Heinrich Rudolf Hertz, who was honored Wednesday on his 155th birthday, helped explain how even nothing at all can be something. ?
Today Google honors Heinrich Rudolf Hertz, the German physicist who, in his all-too-short career, taught the world invaluable lessons about optics, electromagnetism, and, in a contribution that is often overlooked,?the science of nothingness.
Skip to next paragraph"Horror vacui," goes the phrase, usually attributed to Aristotle's fourth book of Physics. Nature abhors a vacuum. True or not, it's certainly the case that those studying nature have long struggled with the concept of empty space. Aristotle thought that, because space empty of all matter offers no resistance, objects moving within it would move infinitely fast. Thus the objects surrounding any void would instantly fill it before it could form. Emptiness, he concluded, was therefore impossible. Every part of the universe must be filled with something, even if we can't detect it. ?
Aristotle's arguments persuaded scholars for a good 1,500 years or so. Medieval Christians were enjoined from entertaining the possibility of a vacuum, until the Catholic Church's Condemnations of 1277 broke Aristotle's monopoly on the natural sciences by admitting that, at the very least, a vacuum would not be beyond the powers of an omnipotent God.?
But even though contemplating empty spaces became theologically permissible, the idea of nothingness still proved troubling to early modern thinkers, even as others were setting about constructing pumps and siphons. In the seventeenth century, when Irish chemist Robert Boyle demonstrated his?"Pneumatical Engine"?and when French physicist Blaise Pascal developed a barometer, they were attacked by Thomas Hobbes and Ren? Descartes, who each embraced a philosophy known as plenism, which left no space for emptiness.
The plenists arguments were persuasive. Sure, they argued, you might be able to remove all the air from a glass tube, but how is it that, say, two magnets inside the tube will still attract one another, if there really is nothing?at all between them? How is it that electric fields can pass through the tube??
In the 19th century, after scientists firmly established that light travels in waves, scientists wondered how waves of light from the stars could ever reach the earth after traversing millions of miles of allegedly empty space. A wave, after all, needs something to ripple through, right?
Hertz initially complicated the picture even further, but his work also foretold a way out. While attempting to demonstrate the theories of Scottish physicist James Clerk Maxwell he conclusively demonstrated the existence of electromagnetic waves, and then caught a glimpse of how these waves act in very un-wavelike ways.
The Monitor's Chris Gaylord describes Hertz's famous?experiment:
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