Physics for the 21st Century logo

Visuals: Graphics

2dF Galaxy Redshift Survey
Galactic studies such as the "2dF Galaxy Redshift Survey" will improve our understanding of the distribution of dark and normal matter. (Unit: 10)
Abundance of Light Elements
The abundance of light elements indicates that most of the universe is not protons, neutrons, or electrons. (Unit: 11)
Acceleration and Gravity
A person in an accelerating rocket feels the same downward pull as a person on Earth feels from gravity. (Unit: 3)
Accreting Black Hole
Artist's conception of a black hole accreting matter from a companion star. (Unit: 4)
AdS/CFT Duality
The AdS/CFT duality relates a theory on the boundary of a region to a theory with gravity in the interior. (Unit: 4)
Angle-resolved photoemission spectroscopy (ARPES) is a direct experimental technique to observe the distribution of the electrons (more precisely, the density of single-particle electronic excitations) in the reciprocal space of solids. (Unit: 8)
Atom Refrigerator Sketch
Sketch of experimental setup used to created ultracold atoms. (Unit: 7)
Atomic Fountain
Schematic diagram of an atomic fountain clock. (Unit: 5)
BCS Quasiparticle Formation
An illustration of the process by which a BCS quasiparticle becomes a mixture of a normal state quasiparticle and quasihole and in so doing acquires an energy gap. (Unit: 8)
BEC Oscillations
Super-oscillations of a quantum gas and their dissipation on heating. (Unit: 6)
Bending of Light
Bending of light in an accelerating rocket. (Unit: 3)
Beta Decay
An example of beta decay. (Unit: 2)
Beta Decay Spectrum
Beta decay spectrum: The puzzling process explained by the detection of the neutrino. (Unit: 1)
Binary Pulsar Decay
Orbital period of the binary neutron star system PSR 1913+15 measured from 1975 to 2000. (Unit: 3)
Binding Site Logo
This sequence logo is a compact way of displaying information contained in a piece of genetic material. (Unit: 9)
Bits and Binary Numbers
Classical computers use bits that can be valued either 0 or 1. (Unit: 7)
Black Hole Jet
This VLBI image of jets from a black hole could not have been produced without atomic clocks. (Unit: 5)
Blackbody Spectra
The spectrum of blackbody radiation at different temperatures. (Unit: 6)
Bohr's Model of the Atom
Model of the atom by Niels Bohr. (Unit: 5)
Bose Condensate
Atoms in a Bose condensate at 0 K. (Unit: 6)
Bose-Einstein Condensation
Some of the first experimental evidence for a gaseous macroscopic quantum state. (Unit: 6)
Bose-Einstein Condensation
Three stages of cooling, and a quantum phase transition to a BEC. (Unit: 6)
Bosons and Fermions
Atoms in a trap at 0 K: bosons form a BEC (left) and fermions form a degenerate Fermi gas (right). (Unit: 6)
Brane Inflation
A brane and an antibrane moving toward one another and colliding could have caused inflation and the Big Bang. (Unit: 4)
Branes and Strings
Strings can break open and end on a brane. (Unit: 4)
Carrying Around Light Pulses
Turning light into matter in one Bose-Einstein condensate and then matter back into light in a second BEC in a different location. (Unit: 7)
Causal Dynamical Triangulation
Causal Dynamical Triangulation builds the spacetime in which we live from tiny triangles. (Unit: 3)
Classic Michelson Interferometer
The Michelson interferometer now finds application in a 21st century experiment: the search for gravitational waves. The diagram shows the original version of the instrument. (Unit: 3)
Combined Evidence for Dark Energy
Combining evidence from supernova and the CMB makes a strong case for dark energy. (Unit: 11)
Coming Full Circle
Was Newton right after all: "Are not gross Bodies and Light convertible into one another... ?" (Unit: 7)
An extra dimension can curl up in a manner that is nearly impossible to discern for an inhabitant of the larger, uncurled dimensions. (Unit: 2)
Compactified Extra Dimension
String theorists generally believe that extra dimensions are compactified, or curled up. (Unit: 4)
Complex Adaptive Behavior
A schematic view of what constitutes a complex adaptive system. (Unit: 9)
Complex Quantum Wave
While the complex part of a quantum wavefunction "waves," the probability density does not. (Unit: 6)
Components of the Universe
The composition of the universe, with 96 percent invisible and unfamiliar. (Unit: 11)
Composite Fermions and Bosons
Protons in LHC collisions (left) and electrons in a superconductor (right) are examples of composite fermions and bosons. (Unit: 6)
Composite Higgs
This Feynman diagram representing a composite Higgs and top quark is a part of the Higgs mass calculation in a supersymmetric model. (Unit: 2)
Compton Scattering
Arthur Holly Compton (left) discovered that the frequency of light can change as it scatters off of matter. (Unit: 2)
Computer Schematic
Schematic of a modern digital computer. (Unit: 9)
Conserved Charge
The total amount of electric charge is conserved, even in complicated interactions like this one. (Unit: 2)
Constituents of the Universe
The composition of the universe, with 96 percent invisible and unfamiliar. (Unit: 10)
Cosmic Microwave Background
Map of the temperature variations in the cosmic microwave background measured by the WMAP satellite. (Unit: 10)
Cosmic Microwave Background
Dark energy is now the dominant factor pushing the universe to expand. (Unit: 11)
Cosmic Microwave Background
Map of the temperature variations in the cosmic microwave background measured by the WMAP satellite. (Unit: 4)
Cosmic Microwave Background Spectrum
Spectrum of the cosmic microwave background radiation. (Unit: 5)
Creation of the Earliest Elements
This series of reactions created the lightest elements in the infant universe. (Unit: 10)
Cuprate Superconductors
A candidate phase diagram based, in part, on magnetic measurements of normal state behavior, for the cuprate superconductors. (Unit: 8)
Curved Spacetime
Triangles on curved surfaces. (Unit: 3)
Density and Geometry
The geometry of the universe depends on its density. (Unit: 11)
Detecting the Direction of the WIMP Wind
If they exist, WIMPs could stream toward Earth in a specific direction in a "WIMP wind" that might be experimentally detectable. (Unit: 10)
Diffraction in Random Media
Diffraction of green laser light passing though a random medium. (Unit: 6)
Diffraction of Atoms
This diffraction pattern appeared when a beam of sodium molecules encountered a series of small slits, showing their wave-like nature. (Unit: 5)
Discovering Quarks at the SLAC
Overview of the Stanford Linear Accelerator Center. (Unit: 1)
DNA Configurations
The DNA double helix, in three of its possible configurations. (Unit: 9)
Doppler Cooling
Red-detuned lasers don't affect an atom at rest (left) but will slow an atom moving towards the light source (right). (Unit: 5)
Early Periodic Table
An early version of Mendeleev's Periodic Table, showing the positions of missing elements. (Unit: 6)
Effective Interaction
The net effective interaction between electrons in a metal. (Unit: 8)
Einstein's Gravitational Warp
In Einstein's theory of general relativity, mass warps the fabric of space. (Unit: 11)
Electromagnetic Spectrum
The electromagnetic spectrum from radio waves to gamma rays. (Unit: 5)
Electron Interference
An interference pattern builds up as individual electrons pass through two slits. (Unit: 5)
Electronic Band Structure
Comparison of the electronic band structures of metals, semiconductors, and insulators. (Unit: 8)
Electrostatic and Gravitational Shielding
Comparison of the shielding of electrostatic and gravitational forces. (Unit: 3)
Elementary Particles
This chart shows the known fundamental particles—those of matter and those of force. (Unit: 2)
Energy Landscape
Here, we see two possible paths across an energy landscape strewn with local minima. (Unit: 9)
The enzyme on the left has a much easier time reading DNA than the enzyme on the right due to structural details that are difficult to predict from first principles. (Unit: 9)
Equivalent String Configurations
The consequences of strings winding around a larger extra dimension are the same as strings moving around a smaller extra dimension. (Unit: 4)
Evaporative Cooling
Evaporative cooling into the ground state. (Unit: 7)
Expanding Universe
General relativity is consistent with all the cosmological data that characterizes our visible universe. (Unit: 4)
Expanding Universe
If we run time backwards, the entire universe collapses into a single, infinitely dense point. (Unit: 4)
Experimental Limits on ISL Violations
Experimental limits on the universality of free fall. (Unit: 3)
Experimental Setup for Slow Light
Experimental realization of slow light. (Unit: 7)
Extra-Dimensional Space
A depiction of one of the six-dimensional spaces that seem promising for string compactification. (Unit: 4)
Fermi Gamma-ray Space Telescope
NASA's Fermi Gamma-ray Space Telescope has spotted an excess of normal matter particles that may have arisen when WIMPs annihilated each other. (Unit: 10)
Fermi Surface with Holes and Electrons
The Fermi surface reveals how the energy varies with momentum for the highest-energy electrons—those that have the Fermi energy. (Unit: 8)
Feynman Diagram of a Jet
In this Feynman diagram of a jet, a single quark decays into a shower of quarks and gluons. (Unit: 2)
Feynman diagrams
Feynman diagram representing a simple scattering of two particles (left) and a more complicated scattering process involving two particles (right). (Unit: 2)
Fitness Landscape
Natural selection can be viewed as movement on a fitness landscape. (Unit: 9)
Friction, Close Up
A microscopic view of friction. (Unit: 2)
Frustrated Spin System
This simple system of three spins is frustrated, and has no clear ground state. (Unit: 9)
Fundamental Particles
Three generations of quarks and leptons. (Unit: 1)
Galactic Case for Dark Matter
Observed and predicted rotation curves for the galaxy M33, also known as the "Triangulum Galaxy." (Unit: 10)
GRACE Mission
GRACE mission gravity map of the Earth. (Unit: 3)
Gravitational Attraction
Gravitational attraction between two spheres causes a tiny change in their positions. (Unit: 3)
Gravitational Field Lines
The gravitational field lines spread out radially from a massive particle. (Unit: 4)
Gravitational Wave Detector
Schematic of a laser interferometer that can detect gravitational waves. (Unit: 2)
Gravitational Waves
Distortion of space from a gravitational wave. (Unit: 3)
Graviton Exchange
Gravitons arise naturally in string theory, leading to Feynman diagrams like the one on the right. (Unit: 4)
Gravity and Extra Dimensions
Gravity leaking into extra dimensions could explain the hierarchy problem. (Unit: 4)
Ground State of Helium
The ground state of helium: energy levels and electron probability distribution. (Unit: 6)
Harmonic Oscillator
A simple harmonic oscillator (bottom) and its energy diagram (top). (Unit: 5)
Harmonic Oscillator Energy Levels
Low-lying energy levels of a harmonic oscillator. (Unit: 5)
Harmonic Oscillator, n=40
The wavefunction (left) and probability distribution (right) of a harmonic oscillator in the state n = 40. (Unit: 5)
Hawking Radiation
Black holes radiate by a quantum mechanical process. (Unit: 4)
Helium Atom
Mass of a helium atom is not equal to the sum of its constituent parts. (Unit: 3)
Helium Isotopes
The two isotopes of helium: a fermion and a boson. (Unit: 6)
Helium Phases
Temperature-pressure phase diagrams of the two quantum materials, 3He and 4He, that remain liquid down to the lowest temperatures in the absence of pressure compared to a typical liquid-solid phase diagram. (Unit: 8)
Horizon Problem
Both sides of the universe look the same, although light could not have traveled from one side to the other. (Unit: 4)
Hubble Diagram
Hubble diagram, plotting velocity vs. distance for galaxies outside our own. (Unit: 11)
Hydrogen Atom
The size of a hydrogen atom is determined by the uncertainty principle. (Unit: 5)
Hydrogen Spectrum
The spectrum of atomic hydrogen. (Unit: 5)
During the period of inflation, the universe grew by a factor of at least 1025. (Unit: 4)
Inflaton Potential
A potential like the one shown above for the inflaton field could have caused inflation. (Unit: 4)
INS and Phonon Spectrum
Top: Experimental set-up for measurement of energy loss spectrum of neutrons that are inelastically scattered by a crystal. Bottom: A typical phonon spectrum obtained through an elastic neutron scattering (INS) experiment. (Unit: 8)
Interfering Bose-Einstein Condensates
Interference of two coherent BECs, separated and allowed to recombine. (Unit: 6)
Internal Energy Levels of a Sodium Atom
Internal, quantized energy levels of the atom. (Unit: 7)
Inverse Beta Decay
The inverse beta decay that revealed the neutrino. (Unit: 1)
Joint Dark Energy Mission
The Joint Dark Energy Mission will make precise measurements of the effects of dark energy from space. (Unit: 11)
Kaon-Box Diagram
Neutral kaon oscillation. (Unit: 1)
Kondo Lattice Scaling Behavior
A candidate phase diagram for CeRhIn5 depicting the changes in its emergent behavior and ordering temperatures as a function of pressure. (Unit: 8)
Length Scale
Quantum effects meet general relativity somewhere near the center of this length scale. (Unit: 4)
Lewis Shell Model
The Lewis shell model for the first three atoms in the modern periodic table. (Unit: 6)
Li, Na, and K Energy Levels
Electrons in atomic energy levels for Li, Na, and K. (Unit: 6)
Light Curves
Light curve shape standardization. (Unit: 11)
LISA Satellites
Artist's conception of the LISA satellites in space. (Unit: 3)
Loop Quantum Gravity
Visualization of a stage in the quantum evolution of geometry, according to Loop Quantum Gravity. (Unit: 3)
LUX Detector
The Large Underground Xenon detector will have 100 times more sensitivity to WIMPs than previous detection methods. (Unit: 10)
Magnetic Interaction
Magnetic interaction potential in a lattice. (Unit: 8)
Magnetic Quasiparticle Interaction
The magnetic quasiparticle interaction between spins s and s'. (Unit: 8)
Matter and Antimatter
Matter and antimatter: An imperfect mirror. (Unit: 1)
Measurement of Ultra-Slow Light
Measurement of ultra-slow light in a cold atom cloud. (Unit: 7)
Mesons and Baryons
The periodic table for heavier mesons and baryons. (Unit: 1)
Mirror Symmetry
For the weak force, an electron's mirror image is a different type of object. (Unit: 2)
Models of the Universe
The future scale of the universe depends on the nature of dark energy. (Unit: 11)
Modern Hubble Diagram
Adding high-redshift supernovae to the Hubble diagram revealed the effects of dark energy. (Unit: 11)
Molecular BEC interference
Interference pattern created by the overlap of two clouds of molecular BECs, each composed of 6Li2 diatomic molecules. (Unit: 6)
Multiwavelength Milky Way
Our galaxy, imaged at many different wavelengths. (Unit: 6)
Muon Decay
The muon's most common decay path. (Unit: 1)
The structure of myoglobin (left) and the form it actually takes in space (right). (Unit: 9)
Natural Selection
Sewall Wright sketched the path different populations might take on the fitness landscape. (Unit: 9)
Neutralized Charges
Neutralized charges in QED and QCD. (Unit: 2)
Neutron Decay
Neutron decay from the inside. (Unit: 2)
Neutron Star Cross-Section
A cross section of a neutron star shows the rich variety of emergent quantum matter expected in its crust and core. (Unit: 8)
Newton's Law of Universal Gravitation
Law of universal gravitation force diagram. (Unit: 3)
NIST F1 Clock
This apparatus houses the NIST F1 cesium fountain clock, which is the primary time and frequency standard of the United States. (Unit: 5)
As this chart shows, not every imaginable nucleus is stable. (Unit: 6)
Optical Lattice
Atoms trapped in an optical lattice. (Unit: 5)
Origin of Particles
All the Standard Model particles could have been produced by the inflaton oscillating around its ground state like a ball rolling around in a valley. (Unit: 4)
Oscillating Model of Helium Atom
A simple classical model fails to explain the stability of the helium atom. (Unit: 6)
Particle in a Box
The first three allowed de Broglie wave modes for a particle in a box. (Unit: 5)
Periodic Table
The periodic table of elements. (Unit: 1)
Photoelectric Effect
When light shines on a metal, electrons pop out. (Unit: 2)
An illustration of two possible regimes of pinning for superfluid vortices in the crust of a neutron star. (Unit: 8)
Pion Decay
Pions play an important role in explaining why atomic nuclei do not split apart. (Unit: 1)
Planck Satellite
The Planck satellite will make precise measurements of fluctuations in the CMB. (Unit: 4)
Prion Structures
Two possible conformations of a prion protein: on the left as a beta sheet; on the right as an alpha helix. (Unit: 9)
Protein Folding Funnel
A schematic of how minimizing the free energy of a molecule could lead to protein folding. (Unit: 9)
Proton Decay
The X boson mediates the decay of the proton. (Unit: 2)
Illustration of the temperature evolution of the Fermi surface in underdoped cuprates. (Unit: 8)
QCD at Different Energies
The QCD coupling depends on energy. (Unit: 2)
QED Coupling
QED at high energies and short distances. (Unit: 2)
Quantum Vortices
Quantum vortices in a BEC (top) and the corresponding phase of the quantum wavefunction (bottom). (Unit: 6)
Quark Flux Tubes
As quarks are pulled apart, eventually new quarks appear. (Unit: 4)
Quark-Gluon Plasma
The aftermath of a heavy ion collision at RHIC, the Relativistic Heavy Ion Collider. (Unit: 4)
Quasars and Gravitational Lenses
Gravitational lensing produces more than one image of distant quasars, as seen in this shot from the Hubble Space Telescope. (Unit: 10)
As shown in the figure, dimensionality can influence dramatically the behavior of quasiparticles in metals. (Unit: 8)
Qubits and Superposition
Quantum computers use qubits. (Unit: 7)
Race Between a Biker and a Light Pulse.
The biker wins the race against the light pulse! (Unit: 7)
Reference Frames
Experimental results remain the same whether they are performed at rest or at a constant velocity. (Unit: 2)
Refractive Index and Transmission
Refractive index variation with the frequency of a probe laser pulse. (Unit: 7)
The circuit diagram (top), bacterial population (center), and plot of the dynamics (bottom) of the repressilator, an example of a simple synthetic biological network. (Unit: 9)
Riemann Surfaces
These objects are Riemann surfaces with genus 0, 1, and 2. (Unit: 4)
The chemical structure of RNA (left), and the form the folded molecule takes (right). (Unit: 9)
Molecules of life: RNA (left) and DNA (right). (Unit: 9)
Rotations in physical space and "particle space." (Unit: 2)
Rutherford's Hydrogen Atom
Rutherford's model of a hydrogen atom. (Unit: 6)
Scattering Cross Sections
Two examples of a scattering cross section. (Unit: 2)
Shell Model for Molecules
Molecules in the Lewis shell picture: the pair bond for H2 and Li2. (Unit: 6)
Short-Distance Gravity Test
Torsion pendulum to test the inverse square law of gravity at sub-millimeter distances. (Unit: 3)
Simulated Higgs Event
Simulation of a Higgs event at the LHC. (Unit: 2)
Simulated LHC Collision
The rules of quantum gravity must predict the probability of different collision fragments forming at the LHC, such as the miniature black hole simulated here. (Unit: 4)
Single-Slit Interference
Ripple tank picture of plane waves incident on a slit that is about two wavelengths wide. (Unit: 5)
SLAC's Evidence for the J/Psi
Computer reconstruction of a psi-prime decay in the SLAC Mark I detector. (Unit: 1)
Density notch soliton. (Unit: 6)
Spacetime in General Relativity
In Einstein's theory of gravity, space is warped but featureless. (Unit: 11)
Spin Pairing in Molecules
Spin pairing in the molecules H2 and Li2. (Unit: 6)
SQUID Amplifiers in the ADMX Detector
SQUID technology boosts the ability of the Axion Dark Matter experiment to detect the faint signals that would indicate the presence of axions. (Unit: 10)
Standard Model
Fundamental particles of the Standard Model. (Unit: 1)
Standard Model
The Standard Model of particle physics. (Unit: 4)
Standing Waves
Standing waves on a string between two fixed endpoints. (Unit: 5)
String Collision
String collisions are softer than particle collisions. (Unit: 4)
String Landscape
Typical string theories or supersymmetric field theories have many candidate scalar field inflatons. (Unit: 4)
String on a Double Torus
Strings can wind around a double torus in many distinct ways. (Unit: 4)
Structure Formation
Small fluctuations in density in the leftmost box collapse into large structures on the right in this computer simulation of the universe. (Unit: 4)
Structure in the Universe
Simulations of structure formation in the universe show the influence of gravity and dark energy. (Unit: 3)
Sunyaev-Zel'dovich Effect
The Sunyaev-Zel'dovich effect allows astronomers to find the signature of galaxy clusters in the CMB. (Unit: 11)
Superconducting SQUID
A Superconducting Qantum Interference Device (SQUID) is the most sensitive type of detector of magnetic fields known to science. (Unit: 8)
Superfluid Vortex
Geometry of a straight vortex line in a superfluid. (Unit: 8)
The fundamental units of matter may be minuscule bits of string. (Unit: 4)
Canceling loops in supersymmetry. (Unit: 2)
Temperature and the de Broglie Wavelength
Atomic de Broglie waves overlap as temperatures are lowered. (Unit: 6)
Temperature Scale
Temperature scale in physics. (Unit: 5)
Temperatures, Energies, and Lengths
Changes in short-distance physics—at the Planck scale—can produce profound changes in cosmology, at the largest imaginable distances. (Unit: 4)
Temperatures, Energies, and Lengths
Energies, sizes, and temperatures in physics, and in nature. (Unit: 2)
Thomson's Experiments
Thomson used the cathode ray tube in three different experiments. (Unit: 1)
Tidal Water Level
Plot of the tidal Water Level (WL) at Port Townsend, Washington. (Unit: 3)
Timeline of the Universe
The history of the universe according to our standard model of cosmology. (Unit: 10)
Timeline of the Universe
Dark energy is now the dominant factor pushing the universe to expand. (Unit: 11)
Torsion Balance to Measure G
Schematic of a torsion balance to measure the gravitational constant, G. (Unit: 3)
Spin flipping on the train. (Unit: 2)
Traveling Salesman Problem
An optimal travelling salesman problem (TSP) tour through Germany's 15 largest cities. It is the shortest among 43,589,145,600 possible tours visiting each city exactly once. (Unit: 9)
Turing Test
Player C is trying to determine which player—A or B—is a computer and which is a human. (Unit: 9)
Twin Paradox
Time dilation/twin "paradox." (Unit: 3)
Two Types of Superconductors
Left: conventional superconductors, and right: heavy-electron superconductors. (Unit: 8)
Two-Wave Interference
Two waves interfere as they cross paths. (Unit: 5)
Type Ia Supernova Spectrum
The spectrum of a Type Ia supernova, shown here, distinguishes it from other supernova types. (Unit: 11)
Underground Neutrino Experiment
Drawing of the underground Brookhaven Solar Neutrino Observatory. (Unit: 1)
Unification of Quarks and Leptons
Quarks and leptons, unified. (Unit: 2)
Uniform Gravitational Field
Equality of gravitational and inertial mass. (Unit: 3)
Unifying the Forces
In the Standard Model (left), the couplings for the strong, weak and electromagnetic forces never meet, while in supersymmetry (right), these forces unify near 1015 GeV. (Unit: 2)
Various Interference Effects
The two-slit interference pattern depends on the distance between the slits. (Unit: 5)
Vela Pulsar
Radiotelescope observations of glitches and postglitch behavior in the Vela pulsar. (Unit: 8)
W Boson Scattering
Scattering of W particles in Feynman diagrams. (Unit: 2)
The electromagnetic force and the constituents of matter. (Unit: 2)
Wavefunction and Probability Distribution
The ground state wavefunction of a harmonic oscillator (left) and the corresponding probability distribution (right). (Unit: 5)
(a)-(d) Some wavefunctions for a particle in a box. Curve (e) is the sum of curves (a-d). (Unit: 5)
Waves on a Circle
If a particle is constrained to move on a circle, its wave must resemble the left drawing rather than the right. (Unit: 4)
Wine Bottle Potential
The wine-bottle potential that is characteristic of spontaneous symmetry breaking. (Unit: 2)
World as a Membrane
The Standard Model particles could be confined to the surface of a membrane, while gravity is free to leak into other dimensions. (Unit: 2)
Z Boson
The Z particle at SLAC. (Unit: 2)