harhar. physics ALWAYS works.

hey crap.

this blog's empty again.

sry royce sry dd. we admit our wrongs.

so now we have to make up for it.

how?

i think spamming will do the trick.

or perhaps physics.

nvm, u'll get what i mean. read on.

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EINSTEIN'S THEORY OF RELATIVITY

ON THE ELECTRODYNAMICSOF MOVING BODIES

If a material point is at rest relatively to this system of
co-ordinates, its position can be defined relatively thereto by the
employment of rigid standards of measurement and the methods of
Euclidean geometry, and can be expressed in Cartesian
co-ordinates.

If we wish to describe the motion of a material point,
we give the values of its co-ordinates as functions of the time.
Now we must bear carefully in mind that a mathematical description
of this kind has no physical meaning unless we are quite clear as
to what we understand by ``time.'' We have to take into account
that all our judgments in which time plays a part are always
judgments of simultaneous events. If, for instance, I say,
``That train arrives here at 7 o'clock,'' I mean something like
this: ``The pointing of the small hand of my watch to 7 and the
arrival of the train are simultaneous events.''³

It might appear possible to overcome all the difficulties
attending the definition of ``time'' by substituting ``the position
of the small hand of my watch'' for ``time.'' And in fact such a
definition is satisfactory when we are concerned with defining a
time exclusively for the place where the watch is located; but it
is no longer satisfactory when we have to connect in time series of
events occurring at different places, or--what comes to the same
thing--to evaluate the times of events occurring at places remote
from the watch.

We might, of course, content ourselves with time values
determined by an observer stationed together with the watch at the
origin of the co-ordinates, and co-ordinating the corresponding
positions of the hands with light signals, given out by every event
to be timed, and reaching him through empty space. But this
co-ordination has the disadvantage that it is not independent of
the standpoint of the observer with the watch or clock, as we know
from experience. We arrive at a much more practical determination
along the following line of thought.

If at the point A of space there is a clock, an observer at A
can determine the time values of events in the immediate proximity
of A by finding the positions of the hands which are simultaneous
with these events. If there is at the point B of space another
clock in all respects resembling the one at A, it is possible for
an observer at B to determine the time values of events in the
immediate neighbourhood of B. But it is not possible without
further assumption to compare, in respect of time, an event at A
with an event at B. We have so far defined only an ``A time'' and a
``B time.'' We have not defined a common ``time'' for A and B, for
the latter cannot be defined at all unless we establish by
definition that the ``time'' required by light to travel from
A to B equals the ``time'' it requires to travel from B to A. Let a
ray of light start at the ``A time''
from A towards B, let it at the ``B time''
be reflected at B in the
direction of A, and arrive again at A at the ``A time''
.

In accordance with definition the two clocks synchronize if

We assume that this definition of synchronism is free from
contradictions, and possible for any number of points; and that the
following relations are universally valid:--

1. If the clock at B synchronizes with the clock at A, the clock
   at A synchronizes with the clock at B.



2. If the clock at A synchronizes with the clock at B and also
   with the clock at C, the clocks at B and C also synchronize with
   each other.

Thus with the help of certain imaginary physical experiments we
have settled what is to be understood by synchronous stationary
clocks located at different places, and have evidently obtained a
definition of ``simultaneous,'' or ``synchronous,'' and of
``time.'' The ``time'' of an event is that which is given
simultaneously with the event by a stationary clock located at the
place of the event, this clock being synchronous, and indeed
synchronous for all time determinations, with a specified
stationary clock.

In agreement with experience we further assume the quantity

to be a universal constant--the velocity of
light in empty space.

It is essential to have time defined by means of stationary
clocks in the stationary system, and the time now defined being
appropriate to the stationary system we call it ``the time of the
stationary system.''

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harhar. so now u believe me. physics always works XD