Issues
Search and Discovery
Lovely as a Tree Amplitude: Hidden Structures Underlie Feynman Diagrams
String theory, Fourier-conjugate spinors, and quantum chromodynamics are linked in ways that suggest new methods to compute probability amplitudes for high-energy particle interactions.
A Dark-Horse Entry in the Race for an Excitonic Condensate
Evidence for a superfluid made of electron-hole pairs comes, surprisingly, from quantum Hall systems.
Letters
Issues and Events
Taking Measure With Hardware and Software
The researchers who founded National Instruments Corp switched from building their own equipment to beefing up other people’s.
Science Board Warns of Uncertain Future for US Science and Engineering Leadership
The diminishing level of “native talent” entering science and engineering in the US is one of several factors that could significantly limit the country’s R&D leadership.
Articles
Dusty Plasmas in the Laboratory, Industry, and Space
Charged microparticles are an annoyance in the plasmas of fusion energy schemes and semiconductor manufacturing. But in laboratory plasmas and in space, they can be uniquely informative.
Lorentz Invariance on Trial
Precision experiments and astrophysical observations provide complementary tests of Lorentz invariance and may soon open a window onto new physics. They have already constrained models of quantum gravity and cosmology.
Basic Choices and Constraints on Long-Term Energy Supplies
Population growth and energy demand are exhausting the world’s fossil energy supplies, some on the timescale of a single human lifespan. Increasingly, sharing natural resources will require close international cooperation, peace, and security.
Thoughts on Long-Term Energy Supplies: Scientists and the Silent Lie
The worlds population continues to grow. Shouldnt physicists care?