The image above is a planetary nebula known as M2-9. It’s also known as the Butterfly nebula, but there are lots of other nebulae by that name. Planetary nebulae occur when red giant stars cast off their outer layers as they begin a transition toward becoming a white dwarf. The cast off material is caused to glow when the exposed interior of the star illuminates it with ultraviolet light, causing the material to ionize into a glowing plasma. We call them planetary nebulae because William Herschel first observed them as circular or “planetary” in shape, but we now know they come in a wide range of forms, including the layered, double-lobed shape of M2-9. Just how planetary nebulae produce such varied complexity is something we don’t fully understand. While we’re still trying to understand what the underlying mechanisms are, we do know very clearly what they aren’t.

The idea for this post came about because of a discussion with someone whose scientific interests lean toward the electric universe model. Regular readers will know I don’t find the electric universe model remotely compelling for several reasons. One of the EU ideas that has gained popularity is the idea that lobed planetary nebulae such as M2-9 are caused by plasma z-pinches in the great currents of cosmic plasma. The idea is ridiculous to anyone who’s studied astrophysics, but how do we know it’s wrong? After all, the EU folks have clearly studied this in detail, what makes me so arrogant as to tacitly dismiss the idea?

The pinch effect can crush beer cans too. Credit: Bert Hickman, Stoneridge Engineering

For those who aren’t familiar with plasma physics, a z-pinch is an effect which can occur when a plasma is constrained by a surrounding magnetic field. The magnetic force on a current is always perpendicular to the direction of the current, so when a current of plasma flows into a cylindrical magnetic field, the magnetic forces squeeze the plasma inward, causing a pinch. The pinch effect has been studied for nearly a century, and has been used in everything from crunching beer cans to work on harnessing fusion. If you look at M2-9, it’s easy to imagine a z-pinch. The plasma current flows in, pinches in the center, and flows out the other side. This is what Donald Scott and other EU folks claim, and I would agree there’s certainly a resemblance. However Scott goes further to argue that because it looks like a z-pinch, that’s what it must be. This is a classic “quacks like a duck” fallacy, which most scientists are pretty wary of. Doubly so if what it looks like would turn a hundred years of astrophysics on its head.

But this is one of those cases where there is a clear prediction from the EU model. That is, the flow of plasma is through the pinch. This means if you look at the Doppler shift of light coming from the nebula you should clearly see that the material flows in on one side and out on the other. The standard red giant model makes a very different prediction. It says the Doppler measurements should show material flowing out from the center on both sides. It turns out we’ve made Doppler observations of M2-9, and sure enough it agrees with the standard red giant model.

While this might seem like a pretty clear refutation of the z-pinch idea, but the counter argument seems to be that you could have two layers of current flow so that it goes in both directions (also contradicted by Doppler observations) or all manner of complex plasma phenomena that might explain away the Doppler data. But that isn’t very compelling because tweak theories are weak theories.

The other counter argument raised in the discussion was that astrophysicists don’t entirely understand the nebula either. If you read through the cited paper you’ll see a discussion of several models for the behavior of the lobes, peppered with phrases such as “possibly” and “might be.” It’s clear there’s a lot we don’t understand about M2-9. That’s because good scientists are cautious about making unsupported claims. We tend focus on the known unknowns.

But that’s how science pushes forward toward better models, instead of clinging to ones that clearly don’t work.

Paper: Doyle, et al. The Evolving Morphology of the Bipolar Nebula M2-9. AJ, 119:1339-1344 (2000)

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The image above features a neuron on the left, and a simulation of large scale galaxy clusters on the right. They look somewhat similar in structure, and if the internet is to be believed, this means something. And it does. Not that the universe is alive, or the cosmos is like a giant brain, but simply that sometimes two radically different things can have similarities in structure.

I’ve been getting a lot of comments and emails lately from fans of alternative science models such as the electric universe. They typically link to a video asking for my thoughts, or simply stating that it proves “us scientists” are clearly wrong. I’ve been watching a few of them, since it’s a good way to avoid grading final exams, and I’ve noticed a common trend. I’ll call it the “if it looks like a duck” argument.

A Tesla ball and the Sun have some similarities. Credit: Paul E. Anderson, et al.

For example, there’s a recent experiment by electric universe supporters known as the SAFIRE project. The basic setup is a plasma globe (or Tesla ball) where things like voltage, current, and gas pressure can be varied. What the project shows is that there are some broad similarities between a plasma ball and the Sun. There are current hot spots, an overall surface glow, and the surrounding plasma gets hotter than the surface of the ball. The similarities are kind of interesting to see, but from them many EU supporters claim that this demonstrates the Sun is actually electrically charged. That is, the similarities show that the underlying physics must be the same.

Water waves are similar to light waves.

This is a common misconception, particularly within “alternative” science. It is why you often hear arguments that one doesn’t need to get bogged down in the details (or mathematics) because the solution is so obviously clear. But physics is filled with things that are structurally similar but caused by very different underlying processes. A popular example in introductory physics is the use of water waves to demonstrate the interference of light. Water can be used to help explain the double slit experiment for light, because both water and light exhibit wave behavior. However it is completely unfounded to conclude from this that light is literally made of water.

The power of such physical analogies is that they make complex phenomena seem simple and obvious. It is why most of alternative science folks focus on videos and visual slides rather than actual research papers, and why so many people send me links to these videos as “proof” that my years of training and experience are obviously wrong.

But just as light is not made of water and galactic superclusters are not neurons, the Sun is not electric. Physical similarities are useful to explore, and they are sometimes right, but they are often wrong.

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The evidence for black holes often seems confusing to the general public. On the one hand scientists say that a black hole is an object of such great density that not even light can escape it. This leads to the question of how we can observe such a thing if it doesn’t emit light? The answer scientists give is that black holes are a source of intense energy, driving things such as quasars and galactic jets. This apparent contradiction has led some people to reject that there is any evidence for black holes at all. Supporters of the electric universe models go even further, and claim that things like quasars and jets are due to pinched electric currents or similar phenomena. But in fact a black hole being both dark and bright isn’t contradictory.

A celebrity draws a crowd. The crowd makes the noise. Credit: Mario Sorrenti

As an analogy, imagine if a famous actress such as Scarlett Johansson were to walk down a busy sidewalk. Pretty quickly a crowd would start to gather. There would be a clamor for her attention, requests for autographs and selfies. The gathering crowd would be quite loud, even if Ms. Johansson never says a word. If we were to see the shouting crowd from a distance, we could deduce that something is drawing the crowd together. If we also hear shouts of “It’s Scarlett Johansson!” “Can I get your autograph Miss Johansson?” and “We love you Scarlett!” we can deduce that the actress is the cause of all this commotion, even if we can’t see her directly. It’s possible that the crowd could be mistaken, and it is just someone who happens to look like Johansson, but if have other points of evidence such as the fact that she’s filming a movie in town and she just tweeted about leaving a restaurant a block away, we can be fairly sure it’s actually her.

A similar thing occurs with black holes. By itself a black hole doesn’t emit light, and the only way we would detect it would be by gravitational lensing or the orbital motion of nearby objects. But often black holes exist within the centers of galaxies, where there is lots of nearby gas and dust. As this material tries to move closer to the black hole, it heats up and ionizes, which can create things like a plasma accretion disk that can emit intense x-rays and gamma rays. The currents of this accretion disk can also generate strong magnetic fields, which in turn creates one of the most striking features of black holes, known as jets.

Jets are caused by streams of high energy particles that speed away from the magnetic poles of the black hole. The material is traveling so close to the speed of light that some jets give the illusion of being superluminal. So how does a black hole’s strong gravity and magnetic field cause material to stream away from it at high speed? It has to do with the fact that the magnetic poles of a black hole are where the hold on ionized gas is the weakest. Both the black hole’s gravity and its magnetic field continually try to squeeze material into the black hole, but when material reaches the polar region the  intense pressure and energy of the surrounding plasma can send stuff flying. It’s similar to the effect of squeezing a watermelon seed between your fingers. Squeeze harder and harder, and eventually the seed can pop out of your fingers and shoot away at high speed.

So while the black hole itself doesn’t emit light, the surrounding material is driven by the black hole to emit lots of light and stream jets away from its poles. Of course electric universe fans will argue that these x-ray sources and jets are proof that”everything is plasma” and that attributing these effects to a black hole is just astronomers trying to fit a square theory into round data in order to preserve their dogma. Of course what they ignore is the fact that we see similar effects with neutron stars, so we know that dense masses can drive the formation of jets and intense x-rays. We also know that a supermassive black hole exists in our own galaxy from its gravitational effect on close stars. Then there’s the fact that black holes are a prediction of general relativity, which is experimentally confirmed every day. Then again, many EU supporters don’t accept general relativity either, but that’s a whole ‘nother story.

The point is that while black holes can capture light, it doesn’t trap everything. Long before matter reaches that point of no return it is heated, ionized and squeezed so that it is quite luminous in many cases. Nothing but a supermassive black hole can drive that kind of intensity.

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In science there are models that are right. If they are right often enough or strongly enough, they become scientific theories. There are also models that are wrong. Some, such as the caloric model, seem correct for a time, and then get refuted by experiment or observation. Others are shown to be wrong from the get go. Then there are models that are “not even wrong.”

The phrase is attributed to Wolfgang Pauli, a physicist known for his intolerance of sloppy thinking. A model or idea is “not even wrong” when it’s logically inconsistent, non-falsifiable, or otherwise scientifically untenable. It’s often used as an insult. In science there’s no shame in being wrong. Lots of really good models have proven to be wrong. But if your model can’t even met the standard of being wrong, there’s plenty of shame to go around. “Not even wrong” is the realm of pseudoscience, and “it’s obvious that…” ideas with no clear connection to modern observations. It’s the type of thing you find in rambling comments on science blogs or personal websites on GeoCities. It isn’t the type of thing legitimate science blogs should be writing about.

But recently a science blog that should know better picked up a story about a new theory that could explain dark matter as an electrical effect within our galaxy. The story was then picked up by several popular science sites. It all stems from a paper that appeared recently on the arxiv. Calling it a paper is a bit of a stretch. It’s actually two pages of unsubstantiated claims with a half-page graph of the galactic rotation curve.

Measurements galactic rotation curve was one of the first hints of dark matter, but the author claims dark matter isn’t needed if the Milky Way is positively charged near its center, and negatively charged near its periphery. Assume this, and the galactic rotation curve can be explained without dark matter. Assuming that to be true for a moment, what evidence does the author give to support the idea? Simply (and I quote) “In fact it is quite implausible that the [galactic] core should remain electrically neutral.” That’s it. There are no details presented at all. Just “we can tweak the electric charge of the galaxy to fit the rotation curve.”

Of course the rotation curve of our galaxy isn’t the only evidence we have to support dark matter. We see the separation of dark matter from regular matter in objects such as the bullet cluster. We can see the effects of dark matter through gravitational lensing. Dark matter accurately predicts the clumping of galaxies on cosmic scales, among other things. Dark matter may not be the correct solution in the end, but any model trying to supplant it better be able to explain all these things and more.

This paper doesn’t do that. It doesn’t even substantiate its own claims. It is, in short, not even wrong.

Paper: S. Reucroft. Galactic Charge.  arXiv:1409.3096.

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Dark matter is one of those things in astrophysics that lots of people have trouble accepting. After all, the “experts” claim that since their gravitational models don’t agree with observation, there must be some invisible, undetectable “stuff” that isn’t regular matter. It just seems so counter-intuitive.

As I’ve noted before, the idea of dark matter isn’t invoked just to make the standard theories work. Despite our incomplete understanding of dark matter, there is significant evidence to support it. But how do we know that regular matter isn’t enough to account for the unseen mass in the universe? What if it were something like dark mode plasma?

Dark mode plasma (sometimes referred to as Birkeland currents) is an idea that mainly appears in electric universe (EU) discussions. It has some connection to traditional plasma physics, but if you Google “dark mode plasma” you mainly get references to EU sites. The basic idea is that with currents running through plasmas in the lab, you have regions where the current is strong enough to cause the plasma to emit light (glow mode), while in other regions the current is not strong enough to cause light emission (dark mode). Since the dark mode plasma doesn’t emit light, it is essentially invisible. So couldn’t it play the role of “dark matter” without some mythical exotic material.

I’ve gotten a few emails recently from EU fans making exactly that claim. As I’ve discussed before, the electric universe doesn’t really agree with observational evidence, so it would be easy to simply dismiss the idea. But I find the idea kind of interesting. After all, how do we know that we’ve accounted for all the regular matter in the Milky Way? The usual argument is that galaxies such as ours don’t just have a small amount of “missing” mass, but rather about 95% of the mass is “missing.” If 95% of the Milky Way’s mass were simply cold and dark gas and dust, it would absorb so much light that we would clearly see its effect. So what about plasma?

At at a basic level, if you had a plasma made of fully ionized hydrogen, you would simply have a sea of freely moving electrons and protons. Atoms absorb light when an electron in an atom is kicked into a higher energy orbital, and they emit light when an electron drops into a lower energy orbital. Since the electrons are not “bound” to the protons in a plasma, this can’t occur. Since light (particularly light in the visible spectrum) isn’t emitted or absorbed by the plasma it is basically invisible.  This is starting to sound a lot like dark matter!

But since the protons and electrons are electrically charged, they still interact with light.  A stream of photons passing through a plasma can still be scattered by the protons and electrons, and this is where things get interesting.  The amount of scattering you get depends upon the wavelength of the light, so if shine a brief pulse of light through a plasma, you get a dispersion of the pulse due to its interaction with the plasma. This is similar to the way glass spreads out a pulse of light by frequency. The speed of light passing through glass (or the index of refraction) is slightly different for each color, so the pulse is spread out a bit. For light and glass, the effect is small, so we don’t normally notice it, however it’s this same effect that lets prisms break light into colors.

This effect has been seen in the lab with plasmas, but it has also been observed within our galaxy. The radio signals from pulsars occur as a short pulse of light. Since there is plasma between us and a pulsar (the interstellar medium) the pulse must therefore pass through this plasma to reach us. That means we can use pulsar signals to learn about the plasma between us and the pulsar. For pulsar pulses and galactic plasma, the effect is dramatic. The radio pulse travels for light years, so there is much more time for it to spread by frequency. So instead of a simple radio pulse, we see the higher frequencies reach us a bit sooner than the lower frequencies. This spread is known as the dispersion measure (DM), and it depends on the amount plasma between the radio source and us. So the DM of radio signals lets us determine how much ionized gas there is in the galaxy.

There are lots of pulsars through our Milky Way Galaxy. By observing the DM of these pulsars we can create a map of the plasma within our galaxy, so we have a really good idea of just how much “dark plasma” there actually is. It turns out there isn’t nearly enough to account for the “missing mass” in our galaxy.

So dark mode plasma is an interesting idea, but it can’t work as a substitute for dark matter.

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There’s a cosmological model that has gained popularity on the internet known as the Electric Universe.  The basic claim of the Electric Universe model is that much of the astronomical phenomena observed in the universe is driven by electrical interactions rather than gravitational ones.  Proponents of the model claim that the Electric Universe is a much simpler solution that solves many of the cosmic mysteries mainstream astro-scientists are unable to solve.  The model is so simple that it doesn’t require any of that mathematical obfuscation found in the standard model.  But astro-scientists are too set in their ways to look at the model with an open mind.  We certainly can’t ignore such a revolutionary idea, so let’s put it to the test.

There are actually many variations to the Electric Universe model, but the most popular version seems to focus around the book by Thornhill and Talbot listed below.  It is this basic model I’ll discuss here, using the references listed at the bottom of the post.  If you want to get an overview of the model, Findlay’s ebook (available for free) is as good a reference as any.  The basic idea of this particular model is that cosmic magnetic fields interact with interstellar plasma to drive astrophysical processes.  Gravitational interactions play a negligible role in the universe.  From this idea several claims and predictions are made.  In particular:

Neither dark matter nor dark energy exist.  Black holes don’t exist. The big bang didn’t happen.

Galaxies are formed by kinks in cosmic magnetic fields.  They begin as electric quasars which then expand into modern galaxies.

Stars are electrically charged masses formed within galactic plasmas.  They are not heated by nuclear fusion within their core, but rather by a flow of plasma, similar to a florescent light.

Stars “give birth” electrically to companion stars and gas giant planets.

Redshift is not a measure of galactic distance.  It is instead a measure of galactic age.

Special Relativity is wrong.  General Relativity is wrong.

A neutrino image of the Sun. EU predicts this doesn’t exist.
Credit: R. Svoboda and K. Gordan – LSU

So, where to begin?  Let’s start with the Sun.  In the standard model, the Sun is powered by nuclear fusion in its core.  There the fusion of hydrogen into helium produces not only light and heat, but neutrinos.  In the electric universe model, the Sun is lit by electrically excited plasma.  This gives us two very clear predictions.  The first is regarding neutrinos.  The standard model predicts that the Sun will produce copious amounts of neutrinos due to nuclear interactions in its core.  The EU model predicts the Sun should produce no neutrinos.  The EU model clearly fails this test, because neutrinos are produced by the Sun.  We have not only observed solar neutrinos, we have imaged the Sun by its neutrinos.

The second prediction regarding the Sun can be seen in its spectrum.  In the standard model, the nuclear reactions in the Sun’s core produce light and heat that cause the star to shine.  If this is the case, then Sun should emit thermal radiation.  In other words, the spectrum of colors its gives off should be an almost continuous, with dark lines where cooler gasses in its upper atmosphere absorb some of the light.  If instead the Sun were lit by electrically excited plasma, as the EU model predicts, the spectrum should be a discontinuous spectrum of bright lines.  Plasma discharges do not emit a continuous spectrum of light.  Of course, what we see is a continuous spectrum as the standard model predicts.  Once again, the EU model fails.

Top: The nearly continuous spectrum of the Sun. Bottom: The bright line spectrum of a compact florescent light. Credit: John P. Beale

Unlike the neutrino observations, the solar spectrum has been well observed since the 1800s.  Long before the EU model was ever proposed.  It is a test you can do at home with a diffraction grating.  Beyond any shadow of a doubt, the Sun gives off a thermal spectrum, not a plasma one.

But lest we be accused of not giving the Electric Universe model a fair shake, let’s look at the other claims.  Are special and general relativity wrong?  Nope.  They’ve been confirmed in the lab.  In fact whenever you use your mobile phone’s GPS to find a local coffee shop, you’re communicating with satellites that correct for the effects general and special relativity.  Relativity is not merely abstract theory, it is now applied technology.

How about the idea that stars “give birth” to other stars and planets?  If that were the case, we should see stars form as isolated objects in stellar nurseries, then later form planetary systems.  Instead, what we see is protostars form with protoplanetary disks of gas and dust out of which planets form.  We’ve observed these at various stages of development around different stars, and even have dozens of examples in the Orion nebula, which is a nearby stellar nursery.

Protoplanetary disks seen in the Orion Nebula. Credit: NASA/ESA and L. Ricci (ESO)

It doesn’t look good for the Electric Universe model.  But let’s give it one last chance.  In the standard model galaxies form gravitationally, and are well developed relatively early in the universe.  Quasars are powered by black holes in the center of galaxies, and are one example of what we call active galactic nuclei.  In the EU model, quasars are formed by pinches in cosmic magnetic fields, and from them galaxies form.  Rather than being an indication of distance, redshift is a result of the age of a galaxy or quasar.  So as galaxy matures, its redshift decreases.  If the EU model is right, then we should only see quasars with high redshifts (therefore large inferred distances).  Also, the more distant (redshifted) a galaxy, the less developed it should appear.

So here’s a collection of barred spirals at different distances (or redshifts).  Notice how the most distant ones are the least developed?  No?  Actually they all look pretty similar, which is exactly what the standard model predicts, and what the EU model says absolutely shouldn’t happen.  By the way, the nearest quasar observed (3C 273) is only about 2.4 billion light years away, which means it has a smaller observed redshift than three of these fully developed galaxies.  Again in complete contradiction to the EU model.

So never let it be said that an astro-scientist has never considered the electric universe model with an open mind.  The Electric Universe model is wrong.  Provably, clearly and ridiculously wrong.

We’ve put the Electric Universe to the test.  Final Grade:  F-

Reference: The Electric Universe by Wallace Thornhill and David Talbot

Reference:  The Electric Sky by Donald E. Scott

Reference:  A Beginner’s View of Our Electric Universe by Tom Findlay (PDF)

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