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Games for Change

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Games for Change (also known as G4C) is a movement and community of practice dedicated to using digital games for social change. An individual game may also be referred to as a “game for change” if it is produced by this community or shares its ideals.

The Games for Change Festival

Since 2004, Games for Change has hosted the Games for Change Festival in New York. Often referred to as “the Sundance of Video Games”, the Games for Change Annual Festival is the biggest gaming event in New York City. It brings together leaders from government, corporations, philanthropy, civil society, media, academia, and the gaming industry to explore the increasing real-world impact of digital games as an agent for social change.

— Wikipedia on Games for Change

2012.06.24 Sunday ACHK

Life is boring

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A young person is as bored as an old person.

A young person’s life seems to be interesting

because he can imagine how interesting his life will be. 

— Me@2011.10.20

2012.06.22 Friday (c) All rights reserved by ACHK

Information lost, 3.2

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Information conservation

There is another very subtle law of physics that may be even more fundamental than energy conservation.

It’s sometimes called reversibility, but let’s just call it information conservation.

Information conservation implies that if you know the present with perfect precision, you can predict the future for all time.

But that’s only half of it. It also says that if you know the present, you can be absolutely sure of the past. It goes in both directions.

— The Black Hole War, p.87

— Leonard Susskind

2012.06.12 Tuesday ACHK

Mobile phones

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Perhaps most important, information can flow through even the remotest of villages, thanks to the massive increase in mobile telephones across regions that just a few years ago had no phones at all.

Mobile connectivity and the spread of wireless broadband are greatly strengthening rural health systems. In all of the Millennium Villages, and in more and more villages around the continent, lay community workers are bringing health services from the clinics right to the community. Mobile phones are critical in supporting these outreach workers, enabling them to call the doctors and nurses for advice, summon an ambulance or connect to a computerized expert system via text messaging.

— Global health within our grasp, if we don’t give up

— By Jeffrey Sachs, Special to CNN

2012.05.29 Tuesday ACHK

Proper nutrition

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Food provides nutrients from six broad classes: proteins, fats, carbohydrates, vitamins, dietary minerals, and water. Carbohydrates are metabolized to provide energy. Proteins provide amino acids, which are required for cell construction, especially for the construction of muscle cells. Essential fatty acids are required for brain and cell membrane construction. Vitamins and trace minerals helps to keep good electrolyte balance and are used for metabolic processes. Dietary fiber also affects one’s health, although it’s not digested into the body.

— Wikipedia on Dieting

2012.05.07 Monday ACHK

Single-world interpretation, 7

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One consequence is that every observation can be thought of as causing the combined observer-object’s wavefunction to change into a quantum superposition of two or more non-interacting branches, or split into many “worlds”.

— Wikipedia on Many-worlds interpretation

That is incorrect.

Let’s consider the double-slit experiment. For simplicity, we regard the event “a person reads the device reading” as a classical event.

Before installing the measuring device, we do not know which slit a photon goes through. The photon state is in a superposition of eigenstates: 

| photon > = a | left > + b | right >

(According to the meaning of probability, |a|^2 + |b|^2 = 1.) In other words, if we send enough such kind of photons through the double-slit apparatus, we get the interference pattern. 

After installing the measuring device, we know which slit a photon goes through. According to the Copenhagen interpretation, when the photon passes through the double-slit apparatus, the photon-state “collapses” to one of the two eigenstates, such as | left >. However, a more accurate point of view is that, according to the quantum decoherence interpretation, the photon-and-device state becomes a superposition of a lot of eigenstates. Most of such eigenstates are corresponding to the macrostate of passing-through-the-left-slit, |left>_macro_state. 

The above many-worlds-interpretation statement assumes that there is a |right>_macro_state.

It is true in a sense that, since the photon-and-device involves a lot of particles, there are so many eigen-microstates. Some are certainly corresponding to the |right>_macro_state.

It is false in a sense that the weighting of the |right>_macro_state is so small that such macrostate is not meaningful in a macroscopic context, for example:

| photon-and-device > = 10^23 |left>_macro_state + 0.001 |right>_macro_state + other possible macrostates

— Me@2012-04-07 11:03:12 AM

2012.04.09 Monday (c) All rights reserved by ACHK