Physics in Action by Topic
Light & Optics
TESS: A Satellite Scout for Nearby Exoplanets
New worlds orbiting strange stars are waiting to be discovered...and we're on the hunt.
Imaging Forests for Environmental Assessments
Airborne spectroscopy allows scientists to collect data on forests at an unprecedented rate.
Neutron Stars: Cosmic Laboratories for Quantum Physics
Using light from a distant neutron star, scientists have observed a strange quantum phenomenon called vacuum birefringence.
Using Gold Nanoparticles to Kill Cancer
Lasers and nanoengineering team up to take on one of the deadliest diseases
Plasma Fairies: Femtosecond Laser Holograms
Lasers have enabled the creation of free-floating, interactive holograms!
Curiosity vs. Other Mars Missions
How do recent Mars missions compare to the popular Curiosity rover?
Pluto's Neighbor Could Float on Water
A Kuiper Belt object less dense than water has piqued scientists' interest
A Spin on Doppler
A twist on this physics principle can detect rotation in tornadoes, planets and more
Laser Speckle Patterns and Malaria
Of the five different parasites that cause malaria, one type can cause death within hours. Current methods of detecting malaria take between 8 and 10 hours. A new technique, developed by an international group, analyzes the speckle patterns of laser light reflected off of a blood sample with detection times of 30 minutes.
Super Efficient LEDs
More than 100% efficient, these Light Emitting Diodes (LEDs) put out more light energy than the electrical energy that they use!
Mind over matter, light over mind
Can lasers control your mind? Not exactly, but light can control the firing of neurons in the brain, and has been used to affect the behavior of mice.
The Advanced Light Source: Where Physics Lets Science Happen
The Berkeley Lab's Advanced Light Source produces x-rays a billion times brighter than the sun by flinging electrons around at nearly the speed of light. Find out how and the ways that scientists use these brilliant flashes of invisible light to probe the world of the unseen.
Ionizing Radiation and Humans – The Basics
In the wake of the Fukishima Nuclear Reactor incident, radiation is on the minds of many people, but did you know that people are exposed to radiation everyday? Ionizing radiation, like many things, isn’t bad unless a living organism is exposed to too much of it.
Record energies force new thoughts on lightning
Physicists using modern spacecraft have observed storms all over the planet and discovered that lightning can generate energies far in excess of what was previously thought possible. What's even more alarming is that some of them can generate anti-matter.
Nuclear Forensics and Unbaking the Cake
At our nation’s ports, cargo ships from all over the world, carrying goods from granite to rubber duckies, enter the United States. But how do we know what’s really in each cargo box and if it is safe? One safety check requires trucks to pass through radiation monitors to see if there is any radioactive substance in the cargo entering the country.
Holograms: Virtually Approaching Science Fiction
Hologram applications are still futuristic, but advances in holography are bringing us closer than ever to capturing holographic images in real time.
Stock Trades at the Speed of Light
What does the speed of light have to do with the stock market? When stock market trading time is of the essence some financially savvy physicists proposed a solution.
Infrared Light
What do night vision goggles, land mine detectors, and studies of the universe have in common? In some way, all of them are connected to a small range of light sandwiched between visible light and microwaves on the electromagnetic spectrum—infrared light.
Feynman Diagrams: The science of doodling
Every popular explanation of particle physics is liberally illustrated with cartoon-like pictures of straight and wiggly lines representing electrons, photons, and quarks, interacting with one another. These so-called Feynman diagrams were introduced by Richard Feynman in the journal Physical Review in 1949, and they quickly became an essential tool for particle physicists.
Optical Tweezers
Unwind a chromosome to see how it’s put together? Sort cells with a light beam? Make a model of a molecular motor? All these and more—welcome to the world of optical tweezers, where cells and even individual molecules are manipulated with laser light.
Through a Lens Darkly
What limits the sharpness of an image? The answer has to do with the wave nature of light.
Slow Light
Suppose you and a friend tried to measure the speed of light. You have a powerful flashlight and a stopwatch, and your friend has a mirror. You walk away until the two of you are 100 meters apart. You aim the flashlight at the mirror, turn the light on, and wait to see the reflection. How long do you have before the light gets back?
Ice Ages
In the controversy over global warming, some people have suggested that human-induced warming might be a good thing if it kept us out of the next Ice Age.
Catch a Cosmic Microwave
A trio of recent findings on cosmic microwave background radiation lends strong support to the idea that the entire observable universe was once smaller than an atom and underwent a "super-charged" Big Bang.
Deep Impact
Comets are relics from the origin of the solar system, carrying material about 4.5 billion years old.
CT Scans
William Roentgen made the first x-ray image in 1895, but the technology remained essentially the same until the late 1960s. These images were projected onto flat detectors, such as film or electronic sensors.
Seeing Atoms
What does it mean to see an atom? Suppose you tried to use the world’s strongest optical microscope to see an atom. What would happen?
Solar Flares
You may have seen the “northern lights” in the fall of 2003, even if you live as far south as Texas or Italy.
Sound, Lights, Action!
Sonoluminescence is a way to turn sound energy into light. When intense sound waves are created in a flask of water, a tiny air bubble in the water can give off flashes of light.
Laser Cooling and Trapping
Absolute zero, as cold as it gets, resides at the very bottom of the temperature scale.
Do You See What Eye See?
It’s been hard to miss the publicity for LASIK, the laser surgery that reshapes the cornea to improve the eye’s ability to focus.
