One of the great mysteries of particle physics was a very strange and still unexplained
event that happened in 1991. The detection happened at the Fly’s Eye telescope in Utah
which was a detector that searched the upper atmosphere for indicators of a
shower of particles that occurs whenever a high energy cosmic ray hits the upper atmosphere,
something it did very well and helped to use the atmosphere itself in the study of high energy
physics. But one detection stood out, and was nothing short of stunning, this particle which
may have been a proton but that’s not certain was unbelievably high energy for a single particle,
about 40 million times more energetic than anything we’ve produced in a particle accelerator.
In fact, the particle was so high energy that it was traveling at high relativistic speeds,
experiencing very severe time dilation. Now remember, a proton is actual matter with mass,
so to see something like that traveling at almost the speed of light, way above 99 percent of it,
is incredible and vexing at the same time. To give a sense of the time dilation involved, from our
frame of reference if the particle had traveled 1.5 billion light years, we would see it having
taken almost that amount of time at near the speed of light to cross the distance. But from the
particle’s perspective, time was dilated so much that the same journey in its frame of reference
would have taken only 1.7 days. 1.7 Days to go 1.5 billion light-years from its perspective.
Now remember, this was a subatomic particle, which are obviously unbelievably small,
yet it hit earth's atmosphere with an energy comparable to a baseball being thrown at high
speed hitting someone’s glove. That was one single particle packing that much energy.
Subsequently, more particles of this energy hitting the atmosphere have been observed,
and while they are quite rare, they are occasionally detected. So here’s the problem,
no known phenomenon in nature seems capable of slinging particles out at these energies.
There are some candidates however. One hypothesis is that young neutron stars
spinning rapidly may have a mechanism for accelerating iron nuclei to these speeds,
or even a phenomenon related to when a neutron star converts itself into strange matter.
There is some evidence for this, in that supernova remnants have been observed to produce
ultra high energy gamma rays, but not atomic nuclei. Other options include active galactic
cores, energetic supernovas, whatever causes gamma ray bursts and so on. Even
dark matter has been invoked in that it’s thought that very active galactic nuclei
may be able to actually convert particles of Dark Matter into high energy protons, but as with
anything related to dark matter, that’s subject to change since we know almost nothing about it.
But there’s a problem with every one of those options.
One set of observations from 2014 suggests that the source for these particles is localized to an
area in the constellation Ursa Major. With all the proposed potential sources, none of them fit that,
and that the particles should be coming from all directions but apparently
they are not. It also seems that whatever the source is, it’s somewhat close to our galaxy,
limiting the explanations offered by active galactic nuclei. In short, the source of these
highly energetic particles that we occasionally observe remain unexplained over 20 years after
their discovery. And in the process the mystery of the source has only deepened.
That has led to some suggestions that they might actually represent an alien technosignature.
One of the problems with looking for technosignatures is that we only have
ideas on what they might look like, but no actual observations of them, so we’re left
in the position of trying to envision what alien technology might be like, and what forms
they might use. Obviously that’s fraught with problems, since it’s entirely guesswork without an
actual observation of an alien civilization. But assuming that highly advanced alien civilizations
are out there and are trying to scientifically probe the universe as we do, then there is a
way for a particle to be accelerated to the speeds shown by ultra high energy cosmic rays.
It’s an extremely powerful particle accelerator far beyond what we have,
and in this case, it would need to be astonishingly enormous. Such an accelerator
would consume epic amounts of energy, and indeed could be the size of a solar system or larger.
The benefit however would be that certain things that are experimentally out of reach right now,
such as testing string theory, become within reach with such an accelerator.
In fact, building such a thing may offer the only chance a civilization has
at a complete understanding of the universe and the big bang. As a result, building giant
accelerators could be on the bucket list for all civilizations of advanced enough technology.
Perhaps it might even be priority number 1. And that means that there would be such accelerators
tossing out high energy particles into space built by highly capable, probably ancient civilizations.
A variant of this idea would be high energy particle communications.
If the alien civilization concludes that the best method of communication isn’t radio,
or Arnold louvers in the visual spectrum, or anything like that, it might rather choose
to use high energy particles arranged in an unnatural pattern to make contact. After all,
it’s not particularly difficult to detect these events if you have the instrumentation to do so,
and methods of communication like this have been practiced by humans, most famously Morse code.
Unfortunately, you’d need a key to figure out what they were actually saying, but otherwise
it’s not hard to pulse numbers out, such as prime numbers, in a way that nature couldn’t do.
So far, no evidence of a pattern has been seen, but the sampling of events like this is still very
small. And there is also the problem of cadence, aliens may not work on the same time scales we do,
and we might only see a particle every five years, or longer, so the only way to discern
any patterns could be very long-term constant observation. It might even take centuries before
a pattern becomes evident. One might say that any regular pulse might get the message across,
but that’s an issue in itself, nature can produce regular pulses, such as pulsars,
so in that event you probably could never tell the difference between particles regularly being
artificially produced, or those produced by some repeating phenomenon like a rotating neutron star.
Any message would have to be more detailed than that.
So this one remains a possibility, but we have seen no indicators yet that aliens produce
these strangely high energy particles. It merely remains a question as to how nature can do it.
But there are other possibilities beyond a megastructure particle accelerator.
Another variant of this concept is that some other high energy activity by aliens might produce
particles at these energies. An example here would be an alcubierre type warp drive coming out of
warp, which has been advanced as a possible origin for fast radio bursts, though those are starting
to look astrophysical in nature rather than alien. The alcubierre drive in a nutshell is a warp drive
concept in keeping with general relativity that allows you to isolate a piece of space time and
move it across the universe with your star ship sitting stationary in the center. You aren’t
moving, but space time itself is, and space time is not beholden to the speed of light limitation.
But it’s become clear that even though huge amounts of energy are needed to accomplish this,
it would also create some very strange radiation, and that radiation could include
high energy protons that get accelerated and then might be released when someone comes out of warp.
This would be an unbelievably dangerous position to be in if you were on a planet where someone
just came out of warp near, such a thing could irradiate entire worlds in the wrong position.
But it is at least a speculative artificial source for these high energy particles.
But this particle detection, known as the oh my god particle,
isn’t the only incidence of such high energy particles, there have been seven detection since,
but these particles aren’t the only type of high energy particle in the universe.
And one type may even pose a health risk. These are known as HZE ions. These are
basically stripped atomic nuclei that can be any element above helium on the periodic table,
and like any cosmic ray, they travel at near the speed of light.
There is a strong candidate here for what accelerates HZE ions to high energies
and its supernovas. Supernovas are unbelievably violent explosive events
that could easily accelerate individual particles to relativistic speeds,
especially regarding the titanic shock waves that move through the materials involved
in the exploding star. There are literally supernova bullets hitting the earth’s atmosphere.
But small amounts of HZE ions at lower energies can be produced by the sun, particularly during
solar flares. However, HZE ions as a form of cosmic ray pose a threat to astronauts.
The worst galactic cosmic rays are from heavy, highly ionized nuclei of
iron. These are even worse than the protons accelerated during solar flares that make up
a significant threat to biology. You can shield against those however.
But the iron nuclei being heavy are far more energetic to the point that they penetrate
most shielding feasible for a spacecraft and then enter the body and shred the DNA and then
causing cell death. But the exposure is low. For HZE ions in general during solar particle events
they are only a small part of the dose an astronaut receives which is mainly protons.
And they are only a small part of the cosmic ray equation. But the point is, space is dangerous
in ways that we may not fully understand yet. Thanks for listening! I am futurist and science
fiction author John Michael Godier currently musing about alien civilizations again.
Big surprise there indeed. We’ve all heard the rumors about Roswell and crashed UFOs,
but my question is what if an alien civilization came into possession of something we built. Could
there be an alien civilization out there back engineering a downed ‘85 Lebaron they stole
and bringing it back into production? One can only dream and be sure to check out my books at your
favorite online book retailer and subscribe to my channels for regular, in-depth explorations into
the interesting, weird and unknown aspects of this amazing universe in which we live.