Random Thoughts About Black Holes

Every now and again a thought about this or that occurs to me which I then scribble down for posterity. Here are a few that relate to the concept of the Black Hole.

* Space is not the final frontier. The ultimate challenge is to ‘boldly go’ past the event horizon of a Black Hole and see what’s to be seen. 

* One of the 64,000 $64,000 questions: Can you pour stuff down a Black Hole indefinitely, or does the Black Hole have a finite capacity and ultimately or eventually will have to spew stuff out the ‘other side’ (i.e. – thus producing a White Hole) as you keep pouring in more and more and more? I’d wager the conservation relationships and principles of physics and chemistry hold sway here. What goes in ultimately comes out. That doesn’t mean there’s not a temporary holding vessel. Or, in more human terms, you fill what’s empty; you empty what’s full, but in-between those two there’s storage in the stomach and the intestines; the lungs and the bladder.

* A Black Hole has a finite amount of mass therefore a finite amount of gravity and therefore a finite escape velocity, even if the value of same is in excess of the speed of light – the ultimate cosmic speed limit. Somehow this makes these astrophysical objects really special. However, there’s nothing different in principle vis-à-vis the Earth having a finite amount of mass, gravity and escape velocity. If Planet Earth isn’t all that special for having those three properties, why should a Black Hole be?

* If an electron acquired enough mass (say by being accelerated to near light speed), would it become a Black Hole, and if so, would the ‘inside’ still be an electron, which after all, is considered a fundamental particle? 

* Black Holes would make excellent, in fact perfect, thermos (vacuum) flasks. Pour into a Black Hole the contents of a star, say like the Sun. All that heat is then trapped and I do mean trapped!

* It’s impossible IMHO to have stuff of infinite density and occupying zero volume so whatever is inside a Black Hole has finite density and occupies a finite volume.

* What lies at the heart of a Black Hole? The traditional answer is a ‘singularity’ – a point of (near) infinite density and (close to) zero volume, matter crushed down to the final, ultimate limit – or maybe not.

Start with a hunk of matter. Keep on keeping on adding more and more and more matter (mass) to it. Your original hunk grows larger, ever denser; its gravity swells in proportion. Finally it’s just a fraction away from achieving Black Hole status – meaning its gravity is so strong not even light can escape from its grasp.

So you are a thimbleful of salt away from crossing the not-quite-yet a Black Hole to an actual Black Hole boundary. You can (barely) still see your now super-sized hunk of stuff. Now toss in that final thimbleful of stuff onto the hunk. No light now reaches you – you’ve crossed the threshold or boundary and have got a Black Hole. But do you doubt that lurking on the other side of the not-quite-yet a Black Hole to an actual Black Hole boundary, though unseen, you still have that super-sized hunk of stuff, not a singularity, but a really real solid 3-D hunk of stuff? Or, in other words, if the escape velocity of your hunk is 185,999 miles per second, no Black Hole and no singularity, but if it climbs to 186,001 miles per second you have a Black Hole and your hunk morphs into a singularity? A two mile a second difference makes that much difference? I don’t think so.

* In our Universe there are two kinds of astronomical objects. There are cosmic faucets like stars and anything else that gives off or reflects electromagnetic (EM) waves. That’s the cosmic “In Tray”. Then there are cosmic sinks and drains that absorb electromagnetic waves – Black Holes, the cosmic “Out Tray”.

It would seem to me that over the course of 13.7 billion years, an awful lot of EM (light, IR, UV, radio, microwave, gamma-ray, etc.) photons, not to mention neutrinos and cosmic rays, would have gobbled up and removed from the Universe’s inventory by being sucked into and forever residing in the insides of Black Holes. Since all astronomical observations, hence conclusions about the state of the Universe, rely on the detection of that which is emitted or reflected by cosmic faucets, then it stands to reason that in order to arrive at valid conclusions, what cosmic sinks and drains remove from the Big EM Picture must be taken into account. But is it? I’ve never read any account where the removal of EM photons from the Universe’s inventory has been considered.   

* Black Holes won’t ultimately evaporate via Hawking radiation since input of matter and energy will exceed output. In other words, more matter and energy will find there way into a Black Hole than will escape via that Hawking radiation.



A Trip Inside A Black Hole: Part One

Suicide missions are hardly unknown happenings, so presumably it wouldn’t be too hard to find a volunteer to take a long walk off a short pier and dive into the heart of a Black Hole. Well, let’s trade in the walk and the pier for a spaceship, with our suicidal pilot crewmember willing to boldly go. What might she expect? For that matter what might a chickenhearted outside observer expect to see?

Space isn’t really the final frontier; rather the inside of a Black Hole that’s inside of space really is the final frontier. Only the insanely suicidal need boldly go and explore, as it’s unlikely that the innards of a Black Hole will become a popular tourist attraction for many a millennia to come – if ever.

Okay, we have a depressed, suicidal, boldly going spaceship pilot, and she’s determined to go out in a blaze of glory and make her mark in the history books. No ordinary suicide for this woman! It’s across the event horizon threshold and down the hatch of a Black Hole. I need point out here and explain that technical term ‘event horizon’ – it’s just that location that divides the ability to return home safely from the point of no return, ever.

Countdown: Five, four, three, two, one – we have lift-off on the maiden voyage to boldly go and see what’s to be seen from the inside of a Black Hole.

As far as our suicidal pilot is concerned, everything from launch to crossing the event horizon is as normal as taking the cross-town bus to work. Time will tick by at one second per second; her mass will register normal; length ditto. However, due to Einstein’s concepts in all things being relative, an external observer will see our boldly going pilot’s reality slightly differently. 

An external observer, say relaxing back on Earth with a super powerful telescope, follows ionization trail of the boldly going voyager’s spaceship to the nearest Black Hole. Basically, what this person sees is that as the suicidal voyager blasts off from Earth, picks up speed, her ship and contents (including herself) start to shrink in length, increase in mass, and her rate-of-change (time) ticks by more slowly compared to Mr. Stay-At-Home’s own. Okay, that’s in keeping with Einstein’s relativity proclamations. 

But for some inexplicable reason, I’ve read several times some scientific author suggest that to an external observer, the suicidal pilot will not only be travelling slower and slower by the external observer’s clock as she approaches the event horizon, but in fact at contact with the event horizon her time, again as recorded by the external observer, will have stopped. In other words, the external observer will never witness the pilot’s crossover from outside the Black Hole’s event horizon to inside the Black Hole’s event horizon. The pilot will appear to be frozen in time at the event horizon, yet as far as the pilot is concerned, everything is normal in terms of time flowing at one second per second.

Now that’s a major paradox. The pilot can’t be crossing the event horizon at one second per second, while at the same time being frozen in time at the time of crossing, according to our stay-at-home observer. Of course the paradox is bullshit. To an external observer, time only comes to a screeching halt for someone external to them if they witness that someone travelling at the speed of light. Firstly, that’s a physical impossibility. There’s no reason to believe that our suicidal pilot is crossing the event horizon at light speed. There’s no absolute requirement that our suicidal pilot is crossing the event horizon at the speed of light. She in fact might have fired her retro-rockets to slow down just prior to crossing the event horizon in order to better savour the moment! So, in actual reality, our observer will see the pilot cross the event horizon, albeit at a way slower rate than the pilot herself because the pilot is travelling, hence doing the event horizon cross-over at less than the speed of light. IMHO, some ‘experts’ need to go back and redo Physics 101. 

In any event, once the external observer observes our boldly going suicidal voyager cross the event horizon, the show is over for him. Nothing that’s part and parcel of the voyager, not her ship’s reflected or emitted light, not her radio signals nor information signalling of any kind, will recross the event horizon in the outward bound direction and heading back to Earth. Our external observer can pack away his telescope and get back to more interesting pursuits, like watching daytime television. But that’s not quite the end of the story. 

And so it’s now over to the (never-to-be-revealed) recorded flight log of the voyager on her one-way trip to the Black Hole’s never-never land. Up to and including the crossover from the safe side of the event horizon to the ‘abandon hope all who enter here’ side of the event horizon, all is logged as 100% normalcy. Nothing shrinks, nothing grows in weight (increases in mass), and time does its one second per second thing as it always has done. It’s as easy as a trip from your home driveway to the supermarket parking lot, only once in the grip of the supermarket parking lot, forever in the grip of the supermarket parking lot. It’s a one-way ‘enter’ gate without a corresponding ‘exit’ sign.

Since we have no idea what the inside of a Black Hole actually is, since theoretical physics, quantum and relativity physics, break down into a mathematical mess, what our intrepid voyager will actually observe or experience is anybody’s guesstimate. There does appear to be one consensus however. Gravity rules, OK? Almost by definition there’s a hell of a lot of gravity to contend with once inside the supermarket parking lot – oops, sorry, inside the event horizon.

Now here on Earth, when standing up, gravity is pulling at your feet ever so slightly greater than it is tugging at your head – because your feet are slightly closer to Earth’s centre of mass. Earth’s gravity however is so weak that you don’t know or can’t feel the difference, but tests or experiments with extremely accurate atomic clocks show that this is true. Rate of change – time – is affected by gravity, so a clock atop a tall building runs slightly faster than an identical clock in the building’s basement. Now the gravity of a Black Hole is many, many, many orders of magnitude stronger than it is here on Terra Firma. So, it is speculated that if you are inside a Black Hole, say in free-fall, and say in a vertical position, then the gravity pulling on your feet will be not only vastly greater than if you were on Earth, but also the differential between feet and head will be orders of magnitude greater. Translated, gravity inside a Black Hole is going to stretch you out like a piece of taffy. Like in one of those fun house mirrors, you will be very, very, very tall and very, very, very thin. Ultimately you will be akin to a piece of string or spaghetti, but by that time you’ll be very, very, very dead as the human body wasn’t designed to be viable under such a state of affairs. Okay, that’s the consensus.

To be continued…

The Megaverse Concept

Everyone is aware that they live on a small blue-green planet which goes around an average star which orbits an average galaxy which is one of billions of galaxies that collectively make up our Universe. Is that all there is? Well, you may have heard of the Multiverse concept – a collection of Universes. You are probably familiar with Parallel Universes, even if just from watching or reading sci-fi. I’ll use an analogy here we’re all familiar with to illustrate these concepts – money.

Every country has money – coins and bills. Some currencies are more varied and colourful than others. Australia’s currency is one of those IMHO, but I’m probably biased living Down Under and using Australian currency. Still, the currency concept is pretty well established, so non-Australians should have no trouble following the analogy that I hope illustrates the Multiverse and the Parallel Universe, collectively a conglomerate I term a Megaverse.  

The Australian Multiverse Currency Collective

One Cent Piece: A high density copper Universe that was inhabited by the Feathertail Glider, a civilization unable to prevent the End of their Universe which has collapsed, due to high density, into a singularity and disappeared from sight.

Two Cent Piece: A high density copper Universe that was inhabited by the Frill-Necked Lizard which has also now collapsed for similar reasons into a singularity and disappeared from sight.

Five Cent Piece: A high density silver Universe inhabited by Echidnas, a race of spiny anteaters. It’s currently the smallest high density Universe.

Ten Cent Piece: A high density silver Universe inhabited by Lyrebirds.

Twenty Cent Piece: A high density silver Universe inhabited normally by the dominate race of the Platypus but with a few rarer species as well.

Fifty Cent Piece: A high density silver Universe inhabited mainly by a civilization of a very rare species indeed, the Coat of Arms (i.e. - stylized Kangaroos and Emus) but with a few rarer species as well present – they come and they go. This Universe is unique in having evolved over time from round space-time geometry to twelve-sided space-time geometry (Dodecagon). This Universe is the largest of all the high density Universes.

One Hundred Cent Piece: A high density golden Universe inhabited by a very diverse set of entities, though the dominant life form is a civilization of Kangaroos

Two Hundred Cent Piece: A high density golden Universe inhabited by a humanoid race known as the Aboriginals, an alien species if ever there was one. This Universe is the second smallest of all the known high density Universes.

All of the high density Universes is also by the way inhabited by variations of an alien parasitic species known as the Queen Lizzies.

One Dollar Bill: A low density brownish-orange Universe with a flatland space-time topology, but alas this Universe suffered the cosmological Rig Rip. RIP!

Two Dollar Bill: A low density greenish-yellow Universe with a flatland space-time topology which has now suffered a cosmological final Heat Death. A Two Dollar Bill was never all that crash hot to begin with!

Five Dollar Bill: A low density purple or violet-pinkish Universe with a flatland space-time topology. What’s interesting is that this Universe started out as a pale mauve cosmos before morphing into its current appearance. This Universe also hosts a species of the dreaded alien parasite, the Queen Lizzy. How this species made it from the high density Universes to here is a mystery of currency cosmological physics – perhaps she went through the wormhole.

Ten Dollar Bill: A low density Blue Universe with a flatland space-time topology.

Twenty Dollar Bill: A low density orange Universe with a flatland space-time topology.

Fifty Dollar Bill: A low density Yellow Universe with a flatland space-time topology.

One Hundred Dollar Bill: A low density Green Universe with a flatland space-time topology, the largest in size of all the low density Universes. What’s interesting is that this Universe started out as a light bluish-grey cosmos before morphing into its current appearance.

On some substantial note, all of the low density Universes, all those with a flatland space-time topology, are inhabited by various humanoid entities, so one might conclude that this collection or low density part of the Multiverse is older than the high density Universes. That might make sense if the younger high density Universes are expanding (due to ‘cosmic’ inflation?) and therefore density decreases over the long haul - cosmic evolution in action.

Now none of the above Universes coexist in the exact same space-time. They are all separate and unique Universes, even when in your wallet and jingling in your purse or pocket.

So that’s the collective Australian currency/coinage Multiverse comprised of various Universes, all of different colours and sizes; all with various densities and inhabitants.

But note that you can’t have just any old Universe. There’s no currency physics that allows a Three Dollar Bill Universe or a Seven Cent Coin Universe, though cosmic evolution might allow for that in the far distant future. In the meantime however, there’s allowable currency physics and unallowable currency physics when it comes the allowable and unallowable Universes.

The Australian Parallel Universe Currency Collective

A collection of just Twenty Cent Pieces or just Twenty Dollar Bill Universes would be a collection of Parallel Universes. Each Twenty Cent Piece (or Twenty Dollar Bill) Universe is the same in being a Twenty Cent Piece (or Twenty Dollar Bill) Universe. However, Parallel Universes while the same in terms of each being the same Big Picture, differ in the details – that’s what sets them apart as Parallel or Mirror Universes.

For example, in the case of the Twenty Cent Piece Universe, each Twenty Cent Piece has a case of ‘different strokes for different folks’, the ‘folks’ all being the same Big Picture (i.e. – they are just ‘folks’). Each and every Twenty Cent Piece Universe has a different fate – perhaps a differing date stamped on the coin. Some Universes will be mint and un- circulated; others eroded and/or dented and/or tarnished.

A collection of Twenty Dollar Bill Universes is also a Parallel Universe of Twenty Dollar Bill Universes. Again, each Twenty Dollar Bill Universe has a unique history apart from all other Twenty Dollar Bill Universes. Each has a differing and unique serial number; some maybe counterfeit; some are hot off the printing press, others creased, folded maybe torn. They are all Twenty Dollar Bill Universes, but all are quasi-Mirror images of the generic ideal. All exist in parallel with respect to the others - the same, but different.

Now say you have a stack of One Hundred Dollar Bill Universes. Clearly all are the same Universe, yet no two are absolutely identical – you have a Parallel Universe composed of the One Hundred Dollar Bill Universes. New Parallel One Hundred Dollar Universes are still being created as new bills are manufactured (acts of creation). Some Parallel Universes become defunct too (acts of destruction). Universes are dynamic and evolving entities. 

If you say that you are an inhabitant of the Ten Dollar Bill Universe, you’d probably have no way of contacting or exploring or even knowing about other currency Universes in other space-times. There’s probably no way you could know about and explore another Ten Dollar Bill Universe and meet yourself and discover what alternative history your other self lived; what sort of lifestyle and what sort of worldview did they have. As all Bills and Coins are isolated in their own individual space-time niches, so too are you isolated to that one bit and piece of space-time you find yourself in. The possible exception to this, as demonstrated by the Queen Lizzies, is travelling from one Universe to another via some exotic relativistic currency physics, say via currency wormholes.

In fact, since you cannot escape from your coins or bills currency Universe (currency wormholes apart), you could even think of it has being a currency Black Hole, an object from which nothing can escape! A Black Hole and a Universe might just be one and the same thing. On the other hand, a Black Hole that leaks into a White Hole could have that White Hole exit in another Universe in which case the Black Hole is the wormhole. 

Now, that’s the Megaverse in microcosm; now throw into the mix all the rest of the world’s currencies, past, present and future and you have the Big Picture of the macrocosm Megaverse. Is that all there is? Isn’t that enough?

Megaverse: A Few Notes

The Australian one and two cent coins, and the one and two dollar bill denominations are no longer manufactured and are no longer in active circulation, though technically still legal tender.

The Big Rip: The density of the [antigravity] Dark Energy in our Universe gets bigger and bigger as time goes by and the Universe evolves. Trillions of years from now the force of Dark Energy should be so strong as to rip apart even the constituent parts of molecules and atoms down to the level of their fundamental particles.

The Heat Death: We live in an expanding Universe. Unlike our ever increasing supply of Dark Energy, our heat supply is and always has been finite. Thus, over time, that finite supply is spreading out into an ever increasing volume and so the Universe is cooling, ever cooling, down. Eventually, as all the stars exhaust their fuel, the Universe will acquire an overall temperature as close to absolute zero as makes no odds. So you have, as the ultimate fate of the Universe, the slow death of heat, or the Big Chill!

The Singularity: If you gather enough mass together, the ever increasing amount of gravity will eventually become so great that mass will implode, perhaps, according to some physicists, down to a dimensionless point  of infinite density. That’s nonsense IMHO. The imploded object, the singularity, is just very, very, very tiny and very, very, very dense. It’s so dense that the intense gravity traps light and keeps even it from escaping. So you have this singularity, or in other words the heart and soul of a Black Hole.

The Wormhole: A theoretical shortcut, a gateway or passageway linking one part of the Universe to another part (or perhaps one Universe to another). Wormholes are common objects in sci-fi scenarios where you need to quickly get from Point A to Point B which is a massive distance away.

UFOs: The Stellar Rainbow Connection: Part One

It’s pretty much common knowledge that most scientists reject the reality of UFOs, at least in terms of UFOs being something ultimately anomalous, like extraterrestrial spaceships. Eyewitness testimony doesn’t cut their mustard. Photographs don’t hack it. What they demand is something nuts-and-bolts that they can study, put under a microscope, pound with a hammer, pour acid on, etc. No actual body on the lab’s slab equals no actual evidence one can study therefore there is no reality to the nonexistent body and no correspondence will be entered into on the matter. I smell a double-standard rat!

A senior SETI (Search for ExtraTerrestrial Intelligence) astronomer recently posted an essay on UFOs in the Huffington Post where he first stated:  “Allow me to first note that this is a phenomenon worthy of attention. If aliens are really hanging out in our 'hood, it's hard to imagine any other fact more worthy of study.” Then he concludes with: “The fact is, if you're certain that our planet is hosting alien visitors, the way to gain acceptance for your point of view is to prove it, not insist that the problem lies with third parties. The blame game is a cop-out.”

WTF is this guy saying? UFOs are important but it’s up to others to do all the hard yards and prove that UFOs and aliens are related. You can just about hear the writer scream out WE REQUIRE PROOF as long as the burden is on others to come up with the smoking gun!

WE REQUIRE PROOF! That’s all fine, well and good in theory, an in an ideal world, except the average member of the great unwashed doesn’t have the name-brand, academic bona-fides or resources required. No matter what ‘proof” the great unwashed offer up, the WE REQUIRE PROOF demands of the many (scientists) outweigh the abilities of the few (the great unwashed) to proved the required goods. If I ring up a top scientist at a top university and say I have a piece of an alien spaceship, do you honestly think they will listen to me or slam down the phone uttering “another bloody wacko wasting my time”! So the ‘blame game’ is perhaps more a plea for those with the scientific bona-fides, and the resources and the credibility and respected home institutions to take the great unwashed a tad more seriously when it comes to UFO experiences and get their hands dirty studying the subject.

I play the blame game. I put blame on those who could, but won’t get their hands dirty. It’s intellectual cowardice pure and simple. The fairly obvious if unstated message is I’m interested in ET, I’m a SETI scientist by profession, but I’m not interested in UFOs unless someone else provides the proof that there is an actual alien connection. I’m not interested in UFOs because I won’t get external funding to study them. That’s because I’ve got too much on my plate already. That’s because I’d rather sit on my ass and let the great unwashed do the dirty work. That’s because someone might make fun of me, like my professional colleagues. The sociology (office politics) of the science community usually runs something along the lines of don’t stray beyond the mainstream; don’t think out of the box; don’t rock the boat or you’ll end up like Jonah and tossed overboard without a whale in sight.

So holier than thou essays like that posted by ‘Mr. SETI’ aren’t really helpful; relevant scientists need to put up some legit science or shut up since if they are clearly not part of the solution, they are part of the problem standing in the way of a solution!

Let’s forget the great unwashed for the moment; let’s talk nerdy talk and deal with evidence, not proof, just evidence, that something strange is afoot via observations from astronomers,  professional colleagues of SETI scientists, and their reported anomalous observations that are in the scientific literature. Now albeit it’s ‘colleagues’ from several generations ago and way before modern SETI times, but that doesn’t alter their academic bona-fides nor what they reported in the professional literature.

I refer to the numerous historical sightings of Neith (reported satellite of Venus) and the intra-Mercurial planet Vulcan along with numerous other sightings of alleged planets inside the orbit of Mercury. Not one, or two but multi-dozens of reports are in the scientific literature for both. That’s in addition to those multi-dozens of sightings of unpredicted by uncharted and unknown objects that made unexpected transits of the Sun and Moon. So, professional astronomers are on record as having seen, for all practical purposes, unidentified ‘aerial’ phenomena. Now we know there is no Neith and there is no Vulcan, etc. so exactly what did scientists in the astronomical profession observe? A UFO by any other name is still a UFO. Okay, that’s just evidence, not proof. Still, UFO observations are not exclusively the property of the great unwashed.   

WE REQUIRE PROOF! Okay, even if scientists don’t want to actively participate, their demand WE REQUIRE PROOF (lay it on the slab in my lab) sounds reasonable, until you realise that those same scientists accept the reality of many other things that they equally can’t study on a slab in the lab, things that only can be seen or photographed.

An obvious case in point is those stars in the night sky. You see them; you can photograph them, but to date you can’t study the physical object in the laboratory! You can’t put a star on the slab. So, if stars are acceptable, why not UFOs? Well, stars can be therefore they are; UFOs can’t be therefore they aren’t*.

Scientists have a readymade excuse for not being able to verify the bona-fides of stars as laboratory specimens; they are out of reach – way too distant to grab hold of. But they still argue that stars aren’t illusions or misidentifications or all-in-the-mind or hoaxes because astrophysical theory supports stars being what scientists believe they are. Of course in a manner of speaking starlight can be ‘captured’ and analysed in the lab, and at least stars have the decency of making their appearance on schedule. Still, you cannot examine up close and personal the physical star itself.

So as a generality, in defence to an anti-UFO stance, scientists will say there are theoretical reasons for accepting the reality of things they can’t put their mitts on, implying that there are no theoretical reasons supporting the UFO ETH (ExtraTerrestrial Hypothesis). Alas and alack, as an additional counterattack, as stars (and rainbows - see below) are supported by astrophysics’ theory, there is also an actual theoretical scenario that nearly demands that there be UFOs and that UFOs be extraterrestrial spacecraft – it’s known as the Fermi Paradox. That just basically says that even if there is only one advanced technological civilization ‘out there’ with the ability to “boldly go”, then the time it would take to explore (even at low sub light velocities – say 1% to 10% the speed of light) and colonize end-to-end our galaxy is but a tiny, tiny fraction of the age of our galaxy. So where is everybody? They should, if they exist at all, by rights be here. Why would they pay special attention to the third rock from the Sun? While stars and planets are dimes-a-dozen, abodes with biospheres are probably as rare as hen’s teeth – that’s why. Planet Earth is a hen’s tooth! Alas, while astrophysical theory passes their muster, the Fermi Paradox doesn’t cut their mustard apparently.

Okay, for terrestrial scientists, physical star-stuff can’t be placed on the lab’s slab. But there are parallels much closer to home where that excuse of extreme distance falls far short. Now here’s a parallel. The rainbow is the case in point. If scientists can play UFO skeptic, I can play the role of rainbow skeptic.

To be continued…

Gamma-Ray SETI

Gamma-ray bursts are cosmic phenomena. As far as terrestrial astronomers go, they are unexpected (you can’t point your telescope in advance knowing where and when one will happen) and they are short-lived (so when one is detected you have a rather limited window of opportunity to point your telescope). Now, the question arises, are they all totally natural phenomena, or could some be manufactured, and like artificially generated radio waves, perhaps contain a message in a cosmic bottle? - A message of interest to those who seek out new life and new civilizations.

SETI (Search for ExtraTerrestrial Intelligence) scientists search for ET’s intelligent messages in the radio spectrum; and also in the visible region of the electromagnetic spectrum. Should they, despite the inherent difficulties, take the opportunity to analyse gamma-ray bursts for a signal in the gamma radiation noise? If they in fact they already have been examined for a signal I’m unaware of it or any such analysis and conclusions. It’s those unexpected and short-lived aspects that make gamma-ray SETI difficult in the extreme. It’s like sometime in the next 24 hours, on just one radio station, in some unspecified part of the world, lasting for only ten seconds, you will hear a voice. Good luck picking it up.

Gamma-ray bursts were discovered accidentally by the Vela series of satellites. The Vela satellites were sent up by the Americans to keep tabs on those naughty commies and to make sure they didn’t violate the Nuclear Test Ban Treaty. The Vela satellites indeed picked up one of the telltale signatures of atmospheric nuclear explosions (gamma-rays), except they weren’t coming from Terra Firma or within our atmosphere, but somewhere out there – way, way, way out there. Though first detected in 1967, the anomalous nitty-gritty details weren’t made public until about six years later – well these after all were top secret military spy-in-the-sky satellites.

Anyway, it was quickly realized that these cosmic gamma-ray bursts were coming from really, really far away. They weren’t sourced locally; they weren’t sourced at interplanetary distances, or even at interstellar distances. They were happening in galaxies far, far away, so far, far away that they happened a long, long time ago too (since it takes electromagnetic radiation, of which gamma-rays are a part thereof, finite times to cross finite distances). To cross such vast distances with such energy intensities suggested that gamma-ray bursts were not akin to a galaxy what a firecracker is to Planet Earth. Rather, it was more a galactic case of, well a terrestrial super-duper nuclear explosion on Planet Earth. 

Now gamma-rays are very high energy electromagnetic photons, more energetic than ultraviolet and X-rays. Even before the detection of those intergalactic gamma-ray bursts, we knew about gamma-rays since they are a natural product of electron – positron annihilation and of some radioactive decay processes.

So much for some background on gamma-rays and astronomical bursts of gamma radiation, how might that apply to SETI? Let’s assume that there is at least one highly advanced technological extraterrestrial civilization somewhere out there, who wishes to draw attention to themselves via a signal of some sort (which is not quite the same thing as actual one-on-one communication).  That desire might be akin to a more relevant terrestrial analogy like an anomous show-off graffiti artist – “here I am; I exist”. How would, or at least could, our ET do it?

Now what’s the biggest cosmic bang advertisement for your buck you can get? My understanding would be matter-antimatter annihilation. If an electron meets a positron, you get a gamma-ray. So, I wonder whether the rather anomalous and unpredictable gamma-ray bursts that are somewhat common, but not too common in the cosmos, might, or at least some of them might, be artificially created by that highly technological extraterrestrial civilization or perhaps, if plural, those extraterrestrial civilizations. An alien ‘message’ (as it were) or signal, in plain sight.

Here’s another possible scenario. Say once upon a time, billions of years ago, you had various, even numerous, high-tech extraterrestrial civilizations in various galaxies. In the classification scale of ET civilizations they would fall somewhere between a Type II (mastery of the energy output of a stellar object) and a Type III civilization (mastery over the energy resources of an entire galaxy). They shared information (‘communication’ in real time being out of the question due to the intergalactic distances involved) via radio waves, laser beams, etc. It’s efficient to send an electromagnetic packet of info in a tightly compressed, and short-lived, burst. In-person travel to and on-site visitations, possible in interplanetary and interstellar scenarios, are impossible when it comes to intergalactic scenarios. The distances are just too vast.

Now, Cosmology 101, the expanding universe, tells us that most galaxies are moving away from most other galaxies. To keep intergalactic ‘communications’ or data sharing viable over the long term, you need to shout louder as time goes by; as your neighbouring or nearby galaxies gets farther and farther away from you. Gamma-ray bursts are ‘louder’ than most other energetic phenomena in the Universe. The basic data sending principle is the same. If you can use light waves or radio waves, etc. to send a message, why not a gamma-ray?

The drawback is that this is really high-energy expenditure. But, if you are a Type II or Type III civilization, ‘burning’ this amount of energy is akin to a billionaire lighting a match.

Now the odds are very high that in all probability, gamma-ray bursts are a totally natural phenomenon, albeit still a very mysterious one. But, you never know. I think it premature to rule out ET, at least until such time as we have a better grounding in the theory behind them and/or do a detailed analysis of a typical gamma-ray burst happening looking for some signal in the cosmic noise but not finding any.