Signal out of noise

A paper this week out of the University of Washington describes research suggesting that intelligence is positively correlated with the ability to discern what someone is saying in a noisy room.

This was a little distressing to me, because I am terrible at this particular skill.  When I'm in a bar or other loud, chaotic environment, I can often pick out a few words, but understanding entire sentences is tricky.  I also run out of steam really quickly -- I can focus for a while, but suddenly the whole thing descends into a wall of noise.

The evidence, though, seems strong.  "The relationship between cognitive ability and speech-perception performance transcended diagnostic categories," said Bonnie Lau, lead author on the paper.  "That finding was consistent across all three groups studied [an autistic group, a group who had fetal alcohol syndrome, and a neurotypical control group]."

So.  Yeah.  Not a favorable result for yours truly.  I mean, I get why it makes sense; focusing on one conversation when there are others going on is a complex task.  "You have to segregate the streams of speech," Lau explained.  "You have to figure out and selectively attend to the person that you're interested in, and part of that is suppressing the competing noise characteristics.  Then you have to comprehend from a linguistic standpoint, coding each phoneme, discerning syllables and words.  There are semantic and social skills, too -- we're smiling, we're nodding.  All these factors increase the cognitive load of communicating when it is noisy."

While I'm not seriously concerned that about the implications regarding my own intelligence, it does make me wonder about sensory synthesis and interpretation in general.  A related phenomenon I've noticed is that if there is a song playing while there's noise going on -- in a restaurant, or on earphones at the gym -- I often have no idea what the song is, can't understand a single word or pick up the beat or figure out the music, until something clues me in to what the song is.  Then, all of a sudden, I find I'm able to hear it clearly.

A while back, some neuroscientists at the University of California - Berkeley elucidated what's happening in the brain that causes this oddity in auditory perception, and it provides an interesting contrast to this week's study.  A paper in Nature: Communications in 2016, by Christopher R. Holdgraf, Wendy de Heer, Brian Pasley, Jochem Rieger, Nathan Crone, Jack J. Lin, Robert T. Knight, and Frédéric E. Theunissen, considered how the perception of garbled speech changes when subjects are told what's being said -- and found through a technique called spectrotemporal receptive field mapping that the brain is able to retune itself in less than a second.

The authors write:

Experience shapes our perception of the world on a moment-to-moment basis.  This robust perceptual effect of experience parallels a change in the neural representation of stimulus features, though the nature of this representation and its plasticity are not well-understood.  Spectrotemporal receptive field (STRF) mapping describes the neural response to acoustic features, and has been used to study contextual effects on auditory receptive fields in animal models.  We performed a STRF plasticity analysis on electrophysiological data from recordings obtained directly from the human auditory cortex. Here, we report rapid, automatic plasticity of the spectrotemporal response of recorded neural ensembles, driven by previous experience with acoustic and linguistic information, and with a neurophysiological effect in the sub-second range.  This plasticity reflects increased sensitivity to spectrotemporal features, enhancing the extraction of more speech-like features from a degraded stimulus and providing the physiological basis for the observed ‘perceptual enhancement’ in understanding speech.

What astonishes me about this is how quickly the brain is able to accomplish this -- although that is certainly matched by my own experience of suddenly being able to hear lyrics of a song once I recognize what's playing.  As James Anderson put it, writing about the research in ReliaWire, "The findings... confirm hypotheses that neurons in the auditory cortex that pick out aspects of sound associated with language, the components of pitch, amplitude and timing that distinguish words or smaller sound bits called phonemes, continually tune themselves to pull meaning out of a noisy environment."

A related phenomenon is visual priming, which occurs when people are presented with a seemingly meaningless pattern of dots and blotches, such as the following:

Once you're told that the image is a cow, it's easy enough to find -- and after that, impossible to unsee.

"Something is changing in the auditory cortex to emphasize anything that might be speech-like, and increasing the gain for those features, so that I actually hear that sound in the noise," said study co-author Frédéric Theunissen.  "It’s not like I am generating those words in my head. I really have the feeling of hearing the words in the noise with this pop-out phenomenon.  It is such a mystery."

Apparently, once the set of possibilities of what you're hearing (or seeing) is narrowed, your brain is much better at extracting meaning from noise.  "Your brain tries to get around the problem of too much information by making assumptions about the world," co-author Christopher Holdgraf said.  "It says, ‘I am going to restrict the many possible things I could pull out from an auditory stimulus so that I don’t have to do a lot of processing.’  By doing that, it is faster and expends less energy."

It makes me wonder about the University of Washington finding, though, if there might be an association between poor auditory discernment and attention-related disorders like ADHD.  My own experience is that I can focus on what's being said in a noisy environment, it's just exhausting.  Perhaps -- like with the song phenomenon, and things like visual priming -- chaotic brains like mine simply can't throw away extraneous information fast enough to retune.  Eventually, it just gives up, and the whole world turns into white noise.

In any case, there's another fascinating, and mind-boggling, piece of how our brains make sense of the world.  It's wonderful that evolution could shape such an amazingly adaptive device, although the survival advantage is obvious.  The faster you are at pulling a signal out of the noise, the more likely you are to make the right decisions about what it is that you're perceiving -- whether it's you talking to a friend in a crowded bar or a proto-hominid on the African savanna trying to figure out if that odd shape in the grass is a predator lying in wait.  

Even if it means that I personally would probably have been a lion's afternoon snack.

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Double take

I ended up going down a rabbit hole yesterday -- not, honestly, a surprising nor an infrequent occurrence -- when a friend of mine asked if I'd ever heard of an English legend called the "fetch."

I had, but only because I remembered it being mentioned in (once again, unsurprisingly) an episode of Doctor Who called "Image of the Fendahl," where it was treated as kind of the same thing as a doppelgänger, a supernatural double of a living person.  And just so I can't be accused of only citing Doctor Who references, the same idea was used in the extremely creepy episode of Kolchak: The Night Stalker called "Firefall," wherein an obnoxious and arrogant orchestra conductor ends up with a duplicate who also has the nasty habit of killing people and setting stuff on fire.  The scene where the actual conductor has figured out what is happening, leading him to take refuge in a church -- and the double has climbed up the outside wall and is peering in at him through the window -- freaked me right the hell out when I was twelve years old.

Anyhow, the fetch (in English folklore) is attested at least back to the sixteenth century, but it may derive from a much older legend, the Norse fylgjur.  A fylgja is a spirit that follows someone through their life -- the name comes from an Old Norse verb meaning "to accompany" -- and can take the form either of an animal or a woman (the latter, regardless of the sex of the person; a man's fylgja is never male).  This in turn may be related to the Old English concept of a mære, a malicious, usually female, spirit that visits you at night, and is the origin of our word nightmare.

I ended up looking for similar legends in other cultures, and turns out there are a lot of them.  One example is the Finnish etiäinen, a double that can only be vaguely glimpsed on occasion, and frequently precedes a person in performing actions (s)he later does for real.  You might catch a glimpse of your significant other opening and then closing a cabinet door in the kitchen, then when you look again, there's no one there -- and you later find out that (s)he was in an entirely different part of the house at the time.  But twenty minutes later, (s)he goes into the kitchen, and opens and closes the same cabinet door.

Apparently, appearances of the etiäinen aren't considered especially ominous; there's usually no special significance to be extracted from what actions they perform.  It's just "something that happens sometimes."  Not so the tulpa, a being originally from Tibetan folklore that was eagerly adopted (and transformed) by western Spiritualists.  Originally, the tulpa was a ghostly stalker that would attach itself to a person and follow them around, generally causing trouble (the name seems to come from the Tibetan sprul pa སྤྲུལ་པ་, meaning "phantom").  But once the Spiritualists got a hold of it, it turned into something you could deliberately create.  A tulpa is a creature produced by the collective psychic energy of a group of people, that then takes on a life of its own.  Prominent Spiritualist Alexandra David-Néel said, "Once the tulpa is endowed with enough vitality to be capable of playing the part of a real being, it tends to free itself from its maker's control," and relates the experience of creating one that initially was benevolent (she describes it as "a jolly, Friar-Tuck-type monk"), but eventually it developed independent thought, so she had to kill it.

Is it just me, or is this admission kind of... unsettling?

In any case, we once again have a television reference to fall back on, this time The X Files, in the alternately hilarious and horrifying episode "Arcadia," in which Mulder and Scully have to pose as a happily married couple in order to investigate a series of murders (Mulder embraces the role enthusiastically, much to Scully's continuing annoyance), and the tulpa turns out to create itself out of garbage like coffee grounds and old banana peels.

And if you think that just plain tulpas are as weird as it gets, there are apparently people who are so addicted to My Little Pony that they have tried focused meditation and lucid dreaming techniques to bring to life characters like Pinky Pie and Rainbow Dash.  This subset of the community of "bronies" call themselves "tulpamancers" and apparently honestly believe that these characters have become real through their efforts.  I'm a big believer in the principle of "You Do You," but the whole brony subculture kind of pushes that to the limit.  Lest you think I'm making this up -- and let me say I understand why you might think that -- here's an excerpt from the Wikipedia article on "brony fandom:"

The brony fandom has developed a fandom vernacular language known as bronyspeak, which heavily references the show's content.  Examples of bronyspeak terminology include ponysona (a personalized pony character representing the creator), ponification (transformation of non-pony entities into pony form), dubtrot (a brony version of dubstep), brohoof (a brony version of brofist), and brony itself.

The next obvious place to go was to look into the fact that apparently, a lot of "bronies" want the My Little Pony characters to be real so they can have sex with them, but I drew the line there, deciding that I'd better stop while I was (sort of) ahead.

Well, ahead of where I would have been, anyhow.  I'm shuddering when I think about the searches I already did, and the insanity they're going to trigger in the targeted ads on my social media feed.  I can only imagine the horror show that would have ensued if I'd researched imaginary friend brony sex.

I don't even like thinking about that.

It's a sacrifice, but I do it all for you, Dear Readers.

So anyhow, thanks just bunches to the friend who asked me about fetches.  You just never know where discussions with me are gonna lead.  I guess that's the risk you take in talking to a person who is (1) interested in just about everything, and (2) has the attention span of a fruit fly.  

You may frequently be baffled, but you'll never be bored.

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C'mon, you wanna live forever?

This morning I was casting about for topics for Skeptophilia and happened upon one that kind of made my brain explode.  Part of this was I came across it prior to my first cup of coffee, but even now that I'm reasonably well caffeinated it still leaves me in a superposition of "Okay, I get it" and "... wait, what?"

I use the "superposition" metaphor deliberately because this, like yesterday's post about Quantum Weeping Angels, is about the weirdness of quantum physics.  To frame this, let's start with a refresher on two concepts that will be familiar to most of you -- Schrödinger's Cat and the Many-Worlds Interpretation.

Schrödinger's Cat -- a thought experiment dreamed up by the brilliant physicist Erwin Schrödinger -- looked at the bizarre prediction that with a quantum process, the phenomenon exists in the form of a wave function describing the probabilities of various outcomes.  Until observed or measured, the wave function is the reality; it's not that the outcome is already decided, and we simply don't know at the moment which option is true (as in a classical situation like flipping a coin, prior to looking to see whether heads or tails came up).  Here, the physics seemed to indicate that in a quantum process, the outcome exists in a superposition of all possible outcomes, but when it's observed, the wave function collapses into one of them, and the probabilities of the others drop to zero.

Schrödinger thought this couldn't possibly be correct, even though the mathematics was impeccable and agreed with all the experimental data (and, in fact, still stands today).  His thought experiment locked a cat in a box with a flask of poison; the flask could be broken by a remote-controlled hammer triggered by detection of a particle by a Geiger counter (particle decay and radioactivity are inherently quantum probabilistic processes).  So, is the cat dead or alive?  It was ridiculous to think it could be both (until you open the box), but that was the inevitable outcome of the quantum model.

Not only did this seem like a nonsensical prediction, a lot of physicists objected to the role of an observer.  Why should looking at something (or measuring it) affect its physical state?  And besides, what do we mean by observer?  Does it have to be conscious, or is merely interacting enough?  If a photon hits a rock, is the rock somehow "observing" it and altering its quantum mechanical state?

As a way around this, another brilliant physicist, Hugh Everett, turned the whole thing on its head by saying maybe measurement or observation doesn't collapse the wave function, it splits it -- bifurcating the universe into two branches, one in which (for example) the cat dies, and the other in which it survives.  This idea -- which gave rise to hundreds of episodes on Star Trek alone, as well as my own novel Lock & Key -- pleased some people but massively pissed off others, because it results in staggering numbers of alternate universes which then are forever walled off from each other.  The Many-Worlds Interpretation, as it has come to be called, thus appears to be intrinsically unverifiable, and another example of Wolfgang Pauli's acerbic quip, "This isn't even wrong."

Okay, so far that's just background, and probably you already knew most or all of it.  But what the article I came across this morning did was to ask a simple question:

If Many-Worlds is correct, what is it like from the point of view of Schrödinger's Cat?

Or, since people might differ on whether a cat qualifies as an observer, suppose a human is inside the box, and within any given minute, the probability of surviving is exactly one-half.  According to Many-Worlds, at every moment there is a non-zero chance of surviving and a non-zero chance of dying.  What this implies is that in one branch of the universe, you survive every time.

In other words, the Many-Worlds Interpretation seems to guarantee immortality.

Peter Byrne, who wrote a biography of Hugh Everett, danced around the issue.  "It is unlikely, however, that Everett subscribed to this [quantum immortality] view," Byrne wrote, "as the only sure thing it guarantees is that the majority of your copies will die, hardly a rational goal."  Which may well be true, but the goal isn't the issue, is it?  The reality is the issue.  Philosopher David Lewis summed it up in a lecture, in a passage that if it doesn't give you the chills, you're made of sterner stuff than I am:

As all causes of death are ultimately quantum-mechanical in nature, on the Many-Worlds Interpretation, an observer should subjectively expect with certainty to go on forever surviving whatever dangers [he or she] may encounter, as there will always be possibilities of survival, no matter how unlikely; faced with branching events of survival and death, an observer should not equally expect to experience life and death, as there is no such thing as experiencing death, and should thus divide his or her expectations only among branches where they survive.

Which brings up a rather alarming question: if some version of me survives in at least one branch of the universe, whose consciousness does that "me" represent?  The usual approach is that the "me" in some other branch is unaware of the "me" in this branch, and goes on his merry way making different decisions than I'm making; but how can there be more than just a singular "me"?  If this is true, what does "me" even mean?

And the quantum immortality argument makes this infinitely worse.  Physicist and deep thinker Max Tegmark points out that while the overall probability of your being in the "surviving branch" drops by half every minute -- and therefore, eventually becomes a really small number -- from the point of view of the "you" that has survived every branch thus far, it will still always be fifty-fifty.

Tegmark writes:

Quantum immortality posits that no one ever dies, they only appear to.  Whenever I might die, there will be another universe in which I still live, some quantum event (however remotely unlikely) which saves me from death.  Hence, it is argued, I will never actually experience my own death, but from my own perspective will live forever, even as countless others will witness me die countless times.  Life however will get very lonely, since everyone I know will eventually die (from my perspective), and it will seem I am the only one who is living forever — in fact, everyone else is living forever also, but in different universes from me.

It's not all that I'm all that fond of the idea of kicking the bucket.  I'm like my dad, who was once asked by a family friend what he wanted written on his gravestone, and he deadpanned back, "He's Not Here Yet."

But even so, can we all agree that this is a ghastly thought?

Tegmark agrees, although his objection to it -- based on the either/or nature of the thought experiment, as compared to the gradual process of many deaths -- strikes me as fairly weak.  "The fading of consciousness is a continuous process," he writes.  "Although I cannot experience a world line in which I am altogether absent, I can enter one in which my speed of thought is diminishing, my memories and other faculties fading...  I am confident that even if [a person] cannot die all at once, he can gently fade away."

All righty, but I still want to know why the physics demonstrates that this can't be true.

So that's our unsettling journey through the deep waters of quantum physics for today.  And you thought yesterday's post about "there's no such thing as local realism" was bad.  Me, I think I need to have another cup of coffee and then go play with my puppy.  He never worries about physics and philosophy.  He never worries about much of anything, far as I can tell.

What an enviable quantum state to be in.

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Quantum angels

One of the reasons I get so impatient with woo-woos is that science is plenty cool enough without making shit up.

But because quantum physics is already weird even without any embellishment or misinterpretation, it's been particularly prone to being co-opted by woo-woos in their search for explanations supporting (choose one or more of the following):

• homeopathy
• psychic abilities
• astrology
• "natural healing"
• the soul
• "chakras" and "qi"
• auras

But you don't need to do any of this to make quantum physics cool, and I've got two good examples.  Let's start with an experiment regarding quantum entanglement -- the linking of two particles in a state describable by a single wave function.  While this might seem uninteresting at first, what it implies is that altering the spin state of particle A would instantaneously change the spin state of its entangled partner, particle B -- regardless of how far apart the two were.  It's almost as if the two were engaging in faster-than-light communication.  Most physicists, of course, do not believe this is what happens -- that it's more like separating a pair of gloves, each in its own sealed box, and sending one to Alpha Centauri.  Then you open the box that's still here on Earth, and find it contains the right-handed glove; at that point, you automatically know that the one on Alpha Centauri must contain the left-handed glove.  Information didn't travel anywhere; that knowledge is just a function of how the pairing works.

However, entanglement is still one of those things that isn't fully explained, even that way.  There's a further twist on this, and that's where things get even more interesting.  Most physicists couple the entanglement phenomenon with the idea of "local realism" -- that the two particles' spin must have been pointing in some direction prior to measurement, even if we didn't know what it was.  Thus, the two entangled particles might have "agreed" (to use an admittedly anthropomorphic term) on what the spin direction would be prior to being separated, simulating communication where there was none, and preserving Einstein's idea that the theories of relativity prohibit faster-than-light communication.

Right?

Scientists at Delft University of Technology in the Netherlands seem to have closed that loophole.  Using an extremely fast random number generator, they altered the spin state of one of two entangled particles separated by 1.3 kilometers, and measured the effect on its partner.  The distance makes it impossible for sub-light-speed communication between the two.  This tosses out the idea of local realism; if the experiment's results hold -- and they certainly seem to be doing so -- the particles were indeed communicating faster than light, something that isn't supposed to be possible.  Einstein was so repelled by this idea that he called it "spooky action at a distance."

To quote the press release:

With the help of ICFO’s quantum random number generators, the Delft experiment gives a nearly perfect disproof of Einstein's world-view, in which "nothing travels faster than light" and “God does not play dice.”  At least one of these statements must be wrong.  The laws that govern the Universe may indeed be a throw of the dice.

If this wasn't weird and cool enough, a second experiment performed right here at Cornell University supported one of the weirdest results of quantum theory -- that a system cannot change while you're watching it.

Graduate students Yogesh Patil and Srivatsan K. Chakram cooled about a billion atoms of rubidium to a fraction of a degree above absolute zero, and suspended them between lasers.  Under such conditions, the atoms formed an orderly crystal lattice.  But because of an effect called "quantum tunneling," even though the atoms were cold -- and thus nearly motionless -- they could shift positions in the lattice, leading to the result that any given atom could be anywhere in the lattice at any time.

Patel and Chakram found that you can stop this effect simply by observing the atoms.

This is the best experimental verification yet of what's been nicknamed the Quantum Zeno effect, after the Greek philosopher who said that motion was impossible because anyone moving from Point A to Point B would have to cross half the distance, then half the remaining distance, then half again, and so on ad infinitum -- and thus would never arrive.  Motion, Zeno said, must therefore be an illusion.

"This is the first observation of the Quantum Zeno effect by real space measurement of atomic motion," lab director Mukund Vengalattore said.  "Also, due to the high degree of control we've been able to demonstrate in our experiments, we can gradually 'tune' the manner in which we observe these atoms.  Using this tuning, we've also been able to demonstrate an effect called 'emergent classicality' in this quantum system."

Myself, I'm not reminded so much of Zeno as I am of another thing that doesn't move while you watch it.

See what I mean?  You don't need to add all sorts of woo-woo nonsense to this stuff to make it fascinating.  It's cool enough on its own.

Of course, the problem is, understanding it takes some serious effort.  Physics is cool, but it's not easy.  All of which supports a contention I've had for years; that woo-wooism is, at its heart, based in laziness.

Me, I'd rather work a little harder and understand reality as it is.  Even if it leaves me afraid to blink.

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The rush to judgment

A loyal reader of Skeptophilia sent me an email asking me what my opinion was about two current candidates for evidence of alien spacecraft -- the Palomar transients and the object called 3I-ATLAS.

First, some facts.

The Palomar transients are some mysterious moving objects spotted on photographic plates taken at Palomar Observatory in the 1940s and 1950s, all before the launch of Sputnik 1, the first artificial satellite, in 1957.  They included both single objects and multiple objects -- in one case, five -- arrayed in a straight line.  In-depth analysis ruled out conventional explanations like meteors and flaws in the photographic plates; and curiously, there was a forty-five percent higher likelihood of transient detection within one day of nuclear testing, which was going on pretty regularly at the time.  The transients also were a little over eight percent more likely on days when there were UAP reports from other sources -- either visual observation by pilots or on-ground observers, or unexplained blips on military radar.  The authors of the paper, which appeared in Nature last week, were up front that the phenomenon was "not easily accounted for by prosaic explanations."

One of the Palomar transients, from July 1952 [Image courtesy of Stephen Bruel and Beatriz Villarroel, Nature, 20 October 2025]

3I-ATLAS is an interstellar object -- that's what the "I" stands for.  (The ATLAS part is because it was discovered by the Asteroid Terrestrial-impact Last Alert System; but fear not, the closest it will get to Earth is 1.8 astronomical units, so it poses no impact threat.)  We know it's an unbound interstellar object because of its speed and trajectory.  It's on a hyperbolic path, having come from somewhere in deep space, falling into the gravity well of the Sun, where it will ultimately slingshot its way back out of the Solar System and into deep space once again.  From analyses of the object itself, as well as the gas and dust it is currently ejecting, it appears to be an icy comet something on the order of three kilometers across, and mostly composed of frozen carbon dioxide, with small amounts of water ice, carbon monoxide, and carbonyl sulfide.

Comet 3I-ATLAS [Image licensed under the Creative Commons International Gemini Observatory/NOIRLab/NSF/AURA/Shadow the Scientist, 3I-ATLAS noirlab2525b crop, CC BY 4.0]

3I-ATLAS was immediately grabbed by (now rather notorious) astronomer Avi Loeb, whose unfortunate habit of shouting "IT'S ALIENS!" every time something unexplained happens has brought up repeated comparisons to The Boy Who Cried Wolf.  Not long after 3I-ATLAS was confirmed to be an interstellar object, Loeb and a couple of collaborators published a paper on arXiv in which they said its "anomalous characteristics" indicate it's an extraterrestrial spacecraft, and might in fact be hostile.  The claim was equally quickly shot down by a large number of exasperated astrophysicists who are sick unto death of Loeb's antics.  One, Samantha Lawler, said, "while it is important to remain open-minded about any 'testable prediction', the new paper [by Loeb et al.] pushes this sentiment to the limit...  [E]xtraordinary claims require extraordinary evidence, but unfortunately, the evidence presented is absolutely not extraordinary."

What strikes me here -- especially with regards to the (many) folks who have weighed in on the possibility that these are evidence of extraterrestrial intelligence -- is the need for a rush to judgment.  (Nota bene: this is in no way meant as a criticism of the reader who contacted me with the question; she was just interested in my take both on the facts of the case, and people's reactions to them.)  In the case of 3I-ATLAS, I think the evidence very strongly suggests that what we have here is simply a large comet of interstellar origin, so something of great interest to astronomers and astrophysicists, but unlikely otherwise to be earthshattering in any sense including the literal one.  As far as the Palomar transients go -- well, we don't know.  The most recent of them occurred seventy-odd years ago, and all we have is some old photographic plates to go by.  They're certainly curious, and I'm glad they're being looked at, but... that's about all we can say for the time being.

"Well, what about the Menzel Gap?" I've seen asked multiple times.  Isn't that suggestive?  The "Menzel Gap" refers to the fifteen-year block of missing plates attributable to actions by Harvard Observatory astronomer Donald Howard Menzel, a prominent scoffer about aliens and UFOs, who became notorious for ordering the destruction of hundreds, possibly thousands, of astronomical photographic plates stored there.  Menzel cited considerations of storage space, claiming we'd already learned as much from them as we could, but UFO aficionados hint at something darker.  Menzel had top secret security clearance, they say; he led a "clandestine life as an elite member of the U. S. intelligence community" and was systematically covering up evidence of aliens visiting the Earth in the fashion of Cigarette-Smoking Man on The X Files.

Why he and others would go to all that trouble to stop the public from finding out about aliens is never really explained.  "They were just that evil" is about the clearest it gets, often along with vague claims that it was to prevent panic amongst the populace.

As if what the government was openly doing at the time, and that made headlines worldwide, wasn't equally bad.

In any case, back to the original question: what do I think about all this?

Well, the truth is, I don't think anything.  I simply don't know.  It seems likely that whatever the Palomar transients were, they were not all due to the same cause; it could be that some were debris from nuclear testing, but that clearly doesn't account for all of them.  Menzel might have been a misguided bureaucrat, or might have been destroying the plates to prevent their being co-opted by the UFOs-and-aliens crowd, or may have had some other motives entirely.  In any case, it's okay to say "we don't know," and then just leave it there.  Perhaps researchers will find more evidence, perhaps not; in either case, the best thing is to hold the question in abeyance, indefinitely if need be.

So that's where we have to leave it.  I know that's disappointing; believe me, I've been waiting since I was a six-year-old breathlessly watching Lost in Space for unequivocal evidence of aliens.  At the moment, what we've got simply doesn't amount to much.  But if you're as intrigued by the possibilities as I am, I have two suggestions.

First, learn some actual astronomy and astrophysics.  You're less likely to fall for specious claims if you have a good command of the facts and current scientific models.

Second, keep looking up.  As has been commented many times, "It's never aliens... until it is."  I still think it's likely that life is common in the universe, and although the distances and scale (and the Einsteinian Cosmic Speed Limit) make it unlikely they've come here, it's not impossible.  Maybe there have been extraterrestrial spacecraft passing by, or even landing on, our planet.

Wouldn't it be fun if you were the first to know?  Make sure and take lots of pictures, okay?

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A voice from the static

There's a fallacy out there that is a little on the tricky side, even more so because it appears so straightforward at first.  It's called the single-cause fallacy.

Put simply (pun intended) it's the idea that complex realities can be attributed to single, often easy-to-state, causes.  The debate over slavery caused the American Civil War.  Teen violence is attributable to violent movies, TV, and video games.  High crime in American border states is caused by illegal immigration.

The problem is, the universe is a complex place, and it is rare to find just about anything that is solely due to one causative factor.  But it's a natural human tendency to gravitate toward simplistic explanations -- the KISS principle (Keep It Simple, Stupid) is something we all fall prey to.

Critical thinking, after all, is hard work.

I ran into an interesting (and less fraught, at least for most people) example of this in an article called "Electronic Voice Modulation: Voices of the Dead?", by James Alcock.  Because this article is from Scientific American, it follows Betteridge's Law -- the answer is "No" -- so the question, of course, is, "If they're not the disembodied voices of dead people, what are they?"

For those of you unfamiliar with EVPs, the gist is that you usually start with one of two things -- either an audio recording made in an empty room, or presumed "white noise" (such as the static from a radio tuned between nearby stations).  You then listen and see if you can hear words, phrases, or entire sentences.  And according to many people, these are communications from the spirits of the departed.  They're often really hard to hear, such as this one that is supposed to be a male voice whispering "Save me" (I've been through it several times, and I'm still flummoxed.)  This one is a little clearer, and includes phrases like "She'll never believe us," "She's back," and "Oliver."

[Image licensed under the Creative Commons Omegatron, White-noise, CC BY-SA 3.0]

What's difficult about this is that even setting aside two of the more obvious explanations -- (1) EVPs really are communications from the dead, and (2) they're hoaxes -- there are multiple explanations proposed for what's going on here:

1. Cross-modulation.  This happens with radio and TV static, where a device picks up snippets of a broadcast from some other medium.
2. Apophenia.  Apophenia is a brain phenomenon, where we look for (and often find) patterns in random stimuli.  Our brains are pattern-seeking devices; they often misfire and see or hear patterns that aren't there.
3. Suggestion/priming.  Note that lots of recorded examples of EVPs caption the audio track (at the relevant moment) with what the Dead Person is supposedly saying.  As James Randi said, "You can't miss it when I tell you what's there."  (This is often what's going on with allegations of backmasking, where singers are accused of including encoded, usually satanic, messages in their songs that can only be deciphered when the song is played backwards.  The message is usually indecipherable until the listener is told what it supposedly says -- at which point it jumps out.)
4. Artifacts.  These can be inadvertent alteration of the original recording because of filtering, frequency enhancement, and application of noise reduction, or even -- in old EVP claims from the days of cassette tapes -- re-recording over previous audio that didn't completely erase the original.
5. Raising the noise floor of the recording. The noise floor is the sum of all the noise produced by the electronic device itself, and thus a way to produce white noise from which EVP enthusiasts can then try to extract signals.  The problem is, this introduces another post-recording effect, because the white noise itself is usually then filtered, often using a spectral glide filter to enhance any vowel-like sounds that might occur in the recording -- something familiar to anyone who likes the music of rockers like Peter Frampton.  The processing is actually making the recording more likely to sound like speech to listeners, even if there's nothing there.
6. Wishful thinking.  It's no coincidence that positive responses to EVPs where there was no priming occur in people who already believed that EVPs are communications from the spirit world -- nor that EVP investigators almost always hear messages in their own native languages.

So EVPs -- prominently featured on all the ghost hunting programs, YouTube channels, and so on -- are not attributable to one simple cause, and that's even if you set aside for the moment the possibility that they're missives from the disembodied souls of the dead.

And that's the difficulty, isn't it?  You have some strange set of phenomena, and perhaps you explain one of them (e.g. "this particular EVP was cross-modulation, where we picked up a blip from a nearby radio station"), but you can't then jump to the conclusion that they all have that explanation.  Each instance has to be evaluated on its own merits, which is time-consuming and often frustrating.

It's why I have some sympathy for the skeptics who are inclined to dismiss them all (as well as all UFO sightings, cryptid sightings, and so on) and be done with it.  The danger, of course, is throwing out the wheat with the chaff.  You may have seen a strange story that was making the rounds -- a paper in Nature, of all places -- that was about the discovery of some odd UFOs (or UAPs -- unidentified aerial phenomena -- as I guess we're now calling them) on eighty year old photographic plates from Palomar Observatory, that showed some mysterious moving objects that "are not easily accounted for by prosaic explanations."  There was a weak correlation between their appearance and known nuclear testing, but even that seems to be a stretch.  Even the ordinarily hard-edged skeptic Sabine Hossenfelder admits that they're a mystery.  As one commenter responded, "It's never aliens... until it is."

So we're back to "critical thinking is difficult."  Blanket disbelief (i.e. cynicism) is just as lazy as gullibility is.  We have to come back time and again to the actual evidence, logic, and principles of scientific induction -- and keep your mind open, although (as Walter Kotschnig put it) "... not so open that your brains fall out."

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Surf's up

One thing that never fails to leave me feeling awestruck is when I consider that astronomers figured out the shape and size of the Milky Way Galaxy while residing inside it.

I mean, think about it.  Imagine you're a tiny being (with a telescope) sitting on a raindrop near one edge of a huge cloud, and your task is to try to measure the distances and positions of enough other raindrops to make a good guess about the size and shape of the entire cloud.  That's what the astronomers have accomplished -- enough to state with reasonable confidence that we're in one of the arms of a barred spiral galaxy.

If ever there was an image you need to study in detail, this is it.  Take a look at the original, close up.  The Solar System is in the Orion Arm, directly down from the center of the galaxy.  The thing that blew me away is the circle marked "Naked Eye Limit" -- literally every star you have ever seen without the use of a telescope is in that little circle.  [Image licensed under the Creative Commons Pablo Carlos Budassi, Milky Way map, CC BY-SA 4.0]

What's even more astonishing is that the stars making up the Milky Way (and every other galaxy) are moving.  Not fast enough, on that kind of a size scale, that the map will be inaccurate any time soon; but fast enough to be measurable from here on Earth.  In fact, it was anomalies in galactic rotation curves -- the plot of the orbital speed of stars around the center of the galaxy, as a function of their distance from the center -- that clued in the brilliant astrophysicist Vera Rubin that there was (far) more matter in galaxies than could be seen, leading to the bizarre discovery that there is five times more dark matter (matter that only interacts via gravity) than there is the ordinary matter that makes up you, me, the Earth, the Sun, and the stars.

All of this makes the new study out of the European Space Agency even more incredible.  New data from the Gaia Telescope has found that the entire Milky Way is rippling as it rotates, a little like the fluttering of a Spanish dancer's frilly skirt.  The period of this wave-like motion is on the order of ten thousand light years, and it appears to affect the entire galaxy.

The astrophysicists are still trying to figure out what's causing it.

"What makes this even more compelling is our ability, thanks to Gaia, to also measure the motions of stars within the galactic disc," said lead author Eloisa Poggio, an astronomer at the Istituto Nazionale di Astrofisica (INAF) in Italy.  "The intriguing part is not only the visual appearance of the wave structure in 3D space, but also its wave-like behavior when we analyze the motions of the stars within it."

The discovery hinged on the use of standard candles, something you may be familiar with if you've read any cosmology.  Calculating distances of astronomical objects is tricky, for the same reason that it's difficult to tell how far away a single light is at night.  If the light seems bright, is it intrinsically bright (and perhaps quite distant), or are you looking at something that is dimmer, but close to you?  The only way to calculate astronomical distances is to use the small number of objects for which we know the intrinsic brightness.  The two most common are Cepheid variables, stars for which the oscillation period of luminosity is directly related to their brightness, and type 1a supernovas, which always have about the same peak luminosity.  Between these two, astrophysicists have been able to measure the changing positions of stars as the ripple of the wave passes them.

So the stars in our galaxy are riding the cosmic surf, and at the moment no one knows why.  One possibility is that this is a leftover gravitational effect from a collision with a dwarf galaxy some time in the distant past -- a little like the ripples from dropping a pebble into a pond lasting long after the pebble has come to rest on the bottom.  But the truth is, it will take further study to figure out for sure what's causing the wave.

Me, I find the whole thing staggering.  To think that only a little over a hundred years ago, there were still astronomers arguing (vehemently) that the only galaxy in the universe was the Milky Way, and all of the other galaxies were merely small local nebulae.  The last century has placed us into a universe vaster than the ancients could ever have conceived -- and I have no doubt that the next century will astonish us further, and in ways we never could have imagined.

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