The reactionless thruster known as the EmDrive is back in the news. This time the buzz arises from a new theoretical paper that attempts to explain just how the device can seem to violate basic physics. While this new work begins with some basic quantum physics, it quickly veers into uncharted (and highly speculative) theoretical waters to achieve its goal. 

The EmDrive is highly controversial because it is claimed to create a thrust without a corresponding propellant. Such a “reactionless drive” would violate Newton’s third law of motion, which is one of the basic tenets of classical physics. Usually this kind of thing is quickly tossed onto the compost pile of fringe science, but in this case several independent groups have claimed to observe a thrust from this kind of device. While this might seem like solid evidence, there are several reasons to be skeptical. To begin with, none of the work has yet been peer reviewed. It was announced last month that some of the experimental work is currently undergoing peer review, but no peer-reviewed paper has yet appeared. This is important because the supposedly observed thrust are extremely small, and it is notoriously difficult to rule out more mundane causes for these kinds of odd tiny effects. Secondly, if the EmDrive actually works, it would violate known physics. There is currently no theoretical explanation for why such a thrust might occur. While you don’t need a theoretical explanation for a clear experimental result, it would help to have a theoretical model one could test. This new work attempts to create such a theoretical model.

The model begins with an idea out of quantum physics known as the Unruh effect. In quantum theory, empty space can be described as being filled with a quantum field. A vacuum, in this view, is simply the lowest possible energy state for these fields. For an inertial observer (one that isn’t accelerating) this field has effectively zero energy, and empty space looks like a vacuum just as we’d expect. However, for an accelerating observer the field has an observed energy, and the observer would observe a sea of particles in thermal equilibrium. As a result, an accelerating observer would be heated by quantum particles. While this might seem odd, it’s actually a well known effect, and is somewhat similar to Hawking radiation. While the Unruh effect isn’t controversial, it’s never been observed because it is such an extremely tiny effect. An acceleration of a trillion gees would create a temperature of less than a millionth of a Kelvin. The Unruh effect raises an interesting question for accelerating particles, specifically whether an accelerating particle interacting with an Unruh thermal background will emit radiation that can be observed by a non-accelerating observer. This would be known as Unruh radiation, and there are theoretical models both for and against it. While it seems reasonable that Unruh radiation should exist, it’s also reasonable to be skeptical.

In the theoretical model for the EmDrive, it’s assumed that Unruh radiation is real. Furthermore, the author of the model argues that Unruh radiation is the source of inertia. The basic idea is that an accelerating mass would experience a kind of drag due to the Unruh effect, which we describe as the inertial resistance to acceleration seen in classical physics. This effect would be largely indistinguishable from the usual behavior of inertia, but the author argues that subtle differences would show up as anomalies, such as the flyby anomaly seen in some spacecraft. From there it gets even more speculative, because the author claims that photons can also have inertial mass due to the Unruh effect, and thus give the EmDrive a reactionless thrust.

The overall shape of the EmDrive is somewhat conical. As electromagnetic radiation is is bounced around in this conical cavity, the allowed energy levels of photons at the narrow end are slightly different from the allowed energy levels at the wider end. So photons can transition between energy levels within the cavity of the device. In the model, photons at different energy levels have different inertial mass. So when photons transition from higher energy levels at the narrow end to lower energy at the wider end, their inertia changes. By Newton’s third law, there must be a reaction force on the drive itself. In short, this model buries Newton’s third law in quantum speculation. Through this model the EmDrive can defy Newton’s law by thrusting against the vacuum of space rather than violating the law directly.

In its defense the work does at least strive to make clear and testable predictions. Not only does it predict discrete levels of thrust based upon the geometry of the cavity, it also predicts that one should see a reversal of thrust direction given a cavity of certain dimensions. But it also isn’t something to get too excited about. This new work doesn’t prove the effect is real. It does not even agree with claimed results that strongly. The model also raises further theoretical problems, such as requiring that the speed of light changes within the cavity, which would violate the central property of special relativity. Even if the EmDrive works as this model claims, it still violates well tested laws of physics.

In all honesty I’d love to see a device like this actually work, but I’m not convinced the effect is real. While this new work is interesting, it doesn’t make the effect more convincing.

Paper: M.E. McCulloch. Testing quantised inertia on the emdrive. arXiv:1604.03449 [physics.gen-ph] (2016)

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Our Sun emits solar flares on a regular basis, but what would happen if it released a flare 100,000 times more powerful than the largest flare in recorded history? Could it destroy our power grid, irreversibly change life on Earth, or even strip the atmosphere from our planet? Let the fear-mongering begin! 

Superflares are in the news, and with it comes wild claims about their possible threat to human civilization. As with most hyped stories, they focus on just how powerful one could be, and how it might disrupt human civilization rather than the actual science, which is unfortunate because the science is pretty interesting.  It’s based on recent work that looked at the flare activity of more than 5,000 Sun-like stars. What they found was that stars where superflares occur tend to have stronger magnetic fields than stars where superflares are less likely. This correlation between superflares and magnetic field strength suggests that superflares are produced by a mechanism similar to regular solar flares.

From solar observations we know that solar flares occur when magnetic field lines near the Sun’s surface “snap” into realignment. The Sun actually rotates differentially, meaning that its equator rotates a bit faster than its poles. As a result, over time the magnetic field at its surface wraps around the Sun a bit. When the magnetic field is twisted up, it can realign quickly, producing a solar flare. For stars with stronger magnetic fields, the resulting realignment has a tendency to be more severe, and thus large solar flares (superflares) are more likely. This work shows that superflares are not a different phenomena, but are solar flares on a larger scale. They also found that superflares can occur on stars with magnetic field strengths similar to the Sun. While superflares are much more likely on stars with strong magnetic fields, the team found that about 10% of the superflares they observed occurred on stars with magnetic fields on par or weaker than that of our Sun. From their observations, they estimate that a superflare could occur on the Sun about once every thousand years or so.

That said, if such a superflare were to occur today it wouldn’t end civilization as we know it. There is some evidence in tree ring data that small superflares might have occurred in 775 and 993 AD, with little effect on human society. In our modern world solar flares do pose some risk to satellites and our electrical power grid, but we have ways of limiting their effect. In a bad-case scenario we might have some infrastructure to rebuild, but it wouldn’t be an extinction-level event.

So there’s no need to worry. Just keep calm and science on.

Paper: Christoffer Karoff, et al. Observational evidence for enhanced magnetic activity of superflare stars. Nature Communications 7, Article number: 11058, doi:10.1038/ncomms11058 (2016)

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A new black hole model will not “break” relativity. Relativity works just fine, thank you very much, and no computer simulation of a five dimensional black hole will change that fact. So why are science headlines making such a claim? It all starts with a new paper in the Physical Review Letters that focuses on the cosmic censorship hypothesis.

A troublesome aspect of black holes in general relativity is that all of a black hole’s mass collapses down to a region of infinite density known as a singularity. Other models like classical electromagnetism also have singularities, but they tend to be more of a mathematical remnant we can deal with. In relativity, the gravity within a black hole becomes so strong that matter is inevitably compressed into a physical singularity. At that point relativity “breaks down” in that it simply can’t tell us what’s going on. All physical models “break down” when you have a physical singularity. This is nothing new, and doesn’t mean that relativity is wrong, simply that there is a limit to its usefulness as a model.

The general consensus about black hole singularities is that a more general quantum theory of gravity will address the issue, likely by eliminating singularities from the equation. But until then one work around is to note that a black hole’s singularity is enclosed by the event horizon. Since nothing can escape the event horizon of a black hole, the singularity is safely hidden from the universe, so we don’t really have to worry about it. This is known as the cosmic censorship conjecture. There are difficulties with this idea when it comes to quantum theory and the information paradox, but that’s another story. If a singularity weren’t hidden by the event horizon, then it would be a naked singularity, and the cosmic censorship conjecture would be violated. Computer simulations have shown that naked singularities can form according to general relativity, but the known examples require unusual ideal conditions that aren’t likely to happen in the real universe. So it’s generally thought that real black holes can’t have naked singularities.

This new work looks at black holes in a 5-dimensional version of relativity (rather than the usual 4-dimensional relativity of our universe). In 5D relativity black holes that aren’t spherical can form, and the paper looks specifically at torus-shaped black holes with a ring singularity in the middle. From computer simulations the team found that thin torus black holes could develop an instability in such a way that a naked singularity could form. Interesting work, but not earth-shattering news.

So to sum up, singularities in general relativity are a problem  (which we knew). Naked singularities can form under special situations (which we knew). Naked singularities can form in hypothetical 5D versions of relativity as well (not really surprising). Naturally the headlines read “New Model Breaks Relativity!”

(Facepalm)

Paper: Pau Figueras, et al. End Point of Black Ring Instabilities and the Weak Cosmic Censorship Conjecture. Phys. Rev. Lett. 116, 071102 (2016)  arXiv:1512.04532 [hep-th]

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You won’t believe what they’ve done this time.

If you’ve read this far, I want to be clear that the headline was linkbait. This post isn’t about some new transgression from IFLScience, but rather about why hype in science reporting is so harmful. For my regular readers I promise never to pull this kind of thing again. For those who have come because of the outrageous headline, hear me out.

If you’re not part of the solution, you’re part of the precipitate. Credit: Kim Martini

A few days ago I wrote a post callout out IFLScience for misrepresenting research on solar cycles. It created a bit of a firestorm, with lots of people defending the site’s use of linkbait headlines:

Who cares if they grab some attention with their headlines. They’re pulling people away from main stream media which is a good thing.

These science websites have to bring in the non-science-degreed people.

I don’t blame IFLscience for having the odd attention grabbing article/headline, anything that gets more people into science and away from celebrity obsession is a good thing.

Hypothetically, the word “sun spots,” “ice age,” and “science,” were used in a conversation between two adults whose lives probably very rarely revolve around this. They’ve gotten people into the discussion. I don’t care how.

There was also a great deal of accusation that I was being elitist by calling out IFLScience:

IFLScience isn’t a technical journal, and it’s not pretending to be. It’s trying to make science news accessible to the masses.

IFLS is not a scientific journal, and as a social media page it should not be held to the standards of a scientific journal, or even a scientific news source such as Scientific American.

The fact is IFLS isn’t a peer-reviewed scientific journal. It’s a science and entertainment site.

What I find most disheartening about these kinds of comments is how deeply they underestimate people’s intelligence. It reinforces a common misconception that science is only for “smart” people, and it isn’t relevant to most people’s lives. Neither of these are true. People don’t need to be coddled or lied to in order to interest them in science, they need to be engaged in a clear and honest way. Science isn’t perfect, but it is a deeply powerful method for gaining knowledge. The more knowledge we have about the universe, the more readily we can face the challenges ahead. Hyping results and misrepresenting research only serves to strengthen the argument that scientists don’t really know what they’re talking about. That’s why it’s anti-science, and that’s why I called IFLScience out. They can be a voice for good, but when they willfully mislead it is deeply harmful. The same is true for any site that misrepresents scientific research.

The main argument of those defending hyped and misleading headlines is that it starts a conversation. To them I would say use this to start a conversation. Feel free to share this post with your friends, but better yet write your own. We deserve better than hyped headlines to spark a discussion.

Note: The image for this post? It was created by Andy Brunning as seen on (you guessed it) IFLScience.

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I’ve been getting a number of questions about NASA’s supposed discovery of a warp drive engine, and I’ve been resisting writing about it. Partly because I’ve written about it before, and partly because of the difficulty in separating the facts from wild speculation. Unfortunately none of the results have been submitted to peer review, so there’s no clear summary of the work that one can point to. That also means it hasn’t been publicly vetted, which is absolutely vital for this kind of claim. It should also be stressed that NASA hasn’t said they’ve discovered warp drive. They haven’t said anything on the matter. The buzz is coming from discussions on a site called NASA Spaceflight, which is not affiliated with NASA. With that in mind, what seems to be the evidence one way or the other?

The discussion centers on a so-called “reactionless drive.” That is, a device that can produce a thrust without a corresponding propellant. The idea is extremely controversial, because such a device would violate Newton’s third law (of action-reaction) which is one of the foundational laws of physics. There are actually two devices that claim this effect. One is known as the EmDrive, developed by Roger J. Shawyer, and the other is the Cannae Drive, developed Guido Fetta. Both of these devices bounce radio waves inside a resonant chamber to create a reactionless drive. The buzz this time around seems to be about the EM drive.

About a year ago, an EM drive experiment found a thrust of about 50 micronewtons. This is an extraordinarily small force, less than the weight of a small snowflake, but it’s not zero. This experiment was performed at atmospheric pressure, so the effect could have easily been due to experimental error. For example, uneven heating across the device could cause the air around it to recoil with different energies, causing a net thrust. We see a similar effect with a Crookes radiometer. This year a similar experiment has been done in a vacuum (about 5 microtorr) and again measured a thrust of about 50 micronewtons. That basically eliminates the atmospheric effects, but there are other more technical effects that could still be producing a false positive. The experiment has also been done in different orientations, and there seems to be directionality to the thrust. That would seem to work against the idea that the device is somehow coupling to the Earth’s magnetic field.

There has also been a basic experiment where a Michelson interferometer was placed next to the device. In principle, such a device could measure any variation of spacetime near the device. The results are supposedly consistent with the theoretical warping of an Alcubierre drive effect (which is a theoretical warp drive). What “consistent with” actually means is unclear, but that’s why so many popular articles are claiming “NASA accidentally discovers warp drive!” No scientist is actually claiming that.

On the face of it, this might seem pretty promising. A thrust has been observed, it seems to work in a vacuum, and there are hints of a warp effect. Here’s why we shouldn’t plan a party just yet. To begin with, one does not simply violate a fundamental law of physics. There are several ideas proposed to explain the thrust as a real effect, but they all involve a violation of basic physics. If this device is real, then Newton’s third law will have to be either thrown out or seriously revised. That by itself doesn’t mean the effect is false, since in the end the evidence wins. But history shows that long established scientific principles are very robust. I don’t doubt that the teams working on these devices are in earnest, but it is frustratingly difficult to account for all extraneous effects, particularly with such a small result. More than one scientist has thought they were on to something that didn’t pan out.

Which brings me back to my original statement that the work hasn’t been submitted to peer review. Much of it is hearsay based on discussion groups. While I’ve tried to present an even-handed summary, all of this should be read with an extremely skeptical eye. Both the EM drive and Cannae drive fans are claiming a violation of basic physics. Extraordinary claims require extraordinary evidence, and the threshold of evidence hasn’t remotely been reached yet. Is it interesting? Sure. Is it valid? We have no idea (but lots of reasons to doubt), and until formal evidence is submitted to peer review there is no reason to assume it’s real.

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There’s something strange about fast radio bursts, but they are not a message from aliens.

A fast radio burst (FRB) is a short, intense pulses of radio energy that have all the hallmarks of being astronomical in origin. Initially they were only detected at the Parkes radio telescope in Australia, which would make some kind of terrestrial origin likely. Later an FRB was detected at the Arecibo observatory in Puerto Rico, which made in more likely to originate from space. Earlier this year an FRB was detected in real time by multiple telescopes across the globe, which pretty much confirmed the origin as beyond Earth.

The FRBs seem to have discrete dispersion measures

One of the hallmarks of their astronomical origin their spectrum is dispersed. That is, instead of being a simple burst with all different frequencies happening at once, the frequencies were spread out, with higher frequencies first and lower ones later. This whistler effect is characteristic of a pulse that has traveled through the interstellar medium. It occurs because when an electromagnetic pulse interacts with charged ions, different frequencies are slowed by different amounts, with the lower frequencies slowed down more. So you get a dispersion effect. Stray bursts or chirps from terrestrial sources generally don’t have the same dispersion because they don’t travel through plasma and they don’t travel far. The time between the arrival of the high and low frequencies can be used to calculate the dispersion measure. Since the greater the dispersion measure, the more gas and dust the signal has travelled through, it is a good way to estimate the distance of the source.

This is where FRBs start to get really weird. It turns out the dispersion measure of these fast radio bursts seem to occur in multiples of 187.5 pc/cm³. Since the dispersion measures put the distances to these FRBs as billions of light years away, that would imply that their distances are evenly spaced across the universe, which isn’t likely for a natural phenomenon. A more likely solution is that they are much closer and originate within the Milky Way. The dispersion we observe would then be due to some unknown process rather than interstellar medium. This new process would need to have some mechanism to account for the discrete dispersions. That by itself would be extremely interesting, since it would demonstrate that dispersion can occur at the source as well as through interstellar interactions.

There is another aspect of these FRBs that’s interesting, and would imply an even closer origin. It turns out that their timing is very suspicious. They always occur within a tenth of a second of an official integer second in UTC (coordinated universal time). That’s really suspicious for something supposedly interstellar in origin, and would point toward something like stray signals from mobile phone towers and the like. Were I a betting man, I’d place my money on the terrestrial horse.

It should be emphasized that while this is interesting, it is an analysis of only 11 data points. We’ve only detected a handful of FRBs, and until we detect many more any speculation on patterns and origins should be made cautiously. Unfortunately most of the headlines want to spin the idea that since they appear both cosmic in origin and discretely spaced FRBs could be caused by some extraterrestrial intelligence. But going directly from “we don’t know” to “therefore aliens” is the realm of science fiction and hack journalism, not science.

Paper: Michael Hippke, et al. Discrete steps in dispersion measures of Fast Radio Bursts. arXiv:1503.05245 [astro-ph.HE] (2015)

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There’s been some buzz in the news about how the Large Hadron Collider (LHC) might disprove the big bang by discovering rainbow gravity. It certainly makes for a catchy headline, but the big bang is an observational fact, regardless of whether there was a primordial singularity. No experiment the LHC is planning will disprove the big bang. The term “rainbow gravity” might seem like the most hyped aspect of these recent headlines, but actually it’s just a funny name for a somewhat interesting idea.

Rainbow gravity is one aspect of an approach to quantum gravity known as the principle of general locality. In Newton’s relativity, motion is relative, but all events are set against an absolute background space and time. In other words, all observers agree on the time and place of a particular event. In Einstein’s relativity this isn’t the case. There is no absolute spacetime framework, so different observers will disagree on things such as how long a particular event takes, or even which of two events occurred first. However, if two objects happen to interact at a specific time and place (at a specific spacetime coordinate) then all observers will agree that the event happened at the same spacetime location. In physics this means locality is absolute.

General locality is an extension of relativity where a spacetime location is not universal. If an observer in one frame sees an interaction at a specific spacetime coordinate, another observer might not. Both observers would agree the interaction was local, but might disagree about the specific location. Thus locality is relative rather than absolute. Just as relativity was used as a way to unify space and time, general locality can be used to unify spacetime and momentum into a general “phase space.” Basically, time, location and motion are combined in this model.

While it’s a pretty wild idea, it does have some testable predictions. Since particles of different energies (momenta) see different spacetimes, their paths are slightly different. This is true for light as well, so different wavelengths of light should have slightly different speeds. This isn’t something we could measure under normal conditions, but near the event horizon of a black hole the speeds could vary enough to be measurable. Just to be clear, there’s no evidence that such a thing actually occurs at this point, and “rainbow gravity” as it is called is just one idea towards quantum gravity among a great many ideas.

The LHC could also discover magical unicorns. Credit: MoongazePonies

Where this connects to the LHC is that there has been speculation that the collider might create micro black holes. It isn’t considered likely given what we know, but some very speculative models suggest that they might occur. If these speculative models are correct, and if the LHC creates micro black holes, and if general locality and rainbow gravity is correct, and if this causes the micro black holes to decay in different ways from that expected by general relativity, then the LHC might be able to detect it. Since one of the other predictions of rainbow gravity is that the universe didn’t begin with a singularity, and since the big bang is often conflated with such a singularity in the popular press, you therefore get headlines such as “LHC may disprove big bang by discovering rainbow gravity.”

Unfortunately these types of headlines are likely to become very popular. The reality is that the LHC provides an opportunity to look for new physics beyond the standard model. There are a lot of new ideas that could be put to the test when the collider becomes active at its highest energies ever, so folks are staking their claims and placing their bets. Perhaps the journalists would do well to see who actually wins this pony race before writing about the outcome.

Paper: Giovanni Amelino-Camelia, et al. Principle of relative locality. Phys. Rev. D 84, 084010 (2011)

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There’s been much buzz about a new paper claiming that it’s observed light acting as both a particle and a wave at the same time. Is this legitimate research? Yes, absolutely. Did they actually observe particles and waves at the same time? Well…

Much of the hype around this paper is driven by some basic misconceptions regarding quantum objects. The popular view of quantum theory is that things like photons are sometimes particles and sometimes waves, and which one they become depends upon how you observe them. But in fact quantum objects are neither particles nor waves. They are quanta, which is a separate thing altogether. Under the right conditions quanta can demonstrate wave-like and particle-like behaviors, and there is complementarity between them so that quanta tend to lean toward one or the other in an experiment. But within the formalism of quantum theory, particle-wave duality is a property of the quanta as a whole. Thinking of quanta as particles or waves is far to simplistic when dealing with quantum theory. This is important to keep in mind when popular articles such as this hit the web.

As research areas such as quantum optics and quantum computing developed, we’ve gained tools to really start looking at sophisticated quantum interactions. It’s how we’ve been able to study things like the connection between the uncertainty principle and entropy, or study phase velocity in a quantum system. But since this kind of work isn’t easy to describe in simple terms, it gets hyped as “quantum mechanics gets simpler!” or “speed of light not absolute!” The same is the case here.

The team maintained a wave pattern while inducing particle-like interactions. Credit: L Piazza, et al.

So what’s really going on in this work? The team pulsed laser light at a tiny wire of conductive material (a nanowire). The light induced what is known as surface plasmon polaritons in the nanowire, which is basically an electromagnetic wave pattern within the electrons of material. Because of the size of the nanowire, the plasmon polaritons form a standing wave within the wire, which is where the “wave” aspect comes into the experiment. They also radiate light, which in a quantum sense means that photons are emanating from this standing wave. The team then aimed a beam of electrons at the set up. Some of the electrons collided with the emanating photons, and thus gained some energy. Since these collisions are particle-like, they gain specific (quantized) energy amounts from the induced photons.  Basically the team found a way to induce particle-like interactions while maintaining the overall wave aspect of the system at the same time.

Does this mean the team caused a specific photon or electron to behave as a particle and wave at the same time? No. The particle interactions with the electrons and the induced wave pattern in the wire are two separate aspects of the system. But their result is useful because it could allow us to study quantum interactions directly. This type of work is really useful for photonics and quantum computing, and it’s a clever way to interact with quantum systems.

But this is not an experiment that somehow violates quantum theory. We’ve known for a while that we should be able to do this kind of thing in theory. The achievement here is that they actually pulled it off.

Paper: L Piazza, et al. Simultaneous observation of the quantization and the interference pattern of a plasmonic near-field. Nature Communications 6:6407 DOI: 10.1038/ncomms7407 (2015)

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There’s new research being touted in the press about a possible solution to the dark energy mystery. The results, published in the peer-reviewed journal PLOS ONE argues that a radical modification of relativity can account for dark energy. The work is so abysmally awful that it makes you wonder just how such a paper got accepted for publication.

The central claim of the paper is that our understanding special relativity is wrong. Instead of all motion being relative, which causes time dilation between objects and means that there is no absolute cosmic time frame, the author argues that all motion is measured relative to some absolute time frame. This means that motion can be measured relative to this absolute frame, and things like time dilation only occurs relative to that absolute cosmic frame.

Those familiar with relativity might point out that we’ve long known that the speed of light is a universal constant in all frames of reference, and experiments such as the Michelson-Morley experiment showed that there is no absolute reference frame. Even things like GPS satellites show that relativity works, so how does one argue that there’s an absolute reference frame? As the author points out, to agree with observation, you just have to assume that the absolute frame of the universe is centered on the Earth and rotating with it.

You heard that right. The author argues that in terms of this cosmic reference frame, the Earth doesn’t move.

How to solve the dark energy mystery?

The author then goes on to argue that because of this the galaxies moving away from us are time dilated relative to our absolute frame, and since more distant galaxies are moving relative to closer galaxies, they are further time dilated. What looks like an exponential expansion of is therefore simply an effect of absolute time dilation relative to the Earth’s at-rest frame. Dark energy is therefore an illusion due to our special place in the universe.

Any physicist worth her salt would flag this work as seriously lacking. The author himself should have caught the glaring flaws in this work. But then the author is actually a cellular biologist with no publishing record in physics. Throwing all relativity out the window in order to create a “just-so” model of cosmology is what he does in his spare time. The editor of the journal should have flagged the work as well, but then his background is also biology. It’s not clear if any qualified physicist actually reviewed this work.

Then again, PLOS ONE is a different kind of journal, because it is open access.  With traditional journals, libraries and individuals pay subscriptions for access to their articles. These subscriptions aren’t cheap, so the journals live or die based upon their quality. For this reason, the journals generally decide whether to publish not only on the accuracy of the paper, but on the potential impact the work may have. More prestigious journals can charge higher subscriptions, and are therefore more selective about what they publish. PLOS ONE makes all of their work freely available to the public. To cover costs, they charge a publishing fee. In the case of PLOS ONE, that’s about $1,400 per paper.

Because income is generated per paper rather than per subscription, PLOS ONE reviews submissions only for “technical accuracy,” regardless of the quality of the work. Because of this, the quality of articles varies widely. Some are quite good, while others (like this one) not so much. Open source journals have been controversial. On the one hand they get rid of the obscenely expensive paywall that limits access to research (much of which is publicly funded), but on the other hand they can be seen as “pay to play” paper mills where anyone with enough cash can have the prestige of peer-reviewed work. While there are predatory open source journals that will publish literally anything at a cost, PLOS ONE has been seen as one of the better open source journals. But it seems in physics at least, the bar is discouragingly low.

Of course once a paper is peer reviewed, it starts getting touted in the press. The author’s home university had a press release praising the work as a new breakthrough in cosmology, which then got picked up by science news sites and posted almost verbatim, because who has the time or money to actually do science journalism. By the time it’s brought to my attention I can either ignore it and hope it doesn’t get too popular, or try to debunk yet another over-hyped science claim.

It would be easy to feel angry about this kind of thing, but mostly I’m disappointed. I’d like to see open access publishing succeed, because I honestly believe research (particularly publicly funded research) should be freely available to everyone. But when PLOS ONE publishes articles of this quality, it’s not helping advance the cause.

Paper: Edward T. Kipreos. Implications of an Absolute Simultaneity Theory for Cosmology and Universe Acceleration. DOI: 10.1371/journal.pone.0115550

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Quantum theory is one of those things that isn’t portrayed very accurately in the popular press. It’s used to justify everything from Matrix Energetics to homeopathy, it’s described as mysterious physics that no one understands, and even used to claim that the universe is a hologram. Even when claims are more mundane, the resulting press release hypes the story beyond recognition. For example, recently there’s been a flurry of news articles claiming that “Quantum physics just got simpler!” as if new research has finally solved a big mystery of physics. Not so, when you look at the actual research. The work looks at a connection between particle-wave duality, and something known as entropic uncertainty.

While quantum physics isn’t mysterious, it does have some properties we would consider strange. One of these is the fact that quantum objects have some properties similar to particles and some similar to waves. This particle-wave duality, as it is often known, shows up in the results of certain experiments, such as the photoelectric effect and the dual slit experiment. Often in popular science this is presented as objects “sometimes” being a particle and “sometimes” a wave, and it chooses which to be depending on the experiment you perform. In reality, quantum objects are simply quantum objects, and you can perform experiments that demonstrate their particle or wave behaviors.

Another aspect of quantum theory is known as Heisenberg’s uncertainty principle. This is often presented as the fact that you can’t measure both where an object is (position) and where it is going (momentum) with perfect accuracy. It’s a bit of a misrepresentation, because the uncertainty principle isn’t just a consequence of crude measuring devices, it is a fundamental aspect of quantum objects. We can’t measure an exact simultaneous momentum and position for an electron, for example, because electrons don’t have a simultaneous position and momentum. This “fuzziness” factor leads to important physical phenomena, such as quantum tunneling, which is central to solar fusion. There are other “fuzzy” quantity pairs as well, such as energy and time, which leads to thing like virtual particles and Hawking radiation.

According to the popular articles, new research has shown that particle-wave duality and the Heisenberg uncertainty principle are the same thing. But anyone who’s taken a college-level quantum mechanics course has likely seen a derivation showing that the former leads to the latter, and vice versa. So this is nothing new. What is new is how it relates to entropy. While we usually talk about quantum theory in terms of particles and waves, it can also be viewed in terms of information. In this way, Heisenberg’s uncertainty isn’t just a limit on what can be measured, its a limit on the amount of information a quantum system can contain. This is useful for a range of fields, such as quantum cryptography and quantum computing. One of the other thing we know is that the amount of information a system contains can be related to the entropy of that system. So the uncertainty principle can be generalized as a kind of entropic uncertainty.

It’s been debated whether entropic uncertainty and particle-wave duality were one and the same, just as particle-wave duality and the uncertainty principle are. An an earlier paper argued that the two weren’t equivalent, but now this new paper shows that in fact they are. This is useful for folks who study quantum information, but it isn’t a fundamental breakthrough that revolutionizes our understanding of quantum theory. It’s good work, and should be presented as such.

Unfortunately most popular articles don’t look beyond the hype.

Paper: Patrick J. Coles, et al. Equivalence of wave–particle duality to entropic uncertainty. Nature Communications, 5: 5814 (2014)

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Eta Carinae is about 7,500 light years away, and its going to explode any time now. Mind you, “any time now” means sometime over the next ten to twenty thousand years or so. But recently the star been in the news again as an existential threat to our planet. It must be that time of year again.

Just to be perfectly clear, Eta Carinae is not a danger to Earth. Even if the star exploded as a hypernova it would simply outshine the Moon for a while. It might disrupt the sleeping and hunting habits of some terrestrial critters for a while, but it won’t mean the end of life on our planet.

What’s being hyped in the press is the possibility of a gamma ray burst from Eta Carinae. If the star produced an intense GRB in our direction, then its possible we’d be in trouble. For several seconds the sky facing Eta Carinae would appear brighter than the Sun, and we’d be exposed to intense gamma rays. If that isn’t a doomsday scenario, it would at least give us a chance to live out our post apocalyptic fantasies. But stars produce GRBs along their axis of rotation, and Eta Carinae’s axis isn’t pointed at us. The star is also shrouded by a nebula, which would dampen some of the energy of a GRB.

Of all the local stars that could become supernovae, none of them are pointed in our direction, so we have no need to worry about them. But in general, they could pose a threat to extraterrestrial civilizations (should they exist). Gamma ray bursts have been proposed as an explanation for why we haven’t seen alien civilizations in the galaxy. Perhaps they’ve all been wiped out by exploding stars.

But even that is pretty speculative. So sleep easy. Even if Eta Carinae is going to blow, it doesn’t have our name on it.

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You may have heard about a “Star Trek-like” shield that scientists have found surrounding the Earth. That’s because the University of Colorado Boulder shamefully stated as much in a press release, and websites all over the world would rather copy and paste than actually do science journalism. The press release was promoting a new paper in Nature which looks at properties of the Earth’s radiation belts. 

Basically, the authors looked at satellite data on the distribution of electrons within the radiation belts. What they found was that very high-energy electrons in the belt didn’t penetrate as close to the Earth as we had thought. There is apparently some mechanism that prevents the inward drift of these electrons. Very clearly the authors state this mechanism “does not arise because of a physical boundary within the Earth’s intrinsic magnetic field.” Apparently from that Boulder’s news service concludes that it’s a Star Trek shield.

In fact, there a likely cause for this electron barrier effect. Closer to the Earth is the magnetosphere, which contains cool diffuse plasma. This region is also sometimes known as the plasmasphere. When high-energy electrons begin drifting toward the Earth, they collide with charges in the plasmasphere, which prevents them from drifting further inward, or at least eventually cooling and becoming part of the plasmasphere itself.

To confirm the details of this interaction will require more data. But it is clear that this isn’t some kind of Star Trek shield effect. Which is unfortunate, because it would be useful to use such a shield to prevent high energy hype from reaching the popular press.

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