Browse Visuals

By Unit:
1. The Basic Building Blocks of Matter
2. The Fundamental Interactions
3. Gravity
4. String Theory and Extra Dimensions
5. The Quantum World
6. Macroscopic Quantum Mechanics
7. Manipulating Light
8. The Challenges of Complexity
9. Biophysics
10. Dark Matter
11. Dark Energy

Visuals: Unit 4

Animations

AdS/CFT: AdS/CFT equates a string theory with gravity to a particle theory without gravity.

Black Holes: One of the strangest predictions of general relativity is that space-time can bend so much that it will produce a hole in the middle of space.

Brane Annihilation: In one model, two branes moving towards each other drove inflation. Their collision ended inflation and resulted in the formation of strings.

Branes: String theory contains more than just strings: it includes multi-dimensional objects, or "branes." Our universe is made up of a 3-dimensional brane.

Extra Dimensions: Above each point in our visible dimensions, a small extra-dimensional space may be hidden.

Fundamental Strings: String Theory proposes that the building blocks of matter are not point like particles, but instead are vibrating "strings."

Gravitational Lensing: Gravitational lensing occurs when a dense object bends space-time and causes the path of a light ray to be deflected around it, producing a distorted image.

Hawking Radiation: According to quantum mechanics, black holes are actually continuously emitting tiny amounts of matter. This is known as Hawking radiation.

Inflation: In its first fraction of a second, our universe expanded by a factor of 10³⁰, growiing by a greater percentage than it has in the 14 billion years since.

String Theory and Extra Dimensions: String theory proposes as many as seven extra spatial dimensions.

Photographs

Cosmic String Lensing: A cosmic string could produce a double image of a galaxy behind it.

Einstein, Albert: Some of Einstein's great insights began in thought experiments.

Kaluza and Klein: Theodor Kaluza (left) and Oskar Klein (right) made a remarkable theoretical description of gravity in a fifth dimension.

Large Hadron Collider: The LHC creates the highest-energy collisions on Earth, but these are irrelevant to Planck-scale physics.

Stability: The weakness of gravity is difficult to maintain in quantum mechanical theory, much as it is difficult to balance a pencil on its tip.

Structure in the Cosmos: While the universe appears approximately uniform, we see varied and beautiful structure on smaller scales.

Graphics

Accreting Black Hole: Artist's conception of a black hole accreting matter from a companion star.

AdS/CFT Duality: The AdS/CFT duality relates a theory on the boundary of a region to a theory with gravity in the interior.

Brane Inflation: A brane and an antibrane moving toward one another and colliding could have caused inflation and the Big Bang.

Branes and Strings: Strings can break open and end on a brane.

Compactified Extra Dimension: String theorists generally believe that extra dimensions are compactified, or curled up.

Cosmic Microwave Background: Map of the temperature variations in the cosmic microwave background measured by the WMAP satellite.

Equivalent String Configurations: The consequences of strings winding around a larger extra dimension are the same as strings moving around a smaller extra dimension.

Expanding Universe: General relativity is consistent with all the cosmological data that characterizes our visible universe.

Expanding Universe: If we run time backwards, the entire universe collapses into a single, infinitely dense point.

Extra-Dimensional Space: A depiction of one of the six-dimensional spaces that seem promising for string compactification.

Gravitational Field Lines: The gravitational field lines spread out radially from a massive particle.

Graviton Exchange: Gravitons arise naturally in string theory, leading to Feynman diagrams like the one on the right.

Gravity and Extra Dimensions: Gravity leaking into extra dimensions could explain the hierarchy problem.

Hawking Radiation: Black holes radiate by a quantum mechanical process.

Horizon Problem: Both sides of the universe look the same, although light could not have traveled from one side to the other.

Inflation: During the period of inflation, the universe grew by a factor of at least 10²⁵.

Inflaton Potential: A potential like the one shown above for the inflaton field could have caused inflation.

Length Scale: Quantum effects meet general relativity somewhere near the center of this length scale.

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.

Planck Satellite: The Planck satellite will make precise measurements of fluctuations in the CMB.

Quark Flux Tubes: As quarks are pulled apart, eventually new quarks appear.

Quark-Gluon Plasma: The aftermath of a heavy ion collision at RHIC, the Relativistic Heavy Ion Collider.

Riemann Surfaces: These objects are Riemann surfaces with genus 0, 1, and 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.

Standard Model: The Standard Model of particle physics.

String Collision: String collisions are softer than particle collisions.

String Landscape: Typical string theories or supersymmetric field theories have many candidate scalar field inflatons.

String on a Double Torus: Strings can wind around a double torus in many distinct ways.

Structure Formation: Small fluctuations in density in the leftmost box collapse into large structures on the right in this computer simulation of the universe.

Superstring: The fundamental units of matter may be minuscule bits of string.

Temperatures, Energies, and Lengths: Changes in short-distance physics—at the Planck scale—can produce profound changes in cosmology, at the largest imaginable distances.

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.