One-Minute Physics archive. Sandrine Ceurstemont, editor, New Scientist TV What's part of the universe?
You may think of it as incorporating everything that exists - both on Earth and in space - but could it also include the unknown? In this One-Minute Physics episode, film-maker Henry Reich delves into the notion of the universe as described by physics, distinguishing between the whole universe and what's observable. He looks at the three components of the universe that we are sure of and whether mathematics could be included or not. Then there is the concept of parallel universes that could extend our understanding of space. If you enjoyed this post, check out our previous animations, to find out, for example, if space is infinite or why mass has a split personality.
Ever been mesmerised by patterns of light at the bottom of a swimming pool? Time travel in the real world isn't yet possible. MacGregor Campbell, contributor We interact with the concept of mass every day. MacGregor Campbell, consultant. Non-Newtonian Fluid on a Speaker Cone. Nuclear Weapons - basic technology concepts [UNC] A few words about nuclear weapons technology..
Fission weapons Nuclear weapons exploit two principle physical, or more specifically nuclear, properties of certain substances: fission and fusion. Fission is possible in a number of heavy elements, but in weapons it is principally confined to what is termed slow neutron fission in just two particular isotopes: 235U and 239Pu. These are termed fissile, and are the source of energy in atomic weapons. An explosive chain reaction can be started with relatively slight energy input (so-called slow neutrons) in such material. An actual 239Pu ingot, alloyed with gallium for improved physical properties Isotopes are 'varieties' of an element which differ only in their number of neutrons. Typical appearance of a thermonuclear weapon detonation -- from many miles away. *Special techniques were required to record the fleeting moments of a weapon's initial detonation.
Physics - The Free Information Society. Ruben's Tube. Science, Pseudoscience, and Irrationalism. Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay First-time Visitors: Please visit Site Map and Disclaimer.
Use "Back" to return here. What's Here and Not Here, And Why Things on this site generally fit one of the following criteria: They're within my area of technical expertise (earth science, physical sciences, astronomy) They pertain to the general nature of science They pertain to other areas where I have personal experience (military issues) They pertain to topics where blatantly fallacious logic is involved Although there is plenty of pseudoscience related to medical fads, diets, and the paranormal, I don't deal with them much because they are outside my formal training. There are certain things I don't put here because this is a site hosted by a public institution Partisan political positions. "Respect" Every so often I get e-mails from people complaining I don't treat these topics or their believers with respect. They're right. Respect? Anti-Evolutionism. 10 Strange Things About The Universe.
Space The universe can be a very strange place.
While groundbreaking ideas such as quantum theory, relativity and even the Earth going around the Sun might be commonly accepted now, science still continues to show that the universe contains things you might find it difficult to believe, and even more difficult to get your head around. Theoretically, the lowest temperature that can be achieved is absolute zero, exactly ? 273.15°C, where the motion of all particles stops completely. However, you can never actually cool something to this temperature because, in quantum mechanics, every particle has a minimum energy, called “zero-point energy,” which you cannot get below. One of the properties of a negative-energy vacuum is that light actually travels faster in it than it does in a normal vacuum, something that may one day allow people to travel faster than the speed of light in a kind of negative-energy vacuum bubble. Relativity of Simultaneity. Gravity.
Richard Dawkins Demonstrates Laryngeal Nerve of the Giraffe.