02 MAR 2019 by ideonexus

 Triangles on Earth Exceed 180 Degrees

The idea that space and time can be curved or warped is fairly recent. For more than 2,000 years the axioms of Euclidean geometry were considered to be selfevident. As those of you who were forced to learn geometry at school may remember, one of the consequences of these axioms is that the angles ot a triangle add up to 180 degrees. However, in the last century people began to realise that other forms of geometry were possible in which the angles of a triangle need not add up to i8o degrees...
Folksonomies: perception curved space
Folksonomies: perception curved space
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02 MAR 2019 by ideonexus

 The Anthropic Principle

As an example of the power of the Anthropic Principle, consider the number of directions in space. It is a matter of common experience that we live in three-dimensional space. That is to say, we can represent the position of a point in space by three numbers. For example, latitude. longitude and height above sea level. But why is space three-dimensional? Why isn't it two, or four, or some other number of dimensions, hke in science fiction? In fact, in M-theory space has ten dimensions (as wel...
Folksonomies: anthropic principle
Folksonomies: anthropic principle
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10 FEB 2018 by ideonexus

 Agency in Reading VS Gaming

Comparing computer play with reading fiction reveals much about thes^se shortcomings. Reading stimulates the mental recreation of settingg, characterers, a and acactiojons in viLxal, auditory, tactile, kinesthetic, and other sensory images. One "sees" the pirate h the scar slashing across his cheek. One "hears" the sail flapping in the wind. One "feels" the swell of the waves on ship deck. Perhaps one also "smells" the salt air. nd so on. The reader pulls all these sensory images together i...
Folksonomies: reading gaming agency
Folksonomies: reading gaming agency
  1  notes
 
22 MAR 2012 by ideonexus

 Pauli Exclusion Principle

In the three-dimensional space in which we live, elementary particles are designated as fermions and bosons, depending on their spin. We associate with each variety of elementary particle a quantum number, which gives the value of its spin. This number can be an integer (0,1, 2,... ) or a half integer (1/2, 3/2, 5/2,...). Particles with integer spin are called bosons, and particles with half integer spin are called fermions. The quantum mechanical behavior of fermions and bosons is different:...
Folksonomies: physics quantum physics
Folksonomies: physics quantum physics
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Two identical fermions cannot occupy the same quantum mechanical state.

12 DEC 2011 by ideonexus

 The Brain Creates Models of the World

We make models in science, but we also make them in everyday life. Model-dependent realism applies not only to scientific models but also to the conscious and subconscious mental models we all create in order to interpret and understand the everyday world. There is no way to remove the observer—us—from our perception of the world, which is created through our sensory processing and through the way we think and reason. Our perception—and hence the observations upon which our theories are...
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Using the eye as an example, Hawking describes how our brains model the outside world and builds theories about it.

08 JUL 2011 by ideonexus

 John Locke VS Babies

Another great English philosopher, John Locke, posed another classical epistemological problem. What would happen if you miraculously restored the sight of someone who had been blind from birth? Would that person recognize all the objects he had known so intimately through touch, or would he have to painstakingly learn that the smooth, hard, curved surface looked like a porcelain teacup, or that the familiar, soft, yielding swells and silky hairs translated into a visual wife? Locke thought t...
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Locke wondered if a blind person given sight would need to learn how to associate this new sense with the others, but babies make these associations instinctively.