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Welcome to GlassHalfEmpty, my own little corner of the Wired. My name is Dan, otherwise known as Pewterfish in some circles, and I have collected a miscellany of occasionally interesting material in the following pages.
Go ahead, browse. You might find something worth your time.
This page is the Accumulator. Content on Glasshalfempty is organised into one of several categories, known as "stacks", and the Accumulator shows the most recent items posted to the site, regardless of stack. Public stacks are listed in the menu on the left-hand side: clicking them will restrict the view to that particular stack.
People are going to ask, so this is here, and public, so I can point people at it.
I left the Maelstrom game part way through the latest event (Appropriation, Easter weekend 2012), and I don't particularly expect to be coming back. I have absolutely no hard feelings for the team at Profound Decisions (who are the company running Maelstrom), and I expect to continue playing Odyssey and am looking at Empire with interest.
The Maelstrom game I played for three years was a game of exploration and intrigue, and I played a character with some pretty serious emotional baggage and a past he wanted to escape. He came to the New World, found people of like mind and founded a church. It was a good life for a bit. Then, the rumblings of apocalypse sounded under the surface. For the next couple of games things got bleaker and darker, and my character and a load of others fought against it, and it was good fun. The Undead rose, my God told me to fight them, and I did so to the best of my ability. Then, on friday, three quarters of the characters I play with were either killed or driven off the field for the weekend.
All of the above is fine. Interfactional tension is a fine thing, and it's been simmering along, grounding in little scuffles and scraps for years. We've all been expecting a fight like that, half the field against the other half, and now it's happened. And it's just driven home that the game as it is now isn't really the game I want to play.
Two data points:
Maelstrom continues to be a great game. It's a different game from the one I started playing in 2009, and the game as it stands is not one I wish to play. So I'm leaving, and reallocating my time to games I enjoy more. See y'all on the field in the future.
So, it's been a while.
Three whole months since a useful entry, in fact. So it goes. As you may have guessed, Advent Science totally imploded fairly early on when I realised I really needed to write the sessions in advance, not on the night. I have no doubt it's possible to put out that volume of information each night for 24 days and have it be correct, complete and coherent, but I wasn't able to do it. Maybe next year I'll actually do the prep :)
Work is work, and continues apace. My department has me doing a lot of XSLT and Python at the moment, and I'm finding that the latter isn't the terrible language I was sure it was a while ago. Syntactic whitespace still bugs me somewhat, but at least it isn't Perl... It's maintaining my interest without any trouble, and while it's a really big job, it breaks down into small achievable sections such that I get a sense of progress, which is nice.
At home, the house is pretty much sorted out now, though it could use a spring-clean. Everything works, there isn't too much mess around and I'm slowly getting used to the idea of having a living room for, you know, living in. I still spend most of my time in my bedroom, which seems like a waste of a space. Have to address that.
LARP is mostly going well (although see the following post). CUTT will start back up soon, I'm looking forward to the next Odyssey game, and I await more details on Empire with interest.
Anything else? Not much of significance. I have a new bicycle, which is nice for the commute (the gears and brakes work properly!). It's a Raleigh Oakland in British Racing Green, with aftermarket Schwalbe Marathon Plus tyres. The latter have taken my puncture rate down from two or three a month to zero in three months, and I highly recommend them for use on harsh commutes. My commute isn't too bad: cross the river by footbridge, cycle along beside the Cam for a bit, cross Newmarket Road and then follow Coldhams Lane to Cherry Hinton, then down the High Street and left at the crossroads. Thirty minutes / four miles each way, which has to be good for me, and it's all the nicer now it's still light when I get out of work in the evening.
February 1295
My name is Alexei Krybtanof. I am a child of Wallachia, and a brother of the Order of the Arcane Blade - a resident of a repressed country, and a tool of the repressors. And more.
Vivamortians took my country, my people, my family... I have been at war for as long as I can remember. A few days ago, my personal war took me to the cellar of a great house, a trap, the fight of my life and an escape. My friend Pavel spent his life to throw me clear across the Prime Material Plane, and I landed here, in Grantabrugge. I left too many things behind - my friends, my cause... and my wife.
Nothing else is worth a damn any more. I am surrounded by happy, free, innocent people, there is nobody and nothing of worth left to fight against or for, and my dear Alisa is lost to me. I'm dead in all but name, waiting for my body to fail or my spirit to depart, so that I can join my god and have done with this vale of tears. And hope against hope that I'll find Alisa there.
March 1295
"UNDEAD! HE'S UNDEAD!"
...the fuck?
I have my blade in hand and am casting about for a target when a coruscant marble of red-orange light arrows in from the floor of the bar and explodes an inch from my chest. I feel the last of the shield of magic unravel, steely silk against my skin. The next one will wound me, and I haven't the power to armour myself again tonight. I trace the path of the firedart back to its caster, a spell already forming on my lips and time ... slows ......... down.
A face I was sure I'd never see again. A body I know so well, armed and armoured, muddied and battered from the journey. Heels down from her feet to the ground and flame-red hair gathered and pinned up Just So. Buckles all the way down the front of her body, because lacing is too easily damaged... And her hand comes up, and traces a part circle, then pulls back, and another dart gathers out of the air into her palm, and I realise she's still trying to kill me.
The bar, at least, seems to recognise some remaining value in me: when they realise the slight woman in their midst is bent on beating my face in and setting the remains on fire, they pile on her in short order and bear her to the ground. And then... I have to explain to them why they should let her get up, and why I don't actually mind all that much that she's laying into me. And I would dearly love to, but something is blocking my throat, and leaking from my eyes.
And I remember the cellars of the manse of Petrovich, wadded cotton stacked against the footing-beams of every major wall, all soaked in paraffin. Alisa fairly capering between them, touching each one off in turn with the tips of her fingers, a smile on her lips and in her eyes. She catches me watching and traces a simple AA on the dirt floor with her toe, then darts across to the outside door (locks already broken, of course) and leads me out on to the moonlit moors as the fires start to rise. The sound of the party in the manse slowly gives way to screaming as the fire licks its way up and the house begins to come down, all the doors and windows strangely bolted and nailed shut...
And I remember the night we first met. Chasing an arsonist through the city, dodging around a corner into a crowded marketplace, following a pointed finger to see a cloaked figure fleeing, too far away and taking just too long to realise that they couldn't possibly have crossed the crowd in that time, and that a cloak lay piled at the feet of the woman pointing. Looking back toward her to see nothing but footprints. Later that night, off-duty, catching a face across a crowded bar, a spark of recognition and a spur of the moment decision to see where the night took me. Took us both.
And I remember our last moments together. Another cellar, more stacks of cotton, but no fire yet. Shouting. Some of our friends missing, one who has betrayed us. All the doors blocked off, save the one that shakes in its frame, splintering with each strike as the house guards force their way in. Trapped like mice in a cage, we circle the cellar, flinching with each *crunch* of shoulder on wood, trying to think of a way out. Pavel trips over a piece of exposed ironwork, catches the candle atop the stick in an effort not to fall, and feels the pulse of a ley nexus. We strip the drapes aside enough to find it, surrounded by candles and brown-stained urns and silver knives. Who knows what they did here. Right now, who cares? Pavel knows just enough to maybe have a chance of getting us out of here, and I help him start up the ritual, as Alisa watches the door. Minutes later we're exhausted, but ready, the nexus holds the matrix of a planar gateway that will get us out of the cellar, anywhere but here. I draw breath to call Alisa over, but at that moment the door finally parts, armoured guards begin to force their way into the cellar, and Pavel closes his eyes and pushes. Alisa looks my way, eyes wide, as I feel myself dissolve and begin to travel to somewhere ... else. She's far too far away for the ritual to carry her too, and for all that I can't look anywhere but in her eyes, the glint of metal in the hands of the guards fills my awareness...
...and she's gone. And blackness. And silence. And then lightnoisepainpainpain, and the floor of the Wessex Arms, all those weeks ago, and the faint echo of a scream in my mind.
And I find my voice, wavering and broken though it is "No, no... it is alright. Let her up, let her up. You see, she is my wife..."
We fight, we argue, we shout at each other and try to pile the blame and the worry and the tears and the sleepless nights on each others' shoulders. For the most part, the regulars in the bar are smart enough to stay out of our way. In time, we've said all we care to, and I stumble my way through my hundredth heartfelt apology, and she leaps into my arms with enough force to drive the wind from me.
Nothing else matters. I am surrounded by innocent, free people who know not the dangers we protect them from, and the people we protect from them. There is everything to fight for, and Alisa is by my side again. I have everything to live for, and I find I have a lot to do, because until my body fails or my spirit departs, I mean to fight for freedom and the safety of the world, and some day to go home and liberate my people.
And Azrael can wait.
For a time.
*tap, tap, tap, tap*
Flowing black canvas and glistening boots click down the stone corridor, purpose evident in their speed and precision.
...and twist and flick, and there's a scream, a crunch of bone and a spray of blood...
*tap, tap, tap, tap*
The torches, sconced high on the wall in serried ranks, glitter from tiny mirrors in the scarf around his waist, flare and sparkle from the caged garnet at his neck.
...riding high at her side, listening to them talk, wondering if they'll ever stop talking. What could two nations have to say to each other that was so important anyway...
*tap, tap, tap.*
A pause. A slightly twisted hand reaches out, grasps the doorhandle, turns and pushes it open. The plaque flashes in the dim fluttering light.
*ker-clunk, creaaaaaaaaaaak...*
...bound. Gagged. Forever silent, forever still. None will take me. None can handle me. None will show me light, give me life...
"I need a weapon."
The aged warlock behind the barred counter squints up at the man in front of him. Tallish, sturdy, with a sardonic cast to his features and a little pointy beard. Twinkle in his eye, focus at his neck.
"I see, my friend. None have ever made it this far within the walls without belonging here, but... I would be remiss..."
He passes the visitor a knife, and watches him sigh, close his eyes, pinch his finger and thumb and draw them down the blade. Watches with other senses as the magicks fuse, swirl and mingle in his hands, forming a pure grey and then twisting into something ... else before flowing into the knife. He inspects the result.
"Creditable. To whom am I to give one of my charges?"
"My name is Alexei Krybtanof..."
"...of?"
"...of the Chapterhouse in Nordvald, Wallachia. Of the Order of the Arcane Blade, whatever you disguise yourselves as here. I am tired, and far from home. And I, need, a, Weapon."
The guardian tuts and mutters to himself for a few moments, turning and inspecting the racks behind and beside him. At least thirty swords, axes, hammers and maces are racked behind the counter, with polearms and longer weapons hooked up upon the wall. All have the slightly oily sheen of warmetal, and all are unique - master-crafted weapons, not some crude design turned out by the hundred for a militia or a guard. He lays a hand on an axe, then draws its neighbour, a fine curved sword, and turns back to Alexei.
"This is Fang, last wielded in defence of the city by Journeyman Alastair Stern, during the Uruk attack on the city five years ago. He fell in battle, sadly, doing as he should, and Fang has languished here ever since."
"No."
"I thought not. Perhaps a mace, then? Does your taste lean toward taking people in, rather than taking them down? Thieftaker here is looking for a new holder since Maximilian retired at the end of January..."
"You name all of them!?"
"Well, they are all of them unique. Most of them come with names. When you're in a tight spot, it's easier to call on them by name, when you need to remind them to..."
"Yes, yes... Who is that, then?"
Alexei points, a spark leaping at his finger from the ward on the bars when he gets too close. The guardian follows his eyes, to the four-foot length of a greatsword, hooked high on the wall, point-down, and chained in place.
"...ah, that. I had expected it to be someone... younger. Although, I suppose you have the build. That, my friend, is Sylphia. She is an old blade, experienced, but wily. She has been upon my wall since before I came to this position. She is too much for most of us - she likes blood, and to clash with steel. You think yourself worthy? Able?"
"Take her down."
...warmth on my skin, light on my body and a sense of exhilaration, anticipation as I move through the air...
Alexei reaches out for the hilt as it passes over the counter, and feels a slight shock as his hands close about it. In years to come, he'll blame the counter-ward, shorting through the blade, but he's never quite sure.
"She's ... mine. I think."
He's mine.
The formalities are short, but necessary. Ten minutes later, the door closes behind Alexei and Sylphia as they walk, haft in hand, back out into the world.
The guardian watches them go, musing quietly to himself. The queen bitch has left her throne, it seems, and all the other blades in the room seem to sigh with relief. Hopefully this time she and her bearer will do good.
Hello again. In the last session, I talked a bit about electrons and charge, and tried to hook them up to concepts you're probably familiar with, like voltage and current. Now, I'm going to talk about conduction, and resistance, and semiconduction (this last being pretty vital for transistors, and the integrated circuits that are made out of them). I'm going to skim over them to some extent, because of all the material in this "course", the physics of conduction is the area in which I have least knowledge.
An atom, as I said in the last advent science session, can be considered as a nucleus (containing protons and neutrons) and a series of orbiting electrons. But those electrons don't all orbit at the same "altitude". It turns out that there are set "altitudes" (energy levels) at which electrons can orbit around the nucleus, and a certain number of electrons can fit in each. The energy levels aren't called energy levels for nothing, as an electron can move between them by gaining or losing energy - the more energy an electron has, the higher altitude it orbits around the nucleus, the higher its energy level. The terminology all kind of makes sense (although this is a massive simplification on the actual physics).
Different elements have different energy levels, and the spacing between the levels varies. The energy levels tend to be occupied from the nucleus out, as with time electrons will lose energy and fall inward to the lowest unoccupied level. An electron that has enough energy to transition to a higher level is said to be "excited". The highest energy level in which unexcited electrons are normally found for a particular element is called the Valence Band. The energy level immediately above it (which is "normally" empty of electrons) is called the Conduction Band. Electrons in this level can be exchanged between atoms moderately freely, as they are highly energised and loosely bound to their nucleus, but because electrons are drawn to positive ions (such as those created when an electron leaves an atom), it tends to be more a case of atoms swapping electrons with their neighbours than of electrons migrating freely around the material. As a rule, electrons in the Valence Band are too strongly fixed in place to move around like this.
As I said a while back, an electron must take in energy (and become excited) in order to step up to a higher energy level. This is ... mostly true. The trouble is, an energy level isn't just a single, clearly defined circle around a nucleus, it's a fuzzy band within which electrons can have one of several excitation levels, all very close together. So the bands can be different widths, and different elements have different distances between their bands... can you see where this is going?
CONDUCTORS are materials, such as metals, in which the valence band and the conduction band actually partially overlap. Electrons can swap in and out between the two bands freely. As a result, the conductor can be considered as a virtual sea of electrons, coexisting with a virtual sea of positive ions, despite the fact that the material as a whole is approximately neutral. Electrons within the conductor have a drift velocity (on the order of millimetres per second), which is the speed at which they move about, trading between atoms. Note, however, that electricity moves much more quickly than this (about 0.75 light-speed in vacuum). This is because electrons are traded, not moved - the whole thing behaves a bit like a Newton's Cradle. Push an electron in one end, and all the electrons jump forward one place in line, and an electron comes out the other end almost immediately. It's not the same electron, but it may as well be.
INSULATORS are materials, such as glass or rubber, in which the valence band and the conduction band are widely separated. Electrons need to gain a great deal of energy to move between bands, and they rarely manage it. As a result, attempting to push electrons in one end of a insulative material (or pull them out) has minimal effects, BUT it can cause charge buildup at the end. This is why insulative materials can hold a static charge - electrons are added to or removed from the material, but because it isn't conductive they can't go anywhere. The "not-electrons" that are left behind when electrons are removed are called Holes. They'll be useful later.
Finally, SEMICONDUCTORS are materials (like silicon) in which the valence band and the conduction band are close together. Electrons don't need a lot of energy to hop the gap, but they can't do it spontaneously. Semiconductors, it turns out, are really useful if you're smart in how you prepare them and lay them out - all integrated circuits are made from semiconductors. If a semiconductor is "doped" with other materials, it can be made to have a slight excess of electrons or holes, and when the two types of semiconductor are laid out in certain patterns, you can use a flow of electrons in one area to control the flow of electrons in a nearby area very precisely. But that's transistors, which is another session, yet to come.
I can't promise to post every day, as you've noticed, but I'm trying. The next session is on other fun particle physics trickery that's used in the field of electronics, then we'll move on to the actual machinery involved, starting with the transistor and moving on from there.
Hello, and welcome to Advent Science 2011, the pewterfish edition. This is a little experiment being performed by myself, pufferfish and duckbunny: we rather suspect we can teach our readership something interesting in the month of December, and we've each chosen a subject we know fairly well. It's kind of like an advent calendar, but each door conceals awesome knowledge instead of chocolate or paintings or Lego. Not that such things are bad, of course.
Pufferfish is talking about genetics, and duckbunny about the history of the atmosphere. In the next 24 days, I hope to lead you on a journey from science to engineering, and beyond, in one very narrow field.
Computers are everywhere these days, on our desks, in our pockets, in the back rooms behind companies like Google, and Facebook, and Oracle. They cook our food, wash our clothes, and guide our aircraft. But to many people, the computer is a magic box, a Thing within which humankind is not meant to peer.
That's nonsense. They're machines, just like everything else, the parts are just smaller and less obvious in function. I happen to know my way around them quite well, so I'm going to impart some of that knowledge to you, if you keep reading. I'll necessarily have to gloss over details from time to time, but I mean to touch everything important, and leave a trail of links for you to follow if you want to learn more.
Join me, then, as we wander from Electrons, to Email.
If we're going to go from Electrons to Email, I guess we'd better start at the beginning. Time for some particle physics.
The electron is a particle with a unit negative charge. That is, it is a particle with the smallest negative electrical charge known to exist - there's no such thing as "half an electron's worth of charge". An atom consists of protons and neutrons in the nucleus, and orbiting electrons: a proton has a unit positive charge, an uncharged atom has an equal number of protons in the nucleus as it has electrons orbiting it.
Opposites attract, as well we all know, and electrons are no different. Electrons, being negative, are drawn towards positively charged objects. But what's charge? It's the presence or absence of "the right number" of electrons. When I said that an uncharged atom has an equal number of electrons and protons a paragraph ago, I didn't mention what happened if the numbers weren't equal. If an atom has less electrons than protons, it is positively charged. If it has more, it is negatively charged. A charged atom is called an ion. Positive ions "want to" gain electrons, and achieve neutrality. Negative ions "want to" lose electrons. I put "want to" in quotes because there is, of course, no desire involved. Equally, it's not something I can easily explain without going deeper into partical physics than I really want to, so you kind of have to accept it.
Electrons are drawn to positively charged objects, and repelled by negatively charged objects. This is as true at the macroscopic level as it is at the atomic: a positive electrode will attract electrons, and negatively charged objects, to itself.
It follows that given a difference in charge, electrons will tend to flow from a negatively-charged object to a positively charged object, until the charges are equalised. This flow is called electricity. The chemical reactions within an AA battery cause one end to become more positive and the other more negative as they proceed, and it is possible to extract energy to light lamps, sound buzzers and so on by placing the item to be powered between the positive and negative ends: the electrons flow and, on their way, they power the item. Given enough time, the chemical reactions within the battery will cease as their fuel is consumed and the electrons will slowly drift back to equal out across the battery - this is what happens when a battery is discharged, or "flat".
The difference in charge between two objects is called the Voltage, or potential difference, that exists between them. The number of electrons per unit of time that flow between them is called the Current. Current is measured in Amperes, or "amps", and a single ampere is 6.241x10^18 electrons per second.
Given that that's an awful lot of electrons (roughly six quintillion), it should come as no surprise that in electronics, it is normal to deal with thousandths or millionths of an amp, or even smaller amounts.
So, that's the electron, more or less. I've glossed over some bits, because down at the tiny tiny scale of particle physics, it can be a bit too easy to get sucked down the rabbithole of detail, but that's enough that I can explain the next bit with. See you tomorrow.
For more in-depth information...
Well.
Well well well.
I live in Cambridge. And I work at (but not yet for) ARM. Life is more or less good. And I'm back on the net, as this entry shows. Hello again.
I have a (rented) house, which is still a mess, because I haven't finished unpacking (it's traditional, you know).
I have a job, and I'm responsible for a manual the company will be releasing soon. This is ... well, not going perfectly smoothly, but so it goes. I'm doing the best I can under tricky conditions, and I don't think it'll be too late (but when one's co-author, manager and mentor all independently go on holiday at the same time, there's only so much a new hire can manage).
Life is, for the most part, good.
Watch this space, I guess :)
So, I've been moved in for a bit over a week now, in theory, and I've unpacked .. some things. By the gods, do I have a lot of stuff. I've gone from a room and a half to a house and I'm still having trouble finding spaces in which to put everything. But, so it goes. If I unpack a box every so often, it'll get sorted out eventually.
I'm due to start work on Monday, and all the details for that are sorted out now. I still need to finish servicing my bicycle for the commute, but that's a couple of hours' work, and will probably be done on Saturday morning. Then I just have to find the route...
Not a lot to say here, really, but thought I should just put up a "things still happening" post. Money is tight, as expected after just moving house, but all the major bills are taken care of and I'm (barely) solvent this month. Once I'm actually being paid again, and Brighton Uni get that last pay-cheque to me, everything should be just fine.
For now, well, I guess it's cheese sandwiches for me :)
Having the river and Stourbridge Common thirty seconds' walk from my door is a lovely thing, though. I'll try and get some pictures at some point, and post them here. Realisation of the day, though: rowing skiffs have head- and tail-lights, and they appear to be exactly the same models as used on bicycles - horizontal lines of LEDs, powered by two AAA batteries per unit. It's odd, and interesting, to see the same design reused in a way I'd never have expected.
Well, as of this morning I have a house in Cambridge. We signed the contracts (which are ...detailed, but not particularly onerous), got the keys and set up the standing order to pay the rent, and now the house is pretty much ours. It's furnished, with a lot of things the landlady has provided, and we popped out and bought most of the missing bits today. Unaccountably, this does not include a vegetable peeler, because apparently nowhere in Cambridge sells ones I like.
There are a few issues I need to raise with the letting agency, mostly relating to the security of one of the external doors and the fact that the doorbell does not work, but for the most part I'm pretty happy with it. Once I've raised my list of issues, I wonder who the letting agency will think is more anal, me or the landlady... Given the place has fire safety posters, smoke alarms and fire extinguishers everywhere, she probably still wins.
Ah well. That's sorted, and I have a work contract in my bag to read and sign tomorrow. Things are coming together. Tomorrow I go back to Brighton, and finish putting things in boxes, then start moving in earnest. For now I have a new bed, and some Egyptian Cotton sheets. Tomorrow can wait :)