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On Wed, 20 May 2009 15:14:53 +0100, "Androcles" <...@Hogwarts.physics
"Uncle Ben" <...@q2g2000vbr.googlegroups.com...
BWAHAHAHAHAHAHA!
As an exercise in group theory, let the binary operator 'o' be such that
c o v = (c+v)/(1+v/c) = c (SR's composition of velocities)
"Inverse element
For each a in G, there exists an element b in G such that a o b = b o a = e,
where e is the identity element."
Ref: http://en.wikipedia.org/wiki/Group_(mathematics)
This does NOT mean
v o c = (c+v)/(1+c/v) =v
The identity for addition is zero, you redneck wanker.
The mathematicians think of Special Relativity as an exercise in utter
fuckin' bullshit and Bonehead Green Jr, redneck of science, as an
utter fuckin' bullshitter!
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On Wed, 20 May 2009 14:00:22 -0400, "G. L. Bradford" <...@insightbb.com
What should be observed to *expand* with [local deceleration] would be the
space-time of the at large [non-local] universe.
What should be observed to *contract* with [local acceleration] would be
the space-time of the at large [non-local] universe.
Nothing is going to travel time without also traveling space (1:1) for
cosmologically constant arrivals at 0. Relatively speaking, expanding or
contracting the distances in the coordinate [systems] of universe: the
distances, the space-time, between point coordinates of the Universe. Losing
one set to the -depths- of the Universe. Reacquiring it or acquiring another
set from the -depths- of the Universe.
Nothing is going to travel (or expand or contract) time without also
traveling (expanding or contracting) space.... Relative time, relative
space, 1:1 space:time = all local arrivals then being at a cosmological
constant of 0.
GLB
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On Wed, 20 May 2009 12:54:11 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 2:07 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
I think that we should agree to disagree now. The appeal to a proper
length of the string under the circumstances of BSP seems to be giving
up.
I find it much more satisfying to observe that if the tail of the
string were not constrained, it would assume a length given by the
Lorentz contraction; and to assert that to reattach the string at its
tail would therefore require stress to the string, so much so that it
breaks. It fits the facts.
I'm sure you would agree with my claimed behavior of the string if it
were not constrained. That could be observed by a fly-by inertial
observer.
But thanks for the discussion.
BTW, I have my own admirer who follows me everywhere just to see what
I am doing. I think I am performing a service to the British public
by keeping him tied to his computer, watching for my posts. Who knows
what trouble he could cause if he circulated among the citizens!
Uncle Ben
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Anonymous Wrote:
Uncle Ben says...
How in the world is it "giving up"? The proper length explanation
is perfectly understandable. I really don't understand what you
are looking for in an explanation. What you want is a description
of the phenomenon in terms of the coordinate system of the launch
frame. But *why* do you care about having a description? Why is that
important to you?
In my opinion, you are greatly overestimating the importance of
coordinates and greatly underestimating the importance of invariants
(quantities that can be calculated in any coordinate system whatsoever).
If you have a coordinate-independent explanation of some phenomenon,
then you automatically have an expla
*Why* do you find that more satisfying? What reason is there for
believing that objects undergo Lorentz contraction when they are
accelerated? You're explaining a simple, physical phenonmenon
(strings break when you stretch them too far) by a much more
complicated, more mysterious phenomenon, Lorentz contraction.
*Why* do accelerated objects undergo Lorentz contraction?
If the string is not constrained, then its proper length
remains equal to its equilibrium length. That seems like a
very simple principle. I don't know why you want to replace
it by anything else; it's intuitively clear already.
--
Daryl McCullough
Ithaca, NY
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On Wed, 20 May 2009 14:00:15 -0700 (PDT), Dono <...@comcast.net
On May 20, 1:36 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
He answered that earlie, he wants to takes us back to the stae of
affairs in 1899, when Lorentz was still ruling.
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On Wed, 20 May 2009 14:15:27 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 4:23 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
I believe such a law because I believe SR, and the law can be deduced
from SR.
You ask elsewhere what my motive is for promulgating such a law. It
is merely because so many people -- the same people who get Bell's
question wrong at first -- believe that the effects of SR are not
real, that they are mere artifacts of measurement.
Like Bell, I find it beneficial as a pedagogue to challenge such
people directly by showing that relativistic effects have real
consequences, such as the breaking of a string. Relativity is not a
matter of illusion, time delay of light propagtion, or the magical
effect of observers doing their thing. Relativity is real. Length is
relative. Duration is relative.
One can, as you suggest, evade such a confrontation by changing
frames. I have won many bets with skeptical colleagues. And the way
I finally persuade them that the string breaks is exactly how you are
presenting the problem here, in terms of facts known to us all about
strings at non-relativistic speeds. I show them that the firing times
of the rockets are not simultaneous in the "final frame" when the
rupture occurs, and they pay up.
I was once on the staff of the Commission on College Physics, and at
lunch or during travel together we would play with problems. I found
that my answers often diagreed with those of my colleagues, but they
tended to blow me off in disbelief and the question was never decided.
I overcame this lack of respect by betting, choosing the size of the
bet as large enough to ensure eventual resolution, but not so big as
to make the money important. I chose to bet 50 cents and that only
when I was completely confident in my answer.
The effect was, after three or four such 50-cent bets, that my
colleagues learned to back down and not bet when I offerred a 50 cent
stake. It solved my problem.
Cheers,
Uncle Ben
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Anonymous Wrote:
Uncle Ben says...
Right. But it's deduced from SR by starting with the assumption that
rigid objects always have the same length, as measured in their
instantaneous rest frame.
--
Daryl McCullough
Ithaca, NY
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On Wed, 20 May 2009 07:56:16 -0700 (PDT), Dono <...@comcast.net
On May 20, 5:37 am, Uncle Ben <...@greenba.com
This was explained to you repeatedly but you still don't get it : the
distance between the rockets increases , so the string gets stretched.
Eventually, it breaks.
This is the foundation of SR. You mean, you just discovered it?
You mean , you don't understand SR? After pretending for so many posts
that you do?
Umm, he wasn't, but I can see your agenda. You should talj with Harald
van Lintel, he is another one that wants to take us back to Lorentz's
theory. Daryl tried to explain to you that Lorentz theory is a theory
with one preferential frame, a frame that no one has managed to
detect.
You don't need Lorentz theory to understand that. You only need to
understand that there are no Born-rigid objects. This was discovered
and explained about 100 years ago. You need to brush up your knowledge
of relativity, grampa.
You need to ask yourself the question: how do you measure the length
of an object that moves wrt you?
You can't apply your rulers to it.
Sure, but for a totally different reason from what you have been
thinking. They shrink because they are not Born-rigid.
Wrong, the reason is that the distance between rockets INCREASES. For
the 5-th time, try to read (and understand) the math:
http://en.wikipedia.org/wiki/Bell_spaceship_paradox#Analysis
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On Wed, 20 May 2009 10:27:52 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 10:56 am, Dono <...@comcast.neta complete misunderstanding of my argument.
You say that the distance between the ships increases, and in a frame
in which at least one of them is comoving at the moment of rupture,
you are quite correct. I have understood that probably since before
you were born. My point is different.
What is the physics that explains why the string breaks when
considered ONLY from the launch frame. In the launch frame, the
distance between the ships does not expand.
Please answer THAT question.
Uncle Ben
Uncle Ben
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On Wed, 20 May 2009 11:18:04 -0700 (PDT), Dono <...@comcast.net
On May 20, 10:27 am, Uncle Ben <...@greenba.com
Start reading at 15.4.3 (you can start earlier, in order to
familiarize yourself with accelerated motion in SR, it is quite
possible that it wasn't taught when you were in college)
http://www.ph.utexas.edu/~gleeson/NotesChapter15.pdf
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On Wed, 20 May 2009 10:52:41 -0700 (PDT), Dono <...@comcast.net
On May 20, 10:27 am, Uncle Ben <...@greenba.com
Then how come that you make so many errors?
You didn't answer any of my points where I criticized you for:
1. Trying to return the theory of relativity to Lorentz 1899.
2. Not understanding the effect of acceleration on non Born-rigid
objects (practically all objects)
I answered that question as well. You missed it. In the launcher frame
you simply need to apply the equations of hyperbolic motion and you
will be getting the same exact result : the rockets spacing increases
with coordinate time and the string gets stretched. No need for the
hocky Lorentz contraction. happy now?
Bzzt, wrong.
I just did. For the second time.
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On Wed, 20 May 2009 11:47:55 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 1:52 pm, Dono <...@comcast.net
I think you will find that your answer violates the homogeniety of
flat space-time.
A given rocket model is advertized as being able to go from a standing
start a distance of one light year in two years, w.r.t. the launch
frame.
The same model of rocket positioned differently but fired at the same
time and in the same direction, in the absence of gravitation, will go
the same distance in the same time, again, w.r.t. the launch frame.
You are aguing that the distance between them w.r.t.the launch frame
increases? Why? Both obey F(t) = dp/dt; only the initial conditions
differ. The motions do not have to be hyperbolic;
F(t) is arbitrary, but it is same function for both rockets.
Uncle Ben
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On Wed, 20 May 2009 12:05:58 -0700 (PDT), Dono <...@comcast.net
On May 20, 11:47 am, Uncle Ben <...@greenba.com
I don't know why you steadfastedly refuse to read the materials and
prefer to post BS instead.
It is time you learned accelerated motion in SR:
http://www.ph.utexas.edu/~gleeson/NotesChapter15.pdf
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On Wed, 20 May 2009 12:10:43 -0700 (PDT), Dono <...@comcast.net
On May 20, 11:47 am, Uncle Ben <...@greenba.com
Accelerated motion is hyperbolic in SR. Please read the class notes,
ok?
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On Wed, 20 May 2009 13:49:46 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 3:10 pm, Dono <...@comcast.net
No, the motion is hyperbolic only for constant acceleration. A rocket
motor can have any arbitrary firing and thrust profile including
pauses. That motion will not be hyperboolic.
Thank you for the lead to Gleeson's book. What I am saying is a
generalization of his equation 15.10 for the coordinates of the top
and bottom rockets under constant acceleration, If you subtract the
two coordinates, you will see that w.r.t. the launch frame the
distance between the ships is h for any t
Yet the string breaks. You have my explanation; what is yours?
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On Wed, 20 May 2009 14:03:54 -0700 (PDT), Dono <...@comcast.net
On May 20, 1:49 pm, Uncle Ben <...@greenba.com
...which is the case for the Bell paradox statement.
Why are you trying to create diversions? (not that it is going to
work)
But this is NOT the description of the problem. Can you be honest for
a minute and admit that you were wrong, learn the class notes and get
on with life?
You are not serious, have you read the explanation?
That you have few ideas but fixed :-)
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On Wed, 20 May 2009 14:08:10 -0700 (PDT), Dono <...@comcast.net
On May 20, 1:49 pm, Uncle Ben <...@greenba.com
Eq (15.12) says that you did not understand a darn thing from the
explanation.
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On Wed, 20 May 2009 17:06:28 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 5:08 pm, Dono <...@comcast.net
We are talking about the distance between the top rocket and the
bottom rocket w.r.t. the launch frame. Eq. 15.10 gives this distance.
It shows that the distance from top rocket to bottom rocket is h for
all t
You call my attention to Eq. 15.12. This equation gives the distance
between the dangling end of the string attached to the top rocket and
the bottom rocket. This distance increases w.r.t. the launch frame,
because the string gets shorter with speed. (See title of this
thread.) It is consistent with my description of things.
But it does not support your claim that the distance between rockets
increases w.r.t. the launch frame. In fact, look at the Minkowski
diagram. If you grant that the asymptotes for both rocket world lines
are parallel, then you can see that the horizontal distance between
the asymptotes is constant and the constant is equal to the horizontal
distance between the hyperbolas. Ergo, the distance between the rocket
ships is, again, constant. It is our old friend h.
Whether it is Eq. 15.10 or the Minkowski diagram, if you are any kind
of competent student, you must grant that the distance between ships
is constant w.r.t. the launch frame. If it were not, it would violate
the homogeneity of space, as well.
Now what was it that I am too senile or stupid to understand?
Uncle Ben
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On Thu, 21 May 2009 01:09:01 +0100, "Androcles" <...@Hogwarts.physics
"Uncle Ben" <...@e23g2000vbe.googlegroups.com...
Now what was it that I am too senile or stupid to understand?
Uncle Ben
Ref:
http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img22.gif
the speed of light from A to B is c-v,
the speed of light from B to A is c+v,
the "time" each way is the same.
Well, you did ask.
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On Wed, 20 May 2009 17:59:42 -0700 (PDT), Dono <...@comcast.net
On May 20, 5:06 pm, Uncle Ben <...@greenba.com
Finally, you are getting it. Since the problem constrains the distance
between the rockets to be constant IN THE LAUNCEHER FRAME and since
the distance between the end of the string and the tip of the traling
rocket INCREASES it follows that the string gets STRETCHED. This is
the correct explanation of the Bell paradox in the launcher frame
using the eqs of hyperbolic motion.
Your crackpot explanation based on Lorentz contraction, no matter how
many bets you won when you were young, doesn't hold. The reason is
that the so-called Lorentz contraction is STRESSLESS, by virtue of
being a measuring artifact. I pointed that to you many posts ago, yet
you persisted.
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On Wed, 20 May 2009 19:01:59 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 8:59 pm, Dono <...@comcast.net
Repeatedly you deny it, but when I point out your error three ways,
you claim that you knew it all the time. That is a character flaw. I
shall not respond to any more of your posts.
Uncle Ben
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On Wed, 20 May 2009 17:18:30 -0800, doug <...@xx.com
This sounds like you are claiming that the distance between the
coordinates representing the positions of the ends of the rockets
is behaving differently than the distance between the coordinates
representing the ends of the string. I hope this is not what
you are claiming.
> Uncle Ben
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On Wed, 20 May 2009 18:57:20 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 9:18 pm, doug <...@xx.com
In the text by Gleeson, he first treats the case that the string is
attached to the "top" rocket but not to the "bottom" rocket.
During acceleration the distance between rockets is constant w.r.t.
the launch frame, (because the only difference in their trajectories
is the initial positions).
But the length of the string is not constant, being accelerated and
unconstrained. "Acceleration shrinks objects."
Uncle Ben
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On Wed, 20 May 2009 19:24:26 -0700 (PDT), Dono <...@comcast.net
On May 20, 6:57 pm, Uncle Ben <...@greenba.com
You are one persistent idiot.
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On Wed, 20 May 2009 19:31:01 -0700 (PDT), Dono <...@comcast.net
On May 20, 6:57 pm, Uncle Ben <...@greenba.com
This is a kinematic problem , dumbo. There is no shrinking due to
acceleration. The "free" end of the string simply follows a different
trajectory than the tip of the trailing rocket (compare eqs (15.11)
and (15.12)). It is staring you right in the face and you still repeat
the same idiotic mantra. The more amusing part is that until I showed
you the course notes, you didn't even know the eqs of hyperbolc
motion.....
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Anonymous Wrote:
Uncle Ben says...
That's not completely accurate. For some objects, it depends
on how it is accelerated. For example, for a lump of soft clay,
if you accelerate it by pulling on the front end, then it gets
*longer*. If you accelerate it by pushing on the rear end, then
it gets shorter (in a way that has nothing to do with Lorentz
contraction).
The rule of thumb that acceleration shrinks objects only applies
to objects that have a characteristic proper length (such that
after small compressions or stretches, they tend to snap back
to their characteristic length).
--
Daryl McCullough
Ithaca, NY
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On Thu, 21 May 2009 05:47:35 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 6:22 am, stev...@yahoo.com (Daryl McCullough)
wrote:
Yes, I agree. Furthermore the object is assumed to be unconstrained.
Ben
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On Thu, 21 May 2009 09:15:02 -0400, jem <...@xxx.xxx
If the word "shrinks" is replaced by "changes the sizes of" then your
statement would be correct for the Lorentz Ether model (LET), but in
Relativity, acceleration doesn't shrink objects any more than moving
farther away from them does.
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On Wed, 20 May 2009 07:28:03 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 9:27 am, stev...@yahoo.com (Daryl McCullough)
wrote:
First, Lorentz may have supposed an absolute velocity, but that part
has not survived. Surely you will agree that changes in velocity are
measureable and physically significant.
Rotation in space-time is not quite the same thing as rotation in
space. And the analogous rotary phenomenon would depend on rotational
velocity, not rotational displacement. So I would expect more
observational evidence to support your analogy. We might be led into
the difficulties raised by Ehrenfest.
So no, I don't believe in your analogy, Daryl, although it is food for
thought.
I believe you do accept that Bell's string breaks, however. Yes?
BTW, Sue seems to think she has a champion in you. Congratulations!
Uncle Ben
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Anonymous Wrote:
Uncle Ben says...
I don't believe that. Each of us thinks that the other is a crackpot.
--
Daryl McCullough
Ithaca, NY
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On Wed, 20 May 2009 10:19:31 -0500, shuba <...@lycos.ScPoAmM
That's quite wrong. The analogous parameter to x/t in a Lorentz
boost would be y/x for a rotation, i.e. the slope of a line,
alternatively expressed as a tangent to an angle.
---Tim Shuba---
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On Wed, 20 May 2009 13:07:49 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 11:19 am, shuba <...@lycos.ScPoAmM
You are correct, Tim. My error.
Ben
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Anonymous Wrote:
Uncle Ben says...
In the same way that a change in the orientation of objects
(through rotation) is measureable and physically significant.
(To get a long piece of lumber through a door, you often
must rotate it first).
No, that's not correct. Velocity in spacetime is akin
to orientation in space. Acceleration in spacetime is
akin to rotation in space.
Here's the more precise analogy. The trajectory of
a point-mass through spacetime is analogous to a
one-dimensional curve in space. The velocity of
the trajectory at a point is given by v = dx/dt.
Analogously, the orientation (also called "slope")
of a curve at a point is given by m = dy/dx.
Acceleration is the second-derivative:
a = (d/dt)^2 x. Nonzero acceleration means that
the velocity changes as you move along the trajectory.
For curves, the analogous quantity is the
second derivative of y with respect to x: (d/dx)^2 x.
If that quantity is nonzero, that means that the slope
changes as you move along the curve.
An extended object (for example, a stick) traveling
through spacetime sweeps out a strip of spacetime:
each endpoint traces a trajectory, and the strip
is the space between the two trajectories.
Analogously, a strip (such as a road, or a carpet)
can be thought of as bounded by two different
curves: the curve describing the left side of the
strip, and the curve describing the right side.
There isn't anything to believe in. For every phenomenon
involving trajectories through spacetime, there is an
analogous phenomenon involving curves through space.
Of course I do. Here's the spatial analogy:
Suppose you draw two circles that are non-cocentric,
but have the same radius. They are identical circles,
but with different centers. For definiteness, let
the circles lie on the x-axis, but their centers have
different x-values. Now, consider a strip of carpet
whose left edge follows the leftmost circle, and whose
right edge follows the rightmost circle. Does this
strip have a constant width? No, of course not.
The carpet strip is shaped like a crescent moon.
It has zero width at one end (the point on the
bottom where the two circles intersect), gets
wider toward the middle, and then has zero
width again at the other end.
How can you make a strip of carpet so that
(A) the left edge of the carpet forms a circle,
and (B) the width is constant? The answer is
that such a strip of carpet is a circular
annulus: the left edge forms a circle, and
the right edge forms a circle with the *same*
center, but a *different* radius.
A circular annulus of carpet is the analogy
of the constantly accelerating rocket. The
left edge of the carpet is analogous to the
trajectory of the rear of the rocket. The
right edge of the carpet is analogous to the
trajectory of the front of the rocket. The
difference in radii for the two edges is
analogous to the difference in acceleration
of the two ends of the rocket.
--
Daryl McCullough
Ithaca, NY
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On Wed, 20 May 2009 10:36:40 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 11:14 am, stev...@yahoo.com (Daryl McCullough)
wrote:
That is a helpful summary of the relation of the x-y plane to the x-t
plane, Daryl. Thank you!
But back to the main point. We agree that the string (in BSP)
breaks. We agree on why it breaks when considered from an inertial
frme in which the string is almost c0omo0ving and almost ready to
break.
My question is, what physics explains the rupture of the string when
analzyzed 9only in the launch frame. Physics should be up to that.
Physics should work in every inertial frame. So why -- in the launch
frfame -- does the string brfeak?
My answer is attwmpted shrinkage due to acce3leration. What is
yours?
Uncle Ben
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Anonymous Wrote:
Uncle Ben says...
I don't understand why this isn't enough of an explanation: "The forces
in the string tend to keep its proper length constant". That same
explanation works in every frame, only it's harder to compute the
proper length in the launch frame.
It seems to me exactly analogous with the case of rotating a long
strip of carpet. How do you predict what the new horizontal extent
of the carpet will be? The answer is that the *proper* width remains
constant under a rotation. Computing the proper width is easiest in
a coordinate system in which the carpet is oriented vertically, but
it can be done in any frame.
The proper length of a string is a physically meaningful quantity.
It can be computed in any frame, although it is easiest to compute
in a frame in which the string is at rest. The physically meaningful
explanation of the behavior of a string under accelerations is best
described as: the forces tend to keep the proper length constant.
Of course. If you have an explanation in one frame,
you can translate to an explanation in another frame.
So of course you can explain any phenomenon in any
frame. The explanation is *simplest* in the rest frame
of the object being described (usually).
Associated with every string is an equilibrium length, which is
the length it has when at rest with no forces are applied.
If the endpoints are pulled in such a way that the proper length
is much longer than the equilibrium length, then the string will
break.
That same explanation works in any frame. The only thing that
varies from frame to frame is how to compute "proper length".
--
Daryl McCullough
Ithaca, NY
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On Wed, 20 May 2009 14:33:31 -0500, shuba <...@lycos.ScPoAmM
I've already given an answer. I'll try again, not that I expect
it to influence your obsession.
The internal stresses (or perhaps I should say strain following
Tom's example) change, and the string breaks when it can no
longer support the stresses. Any string with its proper length
increasing will necessarily have changing stresses. This is true
for non-relativistic and relativistic situations, and in either
case is also true in every frame. If you disagree, tell me which
of the following is false, for any possible inertial frame.
1) A string's increase (or not) in proper length is an invariant
which can be determined by measurements in any frame.
2) A string cannot undergo an increase in proper length without
internal stresses changing.
3) If changing stresses in a string occur in one inertial frame,
some changes in stress must occur in any other inertial frame.
4) Strings break when internal stresses cannot be supported.
---Tim Shuba---
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On Wed, 20 May 2009 13:06:59 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 3:33 pm, shuba <...@lycos.ScPoAmM
I might have worded #1 differently, but I agree with you. But I can
also explain the breakage without appealing to a proper length by
noting that an increase in speed shortens the string if not
constrained. That is just as good a physical law.
Ben
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Anonymous Wrote:
Uncle Ben says...
What reason would you have for believing such a law? It's *not*
because of empirical evidence. We don't have any examples of
objects with measurable size that we can accelerate fast enough
to observe length contraction.
What we have experience with is how things behave nonrelativistically.
(1) We have a string that has an equilibrium length of L when at rest.
(2) We observe that there is a maximum length, L_max such that if the
center of the string is at rest, and the length of the string is
L_max or greater, and the ends are being pulled in opposite directions,
then the string will break.
Observation (2) can be done on Earth.
(3) By the relativity principle, if there is *any* frame in which
the center of the string is at rest, and the length is L_max
or greater, and the two ends are being pulled in opposite directions,
then the string will break.
(4) We can calculate, in the Bell's Spaceship Paradox, the trajectories
of the two ends, and prove that there is a point at which (3) holds
in some frame.
(5) We conclude that the string will break.
So the relativity principle allows to leverage what we know about
strings in nonrelativistic situations, and apply them in relativistic
situations. Your "physical law" is *derivable* from facts about
the nonrelativistic case, together with the relativity principle
and the Lorentz transformations.
--
Daryl McCullough
Ithaca, NY
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On Thu, 21 May 2009 11:04:35 -0500, shuba <...@lycos.ScPoAmM
Not really. Physical laws are fundamentally independent of
choice of coordinates. You will need to have another physical
law that a decrease in speed lengthens objects, and will end up
with different physical explanations for the same situation.
Using invariants dispenses with such questionable reasoning, and
the coordinate transformations of special relativity can be used
to get frame-specific values for physical quantities.
Introducing definitions of shinking and stretching as coordinate
dependent entities doesn't help explain the physics. All it does
is deny the simple explanations that we already have from
non-relativistic physics. If a string is stretched enough, it
breaks. The obvious way to retain that idea relativitstically is
to define shinking and stretching as a change in proper length.
---Tim Shuba---
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On Wed, 20 May 2009 16:15:54 -0500, Tom Roberts <...@sbcglobal.net
When you say "length of the rod", readers will very likely interpret
this as being a property of the rod, because you did not qualify it
further. The only property this can refer to is clearly its proper length.
When you say "length of the rod measured in frame S", that is qualified,
and clearly means something different.
When you say "length of the rod" but mean "length of the rod measured in
frame S", you create a disconnect between how readers interpret your
words and what you actually mean. DON'T DO THAT. In SR, one cannot use a
world like "length" without specifying in which frame one means.
Nope. The use of "length" without qualification is AMBIGUOUS. DON'T DO
THAT. This has nothing whatsoever to do with "the truth of SR", it has
to do with precision in language, and accurate communication -- the
burden is on the writer to craft the words such that readers won't
misinterpret them, and will understand what the writer was trying to say.
Sure. Using a relative concept without specifying which frame you intend
it to be relative to, is just asking to be misinterpreted. DON'T DO THAT.
Sure.
The length of a rod is NOT a law of physics.
Hmmm. The laws of physics are generally expressed as differential
equations. Things like the length of a rod and the frame in which it is
at rest are NOT laws of physics, they are INITIAL CONDITIONS for the
application of the differential equations.
One should not "accept this task". Instead, one should understand the
difference between laws of physics and initial conditions.
Your words are too ambiguous. I repeat: when you discuss some property
OF THE ROD, your wording directly implies that the property does not
depend on anything except the rod. You don't mean that, because YOU mean
"length relative to some frame". Your wording is just asking to be
misinterpreted.
I repeat: "It's length" has not changed, but "it's length w.r.t. S'" has
changed. Common usage of words like "it's length" is so ingrained in
most peoples' minds that your omission of frame for a relative concept
like length is too imprecise for useful discussions.
I would advise you to avoid ambiguous words like "real", and to be more
careful in using words so they express what you want to say, rather than
some loose approximation to your thoughts. One aspect of this is NEVER
using a relative term without specifying the frame to which it is relative.
Just look at what you wrote. It makes no sense for a given object to
have "multiple lengths" -- but having multiple "lengths relative to
frames A,B,C,..." is just fine. What you call "length of the rod" is NOT
actually the length of the rod, but is a complex mixture of properties
of the rod and of the frame in which its length is measured. THIS IS NOT
A PROPERTY OF THE ROD. But your wording, using possessive forms as it
does, directly implies you are discussing a property of the rod. DON'T
INTERMIX CONCEPTS LIKE THAT. The rod does not possess any length other
than its proper length; all the different "lengths" you discuss are NOT
properties of the rod, so you should not use possessive case for them.
In your usage, "length" depends on frame, so it is incumbent on you to
specify which frame you mean, EVERY time.
No. To make the statements you make is TOO AMBIGUOUS and TOO IMPRECISE
to discuss SR. This is a LANGUAGE problem, not a physics problem, but
imprecision in language can generate confusion about the physics.
Indeed, most of the confusions in this newsgroup can be traced to
imprecise wording and/or differences in interpretation of statements and
words.
Hmmm. Note that "the velocity of the rod" has PRECISELY the same
problem, and to avoid misinterpretation one must say "the velocity of
the rod wrt frame S".
This is FAR too loose to have any validity. After all, in your example
above, accelerating the rod LENGTHENED the rod wrt S'.
Bottom line: don't use relative terms without specifying the frame to
which they apply. If you do that, you'll never have the problems you
discuss.
Tom Roberts
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On Wed, 20 May 2009 14:26:41 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 5:15 pm, Tom Roberts <...@sbcglobal.net
Tom, I am exquisitely aware that one must define the reference frame
when mentioning a time or a coordinate or any of the other things that
are relative. I think you must be confusing me with someone else
among the replies and replies to replies.
I am surely not perfect in this regard, but you will find that I use
the abbreviation "w.r.t." many more times than most of the people
posting here. In the BSP, I am forever writing "w.r.t. the launch
frame" and the like, sometimes twice in one sentence.
You are right to insist on this, but I plead less guilty than most.
Ben
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On Wed, 20 May 2009 22:50:55 +0100, "Androcles" <...@Hogwarts.physics
"Uncle Ben" <...@r3g2000vbp.googlegroups.com...
Tom, I am exquisitely aware that one must define the reference frame
when mentioning a time or a coordinate or any of the other things that
are relative. I think you must be confusing me with someone else
among the replies and replies to replies.
I am surely not perfect in this regard, but you will find that I use
the abbreviation "w.r.t." many more times than most of the people
posting here. In the BSP, I am forever writing "w.r.t. the launch
frame" and the like, sometimes twice in one sentence.
You are right to insist on this, but I plead less guilty than most.
Ben
===========================================
If you plead guilty less than most then you plead guilty to being
a complete dork.
Go on, Bonehead, tell us what closing speed is w.r.t!
BWAHAHAHAHA!
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On Wed, 20 May 2009 15:09:28 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 5:15 pm, Tom Roberts <...@sbcglobal.net
Tom, the above is unedited. It is exactly what I wrote in the first
part of my post that you copied, and your part is exactly what you
wrote after me.
You will note that I refer to the length of the rod w.r.t. S and the
length of the rod w.r.t. S', and the other two uses of the word length
are in reference to the language "measured to be".
I have not analyzed the rest of my text, but you lashed out at me
before exhibiting ANY violation of the kind you are concerned about.
I think you owe me an apology.
Ben
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Anonymous Wrote:
On Wed, 20 May 2009 15:09:28 -0700 (PDT), Uncle Ben <...@greenba.com
Give him a break. He's backed a loser all his life and has to live with the
fact that becoming an expert in a load of bullshit is nothing to be proud of.
Any rod can be used to define an absolute spatial interval ...You can call it a
'length' or a 'distance' if you like.
Any perfect (non-compressible) rod can be taken anywhere anyhow and the
absolute distance between its ends will not change.
If an observer tries to measure such a rod, when it is relatively moving, by
comparing it with his own similar rod and he gets a different answer then his
method is flawed.
Nobody with any brains would try to measure the length of something that is
relativey moving at high speed anyway.
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On Thu, 21 May 2009 07:16:17 +0100, "Androcles" <...@Hogwarts.physics
"Henry Wilson, DSc" <...@4ax.com...
BWAHAHAHAHAHA!
Roberts and Green both backed a losing horse all their lives and
now they are flogging it after it's dead!
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On Wed, 20 May 2009 18:55:01 -0800, doug <...@xx.com
This is ralph with the fake degrees talking here. Pretty funny ralph.
Ralph loves to bluster about things he is ignorant of.
>
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On Wed, 20 May 2009 19:05:16 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 10:55 pm, doug <...@xx.com
Yes, Doug, I know.
Cheers,Ben
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Anonymous Wrote:
On Wed, 20 May 2009 19:05:16 -0700 (PDT), Uncle Ben <...@greenba.com
Ben, you all seem to agree that nothing physically happens to a rod as a
consequence of an acceleration.
Does this not mean that its ends are separated by the same amount of space no
matter what happens to it.
If all the rods in the universe define spatial intervals and none of them
changes in any way because of a speed shange, does that not prove that space
itself is absolute.
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On Thu, 21 May 2009 00:49:51 -0700 (PDT), Uncle Ben <...@greenba.com
My thesis is still
Acceleration shrinks objects.
Uncle Ben
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On Thu, 21 May 2009 03:05:44 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 21, 3:49 am, Uncle Ben <...@greenba.com
You have written bogus maths to support your
parlour trick. That isn't a thesis. It isn't anything.
Try... "acceleration rotates molecules"
http://en.wikipedia.org/wiki/Induced_gravity
For that there is some experimental support
instead of mathematical artefacts accessible to a
middle school maths student.
Sue...
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On Thu, 21 May 2009 06:59:30 -0700 (PDT), Dono <...@comcast.net
On May 21, 12:49 am, Uncle Ben <...@greenba.com
Very sad, a guy that started as normal and devolved into a crackpot.
Must be the age.....
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On Thu, 21 May 2009 05:42:18 -0700 (PDT), PD <...@gmail.com
No, it does not mean that.
Nothing physically happens to a rod as a result of an observer's
acceleration, but the rod's kinetic energy seems to magically change.
Does this not mean that the kinetic energy carried by the rod cannot
be altered, by conservation of energy?
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Anonymous Wrote:
On Thu, 21 May 2009 05:42:18 -0700 (PDT), PD <...@gmail.com
Don't show your ignorance again Diaper by informing us all that frame dependent
quantities are frame dependent.
We already know that.
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On Fri, 22 May 2009 05:41:51 -0700 (PDT), PD <...@gmail.com
Yes, even though nothing physically is happening to the rod in those
cases too.
You claim that certain properties (like length) are frame-INdependent,
and the argument you use to support that is that nothing is physically
happening to the rod. But that is true in the case of frame-dependent
properties too.
And so in fact, you've not provided any argument that length should be
one of those frame-independent properties other than Your Royal Fiat.
Which doesn't hold much water in science.
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Anonymous Wrote:
On Fri, 22 May 2009 05:41:51 -0700 (PDT), PD <...@gmail.com
Nor does your complete ignorance about the definition of a 'frame'...
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On Fri, 22 May 2009 15:43:48 -0700 (PDT), PD <...@gmail.com
Well, it's been explained to you many times before.
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On Thu, 21 May 2009 07:33:07 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 9:15 am, jem <...@xxx.xxx
Proof: Consider a rod of length L at rest in frame S.
Accelerate the rod gently in the +x direction to speed 0.1 c w.r.t. S
and then stop.
What is its length now w.r.t. S? 0.95 L.
What caused the shrinkage? Has to be the acceleration. Nothing else
changed!
Your explanation? Please use the physics that applies w.r.t. S; no
LTs. We know in E&M that explanations can differ when referred to
different frames. I ask for the physics that applies in S.
Uncle Ben
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On Thu, 21 May 2009 07:35:12 -0700 (PDT), Dono <...@comcast.net
On May 21, 7:33 am, Uncle Ben <...@greenba.com
Old fart,
Why don't you google "Born-rigid motion"? The answer was given about
70 years ago. Correctly, not by using crackpot stuff.
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Anonymous Wrote:
Uncle Ben says...
I don't think it is clear what it means to talk about "physics
that applies in" this frame or that frame. What does that mean?
There aren't different laws of physics in different frames. What
changes from frame to frame is how situations are described
(in terms of coordinates).
So what does it mean to "use the physics that applies in S"?
--
Daryl McCullough
Ithaca, NY
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On Thu, 21 May 2009 08:00:48 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 10:40 am, stev...@yahoo.com (Daryl McCullough)
wrote:
What it means is best illustrated in the first paragraph of Einstein's
1905 paper "On the Electromagnetics of Moving Bodies." Maxwell's
theory acconts differently for electric currents induced in conductors
moving in a magnetic field vs. currents induced in stationary
conductors near a moving magnet.
Uncle Ben
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Anonymous Wrote:
Uncle Ben says...
The description of the electromagnetic field in terms of
E and B changes when you perform a coordinate change. But
using different coordinate systems is *not* physics applied
in different frames. It doesn't matter what frame you are in,
you can use whatever coordinate system you like. Choosing
a coordinate system in which you are at rest at the origin
is convenient for making measurements, but it's *only*
a convenience. There is no rule saying that you have to
use such coordinates.
Coordinates are not mandated by what frame you happen
to be at rest in. They are a choice made by the person
analyzing the situation.
--
Daryl McCullough
Ithaca, NY
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On Thu, 21 May 2009 09:14:00 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 11:35 am, stev...@yahoo.com (Daryl McCullough)
wrote:
Thank you! I choose frame S (in the response to jem above).
Suppose history had been different. Suppose we knew only the
"transformer principle" in electromagnetic theory, i.e., the induction
of current in a stationary conductor by a changing magnetic field.
How useful it would be to use relativity theory to deduce the
"generator principle", i.e. the induction of current in a moving
conductor moving in a fixed magnetic field! Surely this would be a
contribution to electrical engineering as well as to physics.
I won't claim that the law "acceleration shrinks objects" will prove
useful to anybody, but as a physicist and teacher, I hold that (1) it
is true and (2) recognition of its validity helps to clarify the
nature of motion as informed by the Special Theory of Relativity.
Uncle Ben
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On Thu, 21 May 2009 10:58:29 -0500, Tom Roberts <...@sbcglobal.net
I agree.
But we now know how this confusion arose, and how to resolve it. Maxwell
wrote his equations in terms of E and B, which we now know to be
COMPONENTS of an underlying electromagnetic field two-form. The physics
is properly expressed in terms of this EM two-form F and the current
1-form J (d is the exterior derivative, and * is the Hodge dual):
dF = 0
*d*F = J
These two equations contain all 4 of the vacuum Maxwell's equations,
because F incorporates both E and B. Moreover, these equations are
written in coordinate-independent form, and even remain valid (locally)
in a curved manifold.
Einstein was thus talking about different COMPONENTS of the 2-form, not
really about different physics. Modern theoretical physics does not have
the problem Einstein was discussing in 1905.
I repeat: when you say "acceleration shrinks a rod", your readers will
interpret your words as THE ROD ITSELF has shrunk, which is simply not
true. What has shrunk is a PROJECTION of the rod's length onto a
particular coordinate system. That's quite different from the rod ITSELF
shrinking, which is what your words actually say.
Why don't you say "rotation shrinks rods"??? After all, if
I try to carry this long rod through that narrow doorway, it
fits in some orientations but not others, so in EXACTLY the
same sense you mean, rotating the rod has "shrunk" it. That
is, it is really the PROJECTION of the rod onto the doorway
that matters, not the actual length of the rod; your statement
deals with a PRECISELY similar PROJECTION. It's just that mine
is a familiar scenario, and accelerating a rod to ~c is not
familiar at all.
IOW: Lorentz contraction does not affect the object, it only affects a
specific type of measurement of the object. This contraction is not
intrinsic to the object, it is a RELATIONSHIP between the object and the
measurement procedure used to PROJECT its length onto a specific
coordinate system.
Tom Roberts
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On Fri, 22 May 2009 08:41:45 -0400, jem <...@xxx.xxx
An "explanation" for an experimental result is just a demonstration of
the logic used to deduce that result in some model. However, if
you're going to insist on an "explanation" that doesn't come from the
models that best reproduce your result (i.e. "no LTs") then you're
probably out-of-luck, since AFAIK, the next-best model of the
situation is Newton's.
>> different frames. I ask for the physics that applies in S.
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On Fri, 22 May 2009 06:51:20 -0700 (PDT), Uncle Ben <...@greenba.com
On May 22, 8:41 am, jem <...@xxx.xxxOK, just to make sure we are on the same page at an
elementary level, use any LT you like. Do we agree that the length of
the rod w.r.t. S at speed is shorter than at rest? (Some folks on
this NG do, some do not.)
Ben
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On Fri, 22 May 2009 15:35:46 +0100, "Androcles" <...@Hogwarts.physics
"Uncle Ben" <...@h23g2000vbc.googlegroups.com...
On May 22, 8:41 am, jem <...@xxx.xxxOK, just to make sure we are on the same page at an
elementary level, use any LT you like. Do we agree that the length of
the rod w.r.t. S at speed is shorter than at rest? (Some folks on
this NG do, some do not.)
Ben
+++++++++++++++++++++++++++++++++++++++++++++
BWAHAHAHAHAHAHAHA
Just to make sure we are on the same page at an elementary level,
do we agree that an odd number of angels dance on the head of
a pin? (Some folks on this NG do, some say an even number.)
http://en.wikipedia.org/wiki/How_many_angels_can_stand_on_the_head_of_a_pin%3FI n modern usage, this question serves as a metaphor for wasting timedebating topics of no practical value.[1][2]The question how many angels can dance on the head of a pin? has been usedmany times as a trite dismissal of medieval angelology in particular, ofscholasticism in general, and of particular figures such as Duns Scotus andThomas Aquinas.[3] Another variety of the question is How Many Angels CanSit On The Head Of A Pin?It is still a matter of discussion whether this precise topic has ahistorical foundation, in actual writing or disputation from the EuropeanMiddle Ages. One theory is that it is an early modern fabrication[4], usedto discredit scholastic philosophy at a time when it still played asignificant role in university education. James Franklin has raised thescholarly issue, and mentions that there is a seventeenth century referencein William Chillingworth's Religion of Protestants.[5], where he accusesunnamed scholastics of debating " Whether a Million of Angels may not fitupon a needles point?" This is earlier than a reference in the 1678 The TrueIntellectual System Of The Universe by Ralph Cudworth. H.S. Lang, author ofAristotle's Physics and its Medieval Varieties (1992), says (p. 284): "Thequestion of how many angels can dance on the point of a needle, or the headof a pin, is often attributed to 'late medieval writers' ... In point offact, the question has never been found in this form".The modern version in English (usually a needle, rather than a pin) datesback at least to Richard Baxter. In his 1667 tract "The Reasons of theChristian Religion," Baxter reviews opinions on the materiality of angelsfrom ancient times, concluding "And Schibler with others, maketh thedifference of extension to be this, that Angels can contract their wholesubstance into one part of space, and therefore have not partes extrapartes. Whereupon it is that the Schoolmen have questioned how many Angelsmay fit upon the point of a Needle?" [6]
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On Fri, 22 May 2009 10:44:12 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 21, 9:46 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
============
<< Pseudoscientists invent their own vocabulary
in which many terms lack precise or unambiguous
definitions, and some have no definition at all.
Listeners are often forced to interpret the
statements according to their own preconceptions.
What, for for example, is "biocosmic energy?"
Or a "psychotronic amplification system?"
Pseudoscientists often attempt to imitate the
jargon of scientific and technical fields by
technical. Quack "healers" would be lost without
the term "energy," but their use of the term has
nothing whatsoever to do with the concept of
energy used by physicists. http://www.quackwatch.com/01QuackeryRelatedTopics/pseudo.html
Sue...
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Anonymous Wrote:
Sue... says...
Sue, learn to use your words. You can construct
sentences on your own, can't you, or is the only
way you know how to communicate by copying and
pasting.
"Invariant" has a precise, unambiguous definition,
which you couldn't be bothered to look up.
Let's take the simple case of two-dimensional
Euclidean geometry. Take two points A and B on
the Euclidean plane. A Cartesian coordinate system
can define the relationship between these points
in terms of a pair of numbers:
delta-x = the change in the x coordinate from A to B
delta-y = the change in the y coordinate from A to B
delta-x and delta-y are *not* invariants under coordinate
transformations. Depending on how you set up your x-axis
and your y-axis, you get different values for delta-x and
delta-y. However, the combination
D = square-root((delta-x)^2 + (delta-y)^2)
is invariant under translations and rotations.
That *doesn't* mean that the quantity is time-independent.
A and B might be moving apart, so D might be changing
with time. But D has the same value, regardless of how
you set up your Cartesian coordinate system.
Do you understand that? If not, what is it that
you don't understand? Use your words. You're a big girl.
--
Daryl McCullough
Ithaca, NY
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On Fri, 22 May 2009 11:18:49 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 21, 8:42 pm, Uncle Ben <...@greenba.com===============
<< Pseudoscientists invent their own vocabulary
in which many terms lack precise or unambiguous
definitions, and some have no definition at all.
Listeners are often forced to interpret the
statements according to their own preconceptions.
What, for for example, is "biocosmic energy?"
Or a "psychotronic amplification system?"
Pseudoscientists often attempt to imitate the
jargon of scientific and technical fields by
technical. Quack "healers" would be lost without
the term "energy," but their use of the term has
nothing whatsoever to do with the concept of
energy used by physicists. http://www.quackwatch.com/01QuackeryRelatedTopics/pseudo.html
Sue...
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Anonymous Wrote:
Sue... says...
Sue, the fact that you are ignorant of a term does
not mean that it lacks a precise definition. Surely
you know that? Here's a discussion of covariance
and invariance means:
http://en.wikipedia.org/wiki/Covariance_and_contravariance_of_vectors
Do you consider that page to be pseudoscience? What
is imprecise or ambiguous?
--
Daryl McCullough
Ithaca, NY
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On Fri, 22 May 2009 13:13:15 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 22, 3:14 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
Both special relativity (Lorentz covariance) and general relativity
(general covariance) use covariant basis vectors.
Systems of simultaneous equations are contravariant in the variables.
<< A major potential cause of confusion is
that this duality of covariance/contravariance
intervenes every time discussion of a vector or
tensor quantity is represented by its components.
This causes discussion in the mathematics and
physics literature often apparently to be
using opposite conventions. It is not the
convention that differs, but whether an intrinsic
or component-wise description is the primary way
covariant quantities are thought of as moving or
transforming forwards, while contravariant quantities
transform backwards. This depends on whether one is
using a fixed background—a fact that switches the
point of view. http://en.wikipedia.org/wiki/Covariance_and_contravariance_of_vectors
Indeed, it seems to meet the requirements for pseudoscience.
<< Pseudoscientists invent their own vocabulary
in which many terms lack precise or unambiguous
definitions, and some have no definition at all.
Listeners are often forced to interpret the
statements according to their own preconceptions.
What, for for example, is "biocosmic energy?"
Or a "psychotronic amplification system?"
Pseudoscientists often attempt to imitate the
jargon of scientific and technical fields by
technical. Quack "healers" would be lost without
the term "energy," but their use of the term has
nothing whatsoever to do with the concept of
energy used by physicists. http://www.quackwatch.com/01QuackeryRelatedTopics/pseudo.html
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On Thu, 21 May 2009 09:46:14 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 11:58 am, Tom Roberts <...@sbcglobal.net
I grant everything you say except your objection to plain speech. When
physics is taught to undergraduates, we describe things that happen in
the world when objects move fast. The students don't know the
sophisticated language of "rotation" in Minkowski space.
In ordinary speech, it is true that length is defined relative to a
FofR. There is no reason to evade this language. If later we wish to
describe this from an advanced point of view as a projection, fine!
If we speak more plainly about relativity, maybe there will be fewer
physicists who guess wrong about BSP.
Uncle Ben
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Anonymous Wrote:
Uncle Ben says...
Is that really a consideration? If you ask people to guess at an
answer to a question without actually doing a careful analysis,
they often guess wrong. Even highly educated people guess wrong.
Bell's Spaceship Paradox is an example for relativistic physics,
and the Monty Hall problem is an example for probability theory.
Should it be an important for education to improve the accuracy
of off-the-cuff guesses of the answers to scientific questions?
It's possible that that is a worthy goal, because these off-the-cuff
guesses are often the first "line of defense" in figuring out
what questions are worth spending more time on. The deeper
analysis will presumably give you the correct answer, regardless
of what your initial "guess" was, but you have to know enough
to figure that a deeper analysis is warranted.
Anyway, I don't see how the analysis in terms of proper length
is any worse for an off-the-cuff analysis: (1) The string breaks
if its proper length gets too big. (2) If the length in the
"launch frame" is L, then its proper length is roughly
gamma L. So if gamma gets too big, the string breaks.
Why is that hard? My guess is that the people who got
the wrong answer, and said the string doesn't break,
never thought about facts (1) and (2).
--
Daryl McCullough
Ithaca, NY
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On Thu, 21 May 2009 12:32:07 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 1:03 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
OK, let's accept the proper length proof, although appeal to proper
length implies a LT. Does that make the acceleration theorem wrong,
given that all discusants are on board with the relativity of length,
and no one is so backward as to think one means proper length?
Uncle Ben
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On Thu, 21 May 2009 12:53:17 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 1:03 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
If it were well-known that acceleration shrinks strings, with all the
proper qualifications, nobody wouldd get BSP wrong. It would be
obvious.
Uncle Ben
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On Thu, 21 May 2009 15:25:49 -0500, Tom Roberts <...@sbcglobal.net
And we'd also have the same problem that keeps coming up: "speed
increases an object's mass". That involves an incorrect meaning of "mass
of an object", while yours involves a similarly incorrect meaning of
"length of an object". Both involve confusing an intrinsic property of
an object with a measurement from a moving frame.
Bottom line: such sound bites cannot possibly capture the subtleties of
physics.
Tom Roberts
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On Thu, 21 May 2009 15:58:08 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 4:25 pm, Tom Roberts <...@sbcglobal.net
Neither is "gravity is geometry".
The sound bite is not intended to capture all the subtleties of the
physics. It is to remind one of what one has learned earlier in
extenso.
My view of "length" is incorrect? I don't think so. I use it and I
get correct answers. I remember that it, like velocity, momentum and
energy, is defined relative to a FofR. I do not have to express
myself in terms of
invariants and 4-vectors.
I think the prejudice for dealing only with invariants is a case of
"the best being the enemy of the good." The acknowledged beauty of
the 4-dimensional view so enraptures those of a more mathematical mind
that you do not want to admit that some of us still live and work in a
3-dimensional world and need to relate the results of relativity to
that familiar world. If we are willing to adapt to the new reality of
relativity by allowing that certain things we thought were absolute
turn out to be relative -- such as mass, length and time -- we should
be left in peace to do so.
For example, there no logical problem with mass being relative. I can
adapt to F=dp/dt with p = mv involving a factor of gamma. I will get
correct answers. The preference for avoiding "relativistic mass" is
not logical but esthetic.
Uncle Ben
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On Thu, 21 May 2009 19:11:42 -0500, Tom Roberts <...@sbcglobal.net
Neither do I. But saying "length" when you mean "length of a given
object measured in this frame" is woefully inadequate. The length OF THE
ROD does not change with speed, for the usual meaning of those words.
But what one measures in the inertial frame is indeed a length, it is
just the "length of the rod measured in this frame" -- the shortcut you
advocate is inadequate.
Tom Roberts
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On Thu, 21 May 2009 17:33:40 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 8:11 pm, Tom Roberts <...@sbcglobal.net
We may be close to agreement, close enough that to try to clarify more
would be nit-picking. You say "length of the rod measured in this
frame." I say "the length of the rod w.r.t. this frame" when I'm
speaking carefully.
Thanks for sharing your point of view.
Ben
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On Thu, 21 May 2009 20:17:34 -0500, Tom Roberts <...@sbcglobal.net
That's fine. The problem is when you merely say "length" or "length of
the rod", when you really mean "length of the rod w.r.t. this frame".
But you have other problems in nomenclature, just brought up in a recent
post in this thread -- the difference between invariant and changing.
Tom Roberts
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On Thu, 21 May 2009 12:58:41 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 21, 1:03 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
(1)
<< In relativistic physics, proper length is
an invariant quantity http://en.wikipedia.org/wiki/Proper_distance
(2)
<< In relativistic physics, proper length is
an invariant quantity http://en.wikipedia.org/wiki/Proper_distance
So off-the-cuff, the string's length never
changes so it does not break.
More formally:
http://farside.ph.utexas.edu/teaching/em/lectures/node126.html
The string does not break.
So what we have is two quacks that say the string
breaks but they can't offer any support other than
ruminations about that a theory that Einstein
abandoned.
<< Pseudoscience displays an indifference to facts.
Instead of bothering to consult reference works
or investigating directly, its advocates simply
spout bogus "facts" where needed. These fictions
are often central to the pseudoscientist's
argument and conclusions. Moreover, pseudoscientists
rarely revise. The first edition of a pseudoscience
book is almost always the last, even though the
book remains in print for decades or even centuries.
Even books with obvious mistakes, errors,
and misprints on every page may be reprinted as
is, over and over. Compare this to science
textbooks that see a new edition every few years
because of the rapid accumulation of new facts
and insights. http://www.quackwatch.com/01QuackeryRelatedTopics/pseudo.html
Sue...
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Anonymous Wrote:
Sue... says...
You post quotes, but you have no idea what the
words mean, do you? Here's the definition:
http://en.wikipedia.org/wiki/Lorentz_covariance
"... a scalar (e.g. the space-time interval) remains the same under Lorentz
transformations and is said to be a Lorentz invariant"
Invariant doesn't mean the same for all *time*, it means the
same value in all *coordinate systems*. Proper length can
change with time, you silly. If you stretch a rubber band,
its proper length changes.
The problem with relativity is the complete incompetence of
its detractors. We'll never have a revolution to replace the
hegemony of Einstein unless we get a better crop of dissidents,
who actually know the basics of physics.
--
Daryl McCullough
Ithaca, NY
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On Fri, 22 May 2009 12:35:34 -0700, "K_h" <...@SX729.com
"Daryl McCullough" <...@drn.newsguy.com...
Why do you think the incompetence of relativity's detractors is a problem
with relativity itself and why do you think Einstein's hegemony should be
replaced?
Just curious,
k
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On Fri, 22 May 2009 20:42:54 +0100, "Androcles" <...@Hogwarts.physics
"K_h" <...@giganews.com...
Why are you a fucking idiot and why do you think Einstein's drool
should be retained?
Just curious,
A
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Anonymous Wrote:
K_h says...
I was just joking. (Well, not about the detractors being incompetents).
--
Daryl McCullough
Ithaca, NY
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On Fri, 22 May 2009 13:25:34 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 22, 3:42 pm, stev...@yahoo.com (Daryl McCullough)
wrote:
=========
If you would learn some physics instead of defending
a patent examiner's mathematically absurd
notions about time travel then Einstein's relativity
might have fewer detractors.
As you are trying to explain in another thread...
< Einstein's relativity principle states that:
All inertial frames are totally equivalent
for the performance of all physical experiments.
In other words, it is impossible to perform a physical
experiment which differentiates in any fundamental sense
between different inertial frames. By definition, Newton's
laws of motion take the same form in all inertial frames.
Einstein generalized[1] this result in his special theory of
relativity by asserting that all laws of physics take the
same form in all inertial frames. http://farside.ph.utexas.edu/teaching/em/lectures/node108.html
[1] <<... the four-dimensional space-time continuum
of the theory of relativity, in its most essential
formal properties, shows a pronounced relationship
to the three-dimensional continuum of Euclidean
geometrical space. 1 In order to give due prominence
to this relationship, however, we must replace
the usual time co-ordinate t by an imaginary
magnitude
sqrt(-1)
ct proportional to it. Under these conditions,
the natural laws satisfying the demands of the
(special) theory of relativity assume mathematical
forms, in which the time co-ordinate plays exactly
the same role as the three space co-ordinates. http://www.bartleby.com/173/17.html
http://en.wikipedia.org/wiki/Coordinate_time
<< where epsilon_0 and mu_0 are physical
constants which can be evaluated by performing two
simple experiments which involve measuring the force
of attraction between two fixed charges and two fixed
parallel current carrying wires. According to the
relativity principle, these experiments must yield
the same values for epsilon_0 and mu_0 in all inertial
frames. Thus, the speed of light must be the same
in all inertial frames. http://farside.ph.utexas.edu/teaching/em/lectures/node108.html
Sue...
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On Thu, 21 May 2009 17:42:56 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 3:58 pm, "Sue..." <...@yahoo.com.au
A little knowledge is a dangerous thing.
Under certain circumstances, proper length is an invariant, but not
under the conditions of the BSP.
To take an obvious example, suppose the string were a spring and
suppose that one spaceship takes off before the other one. Is the
proper length of the spring invariant?
If you accept all the things you quote about relativity, you will
agree that what is simultaneous in on frame is not simultaneous in
another. So even though in the launch frame the ships depart
simultaneously, in another frame they do not. This changes the proper
length of the spring. And since all stringss are at least slightly
extensible, this also applies to strings.
Uncle Ben
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On Fri, 22 May 2009 02:27:01 -0400, "G. L. Bradford" <...@insightbb.com
"Uncle Ben" <...@u8g2000yqn.googlegroups.com...
On May 21, 3:58 pm, "Sue..." <...@yahoo.com.au
A little knowledge is a dangerous thing.
Under certain circumstances, proper length is an invariant, but not
under the conditions of the BSP.
To take an obvious example, suppose the string were a spring and
suppose that one spaceship takes off before the other one. Is the
proper length of the spring invariant?
If you accept all the things you quote about relativity, you will
agree that what is simultaneous in on frame is not simultaneous in
another. So even though in the launch frame the ships depart
simultaneously, in another frame they do not. This changes the proper
length of the spring. And since all stringss are at least slightly
extensible, this also applies to strings.
Uncle Ben
==========================
The length of the rod is 2ft. The diameter of the galaxy is 200,000 light
years. I can cross the length of the rod in one step. I can cross the
diameter of the galaxy in the same one step, the step's length and time, as
well. The rod is immediately local to me. The galaxy is most definitely not
local to me (I'm a goodly distance outside and over the span of its disk).
In my ship I crossed both rod and galaxy in the same length and time of step
though.
I could just as well have used the example of being aboard an aircraft at
50,000ft, doing 1000mph over a stretch of ground of Earth as I took
precisely the same step, in precisely the same time, over the length of that
2ft. rod (local frame) and over the vastly longer length of that stretch of
ground (non-local frame).
GLB
==========================
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On Thu, 21 May 2009 20:15:09 -0500, Tom Roberts <...@sbcglobal.net
Not true. The proper length of the string in BSP is indeed invariant at
any given instant. It's just that the length of the string is CHANGING,
because the rockets are moving apart in the rest frame of the center of
the string, at any given instant in that frame.
At any given instant, yes. The notion of "invariant" does not take into
account the CHANGING of an object. For a changing object, the proper
length is indeed invariant, but it is changing.
These are QUITE DIFFERENT concepts, and your confusing them is sad....
Tom Roberts
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On Thu, 21 May 2009 18:29:30 -0700 (PDT), Uncle Ben <...@greenba.com
On May 21, 9:15 pm, Tom Roberts <...@sbcglobal.net
I was using "invariant" the way she was using it.
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On Fri, 22 May 2009 09:11:35 -0500, Tom Roberts <...@sbcglobal.net
If you expect others to read your writing, it's FAR better to use words
correctly, with their usual meanings. Note that physics jargon borrows
ordinary words and gives them special, precise meanings, and I include
that in my advice.
Tom Roberts
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Anonymous Wrote:
Uncle Ben says...
Sue doesn't actually know what "invariant" means. It doesn't
mean the same for all time, it means the same in all coordinate
systems. The proper time on a clock is an invariant, but it
certainly isn't the same for all time.
Sue is a silly goose. She's basically harmless, though.
--
Daryl McCullough
Ithaca, NY
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Anonymous Wrote:
On Thu, 21 May 2009 17:42:56 -0700 (PDT), Uncle Ben <...@greenba.com
Simultaneity is universal and absolute. It is not dependent on the human
sensory system, which relies on the finite travel time of communication.
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On Fri, 22 May 2009 12:30:20 -0700, "K_h" <...@SX729.com
"Henry Wilson, DSc" <...@4ax.com...
No it is not.
k
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On Fri, 22 May 2009 20:40:12 +0100, "Androcles" <...@Hogwarts.physics
"K_h" <...@giganews.com...
Yes it is.
A
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Anonymous Wrote:
On Fri, 22 May 2009 12:30:20 -0700, "K_h" <...@SX729.com
Yes it is.
Wilson's Law states that:
"What humans perceive using light for communication is not a true revelation of
what actually happens".
An 'instantaneous universe' can be simulated by an observer setting up an array
of presynched clocks, which perform all his timing experiments.
In one Dimension, consider a line of such clocks in two relatively moving
frames:
Frame1: C1-C2-C3-C4-C5-C6-C7-C8-C9-------------------etc
Frame2 -
Thus, if two events at C5 and C9 are recorded as being simultaneous in Frame1,
then they will also be found to be simultaneous in frame2 according to its
clocks Ca and Cr. (use fixed pitch fonts)
Note, this true whether or not one wishes to believe Einsten's crap about
clocks clocks running slow in moving frames.
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On Sat, 23 May 2009 16:08:38 -0700, "K_h" <...@SX729.com
"Henry Wilson, DSc" <...@4ax.com...
No it is not. You and Androcles are both wrong about this.
Relativity has been experimentally verified as being true. For example,
time dilation has been observed in many experiments and so it is not `crap'.
k
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On Sat, 23 May 2009 16:31:39 -0800, doug <...@xx.com
You forget that you are talking to Ralph with the fake degrees. Ralph
feels that the universe must be the way he says it is since he has
the fake degrees. Ralph knows nothing but likes to bluster to fill
his otherwise useless existence.
>
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On Sun, 24 May 2009 00:23:30 +0100, "Androcles" <...@Hogwarts.physics
"K_h" <...@giganews.com...
Hey shithead!
quote/
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.
/unquote
-- Albert Fuckwit Einstein.
Simultaneity is universal and absolute.
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On Sat, 23 May 2009 17:57:52 -0700 (PDT), Uncle Ben <...@greenba.com
On May 23, 7:23 pm, "Androcles" <...@Hogwarts.physics
[ ... ]
This from the same sage that assures us that there is a smallest real
number greater than zero.
Caveat lector!
Uncle Ben
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On Sun, 24 May 2009 03:48:54 +0100, "Androcles" <...@Hogwarts.physics
"Uncle Ben" <...@y7g2000yqa.googlegroups.com...
On May 23, 7:23 pm, "Androcles" <...@Hogwarts.physics
[ ... ]
Snipping the holey word of St. Einstein, Queer Uncle Bonehead, redneck of
science?
Such heresy...
quote/
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.
/unquote
-- Albert Fuckwit Einstein.
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Anonymous Wrote:
On Sat, 23 May 2009 16:08:38 -0700, "K_h" <...@SX729.com
It has never been verified. There has never been a believable experiment that
supports Einstein's silly theory.
.....so do you disagree with my above proof that simultaneity is universal or
not?
If so, please tell me how.
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Anonymous Wrote:
Uncle Ben says...
The original Lorentz theory had an aether frame, so velocity
was a physically meaningful quantity, since it was compared
with the aether. So the question is whether the physical
explanation for length contraction still makes sense if
you get rid of the aether frame.
[stuff deleted]
[more stuff deleted]
Let me give the analogous story for rotation, and see if you
agree that it's a physical effect in that case, as well.
The action here takes place on a 2 dimensional plane. Arbitrarily,
we call one axis "horizontal" and one "vertical". Now, suppose
we have a very long rectangular strip of carpet, much longer than it is
wide. It's oriented vertically. Now we measure its horizontal
extent, and we find that it is 2 meters wide.
Now, physically rotate the carpet so that it makes an angle of
30 degrees relative to the vertical. We again measure its horizontal
extent. We find now that it is no longer 2 meters wide but is
4 meters wide (2/sin(30)).
(If it's not clear why the measured horizontal extent increases,
try drawing two parallel lines on a piece of graph paper at an angle
so that the lines are not vertical. If the lines are a distance
L apart, then the *horizontal* distance between the lines will
be L/sin(theta), where theta is the angle that the lines make
with the vertical axis.)
Nothing has been done to the strip of carpet, other than rotating
it. So can we conclude that rotation causes carpets to expand?
Is that a physical effect?
What we could say is that there is a notion of the "proper"
width of a carpet, which is the carpet's horizontal extent
as measured in a coordinate system in which the carpet is
oriented vertically. The proper width of a carpet is not
changed by rotation.
From a certain point of view, the "geometric" view,
the claim "Acceleration shrinks objects"
is analogous to the claim "Rotation expands objects".
Acceleration is mathematically akin to a rotation,
but a rotation in spacetime, rather than just space.
--
Daryl McCullough
Ithaca, NY
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On Wed, 20 May 2009 06:33:20 -0700 (PDT), "Sue..." <...@yahoo.com.au
On May 20, 9:27 am, stev...@yahoo.com (Daryl McCullough)
wrote:
Thank you. :-)
<< the most general transformation between two
inertial frames consists of a Lorentz transformation
in the standard configuration plus a translation
(this includes a translation in time) and a
rotation of the coordinate axes.http://farside.ph.utexas.edu/teaching/em/lectures/node113.html
<< if you know about complex numbers you will
notice that the space part enters as if it were
imaginary
R2 = (ct)2 + (ix)2 + (iy)2 + (iz)2 = (ct)2 + (ir)2
where i^2 = -1 as usual. This turns out to be
the essence of the fabric (or metric) of spacetime
geometry - that space enters in with the imaginary
factor i relative to time. http://www.aoc.nrao.edu/~smyers/courses/astro12/speedoflight.html
Sue...
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On Wed, 20 May 2009 07:15:47 -0700 (PDT), Uncle Ben <...@greenba.com
On May 20, 9:27 am, stev...@yahoo.com (Daryl McCullough)
wrote:
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On Wed, 20 May 2009 15:26:57 +0100, "Androcles" <...@Hogwarts.physics
Oh goody, a kook fight!
"Uncle Ben" <...@g19g2000vbi.googlegroups.com...
On May 20, 9:27 am, stev...@yahoo.com (Daryl McCullough)
wrote:
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On Wed, 20 May 2009 07:59:45 -0700 (PDT), S T R I C H <...@gmail.com
On May 20, 9:27 am, stev...@yahoo.com (Daryl McCullough)
wrote:
Nice analogy. But space<believe that space=time, then when one rotates a so-called space-time
interval in a so-called space-time frame, then the space coordinate
transforms to time and the time coordinate transforms to space. In a
similar string of arguments before, I trounced the relativist monkeys
by asking them to transmute space to time and vie versa. After a lot
of hogwash, in the end, the relativist monkeys were unable to convert
space to time and vice versa, or provide solid evidence that these
transmutations do take place.
So in answer to the Spaceship paradox, the string does not break.
relativistic length contractions and time dilations, if they exist,
are mere artifacts of observation and do not apply to reality. As my
favorite example, a cosmic ray travelling towards me at 0.995c
observes me as time dilated by a factor of 10, but I do not feel the
effects of such time dilation at all--I am not aging 10 times less.
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On Wed, 20 May 2009 08:03:20 -0700 (PDT), S T R I C H <...@gmail.com
On May 20, 9:27 am, stev...@yahoo.com (Daryl McCullough)
wrote:
Nice analogy. But space<believe that space=time, then when one rotates a so-called space-time
interval in a so-called space-time frame, then the space coordinate
transforms to time and the time coordinate transforms to space. In a
similar string of arguments before, I trounced the relativist monkeys
by asking them to transmute space to time and vie versa. After a lot
of hogwash, in the end, the relativist monkeys were unable to convert
space to time and vice versa, or provide solid evidence that these
transmutations do take place.
So in answer to the Spaceship paradox, the string does not break.
Relativistic length contractions and time dilations, if they exist,
are mere artifacts of observation and do not apply to reality. As my
favorite example, a cosmic ray travelling towards me at 0.995c
observes me as time dilated by a factor of 10, but I do not feel the
effects of such time dilation at all--I am not aging 10 times less.
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On Wed, 20 May 2009 09:53:00 -0700 (PDT), Double-A <...@hush.com
On May 20, 8:03 am, S T R I C H <...@gmail.com
But when it hits you, it will do damage much greater than could be
caused by the energy mv^2 because of its relativistic momentum.
Double-A
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On Wed, 20 May 2009 12:43:28 -0700 (PDT), Strich-Reply-To-Idiots <...@gmail.com
On 20 Maj, 12:53, Double-A <...@hush.com
X-rays can kill you. They only carry classical momentum.
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On Wed, 20 May 2009 20:10:46 GMT, Sam Wormley <...@mchsi.com
So can water, but you should be aware that
X-ray photons propagate at c through empty space and have
measurable energy
E = hv
and momentum
p = hv/c = h/λ
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On Wed, 20 May 2009 13:18:57 -0700 (PDT), Strich-Reply-To-Idiots <...@gmail.com
On 20 Maj, 16:10, Sam Wormley <...@mchsi.com
We all know that Sam. What is your point? Photons do not carry so-
called relativistic momentum. Do you see your friendly neighborhood
gamma in that formula Sam?
A particle does not need to carry so-called relativistic momentum to
kill anyone. Standard non-relativistic momentum is enough.
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On Wed, 20 May 2009 20:45:46 GMT, Sam Wormley <...@mchsi.com
Did you think photons propagated at other speeds, Strich?
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On Wed, 20 May 2009 23:10:15 GMT, "Simon" <...@spam.spam
Photons don't carry relativistic momentum? Really? What's the mass of a
photon, Strich? What's the classical formula for momentum, Strich?
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On Wed, 20 May 2009 09:50:37 -0700 (PDT), Benj <...@iwaynet.net
On May 20, 11:03 am, S T R I C H <...@gmail.com
You've actually "trounced" nobody. Just because nobody knows the
technology (in public anyway) of how to rotate time-space to transform
to a situation where space "passes" and you "travel" time doesn't mean
it's impossible. Anyone who says something is "impossible" is really
saying "I'm a moron".
Now this is the KEY factor in relativity. Physics today is so enamored
of mathematics that they all believe that math is more real than
reality. Nonsense. Relativity is all about how things APPEAR to
observers! It is NOT about how things change when they move! Speeding
sticks do not change length as they move, they only appear to
observers to do so. Time is not changing speed it only appears to do
so to relative observers. The difference may seem slight, but
philosophically it is worlds apart. One says the world works by magic.
The other says that the world only appears to us in our position as if
it works by magic. These two things are far from identical.
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On Wed, 20 May 2009 21:18:07 +0300, "Ahmed Ouahi, Architect" <...@welho.com
As a definitely, this is what is all about...
However, as a speed, does not change anything from its an initial form, but
certainly does change its behaviours as it does change its appearence for an
eventual observer...
Therefore, as it means a definitely that it shrinks any object along any
speed, whether would remains depending on a distance among the observer as
what would it add along any vision all along, a definitewly as a matter a
fact...
--
Ahmed Ouahi, Architect
Best Regards!
"Benj" <...@s16g2000vbp.googlegroups.com...
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On Wed, 20 May 2009 12:43:33 -0700 (PDT), Strich-Reply-To-Idiots <...@gmail.com
On 20 Maj, 12:50, Benj <...@iwaynet.net
Anybody who thinks the impossible is possible, like life-after-death,
time-travel, or fountain-of-youth, is the obvious dolt. He is saying
"I'm too much of a moron to realize I am a moron."
The cosmic ray observes me to be time dilated by a factor of 10. I do
not observe such time dilation on my watch, my clock or my cells.
Observation easily disproves time dilation.
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On Sat, 23 May 2009 21:34:50 -0700 (PDT), Benj <...@iwaynet.net
On May 20, 3:43 pm, Strich-Reply-To-Idiots <...@gmail.com
Ah, one more God-like being who possesses all knowledge POSSIBLE in
the universe which is of course required to know that no way exists
for this or that to happen. Which is why these Gods can say things
"he's too much of a moron to realize he's a moron" for saying that a
motor without a commutator is impossible, that heavier than air craft
are impossible or that a "fountain of youth" is impossible even though
any biologist can tell you that at the cellular level there is no
reason that the body could not go on replacing it's cells forever.
Strich, why don't you just use the "short version" of saying that this
or that is "impossible".
Namely: "I'm an ignorant egotistical idiot!"
Ah, and you are not only a moron but a kook too! Never be "smarter
than Einstein" that way!
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On Sun, 24 May 2009 11:34:55 +0100, "Androcles" <...@Hogwarts.physics
"Benj" <...@i6g2000yqj.googlegroups.com...
On May 20, 3:43 pm, Strich-Reply-To-Idiots <...@gmail.com
Ah, one more God-like being who possesses all knowledge POSSIBLE in
the universe which is of course required to know that no way exists
for this or that to happen. Which is why these Gods can say things
"he's too much of a moron to realize he's a moron" for saying that a
motor without a commutator is impossible, that heavier than air craft
are impossible or that a "fountain of youth" is impossible even though
any biologist can tell you that at the cellular level there is no
reason that the body could not go on replacing it's cells forever.
Strich, why don't you just use the "short version" of saying that this
or that is "impossible".
Namely: "I'm an ignorant egotistical idiot!"
------------------------------------------------------------
In your case, Binj, that was never in doubt :-).
Ah, and you are not only a moron but a kook too! Never be "smarter
than Einstein" that way!
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On Mon, 25 May 2009 16:04:05 -0700 (PDT), BURT <...@yahoo.com
On May 20, 7:03 am, S T R I C H <...@gmail.com
Acceleration slows clocks and creates new motion.
There are no flat atoms.
Mitch Raemsch
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