Dark Matter and Dark Energy
Episode 11 of Redefining Reality

Dark Matter and Dark Energy
Show More

Related videos

Matter and Heat
Heat flow into a substance usually raises its temperature. But it can have other effects, including thermal expansion and changes between solid, liquid, and gaseous forms: collectively called phase changes. Investigate these phenomena, starting with an experiment in which Professor Wolfson pours liquid nitrogen onto a balloon filled with air.
Magnetic Energy
Study the phenomenon of self-inductance in a solenoid coil, finding that the magnetic field within the coil is a repository of magnetic energy, analogous to the electric energy stored in a capacitor. Close by comparing the complementary aspects of electricity and magnetism.
Work and Energy
See how the precise definition of work leads to the concept of energy. Then explore how some forces give back the work done against them. These conservative forces lead to the concept of stored potential energy, which can be converted to kinetic energy. From here, develop the important idea of…
Using Energy Conservation
A dramatic demonstration with a bowling ball pendulum shows how conservation of energy is a principle you can depend on. Next, solve problems in complicated motion using conservation of energy as a shortcut. Close by drawing the distinction between energy and power, which are often confused.
Electric Energy
Study stored electric potential energy in fuels such as gasoline, where the molecular bonds represent an enormous amount of energy ready to be released. Also look at a ubiquitous electronic component called the capacitor, which stores an electric charge, and discover that all electric fields represent stored energy.
Space-Time and Mass-Energy
In relativity theory, contrary to popular views, reality is what's not relative: that is, what doesn't depend on one's frame of reference. See how space and time constitute one such pair, merging into a four-dimensional space-time. Mass and energy similarly join, related by Einstein's famous E = mc2.
Energy from the Nucleus
Investigate nuclear fission, in which a heavy, unstable nucleus breaks apart; and nuclear fusion, where light nuclei are joined. In both, the released energy is millions of times greater than the energy from chemical reactions and comes from the conversion of nuclear binding energy to kinetic energy.
Mass and Energy
In this lecture, "classical" physics, as explained by Newtonian and Einsteinian mechanics, provides insight into what makes the Higgs so special. Uncover the key to the Higgs's uniqueness in the particle zoo--that even at its minimum energy state (its "resting" state), the Higgs field has a large, constant value.
Matter, Energy, and Entropy
Episode 1 of The Nature of Matter
Starting with a deck of cards tossed into the air, explore the key concepts of matter, energy, and entropy, which are the building blocks of the physical universe. Study examples of these phenomena, and see how they are demonstrated by the behavior of the airborne cards.
The Nature of Matter - Understanding the Physical World
Discover how the immense variety of matter--stars, mountains, plants, people--is made by a limited number of elements that combine in simple ways. In the engaging lectures of The Nature of Matter, no scientific background is needed to appreciate everyday miracles like a bouncing rubber ball or water's astonishing power to…
The Nature of Light and Matter
Episode 2 of The Nature of Matter
Trace a scientific revolution that started with a curious observation about light and a seemingly nonsensical explanation. Learn how Max Planck's proposal that energy is related to frequency, and Albert Einstein's application of this principle to light, gave birth to modern physics.
A New Theory of Matter
Episode 3 of The Nature of Matter
Discover how the idea that light comes in discrete packets called "quanta" led to a startling new theory of matter: quantum mechanics. One prediction is that matter, like light, behaves as both a particle and a wave, a property observed in subatomic particles such as electrons.