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Saturday, 25 December 2010

An Aetheist's Message At Christmas / Diwali / Hanukkah

If you believe in a god, any kind or any number, then good for you.

Not believing takes just as much faith, trust me.  And placing even a modicum of trust in Science is utterly terrifying...that's why science as a rule is basically paranoia, trying to prove ourselves wrong.

But the one thing I can say is that whatever you believe, whether it's a world created in six days six and a half thousand years ago, or a whole Universe created by a god, or just a very exotic mathematical possibility....well it's pretty darned cool.

The world around us is amazing.  Birds fly more elegantly than anything we've ever seen, waves give us artistic expression from a plank of wood, we're aware of our place spinning through space in the suburbs of a hundred billion galaxies, maybe more.

Yes, we can argue about who, if anyone, made it.  But on a day when that argument is all too divisive, can we not at the very least take a good long look around us?  Even if there's no god, it's still mind-blowingly impressive...


The video repeats a bit, but you get the idea.  We're the only planet with life in the Universe as far as we know.  Hell of a responsibility people/apes/ants/bacteria.  And I make no apology for the music.  Queen rock.  Deal with it.

Merry thingy.
G
x

Monday, 20 December 2010

The Multiverse According To Izzard And Tegmark

You've got to believe you can be a stand-up before you can be a stand-up.  You've got to believe you can act before you can act.  You've got to believe you can be an astronaut before you can be an astronaut.  But you've got to believe.  
Eddie Izzard

Multiverse theory is a funny old thing.  It's one of those theories that might solve a bunch of problems, like the way our Universe seems to be incredibly finely tuned to allow complex life to develop, or some of the oddities of quantum theory like particles being in two different places at once.  It's a theory that has been developed and delved into by some of the most eminent physicists ever to have lived...and it's not even science.

I'm not suggesting, of course, that Martin "Astronomer Royal" Rees, Stephen Hawking, Max Tegmark and their colleagues are cheating in any sense, or wasting their time researching the subject, because it's possible that they're laying the groundwork for a game-changing new theory.  It's still not really science though...yet.

Suggesting that there is such a thing as "a Multiverse theory" is a little over simplistic and disingenuous.  There are a great many Multiverse theories.  Tegmark's work alone suggests there are at least four different possible "layers" of Multiverse, any combination of which could be correct.

There's the simplest kind, level one, which suggests that our normal, everyday  Universe is in fact infinite, or at least far, far bigger than we presently observe.  If you're sat in a boat on a calm sea with your eyes around two metres from the surface of the water then you can only see about five kilometres in any direction...the Earth curves away, limiting how far you can see.  We have the same horizon problem with the Universe, except it curves away in time.
The CMB: The furthest we can see.
The best we can do is see around 45 billion light years.  There might well be more beyond this horizon, we just can't see it.  The picture on the left is the Cosmic Microwave Background, or CMB, the echo of the Big Bang.  In even simpler terms, it's a picture of our three dimensional horizon, and the tiny, tiny ripples in it.  There have been some suggestions recently that small anomalies in the CMB are the result of more "stuff" beyond our cosmic horizon.  If our Universe does, in fact, go on for ever then the chances of there being another version of the Earth somewhere out there become almost certain.  In fact it's relatively easy to work out how far away the other version is likely to be...it's somewhere in the region of ten to the ten to the twenty nine metres away.  That's a ten with 100,000,000,000,000,000,000,000,000,000  zeroes after it.  Quite a long way.  There's an entire alternate Universe almost identical to ours, complete with the same constellations and galaxies and large scale structures a bit further away, ten to the ten to the one hundred and fifteen metres.  I'm not even going to try typing an estimate to that, it's a big number.
  But the horizon problem still exists.  Currently we have no way whatsoever of exchanging information with bits of the Universe beyond our cosmic horizon, other than (possibly) very short range glitches in the CMB.  The main feature of a level one multiverse is that it's all part of the same Big Bang - everything is based on the same laws of physics as our little "local" bit.

The second level is where things start getting a bit weird.  It suggests there are other "post-inflation bubbles".  In essence, other Big Bangs which took place somewhere else.  The laws of physics are the same as ours, but the physical constants will be different.  Gravity might be stronger, probably resulting in a rather spectacular, short lived universe full of black holes.  Or weaker, meaning few, if any, stars and very little other than Hydrogen and Helium.  Atoms themselves may behave differently, or never form at all.  A level two Multiverse is an attractive idea because it naturally solves the fine tuning problem.  There are around forty constants in physics, numbers that are the same everywhere we look.  The charge on an electron is the same anywhere in our Universe, but there's no good reason why it has the charge it does.  If it was different then the laws of physics would still mesh together perfectly well, the Universe would still exist, it would just be different.  Life as we know it almost certainly wouldn't exist, but that doesn't really matter.  In fact, change any of the forty-odd constants by just a little bit and the chances are that any kind of complex structure, including life, couldn't exist. So why is our Universe so delicately balanced?  So subtly "designed"?
  The level two Multiverse solves this problem.  If there are an enormous number of universes, each with its own set of physical constants, then there's bound to be a few that by sheer fluke hit the right combination for life.  Life eventually evolves in this small subset of universes and sits there wondering why its universe is so well designed...

Level three is based on the weird results of quantum theory.  One of the founding experiments is called Young's Double Slit.  I'll let Mark Everett (of rock band Eels) explain:

Why is a rock star talking about a two hundred year old physics experiment?  It's because his father, Hugh Everett III, was a physicist who suggested that this experiment shows two parallel universes overlapping.  The only difference between "our" Universe and the parallel one is that in ours the photon went through the left slit, and in the other universe it went through the right.  Because the two universes are otherwise identical there is a certain amount of leakage between the two, they are able to very subtly influence each other, resulting in the interference pattern.

Everett's "Many Worlds" interpretation was fairly roundly rejected by the rest of the physics community when he first suggested it, and you can see why.  It really does sound like something from a science fiction novel.  The idea is undergoing a little bit of a renaissance however.  The modern interpretation is that all possible moments in time, in all possible universes, actually exist, and ours Universe is simply a "most likely" path through this higher level of Multiverse.  It explains the probabilistic nature of quantum mechanics, the slightly fuzzy nature of the Universe when we take a very close look at it...we're looking at a collection of possible universes, not our Universe at all.
  Again, there's no real way to test this satisfactorily.  There is the quantum suicide experiment for example.  The experimenter stands in front of a machine gun which is connected to a device which measures the spin of a subatomic particle.  The spin can be either up or down - if it's up then the gun fires, if it's down the gun doesn't.  If Everett's idea is right, and does actually represent a Multiverse, then there will always be a universe where the experimenter survives.  If the measurement is done ten times then there will be 1023 universes where the newspaper headline is "Idiot Scientist Shot In Face" and one where the experimenter survives.  Unfortunately (for the theory, if not the experimenter), there is always exactly the same small chance of survival (even if the Multiverse idea is wrong, so you can never have a definitive answer.

Tegmark's last level, the fourth, is the most philosophical in nature.  All of the previous levels share one thing in common, the laws of mathematics.  Even if the laws of physics change, they can still be described with equations and mathematical expressions that would be recognisable to us.  Changing the universal gravitational constant, G, changes the universe.  A level four parallel universe changes the equation that G appears in.  Currently there are no known ways, even theoretically, that this idea can be physically tested or explored in any way.

Tegmark's ideas are by no means the only ones, but they are a popular basis for investigating the nature of a Multiverse if it exists.  No, none of it makes testable and new predictions at the moment, so it's not science yet.  The implications, on the other hand, are fascinating.

If an infinite Multiverse of any kind exists then we can have some fun with it.  Let's take a lottery for example.  It's intuitively obvious that you have to buy a ticket to win, but if we're in a Multiverse then that statement changes slightly...buying a ticket guarantees that you win.  Or at least one version of you, somewhere.  You're also immortal.  Whatever happens that might kill you, there's always a version that survived against the odds, and as you're able to read this, you are that immortal version...so far at least.  The flipside is also true.  Every time you cross the road there's a version of you that is killed.  Gerry, my flatmate, has taken this principle to a humorously logical conclusion: he delights in setting small traps for me that have a tiny, miniscule, theoretical chance of killing me.  He reasons that every time he does this he gains the satisfaction of knowing he's killed me in a parallel universe, without all the drawbacks of being arrested and later murdered in prison.  He's an odd man in many ways.

So within reason anything is possible in a Multiverse.  But there's no short cut, you can't just sit back and expect to win the lottery or become an astronaut or even a stand-up comedian.  The universe where that happens is one where you bought a lottery ticket, or studied physics, or died at umpteen comedy clubs first.  You have to make sure you're in the right universe, which means you have to put the work in.

But first, you have to believe.

Monday, 6 December 2010

Just remember that you're standing on a planet that's revolving...

Just remember that you're standing on a planet that evolving,
     Revolving at 900 miles an hour.
 There's a little poetic license in Monty Python's classic, it's actually just over that, closer to 1040 miles an hour at the equator, but only six hundred-ish up here in Edinburgh.  900 works well enough though, and it scans nicely.

So yeah, we're spinning.  We all know that, like night and day.  The Earth spins, the Sun comes up, the Moon does its thing and some people even bother about the stars if they're out late enough.

Most of the time I'm worrying about the sky spinning around it's a result of some nice new guest ale in the Blind Poet, but just sometimes you get a rather literal demonstration.

This is a picture of Jupiter, plus (right to left), Europa, Ganymede and Callisto.

That's taken with a digital SLR (Nikon D100) on a telescope mount and a 270mm lens.   It's a bit out of focus, and there's either a lens flare or a galaxy to the lower right of Jupiter.  The main feature though, is the trail.  The tripod and camera were locked down, the sensor was set to delay until after the vibration had settled....it's not all my fault, honest.  It's not even a particularly long exposure, only two seconds.

That's how fast we're spinning.  Jupiter is whizzing past...or we're whizzing past Jupiter, depending on your reference frame.

The main point is that I took a photograph of Europa, the ice moon from 2001.

All these worlds are yours.  Except Europa.  Attempt no landings there.
 They didn't say anything about photos did they?

Friday, 3 December 2010

What The NASA Announcement Actually Means

The weird thing is, the message got swallowed in the argument over its importance.  But that's another post.

Here, in fairly plain language, is what it means:

They've probably found an extremophile.  Bacteria are remarkably resistant, they appear in sub-zero temperatures, high acidity, high temperatures, high salinity, all sorts of places.

Now we've found one that not only survives a high-arsenic environment, it can actually survive without phosphorus at all.

Yup, that's chemistry mumbo-jumbo to some.  In essence, phosphorus makes the backbone to DNA, it's the chemical foundation of every single living organism on the planet.  Technically, in the known universe.  Every living cell has a strand of DNA made with a strand of phosphorus.

Arsenic could do the job though.  The chemistry works.  You can, in theory, have arsenic based life, and until today it was in exactly the same category as the "silicon based life" so beloved of science fiction.  It was fiction, unsupported theory, hypothesis.  Until today.

Today a very clever scientist (with a great website) announced that she'd diluted these bacteria down until there was no phosphorus left in the system.  The bacteria were operating on an arsenic based genome.

Now, herein lies the rub: where does it come from?  No, of course it's not extraterrestrial, but is it the same as phosphorus based life?  In this case, it seems it is.  It looks like a case of normal, everyday life adapting rather spectacularly rather than a new form of life (the "shadow biosphere" that has been suggested).

Either way, NASA were absolutely right to announce this as a discovery of significance to astrobiology.  One of the following things have just been demonstrated in some style:

  • Life based on a fundamentally different chemistry is not only possible, it actually exists!

  • It might be the second spontaneous emergence of life ever observed by humans, with implications for the odds of life elsewhere.
  • It might just be normal, boring, tedious Earth life surviving in ridiculous circumstances.  Ones which are based on fundamental chemistry, suggesting that life can survive a far greater range than we previously gave it credit for, and echoing some (so far speculative) ideas about potential biochemistry for Titan, Enceladus and Europa to name a few we've already visited.

There was a lot of hype and expectation, but the fact remains, this is a highly significant breakthrough in both biochemistry and astrobiology, and has been led by the astrobiologists.  This is a big discovery for a young field which carries some important answers about the nature of life.

Wednesday, 1 December 2010

NASA Astrobiology Announcement - Wild Rumour And Conjecture

NASA issued a press release today.  Possibly something big.

There's going to be a public statement on Thursday afternoon (UK time) which will: "impact the search for evidence of extraterrestrial life.".

Now let's be very clear about two things:
  1. Astrobiology is a very young science.
  2. Astrobiologists have been a bit busy in the last couple of years.
This could be just another "Big Science Announcement" (BSA) designed to attract some publicity - and nothing wrong with that, science is cool and we should gossip about it a bit more - but it could possibly be something more.

NASA are being rather taciturn over the actual contents of the announcement, as is their right with any BSA.  However, this much is known -- the announcement involves a very special group of people.  The listed "participants" are all people with a very high level interest in astrobiology.  Interestingly, they all seem to fall in to two of three particular camps:

  • People who have suggested that we search for a "shadow biology" on Earth, to test how likely spontaneous life generation (biogenesis) is, and also to look for signs of panspermia.
  • People who have worked on the wonderfully successful Mars missions in the last couple of decades, from which geological data is the main thing we have.
  • People who have worked on desert varnish.
 Desert varnish is the clincher for me. It's odd stuff.  It's kind of a sheen that certain rocks get in very dry environments, hence the name.  It looks like it's been painted on, but in fact it's entirely natural, it just isn't biological.  It looks like lichen, it seems to grow like it, but it's not got DNA or anything like that, it's more like a mineral growth than life.

And see that first bullet point?  One of the participants in this BSA, Felisa Wolfe-Simon, published a rather influential paper last year which suggested that astrobiology should be looking for the Earth's "shadow biosphere".  The idea is that if life can develop, and if it's likely to happen, then it should have happened here on Earth more than once.  We might just not have spotted it...

Seriously, look how obsessed we are with DNA and proteins and the whole "organic" thing.  We might not spot a different kind of life if it was sat under our noses, is what Wolfe-Simon's paper suggests, and what's more, let's start looking.  And like I said, the paper was rather influential, which means people started looking.

And now some of the people who looked are standing up with her and NASA and they have something big to say.

Oh...did I mention that NASA found desert varnish on Mars years back?

So we have people looking for new life, plus something that looks a lot like life but isn't, and also exists on Mars.



Long story short?  Blogger makes wild suggestion that (possibly Silicon based) life has been found on Earth and may well also exist on Mars.

This will rock if I'm right....

Saturday, 27 November 2010

Cassini Set For Enceladus Flyby

Our Solar system, the Sun and all those who sail with her, is pretty ordinary as far as we can tell.  There's a very average star surrounded by a few gas giants, some small rocky types and a fair bit of rubble.  Examinations of other stars have so far shown much the same setup and there's no reason to suspect our system is anything other than fairly mundane, with the possible exception of some interesting biology on the third rocky type.

And yet we still find fascinating things everywhere we look.  One of the funkiest ongoing projects is the Cassini Equinox Mission, a space probe orbiting Saturn and paying some flying visits to the attendant moons.  Cassini has been producing some stunning data over the last six or so years, some of it highly technical, and some of it simply very, very pretty.
Based on an original from NASA/JPL (cropped by author)

This, for example, is Enceladus, an ice moon with a diameter of about 500km.  There are two particularly interesting things in this image:

The stripes and flat areas are the first.  Look at almost any object in the Solar system that doesn't have a thick atmosphere (which Enceladus doesn't) and you'll find one main feature: craters.  Big craters, small craters, overlapping craters, craters inside craters...there's usually lots and lots of craters.  Everything in the Solar system is being constantly bombarded by lumps of rock, ice and metal left over from the original formation, and that leaves a few scars.  Even the Earth has a few big ones from objects that made it through the atmosphere.  Enceladus has craters too, but not as many as you'd expect.  There are big areas which are fairly crater-free, meaning that the surface is being wiped clean somehow.  The stripes are a clue as to how this is happening.

The second interesting thing in the picture is the fuzzy plume at the bottom of the picture.  Enceladus is too small to hold an atmosphere down, so what is the plume, and where did it come from?

The most likely solution to both curiosities, the plumes and the unusual surface, is that Enceladus isn't entirely frozen.  The suggestion is that under the surface shell of ice there is liquid water, possibly huge amounts of it.  The current theory is that because Enceladus' orbit isn't perfectly circular it's kneaded by Saturn's gravitational pull.  If you take a snowball, stick it in a plastic bag and crunch it about in your hand it'll melt fairly quickly, and that appears to be what's happening with Enceladus.  And a liquid ocean under the ice would produce tectonic activity very similar to what we see on Earth.  The icy crust will slide about on the water, crack open, melt and refreeze, potentially explaining the lack of craters.

This is where this article becomes a bit speculative.  There's no suggestion that there's life anywhere in the known universe other than on Earth, but we do have a few likely candidates:  hardy microbial life on Mars perhaps, or possibly even some funky methane eating organisms on Saturn's gigantic moon Titan.  One of the best bets however, is anywhere you find liquid water, which puts Enceladus firmly in the "just maybe" category.  We've got life on Earth which exists in a very similar environment, under the Antarctic ice cap for example, or deep in the ocean.  There might be nothing - Enceladus might just be a dead snowball hovering too far from the Sun.  The potential is certainly interesting though.

Cassini will be making another close pass on Enceladus this Tuesday (30th November, 2010), skimming past at a mere 48km.  Even if there's no extraordinary new game-changing data from the plucky little space probe, we should at least get some very pretty pictures back.

Tuesday, 23 November 2010

The PiSBN Project

[Jan 2015 update - thanks to Cliff Pickover for an unexpected Twitter boost to an old article - I should point out that his books on maths and science are excellent, I used to deal with them a lot as a science buyer at Blackwell's.  See also a followup at the end on ISBN10]

I don't normally apologise for being a bit of a geek.  There's a part of my brain that's into computers and space and science and all that, it's just the way things are.

But to be honest, even I cringe a little at my latest little project.  Sorry about this.

Pi is an interesting number.  It goes on forever, doesn't repeat itself, and appears to be entirely random.  And in an infinite, random sequence, you get every possible combination of numbers eventually.  Your phone number is in there somewhere.  And every book written, if you convert the numbers into ASCII.

Searching Pi for books like that would be stupid though, you'll burn up the best computers on the planet before you get anything worthwhile.  There is, however, a quicker alternative.

Almost every single book published since 1966 has an ISBN number.  These days they all start 978, then there's another ten digits.  The last one's a check digit made by multiplying the others up in a certain way.

So I wrote a program that searches Pi for ISBN numbers.  Then it checks them to see if the check digit is a valid one.  Then it looks the ISBN up on Google Books.

I got three hits in the first fifty million digits of Pi.  It took about ten minutes.  Actually, it took about three hours to write the thing properly, another hour debugging it, and a frustrated lie in the bath half way through.  And about six cups of tea.  Once it actually worked it was fairly quick though.

And so, ladies and gentlemen, I present for you edification and entertainment....

The first three books in Pi!

(Cue fireworks.)

At the four hundred and nine thousand, seven hundred and eighty third decimal place, we have:

Licentiate seminar on environmental engineering and biotechnology
by the Tampereen teknillinen korkeakoulu. Bio- ja ympäristötekniikka.
(Tampere University of Technology. Department of Biological and Environmental Engineering.) 

I have to admit that I haven't read this one, but I'm quite chuffed that the first book (well, journal) is something a bit geeky.


In second place, at the two million, one hundred and twenty thousand, two hundred and fourth place, is:

Sneeuwwitje en Rozerood
by Jacob Grimm


Or as it's known in English, Snow White and Rose Red.  And because the original is not covered by copyright you can get a copy from the excellent Project Gutenberg.  Not hugely geeky, but there is something wonderfully gothic and conspiratorial about one of Grimm's turning up.

And taking the bronze, at the three million, six hundred and thirty thousand and thirty third decimal place:

The healing knife
by George Sava

A curious sounding book written under a nom de plume by a "noted Harley Street Surgeon".

I'll bet you feel better now that you know what the first three ISBN numbers are in Pi?  I know I certainly do.

Sorry again.


2015 Followup
Bookish types will have recognised that I searched for ISBN13 versions - and that there's also a 10 digit version which was used until 2007 (coincidentally when I first worked as a bookseller, and witnessed much gnashing of teeth from people who had 40 years experience as booksellers or, worse, software suppliers to the book trade).

The 13 digit version was brought in to align the whole system with an over-arching barcode, the "978" was added to denote "bookworld" - books, magazines, journals, that kind of thing. Unfortunately, it also screwed with the check digit at the end, meaning that also had to be recalculated.  As a bonus, however, the new check digit could only be 0-9, while the ISBN10 version could also have a check digit of "10" which was encoded as "X".  This is the main reason I went with ISBN13 in my search, Pi doesn't contain any X's.

However, a search for ISBN10s would be far more profitable in terms of books discovered, even ignoring the missing ones with X's at the end. A quick and dirty guess would suggest thousands of times more, and now, the internet being what the internet is, somebody has run with it in a glorious way.

David Fiander has found a total of not three, not thirty, not three hundred, but 1,168 books in the first million digits, and he's posted a great big spreadsheet with all of them on it on his blog.  My thanks to him for turning this from a geeky little project into a geeky bigger project.

Tuesday, 2 November 2010

Trying to explain the weirdest idea in the universe.

This is going to sound utterly crackpot.

Sorry, but some of the big ideas can sound a bit weird.  To an atheist, the idea of a god seems a little out-there, and this is the flip side - an atheist suggesting something about the universe that not only might never be proved, but might not even be provable at all.

Or even wrong.

But hey, the whole ethos of science can be summarised by "I might be wrong, but what about...?", so I'm going to throw this idea out there and we'll see where we go with it.  So here we go, hold on tight, this is the big soundbite:

Mathematics might be real.

It's an idea that I've been throwing around in my head for a few years now.  It all started with physics, a subject which has been close to my heart since I first wondered just what the hell was going on.  For some reason physics seems to be very good at taking the stuff we see around us and distilling it down to a simple mathematical equation or, at the very least, one prefixed with "In a frictionless vacuum".  See, for example, gravity. 

Courtesy xkcd, prescient comedy god amongst men.

Drop any object, near any other object, anywhere in the known universe, and we pretty much know what's going to happen.  Newton got it right enough for everyday use, and Einstein's relativistic reinterpretation corrected Newton well enough to not only change our view of the structure of space and time, but also to run atomic clocks in orbit decades later.  This one little idea, using nothing mathematical beyond primary school maths (if the idea of a square root is still primary level) describes the vast majority of what happens in the range of any telescope we have.  One equation describes most things we can see.

Or let's take something else, like things bumping into each other.  Again, Newton laid the groundwork, and then James Clerk Maxwell refined the ideas with his theory of electromagnetism, and another huge lump of the universe was reduced to an equation.  Well, maybe three, but there's a lot of stuff in the universe.

By now things are starting to look a little suspicious.

It seems that everything we experience is a rough estimate (a fact that's easily demonstrated by a high speed cameras or electron microscopes), and that the closer we look the simpler things become in a way.  Take, for example, a book.  Prop one up on the far side of the room, as far away as you can.  Go on, I'll wait..

...so, there's a book.  You can see that.  I'm sure you're well aware that it could be an optical illusion by a talented artist, but if you move around the room a little you'll prove to yourself that it's a real 3D object.  But it could be a clever film prop, so you can pick it up and flick through to convince yourself it's a real book.  Is it really the book it claims to be on the cover?  Well, read it and find out.

All of the time you're gathering new information, and yet the object you're observing becomes more simple.  As you look closer you see:

  1. An object that looks like a book, but could be a million other things.
  2. An object that looks like a book, or a very good effort at one.
  3. A book, one of countless billions.
  4. A book, by a specific author.
  5. A particular book by that author.
And so on and so forth.  As you look deeper and deeper you'll find a very small ASCII text file embedded on a paper based medium - a blank book plus an ebook.  Then you find yourself looking at molecules arranged in a particular way.  Then atoms.

When you get down to the subatomic level you're saying, in effect, "there's a quark here".  A quark can be described with just three numbers: the mass, the charge and the spin.  That's it.  You don't get big quarks or little quarks, you can't get a quark made from metal and a quark made from wood, you only get three numbers.  That's all a quark is, just three numbers.

Now we're not looking at a thing at all, just three numbers.  Add to that a few rules about what happens when these three numbers bump into another three and you're got something called quantum mechanics, and yes, it's really that simple.   Well...nearly.  The maths is a little tricky, but particle physics and quantum theory are both in effect just careful juggling of a few numbers, not objects.

It may be that we just don't know enough yet (see above, "science admits it might be wrong"), but it all seems to boil down to numbers.  Not objects, just numbers.

What we're looking at now is commonly called Platonism, after Plato's idea that maths is real, and that's absolutely what I'm supporting here, the idea that mathematical ideas are real in their own right.  We know Pythagoras' Theorem, and yet we're not able to build a mathematically perfect right-angled triangle.  We can get really close, but the best we can even theoretically manage at the moment is a triangle of Planck lengths - three by four by five of them.  And even then, it's still a bit hazy.  Maths is more perfect than reality can muster, but reality seems to be trying very hard indeed.


See, told you this was a bit of a wacky post.


For further reading, without much terminology and maths, see:

The Unreasonable Effectiveness Of Mathematics In The Physical Sciences
Eugene Wigner - a classic and readable academic paper on the subject, link courtesy of Buffalo State College, US

 Anathem
Neal Stephenson - a work of fiction covering the main themes and a beautiful work at that.  The inspiration behind this post in a way.

Tuesday, 12 October 2010

Everybody wave to 2010TD54!


One of the nicest thing about the web is the way that it's still being used for freely shared information, particularly among academic and research groups as it was originally designed for.  NASA are one group that are particularly good at producing some really interesting stuff for everybody, from pretty pictures to proper orbital data.

And just sometimes, that orbital data says something a tad out of the ordinary.  This image was generated by a website belonging to the Jet Propulsion Laboratory, the people who brought you the glorious Cassini-Huygens mission.


The two yellow lines are just there to show where the Sun is, and to give a sense of perspective.  Then you can see the orbit of Mercury looping around it, and Venus, Earth, and the last white line is part of Mars' orbit.

Then there's the blue line.  The dark bit is where it's been, the light blue bit is where it's going.  And yes, it's a bit close to the Earth. 

2010TD54, meet the Earth, and all who sail on her.  Earth, meet 2010TD54, a fairly small asteroid that's about to get a bit intimate.  Feel free to blow a kiss as it whizzes by.

The image, in fact, shows TD54 a bit further out on Oct 11th, the closest approach is around 10:49 GMT (11:49 BST) on Oct 12th.  It's going to be very close in astronomical terms, around about 45,000 km in fact, which is a whisker.  If we ran a rope around the equator twice then it would be long enough to reach.

Don't Panic.  TD54 is only about 6m across.  Its kinetic energy is equivalent to roughly one percent of a megaton of TNT, similar to a very big conventional bomb or a very tiny nuke.  Even if it hit, which it won't, it would be unlikely to do any serious damage; maybe destroy a few houses, but more likely just burn up in the atmosphere.  In fact, it's a significant technical achievement to find and track something that small before it's passed us by.

Saturday, 9 October 2010

The Sun, a drunkard's walk and some Python...

I've been playing around with Python recently - the programming language that is, not the snake.  (Snakes are cool too though.)  One big difference with Python as opposed to PHP and Perl, the languages I normally use, is that Python is a little more geared towards graphical simulations rather than simply playing with a text input/output, especially with the pygame modules installed.  Coming from a physics background, an obvious starting point is to try simulating some simple particles and maybe some gravity.

I had a dig around and found this script by Niels Stender which does exactly that, in a fairly elegant way.  I find that tinkering with somebody else's code is a good way to get to grips with the syntax and style of a language.

Stender's code simply generates the particles and the relevant physics and starts them running, it's a good estimation of how particles behave in a gas, anything from the Earth's atmosphere to the interior of the Sun.  There's a classic fact that gets trotted out in many astrophysics lectures: it takes around a million years for a photon to get from the centre of the Sun to the surface...and photons travel at the speed of light.

Why so long?  Well the photons bounce around a lot, like the particles in this simulation.  The way they bounce around is random, like tossing a coin.  Toss a coin a thousand times and you'll get roughly 500 heads and 500 tails - the equivalent with our photon is that it stays pretty much where it started, at the centre.  The odds of it reaching the surface of the Sun are very small, it would be like tossing a coin a thousand times and getting a thousand heads...which is why it takes so long, the photon has to wait for something very unlikely to happen.  This process is known as a random walk, or slightly more poetically, a drunkard's walk.

Which is where my addition to the code comes in.  I fancied tracking one individual particle, no different to any of the others (except it's red, just to make it more visible) and recording the x coordinate.  Over time my code builds up a graph of the red particles position, which should, if the code and theory are correct, closely resemble a Bell curve, or a normal distribution pattern.  This shape pops up everywhere from population biology to the most fundamental quantum theories, it's a mathematical signature showing that something truly chaotic and random is happening:


Here's some video of my script running....

And now here's the same simulation, ten minutes later.  The graph in the bottom right is a reasonably good fit for the Bell curve, hooray!



You can have a tinker with the code yourself if you want - the source code is here. You'll need to install Python and pygame, both of which are free, if you don't have them already.

Thursday, 30 September 2010

Fermi Problem: The Day The Music Dies

A Fermi Problem, in case you've not heard of one, is a bit of a game really.  It's a riddle in a way, a question that generally asks for a rough estimate to a technically very difficult problem.  You're not expected to be get the right answer, in fact for many problems if you're within a hundred times the right answer then it's pretty good.  Not to be confused with the Fermi Paradox (same Fermi, different quandry) which is related to the existence or otherwise of extra-terrestrial life.

The point is to show your working.  That's the interesting bit, come up with a wild guess, but base it on a few real life factors.

So my problem is this:

Music is finite.  If you're fairly strict about the standard rules of western music and the range of human hearing, then there's only so many combinations of notes.  "All the tunes possible" is a very big, but finite set.

If humans continue writing tunes and expanding at their current rate then when will we have used up all the music?


Obviously, you could just make the tunes longer and longer to get more and more of them, so I'm also going to place a time limit on "All the tunes possible": you've got a maximum tune length of nine minutes forty eight seconds.  If it was good enough for Bat Out Of Hell it's good enough Fermi.

Hit the read more link for my proposed answer...


Wednesday, 29 September 2010

Mice, Chickens, Eggs & Evolution

I'm being out-evolved by something living behind my fridge. We've got a mouse in the flat. It's no big deal, the Old Town of Edinburgh is swarming with the blighters, the place is a six hundred year old labyrinth, bridges have been built over streets, covered up, filled in, tunnelled through, it's a mouse paradise. They're not usually much bother - the bleepy deterrents normally do the job, and on the rare occasions when they get a bit overly courageous we put down poison. No, it's not the kindest method, but it is one of the few that works on Old Town mice, and kinder than those sticky traps.

The mice, however, seem to have got wise to it, the poison doesn't work anymore. Actually, that's not technically accurate. I'm sure the poison still works, the mice just aren't falling for it any more. Not because they know it's poison of course, they don't, the absence of very small toxicology textbooks is all the proof I need of that. They're just not touching the stuff any more. What must have happened is that sometime in the last couple of years there was a community of mice. Most of them liked blue coloured grain, they took it and ate it and died hopefully peaceful deaths from hypothermia. A couple of them didn't. For some reason or another they didn't go for the free food. Maybe it was the smell, maybe the colour, maybe they just didn't like the taste - maybe they're refined mice and expect more presentation than a small plastic tray. For whatever reason, they didn't eat it. So most of the mice died...but a few survived to have baby mice. The baby mice inherited their parents' dislike of the grain we put down, so they don't touch it either, and they have more babies, none of who are partial to warfarin laced wheat.

Nothing has changed except the fact that the humans are a weapon down in the ongoing struggle for Old Town domination. The drugs don't work.

So if anyone doubts evolution, I've got some mice you should meet.



Speaking of evolution, which came first, the chicken or the egg? It's a bloody stupid question. Ever since I was a kid I've hated this one. The fact of the matter is, the egg came first, end of story, argument over, you're very welcome.

Firstly, let's go a little further back. There weren't always chickens. There were dinosaurs, and then there was Archaeopteryx, then there were the proto-chickens. Humans began to domesticate these birds and slowly they crept their way towards full-blown chickenhood. Of course, what constitutes full-blown chickenhood is still up for debate - there's maybe one specific genetic tweak that produces some morphological change that defines a chicken, but the point remains: however you define a chicken, there was a first one.

The first chicken hatched from an egg that was laid by an animal that wasn't a chicken. It was very nearly a chicken, in fact you'd probably need to run a battery of tests to confirm that it wasn't a chicken. This nearly-chicken laid an egg. As is the way with the world, the reproduction from adults to offspring wasn't perfect, there were small glitches in the DNA. Most of them did very little indeed, but in this case there was one tiny error in the strand that made the offspring a little different to anything that went before. It was a chicken, the first in a long, noble and tasty line.

And if the animal that comes out of an egg is a chicken then that egg is a chicken egg by definition. The egg belongs to the animal inside it, and that animal was a chicken.

The egg came first, but it wasn't laid by a chicken. End of discussion, game over, QED.

Sunday, 26 September 2010

Total Eclipse Pt II: The Explanation

So what on earth was the last post all about?  Well, you know how it is.  It's Saturday night, you've had some wine and cheese and pate and olives and suddenly you start having "good" ideas.  Yup, sorry, I was drink-coding.  These things happen.

Whilst researching for an 80's themed fancy dress party I came across a stunning piece of work by Jeannie Harrell, a flow chart that generates a section of Jim Steinman & Bonnie Tyler's cult hit "Total Eclipse Of The Heart".

As this gloriously demonstrates, most songs have a structure, bits repeat.  Total Eclipse does this repeatedly, and as such is ideal for a really silly coding exercise, which (if you're not familiar with PHP) is what all that gibberish does.  It generates the entire song using a mere 2366 characters, rather than the 3050 in the official version from Bonnie Tyler's website (not including whitespace).  That's a 22.4% saving on keyboard wear and tear if you ever need to type the lyrics out on a website.

Bat Out Of Hell should also work quite well...in fact, I'm tempted to compile a league table of songs and how compressible they are....2 Unlimited may well end up near the top...





"Total Eclipse Of The Heart" (Optimised Version)

<?php
// TOTAL ECLIPSE OF THE HEART by Steinman & Tyler //
// (Optimised cover version by McGhee & Robbins) //

$short_turn="Turnaround, Every now and then I get a little bit ";
$rabbits="Turnaround bright eyes";
$longturn="$rabbits, Every now and then I fall apart";
$need="And I need you";
$forever="Forever's gonna start tonight<br>";
$time="Once upon a time";
$eclipse="A total eclipse of the heart<br>";

$v1=array("lonely and you're never coming round<br>",
          "tired of listening to the sound of my tears<br>",
          "nervous that the best of all the years have gone by<br>",
          "terrified and then I see the look in your eyes<br>");

for ($i=0;$i<4;$i++){echo $short_turn.$v1[$i];}
echo "$longturn<br>$longturn<br><br>";

$v2=array("restless and I dream of something wild<br>",
          "helpless and I'm lying like a child in your arms<br>",
          "angry and I know I've got to get out and cry<br>",
          "terrified but then I see the look in your eyes<br>");
       
for ($i=0;$i<4;$i++){echo $short_turn.$v2[$i];}
echo "$longturn<br>$longturn<br>";

$chorus="$need now tonight<br>
    $need more than ever<br>
    And if you only hold me tight<br>
    We'll be holding on forever<br>
    And we'll only be making it right<br>
    Cause we'll never be wrong together<br>
    We can take it to the end of the line<br>
    Your love is like a shadow on me all of the time<br>
    I don't know what to do and I'm always in the dark<br>
    We're living in a powder keg and giving off sparks<br>
    I really need you tonight<br>
    $forever<br>$forever<br>
    $time I was falling in love<br>
    But now I'm only falling apart<br>
    There's nothing I can do<br>
    $eclipse
    $time there was light in my life<br>
    But now there's only love in the dark<br>
    Nothing I can say<br>
    $eclipse<br>";
   
echo "<hr>$chorus<hr>";
echo "$rabbits <br>";
$short_turn="Turnaround, Every now and then I know ";

$v3=array("you'll never be the boy you always wanted to be<br>",
          "you'll always be the only boy who wanted me the way that I am<br>",
          "there's no one in the universe as magical and wonderous as you<br>",
          "there's nothing any better and there's nothing that I just wouldn't do<br>");

for ($i=0;$i<4;$i++){echo $short_turn.$v3[$i];}
echo "$longturn<br>$longturn<br><hr>$chorus<hr>";
?>

Sunday, 19 September 2010

How To Destroy The Universe - A Beginners Guide

Firstly, it should be pointed out that destroying the Universe is considered to be a little anti-social in many quarters, and may even be illegal under your local laws.  Please obtain professional legal advice before attempting it.

Secondly, you're not going to need the Large Hadron Collider.  Let's make it clear from the outset: the LHC simply isn't up to the job, and by many, many orders of magnitude.  Using the LHC to do what I'm going to suggest is like trying to set off a nuclear explosion with a small lump of Uranium ore and a toffee hammer, it simply isn't going to happen.

So with the obvious warnings out of the way, how are we going to destroy the entire Universe?  Simply blowing up a star or two isn't going to do it.  In fact, blowing up all the stars isn't going to do it, despite Steven Moffat's best effort in the last season of Doctor Who.  Even if you could make every star go supernova at once, the Universe would still be there...OK, it would be a Universe full of dust and ashes rather that stars, but it would still be there.  We're going to need a much bigger bang.

The bang we're looking for is something called 'vacuum decay', and it has nothing to do with household appliances.  A vacuum, to a physicist, is a rather complicated thing.  It's exactly what you're thinking of - an absence of matter, a space that contains no atoms, no molecules.  In the middle of the last century, however, it became apparent that a vacuum is never really empty, quite the opposite in fact.  A vacuum, even the most perfect one you can imagine, is a bit busy.  There's space and time for starters, and a plethora of 'virtual particles' popping in and out of existence the whole time...on the smallest scales a vacuum is a seething mass of weirdness.

All of this weirdness requires energy - even in particle physics, there's no such thing as a free lunch.  This energy is called, with remarkable clarity and lack of imagination, vacuum energy.  Depending on the theory you use to calculate it, the vacuum energy in a cubic centimetre of space is somewhere between 0.00000000000000000001 Joules and 1x10^107 Joules (a 1 with 107 zeros after it), so it's fairly safe to say there's a certain amount of uncertainty.

(As a point of reference it takes about 35,000 Joules to bring a litre of water to the boil)

Whatever the actual value is, the point is that empty space has energy.  There's no particularly good reason why our Universe has the amount of vacuum energy it does, in fact it could have values far outside our (already uncertain) estimates, and therein lies our method for destroying everything.

Now, not content with throwing some big numbers around, I'm going to drop a graph into the mix as well.  Don't Panic.  If it helps you can think of it as a picture of a rollercoaster.  In fact it will probably help if you do, because I'm going to stick with the analogy.  Here it comes, hold tight....



What this shows is a completely made up graph of the possible amount of vacuum energy in the Universe.  We're the little red dot.  Now, imagine pushing the little red dot to one side or the other...it'll just roll back down to where it started.  Push it a bit harder though, and it'll roll over the peak to the right and settle in a new position in the second, lower dip to the right, and a lot of energy will be released in the process (equal to the difference in height between the two dips).  That's potentially a lot of energy.  If you can push one tiny bit of the Universe, a sphere of just a few hundred metres in diameter, over the peak then it gives off enough energy to push the space around it over the edge, which pushes the space around that over the edge, and you have a bit of a chain reaction on the go. 

The bubble expands at nearly the speed of light, and inside it everything changes.  The very laws of physics, and by association those of chemistry and biology, alter, and not in a good way.

...one could always draw stoic comfort from the possibility that perhaps in the course of time the new vacuum would sustain, if not life as we know it, at least some structures capable of knowing joy. This possibility has now been eliminated. 
Coleman & de Luccia

 Voila, we've destroyed the Universe, at least as far as we currently understand it.  So how do we do it in practice?  Well, we need a very high energy density, something like a very, very big bomb to push it over the edge.  This was one of the "risks" associated with the LHC by people who didn't quite get the numbers (or "twats" as Brian Cox refers to them) - the energy densities created by the LHC are indeed very high, but they're nowhere close to high enough.  How do we know when there's such uncertainty over how much vacuum energy the Universe has?  Well several times a day cosmic rays slam into the Earth's atmosphere with very much the same energy density as the LHC's experiments.  Once a month or so we get hit by a cosmic ray with far higher densities even than that, and every decade or so there's a truly exceptional event which surpasses the LHC by hundreds of times.  None of these events seems to have triggered vacuum decay, after all, we're still here.  (So why have we spent so much on the LHC when nature regularly beats the pants off it?  Well the whole point is, in effect, to take a photo of the event with a very big digital camera, and we never know where and when the natural events will happen.)

Supernova, black holes merging, even gamma ray bursters, the most violent explosions ever observed, have so far failed to tip us over the peak and destroy the Universe, so we're going to have to dream up something else, an even bigger bang.

Which brings us to a curious little post-script, one best illustrated by a quote from Douglas Adams:
There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened.
 What if we're in a Universe where vacuum decay has already happened?  From the inside of the bubble it would look very much like a Big Bang....

Thursday, 16 September 2010

Why "Galileo Was Wrong" is not even wrong.

The American based Catholic group Galileo Was Wrong (GWR) has been getting a bit of stick recently, noticeably from Slashdot, for their assertion that the planet Earth is, in fact, at the centre of the Universe.

A tad harsh I reckon.

Not that I believe their standpoint is right, you understand.  Certainly not in the same context, with the heavy religious slant and subtitle of "The Church Was Right".

But there are some interesting ideas here - questioning established facts for one.  A world where people question their own beliefs is a better one, we should all do it more often.  Are you still voting for the same political party out of habit, even though the policies have changed drastically over the decades? Still buying the same toilet roll that was all cutting edge (no unpleasant pun intended) in the 1980s?  Still (and here's the rub) believing in the same god you were told about when you were six?  There's nothing wrong with believing in a god in my book - all of the major theologies freely admit that it's entirely a matter of faith, and science freely admits that the axioms of whichever branch you take are also based on faith, so there's no real argument there.

The point is, look at your old beliefs occasionally, make sure you're up to date.  There's nothing more cringeworthy than holding an old belief...nope, not even finding out that your boss follows your Twitter ramblings ;)

That's what GWR are doing, looking at an old scientific belief, one which has changed drastically in the last few hundred years.  That's the beauty of science, it changes, it relishes the mistakes.  If mistakes aren't made, then science isn't doing its job properly.

Sorry guys: Galileo's work is still the subject of a great many questions, but probably not in the way you're thinking.

Unless the Catholic Church have some top secret 17th Century documents concerning hyperbolic geometry and imaginary numbers then the whole argument is akin to getting in a fizzy over whether the Sun is kind of a yellowish colour. 

The truth is a bit weirder.

If the Big Bang theory is even remotely correct, if the entire observable Universe was once all in the same place, then yes, the Earth is at the centre of it.  All of the constituent particles were at the centre, along with everything else.  Then space expanded.  Every single thing moved away from every other single thing at once.  In essence, the three dimensions were curled into a single dimensionless point, and then they unfurled.  Space came into being, without expanding into anything.  There wasn't any thing to expand into, because there wasn't any space...the three dimensions didn't exist, let alone space.

So everything is still at the centre, the centre's just got bigger.  You are, right now, sitting on top of the exact spot where the Big Bang happened.  So am I.  So are the biscuits in the cupboard, and the bit of the Moon they stuck the flag in, and Uranus, and stop giggling at the back.

The Big Bang happened everywhere.  The entire observable Universe, all of it, is still in exactly the same place it always was...here.  It expanded, yes, but it didn't expand into anything.  It's still just here, at the centre, where it always was.

Current physical theory does indeed suggest that the Earth is at the centre of the Universe...it just defines "centre" in a slightly more interesting and physically real way.  The Church, as quoted by GWR, are missing out on something huge, and that's a pity.  If there is a god, and a good scientist has to accept the concept if not the hypothesis, then he's made a very interesting Universe indeed, and choosing to ignore the whole glory of it all is blasphemy in itself.



As a serendipitous follow-up, my flatmate just told me about Guy Consolmagno, a Vatican astronomer who just happened to be on BBC4 last night (iPlayer - 21:15).  A man with some very interesting views, and proof that GWR are probably far from the only Catholic views on spacetime.

Tuesday, 31 August 2010

Review of Music Of The Primes

I've just finished a lovely, lovely book by Marcus du Sautoy on the history of the Reimann Hypothesis, one of the biggest problems in mathematics, ever...

..it's driven at least one person to madness, and taken a few to the borders.  It's the stuff that techno-thriller spy movies are made of (literally, see Sneakers) and has been implicated in at least one fatal duel and one national revolution.  It's been the subject of, and I kid you not, two Nobel Prize level practical jokes.
 Full review on my Cool Science Books blog...

Monday, 9 August 2010

P=NP? P!=NP? What The Hell Is That All About?


Firstly, an apology.  This is an attempt to explain, to the layman, something which I barely understand myself.  This might not work....apologies all round if it doesn't...

You may have heard that somebody recently submitted a proposed proof to the P=NP problem in maths.  The someone in question is  Vinay Deolalikar, a researcher at Hewlett Packard.  Whilst he developed the paper outside of company time he's still speaking within his field of expertise, this isn't just an obscure pure maths problem, it's one that has some very important consequences for virtually anyone who uses a computer these days.  That's you by the way, unless you're reading this on a printout, and kudos if you are.

The P=NP problem is, in plain English, about how long it takes to find the right answer when there's lots of answers.  It's all about a particular kind of problem, one that produces a lot of potential answers - the Travelling Salesman problem is a classic example.  Imagine you have to visit five different cities, you know the distances between each of them, and you want to visit every one of them, from any starting point, and travel the shortest distance possible.  

The obvious solution is to check every possible trip and find the shortest that way.  The number of possible trips is the number of cities (5) times the number of the next city you could visit, times the next....and so on.  "Five factorial" if you want the proper name for it, or "5!" in shorthand.  (This, annoyingly, has nothing to do with the "P!=NP" you may have seen, even though there's an exclamation mark involved.  There's only so many keys on a keyboard so while mathematicians use "!" to mean "factorial" programmers and computer scientists use "!=" to mean "does not equal", we'll come on to that bit later)

So we've got 120 different possible trips...just find the shortest of them, easy, you can probably do that without using your fingers, let alone a computer.

So what about six cities?  Turns out there are 720 trips to test.  OK, it's do-able in your head, but a computer might be helpful.

Seven cities: 5040 trips.
Eight: 40,320
Nine: 362,880

To find the shortest distance between fourteen cities you need to test 87,178,291,200 trips, which is getting a bit silly.  In fact, you very quickly get into the realms of needing a supercomputer, and beyond than even faster.  It's an "NP Complete" problem, and computers hate them.

The big question is, can you find the shortest route another way?  Plenty of people have tried...a particularly cool method is called "ant colony optimization", you write a computer program that simulates ants.  Yes, really, ants.  Each one wanders around between the cities (OK, ant hills) leaving a trail of scent behind it which slowly evaporates.  Whenever an ant reaches an ant hill it follows the path with the strongest scent.  Very quickly you end up with a strong scent trail on what is usually the shortest route.

And therein lies the rub.  Usually.  That doesn't count in maths.  However cool your insect based algorithm is, even if it works 99.999% of the time, it's not a proof.  You can never be sure it's the shortest route without testing it against every possible route, which brings us back to square one and the "computers hate NP Complete problems" thing.

What the P=NP problem really is is the simple question "Is it even possible to find a quicker solution than testing every trip?"

Actually, it's slightly more technical - it asks "If solutions can be checked quickly, can a particular solution be found quickly?".

In the case of the Travelling Salesman this makes a little less sense, but a better example is prime numbers.  Prime numbers can be checked to see if they're really prime quite quickly.  Take 6,538,732,799,420,108,322 for example.  That's a big number, but is it prime?  The answer, fairly obviously, is no.  It ends in a 2, so it's not prime.  That's an example of a really easy check that takes no time at all, we don't have to try dividing it by every possible number because there's a more obvious solution.

Now try finding the next prime number after 6,538,732,799,420,108,322 (without looking it up on the internet...)

Bit trickier huh?

That's a good example of the P=NP problem right there...is there, even in theory, a quicker solution than testing every number bigger than 6,538,732,799,420,108,322 until you find a prime one?  (And trust me, that'll take ages).

Pic courtesy of the wonderful xkcd, by kind permission.

The majority of mathematicians and computer scientists believe, in fact, that P!=NP, that there are some problems you just have to do the long way.  The longest possible way in fact.  And the suggested proof supports this.  If Vinay Deolalikar is correct then several things will happen:

  1. He'll win $1,000,000 for cracking one of the Millennium Problems, one of the great mathematical problems of the last few hundred years.  (Another fell in March this year with Grigori Perelman's proof of the Poincare Conjecture)
  2. He'll quite possibly win a Fields Medal, the maths equivalent of a Nobel Prize....but only if he's under 40 years old.  
  3. The world of cryptography will heave a sigh of relief.
  4. There's every likelyhood that the share prices of the major banking electronics companies will peak a little.
Cryptography and banking are the "real world" news here in many ways.  Whenever your bank details or credit card details are sent over the internet there's an NP Complete problem involved.  Your card details are jumbled up using very big prime numbers, and un-jumbling them is very, very nearly an NP Complete problem.  There is a shortcut, but it 100% relies on one little piece of information about how the jumbling was done.


To hack the transmission you either need a copy of the bank's bit of information (a stunningly well guarded and regularly changed bit of information too), or you need to spend several years or even decades with the most expensive computer on the planet running at full whack.  You can do it, but by the time you do the card will have expired.


You can crack bank codes, but it's not worth it.  The question has always hovered though...could some bedroom genius suddenly turn up out of the blue with a quick way to crack it?  If s/he did then secure internet banking as we know it would cease to exist...a replacement would probably be found quite quickly, but the same fear would exist, could the replacement also be cracked at any time?


If P!=NP as suggested then it means there will never be a quick way to break the banks codes.  As computers get faster the banks can simply use bigger and bigger prime numbers, of which there's an infinite number.


Until quantum computers come along at least, but that's a whole other story....

Saturday, 7 August 2010

Asus Eee 1001p Review. (Plus a bit of a hack)

So I've finally splashed out on a new computer.  To be honest it's not hugely different to my current machine, a 1.66MHz processor, 1Gb RAM, 140Gb HD, pretty standard gubbins all round in fact.  The big difference is I can lift this one without turning a funny shade of scarlet - it's a netbook, a tiny little Asus Eee 1001p.

Pic from Asus website
It's really pretty cool.  The version I got (from User2, my favourite indy computer shop) came with XP pre-installed, which saw the light of day for about half an hour while I downloaded and installed Ubuntu Netbook Remix.  I'm not normally a fan of "Fisher-Price" style GUIs, normally full of big friendly buttons and presumptions about the user, but UNR is cracking - a pretty much standard version of Ubuntu but nicely optimised for netbooks, especially the wide-but-short screen.  Every single aspect was intuitive and worked straight out of the box except for the wireless (you need to install the ndiswrapper and the original XP driver, there's a guide that shows you how to do it in about five minutes), and the multi-touch trackpad functions, although the side scrolling is fine out of the box, so I'm not especially bothered - Ubuntu hasn't yet caught up with the funkier aspects of touch interfaces yet, but it's only a matter of time.

So it's safe to say I like the OS, even if it's not the one that came with the machine.  Asus don't seem to be making quite such a song and dance about Linux as they did when the original Eee came out, but their website still clearly labels machines as supporting GNU/Linux and given the ease of installation I'm guessing they're still quietly keen on my favourite OS.  To top it all, whilst trying to get into the BIOS I made a little discovery that doesn't seem to be advertised...there's another OS which appears to live on the motherboard - a tiny little linux distro.  That's right, you can pick up all the Windows viruses you want, corrupt whatever you want, hell, you can even wipe the HD....and the machine will still boot to a useable OS with internet support and a frankly rather swish GUI.  In seconds too.  I'm surprised Asus don't make a little more noise about this, it's a wonderful feature.

Hardware wise, it's pretty much faultless considering it's a netbook.  It's respectably quick, you've got all the usual ports, 3x USB, external monitor, MMC-SD slot, ethernet and separate audio in/out sockets.  The HD is big enough for all but the most ardent movie fans and who really cares about optical drives anyway?  Battery life is good - I'm getting a "real" six hours, so Asus' claim of eleven isn't utterly outrageous if you're really careful, and there's a bigger, meaner battery pack available should you feel the need.  Hibernation, previously a problem for many linux distros, works flawlessly.  I've not managed to find out battery life whilst hibernating, but it's "ages" at least.  The matt carbon-fibre style finish is rather funky and prevents the usual smeary finger-prints if that bothers you.

So it's all pretty funky.  Downsides?  Well, the border between the trackpad and the casing isn't particularly tactile, it's easy for your finger to run off the edge leaving you trying to scroll with the case.  A tiny little raised plastic ridge around the trackpad would be a very nice addition to use-ability.  That's about it really...it's difficult to be much more critical without going down the "it's a netbook but I really wanted a laptop!" route.  It does what it says on the tin, and very smoothly indeed.

Which brings us to the bit where I start showing off.  Netbooks are, obviously, quite steal-able objects.  This one could even be hidden in a pocket if you have slightly bigger than average ones, so what to do?  Well, it's not a perfect solution but I rather like it:

Firstly, set up a guest account.  Don't give it a password, make it easy to get in to, it's a honey trap.  Turn off all the admin features etc, but make sure you can still connect to the internet via wireless.

Next, install (sudo apt-get install...) two little programs, fswebcam and googlecl.  The first is a very lightweight command line webcam program, the second is Google's rather natty command line interface.

You'll need a config file for fswebcam, I used this (securesnap.conf):

log /home/guest/.webcamlog.txt
#log /dev/null
device /dev/video0
skip 10
jpeg 80
#deinterlace
resolution 1600x1200
no-banner
set "Sharpness"=200
#set "White Balance Temperature, Auto"=False
set "White Balance Temperature, Auto"=True
set "Backlight Compensation"=0
set "Brightness"=130
set "Contrast"=32
#32 is default
set "Saturation"=28
#28 is default
frames 1
#frames 255
#loop 1


You'll also need the following script:

#!/bin/bash
while [ true ]
do fswebcam -c /home/guest/.security/securesnap.conf
google picasa post --title "Security Shots" /home/guest/.security/output.jpg
rm -f /home/guest/.security/*.jpg
sleep 30
done


Set the second script to run as a startup program when guest logs in, and voila, it takes a photo with the webcam every 30 seconds and uploads them to a picasa account (you need to give it your picasa user name the first time you run it, via terminal).  I can't get it to stop when guest logs out, but that's hardly a big issue.  I'll write an installer to automate it all when I've got time.

Monday, 2 August 2010

CME aimed at Earth

SpaceWeather.com is reporting that the Sun has got a little bit busier recently.  After months of suspiciously quiet behaviour we've had a "complex global eruption".  A sunspot has suddenly flared up, and a filament of material has erupted from the surface.  The two events occurred together, the suggestion being that they are both symptoms of a single event.  The flare and the filiament appear to be separated on the surface by about 45 degrees, meaning it's an event covering a substantial proportion of the Sun's surface.

To top it all the SOHO satellite has filmed a Coronal Mass Ejection (CME) aimed squarely at Earth.  A CME is basically a lump of Sun-stuff, a very thin, very hot plasma, being flung out from the Sun at very high speed indeed.  This one should reach us sometime on the evening of the 3rd of August.

Don't Panic.

This is a relatively small CME, and will probably just give those of us in the northern part of the globe some rather pretty aurora.  Maybe more, it's not inconceivable that there will be a little disruption in communications if satellites have to shut down to protect themselves, but please don't go believing any apocalyptic 2012 nonsense you hear.

Anyway, we've all got a Zombie Plan, haven't we? ;)

Thursday, 29 July 2010

Information Flood

I've just been thinking about the sheer volume of information I'm processing these days, and to be honest it's a bit freaky.  You can read about it all you want in cyberpunk novels (Charlie Stross's Accelerando is superb), but for no particularly good reason it's smacked me square in the eyes today.  I've got future shock.

When I was a kid, back in the eighties mostly, I read voraciously.  A book every few days, copies of Reader's Digest that were all sat in the living room ("I Am Geoff's Fight Club Reference").  My friends would phone up sometimes, but mostly we'd go out to play, two or three of us running around in a forest usually.  And there was the TV: three, later four channels.  I remember Doctor Who, Blakes 7, Blue Peter, Challenger and Ghostwatch rather vividly.

But these days it all a bit different.  I've got feeds at work from the book industry's main news sites, Slashdot and New Scientist because of their book reviews, my calendar, notes to myself plus the quantum physics/GR section of Arxiv for personal interest.  I've got a "home" version as well, with my personal email, Twitter feeds from the six most interesting people on the planet, IM client and the like.

I get about twenty or thirty phone calls a day, skim read about thirty books (you can usually tell if a book is "science" or not with a few random paragraphs), ten or so emails plus the usual social interaction thing....you know, humans.

It's an order of magnitude change from three TV channels and a few books a week, both in terms of volume and also of the sheer number of sources feeding into my own little head.  It's really quite startling, I feel a little like a rabbit facing a UFO...

Sunday, 18 July 2010

i-dosing, Night-Trips and Drug Induced Hysteria

Telegraph editor/blogger Tom Chivers recently posted an amusing (and slightly scary) piece about the latest drug craze sweeping the US, "i-dosing".  


i-dosing is a digital drug - you simply download it, plug into some headphones and get high.  That's the theory anyway, and at first glance the public and state reaction seems to be the usual hysterical, kneejerk "think of the children" approach so beloved of the conservative right.  


If you're thinking this all sounds a bit crazy then you're probably right, and I can't help but feel there's a rather subtle mass prank going on somewhere, akin to Brass Eye's marvellous episode about the dangers of Cake, "A totally made-up drug" which led to questions being asked in the British parliament about a fictional and clearly ludicrous "drug" and its non-existent dangers to society.


But enough politics for the moment - you are clearly itching to try this new internet based way of getting off your head.


What you'll need is a ping-pong ball, a sharp knife, headphones and a computer connected to the interweb - essential drug paraphernalia for any dedicated i-doser I think you'll find.  Firstly cut the ping-pong ball in half around its circumference.  Put them to one side, you'll need them later.  Next sit down with your favourite search engine and find a "binaural tone" as an mp3 file.  Different tones have different effects simulating various different drugs apparently.  Now lie down somewhere quiet, place the ping-pong balls over your eyes, stick the headphones on and hit play.


Pretty wacky, huh?


In essence what we're looking at isn't a drug, it's a high-tech meditation technique.  


You'll get effects that are just as wacky by staring a a candle while trying some breathing exercises.  Far from being a dangerous new drug, i-dosing is likely to be beneficial if anything.  The research is very inconclusive and generally badly controlled, but what there is suggests that meditation may be effective in reducing stress levels.  At worst, i-dosing does nothing.  At best, it's possibly a very useful practice for your average stressed out teenager.


If you want to get really hardcore, get into night-trips. I've been doing night-trips for over 30 years now, pretty much every day, and I can't see what harm it's done me. Obviously, like any drug, it's best saved for an evening when work is finished (doing night-trips at work is generally frowned upon!). Firstly, you feel a little drowsy and lethargic, then you pass out entirely, typically for eight hours or so. The unconscious stage of the night-trip is punctuated with exceptionally vivid hallucinations, often weird, frequently pleasant but sometimes utterly horrifying. One of the worst I ever had was a night-trip where I thought I'd killed my two best friends in cold blood.

The comedown from night-trips isn't too bad - you're usually a little disorientated when you regain consciousness but that soon wears off. Many people take a mild stimulant to get over it.  If the conservative right want to ban anything, it should be night-trips, not i-dosing.


Aside: According to I Write Like this article is written in the style of Cory Doctorow.  I'm happy with that :)

Tuesday, 13 July 2010

Fermilab May Have Found Higgs Boson

Tommaso Dorigo, a physicist working on projects at both CERN and Fermilab has posted a strong suggestion that the decades old Tevatron accelerator in the US has pipped the European LHC to the post when it comes to the Higgs boson. The signal shows a three-sigma effect according to at least one of his sources, meaning there's a 0.3% chance that it's an experimental error. If true, the readings would indicate a Higgs mass of around 115-140GeV, very much at the lighter end of the theoretical range.

It's all highly speculative at present, with Dorigo himself admitting: "keeping particle physics in the press with hints of possible discoveries that later die out is more important than speaking loud and clear once in ten years, when a groundbreaking discovery is actually really made, and keeping silent the rest of the time.