H Physics and Measurement and Philosophy

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What is Physics? I, II, III

The Dancing WuLi Masters
by Gary Zukav

The God Particle (a Flash Reading)
by Leon Lederman
We are not sure about what mass is . . .

   How do the other particles in nature acquire mass?

Research in elementary particle physics is concentrated on the search for a particle called the Higgs Boson. This particle is the missing piece of our present understanding of nature, known as the Standard Model.


What makes kittens so damn cute? Their mass. . .

For over 50 years scientists from across the world have been trying to create an ideal standard mass by producing a solid that consists of a known quantity of identical atoms, and weigh it.

Thanks to the efforts of Russian scientists, such a material is available. It is superpure silicon – pure in the sense that the vast majority of its composition is made up of silicon-28 atoms. As far as other impurities are concerned, including other silicon isotopes, they may be found in proportions not exceeding one atom for every 10 million silicon-28 atoms.

It is superpure silicon, 99.99% comprised of the silicon-28 isotope. There will be 5 kg of such silicon in three years time. This will be sufficient to produce a kilogram sphere, the number of silicon-28 atoms in which will be known precisely. At last the outdated weight held at the Bureau of Weights and Measures in Paris will be replaced by a standard in which not only the mass, but also the number of atoms will be defined to the maximum achievable limit of accuracy for world science today. For the first time scientists the world over will be able to clarify one of the most fundamental chemical values – the Avogadro Constant.

Is length a problem, too?
. . . only if you are going too fast!

The meter is defined as the distance light travels in a vacuum in 1/299,792,458 seconds.

Or, how fast does light travel over a meter?
“The only reason for time is so that everything doesn't happen at once.” Albert Einstein
Time is change --- without change there is no time.
Change requires motion --- no motion no time. I, II, III

by Brian Lemay
Time is measurable if we have a device or natural phenomena that will provide periodic motion. A rotating earth, changing seasons, a swinging pendulum, a tick and a tock all are regular and periodic. These phenomena must be regular enough that we will be able to say with some accuracy when something happened relative to something else. For example; how many swings of the pendulum occured before Nebraska scored a touchdown.
According to the Theory of Relativity, time is not absolute, it is relative. All observers will measure different rates depending on  their relative speeds. Standing still we are all traveling through time at the speed of light. Once we take a step through space, some our speed went into moving through space. Our time slowed down! The faster we move in space the more our time slows.
For a fascinating voyage
Space and Time
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