond just a matter of taste and personal preferences?!

The other thing that needs to be pointed out is that this is, at best, an ANALOGOUS situation to the pilot-wave picture. It is NOT an identical situation. The "discovery" of magnetic monopole in the spin-ice system did not turn elementary particle and EM upside down, because while these "monopoles" sure have the same characteristics of the bare monopoles, they are, at best, only analogous to them. These are still NOT what we are looking for! It is not the same thing.

Until there is direct evidence of such pilot wave, or until there is evidence that support the prediction of pilot-wave but not the regular, conventional QM picture, then we have no strong evidence to support or falsify one or the other. Period. It is irrelevant how many droplets and wave experiments one performs.


Economist's Article On "Neutrinos" Is Still Inaccurate

I applaud when news organization such as The Economist decides to give science some coverage. It is important because such magazine reaches out to an audience that many science journals and magazines do not usually get. So this criticism is not a knock on their science coverage and hopefully, will not discourage more of it on their pages.

Still, I find it very hard to accept that an article in a magazine as popular and prestigious as The Economist would not have had some sort of expert proof-reading before it is published. They can afford to at least hire a free-lance consultant to make sure there are any obvious errors or inaccuracies in such articles (I'm available!). Take this article on the neutrinos, for example, that Business Insider took from The Economist. There are minor quibbles here and there, but there are a couple of points in which someone who doesn't know much of the topic would have a very misleading or wrong idea about what is going on.

The first is this one:

Stand in front of it and you are standing in the path of the most powerful beam of neutrinos in the world, which is emerging from a nearby particle accelerator at Fermilab, America's main particle-physics laboratory.

With any other kind of accelerator, standing in the beam would have spectacular and fatal consequences. But your correspondent was not vapourised--nor, several weeks later, has he developed either cancer or superpowers.

Well, actually, you WILL die, because the "particles" in the accelerator are not neutrinos but rather, in this case, protons! That quoted passage made it sounds as if the neutrinos are the ones being directed by the accelerator. They are not. In fact, one doesn't control the path of neutrinos whatsoever once they are generated. So kids, if you think you can stand in the path of the particles generated in these accelerators, banish that thought!

The other one is a bit more severe:

But the details of oscillation remain incomplete, which is where Fermilab's neutrino beam comes in. By the end of July work should have finished on building NOVA, an experiment designed to pin those details down. The beam that passes through the white circle will carry on for 810km (500 miles) through the Earth to a detector in northern Minnesota. When it arrives, some of the muon neutrinos in it will have transformed themselves into electron neutrinos. NOVA will measure precisely how often this occurs.

This mistake is consistent with the previous one. The writer is still thinking that the neutrinos are the ones being accelerated, because if you read this, it somehow implied that these neutrinos go around the "white circle", and then proceed 810 km away to northern Minnesota. This, of course, is wrong. Protons in the main injector (the "white circle") are bombarded onto a target. The resultant is a bunch of particles, including muons. These muons then will decay rather quickly, and one of the decay products is a neutrino! These are the neutrinos that will shoot off to northern Minnesota. There are variation to such process, but the principles are similar. You do not start off with these neutrinos, accelerate them in the particle accelerator, and then shoot them off. There are just simply no way to do that!

I don't understand why magazines such as this do not seek an expert to do copy-reading to ensure the accuracy of these types of articles. Maybe most of the readers can't tell that there are inaccuracies, and those who do, seldom point them out. It is obvious that this method hasn't ruined their reputation or they would have done something.


Thursday, June 26, 2014

The Story Of Neutrinos

If you still need another exposition on neutrinos and why they are so important, then you might want to listen to this podcast by astronomer Ray Jayawardhana.

If already supplied several resources at various levels in this blog for those of you who need more info on these elusive particles. So just do a search.


Wednesday, June 25, 2014

Going Around In Full Circle

I guess I am old enough to sometime look back on my career and be amazed how it has turned out. At this point, I think I've gone a full circle and coming back almost to where I started.

When I was doing my PhD research, it was in superconductivity. I was doing experiments on tunneling spectroscopy of high-Tc superconductors. Then I moved and did my postdoc in photoemission spectroscopy, and a large portion of the material that I studied were superconductors as well. Next, I switched careers and went into accelerator physics and learned a whole new field of study in physics. Eventually, I found my niche and went to study and make photocathodes for accelerators, which made used of my knowledge and skills from my photoemission work.

And now, things have come full circle. I've started work on studying and producing superconducting photocathodes for superconducting RF guns. I've gone back to the first area of study that I started. Although, I must admit that this study utilizes my knowledge from both areas that I've specialized in. So I'm actually rather excited to go into this.

Still, it is funny how life takes you on your journey.


Friday, June 20, 2014

The Problem With Doing Science Via Public Media

OK, so it is not really doing science via public media, but we all should have learned our lessons already by now when new results are announced via press conference AHEAD of it being scrutinized by experts in the field. We could go back, way back, to the Fleshmann and Pons "cold fusion" debacle. But people young enough to not be aware of that still have no excuses, because the recent "fast than light" neutrinos measured by OPERA should also be a major lesson.

But I guess some people, especially the PR departments at major institutions, just never learn. The same embarrassing fate may befallen on the recent BICEP2 results. After much media publicity of the implications of the results, the media are now touting how it could be wrong, which is a claim that needs to also be verified.

I can certainly understand how "big discoveries" of this magnitude can being a spotlight to science, especially in physics. I definitely see the advantage of that. However, and this is especially true for something that is so dependent on many factors and many ways to analyze, we need to lean on the conservative side and let the process takes its course before touting the results. I am certain that if the BICEP2 result was simply submitted for publication, and then it appears in print, no one in the media would somehow recognize the profound implication of its results. So why not wait until sufficient scrutiny has been done before we approach the media and then tell them that, hey, we have published this paper and this is the big implication of the result?

This is where the news embargo that Science and Nature impose on submission inadvertently helps in this process. Unlike PRL and many journals that do not have such restrictions, Nature and Science forces the authors to "keep it down" while the manuscript undergoes its rounds of scrutiny and refereeing, no press releases, no public announcement, etc., until after it has been accepted. Then, even the PR people at these journals will try to trumpet the results as much as they can!

You do science via public media, you sometime die via the same public media.


Thursday, June 19, 2014

BICEP2 Results Are Published

With much brouhaha, and with a lot of skepticism, the news-making results and conclusions from BICEP2 is now published in PRL.

This comes on the heel of several high-profile criticism of the analysis, the most prominent of which is the preprint appearing on ArXiv that deduced a possible flaw in BICEP2 analysis.

As with anything, and especially something as difficult as this that requires a lot of analysis and assumptions, the rest of us just need to sit back, let the experts work this out, and be patient for more observations to come in. This will not be settled anytime soon.


Thursday, June 12, 2014

Extra Dimensions

Here's a video on the idea of extra dimensions and the possible link to why gravity is so weak.


Saturday, June 07, 2014

Logical fallacy poster

Thanks to Greg at Physics Forums for finding the link.

I think a lot of people (especially politicians, TV talking heads, and crackpots) should download , read, and understand this poster. :)

But then again, why should they?


Wednesday, June 04, 2014

European Spallation Source

This is an article on the ESS, currently under construction in Lund, Sweden. This facility, when finished, will rival the Spallation Neutron Source at Oak Ridge, Tennessee.

I'm highlighting this because not many people are aware of the use of neutrons as a device to study other things. The article mentioned two different types of neutron source facilities (reactor and spallation), and also a paragraph on the usefulness of neutrons as a tool:

Neutrons have properties that make them indispensable as tools in modern research. They have wavelengths and energies such that objects can be studied with a spatial resolution between 10–10 m and 10–2 m, and with a time resolution between 10–12 s and 1 s. These length- and time-scales are relevant for dynamic processes in bio-molecules, pharmaceuticals, polymers, catalysts and many types of condensed matter. In addition, neutrons interact quite weakly with matter, so they can penetrate large objects, allowing the study of materials surrounded by vacuum chambers, cryostats, magnets or other experimental equipment. Moreover, in contrast to the scattering of light, neutrons interact with atomic nuclei, so that neutron scattering is sensitive to isotope effects. As an extra bonus, neutrons also have a magnetic moment, which makes them a unique probe for investigations of magnetism.

I had linked a while back on a very good article on the usefulness of neutrons, which is often overlooked.


Monday, June 02, 2014

Just Because A Lot Of Things Are Mysterious, That Doesn't Mean They Are Connected

It looks like I am not the only one who is frustrated by the likes of Michio Kaku and Deepak Chopra when they delve into something that they have little knowledge about. This "rant" is almost on points as far as pointing out the ridiculousness of someone who delve into an area that he/she has little knowledge in and thinks that he/she has formulated a meaningful idea.

I hold degrees in physics and have spent a lot of time learning and teaching quantum mechanics. Nonphysicists seem to have the impression that quantum physics is really esoteric, with those who study it spending their time debating the nature of reality. In truth, most of a quantum mechanics class is lots and lots of math, in the service of using a particle’s quantum state—the bundle of physical properties such as position, energy, spin, and the like—to describe the outcomes of experiments. Sure, there’s some weird stuff and it’s fun to talk about, but quantum mechanics is aimed at being practical (ideally, at least).

Yet the mysterious aspects of quantum physics and consciousness have inspired many people to speculate freely. The worst offenders will even say that because we don’t fully understand either field, they must be related problems. It sounds good at first: We don’t know exactly how some things in quantum physics work, we don’t know exactly how to go from the brain to consciousness, so maybe consciousness is quantum.

The problem with this idea? It’s almost certainly wrong.

Just do a search on Deepak Chopra or my rant on The Secret book on here and you'll see my similar argument.

The essay also took shots at physicists who dipped their toes into areas that they had very little expertise in.

Some of them think that the overwhelming success of modern physics gives them the ability to pronounce judgment on other sciences, from linguistics to paleontology. Celebrity physicist Michio Kaku is a particularly egregious example, getting evolution completely wrong (see this critique) and telling infamous crackpot Deepak Chopra that our actions can have effects in distant galaxies. Then there are the physicists—including Freeman Dyson, one of the architects of the quantum theory describing interactions between light and matter—who contradict climate scientists in their own area of expertise.

The take-home message is contained in the very last paragraph, which I strongly endorse.

The problem with Klemm’s assertions, as well as those of many others who misuse the word quantum, is that their speculation is based on a superficial understanding of one or both fields. Physics may or may not have anything informative to say about consciousness, but you won’t make any progress in that direction without knowing a lot about both quantum physics and how brains work. Skimping on either of those will lead to nonsense.

You can take that, and substitute it with any particular knowledge, and you'll have a very respectable way of living a life. One can argue that a lot of the major political and societal problems that we face are due to people who make decisions and arrive at conclusions based on incomplete or faulty knowledge of a particular matter.


A Disappointingly Weak Case Made For HEP Funding

When I came across this blog entry in Huff Post by a high-energy physicist, I thought, "Oh good! Someone is going to make a good case to the public on why they, and the politicians, should not make funding cuts to HEP". I was sadly disappointed after a rather weak essay made to argue for its support. The basic argument was made in the very last paragraph:

I encourage you to find out more about the exciting science to be done. I hope that after this significant planning exercise, our field will be able to make the case that we are good stewards of the public money, have an exciting program that benefits humanity, and will receive more positive news from the budgets to come.

In other words, fund us because we do good and important science.

Unfortunately, in this day and age, such a thing just doesn't work, or is not that convincing anymore. In fact, I think in the few essays on this that I've written on my blog, I had made a more convincing arguments on why HEP funding is NECESSARY, and I'm not even in HEP!

Whenever someone from an esoteric field such as HEP, Astrophysics, etc.. tries to make a point on why it is necessary to fund such a field, there must be several different types of argument to be made when it is pitched to non-specialists/scientists:

1. Pitch the science, i.e. what are you trying to do.

2. Argue why basic knowledge, even when there seems to be no obvious application or benefit to mankind, is necessary, based on history.

3. Argue why the process of studying these things, especially in experiments done, had produced numerous "by products" that are now ubiquitous in our lives. So even areas that may not have any immediate applications from the knowledge, have produced many immediate applications just from the pursuit of studying these things.

4. Present the percentage of money being spent in perspective, i.e. look how how minuscule the funding for HEP in DOE's Office of Science, for example, when compared with the funding levels of other fields and when compared to the cost of a single stealth bomber. You cannot just present a number to the public without putting in some context and perspective. After all, to many (all?) of us, US$750 million is a lot of money! But is it a lot when compared to the overall funding picture and the costs of many of the things being paid out of the US budget?

Based on my interactions with many of the members of the public for many years, both in person and online, these are the four main points that I have found to be effective in convincing many to fund these areas that are very hard to argue for based on the nature of the subject matter. I don't have to argue that hard to convince the public on why funding the study of semiconductors or quantum computation is necessary. They can already figure out the potential applications of these things. Arguing why they need to fund the search for the Higgs require a lot more effort, and a lot more careful thought than just to argue that it is a necessary step in the intellectual process, or that we need to cater to our curiosity. A lot of people are curious, yet they don't seek millions of dollars of public funding to satisfy those curiosities. You need to make a careful, thoughtful, and convincing argument on why support such a thing is important in a number of ways, and how previous fundings of such areas have impacted our lives.

Make it so that they should care!