23 OCT 2013 by ideonexus

 Proof that Objects Fall at the Same Rate

Salv. But, even without further experiment, it is possible to prove clearly, by means of a short and conclusive argument, that a heavier body does not move more rapidly than a lighter one provided both bodies are of the same material and in short such as those mentioned by Aristotle. But tell me, Simplicio, whether you admit that each falling body acquires a definite speed fixed by nature, a velocity which cannot be increased or diminished except by the use of force [violenza] or resistance....
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Galileo's proof is based completely on a thought-experiment, no observation necessary.

03 OCT 2013 by ideonexus

 The Parameters of "Spaceship Earth"

Our little Spaceship Earth is only eight thousand miles in diameter, which is almost a negligible dimension in the great vastness of space. Our nearest star — our energy-supplying mother-ship, the Sun — is ninety-two million miles away, and the nearest star is one hundred thousand times further away. It takes approximately four and one third years for light to get to us from the next nearest energy supply ship star. That is the kind of space-distanced pattern we are flying. Our little Spa...
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Our place in the cosmos. This is the situation in which we find ourselves.

31 JUL 2013 by ideonexus

 Science Manipulates Language to Make it More Precise

Let us consider two spheres moving in different di- rections on a smooth table. So as to have a definite picture, we may assume the two directions perpendicu- lar to each other. Since there are no external forces acting, the motions are perfectly uniform. Suppose, further, that the speeds are equal, that is, both cover the same distance in the same interval of time. But is it correct to say that the two spheres have the same velocity? The answer can be yes or no ! If the speedo- mete...
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The example is "velocity" which in common parlance is the same as "speed," but in science it means "speed and direction."

28 MAY 2013 by ideonexus

 Actuarial Escape Velocity

actuarial escape velocity is defined as occurring when a year of medical research adds more than a year’s worth of longevity to the total population. Nothing even close to this has ever been achieved, and emerging signs of an asymptotic curve in progress suggest this velocity may never
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A medical concept, when medical research extends lifespans at a rate of more than one year per one year of research.