Einstein
introduced a “postulate”, which he defined as “the purport of which
will hereafter be called the ‘Principle of Relativity’”. He went on to add “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 ofsimultaneous 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’.” He
went on further to say: “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”.
From the above, it is clear that he
introduced a “postulate”, which defined time as “time series of events
occurring at different places”, and he evaluated (measured) “the times of
events occurring at places remote from the watch”. Measurement requires a real and absolute unit – otherwise
there cannot be any result of measurement. Thus, the watch must be real and
absolute measure of time. The watch is a mechanical device, which has to real
and subject to mechanical errors. Can such a unit be absolute?
He goes on to add: “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’ tA from A towards B, let it at the ‘B
time’ tB be reflected at B in the direction of A,
and arrive again at A at the ‘A time’ t’A. In accordance
with definition the two clocks synchronize if: tB - tA = t’A - tB)”.
If we go by his postulate that the speed of
light is constant, then tA should be equal to t’A if
the distance between A and B is fixed. If the distance between A and B is
variable, then they will be different. If the variance is random, the two
cannot be correlated as each time we will have a set of different readings. If
the variance follows a fixed patten, then the two times can be correlated and
they would not be relative. Hence ths definition is not free from
contradictions as Einstein assumes.
Einstein further says: “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:
- If the clock at B synchronizes with the clock at A,
the clock at A synchronizes with the clock at B.
- 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”.
What the above statement means is: if both
the watches at A and B synchronize with the watch at C, then the watches at A
and B synchronize. Thus, the watch at C is treated as a fixed reference frame.
Then how can the watches at A and B be relative? If they give reading free of
mechanical error and if the readings are different like seconds and
nano-seconds, then the readings are not relative, but the units are different.
If there is some mechanical error in one of these watches which shows a
different reading, will time become different? Einstein actually uses a
privileged frame of reference to define synchronization and then denies the
existence of any privileged frame of reference. How do you explain this?
Further he adds: “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:
2AB / t’A - tA = c to be
a universal constant - the velocity of light in empty space”.
We have shown above that if the velocity of
light in empty space is
constant, then either t’A = tA or
distance between A and B is variable, in which case they could not be related
simply. If there is a pattern in this variance, we could come to t’A = tA after applying
suitable corrections. If there is no pattern, then t’Acould
not be related to tA. In otherwords, if 2AB = 2 x AB,
then t’A - tA = 0 and c is
infinite. If 2AB = AB +
BA, where AB ≠ BA, then either c = 0 or indeterminate,
according to whether there is a pattern or not. How do you explain this
contradiction?
Assuming time is relative to motion of the
observer, how could we measure it in another frame of reference that is
accelerating with reference to us? Einstein says: “We now inquire as to
the length of the moving rod, and imagine its length to be ascertained by the
following two operations:
(a) The observer
moves together with the given measuring-rod and the rod to be measured, and
measures the length of the rod directly by superposing the measuring-rod, in
just the same way as if all three were at rest.
(b) By means of
stationary clocks set up in the stationary system and synchronizing in
accordance with § 1, the observer ascertains at what points of the stationary
system the two ends of the rod to be measured are located at a definite time.
The distance between these two points, measured by the measuring-rod already
employed, which in this case is at rest, is also a length which may be
designated ‘the length of the rod’.”
The method described at
(b) is misleading. We can do this only by setting up a measuring device
to record the emissions from both ends of the rod at the designated time,
(which is the same as taking a photograph of the moving rod) and then measure
the distance between the two points on the recording device in units of
velocity of light or any other unit. But the picture will not give a correct
reading due to two reasons:
· If
the length of the rod is small or velocity is small, then length contraction
will not be perceptible according to the formula given by Einstein.
· If
the length of the rod is big or velocity is comparable to that of light, then
light from different points of the rod will take different times to reach the
recording device and the picture we get will be distorted due to different
Doppler shift. Thus, there is only one way of measuring the length of the rod
as in (a).
Here also we are
reminded of an anecdote relating to a famous scientist, who once directed two
of his students to precisely measure the wave-length of sodium light. Both
students returned with different results – one resembling the normally accepted
value and the other a different value. Upon enquiry, the other student replied
that he had also come up with the same result as the accepted value, but since
everything including the Earth and the scale on it is moving, for precision
measurement he applied length contraction to the scale treating the star
Betelgeuse as a reference point. This changed the result. The scientist told
him to treat the scale and the object to be measured as moving with the same
velocity and recalculate the wave-length of light again without any reference
to Betelgeuse. After sometime, both the students returned to tell that the
wave-length of sodium light is infinite. To a surprised scientist, they
explained that since the scale is moving with light, its length would shrink to
zero. Hence it will require an infinite number of scales to measure the
wave-length of sodium light!
Some scientists we have
come across try to overcome this difficulty by pointing out that length contraction occurs only in the
direction of motion. They claim that if we hold the rod in a transverse
direction to the direction of motion, then there will be no length contraction.
But we fail to understand how the length can be measured by holding the rod in
a transverse direction. If the light path is also transverse to the direction
of motion, then the terms c+v and c-v vanish
from the equation making the entire theory redundant. If the observer moves together
with the given measuring-rod and the rod to be measured, and measures the
length of the rod directly by superposing the measuring-rod while moving with
it, he will not find any difference because the length contraction, if real,
will be in the same proportion for both.
The fallacy in the
above description is that if one treats “as if all three were at rest”, one
cannot measure velocity or momentum, as the object will be relatively as rest,
which means zero relative velocity. Either Einstein missed this point or he was
clever enough to camouflage this, when, in his 1905 paper, he said: “Now to the
origin of one of the two systems (k) let a constant velocityv be
imparted in the direction of the increasing x of the other
stationary system (K), and let this velocity be communicated to the axes of the
co-ordinates, the relevant measuring-rod, and the clocks”. But is this the velocity of k as measured from
k, or is it the velocity as measured from K? This question is extremely
crucial. K and k each have their own clocks and measuring rods, which are not
treated as equivalent by Mr. Einstein. Therefore, according to his theory, the
velocity will be measured by each differently. In fact, they will measure the
velocity of k differently. But Mr. Einstein does not assign the velocity
specifically to either system. Everyone missed it and all are misled. His spinning
disk example in GR also falls for the same reason.
SPACE,
TIME, DIMENSION: Both space
and time arise from our sense of sequence (priority-posterity) and interval.
When this perception is related to objects, the interval between them is called
space. When it is related to changes in objects, i.e., events, the interval is
called time. We use an easily intelligible and fairly repetitive interval and
subdivide it to get the unit. For space, we use hand or foot measure or some
other standardized interval and for time, we use the day or the year and then
subdivide these to get feet, meter and second, etc. As you can see, the
interval is empty - without a physical existence in the absence of objects and
events. It is imagined through alternative symbolism. Thus, space and time
are really the measurement of intervals, which keeps changing irrespective of
our perception or measurement. Hence both these are fundamental in perceptual
sense. Now we will justify your statement.
Physicists without exception talk about
extra dimensions: 10, 11, 26 or 'n'th dimensions. Dimension is the interface
between the internal structural space and external relational space of objects.
Since we perceive form through electromagnetic interaction, where the electric
field and the magnetic field move perpendicular to each other and both move
perpendicular to their direction of motion, we have three mutually
perpendicular dimensions. In solids, where the 'form' is fixed, these
dimensions are invariant under mutual transformation. You can change length to
breadth or height without disturbing the form. Since time does not fulfil this
criteria, it is not a dimension, though every objects exists in time only.
There is nothing like extra dimensions, which could not be discovered even
after more than a century. Yet, almost all physical theories are based on extra
dimensions.
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