“When You Finish A Direct Proof, You’ll Write QED. When You Finish A Proof By Contraposition, You’ll

I know we can’t build anything just by sitting in the dark together, but I am so fond of you it sounds like something a person would lie about.

Anna Meister, “Not Yr Cornfield,” published in Moonsick Magazine (via bostonpoetryslam)

A group of researchers have trained pigeons to identify malignant breast tissue in exchange for pigeon pellets. Here’s the real, not made up study.

This doesn’t mean hospitals will start employing pigeons. But it does suggest that studying pigeons could help us teach doctors how to process medical images. From the study:

Pigeons (Columba livia)—which share many visual system properties with humans—can serve as promising surrogate observers of medical images, a capability not previously documented. 

… The birds’ successes and difficulties suggest that pigeons are well-suited to help us better understand human medical image perception, and may also prove useful in performance assessment and development of medical imaging hardware, image processing, and image analysis tools.

Image credit: Levenson et. al.

Class in session as Planet X starts it off with our favorite dense objects: 

Neutron Stars!

http://www.space.com/22180-neutron-stars.html

failed my lab; got 150% yield on a reaction and apparently writing “god works in mysterious ways” as the conclusion to my lab report doesn’t fly in a university setting

Joseph Edmonson, Mechanical calculator, 1889. Brass and steel mechanism. Patented in 1883, Made by W.F. Stanley, England. Exhibit interface, Powerhouse Museum, Sydney.

Mechanical calculators were first developed to reduce errors made by human calculators. This machine was used for addition and subtraction and a complex instrument to master. 

in your opinion, what's going to happen when the physical properties of silicon can't sustain moore's law anymore

nothing, for two reasons

first some background: moore’s law states that every year the number of components (transistors) on integrated circuits will double (due to engineering breakthroughs). it has proved to be somewhat correct. it occurs due to our ability to manufacture smaller and smaller transistors which has a few effects, discussed later. eventually we will hit a point where it no longer matters how small we can print transistors as the fundamental electrical characteristics of silicon break down

in the next couple of years, we will see chips from intel with transistors printed about ten nanometers apart. we approach the limits silicon can handle, theoretically, around ~1nm

in circuits this small, you start seeing tunneling effects which are phenomenons of quantum physics wherein the propagation delay of charge falls to zero, meaning stimulation of the source terminal of a transistor would elicit a response on the drain terminal without any time elapsing. electrons just “blink” from one end of the xsistor to the other. you’d think this would be a good thing, but it isn’t. anyone with advanced physics degrees or deep VLSI knowlege is welcome to chime in why.

anyway

the first reason is there is no alternative to silicon. we have poured billions into researching things like gallium arsenide as a replacement for silicon in integrated circuits. it doesn’t work as well as silicon. people will try to convince you otherwise and those people are crackpots

we have poured a lot of time & money into researching quantum computers and discovered that they are only superior for very specific tasks such as brute-forcing encryption keys and other things of that nature. they will also probably never cost a billion dollars each to manufacture, never need anything less than a power plant and vats of liquid helium to operate, etc etc

the logical “next step” might be optical computing. here, you fundamentally change the hardware paradigm from electrons traveling through traces cut in a mediating silicon substrate between transistors to photons traveling through ?? mediated by ?? between “phototransistors”. the underlying principle is that light, in some cases, travels faster than voltage propagates through conductors. i’m going to get a lot of asks saying “durr kremlin but the speed of light is constant and i took high school physics and blah blah blah” and that’s a discussion worth its own post

this kind of tech is far off. not in our lifetime, not in your children’s lifetime, not in your children’s children’s lifetime

the reason we make transistors smaller is so we can pack them together more closely. this reduces the distance charge must travel in the circuit, making the cycles of these circuits take less time to complete. smaller transistors also generally necessitate less impedance and operate correctly at lower voltages, meaning their operating frequency can increase without a corresponding drop in reliability

these are all nice things, but they are only one piece of the puzzle. how you lay out these transistors is a much more critical and relevant problem. taking a previous VLSI design and shrinking it only works to a point after which you must redesign the layout entirely. intel’s “tick-tock” release/development department follows this model. long before and long after we hit the fundamental limits of silicon, the problem will be laying out our CPU circuits in such a way that we can actually eek out the performance provided by smaller transistors. this is a much, much harder problem to solve than “how do i make the transistor smaller”

the second, more pragmatic reason is that CPUs are fast enough already. there are scarce few problems that can be solved with faster discrete processors that can’t be solved with a million slower ones linked together

the whole tiny-transistor thing is really more of a marketing phenomenon than anything else

fav japanese vine so far

These “mammatus clouds” were photographed above Hastings, Nebraska, after a destructive thunderstorm in May 2005. Although their formation is not completely understood, these rare clouds usually develop at the base of a thunderstorm, and appear lumpy because of instabilities and temperature differences between sinking and rising air.