Defense Advanced Research Projects AgencyTagged Content List

Fundamental Physical Science

Pushing the boundaries of knowledge of the physical sciences

Showing 109 results for Fundamentals RSS
The explosive growth of global digital connectivity has opened new possibilities for designing and conducting social science research. Once limited by practical constraints to experiments involving just a few dozen participants-often university students or other easily available groups-or to correlational studies of large datasets without any opportunity for determining causation, scientists can now engage thousands of diverse volunteers online and explore an expanded range of important topics and questions.
Lightning can cause delays in operations, disrupt communications, destroy assets, and generally pose a deadly threat to military personnel. While lightning has been studied intermittently for decades, critical questions remain about how and why lighting initiates, how it spreads, and how it attaches to objects. Also unclear is how lightning generates its ionospheric components such as elves, sprites, and gigantic blue jets, or how it ties into the global charging circuit.
Defense applications, such as geo-location, navigation, communication, coherent imaging and radar, depend on the generation and transmission of stable, agile electromagnetic radiation. Improved radiation sources—for example, lower noise microwaves or higher flux x-rays—could enhance existing capabilities and enable entirely new technologies.
Typically, the performance of measurement devices is limited by deleterious effects such as thermal noise and vibration. Notable exceptions are atomic clocks, which operate very near their fundamental limits. Driving devices to their physical limits will open new application spaces critical to future DoD systems. Indeed, many defense-critical applications already require exceptionally precise time and frequency standards enabled only by atomic clocks. The Global Positioning System (GPS) and the internet are two key examples.
Biological sensors often display high sensitivity, selectivity, and low false alarm rates while being fabricated and operated in dirty, noisy natural environments. Attempts to emulate these sensors synthetically have not fully met expectations. Recent evidence suggests that some biological sensors exploit nontrivial quantum mechanical effects to produce macroscopic output signals. Examples of such sensors include the highly efficient energy transfer properties of photosynthesis in plants, bacteria, and algae; magnetic field sensing used by some birds for navigation; and the ability of some animals to detect odors at the single molecule level.