Some materials can absorb low-energy light and emit high-energy radiation

Light can be used to slow the motion of atoms

While photons possess energy, they also have momentum, which allows them to collide with other particles, much like billiard balls, thereby slowing them down and reducing their kinetic energy, or temperature. Using multiple lasers from different directions, particles can be cooled to within one degree of absolute zero.

Microchip fabricators create light by heating tin droplets to over 220,000 Kelvin

Every second, lasers strike 50,000 droplets moving at 250 kilometers (155 miles) per hour, vaporizing the tin in supernova-like miniature explosions that produce ultraviolet light. Knowing this light will spread via diffraction as it passes through a filter during manufacturing, designers reverse-engineer the filter design based on the required final microchip pattern.

Stimulating electrons to emit identical photons produces lasers

This effect was predicted by Albert Einstein in 1917, and requires all excited electrons in a material to exist in the same excited metastable state within their atoms. Pumping all atoms through the same mechanism, such as electricity or flash lamps, can create this environment.

Thermodynamics makes building data centers in space to cool equipment impractical

Rather than cooling via interactions with flowing cold air or water, data centers in space would dissipate energy primarily by radiation, in which an object at any temperature above absolute zero emits light. This method is much less efficient at cooling and would require hyperscale data centers to have radiator panels thousands of times larger than those on the International Space Station.

Underwater data centers may provide an alternative to energy-intensive air cooling

By submerging electronic hardware into a non-conductive fluid, such as an oil with strong thermal transfer properties, significant thermal energy can be quickly drawn away from a chip and brought to the surface as warm materials rise. Thermal energy can then be removed from the fluid with a heat exchanger before it is recirculated.

Synthetic diamonds may be used to cool microchips

The strong carbon bonds in diamonds efficiently carry vibrations, allowing them to conduct heat several times faster than copper, a metal commonly used in heat sinks. AI and high-performance computing have pushed researchers to investigate alternative materials for cooling solutions.

Lasers are classified based on their gain medium and mode of emission

All lasers possess a material whose atoms must be energized by a power source, such as electricity or chemical reactions. Different media will produce different colors of light through a cascade of emissions resulting from an initial stimulated emission.

Random lasers can be created from biomaterials, such as peanuts and birch leaves

Rather than creating a narrow beam of light via amplification in an optical cavity, the random laser produces a red glow by scattering photons created in the natural pores of a peanut kernel after it has been injected with a solution of light-generating carbon dots derived from birch leaves.

Laser technology powers communication, medical and manufacturing tools

Lasers are used when scanning groceries, printing documents or undergoing cosmetic procedures to enhance efficiency, precision and accuracy. Missile defense, targeting and optical communication systems have made using laser technology habitual in the military.

Chromium contaminants in a ruby crystal gave the world's first laser its red color

The red light originates from a long-lasting excited electron state in the element's atomic structure. The brittle gray metal has historically been used in pigment production, the manufacturing of rust-resistant stainless steel, and the creation of durable coatings with long-lasting shine for metals, wood, and leather.

Photonic integrated circuits use light instead of electrons within circuit components

Instead of processing electric signals, photons in the visible and near-infrared serve as optical signals between chips made of electro-optical crystals. PICs can enable lower power consumption and heat generation by eliminating the friction from electrons moving along wires.

A laser energy system has allowed scientists to achieve fusion ignition

In 2022, scientists used lasers to create a powerful implosion that bound hydrogen isotopes together, releasing more energy than was input into the system. Research is ongoing to achieve this self-sustaining reaction with larger yields and energy gains.

Scientists have diverted the path of lightning using lasers

A proof of concept for a laser protection system, which could be used to protect launchpads and airports in the future, was conducted on the Säntis mountain in northeastern Switzerland. Rapid laser pulses heated air molecules, creating a more conductive, 50-meter (164-foot) path for the electrical discharge to travel through.

How scientists determine elemental composition based on the light emitted by cooling atoms

When electrons within an atom drop to a lower energy level closer to the nucleus, they lose energy and produce light with energy equal to the difference between the two energy levels. Because these levels and the corresponding emitted light are unique to each element, the light serves as a unique signature that can be compared to known lab samples for identification.

Images of quantum computers often depict dilution refrigerators

While quantum computers themselves can have a microchip of silicon spin qubits or other trapped particles that make up quantum computing's basic unit, these components are too small to see on their own. However, such chips are located at the base of chandelier-shaped machines that keep temperatures near absolute zero.

Variations in the energy of light force the use of multiple telescopes

Just as Earth's atmosphere allows the sun's visible light to pass through while blocking other harmful radiation, telescope mirrors and other optics can only reflect, absorb, or transmit certain types of light. Detectors also utilize semiconducting materials that react to specific energies of light, thereby preventing a one-telescope-fits-all solution.

Removal of different color tattoo inks may require multiple lasers

Light needs to be absorbed by ink particles to break them down into small enough pieces for the immune system to eliminate. Color ink reflects, rather than absorbs, lasers of the same color, while black ink absorbs all colored lasers.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

Laser disc technology stores binary data in etched pits and lands

The pits are dips in the LaserDisc, CD, DVD, or Blu-ray surface that do not reflect the laser from the optical drive back to the photoelectric cell, resulting in a coded zero. Lands are reflective plateaus on the surface that code for a one.

Infrared light is most often associated with thermal radiation and cooking food

Although extensively used in remote controls for electronics, where LED lights send signals wirelessly, infrared cameras allow for night vision and thermography—imaging of heat patterns in the body to non-invasively reveal blood flow for supplementary diagnostics. Infrared radiation also provides heat in toasters, saunas, and other technologies.

How cosmic rays and pointed ice shards help generate lightning in clouds

Although clouds generate electric fields as electrons are transferred when currents move past one another—not unlike building up static electricity by rubbing socks against carpet—these fields have been measured to be a tenth of the strength needed to make electricity strong enough to travel through air. However, pointed crystals are estimated to boost fields by factors greater than 10, and particles from outer space may help initiate cascades of displaced electrons.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

How helium enables MRI machines to look inside organisms

By cooling the machine's magnets with liquid helium to extremely low temperatures, they can generate and maintain powerful magnetic fields that align the hydrogen atoms in living things to point toward a patient's head or feet. A radio pulse nudges these atoms, which realign and induce a measurable signal in nearby electrical coils. These signals are captured in slices and then stacked into a 3D reconstruction.

Understanding why the thermosphere feels cold, despite exceeding 2,000 degrees Celsius

High-energy solar radiation can raise temperatures above 2,000 degrees Celsius (3,632 degrees Fahrenheit), but the air density in this layer is so low that there would be insufficient collisions between energized molecules and a person's skin to cause them to experience this warmth. Variations in the level of solar radiation reaching the layer cause it to swell and shrink.

Watch a demonstration of the greenhouse effect in carbon dioxide

Some online experiments involving glass containers of air and carbon dioxide show no temperature differences upon exposure to infrared light because glass blocks that type of radiation. Using plastic bags, carbon dioxide can be demonstrated to absorb infrared radiation, thereby trapping energy and confirming its role as a greenhouse gas.

Fast charging can lead to battery degradation if the device does not stay cool

Modern phones use software to monitor charging habits and can activate adaptive charging to delay charging rates and prevent overheating. When charging, devices should not be confined (e.g., stored in your pocket) or placed in direct sunlight, as this can trigger heat warnings and sudden shutdowns.

Stars appear to twinkle because turbulence in the motion of molecules in Earth's atmosphere causes light to bend and wiggle rapidly on its way to the surface—a phenomenon called scintillation.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

Dirty lightning is a thunderstorm created from friction between rising and falling flows of ash and smoke during volcanic eruptions.

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

Tattoos remain visible on your skin thanks to immune cells called macrophages

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

Hedge funds, the private investment firms that trade a wide swath of financial assets, make money by imposing steep fees on investors and from the fund's investment performance.

Fast-casual restaurant Chili's is experiencing a resurgence, with its parent company recently reporting a nearly 32% increase in sales, thanks to passionate Gen Z fans on TikTok.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO