Celestial smashup

Just about everyone with even a passing interest in astronomy knows that the universe is expanding.

Ever since Edwin Hubble realized back in 1929 that almost everything outside of our own galaxy is redshifted (moving away from us), and that the degree of a galaxy's redshift is proportional to its distance from us -- something that has since been named Hubble's Law -- we've known that space is getting larger.  So, Hubble and others reasoned, if you run the clock backwards, there must have been a time when everything was collapsed together into one colossally dense point, that then for some reason that is still unknown, began to rush outward.

In other words, the Big Bang, which seems to have happened about 13.8 billion years or so ago, give or take a day or two.

However, that doesn't mean that everything is moving apart.  Within our own galaxy, there's enough mutual gravitational pull from all the massive objects therein to overcome the expansion, at least for now.  (Whether that'll continue forever remains to be seen; hold that thought, I'll get back to it.)  Even outside of our own galaxy, the members of the Local Group are gravitationally bound, and in fact, the nearest galaxy to us, Andromeda, is moving toward us at the impressive speed of 110 kilometers per second, so the Milky Way and Andromeda will eventually collide.

There are two reasons you shouldn't fret about this.  The first is that it's not going to happen for something like three billion years.  The other is that usually when two galaxies collide, shifts in the gravitational field fling stuff around, but very few collisions are expected to occur between individual stars.  Galaxies are, in fact, mostly empty space; if the Sun was the size of a typical orange and was sitting in the middle of downtown Washington D.C., the nearest star (Proxima Centauri) would be a slightly smaller orange... in San Francisco.

So while the alterations in mass distribution during a collision might throw stuff around a bit, and certainly change the shape of both galaxies, it's unlikely that any intelligent civilizations in the new combined Andromilkyway would be otherwise perturbed by it.

Note, however, I said that this is the case when two galaxies collide usually.

A paper last week in Monthly Notices of the Royal Astronomical Society describes a collision that occurred in a cluster of galaxies called "Stephan's Quintet," located (fortunately) about 290 million light years from here.  Recall my saying that the Andromeda Galaxy and Milky Way are moving toward each other at 110 kilometers per second; this enormous wreck happened eight times faster than that, with a speed that has generated a tremendous shock wave akin to a sonic boom in space.

Stephan's Quintet, showing the region affected by the collision [Image credit: Arnaudova et al., University of Hertfordshire]

"Since its discovery in 1877, Stephan's Quintet has captivated astronomers, because it represents a galactic crossroad where past collisions between galaxies have left behind a complex field of debris," said Marina Arnaudova of the University of Hertfordshire, who led the research.  "Dynamical activity in this galaxy group has now been reawakened by a galaxy smashing through it at an incredible speed of over 2 million mph (3.2 million km/h), leading to an immensely powerful shock, much like a sonic boom from a jet fighter.  As the shock moves through pockets of cold gas, it travels at hypersonic speeds – several times the speed of sound in the intergalactic medium of Stephan’s Quintet – powerful enough to rip apart electrons from atoms, leaving behind a glowing trail of charged gas, as seen with WEAVE [the William Herschel Telescope Enhanced Area Velocity Explorer]."

Which actually spells "WHTEAVE," but the discovery is cool enough that we'll let that slide.

The shock wave also compresses that interstellar gas and causes it to emit radio waves, which confirmed Arnaudova's team's discovery.

So locally, stuff can certainly move together, sometimes violently, even though the overall trend of the universe is to expand.

But.

According to a recent study by the Dark Energy Survey Project, there's a possibility that the amount of dark energy has changed over the life of the universe -- and is changing in such a way that it will affect the universe's ultimate fate.  If the amount of dark energy per unit volume of space were constant, it would mean that its effects on expansion would increase over time (since matter is thinning out, and the gravitational pull of matter is what's holding things together).  Thus, its outward pressure would proportionally increase, eventually overcoming all other attractive forces and ripping everything apart down to the constituent atoms.

This has always seemed to me to be a rather dismal prospect, not that I'll be around to see it.  Everything spread out in a thin soup of subatomic particles, and that's that.

But the new data suggests that the amount of dark energy is actually decreasing over time, meaning that its effects will gradually diminish -- and gravity will win, resulting in a "Big Crunch."  Everything turning around, falling inward, and ultimately colliding in a colossal smashup that might perhaps rebound in another Big Bang, and a new universe that resets the dials and starts it all over.

I first ran into this "oscillating universe" model when I took an astronomy class in college, and I thought it was a pretty cool idea; certainly better than the "Big Rip" that's predicted if the amount of dark energy per unit volume of space is a constant.  The point is still being debated, and (much) more data is needed to determine which is correct; but I, for one, would love it if the laws of nature were such that the universe might go through an unlimited number of bounces, and the whole game would begin again.

Maybe, just maybe, with any sentient life forms that evolve in Universe v. 2.0 getting a shot at doing it better next time.

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Deus in machina

Inevitably when I post something to the effect of "ha-ha, isn't this the weirdest thing you've ever heard?", my readers take this as some kind of challenge and respond with, "Oh, yeah?  Well, wait'll you get a load of this."

Take, for example, yesterday's post, about some "Etsy witches" who for a low-low-low payment of $7.99 will put a curse on Elon Musk (or, presumably, anyone else you want), which prompted a loyal reader of Skeptophilia to send me a link with a message saying "this should significantly raise the bar on your standards for what qualifies as bizarre."  The link turned out to be to an article in The Guardian about St. Peter's Chapel in Lucerne, Switzerland, where they've set up a confessional booth -- but instead of a priest, it's equipped with a computer and an AI interface intended to be a proxy for Jesus Christ himself.

The program is called -- I shit you not -- "Deus in Machina."

You can have a chat with Our Digital Lord and Savior in any of a hundred different languages, and get answers to whatever questions you want, from the doctrinal to the personal.  Although, says theologian Marco Schmid, who is running the whole thing, "People are advised not to disclose any personal information and confirm that they knew they were engaging with the avatar at their own risk.  It’s not a confession.  We are not intending to imitate a confession."

Which reminds me of the disclaimers on alt-med ads saying "This is not meant to address, treat, or cure any ailment, condition, or disease," when everything else in the advertisement is clearly saying that it'll address, treat, or cure an ailment, condition, or disease.

Schmid said that the church leaders had been discussing doing this for a while, and were wondering how to approach it, then settled on the "Go Big Or Go Home" model.  "It was really an experiment," Schmid said.  "We wanted to see and understand how people react to an AI...  What would they talk with him about?  Would there be interest in talking to him?  We’re probably pioneers in this...  We had a discussion about what kind of avatar it would be – a theologian, a person or a saint?  But then we realized the best figure would be Jesus himself."

[Image credit: artist Peter Diem, Lukasgesellschaft]

So far, over a thousand people have had a heart-to-heart with AI Jesus, and almost a quarter of them ranked it as a "spiritual experience."  Not all of them were impressed, however.  A local reporter covering the story tried it out, and said that the results were "trite, repetitive, and exuding a wisdom reminiscent of calendar clichés."

Given how notorious AI has become for dispensing false or downright dangerous information -- the worst example I know of being a mushroom-identification program that identified deadly Amanita mushrooms as "edible and delicious," and even provided recipes for how to cook them -- Schmid and the others involved in the AI Jesus project knew they were taking a serious chance with regards to what the digital deity might say.  "It was always a risk that the AI might dole out responses that were illegal, explicit, or offer up interpretations or spiritual advice that clashed with church teachings," Schmid said.  "We never had the impression he was saying strange things.  But of course we could never guarantee that he wouldn’t say anything strange."

This, plus the predictable backlash they've gotten from more conservative members of the Catholic Church, has convinced Schmid to pull the plug on AI Jesus for now.  "To put a Jesus like that permanently, I wouldn’t do that," Schmid said.  "Because the responsibility would be too great."

I suppose so, but to me, it opens up a whole bizarre rabbit hole of theological questions.  Do the two-hundred-some-odd people who had "spiritual experiences" really think they were talking to Jesus?  Or, more accurately, getting answers back from Jesus?  (As James Randi put it, "It's easy to talk to the dead; anyone can do it.  It's getting the dead to talk back that's the difficult part.")  I guess if you think that whatever deity you favor is all-powerful, he/she/it could presumably work through a computer to dispense some divinely-inspired wisdom upon you.  After all, every cultural practice (religious or not) has to have started somewhere, so maybe the people who object to AI Jesus are just freaking out because it's new and unfamiliar.

On the other hand, as regular readers of Skeptophilia know, I'm no great fan of AI in general, not only because of the potential for "hallucinations" (a sanitized techbro term meaning "outputting bizarre bullshit"), but because the way it's currently being developed and trained is by stealing the creativity, time, and skill of thousands of artists, musicians, and writers who never get a penny's worth of compensation.  So personally, I'm glad to wave goodbye to AI Jesus for a variety of reasons.

But given humanity's propensity for doing weird stuff, I can nearly guarantee this won't be the end of it.  Just this summer I saw a sign out in our village that a local church was doing "drive-through blessings," for your busy sinner who would like to save his immortal soul but can't be bothered to get out of his car.  Stuff like Schmid's divine interface will surely appeal to the type who wants to make religious experiences more efficient.  No need to schedule a confession with the priest; just switch on AI Jesus, and you're good to go.

I bet the next thing is that you'll be able to download an AI Jesus app, and then you don't even have to go to church.  You can whip out your phone and be granted absolution on your coffee break.

I know I'm not a religious type, but this is even giving me the heebie-jeebies.  I can't help but think that the Spiritual Experiences While-U-Wait Express Mart approach isn't going to connect you with any higher truths about the universe, and in fact isn't really benefiting anyone except the programmers who are marketing the software.

Until, like Gary Larson foresaw in The Far Side, someone thinks of equipping the Heavenly Computer with a "Smite" key.  Then we're all fucked.

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Curses! Foiled again!

Never say "How much weirder can things get?"

Ordinarily I'm the least superstitious person in the room, but I make an exception in this case.  When you say this kind of shit -- like I did when I was working out with my athletic trainer yesterday -- the universe is listening.

What spurred me to open my big mouth was, of course, all of the bizarre cabinet appointments by President-elect Donald Trump.  We had accused pedophile and sex trafficker Matt Gaetz for Attorney General; I say "had" with a smile on my face because he just withdrew, apparently sensing correctly that his accusers have the goods on him and he would be fucked sideways if he did his usual chest-thumping, I'm So Tough And Belligerent Act.  (What's amusing is that he's already resigned from Congress; I wonder if he's going to try to tell them, "Oh, wait, never mind about my resignation"?  The majority of his colleagues hate him, so my guess is they'll say "Sorry, buddy, no takesy-backsies," resulting in Gaetz doing something my grandma used to call "falling between two chairs.")  We have a WWE executive for Education Secretary and a Fox News host for Defense; both of them have also been implicated in sex scandals, which is more and more seeming like a qualification for being a Trump nominee rather than a disqualification.  We have a dangerously wacko anti-vaxxer for Health and Human Services Secretary and a loony alt-med personality to run Medicare and Medicaid.

So in an unguarded moment, I said to my trainer, "Well, at least the world can't get much weirder than it already is."

Ha.  A lot I know.

I got home from training, showered and dressed, then got a snack and sat down for a quick check of the interwebz.  And the very first thing I saw was that there is now a service on Etsy where you can pay $7.99 to have a witch put a curse on Elon Musk.

The whole thing became internet-famous because of a woman named Riley Wenckus, who apparently found out about "Etsy Witches" who will do spells for you, and she hired one of them to curse Musk -- then went on TikTok and bragged about it.  "Elon motherfucking Musk!" she shouted.  "I just paid an Etsy witch $7.99 to make your life a living hell!"

This video has been viewed five million times.

"The Three Witches from Macbeth" by Morton Cavendish (1909) [Image is in the Public Domain]

Wenckus explained her actions by saying "I was feeling really existential about what I can do," to which I respond, "Um... yay?  I think?  Or maybe 'I'm so sorry?'"  Because I have no idea what she means by "feeling existential."  But I'm happy that she's taken a concrete step toward feeling either more or less existential by cursing Musk, depending on whether she thinks it's a good or a bad thing.

I dunno.  I'm as confused as you are.

In any case, we also learn that the recipe for an anti-Musk curse involves a white candle, cayenne pepper, lavender, salt, and bay leaves.  So at least it'll make your house smell nice.

Wenckus herself says she's not sure it'll work, but is hopeful that if she's started a trend, maybe it'll accomplish something.  "I am a person grounded in reality who believes in science," she said.  "But I still think there's something to be said for having millions upon millions of people wishing for your downfall."

Now, mind you, I'm not saying that ill-wishing a horrible human being like Elon Musk isn't completely understandable.  He is one of the most genuinely loathsome people I can think of, and deserves every last one of the hexes that are thrown his way.  I'm just doubtful that it'll work.  But by all means, if you want to follow suit and add your own curse to Wenckus's (and, I'm sure, many others), knock yourself out.  You can find out how in the link provided.

As for me, I'm gonna save my $7.99, but I'm also formally announcing my abandonment of any expectations that the world will undergo some sort of normalizing regression to the mean.  Whatever the cause of how insane things have been lately -- if, for example, my suspicion is correct, and the aliens who are running the computer simulation we're all trapped in have gotten drunk and/or stoned, and now they're just fucking with us -- I give up.  Y'all win.  I'm embracing the weirdness.

I guess this is what they mean by "living in interesting times."

So go ahead, universe.  I'm ready.  Have at it.  If things are going to be terrible, at least keep making them entertaining.

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Tying God's hands

Today, for the umpteenth time, I saw the following image posted on social media:

The people who posted it apparently think that it's entirely appropriate to use the deaths of innocent people in school shootings to lob some snark at the atheists, secularists, and others who believe in the separation of church and state.  But what I want to address here is the toxicity of the mindset behind the message -- apart from what would spur someone to think that it was ever a reasonable thing to post.

First, I thought y'all were the ones who believed that God is everywhere, is omnipotent and omnipresent and omniscient and omni-what-have-you.  What you're implying here is that a handful of people who think religion has no place in a public, taxpayer-funded institution have somehow overpowered an all-powerful God's ability to do anything to stop a crazed gunman.  Probably explaining why both Oklahoma and Texas are currently poised to approve and implement new laws requiring public school teachers to work lessons from the Bible into their curricula; it's easier than doing anything to actually improve education and keep children safe, and leaves the powers-that-be with a nice smug feeling of holiness afterward. 

It's basically "Thoughts & Prayers" v. 2.0, with a side order of Showing All The Other Religions Who's Boss.

So we're already on some shaky theological grounds, but it gets worse.  What the above message suggests is that somehow, God's attitude is, "if you won't pray in schools, innocent children deserve to die."  That given the choice of using his Miraculous God Powers to stop a massacre, he just stands there smirking, and afterwards says, "See?  Told you something like this would happen if you didn't worship me all the time and everywhere.  Sorry, but my hands were tied."

Me, I think any deity that acts like this is a monster, not an all-loving beneficent creator.  That said, it's entirely consistent with the depiction of the Lord of Hosts in the Old Testament.  The Old Testament God was constantly smiting people left and right for such heinous crimes as gathering firewood on the sabbath, and when the Chosen People of Israel conquered a place, the word from above was "kill everyone, including children."

Don't believe me?  There are plenty of instances, but my favorite is 1 Samuel 15:

This is what the Lord Almighty says: "I will punish the Amalekites for what they did to Israel when they waylaid them as they came up from Egypt.  Now go, attack the Amalekites and totally destroy all that belongs to them.  Do not spare them; put to death men and women, children and infants, cattle and sheep, camels and donkeys."  So Saul summoned the men and mustered them at Telaim—two hundred thousand foot soldiers and ten thousand from Judah.

Long story short, Saul did as told, killing everyone up to and including the donkeys, but the Lord was still pissed off for some reason, and the Prophet Samuel told Saul so.  Apparently it had to do with the fact that Saul had spared the Amalekite King, Agag (like I said before, to hell with the children).  So Saul executed Agag, but the Lord still wasn't happy with him.

There's no impressing all-powerful deities, some days.

Anyhow, what this shows is that people who post bullshit like the above image are simply describing how the Old Testament God does, in fact, behave.

The whole thing brings to memory a quote from Richard Dawkins.  I know his very name justifiably raises pretty much everyone's hackles, but it's so germane to this topic that I would be remiss in not including it:

The God of the Old Testament is arguably the most unpleasant character in all fiction: jealous and proud of it; a petty, unjust, unforgiving control-freak; a vindictive, bloodthirsty ethnic cleanser; a misogynistic, homophobic, racist, infanticidal, genocidal, filicidal, pestilential, megalomaniacal, sadomasochistic, capriciously malevolent bully.

To which I can only say: touché.

The deepest problem, though, is the one that the people who post this nonsense would be the least likely to admit; when they advocate tearing down the wall between church and state, they're absolutely adamant that it can only be for the benefit of one particular church.  Start talking about having Jewish prayers or quotes from the Qu'ran or some of the Ten Thousand Sayings of Buddha festooned about the walls of classrooms, and you'll have these same people screaming bloody murder.  Hell, I bet they'd even get their knickers in a twist over which flavor of Christianity you're allowed to promote.

Hey, teachers in Oklahoma or Texas: maybe you should try posting quotes and sermons and whatnot from the Patriarch Bartholomew of the Eastern Orthodox Church, and see what happens.  Maybe even insist that the children put up Christmas decorations on January 7, when the Eastern Orthodox Church celebrates Christmas.

Could be an interesting experiment to run.

So as usual, what we're talking about is a combination of ugly theology and smug hypocrisy.  And it would be hardly worth commenting on if it weren't for the power that these attitudes still have, and the increasing degree to which they still influence policy in the United States -- something that is only going to extend further with the incoming administration, especially if more Christofascists like Pete Hegseth and Mike Huckabee get confirmed in high-level positions.

Other than railing about it here on Skeptophilia, though, I'm not sure what to do.  Anyone who really believes this -- anyone, in other words, who wasn't just trying to score some points off the nonbelievers -- has subscribed to a belief system that is very close to the definition of moral bankruptcy, so trying to reach them via argument is probably a forlorn hope.

And people talk about us atheists being amoral.

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The sound of the whistle

In his absolutely terrifying 1904 short story "Oh, Whistle and I'll Come For You, My Lad," British writer M. R. James tells us about a young professor named Parkins who is recovering from an emotional upset and decides to take a seaside R&R in coastal Suffolk.

Parkins is wandering the beach one day, and finds, half-buried in the sand, an ancient bronze whistle.  A historian himself, he is intrigued, and cleans it up, discovering upon inspection that it has two inscriptions, both in Latin: "Quis Est Iste Qui Venit?" ("Who is this who is coming?") and the more mysterious "Fur Fla/Fle Bis," which Parkins is unable to disentangle, but which James intended us to piece together as "Fūr: flābis, flēbis," which roughly translates to "Thief: if you shall blow, you shall weep."

Parkins, as it turns out, should have worked harder to figure out the second inscription.

Evidently not realizing that he is in a horror story, he blows the whistle, which is unexpectedly loud and shrill.  Nothing happens -- at least immediately.  But later that day, while out on the beach, he sees in the distance an "indistinct personage" who seems to be attempting to catch up with him, but never does.  The person moves in a strange way -- a kind of flapping, flailing motion, not at all like a human running.

Then he starts hearing noises at night, which at first he attributes to mice.  A bellhop has a panic attack while looking up at Parkins's room from the outside, saying that there was a "horrible face" in the window.  One of the maids complains that Parkins didn't have to pull all the bedclothes off the bed and throw them onto the floor in the morning -- when he'd done no such thing.

What the whistle had summoned was an incorporeal creature who fashions itself a body out of whatever happens to be handy -- in the case of the bellhop, for example, a twist of fabric from the curtains.  At the end of the story, as Parkins is lying in bed, sleepless, the light of the Moon coming in through the window, he sees the sheets and blankets on the other bed suddenly pull together into a crumpled humanoid form, and sit up -- then it reaches out its cloth arms, feeling around to try and find him.

It is one of the most flat-out terrifying scenes I've ever read.

I was put in mind of James's story (rather reluctantly) by a paper in the journal Nature Communications Psychology about a fascinating study of what are called "Aztec death whistles" -- ceramic whistles shaped like skulls, that when blown generate an unearthly sound that resembles a high-pitched human scream.

The study looked at human responses to the sounds, and found that one hundred percent of volunteers had "strongly aversive reactions," which is science-speak for "the test subjects nearly pissed their pants."  The researchers did fMRI scans of volunteers' brains, which showed strong responses in the auditory cortex and amygdala (the latter being central to the fear response).  The authors write:

All four skull whistle sound categories were rated similarly in terms of their high negative valence, and they revealed significantly the most negative valence compared with all other sound categories.  Skull whistles trigger significantly higher urgent tendencies than all other sound categories...  Skull whistles sounded more unnatural than original biological sounds (human, animal, nature) and exterior sounds, and they largely also sounded less natural than some musical sounds (music, instrument)...  The sound of skull whistles thus seems to carry a negative emotional meaning of relevant arousal intensity.  This seems to trigger urgent response tendencies in listeners, which is a typical psychoacoustic and affective profile of aversive, scary, and startling sounds.

The authors admit they have no idea what the whistles were used for, but suggest that they might have been played during human sacrifices.

Because those apparently weren't horrifying enough already.

Anyhow, naturally I wanted to hear these things for myself, so I clicked on the link that has clips of the whistles being blown.

I'd read the paper, so I should have been ready for it, but holy shit, those things are scary-sounding.  The hairs on the back of my neck stood up.  I'm really sound-sensitive, so maybe I had a stronger reaction than you will; but it bears mention that when I listened to the clips, my dog Rosie was asleep on the papasan chair in my office, and she freaked.  Normally Rosie is the most placid of animals; she's very used to my having music going on my computer, as well as hearing voices and other sounds from things like YouTube videos, and ordinarily has zero reaction to any of it.  But when this thing sounded -- and I didn't even have the volume up very high -- she jolted awake, eyes wide, hackles raised, and looked terrified.

So whatever it is that these Aztec death whistles are doing to the brain, I can say with some confidence that dogs also have the same response (at least to judge by a sample size of one).

However, I'm happy to report that thus far, playing the whistle noises hasn't generated any other untoward effects.  I haven't seen any horrible faces in my office window, and I've yet to be chased around my house by an animated bedsheet.  So that's good.  But I don't think I'm going to listen to those whistle clips again.

Suffice it to say that, like M. R. James's character Parkins, I'm not eager to repeat the experience.

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Paradoxes and pointlessness

In his 1967 short story "Thus We Frustrate Charlemagne," writer R. A. Lafferty took one of the first looks at something that since has become a standard trope in science fiction; going back into the past and doing something that changes history.

In his hilarious take on things, some time-machine-wielding scientists pick an event in history that seems to have been a critical juncture (they chose the near-miss assassination attempt on Charlemagne in 778 C.E. that immediately preceded the Battle of Roncevaux), then send an "avatar" back in time to change what happened.  The avatar kills the guy who saved Charlemagne's life, Charlemagne himself is killed, and his consolidation of power into what would become the Holy Roman Empire never happens.

Big deal, right?  Major repercussions down throughout European history?  Well, what happens is that when the change occurs, it also changes the memories of the scientists -- how they were educated, what they knew of history.  The avatar comes back, and everything is different, but the scientists are completely unaware of what's happened -- because their history now includes the change the avatar made.

So they decide that Charlemagne's assassination must have had no effect on anything, and they pick a different historical event to change.  The avatar goes back to try again -- with the same results.

Each time the avatar returns, things have become more and more different from where they started -- and still, none of the characters inside the story can tell.  They can never, in C. S. Lewis's words, "know what might have happened;" no matter what they do, those alternate timelines remain forever outside their ability to see.

In the end, the scientists give up.  Nothing, they conclude, has any effect on the course of events, so trying to change history is a complete waste of time.

One has to wonder if Harvard astrophysicist Avi Loeb has read Lafferty's story, because Loeb just authored an article in The Debrief entitled, "The Wormhole Dilemma: Could Advanced Civilizations Use Time Travel to Rewrite History?"  Which, incidentally, is a fine example of Betteridge's Law -- "any headline phrased as a question can be answered with the word 'no.'"

Before we get into what the article says, I have to say that I'm getting a little fed up with Loeb himself.  He's something of a frequent flier on Skeptophilia and other science-based skepticism websites (such as the one run by the excellent Jason Colavito), most recently for his strident claim that meteoric debris found in the Pacific Ocean was from the wreckage of an alien spacecraft.  (tl;dr: It wasn't.)  

I know we skeptical types can be a little hard to budge sometimes, and a criticism levied against us with at least some measure of fairness is that we're so steeped in doubting that we wouldn't believe evidence if we had it.  But even so, Loeb swings so far in the opposite direction that it's become difficult to take anything he says seriously.  In the article in The Debrief, he talks about how wormholes have been shown to be mathematically consistent with what we know about physics (correct), and that Kip Thorne and Stephen Hawking demonstrated that they could theoretically be kept open long enough to allow passage of something from one point in spacetime to another (also correct).  

This would require, however, the use of something with negative mass-energy to stabilize the wormhole so it doesn't snap shut immediately.  Which is a bit of a sticking point, because there's never been any proof that such a something actually exists.

Oh, but that's no problem, Loeb says; dark energy has negative (repulsive) energy, so an advanced civilization could "excavate dark energy from the cosmic reservoir and mold it into a wormhole."  He admits that we don't know if this is possible because we still have no idea what dark energy actually is, but then goes into a long bit about how we (or well-intentioned aliens) could use such a wormhole to "fix history," starting with getting rid of Adolf Hitler and preventing the Holocaust.

A laudable goal, no doubt, but let's just hang on a moment.

[Image is in the Public Domain courtesy of artist Martin Johnson]

The idea of the altering of history potentially creating intractable paradoxes is a staple of science fiction, ever since Lafferty (and Ray Bradbury in his brilliant and devastating short story "The Sound of Thunder") brought it into the public awareness.  Besides my own novel Lock & Key, in which such a paradox wipes out all of humanity except for one dubiously lucky man who somehow escapes being erased and ends up having to fix the problem, this sort of thing seemed to happen every other week on Star Trek: The Next Generation, where one comes away with the sense that the space-time continuum is as flimsy as a wet Kleenex.  It may be that there is some sort of built-in protection in the universe for preventing paradoxes -- such as the famous example of going back in time and killing your own grandfather -- but even that point is pure speculation, because the physicists haven't shown that time travel into the past is possible, much less practical.

So Loeb's article is, honestly, a little pointless.  He looks at an idea that countless fiction writers -- including myself -- have been exploring ad nauseam since at least 1967, and adds nothing to the conversation from a scientific perspective other than saying, "Hey, maybe superpowerful aliens could do it!"  As such, what he's done is really nothing more than mental masturbation.

I know I'm coming away sounding like a killjoy, here.  It's not that this stuff isn't fun to think about; I get that part of it.  But yet another article from Loeb talking about how (1) highly-advanced alien civilizations we know nothing about about might (2) use technology that requires an unknown form of exotic matter we also know nothing about to (3) accomplish something physicists aren't even sure is possible, isn't doing anything but giving new meaning to the phrase "Okay, that's a bit far-fetched."

The whole thing put me in mind of physicist Sabine Hossenfelder's recent, rather dismal, video "Science is in Trouble, and It Worries Me."  Her contention is that science's contribution to progress in our understanding of the universe, and to improving the wellbeing of humanity, has slowed way down -- that (in her words) "most of what gets published is bullshit."  Not that what gets published is false; that's not what she means.  Just that it's pointless.  The emphasis on science being on the cutting edge, on pushing the limits of what we know, on being "disruptive" (in a good sense), has all but vanished.  Instead, the money-making model -- writing papers so you get citations so you get grants so you can write more papers, and so on and so on -- has blunted the edge of what academia accomplishes, or even can accomplish.

And I can't help but throw this fluff piece by Loeb into that same mix.  As a struggling writer who has yet to exceed a three-figure income from my writing in a given year, I have to wonder how much The Debrief paid Loeb for his article.  I shouldn't be envious of another writer, I guess; and honestly, I wouldn't be if what Loeb had written had scientific merit, or even substance.

But as is, the whole thing pisses me off.  It adds to the public perception of scientists as speculative hand-wavers, gives the credulous the impression that something is possible when it probably isn't, teaches the reader nothing most of us haven't already known for years, and puts another entirely undeserved feather in Avi Loeb's cap.

My general sense is that he was doing less harm when he was looking for an alien hiding behind every tree.

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Very like a mammal

"Prior to the End-Cretaceous Extinction, mammals were all small and shrew-like, restricted to skulking, scurrying forms because of competition from, and predation by, dinosaurs.  Once the dinosaurs were out of the way, the mammals were free to diversify and to grow larger."

How many times have we all heard this?  And it certainly sounds plausible; being large and obvious when there were hungry carnivores like Velociraptor around seems like a good way to be turned into dinner.

But the fossil record shows that the truth is more complicated -- and far more interesting.

Take, for example, Castorocauda lutrasimilis.  This animal was around fifty centimeters long and weighed in at around three-quarters of a kilogram.  It was sleek, streamlined, with a bullet-shaped head, a fine pelt of soft fur, and a flat, paddle-like tail.  Here's an artist's reconstruction:

[Image licensed under the Creative Commons Nobu Tamura (http://spinops.blogspot.com), Castorocauda BW, CC BY 3.0]

If you're reminded of something like a beaver or an otter, you're not alone; the scientific name means "beaver's tail and looks like an otter."  Surprisingly, it was closely related to neither one; in fact, it's not even a true mammal, but a docodont, which split off from other mammal-like forms (including our own ancestors) way back in the early Jurassic period -- while there were plenty of dinosaurs lumbering around the place.

The docodonts, and a handful of other groups of Mesozoic cousins to mammals, are mostly known from the exceptional fossil beds of the Tiaojishan Formation in northern China, where paleontologists have found a wealth of mid- to late-Jurassic fossils of mammaliaformes -- as they call Mesozoic mammals and their near relatives.  And amongst those fossils they not only find otter-like aquatic species, but ones that have adaptations an awful lot like moles, squirrels, and possums.

This adds another cluster to the list of cool examples of convergent evolution, where two only distantly-related species evolve to resemble each other superficially because of similar selective pressures.  (A famous modern pair is the North American flying squirrel and the Australian sugar glider; at a quick glance these two look very much alike, but a closer examination would show that they're not even in the same order.  The flying squirrel is a rodent, and the sugar glider a marsupial.)

The docodonts and other side branches of the mammaliaformes all disappeared by the middle of the Cretaceous Period, replaced by true mammals including multituberculates, monotremes, marsupials, and placentals.  Why this happened isn't certain; given that we know the non-mammal mammaliaformes from only a few isolated geological strata, our information on them is limited.  We do know, however, that the mammals who survived were mostly "small and shrew-like," so there's a grain of truth to the old model.

What's most fascinating is that after the End-Cretaceous Extinction, these survivors re-diversified, and "re-invented" a bunch of the adaptations the docodonts had a hundred million years earlier.  This has interesting implications, not only for the evolution of life on Earth but for the kinds of living things we might expect to find on other planets.  It's long been a fascinating question to me to what extent evolution is constrained -- what limitations there are on natural selection that might result in its generating the same patterns over and over because those are the features that work best in pretty much any environment.  There are a few that seem likely, such as having the main sensory organs near the mouth and at the anterior of the body; I'd expect those to be frequent no matter where you go.

But what Castorocauda and the other docodonts show is that other sorts of traits can repeat, too.  After all, there are only so many ways you can move around, find food, find shelter, avoid being eaten, and regulate your own body temperature.  It might be surprising at first that the otter-like Castorocauda (and the possum-like Borealestes and the squirrel-like Shenshou) "re-evolved" (as it were) over a hundred million years later, but it suggests that making a living requires the same toolkit pretty much regardless.  

So maybe when we find life on another planet, it'll be far more familiar than we expect -- and that "life as we know it, Jim" might be there to greet us when we arrive.

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