Understanding Time

Electrons are always moving.  They spin very quickly around the nucleus of an atom.  As the electrons zip around, they can move in any direction, as long as they stay in their shell.  Electrons can move in any direction you can imagine.  Electrons are constantly spinning in those atomic shells and those shells, or orbitals, are specific distances from the nucleus.  A guy named Schrödinger started realizing that all electrons weren’t the same and they didn’t move in the same way.  The mathematics describing the vibratory patterns that define the states of atoms in quantum mechanics is identical to that which describes the resonance of musical instruments.  Eventually it was found that all forces in nature can be classified into four types.  The gravitational force holds together the universe at large, plus the atmosphere, water, and us to the planet Earth.  The electromagnetic force governs atomic level phenomena, binding electrons to atoms, and atoms to one another to form molecules and compounds.  The strong nuclear force holds the nucleus together.  The weak nuclear force, is responsible for certain types of nuclear reactions and has little bearing on energy sources today.

In 1905, Albert Einstein published his Special Theory of Relativity, which deals with (frames of reference) objects separating with constant high velocities (close to the speed of light).  In this first theory, Einstein stated that the speed of light was the absolute limit for all velocities and furthermore all observers, whatever their motion, must measure the speed of light to be exactly the same.  Finally, only mass-less objects may attain the speed of light.  This is because as massive objects contract in their direction of motion, their clocks slow down relative to observer’s clocks and they gain mass and thus inertia as they accelerate towards the speed of light.

In order to sidestep the issue of Newton’s Third Law of Motion and the impossibility of matter traveling faster than the speed of light, we can look to Einstein and the relationship between space and time.  Taken together, space, consisting of three dimensions (up-down, left-right, and forward-backward) and time are all part of what’s called the space-time continuum.  In his Special Theory of Relativity, Einstein states two postulates: 1) The speed of light (about 300,000,000 meters per second) is the same for all observers, whether or not they’re moving.  2) Anyone moving at a constant speed should observe the same physical laws.  Putting these two ideas together, Einstein realized that space and time are relative, an object in motion actually experiences time at a slower rate than one at rest.  Although this may seem absurd to us, we travel incredibly slow when compared to the speed of light, so we don’t notice the hands on our watches ticking slower when we’re running or traveling on an airplane.  Scientists have actually proved this phenomenon by sending atomic clocks up with high-speed rocket ships.  They returned to Earth slightly behind the clocks on the ground.

Because space and time are part of the same entity it’s impossible to move in space without moving in time.  Time, for anything moving, changes.  One of the most startling consequences of special relativity is that any moving clock slows down relative to a stationary observer.  There are of course many different types of clocks, such as digital watches, clockwork clocks, atomic clocks and even our own biological clocks, but they are all equally affected by the same principle, namely: moving clocks run slow.  It isn’t until we get to speeds that are a large fraction of the speed of light that any change in the flow of time becomes apparent.  However, at speeds very close to that of light the effect grows in magnitude very rapidly indeed until time almost comes to a standstill.

Written for Reena’s Exploration Challenge #172 – Components of Time.

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