Thursday, October 23, 2014

[etotasem] Content hash to key-value

Given a database by which content can be retrieved only by the hash of the content, is it possible to build on top of it a key-value map with user-choosable keys?  If not, what more could be added to make it possible?

Want a distributed hash table.

Wednesday, October 22, 2014

[inkhrprb] Defining the start of the endgame

Let Queen count as 2 points and rook as 1.  The chess endgame has begun when both players have 2 or fewer points.

This does mean that a queen trade in the opening has gone directly to the endgame, for example the "Berlin endgame" of Ruy Lopez.  Castling and king safety is less of a priority; the king has become an attacking piece. This also means KQR versus anything is not yet an endgame, which probably goes against conventional notions.

Inspiration was an idea: adjournment becomes available when the endgame begins, and players can carefully study the position, improving the quality of endgame play.  Less radically, a new time control at the start of endgame.

Maybe both bishops together count as 1 point.

Tuesday, October 21, 2014

[awpnmpol] Salsa20 dance

The Salsa20 round function would be fairly easy to vaguely depict by a troupe using interpretive dance, not too surprising given its name.  Use some theatre special effect to accomplish a cyclic shift, most simply two dancers in identical costumes, one exiting one side when the other enters from the other side.  More elaborately, fly them up and over to the other side.

[qnckwtyz] Terrorism and free speech

Hypothesize that most terrorism is a symptom of a failure of political discourse: the terrorist feels mechanisms by which the best idea would win have become subverted.

This is more optimistic than the traditional military view which assumes no positive sum solutions exist.

Inspired by the school shooting threat of GamerGate.  There obviously exist many failures of discourse with both sides not even wanting to understand each other, and a positive sum solution fairly obviously exists: let market forces decide what games get produced, i.e., buy what you want to play.

[riirjmxe] How could so many smart people be so wrong?

Look for social forces which incentivize one answer over another.

Cargo cult science.

Enumerate those forces.  Seek to eliminate, or counterbalance, them.

[bzgrgdph] Cubes kissing spheres

How many identical cubes can be packed around a sphere of a given size, with each cube tangent to the sphere at the center of its face?

Inspired by setting Minecraft on a large spherical world.  There will probably be a few special regions in the world where cubes will be very distorted.  Depict "cubes" as Voronoi cells around their center point.


[vvgaczoc] 5GB Scrypt

Scrypt at suggested parameters "for a sensitive file" (N, r, p) = (2^20, 8, 1) consumes 1 GiB of memory, and memory use can be increased linearly by increasing N or r.

Does anything abruptly interesting happen when the memory requirement exceeds 4 GiB, the maximum for 32-bit addressing?  The first thought is this: For normal users on general purpose computers, all 64-bit machines, they won't notice any abrupt change.  However, for ASIC and other specialized crackers, a fully 32-bit infrastructure will no longer be sufficient: they will have to move to 64-bit memory addressing, doubling the cost of at least one (possibly small) part of their hardware.

On the other hand, so long as one is designing ASIC, using 33-bit addressing might not be that hard (not cost especially much more area than 32-bit), and in fact, 33 bits gives more advantage to ASIC over CPUs who are forced to process 33-bit numbers as 64 bits.

But perhaps better is automatically scaled difficulty as in Vertcoin.

Saturday, October 18, 2014

[walwathi] Unreliable interstellar engines

At low speeds of interstellar travel, starships need to function reliably for extremely long periods of time.

However, at high speeds, relativistic time dilation decreases the perceived time on board, so ship systems don't need to function that long.

Assuming a ship accelerates at 1g (measured in the ship's frame) for half the voyage and decelerates for the other half, what is the distance (measured in the origin's frame) it can travel as a function of time measured on the ship? I suspect exponential or super-exponential.

[ztzzsyqw] People are attracted to power

Another aspect of the seeming abuse of power to acquire sex is that people are often attracted to people with power, so making it difficult to always characterize it as abuse, so more difficult to regulate.

[pnxrzbdy] Prime zebra

Mark the primes as points on the number line.  Alternately color the segments between them black and white.  Scale the number line so that primes occur on average at the same distance, according to the prime number theorem.  The scale factor continuously changes.

Mark the Gaussian primes as points on the complex plane.  Form the Voronoi diagram separating them.  Color the regions in a few colors as needed.  Or Eisenstein primes.

[btznewuy] Transparency and social class

Transparency about power, e.g., government power, is a socially equalizing force.  Everyone gets access to information that formerly only the well connected had access to.

Hypothesize that the underlying reason behind the many instances of lack of transparency in the world are to maintain social iniquities.

[nuivefzr] What is real?

How can you tell if you are living in reality or living in an artificial simulation, like The Matrix?

Fall in love.  Have sex.  Do they seem real to you?  These are the experiences that evolution has given us extremely fine sensitivity to gauge.  We'll instinctively detect if something is even a little bit wrong about them; consequently they will be the most difficult things for a simulator to get right.

Cynically, if these experiences seem real enough, who cares if it is a simulation?

[wkedncfb] Pedagogical programming languages

The best beginner programming language would probably be the one with the best error messages because beginners will make lots of errors.  Extremely simple syntax.  Or perhaps many strings are valid programs. GOTO and IF as the only control constructs.  Arbitrary precision integer as the only variable type.

Is this subset of programming constructs interesting enough to keep a beginner programmer interested?  It probably depends on the standard library available. LOGO.

After that, what is the best "intermediate" programming language?

We could imagine a language with series of pragmas which enable higher-level constructs that the beginner turns on as he or she gets more advanced, perhaps through guided learning: StructuredControlFlow (e.g., "for" loops), Subroutines, Recursion, StructuredTypes, Arrays, HigherLevelFunctions, etc.  The error messages become more varied as the features interact.  Error messages should explicitly state which language feature it is about.  The programmer, if not expecting an error about that feature, can try turning the feature off to see what happens.

How can we encourage beginners to learn the more advanced features when (say) spaghetti code of GOTOs "works"?  There's an alternate school of CS pedagogy which attempts to teach structured programming from the start.  But this has a more steep, more difficult initial learning curve.

Should the end of the path, with all the features turned on, be a real programming language?  If not, how can we force it to remain pedagogical and prevent people from writing production code in a language not designed for production?  Pascal had this problem.

(What is meant by a language for production rather than pedagogical use?  Perhaps features like deliberate awkwardness to be able to compile to efficient code on modern architectures, syntax for writing useful libraries, linking with code written in other languages, concise syntax, features for software engineering: collaboration, playing nicely with version control, IDEs.)

Rather than pragmas, could a programming language have the ability to toggle its own features expressed in the language itself?  Probably Lisp.

Friday, October 17, 2014

[xftwgpnv] RGGB

Given that the human eye is way more sensitive to the green part of the spectrum compared to red and blue, it seems it would make sense for RGB displays to support more shades of green than the other phosphors (or LEDs, etc).

What is the optimal distribution of bits to describe a color within a given bit width?  (Assuming, or not, gamma correction has already been done.)  Perhaps 32 bits: 16 bits for green.

Wednesday, October 15, 2014

[atpznphw] Computers being clever

Under what conditions does the user appreciate the computer being clever?  Under what conditions does it add too much complexity so that user can't understand what is going on, perhaps to debug or modify the computer's behavior?

Inspired by autocorrection.

Monday, October 13, 2014

[ehzpngxv] Football without passes

What would football be like if the forward pass were eliminated?  Should the number of downs be increased, or the normal distance to first down, or length of field, be decreased?

The goal is to make the game less dominated by a few superstar quarterbacks who can throw forward passes well.

Baseball without the home run.

[summvoel] Size changing

Create a virtual 3D world, perhaps a game, in which you can change your zoom level by many more orders of magnitude than the real world (which is approximately 10^40).

We'll probably need procedurally generated detail, probably fractals.

Perhaps in the style of Minecraft.

[qwibqklp] Tessellating space with 2x3 Lego bricks

Place 6 2x3 Lego bricks next to each other so they form a 6x6 square.  Place squares next to each other alternating orientations in a checkerboard pattern.  The next layer of squares goes on top, with the center of each square going above the corners of the layer below.

The third layer faces a decision: whether the orientation of the 2x3 bricks in a square should be the same as, or perpendicular to, the orientation of the square two layers below.

I think this decision is isomorphic to the face centered cubic versus hexagonal close packing of spheres.

Practically this decision causes the difficulty of consistently creating this tessellation when a layer must be consistent with a now-covered layer two layers below.  There also exist some deep seams and weakly connected sections.

I don't think there's a decision to be made about the second layer; either decision results in the same tessellation, perhaps rotated.

Thursday, October 09, 2014

[opftlezw] Bughouse hourglass

Given bughouse chess does not progress to an endgame like orthodox chess, it is perhaps better played with a chess clock in the style of an hourglass (but digital, and precise) which does not impose a time limit to the game, but only to the difference in total time taken between the sides.

Same could be argued for shogi, but it is not done.

[ncamdwvm] Emergency shutoff of the third rail

A person falls or is pushed into the tracks off the platform at a subway station.  Although the oncoming train cannot be stopped on short notice, the electrified third rail could be, perhaps by an easily publicly accessible fire-alarm-like switch.  Turning off the rail gives the fallen person more options to reach safety.