25 OCT 2017 by ideonexus

 Blockchains

Ownership on the Bitcoin blockchain is determined by a pair of cryptographic keys. The first, called the public key, resides in the blockchain for anyone to see. The second is called the private key, and its owner keeps it safe from view. The two keys have a special mathematical relationship that makes them useful for signing digital messages. Here’s how that happens: Helmut takes a message, combines it with his private key, does some calculations, and ends up with a long number. Anyone who...
Folksonomies: blockchains technology
Folksonomies: blockchains technology
  1  notes
31 MAY 2015 by ideonexus

 Flatland Science: Dimensions

What and where is Flatland? A Square gives us several interesting answers, many of th contradictory. We know that it’s flat, big (but how big?), and very thin, the most important question of all is “how thin?” A lot depends on the answer… A Square himself eliminates the version that’s easiest for three-dimensional readers to understand; a world that’s thin – maybe only a few atoms thick - but nevertheless has some physical height. It would have some sort of solid or semi-solid ...
Folksonomies: science fiction otherness
Folksonomies: science fiction otherness
  1  notes
 
24 JAN 2015 by ideonexus

 Humanity is Not the Purpose of the Universe, It is Humani...

Another phrase which occurs frequently in the propaganda of Christian fundamentalists is "scientific humanism." Scientific humanism is supposed to be a philosophy standing in opposition to Christian faith. Fundamentalists like to pretend that we have only two alternatives, either scientific humanism or their version of Christianity. But scientific humanism has as many different meanings as scientific materialism. Roughly speaking, a scientific humanist is somebody who believes in science and ...
Folksonomies: humanism
Folksonomies: humanism
  1  notes
 
31 JAN 2012 by ideonexus

 Stephen Chu's Pendulum High School Experiment

For the better part of my last semester at Garden City High, I constructed a physical pendulum and used it to make a 'precision' measurement of gravity. The years of experience building things taught me skills that were directly applicable to the construction of the pendulum. Twenty-five years later, I was to develop a refined version of this measurement using laser-cooled atoms in an atomic fountain interferometer.
Folksonomies: experiment science fair
Folksonomies: experiment science fair
  1  notes

He used the pendulum to make a precise measurement of gravity, and the process would eventually inform his Nobel Prize winning work.

03 JAN 2012 by ideonexus

 Creating Online Fictions of Ourselves

The most effective young Facebook users, however—the ones who will probably be winners if Facebook turns out to be a model of the future they will inhabit as adults—are the ones who create successful online fictions about themselves. They tend their doppelgängers fastidiously. They must manage offhand remarks and track candid snapshots at parties as carefully as a politician. Insincerity is rewarded, while sincerity creates a lifelong taint. Certainly, some version of this principle exi...
  1  notes

Lanier suggests that the most effective users of Facebook will manage their profiles like politicians, constructing a narrative that may have no baring on their real persona.

19 MAY 2011 by ideonexus

 Mendelian Genes are All-Or-Nothing

A Mendelian gene is an all-or-nothing entity. When you were conceived, what you received from your father was not a substance, to be mixed with what you received from your mother as if mixing blue paint and red paint to make purple. If this were really how heredity worked (as people vaguely thought in Darwin's time) we'd all be a middling average, halfway between our two parents. In that case, all variation would rapidly disappear from the population (no matter how assiduously you mix purple ...
Folksonomies: genes inheritance mendel
Folksonomies: genes inheritance mendel
  1  notes

Genes are on-off switches, carrying either mother or father's version of it, not a blend of the two.