Galileo’s experiment on falling objects

In the late 1500’s, everyone knew that heavy objects fall faster than lighter ones. After all, Aristotle had said so. That an ancient Greek scholar still held such sway was a sign of how far science had declined during the dark ages.

Galileo Galilei, who held a chair in mathematics at the University of Pisa, was impudent enough to question the common knowledge. The story has become part of the folklore of science: he is reputed to have dropped two different weights from the town’s Leaning Tower showing that they landed at the same time. His challenges to Aristotle may have cost Galileo his job, but he had demonstrated the importance of taking nature, not human authority, as the final arbiter in matters of science.
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Young’s double-slit experiment applied to the interference of single electrons

Though it is not simply made of particles, neither can it be described purely as a wave. In the first five years of the 20th century, Max Planck and then Albert Einstein showed, respectively, that light is emitted and absorbed in packets — called photons. But other experiments continued to verify that light is also wavelike.

It took quantum theory, developed over the next few decades, to reconcile how both ideas could be true: photons and other subatomic particles — electrons, protons, and so forth — exhibit two complementary qualities; they are, as one physicist put it, ”wavicles.”

Assuming the earth is spherical, its circumference spans 360 degrees. So if the two cities are seven degrees apart, that would constitute seven-360ths of the full circle — about one-fiftieth. Estimating from travel time that the towns were 5,000 ‘’stadia” apart, Eratosthenes concluded that the earth must be 50 times that size — 250,000 stadia in girth.

One of your first “Stuff Happens” episodes is about breakfast. What’s so special about breakfast and the environment?
Are you kidding? It’s the most important meal of the day. It had the iconic story that North American pigs - from where we get bacon - I presume unwillingly are fed feed made with South American anchovies (and herrings and sardines). Farmers say eating fish helps their animals grow to that wonderfully ample size consumers want. Because of this, we’re accidentally destroying an ecosystem. It’s the story of stories.

How so?
We’re seriously depleting the world’s anchovy population and leaving the penguins and South American seabirds with nothing to eat. These birds are dangerously close to starving because the anchovy and sardine populations have been decimated.

What can we do?
Strange as it may seem, you could eat more anchovies. This would raise the price of the fish and make anchovy fish feed more costly and less desirable to pig farmers. Also eat organic bacon from pigs raised on 100% agricultural feed. If you’re looking for the true organic meat products, make sure it’s grass-fed only.

Dolphins do sleep, but not quite in the same way that people do. They sleep with one half of the brain at a time and with one eye closed. Dolphins rest this way on and off throughout the day, switching which side of the brain they shut down. During these periods, everything inside the dolphin slows down, and the mammal moves very little.

The widely-held perception that the influenza vaccination reduces overall mortality risk in the elderly does not withstand careful scrutiny, according to researchers in Alberta. The vaccine does confer protection against specific strains of influenza, but its overall benefit appears to have been exaggerated by a number of observational studies that found a very large reduction in all-cause mortality among elderly patients who had been vaccinated.

The study included more than 700 matched elderly subjects, half of whom had taken the vaccine and half of whom had not. After controlling for a wealth of variables that were largely not considered or simply not available in previous studies that reported the mortality benefit, the researchers concluded that any such benefit “if present at all, was very small and statistically non-significant and may simply be a healthy-user artifact that they were unable to identify.”
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“Over the last two decades in the United Sates, even while vaccination rates among the elderly have increased from 15 to 65 percent, there has been no commensurate decrease in hospital admissions or all-cause mortality

Stanford computer scientists have developed an artificial intelligence system that enables robotic helicopters to teach themselves to fly difficult stunts by watching other helicopters perform the same maneuvers.
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The dazzling airshow is an important demonstration of “apprenticeship learning,” in which robots learn by observing an expert, rather than by having software engineers peck away at their keyboards in an attempt to write instructions from scratch.
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It might seem that an autonomous helicopter could fly stunts by simply replaying the exact finger movements of an expert pilot using the joy sticks on the helicopter’s remote controller. That approach, however, is doomed to failure because of uncontrollable variables such as gusting winds.