light unable to cross in age of universe

hubble sphere

there are multiple reasons for this (maybe i’m missing some):

1. given the speed of light, in all likelihood (we can’t tell) the diameter of the universe is larger than the distance light can travel in the age of the universe; so that light has yet to reach us, and 

2. given that the universe is expanding (so that all objects appear to be receding at a speed proportional to their distance when observed from any point in the universe), after a certain distance (called the hubble distance, which varies), the rate of expansion of distance is the same as or more than the speed of light: so that that light will NEVER reach us.

http://en.wikipedia.org/wiki/Hubble_sphere

http://en.wikipedia.org/wiki/Observable_universe

the graph of the amount of energy needed to accelerate from rest to a given speed (energy on Y-axis, speed on X-axis) is hyperbolic/asymptotal: the proportions are rather consistent, until you get to relativistic speeds (speeds that are a significant fraction of the speed of light) where the required energy jumps to near infinity in only a small change in speed. because c (the speed of light) is the asymptote, the energy needed to get to it is infinite. one the other side, tachyons (which may or may not exist) share the same traits in reverse: a tachyon requires infinity energy to *DE*celerate to the speed of light, and accelerates as it losses energy.

relativist poetry time!:

there once was a woman named Bright,

who could travel faster than light.

she went out one day,

in a relative way,

and returned on the previous night.

http://en.wikipedia.org/wiki/Tachyon

http://en.wikipedia.org/wiki/Speed_of_light

we usually think of 3 forms of a material deternimed by pressure and temperature: solid, gas, and liquid (and plasma).

yet there are many more, and i read about ones i’ve never heard of all the time.

SOME of the major ones:

Superfluid: exists near absolute zero; flows, but has no viscosity, despite surface tension. will flow up and around containers to form a thin film.

Supersolid: exists near absolute zero; like superfluids, but non-flowing. exibits no friction.

Bose-Einstein Condensate: exists near absolute zero; all component particles/ atoms have the same quantum state and are thus indistingishable in ALL ways.

Quark-Gluon Plasma: matter at such high temperatures that the component atomic particles split into barely associated quarks.

supercritical fluid: high temperature/pressure (but MUCH closer to home than any of the above); were it is impossible to distinguish liquid from gas.

http://en.wikipedia.org/wiki/State_of_matter (links to specific states in article)