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Archive for the ‘Penumbral’ Category

T is for…

T is for Timey-Wimey

I’ve always loved the ‘timey-wimey’ stuff, both in fiction and in science.  It’s something so basic, part of the structure of reality, yet the more closely you examine it, the stranger time becomes.  This is kind of a long winded blog post, and it has a lot of equations in it, which some people find scary, but if you bear with me you’ll find the brain-‘splodey cool bits.  Full disclosure – it’s not my field of expertise, which means there are undoubtedly parts where I’ve run off with the ‘shiny’ and ignored the actual point.  Just doing the best I can with what I have…

Science

Relativity

The first, most well known, source of scientific temporal weirdness is Special Relativity.  Everyone knows (or at least recognizes) the basic equation:

MC2

We’ve all heard that this leads to ‘time dilation’.  The formula for time dilation is:

time dilation If v (the speed the object is moving) reaches c (the speed of light in a vacuum) then you have a divide by zero error, infinite energy, basically that doesn’t happen.

If v is less than c then your denominator is less than 1, and the two ts don’t match.  Your two ‘observers’ experience different amounts of time between the two observed events (whatever they happen to be).

FTL (Faster Than Light)

Now SF fans will often tell you that if v is greater than c the two observers will perceive time as going in opposite directions.  You can’t blame the SF fans for that, it comes from a vast simplification that scientists often give about why they don’t pay attention to those values.  If you actually look at the numbers, though, you’ll see that when v exceeds c (so your observer travels faster than the speed of light).  This isn’t a negative number, it’s an imaginary number.

imaginary

Now, imaginary time evokes a lot of really fascinating imagery, but what it refers to here is a mathematical term –  a temporal axis which is at a 90 degree angle to regular, everyday time.  It’s a lot simpler to see why physicists shake their head at FTL (Faster Than Light) now, because while going backwards in time has an obvious, physical meaning, going sidewise in time doesn’t.

STL (Slower Than Light)

There is a way that physicists do think relativistic time dilation can produce time travel.  It involves combining high speed travel and Wormholes.  Wormholes are a quantum phenomenon which link two points together without traveling through the intervening space.  Scaling the quantum wormhole up to a usable size would involve the use of materials which have properties never yet observed, yet entirely consistent with known physical laws.  The details are left as an exercise for the student, but if such a thing could be found or created, and if one end could be put on a space craft and accelerated up to relativistic velocity then returned to earth, going through the wormhole would give you time travel. One limitation would be that the earliest you could travel to would be the point where the timehole was established.  Still pretty cool.

Quantum

Time travel on the quantum scale is pretty much trivial, because if you’re observing on the quantum scale there’s no way to tell which way time normally flows anyway.  As far as I know, every quantum reaction is completely reversible.  In other words, if you were able to film quantum events, and play the film backwards, it wouldn’t look any weirder than playing it forwards.  Personally, I think this is the least weird thing I’ve ever heard about quantum physics, but it does lead us to an interesting question…

Classical

The second law of thermodynamics states that in a closed system entropy will increase over time.  This basically gives us “time’s arrow” – time moves towards greater entropy.  This just seems to be natural, but given that it’s not observed on the quantum level it could be a ‘local condition’ thing.  In the past entropy was so remarkably, blindingly low that it just had to increase from there, but in the future, when the base level of entropy will be higher, maybe that won’t hold true.  What will time look like then?  What will the world look like then?

String Theory

Not surprisingly, this gets even weirder.  First of all, string theory isn’t really a theory.  It’s more of a model kit which looks really promising to build a hypothesis which might conceivably connect the classical, relativistic and quantum equations which describe the world.  In other words, it might become the “Unified Theory” Einstein never found, or GUT (Grand Unified Theory) as it’s more often called these days.

In string theory space-time is made up of the vibrations of really tiny (Planck scale) loop like particles.   Let me repeat that – the vibrations make up space time.  So what are they vibrating in if it’s neither space or time?  String theory also consists of ten (or eleven) dimensions.  Four of which are big (three space, one time) and the others loop around themselves.  It’s possible that space and time loop around themselves as well, but if they do it’s a really big loop.

So there are a lot of people playing around with string theory.  I seem to recall, years ago, a paper hit PlosOne which proposed a version of string theory with two temporal axis.  I can’t seem to find that link any more, so maybe it’s been lost in the sea of peer review.  Which would be a shame, because not only is is super cool, but it puts FTL back on the map, as it were…

Fiction

I love time travel stories as well.  I’ve talked about Doctor Who here before, but there are so many great fictional universes which play around with time travel in one way or another.  Some are super cheesy, some are tragic, some hilarious, and all of them wonderfully weird.

Definitely a rabbit hole worth falling down…

 

 

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O is for…

O is for Octopus

Haeckel OctopusObservant readers of this blog might have noticed that I like octopuses (octopodes? octopi?).  There’s even one on the banner.  I’ve just cast on a small, tentacled bag which represents either an octopus or a generic tentacled horror which is inspired by them.  The truth is, I’ve really loved cephalopods since I performed a squid dissection in a college zoology class and saw the neural cluster which surrounds its esophagus.   Its brains surround its throat, how cool is that?

Octopus  at Pona do Ouro, Mozambique #SCUBA #pictures #underwater

Octopus at Pona do Ouro, Mozambique #SCUBA #pictures #underwater by Derek Keats, on Flickr

This is probably at the heart of it all.  The octopus (and possibly the squid, though that’s harder to show) are as close to an alien intelligence as we’re likely to encounter without leaving the Earth.  There are other animals which are about as intelligent – ‘greater’ primates, cetaceans, elephants, pigs, crows/ravens and parrots are  of a similar level.  Notice what all the others have in common?  All the rest are vertebrates.  Even the birds are much more closely related to us, evolutionarily speaking.You may have heard many discussions of octopus intelligence.  If not, just hop over to the Cephalopod page and read up a bit.  Always remember that these creatures only live for a few years.  Imagine what they could become if they lived as long as we do.

OK, so they’re cool, they’re smart, they’re also really, really pretty and graceful, in an alien, slightly creepy sort of way.   Clearly they’ve been involved in Japanese erotic art for centuries.  I decided not to run the images here, but look for the “Dream of the Fisherman’s Wife” for a famous example, or search for tentacles in anime…

Knit the Bridge

Knit the Bridge by Jason Taellious, on Flickr

What’s not to love?

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C is for…

C is for Chiropractor

So I’m midway through a course of chiropractic treatment.  As I’ve mentioned before, I’m definitely skeptical when it comes to ‘alternative’ medicine.  I would never consider consulting a chiropractor for (say) cancer or asthma, I’m going because I have recurrent episodes of neck and upper back pain.  I also have migraines and, although this chiropractor claims that the manipulations will help I would not have sought this treatment out for the migraines alone.

I’ve done some research. Found some articles written by a skeptical practitioner, and some double blind studies to figure out what chiropractic can and cannot be expected to do.  Of course, the skeptical source I found claimed that chiropractic treatment was equivalent to ‘conventional’ treatment, while this paper in the BMJ (formerly British Medical Journal) shows that for the particular pain studied, chiropractic was better than standard hospital outpatient treatment (pdf download).    A literature review published in Europe PubMed showed that chiropractic treatment for migraines was fair to very good, but more well controlled studies were called for.

Then there are the studies of risks.  Brian Dunning has claimed that risk-benefit analysis would drive him away from chiropractic.   He has also pointed out that any ‘completely harmless’ treatment for a medical condition is almost guaranteed to be completely useless.  So, I took a look at some actual risk assessments of chiropractic manipulations (the ones without the woo, which are focused on back and neck issues).  The first study, published in Neurology, questioned neurologists in California, and found a certain number of cases of individuals who suffered neurological trauma after chiropractic manipulations.  The other study looked at medicare recipients between the ages of 66 and 99 with neck pain, and compared the risk of stroke between those who sought care from a chiropractor and a conventional physician.  The conclusion was that for the period of observation the differences in risk were probably not statistically significant.

So we’ve got two studies with different conclusions.   Or do they?  The first one establishes a clear correlation between chiropractic neck manipulations and neurological complications.  The second one measures minimal difference in risk between those treated with chiropractic vs other treatments.  So, yeah, there’s a risk.  It’s small.
The course I’ve been prescribed is finite.  I’ve been shown the ‘before’ X-rays, and will have ‘after’ X-rays taken once the course of treatment is finished.  The most ‘woo’ I’ve gotten from the chiropractor is a suggestion to ‘avoid chemicals’ (yes, it did set my teeth on edge, no, I did not challenge it, because it was a single line in the literature and not hit upon).
The last treatment I sought for this was a massage.  It was supposed to be an Ayurvedic massage, but the masseuse conflated the chakras with Catholic saints.  Hey, a good back rub is a good back rub, but the cultural appropriation was maddening.  At least with chiropractic there’s little bit more than 100 years of tradition to mangle…
Is it doing anything?   My husband can feel the difference when he gives me a back rub, and yesterday’s migraine (known trigger, no surprises) never progressed past a mild aura.  So…  maybe.

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