Sunday, 31 August 2014

peak sun

We don’t have all the data for August yet, and today is quite sunny, but it’s not going to change these figures much.

These two plots show our daily solar power generation in kWh, month by month.  The first plot shows the actual daily values (with some jitter applied to the horizontal position, to prevent points overlapping).  The second shows violin plots (box and whisker plots of median and quartile statistics, overlaying a kernel density plot, which is a smoothed version of the jitter plot).

So it looks like summer is over!

Notice that August has a low outlier, for a very dark and cloudy day.  That was Bank Holiday Monday, of course!  Other months have had days as bad as this, but they weren’t outliers; other days in that month were poor too, and the overall interquartile range is high.  August days are relatively clustered around mediocre (so a small interquartile range), making the Bank Holiday a significantly bad day!

Saturday, 30 August 2014

book review: Losing the Head of Philip K Dick

David Dufty.
Losing the Head of Philip K Dick.
(aka Lost in Transit, aka How to Build an Android)
Oneworld. 2011

In 2005, a disparate group of computer AI and robotics researchers got together, and decided to build an android recreation of the science fiction writer Philip K. Dick. They chose Dick because they had access to a huge archive of his writings and in-depth interviews, allowing them to build an Eliza-esque system that could converse in a Dick-like manner by drawing on this large database. The project went well, drawing in fascinated crowds, until the fateful day they lost the android’s head…

This is another of those “true-life fly-on-the-wall” tales of heroic scientific and engineering endeavour. It is an interesting, if somewhat pedestrian, recounting of a true story that could never be told as fiction, as it is too unlikely. Here the author is himself a researcher, rather than a journalist, so we get fewer of those irritating vignettes common to works that focus mainly on the people.

Yet there is a disappointing lack of technical detail. For example, we get a few transcripts of amazing conversations the android held with the public (although presumably heavily editied: there is a YouTube video of an actual “conversation” that is impressive, but less “intelligent”; there is also a website with some photos), but we get only a glimpse of what is going on inside the android’s “head” (the relevant computers are actually in a box to one side) at the time.

One interesting piece of technical discussion is about the so-called “uncanny valley” of near-lifelike, and hence creepy, robots. David Hanson, the developer of the life-like animated head, disliked the notion, so delved into the literature to find the evidence. Apparently, there was none: it was originally just an hypothesis, that then got taken up. Moral: always go back to the source material!

Moral 2: always make sure you have all your belongings with you when leaving the plane. The most I’ve left behind is a book. A head is a whole other problem.

For all my book reviews, see my main website.

Thursday, 28 August 2014

sequestering carbon, several books at a time XXIX

The latest batch:

This includes two copies of the Worldcon Souvenir Book, and some books recommended on BoingBoing (you’re not helping, guys!)

Wednesday, 27 August 2014

Bees and Bombs and Gifs

The Bees and Bombs tumblr shows great geometrical gifs.

(found via BoingBoing)

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Sunday, 24 August 2014


Tiny comet Churyumov–Gerasimenko, next to LA (well, if it were a bit stronger…)

Context is everything.

(via BoingBoing)

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Saturday, 23 August 2014

until we have faces

Why do demos like this always seem to zip over the interesting bits (the Total Recall-like bit near the middle!)

(via BoingBoing)

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Monday, 18 August 2014

Loncon 3 : Monday

For the sake of tradition, here is a photo from our hotel window, showing the ExCeL loading bays at the back, and the work on the new Crossrail in the front.

A Room With A View
After breakfast, we checked out of the hotel, leaving our luggage for later collection, and walked across to the ExCeL for the last day of the Worldcon.

First up was a talk by Dr Nicholas Jackson, on Knots in Non-Euclidean Space.  Nicholas has been giving interesting general talks on mathematics at Eastercons: this time it was based on some of his own work.  I got lost towards the end, but it was all done in his clear, amusing, and interesting style.

Next was a panel on The Politics of the Culture.  Banks was a fairly consistent Old Labour social democrat; reviewers seem to assume his characters’ opinions are his own, though.  Ken MacLeod told the story of The Use of Calculators as Iain’s proposed route to his Marxist communist utopia of “a stateless and classless society based on automation and abundance”. Many of the Culture novels are based on the Minds having a strong sense of the cost of backwardness, and a moral imperative to uplift, and then working through the complications and consequences with a degree of rigour.

At noon I went to see The Compleat Wrks of Wllm Shkspr (Abridged), by the RSC Shakespeare Company: 37 plays in 97 minutes, including all the comedies at once, and Hamlet several times, faster and faster, and then backwards.  I’d seen it many years ago; it was well worth seeing again.

Lunch, and then my final panel the con: The Scientific Culture.  Here no Banksian reference, just a discussion of the culture (with a small ‘c’) of science and scientists.

The end of a great Worldcon, my fourth: I went to Glasgow 2005, Glasgow 1995, and Brighton 1987.

And, coming full circle, I left the ExCel for Brighton, where tomorrow I give a tutorial on complexity and emergence at the Student Conference on Complexity Science.

And so to bed, in a different hotel, now by the seaside.

Sunday, 17 August 2014

Loncon 3 : Sunday

Sunday started out well with Dr Jenny Rohn’s great talk on antibiotic resistance in Revenge of the bugs: how bacteria have re-emerged as a serious threat to our existence.  Bacteria have been shaping our evolution by slaughtering the weak for as long as we can tell.  In the 20th century we began to fight back with antibiotics, but the bugs are out-evolving them, at an accelerating rate.  Not only that, but we’ve stopped making new antibiotics, because it’s just not financially viable: the low hanging fruit is gone, and the financial incentives are wrong.  It’s a health catastrophe on a par with climate change.  What to do?  Write to your MP demanding action!  And don’t take antibiotics for a cold.

Next was Authors Accept, Encourage, and Create Fan Works Too, a panel about fanfic.  All the panel indulged to some degree; some had learned their craft that way.  Despite some people looking down on fanfic, they pointed out that screenwriters, for example, are all playing in someone else’s sandbox.  If you do work for hire, there are restrictions: don’t kill off a major character, no explicit sex, no crossovers; so for a fan writer, why would you bother? Some authors send cease and desist letters under the mistaken impression they need to do so to protect their copyright (they don’t) or their trademark (they could authorise instead).

Next was a history panel, Seeing the Future, Knowing the Past.  Real history is messy, full of contingency, short bloodlines, and instability, so why does fantasy insist on prophesy and “rightful heirs”?  And all this “last in the long line of kings”, like Aragorn.  In reality, you are either everyone’s ancestor, or no-one’s; nearly everyone is a descendant of Genghis Khan, and he died only about 800 years ago.  However, it is a function of fiction to put order onto messiness and chaos; it provides a controlled environment where we can get answers (although this is a relatively recent trend in literature).  Also, fantasy likes grand overarching narratives.  In reality, prophesies do exist, but are often written in retrospect.  People blame Tolkien, but he didn’t do this kind of thing: he was a “messy” writer, with lots happening. Quote of the panel: “I don’t blame Tolkien; I blame Terry Brooks!”

The Secrecy in Science panel discussed to pros and cons of keeping experimental data secret until it has been fully analysed, and published by the scientists who have spent most of their career on the specific project.  NASA releases all its data immediately; ESA is more restrictive. There was also some discussion on the move to publishing the results of all drug trials, not just the successful ones, and the use of Open Access.

Lablit (laboratory literature) discussed a wide range of stories featuring scientists going about their research, as part of a contemporary story, not science fiction.

Botanical Conquistadors was an interesting panel.  The moderator asked the rest of the panel a sequence of questions designed to get them to incrementally design a terraforming strategy.  The structure worked really well, leading to musings on giant evolved tardigrades, planet-covering HeLa cells, and Japanese knotweed as a mulch.  We also learnt interesting facts about terraforming, such as the need for nitrogen, and how mosquitoes are a key species as food for birds.

We finished off the day attending the Hugo Ceremony.

And so to bed.

Saturday, 16 August 2014

Loncon 3 : Saturday

At breakfast today, we shared a table with a woman with limited mobility, who had hired a mobility scooter to traverse the ExCeL.  She amused us with descriptions of many different ways to incorporate such the scooter in a hall costume, Davros being merely the starting point.

My first panel was 1938: The Year In SF/F, discussing the retro-Hugos.  The world was different then: SF was mainly published in magazines in the US, and it was possible to read everything every month, twice!  The UK market was completely separate.  It was suggested that some of the retro awards were won because present day fans were voting for the author, not the work; one panelists suggested there should be a rediscovery award for unfairly neglected writes, and suggested Raymond Z Gallun as a nominee.  It was also noted that every book on the 1938 list was part of a series.

Next came Banksian, a  panel discussing what the term means, and who is writing it today. Ultraviolence as a feature was discussed, but it was pointed out that while Banks wrote violence, it was never the star; there was always a strong moral content, and the reader was supposed to be sickened by the violence.  Next on the list was the expansive, inventive scope and scale, of time, of events, of artefacts.  Before Banks, spaceships were 500 yards long, after, they were 500 miles.  Then the panel discussed his experimental, unusual writing techniques: the inverted story structure in Use of Weapons; the dialect in Feesum Endjinn; 2nd person narrative; epistolary structure of Excession.  Of course, anyone copying any of these styles wouldn’t be experimental!  Banksian politics is socialist utopian individualism, which needs the Minds to keep everything stable.

With a change of focus from science fiction to science, I next went to the Climate Change Narratives panel.  The discussion oscillated between how to write a compelling story about climate change, and how to redesign economics to properly account for climate change. Kim Stanley Robinson was in full flow about the way current economics says we can’t afford to save the planet (we can’t afford to leave all that valuable coal in the ground), and how that means we need a better economics: “current economics doesn’t make sense – it’s astrology in support of the rich”

Next off to a fantasy panel:  “Your ‘realistic’ fantasy is a washed out colourless emptiness compared to the Rabelaisian reality.” Discuss.  Some authors claim to write their medieval fantasies full of straight white men, because “that’s how it was back then”.  The panel of historians begged to differ (although Edward James pointed out that Rabelais wrote fantasy, not reality).  Despite this, Kari had a lovely rant about how one of the problems of being a Celticist is the Celtic fantasy novels like Marion Zimmer Bradley’s Mists of Avalon and Gael Baudino’s Gossamer Axe, promulgating the Californian neo-pagan Myth of the Celtic Woman: quote of the panel: “Celtic women were property, not radical lesbian separatists!”

I grabbed a mid-afternoon pasty before going along to the Science Fiction Encyclopedia Reunion, where we heard the fascinating story of the design and production of the Science Fiction Encyclopedia, from the first edition onwards.

Next was The Post Human Future, a talk delivered by Astronomer Royal Martin Rees.  The first part was based around his book Our Final Century (he said how the publisher cut his question mark, and the US title was Our Final Hour, maybe because they want instant gratification!), which is about all the things that could wipe us out.  He then talked about space flight, and how it would be better to commercialise it as a dangerous sport rather than as tourism, so that the inevitable accidents won’t be as traumatic.  He finished off talking about the period from when the Andormeda Galaxy crashes into ours in 4bn years, to the far future of the universe, and the multiverse.  His talk was peppered with wry jokes and science fiction references.  Quote of the talk: “I tell my students it’s better to read first rate science fiction rather than second rate science: it’s more stimulating, and no more likely to be wrong”.

We finished off the evening with the Masquerade, which demonstrated amazing creativity and attention to detail.

And so to bed.

Friday, 15 August 2014

Loncon 3 : Friday

Day 2 of the Worldcon started with breakfast in the hotel.  We were late enough down to have to move into the overflow space.  We were joined first by someone who worked in the hotel, curious about the convention.  Next we were joined by a couple from Canada.  In fact, they were from St John’s, Newfoundland, where I had spent 10 days only a couple of weeks earlier! One of them worked at Memorial University, and knew the person I was visiting there.  It just confirms my theory that there are only 400 people in the world, 200 who you know, and 200 who act as backdrop.

First off was a talk by Prof Ian Stewart on The Science of Discworld, partly about the content of the four books he wrote with Jack Cohen and Terry Pratchett, and partly about the history of their production.  The aim is to explain science, which isn’t a problem.  The problem is that the Discworld short story that  forms part of each book must make sense in its own right, yet have no impact on the overall Discworld canon.  He told the story of reading a biography of Darwin, with all the accidents that nearly stopped his voyage of discovery, and the coincidences that then put him back on track.  Ian explained to his co-authors: “It’s the Wizards at work!”  Jack asked him what he was on.  [But, as my breakfast conversation shows, coincidences like this happen all the time.]

Next was the panel on The Pleasures of a Good, Long Info-Dump.  Science fiction often uses the info-dump, or the “As you  know, Bob…” scene, to provide essential background information.  In mainstream literature, this is thought to be A Bad Thing.  Here Kim Stanley Robinson had a long, interesting rant on why he rejected the term “info-dump”, a pejorative term invented by the Turkey City Lexicon, and called it “a failed attempt to assert you know how fiction works”.  Older fiction, like Les Miserables or Moby Dick, revel in the “expository lump”, and so modernism invented rules as a reaction to that, requiring “show, don’t tell”.  But science fiction is different.  It should not feel it has to conform to these other rules, which can be turned into an ideological control, suppressing SF’s way of being subversive, by reducing its power to blow people’s minds.  Alternatives to a lecture include using snippets from fictional encyclopedias (we were told Matt Ruff’s Mirage takes this to another level, by including the edit wars in an on-line encyclopedia), or use of what Jo Walton calls incluing.  Quote of the panel (from Cory Doctorow, of course): “The best dumps come at the end of a lot of anticipation”.

Next I took a break, and went to the enormous hanger-like room housing the Art Show, the Dealers’ Room, and several related exhibitions.  Having them all in one place like this was great.

welcome from the Hawaiʻian Dalek (yes, the brown lumps are coconuts!)

At 1:30pm I went to Dr Tori Herridge’s talk on How to Make a Dwarf Mammoth.  Starting from fossil hunter Dorothea Bate’s 1904 adventure on Crete, we had a whirlwind and fascinating tour of the paleontology of mini mammoths in the Mediterranean, including how they have evolved and gone extinct multiple times, and in parallel on different islands.  I can now safely say I know at least an order of magnitude more about elephants than I did before.  The answer to the title: get  a mammoth (or two), get an island, and wait 50 thousand years.

The Interview with John Clute was very Clutean.  He talked about his early days, his first novel, being a critic, his use of Fantastika as a term for “the literature of the fantastic as a whole”, how Fantastika is essentially to be read literally not metaphorically, his novel Appleseed (written from a synopsis for a tie-in novel for Elite), and the Encyclopedia [of which more later].  Quote of the interview “To accept that to reveal a book is to spoil it privileges the reader’s first reading”.

In the Ian Stewart Interview, Nicholas Jackson interviewed Ian Stewart about his life in mathematics, his popular mathematical writings, his undergraduate rock band, and his work with Jack Cohen.  After Ian’s earlier descriptions of the coincidences in Darwin’s life, it was interesting to hear his own stories of how he got his university place at Cambridge without applying for it, and his first academic job at Warwick without applying for it.  Quote of the interview: “Agents alternate between saying ‘don’t write so many books!’ and ‘when’s the next book?’”

My final panel of the day was What's New in Maths, which included some discussion of the recent Fields Medal winners.  Quote of the panel, of the Clay Mathematics Institute Millennium Prize Problems: “There are easier ways to earn a million dollars”.

We rounded off the evening by going to the Worldcon Philharmonic Orchestra concert.

And so to bed.

Thursday, 14 August 2014

Loncon 3 : Thursday

We left home at 7:30 am to travel to Loncon 3, the 72nd World Science Fiction Convention, in London’s Docklands.  After a smooth mainline train, Tube, and Docklands Light Railway journey, we arrived at our hotel around 10 am.  It had rather confusingly changed its name from when we originally booked, but we found it, checked in, and dropped the luggage.  Then over the road into the ExCeL.  Which is HUGE.  We entered from the Custom House station end: registration was at the Prince Regent station end, so we walked the 500 or so yards through it.

There was a 45 minute queue for registration, which allowed chatting with other fans.  (This was the largest Worldcon ever, with over 7000 attending.)  Once we had our badges, we had the power to access the function rooms.  I had used the online guide previously to decide on which items to attend, so there was no need to frantically read the 240 page “pocket” programme guide.  There were up to 10 scheduled items happening at a time, so it paid to be prepared.

My first item was a panel called LOLcats in Space: Social Media, Humour, and SF Narratives.  The room was very full, and I ended up sitting on the floor at the back, and was too uncomfortable to take in much.  Full rooms were a recurring feature, but very soon signs went up: no standing, no sitting on the floors, due to fire safety regulations.  So several times I didn’t get to the event I’d planned.  However, I usually had a backup item available, given how much good stuff was programmed, or took the opportunity to grab something to eat!

Next I went to Loncon 3 Guests of Honour Discuss Iain Banks, where I did this time get a seat, as it was in one of the larger rooms.  Iain M. Banks was Loncon’s main Guest of Honour, but sadly died last year.  Here the other Guests of Honour remembered him, his work, and various previous con anecdotes.

3pm and it was time for Speculative Biology - An Introduction, part of the science programme.  This was partly about how life might be different, and partly about the history of people inventing different animals, ecosystems, and evolutionary histories.

What’s In a Name? was a panel about why writers use pseudonyms, and included Robin Hobb/Megan Lindholm, and Seanan McGuire/Mira Grant.  The reasons included: separating out different genres/sub-genres so that the public know what they are getting (particularly if writing both adult and YA books); changing persona to overcome previous poor sales; “diluting” an otherwise overwhelming presence if prolific; being a ghost writer, or house writer for a “brand” like Nancy Drew; hiding salacious content from your grandmother.  It was interesting to hear Robin Hobb describe how her name was carefully designed, to be gender neutral, to have resonances, to be short so it could be big on the cover, to begin with H to be at eye level in most book shops.  Quote of the panel: “Mira sells better than Seanan.  That really pisses me off.  I’m jealous of myself!”

The final panel of the day was Why Aliens Are Cool Again.  The panelists wondered if aliens had ever been uncool.  For example, the Doctor is an alien.  But Paul McAuley dismissed him as an example of “charismatic megafauna”.  And JarJar Binks was seriously uncool.

We finished the evening off with David Wake’s new play, The Cancellation and Re-imagining of Captain Tartan.  If you have seen previous incarnations of David Wake’s Captain Tartan series, you know what to expect.  Here Tartan is cancelled after a Blakes 7-style cliffhanger ending, only to be reimagined many years later as an American version, all in a dastardly attempt to remove the science from science fiction.  Side-splittingly hilarious.

And so to bed.

Wednesday, 13 August 2014

book review: Scala for the Impatient

Cay S. Horstmann.
Scala for the Impatient.
Addison-Wesley. 2012

Python is my current language of choice, but when you are writing something more substantial, having a strongly-typed language helps. One of my colleagues has been enthusing about Scala in general, and this book in particular, so I thought I’d give it a look.

Being not just the impatient of the title, but very impatient, I have frankly skim-read much of the book. Nevertheless, I’m impressed by what I’ve seem, both of the language, and its presentation here. Scala seems to be a well designed and interesting modern language, with many sophisticated and powerful features, but with no burdensome syntactic overheads.

The back-cover blurb offers a good summary of the key features described in the book. Scala compiles down to run on the JVM; it is object-oriented with functional capabilities; it allows mixin-style traits that can contain implementation code; it has support for parsing in general and XML in particular; it has extra support for concurrency through actors (thread-safe concurrent objects); and it has support for continuation programming (proceed with caution!)

The concise and focussed style of the book allows a brisk trot through many language features, whilst still containing a lot of technical meat, all introduced through code snippets. It does assume some knowledge of Java, as several of the examples contrast it with that earlier language.

A good technical read, making me want to try out the language, particularly the actors for complex systems simulations.

For all my book reviews, see my main website.

Tuesday, 12 August 2014

Fractal Experience

Eric Soderberg’s project.

(via BoingBoing)

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I snorfled at this tweet from Sean Carroll at a conference…

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Applications of Finsler Geometry to Speed Limits to Quantum Information Processing

New publication:

Benjamin Russell, Susan Stepney.
Applications of Finsler Geometry to Speed Limits to Quantum Information Processing
International Journal of Foundations of Computer Science, 25(4):489–505 2014
doi: 10.1142/S0129054114400073

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Monday, 11 August 2014

book review: Let’s Pretend This Never Happened

Jenny Lawson.
Let’s Pretend This Never Happened. 
Picador. 2012

If you already know Jenny Lawson as The Bloggess, then you will know what to expect (mostly). If you don’t, then go and subscribe to her blog immediately!

Terrifying, starling, disturbing, but mainly laugh-out-loud funny, this tells certain incidents in Lawson’s life that many might think implausible, but for which there is significant evidence (we’ve seen the photos of Beyoncé the giant metal chicken, after all). It’s all (mostly) in the same breezy style as her blog, even when the incidents are what most people would think as traumatic. We see more of Jenny’s childhood, and of Victor, than in the blog posts. There’s blood, and romance, and bobcats, and panic attacks, and zombies, and stuffed animals, all rolled into one.

Great stuff.

For all my book reviews, see my main website.

Sunday, 10 August 2014

sequestering carbon, several books at a time XXVIII

The latest batch, awaiting me as I returned from my North American odyssey:

Some were already in the delivery pipeline when I left.  Some were recommended during my visits, and then ordered, while I was away.  Some are proceedings from the conferences and workshops I was at.  And some are birthday presents, ready for my return.

I need to go and replenish the delivery pipeline now.

Saturday, 9 August 2014

Environment Orientation

Latest publication:

Tim Hoverd, Susan Stepney.
Environment Orientation: a structured simulation approach for agent-based complex systems
Natural Computing, 2014 (online)

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ALife publications

Presented at the ALife XIV conference in July:

Christopher Timperley, Susan Stepney.
Reflective Grammatical Evolution.
ALife XIV, New York, NY, USA, July 2014, pp.71–78. MIT Press, 2014.
open access

Adam Nellis, Susan Stepney.
Computational novelty: Phenomena, mechanisms, worlds.
ALife XIV, New York, NY, USA, July 2014, pp.506–513. MIT Press, 2014.
open access

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the failure mode of gel is "ick"

My two-month-old wrist rest ruptured:

Into the bin with it.

Friday, 8 August 2014

type the two words you see in the picture below

I was registering for on-line access to my water bill.  Part of the registration process has a Captcha.  I saw:

“Oh, that won’t work.”  I clicked the refresh button.

“Oh. So what are the chances of that?”  I clicked the refresh button.

“Oh.  There seems to be a pattern here.”  So I typed “200” into the text box.  And got through to the next screen.

Well, I suppose that “two hundred” is, after all, two words!

Thursday, 7 August 2014

compassion and Ebola

From the Washington Post article: I’m the head nurse at Emory. This is why we wanted to bring the Ebola patients to the U.S.

We can either let our actions be guided by misunderstandings, fear and self-interest, or we can lead by knowledge, science and compassion. We can fear, or we can care.

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Wednesday, 6 August 2014

how long is a piece of DNA?

Every cell in your body has 2 metres of DNA inside it. Yes, 2 metres.

This is easy to check.  Wikipedia says that one nucleotide [or base] is 0.33 nm long.  The same page also says that human have “3 billion base pairs of DNA arranged into 46 chromosomes”. However, other sites say that the 3 bn base pairs is the genomic contents of the 23 individual chromosomes.  (This demonstrates the value of checking several sites; I also checked the 0.33nm in other places.)  Since you have two copies of these chromosomes in most cells, that makes 6 bn base pairs all together.  And 0.33 nm × 6 bn = 2m.

That seems ridiculous: cells are too small to see with the naked eye, so how can there be a 2m long string of DNA inside?

Well, DNA is really really thin.  Wikipedia says the width of a DNA chain is 2.2–2.6 nm (and this number is confirmed elsewhere; you can check).  Assuming the chain is a cylinder, and taking a mid value of 2.4 nm, this gives a volume of 2m × π × (1.2 nm)2 = 9 × 10−18 m3, or (2 × 10−6 m)3, that is, a cube of side 2 microns.  That can fit in a cell, all folded up.

I’ve known this 2m fact for several years.  I’ve also known that there are over a trillion cells in the human body.  What I’d never done, until challenged by a colleague recently, was put these two together, to calculate the total length of DNA in the human body, with 2m in each of those trillion-plus cells.
Neptune: seems pretty close
in comparison
Actually, finding a value for the total number of cells is a little tricky.  I’ll go with 40 trillion.  So that makes 80 trillion metres of DNA.  That’s a huge number!  Astronomically huge. So let’s visualise it astronomically.

One astronomical unit, or AU, is the mean distance from the earth to the sun, about 150 million km, or 1.5 × 1011 m.  (I grew up knowing it as 93 million miles, but the world has changed units.)  That means you have over 500 AU of DNA in your body.  Neptune, the outermost planet, is 30 AU from the sun.  Your total DNA is nearly 10 times the diameter of the planetary solar system!

Another way to look at it.  Light travels at a speed of 3 × 108 ms−1.  Even at this colossal speed, it takes a while for light to get around the solar system: the moon is just over a light second away, and the sun is a full 8 light minutes away.  Dwarfing these, your total DNA is 3 light days long!

And yet that astronomically long piece of DNA length has a volume of 40 trillion × 9 × 10−18 m3, or 360 cm3, just about the volume of a soft drink can.  Really really really thin.

So, if anyone asks how much DNA there is in the human body, it’s 3 light days, or just over half a pint, depending how you want to measure it.

Monday, 4 August 2014

Enhance! Enhance!

Be afraid.  Be very afraid.

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