San Antonio College Library

The story of how we use light to reveal the cosmos begins in the 3rd century BC with the Greek mathematician Euclid's discovery that light travels in straight lines-a discovery that meant that if we could change its path we could change how we see the world. In Renaissance Italy, 2,000 years later, Galileo Galilei did just that by using the lenses of his simple telescope to reveal our true place in the cosmos. With each new insight into the nature...

Professor Jim Al-Khalili meets scientists who are attempting to capture dark matter and finds out how it may be tearing the Universe apart.

Beyond the narrow range of light that makes up the familiar colors of the rainbow is a vast spectrum of light, entirely unseen. With the help of groundbreaking new imaging technologies we see the world, quite literally, in a whole new light. From ultraviolet cameras that seek out an invisible force that lurks unseen on power lines, to infrared images that reveal the secrets within a humble beehive.

Dispite popular belief, Edison did not invent the lightbulb--many people contributed to the invention. Mind you, the first lamp was invented around 70,000 BC. This program examines Edison's actual contribution of improving the lightbulb to become a practical, affordable, and safe product. Modern-day lighting innovations are quite startling, as many of them we can't even see with the naked eye. Consider lasers. Nobody knew what to make of this idea...

The story of the photoelectric effect is an ongoing one, from its discovery in 1887 to its use in a myriad of today's devices, such as cameras and cell phones. This program tells that story, charting the contributions of Hertz, Lenard, Planck, and Einstein, while making use of actual experiments, clever demonstrations, and formulas that describe each aspect of a crucial physics phenomenon. Topics include: Hertz's initial experiment; Lenard's investigations;...

Is light composed of waves or particles? This collection of 17 computer-animated video modules explores the wave model of light, from its earliest roots to our modern understanding of electromagnetism. Empedocles' belief that light streams from the eye, Aristotle's conception of light as a disturbance in ether, and Euclid's mathematical, ray-centered paradigms are all explored. The Cartesian sine wave model, Huygens' principle of bending wave fronts,...

What is light? How does it function? Why is it so important to the foundations of the physical world? This program examines the nature of light and applications of its properties. The basic principles of light waves-propagation, reflection, and refraction-are explained, and information about lenses, the electromagnetic spectrum, and total internal reflection is illustrated using the human eye, rainbows, and raindrops as examples. Common applications,...

This program examines the use of lasers and optical fibers as a means of providing high-bandwidth communications. The underlying principles of physics are thoroughly explained, the chemical and engineering challenges faced in providing improved data transfer are explored, and examples of applied photonics-both present and future-are examined. Expert commentary and 3-D computer animations enhance the program.

This program addresses light speed and the phenomena it enables, as well as ways scientists envision breaking the "light barrier." Could the interstellar travel of science fiction one day become a reality?

Uses demonstrations and animation, to delve into the fundamental concepts of reflection and its relationship to light, vision, and the physical world. Topics include: What is reflection? How do mirrors form images? How do they reflect light differently depending on their properties? In what way are mirror images different from two-dimensional photographs? How does our ability to see in three dimensions affect the way we see mirror images? Can animals...