Perhaps the following extracts can clarify my point of view about “Time”. They are from Posts sent to the internet Google newsgroup “sci.physics” where I participated in some discussions.
First, here
is the meaning of some abbreviations used in these posts that are of common use in the
Usenet newsgroups:
SR = Special
Relativity
GR = General
Relativity
CMBR = Cosmic
Microwave Background Radiation
AFAIK = As far as
I know
SRists =
supporters of Special Relativity
From: (Carlos L)
Newsgroups:
sci.physics,sci.physics.relativity
Subject: Re:
Aspects of time
2004-02-25
LeoK <*@*.chello.se> wrote in message news:<Kme_b.1320$EV2.7257@amstwist00>...
> Hi
>
> Place a super slow hourglass and a atomic clock on our moon
> after synchronizing these with two similar types of clocks
> on our earth.
>
> When reading the changes of the two hourglasses and the
> two atomic clocks. You will find that the hourglass on
> the moon of course is slower than the hourglass on earth.
>
> And the atomic clock on the moon is faster than the
> corresponding atomic clock on earth. (Proof: GPS NAVSTAR.)
> (Indirectly proven.)
>
> Means time according to a hourglass is slower on the moon.
> And time according to a atomic clock is faster on the moon.
> And both types of clocks compared with earth time clocks.
>
> So "my" question is: Is time faster or slower on our moon
> compared to time on earth?
>
> What should Einstein say about these SR/GR effects?
>
> And don't say a hourglass isn't a clock. It is actually a clock.
>
> Does this mean that SR/GR effects only is given by atomic clocks?
> And SR/GR effects can't be showed with hourglasses. Why so, really?
>
> I know that the precision of a hourglass is not the best of clocks,
> but I think we can take the formal question here with this note
> in mind.
>
> What is time really and can we trust in time?
> LeoK
Hi LeoK
Very suggestive your thoughts and questions about 'time'.
Here is *my* point of view:
(Note: I'm trying myself to understand the issue; so forgive me if I
profit the occasion to analyse some details and I result a bit
boring).
First, I agree with you that we must "take the formal question". The
precision of atomic clocks is contingent and is not the fundamental
issue to choose them or not as time standards for the description of
Physics. For example we can imagine a civilization that has developed
a sophisticated technique to extract high time resolution out of
pendulum clocks but doesn't know how to handle atoms to make precise
clocks out of them.
Next, nobody can claim that the rate of ticking of atomic clocks is a
phenomenon *completely* understood for which all possible physical
influences are known (and can be accounted/corrected for). For example
it can not be ascertained that 'when two identical atomic clocks (at
rest relative to each other and under identical gravitation conditions
but not too close in space to one another) are synchronized and
checked to remain so during a small time interval, they will remain
"indefinitely" in sync'. Because we must always admit the possibility
that yet unknown phenomena or uncontrollable physical influences (e.g.
different local vacuum energy?, different showers of neutrinos?,...)
can desynchronise them. (I am of course not referring to the *random*
de-synchronization that is expected to occur due to the accumulation
of quantum fluctuations that would manifest itself macroscopically in
a measurable way after long periods of observation. Such random
de-sync would not be the problem since it could be averaged out).
Therefore there is *in theory* nothing fundamental that imposes the
necessity in Physics to choose atomic clocks as time standards. We
could *in theory* use quartz clocks, spring watches or, why not,
vacuum sealed pendulum clocks or hourglasses to define the time unit
and standard. (Well, of course, under free fall these last clocks
wouldn't work unless we fix a massive basement to them). But these
pendulum or hourglass clocks are not practical not only because they
are not accurate enough for many experiments but because they are too
much affected by known external conditions and/or local conditions
(e.g. by gravitation). But in theory that should not disqualify them
as alternative time standards because we know the precise laws of the
significant phenomena that affect their rate (e.g.
gravity/acceleration, temperature, etc,...) and we could either (1)
correct their readings for those known influences and obtain time
readings that would (except for accuracy) be similar in all
environments to those of atomic clocks, or (2) forget about all
corrections and redefine our physical laws accommodating them to the
new time standard of a pendulum clock and the "relativity of
position". Doing so we would of course obtain very complicated
physical laws for most phenomena, (some sort of epicycles), but we
could build an internally consistent "physics" that makes correct
predictions. Actually quite a few of today's positivist physicists,
that defend that Physics must only be concerned with making good
predictions and not with interpretations, would be delighted to be the
gurus of this new mathematically sophisticated "physics" in which for
example the duration of an Earth's astronomical day would depend on
the position of observation, being significantly shorter (less number
of pendulum periods) if you are on the top of a mountain (with your
clock by your side) instead of at sea level. *For practical purposes*
this is not the case in mainstream Physics that has adopted a time
standard based on caesium clocks that are affected only in a very
small proportion by gravitation gradients as small as those of our
mountains. But strictly speaking, if we give credit to some physicists
that dare pronounce themselves on the subject, it is correct to
interpret the gravitational red shift as a consequence of the "fact"
that atomic clocks run relatively faster on the mountain than at sea
level (or in other words, it could be experimentally proven that our
astronomical day is slightly longer for the mountain observer).
Considering your first question, "Is time faster or slower on our moon
compared to time on earth?" I would answer:
Strictly speaking, your question has no meaning because, for
mainstream Physics, 'time' is only what an official clock (next to you
and at rest) reads. But if we rephrase your question like this: "Is
the duration of all physical phenomena (after correcting for known
physical influences affecting their rate) the same when measured from
the moon as when measured from the earth ? my guess is that *it is
not* due to the influence of gravitation also on atomic clocks as said
above.
Your second question: "Does this mean that SR/GR effects only is given
by atomic clocks? And SR/GR effects can't be showed with hourglasses.
Why so, really?".
Well, since the time variable that enters our physical laws
corresponds by definition to the readings either of official (atomic)
clocks or of other clock mechanisms that have been synchronized with a
standard clock (and known to remain in sync with it under the
pertinent experimental circumstances), then it is trivial that an
hourglass in sync with an official clock will also show the
relativistic effects. If we instead had defined as our time standard
the readings of some other apparatus that are not always (and/or not
everywhere) proportional to the readings of an atomic clock then we
would obtain different expressions for the laws of that "physics" for
which perhaps the word "relativistic" would never had been coined, but
the underlying reality (i.e. its consequences in our world and our
bodies) would of course be the same whether we describe it one way or
another.
And referent to your million $ question: "What is time really and can
we trust in time?" here are my two cents:
First I think that the concept of "time" in Physics needs some
clarification. For me, 'time is an ordering of events'. By "ordering"
I understand creating a list of all the pertinent events of a system
in which a unique number is assigned (or "assignable" at least in
principle, perhaps giving some functions) to every event so that we
can know if its number is bigger or smaller than that of any other
event of the set. We now need a definition of 'event' that is
consistent with such concept of time. My idea of a basic type of event
is: 'a given set of the space positions of *all* the material entities
of the system under consideration in which to each material entity
corresponds only one position'. For example: a set of the positions of
all the elementary particles together with a map of the radiation
(field) that constitute the physical system. (A similarity can be
found with a frame of a movie-film that also contains space-location
information). I also think that it is possible and useful to allow for
different types of events and use the type that adapts better to the
physical description under consideration. For example, an alternative
type of event to be used in other contexts could perhaps be 'a set of
all the temperatures of all the material constituents of a physical
system (i.e. something like a field of temperatures).
It seems important that the concept of "event" that is agreed, does
not contain any connotations related with movement in space or with
physical change because otherwise the definition would be circular
since the concept of 'time' that we are trying to define is itself a
concept that pretends to describe change and movement. But I see no
problem, in theory, to remove from the concept of event any
association with change since it is just a matter of increasing our
number of "film frames" until we are satisfied that all the pertinent
information of our system is included in static frames (e.g. if there
is some information related with change in what we intend to single
out as a *single event*, we just "divide" that multi-pseudo-event in
two or more actual events, and so on).
In this scenario it must be clear that 'no two events have the same
associated number and therefore no two events can be called
simultaneous'. That concept of event is therefore equivalent to the
intuitive concept that we call "instant". Simultaneity is a concept
that must be applied only to sub-events. A "sub-event" can be defined
as 'a given set of the space positions of *some* (but not all) of the
material entities of the system under consideration'. Two sub-events
are simultaneous if they both appear as subsets of the same given
event.
To complete the 'timing' of a physical system and make it operative
for Physics, not only its events must be singled out, but a unique
number must be associated to each event. This is done by adding a
clock to the physical entities that constitute our system and
assigning to each event some characteristic quantity (reading) of the
sub-event "clock" of each event.
The assertion "Time is absolute" made by Newton and assumed explicitly
or intuitively by everybody until the paradigm shift of special
relativity (SR) can here be understood as the belief that any event of
the system "Universe" can be ordered adequately in relation to any
other event in such a way that a consistent description of all the
physical world can be made without violating causality. Causality is
not violated if any physical phenomena (e.g. some information of
contiguous events) can be fully deduced from the knowledge of events
of *only lower order* in the ordered sequence of events.
I myself, and many others, think that "Time is absolute" and that SR
has made a mess of Physics, (but this post is already too long and I'm
tired so I will argue that, when possible, in another post).
Best regards
Carlos L.
From: (Carlos L)
Newsgroups:
sci.physics, sci.physics.relativity
Subject: Re:
Aspects of time
2004-02-28
(Carlos L) wrote in message news:<ac68ac75.0402251939.5b7b92f@posting.google.com>...
> LeoK <*@*.chello.se> wrote in message news:<Kme_b.1320$EV2.7257@amstwist00>...
> > [snip of things already commented in an earlier post]
> > [...]
> > What is time really and can we trust in time?
> > LeoK
Continuing with what I was trying to clarify (mainly to myself) in my
first post in this thread, I am convinced that Physics admits a
consistent description based on "absolute Time". In other words, I
think that all the "reality" of our physical Universe can in principle
be thought as an ordered sequence of events (i.e. some sort of 3D film
frames, each with all the physical entities of the Universe) in such a
way that all observers (whatever their location and/or movement) can
have a local clock that assigns to the events the same number (and
therefore the same order) as do all other observers. That implies
that all observers will agree about which events (or which sub-events)
come first and which after, and about which sub-events are
simultaneous. It is actually that what is meant in general with the
assertion "causality is not violated" (and that is what I want to
subscribe by the moment and not the stronger assertion that I made in
my earlier post).
But even assuming that the physical Universe can be modelled by a "3D
movie-film" (i.e. with absolute time), when we set forth to its
description, we have to face the problem that "we" (its observers)
form part of it and can not just view it "from outside" and simply
proceed to assign increasing numbers to each of the frames (events) of
the 3D movie. Nevertheless, to visualize which kind of clocks must
possess the various observers so that they agree about the timing
(numbering) of the (common by definition) events, it can help to
"imagine" that there actually exists a privileged external observer EO
that has no problems with the description (because he can visualize
all the information in each film-frame and the correct order of the
frames) and guarantees that a consistent description (for all our
local observers) is possible if we are wise enough to set our clocks
to time the events in the right way. (That is just a mental exercise
recommended to some veteran relativists that no longer feel free to
think of Space and Time from the good old conceptual mathematical
point of view but only as measurable quantities of a real observer,
forgetting that a theory is after all a model written in a paper using
well defined mathematical constructs, like Space and Time, that don't
care about SR and can be thought classically).
If the premises of the model are valid (i.e. if a description based on
such concept of absolute Time is possible) then, in principle, to
simplify the problem of synchronization, the best solution would be to
have a *single clock* in the whole physical Universe. That single
clock could be anywhere in space and could have any type of movement
(for the EO it would appear in all the film-frames but not necessarily
always in the same place). The single clock could in principle be any
physical mechanism that outputs in a tape ever increasing rational
numbers. The more numbers per day the better. If the numbers being
output are proportional to some *basic physical quantity* of a basic
phenomenon of nature "measured" automatically by the clock there will
be more chances that the final description (i.e. the laws of Physics)
is simple. (E.g. that "basic" physical quantity could perhaps be the
accumulated number of beats output by *a given* caesium clock, or the
accumulated number of radians of some cyclic adequate astronomical
observation related with the Earth rotation on its axis, etc,...).
The next problem in this scenario of a single Universal clock is to
provide the time readings to any observer whatever his movement and
his place in the "Universe". And this is the delicate point that will
make the description (based on absolute time) succeed or fail. And I
am not referring to the technical difficulties of linking the
Universal clock with signals (e.g. light signals, space ship
messengers, particles, or whatever) to every post of observation, but
to the theoretical problem. The only chance to succeed is to make the
one and only correct prediction about the exact delay that must be
attributed to the signals of each link. That implies *guessing* the
good theories of Physics that describe correctly the velocity of the
pertinent signals in every media that the signals will cross. The "one
way" delay of the signal is the one that has to be correctly deduced
from the theory (Measuring the "two way" delay and dividing it by two
can not be trusted a priori).
Alternately, to provide the time readings to all the observers,
instead of sending signals we could, in the vicinity of the Universal
clock, synchronize other identical clocks with it and then transport
these to the other posts of observation. In this case, the only chance
to succeed with the "Absolute Time description" is to make the good
corrections in the transported clocks to compensate for the physical
perturbations (e.g. speed, gravitational fields,...) that have
affected their basic "mechanism" during their journeys.
The problem in both alternatives is that the exact influences
affecting the signals or the transported clocks must be *guessed* and
implemented into a good operative theory. (The theory need not be a
TOE but a it has to be a correct theory of the pertinent phenomena
related with those signals or clock transports). The *guess* of the
theory will of course be suggested by experimental observations made
with yet non-guaranteed clocks but we must be aware that it can not a
priori be assumed that a physical law describing crude experiments
made with non-guaranteed/non-compensated clocks can directly be as
such incorporated into the sought "correct" theory. It would be
circular reasoning to do that.
Now, my thesis is that SR 'hasn't got right' the issue of
synchronization of relatively moving clocks and is therefore very far
from visualizing the possibility to reincorporate absolute time to
Physics. The wrong track was taken when, to reconcile the experimental
facts (1) light speed is independent is independent of the velocity of
the source, with (2) we measure the same "lab-speed of light" in
vacuum whatever the velocity of our lab relative to the stars, it was
believed that the *only* possible solution was the imaginative theory
(SR) of Einstein in spite of its controversial logic. Unfortunately
some of the predictions made by SR (like those related with the
collision of high speed particles) happened to be much more accurate
than those of Newton's mechanics, and the rest of the story is (also)
well known: an endless 100-year discussion between the defenders of
positivism (SRists) and the defenders of traditional logic and
physical causes. But I am convinced that there is at least another
possible way to reconcile both experimental facts (1) and (2) without
resorting to the "relativity of time": It is always given for granted
that a very brief emission of light once it leaves the emitter
(whether we think of it as a bunch of photons or as a classical
disturbance of the medium) can be characterised as a "body of stuff"
that remains basically together and therefore remains well localized
in space during all its journey to the detector. (I am aware that,
even in vacuum, the mainstream theories actually allow for a
"relatively small" gradual widening of the wave packet due to
statistical indeterminacy considerations, but that is not the widening
that I will refer to). According therefore to mainstream theories if
the supposedly localized light-stuff reaches and triggers a detector
that is at rest in the lab at lab time t, it will happen that, if we
have a second detector moving fast in the lab but passing at time t
next to the first detector, we will observe that it is also triggered
by the light stuff when the lab clock reads t (i.e. at the "3 bodies
space coincidence event" (2 detectors + 1 small "body" of light)).
But then, to account for the constancy of the velocity of light, SR
needs to assume that, in the reference frame of the moving detector, a
clock fixed to this detector, when it passes next to the lab
rest-detector (at the "3 bodies space coincidence event") it will not
show a reading t but a different reading t' (related with t in the
well known ad hoc way such that it can be observed that in both
reference frames the speed of light is c).
If instead (as I have defended many times with no success), it is
assumed: (a) that the light pulse once it leaves the emitter spreads
"completely", like the fragments of an explosion, into bits of a great
plurality of speeds; (b) that each bit (or better, each group of bits
of a given speed) carries with it (i.e. implements in it) at its
specific speed, all the information of the emission (frequency,
polarization, intensity,...), (c) that the physical detectors are only
triggered by "bits" whose speed relative to them is c, then it will
happen that the moving detector is not triggered during the "3 bodies
space coincidence event" but earlier or later (depending of whether it
is moving away or towards the emitter) and it can now be supposed that
the clock of the moving detector is also reading t when it passes
next to the first detector (safeguarding therefore the possibility of
a classical description based on absolute time) . In addition, the
constancy of the velocity of light is also preserved but now it must
be understood as asserting that "the speed of light is always c
relative to the physical detectors, and therefore every inertial
reference frame will measure a speed of light in vacuum equal to c *as
long as its detectors are at rest in such frame*" (I think that it is
only that what the experiments have yet shown. I am not aware that any
light *lab-timing arrival* experiment has been yet made with detectors
of big lab speed).
Best regards
Carlos L.
From:
carlosla@lix.intercom.es (Carlos L)
Newsgroups:
sci.physics,sci.physics.relativity
Subject: Re:
Aspects of time
2004-02-28
"Len Gaasenbeek" <gaasbeek@rideau.net> wrote in message news:<103ssp63mie6r3e@corp.supernews.com>...
> To Carlos,
>
> The problem relativists created is that they contend that when a clock runs
> slow, that the rate at which time flows in the clock's immediate vicinity
> will be slowed down . When you think about it, the two phenomena have
> nothing to do with each other since they do not obey
> "the law of cause and effect", i.e. one doesn't follow from the other.
Interesting thought Len. I agree with you only in part. From one point
of view, I think that the SR logic is internally consistent when it
contends what you say. After all, the SRists believe (1st postulate)
that all the laws of Physics are the same in whatever inertial frame
and therefore when, to account for the constancy of the speed of
light, they assume that the clocks of a moving inertial frame run
slower than ours they must also admit that all their local (to the
"moving" frame) physical processes (e.g. the aging of the travelling
twin, the baking time of their cakes,...) do also run slower according
to our clocks. Otherwise doing the numbers we would conclude that in
the "moving" reference frame they must be finding laws of physics
different from ours.
Parenthesis: The SRists must (and do) admit that it can not in good
logic be just "an appearance" but "a reality" that when our clocks
read 30' the moving cake is insufficiently baked compared to the ones
we also started to bake at the 'synchronization epoch' t = t' = 0.
But according to what most of us expect from Physics, SR has a feeble
point there, because it gives no clue about "why" all the physical
processes of the "moving" frame slow down at the same rate. They at
most say vague things like "the relativity of time is an intrinsic
property of nature that is not the duty of Physics to comprehend.
Physics is concerned with predictions and not with explanations". I
think that the SRists are not completely stupid and they realize that
if they attempt to give *physical* reasons (e.g. of cause and effect)
to explain why the physical processes of the moving frame slow down at
the same rate, they must invoke objective physical properties of space
affecting all the phenomena. They would next have to admit that the
(real) relativistic effects affecting the moving systems are due to
the specific way in which that physical space acts on bodies that move
relative to it. That would be admitting "absolute space" and therefore
they would have to admit that if the clocks of S' go slower than those
of S it must happen that the clocks of S go faster than those of S'
(and not also slower as they pretend to convince us with the peculiar
logic of "relativism"). But then the trick of setting ad hoc the
clocks to explain the constancy of the speed of light would work only
for one moving inertial frame but not for all and so all their card
castle would fall down.
> I recently bought an antique barometer and wanted to adjust it so it showed
> the correct barometric pressure. To this end I went to a store that sold
> barometers to record what they showed the local barometric pressure to be.
> To my dismay I found that no two store barometers showed the same reading.
>
> I concluded from this, not that the barometric pressure was different at
> various locations in the store, but that the store barometers were
> inaccurate.
>
> Since there is no such thing as perfection in this world, it follows that no
> clock will keep perfect time. Consequently, even the best of clocks will
> lose or gain a few seconds in a million years. Next if you shake these
> clocks, change their velocity, temperature, humidity, atmospheric pressure
> (vacuum), atmospheric gas mixture and gravitational field and vibration in
> which they operate, these same clocks will become even less accurate.
Agreed that there are no perfect clocks if by this we mean that 'no
two "identical" physical clocks will keep in sync for ever'.
> The flow of time on the other hand is constant no matter what, since by
> definition we do not allow for short or long seconds. That is to say, a
> second is a second is a second! Not only that, but the flow of time is
> constant and the same throughout the universe, whether there is a person to
> observe it or not.
Hmmm, I don't subscribe those words (although perhaps we are both
defending the same basic idea of "absolute time" except for
secondary-importance attributes). I think that the best meaning that
we can give to "the flow of time" is: 'what a given physical clock
(our standard) reads' In that respect I can agree that it is
"constant". But, as I see it, the important attribute of "absolute
time" is just the possibility to synchronize all the clocks of any
physical system in such a way that any event is assigned the same
number (time) by all the clocks (independently of their location and
state of movement). (By "the same number" we can actually understand
numbers whose spread is less than the error bar of our clocks). But as
long as the numbering (and therefore the order) of the events is the
same for all observers we can change our minds about the most adequate
time standard and change all our previous clocks (that gave a sequence
of numbers t) by another type of clocks that (compared to the first
set) read for example Log[t] instead of t.
> To a child peek-a-boo is reality, not a game. Grown-ups on the other hand
> know,
> that just because you can no longer see a person, that doesn't mean that
> he/she ceased to exist.
>
> Since relativistic physics is built on a fallacy it leads to all kinds of
> silly notions, conclusions and observations. Similarly, you can't count to
> ten if you believe that the number 7 doesn't exist or only exists some of
> the time, no matter how hard you try.
>
> That is why I maintain that relativistic physics is a religion rather than a
> science, because it not only is unscientific and illogical, but also
> because it is based on faith instead of reality.
Agreed. For example the "*relative* time dilation between
relatively-moving clocks" can not be considered to have been
satisfactorily confirmed by experiments. The Hafele-Keating experiment
is very controversial. The Ives & Stilwell experiment can probably be
interpreted as a *real* slow down of the clocks (or atom-oscillations)
when they move at very high speeds relative to the physical space
(aether, vacuum, or whatever name), or more precisely when the
absolute speeds of the emitter and the observer are very different.
> And we all know that you can't argue about a man's faith, because it is
> based on the way he feels rather than reason. (We all have a rational AND
> an emotional half, which cause us to think and behave the way we do.)
>
> Enjoy, Len.
Best regards
Carlos L.
From: (Carlos L)
Newsgroups:
sci.physics,sci.physics.relativity
Subject: Re:
Aspects of time
2004-02-29
glhansen@steel.ucs.indiana.edu (Gregory L. Hansen) wrote in message news:<c1srep$d4g$2@hood.uits.indiana.edu>...
> In article <ac68ac75.0402281512.44d0aeef@posting.google.com>,
> Carlos L <carlosla@lix.intercom.es> wrote:
> >"Len Gaasenbeek" <gaasbeek@rideau.net> wrote in message
> >news:<103ssp63mie6r3e@corp.supernews.com>...
> >But according to what most of us expect from Physics, SR has a feeble
> >point there, because it gives no clue about "why" all the physical
> >processes of the "moving" frame slow down at the same rate. They at
> >most say vague things like "the relativity of time is an intrinsic
> >property of nature that is not the duty of Physics to comprehend.
> >Physics is concerned with predictions and not with explanations".
> > [...]
>
> You seem to think space and time "really" have a Galilean character, and
> that any apparent deviation from that character is something that must be
> explained, while Galileo's invariance of length and universality of time
> under transformations is something to just be accepted as a matter of
> faith, with no explanation needed.
Good points; but probably I didn't express myself clearly and
thoroughly enough and I think that you are misunderstanding me.
I am not sure what you mean by Galilean "character" but: I do not
believe in a Galilean invariance of physical laws (i.e. in Galilean
relativity) because I believe in a preferred reference frame (in which
the aether can be considered at rest), but I do believe in the
Galilean addition of velocities because I believe that a description
based on the "universality of time" (as you call it) is possible. I of
course believe in experiments and particularly in those of collisions
between high speed particles that disprove Newtonian mechanics (at
those speeds). I believe that the properties of space (aether)
determine the behaviour of physical clocks and all other processes
related with change and movement in some (logically) related way. I
admit the possibility that clocks that move relative to the local
aether or that are located in different gravitational potentials
(different aether parameters) get out of sync with those in other
states (of movement and gravitation). Therefore I do not think that
the "universality of time under transformations is something to just
be accepted as a matter of faith, with no explanation needed". What I
believe is that if we make the right compensations for those local
influences in the rate of the pertinent clocks we can obtain a
description based on absolute time (in which all the observers agree
in the order of all the events).
> Have you never wondered why separated
> clocks in different states of motion *should* stay synchronized?
Yes. Their local aether would have the same parameters.
> A *physical* explanation would not be an explanation, but rather a
> recasting of the problem in terms of postulates that you don't feel a need
> to question, and perhaps that it never occurred to you could be
> questioned.
A physical explanation is a description in terms of simpler and more
fundamental postulated laws or/and entities. I don't care about the
"reality" of those basic entities but just about the power and
simplicity of the new description. Science has progressed mainly
thanks to "explanations". (Dalton's atomic theory and (Bernoulli,
Maxwell, Boltzmann,...)'s kinetic theory of gases are within my
favourites).
> But what is the foundation for the assumption of a universal
> time? Experimental? "I don't care what the data looks like, that's just
> the way things are"?
See above.
Best regards.
Carlos L.
Newsgroups:
sci.physics,sci.physics.relativity
Subject: Re:
Aspects of time
2004-03-08
funk420@yahoo.com (luke) wrote in message news:<e1b04639.0403071853.35534eea@posting.google.com>...
Hi Luke:
[...]
>
> Sorry if I repeat an obvious answer someone else may have given but I
> didn't see.. which is, the ratio of the strengths of electromagnetic
> to gravitational forces is HUGE. This is reason enough to prefer the
> electromagnetic (atomic) clock over the gravitational (hourglass), and
> the motivation becomes stronger when you consider which force is at
> work while we think.
>
> In what follows I have replaced the "A" word with "quantum vacuum" for
> PR purposes :)
Ok, and in consideration to your constructive comments I will also
use, in this post, the name "quantum vacuum" instead of the word
"A-----" that gives rise to so many passions and miscommunication.
> > ... I do not
> > believe in a Galilean invariance of physical laws (i.e. in Galilean
> > relativity) because I believe in a preferred reference frame (in which
> > the quantum vacuum can be considered at rest),
>
> I agree.. but this remains speculation. I am optimistic this point
> will be settled in the next decade or so with experiment.
It remains speculation because no experiments are being done today to
try to detect a preferred reference frame (e.g. the one in which the
quantum vacuum can be considered at rest). No experiments are being
done because SR has been so successful making impressive predictions
that, in practice, it is considered unfalsifiable. (Perhaps not only
"in practice" considering that the length standard (meter) was defined
about 20 years ago as the distance travelled in vacuo by light in 0.xx
seconds).
The M-M experiment was a nice attempt to detect a preferred frame but
from my point of view it can exist a preferred frame and nevertheless
not affect the speed of light (that would still be c relative to any
detector). In respect to light, my guess is that it is the intensity
of light rather than its speed the quantity that is affected by
*absolute* motion. (I underlined *absolute* because I am not referring
to the trivial and evident influence of the *relative* velocity
between the source and detector in the intensity of the detected
light. I am rather proposing to measure the intensity received by a
detector of a given velocity relative to the source when both detector
and source are given different velocities relative to the "quantum
vacuum". Probably the effect would be proportional to only 1-(V/c)^2
where I have called V the *absolute* speed of the light source, and
therefore would be very difficult to detect experimentally). But ok,
I'm only speculating and I'm aware that, as long as mainstream Physics
feels comfortable with its present stuff, no one will dare undertake
nor fund any expensive experiment suggested by speculations of SR
opponents. So probably, until an accidental observation happens to
question SR, what we can do is try to make mainstream Physics feel
uncomfortable with its SR-stuff. (That is why I'm often a bit acid and
sarcastic in my posts, trying to be corrosive for SR, but I must add
that I feel the maximum respect for mainstream physicists, for their
knowledge and for their hard and difficult work). To facilitate the
jump from speculations to experiments, it should also help to work (as
I think you are yourself doing) in theories or models that shine some
light on the inconsistencies of SR and/or show that an alternative to
SR is reasonable and possible. I am more optimistic than you and
believe that earlier than "in the next decade or so" experiments will
show that SR must be honourably (why not) placed together with
"Phlogiston" and "Epicycles" in the shelves of the theories that were
once important and useful in the History of Science.
> > but I do believe in the
> > Galilean addition of velocities because I believe that a description
> > based on the "universality of time" (as you call it) is possible. I of
> > course believe in experiments and particularly in those of collisions
> > between high speed particles that disprove Newtonian mechanics (at
> > those speeds). I believe that the properties of space (quantum vacuum)
> > determine the behaviour of physical clocks and all other processes
> > related with change and movement in some (logically) related way.
>
> Yes. e.g. field theory, general relativity.
>
> > I
> > admit the possibility that clocks that move relative to the local
> > quantum vacuum or that are located in different gravitational potentials
> > (different aether parameters) get out of sync with those in other
> > states (of movement and gravitation). Therefore I do not think that
> > the "universality of time under transformations is something to just
> > be accepted as a matter of faith, with no explanation needed". What I
> > believe is that if we make the right compensations for those local
> > influences in the rate of the pertinent clocks we can obtain a
> > description based on absolute time (in which all the observers agree
> > in the order of all the events).
> Ah ha! An excellent suggestion sir.. but how can we determine those
> local properties to make the compensations?
We need a good theory of "quantum vacuum" that describes consistently
the experimental rate-changes suffered by specific types of clocks
(e.g. atomic) when (1) they move (e.g. relative to the CMBR whose
anisotropy gives a good start for an absolute frame) and/or (2) when
they are located in different gravitation fields. GR is not (for me)
the good theory because it rests on SR and because I am convinced that
when "moving clocks change their rate" it is due to *absolute effects*
for which if clock A tics slower than clock B, then, clock B tics
faster than clock A (and not also slower than A, as SR asserts with
insufficient experimental evidence).
> ... And what will be the new
> Greenwich England (a certain quantum vacuum, at a certain epoch of the
> universe, to which we can synchronize our new smart clocks)?
It can be expected that choosing as time standard the rate of a clock
that is at rest relative to the CMBR and in a location of zero net
gravitation forces, "the good theory" of quantum vacuum will give the
simpler recipes for manipulating the clocks of other absolute
velocities and gravitational conditions so that they maintain
synchrony with the first. But in principle any clock of well defined
absolute velocity and gravitation could be chosen as the standard
(just as the Earth was chosen as the standard of absolute rest in the
Ptolemaic description). I agree with you that a reference epoch of the
universe must also be given to nail down the time standard because it
is plausible that the parameters of the "quantum vacuum" (and
therefore some physical "constants") might be slowly changing. But
here I think that any epoch (e.g. 2005 anniversary of SR) can be
chosen with equal rights and expected simplicity.
> We haven't even proved the existence of a dependence on a relative speed
> yet, or explained mass. And of course nobody will be willing to
> abandon the electromagnetic second, its quite nice to be able to tell
> time without knowing your local velocity relative to the quantum
> vacuum or position in a gravitational well.. Such a temporal ordering
> system as you propose will likely only be necessary for future
> technologies.
Agreed, but I would enjoy showing my friends my electromagnetic watch
synchronized to the universal time. The watch, as you suggest, would
have to track both my velocity relative to the quantum vacuum and my
local gravitational parameters. I see some technical problems here:
My absolute velocity should not be (tracked) integrated by inertial
systems that AFAIK would confuse inertial accelerations with
gravitation forces (due to the Equivalence principle of GR). I guess
that it would be good enough to include in my watch an accurate CMBR
analyser. Furthermore my watch's ‘gravitational tracking system'
should not be fouled by my inertial accelerations. But if we trust the
Equivalence Principle of GR, the same corrections would be needed in
my watch whether my acceleration is inertial or gravitational; so no
problem with gravitation, my watch could just include for this a
gyro-laser or an inertial platform. But to be sure that the computer
of my watch makes the adequate corrections (to keep in synch with the
standard) I would prefer to add to it a full ‘quantum vacuum
parameters analyser'.
> I would call it "subtime", and its spatial counterpart
> "subspace".
I would call them "supertime" and "superspace".
> [...]
> > Carlos L.
>
> Thanks again - luke
> http://www.arxiv.org/abs/gr-qc/0304063
[...]
Best regards
Carlos L
From: (Carlos L)
Newsgroups:
sci.physics,sci.physics.relativity
Subject: Re:
Aspects of time
2004-03-11
funk420@yahoo.com (luke) wrote in message news:<e1b04639.0403100821.6022510a@posting.google.com>...
> carlosla@lix.intercom.es (Carlos L) wrote in message news:<ac68ac75.0403082125.256a9397@posting.google.com>...
> > funk420@yahoo.com (luke) wrote in message news:<e1b04639.0403071853.35534eea@posting.google.com>...
> >
> > Hi Luke:
[...]
[Carlos said]:
> > > > ... I do not
> > > > believe in a Galilean invariance of physical laws (i.e. in Galilean
> > > > relativity) because I believe in a preferred reference frame (in which
> > > > the quantum vacuum can be considered at rest),
[Luke said]:
> > > I agree.. but this remains speculation. I am optimistic this point
> > > will be settled in the next decade or so with experiment.
> >
> > It remains speculation because no experiments are being done today to
> > try to detect a preferred reference frame (e.g. the one in which the
> > quantum vacuum can be considered at rest). No experiments are being
> > done because SR has been so successful making impressive predictions
> > that, in practice, it is considered unfalsifiable. (Perhaps not only
> > "in practice" considering that the length standard (meter) was defined
> > about 20 years ago as the distance travelled in vacuo by light in 0.xx
> > seconds).
>
> Perhaps true, however people love to falsify things considered
> unfalsifiable. The difference with relativity is that it is partially
> axiomatic, as you point out. How do you disprove a definition?
>
> > The M-M experiment was a nice attempt to detect a preferred frame but
> > from my point of view it can exist a preferred frame and nevertheless
> > not affect the speed of light (that would still be c relative to any
> > detector).
>
> I agree. So did Michelson and Morley, Lorentz, Fitzgerald, and
> others. With the modern definition of the meter, you are guaranteed
> to measure the speed of light as C. If you don't, it means you made
> an error in calculating the length of your apparatus. This does not
> mean there is no anisotropy of space-time, as you are choosing units
> that would transform it away.
We agree.
[...]
> > But ok,
> > I'm only speculating and I'm aware that, as long as mainstream Physics
> > feels comfortable with its present stuff, no one will dare undertake
> > nor fund any expensive experiment suggested by speculations of SR
> > opponents.
> So who's an SR opponent?
I am (within my limited influence and skills). There are others with
good credentials. e.g. Ronald R. Hatch http://www.egtphysics.net/
> Was Einstein a Newtonian physics opponent?
> Future physical theories will have to reduce to GR/SR under
> appropriate approximations/units..
No, Einstein was not an opened Newtonian-physics opponent. I agree
that most of the times in the history of science the new theory "can
be considered" a generalization of the old one to a wider domain of
applicability. The old theory can still be considered valid in its
limited domain of applicability. But that has not always been so
clearly so. E.g. I would not say that Bohr's theory of the Hydrogen
atom is correct according to the wider range and more successful
quantum mechanics that considers that the electron does not follow
classical orbits. But perhaps we have a semantic issue here that would
lead us nowhere.
[...]
> [...]
>
> We can't assume the local space-time is at rest with respect to the
> CMBR (it isn't). The Earth is not moving through the quantum vacuum
> at 300 km/s (about CMBR rest frame speed), nor is it moving through
> the quantum vacuum at 30 km/s (earth orbital speed).
Perhaps you have here some experimental information about the quantum
vacuum that I'm not aware of. If you assert that so strongly it must
be that there is some really "fundamental" parameter of the quantum
vacuum that is less isotropic in the reference frame of the CMBR than
in some specific frame that I ignore.
> The local
> interstellar cloud, heliospheric magnetic field, and magnetosphere,
> all could represent more local space-time flows.
Hmmm... Perhaps you mean: that there are other stronger disturbances
that contribute more to the anisotropy of our local quantum vacuum
than our movement relative to the CMBR. But if we want to characterize
the essential of the quantum vacuum we must subtract those contingent
(occasional) external influences (e.g. electromagnetic fields) and see
what is left. On the other hand I don't think that the CMBR is an
external contingent influence but is an unavoidable universal and
constant influence characterizing the quantum vacuum. (Actually I
believe more than that: I believe that the CMBR is just the noise of
the aether and not the remnant of a Big Bang; but please forget this
belief that I can not defend at this stage).
[...]
> > I guess
> > that it would be good ... to include in my watch an accurate CMBR
> > analyser.
>
> I don't think that will help much. This will be important for a "mean
> galactic time" or something.
Not only for a mean galactic time. As "explained" above I think that
once the specific external influences (mainly electromagnetic and
gravitational) are removed from the quantum vacuum we are left with a
stuff that will only be isotropic in the frame in which the CMBR can
be considered at rest. It is also my guess that clocks of different
speeds relative to the CMBR will have different ticking rates.
Therefore knowing our speed relative to such CMBR frame will allow us
to correct the clocks for it so that they can keep a good
synchronization with the universal time in which I believe. But its
main interest would be, ok, in outer solar travelling.
> > [...]
> >
> > Very interesting Luke your paper "Spin Waves as Metric in a Kinetic
> > Space-Time" http://www.arxiv.org/abs/gr-qc/0304063 although with my
> > limited knowledge I have only been able to follow the general ideas in
> > it but not the details.
>
> Thanks for reading!
>
> > I have a question somehow suggested by your paper and the discussions
> > of this thread. I am aware that there is an increasing interest in
> > describing the ?vacuum' and its real experimental properties. Your
> > article is a good example. At the same time I find many articles
> > describing the properties of ?space' (or space-time if they prefer)
> > from the point of view of General Relativity. My impression is that
> > both groups of theorists are describing the same stuff (that I
> > call...you know...) but with completely different paradigms and
> > languages. The question would be "is it correct and orthodox to say
> > that GR studies the macroscopic (and cosmological) behaviour of space
> > while quantum vacuum physicists are interested in the microscopic
> > properties of space?"
>
> Sounds good to me!
>
> > [...] Could we draw an analogy between thermodynamics ("GR
> > type" positivistic description) and kinetic statistical theory
> > ("Quantum Vacuum type" description)? Is that one of the things that
> > you are suggesting in your paper?
>
> Yes, that's what I'm suggesting! I'm afraid I don't have most of the
> answers, but I think that paper is a good step forward in that it
> represents a model of light in that framework. It is remarkable how
> much our physics depends on light, in QM and GR. Also there is a
> proposal for a modified version of time dilation that should answer
> your questions about the twin paradox.. at least I am going out on a
> limb enough to make an experimentally verifiable prediction.
>
> You astutely point out "increasing interest" in this area. I have
> been following this closely. A recent cover of scientific american
> said "Atoms of Space" (it was about quantum loop gravity). A recent
> cover of Science et Vie said "Le Vide et Plein D'Energie", about zero
> point energies. It looks to me like these ideas are converging
> quickly, people are tearing down all the walls to come up with a
> consistent theory.
Glad to hear that.
> Keep up the good work everyone!
>
> I have been reading your "EVE model" as well Carlos.
> http://personales.ya.com/carlosla/model/
> I think you are attacking some extremely interesting and important
> problems! ..
> velocity distributions of aetherinos in superspace.. a rather esoteric
> topic is it not?
An elementary (not an esoteric) topic that must be tried. SR is
esoteric. The mathematical sophistications of GR are esoteric.
> Mucho bueno suerte - luke
At least in this point I can certainly correct you: The correct
expression is "Muy buena suerte".
Good luck to you and to your work.
Carlos L
From: (Carlos L)
Newsgroups:
sci.physics,sci.physics.relativity
Subject: Re:
Aspects of time
2004-03-10
greenfield_7@hotmail.com (Jim Greenfield) wrote in message news:<3c4afb26.0403091725.d62a444@posting.google.com>...
> carlosla@lix.intercom.es (Carlos L) wrote in message news:<ac68ac75.0403082125.256a9397@posting.google.com>...
> > funk420@yahoo.com (luke) wrote in message news:<e1b04639.0403071853.35534eea@posting.google.com>...
>
> Sorry to nose in, but who needs a clock to test light speed source
> dependency?
> To see which swimmer is faster, all you need is a pool and a starting
> gun- then see who hits the wall first. Do it to light, and the
> constancy of light will be shown to be a false premise-- and easily
> done!
> From a distant satellite stationary relative to the earth, emit a flash of
> monochromatic light. At that instant have a fast rocket passing close
> to satellite (towards or away from earth), which simultaneously emits
> a flash of same frequency. (use same type of emitter). Compare
> arrivals of flashes- I predict that they will NOT arrive together!
> (distance doesn't need to be known / length of pool)
> (time of light travel doesn't need to be known / just do they hit the
> wall together). I don't even care if we can't tell which flash
> originated where- the fact that the two arrive at different times is
> enough to prove without fear of contradiction, light source
> dependency.
> (the agreement on the simultaneous emissions are by signal between
> rocket and satellite, not from earth, and delays can be tested before
> launch)
But experiments have already been done (confirming the light speed
Source *independency*) where "the distance doesn't need to be known and where
the time of light travel doesn't need to be known". So they are in that
respect equivalent to your proposed experiment.
For example here is the Abstract of an often cited experiment:
------------
"Is the Speed of Light Independent of the Velocity of the Source?",
Phys. Rev. Lett. 39 1051-1054, 1236(E) (1977).
Kenneth Brecher
Department of Physics and Center for Space Research, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139
Recent observations of regularly pulsating x-ray sources in binary
star systems are analysed in the framework of the "emission" theory of
light. Assuming that light emitted by a source moving at velocity v
with respect to an observer has a speed c'=c+kv in the observer's rest
frame, we find that the arrival time of pulses from the binary x-ray
sources implies k<2 x 10-9. This appears to be the most direct and
sensitive demonstration that the speed of light is independent of the
velocity of the source.
------------
> Not a lot of money involved by NASA standards-- will they do it?
Your proposed experiment seems "cheap" as long as the rocket passing
by the satellite uses standard technology but then it would be a very
slow rocket. But many observations (mainly astronomical) have already
confirmed that for those small differences of source speeds no light
speed dependence is observed.
Actually there is no need to chase flies with cannon balls; other type
of experiments can be done and have been done like the famous of
Alvager et al, Physics Letters 12, 260 (1964) that in the lab
"Measured the speed of gamma rays from the decay of fast pi0 (~0.99975
c) to be c with a resolution of 400 parts per million", Well, in this
experiment there are actually measurements of distances and clock
timings involved but AFAIK in a non suspicious and non controversial
way.
> Not a lot of money involved by NASA standards-- will they do it?
> ... Apparently not if those who "depend" upon Relativity theory can avoid
> it!
I don't agree. I think that very few physicists depend in a strong way
on the success of Relativity theory. Perhaps some teachers of the
theory... Instead, a great majority of the professional physicists
that depend on experimental funding should be glad to have good
arguments to start a new series of experiments to revise Relativity.
And if it happened that some experiment falsified Relativity a new
revolution of Physics would begin, bringing funds and interesting work
for everybody (theorists and experimentalists).
But don't misunderstand me Jim. We are somehow in the same submarine
(trying to torpedo SR) because although I do trust the evidence that
the velocity of the source does not affect the speed of light relative
to the observer, I instead believe that the velocity of the *detector*
does affect the speed of light relative the observer. As I've said
many times I believe that the speed of light in vacuo is c relative to
the *material detector*. But if the detector is moving relative to the
reference frame of the observer (i.e. to the frame that puts the
clocks and the meter sticks to reference the measurement) then the
observer will assign to light a speed different from c (obtainable
from the detector's velocity by simple Galilean addition of
velocities). And here, I think instead that there is no experimental
evidence discarding this possibility (that would explain many
experimental facts without the need to assume the relativity of
simultaneity, etc...).
Best regards
Carlos L
> Jim G
From: (Carlos L)
Newsgroups:
sci.physics, sci.physics.relativity
Subject: Re:
Aspects of time
2004-03-11
"Franz Heymann" <notfranz.heymann@btopenworld.com> wrote in message news:<c2o4u0$hb2$18@sparta.btinternet.com>...
> "Carlos L" <carlosla@lix.intercom.es> wrote in message
> news:ac68ac75.0403100910.441e7d1c@posting.google.com...
[...]
> > ... because although I do trust the evidence that
> > the velocity of the source does not affect the speed of light relative
> > to the observer, I instead believe that the velocity of the *detector*
> > does affect the speed of light relative the observer.
>
> I am sure you did not mean what you said, because it is self contradictory.
I mean exactly what I said. It is not contradictory once you
understand what I am saying. It is very simple once you recognize that
the "observer" (reference frame with the meter sticks and the clocks
at rest in it) is not synonymous of the "detector" (physical apparatus
that is triggered by light). You have actually understood it perfectly
when in defence of SR you argue:
> Measuring the speed of light *relative to the observer* means that the
> observer has a detector in his own hands with which to measure the speed of
> light. By definition, then, the speed of the detector *has* to be zero with
> respect to the observer. So what exactly is this moving detector measuring?
> Surely the speed of light relative to *it*. And then it is once again a
> measurement relative to a stationary observer, namely an observer sitting on
> this moving detector.
So please answer me this:
Suppose that in a lab we have an emitter E and a detector D. Suppose
for simplicity that at all times E and D are somewhere along the axis
x of the lab. Suppose that D is moving at a very big speed v relative
to the lab in the +x direction. Suppose that the emitter E emits a
short pulse of light when it is (moving or not, it doesn't matter) at
x=0. The lab clock at x=0 reads t=0 when E emits its pulse. Suppose
that the detector is triggered when it is passing the coordinate x=d
and the lab clock at that position reads T.
Question (1): What new definition of speed has recently been
internationally agreed that says that d/T is not the speed of that
light pulse relative to the lab?
Question (2): is d/T = c ?
My answers:
(1) none
(2) d/T = c+v
> You clearly have your knickers in a twist on this issue.
> May I give you some sound advice: Don't ever frame jump. Frame jumping is
> unhealthy. Decide which frame you are going to sit and observe from, and
> hold all your instruments in your hand while doing so. Any other procedure
> is simply courting a logical disaster.
Then, I suggest that we should explicitly add to SR a 3rd postulate
(that is being implicitly used many times hidden under the euphemism
of "no frame jumping"):
"Any experimental arrangement that contradicts any of the two first
postulates is strictly forbidden".
> Franz Heymann
>
> Franz
> > As I've said
> > many times I believe that the speed of light in vacuo is c relative to
> > the *material detector*. But if the detector is moving relative to the
> > reference frame of the observer (i.e. to the frame that puts the
> > clocks and the meter sticks to reference the measurement) then the
> > observer will assign to light a speed different from c (obtainable
> > from the detector's velocity by simple Galilean addition of
> > velocities). And here, I think instead that there is no experimental
> > evidence discarding this possibility (that would explain many
> > experimental facts without the need to assume the relativity of
> > simultaneity, etc...).
> >
> > Best regards
> > Carlos L
> >
Best regards
Carlos L