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Dono
Guest
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 Posted: Wed Jul 16, 2008 1:15 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 15, 10:27 pm, Uncle Ben <b...@greenba.com> wrote:
| Quote: |
On Jul 16, 12:51 am, Dono <sa...@comcast.net> wrote:
You ARE trolling.
The two rockets take off simultaneously in the launcher frame and also
in the common rocket frame since, at launch, the two frames are
coincident. Find another hobby.
My analysis involves an inertial frame in which the lead rocket is
momentarily at rest or moving slowly at break time. That is what I
call the "final frame"
|
OK,
So now you changed your tune to talk about "final frame".
This is exactly the frame used on the wiki page to show that the lead
rocket STOPS accelerating later than the trailing rocket. Remember,
this is the same exact wiki analysis that you criticised earlier. So,
if your math is correct, your solution should reproduce the wiki
solution.
So far:
-you have criticised a solution that is correct
-you produced a dumbed down solution in the opening of the thread
-when pointed out that your solution is insufficient
-...you started claiming that you have yet another solution that you
aren't showing
So, until you show the other solution that you claim, you are simply
TROLLING.
Remember, most of us in this forum have extensive experience with
trolls, we can recognize them quite quickly. |
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Dono
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| Posted: Wed Jul 16, 2008 1:17 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 4:35 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
| Quote: |
Dono says...
You ARE trolling.
The two rockets take off simultaneously in the launcher frame and also
in the common rocket frame since, at launch, the two frames are
coincident. Find another hobby.
I don't know how you are misunderstanding what Uncle Ben is saying,
but Ben is right.
--
Daryl McCullough
Ithaca, NY
|
Very simple,
He has changed his statement about what he means by simultaneity
throughout the thread. He switched from "no-simultaneous at takeoff"
to "non-simultaneous in the final frame". Read my analysis of what
went on. |
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Dono
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| Posted: Wed Jul 16, 2008 1:26 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 4:32 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
| Quote: |
Dono says...
Then, your "solution" is plain wrong.
His solution is the same as that in the wikipedia article.
Let's make this more unambiguous by labeling events and frames.
Let F1 = the frame in which the two rockets are initially
at rest.
Let e1 = the event at which the rear rocket takes off.
Let e2 = the event at which the front rocket takes off.
Let e3 = the event at which the rear rocket is traveling
at 100 meters/second, relative to F1.
Let e4 = the event at which the front rocket is traveling
at 100 meters/second, relative to F1.
Let F2 = the frame in which the rear rocket is at rest at
event e3.
|
Yes, I just pointed out that Ben has switched his description from F1
to F2. He did that AFTER I pointed him to the wiki solution, a
solution that he criticised very bitterly in a long email exchange I
had with him. Now, he turns around and says that he never meant F1, he
always meant F2.
Thank you for clarifying the issue.
So, the takeway from all this is that I am waiting for Ben to produce
his math. I am curious to see haow it is different from the one on the
wiuki page :-)
> |
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Dono
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| Posted: Wed Jul 16, 2008 1:28 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 4:08 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
| Quote: |
Dono says...
On Jul 15, 7:10=A0am, Uncle Ben <b...@greenba.com> wrote:
That is all we need. If the lead rocket fires first, it must stretch
the string.
This is not what happens in the Bell problem statement.If your problem
statement were correct, the problem would reduce to a trivial one. You
keep trying to peddle your reductionist view of the problem. What
happens in reality is presented here:
http://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox#Analysis
What Uncle Ben said is completely in agreement with the wikipedia
article. I think you misunderstood Uncle Ben.
For simplicity, let's just consider two frames: (1) A frame
in which the rear rocket is at rest at time t=0, and (2) a frame
in which the rear is at rest at time t=1 second.
From the point of view of the first frame, the two rockets
launch simultaneously. From the point of view of the second
frame, the lead rocket fires first. So from the point of
view of the frame in which the string is at rest, the
string must be stretched.
--
Daryl McCullough
Ithaca, NY
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Yes, he switched meanings AFTER I pointed him to the wiki page. |
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Uncle Ben
Guest
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| Posted: Wed Jul 16, 2008 1:36 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 9:17 am, Dono <sa...@comcast.net> wrote:
| Quote: |
On Jul 16, 4:35 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
Dono says...
You ARE trolling.
The two rockets take off simultaneously in the launcher frame and also
in the common rocket frame since, at launch, the two frames are
coincident. Find another hobby.
I don't know how you are misunderstanding what Uncle Ben is saying,
but Ben is right.
--
Daryl McCullough
Ithaca, NY
Very simple,
He has changed his statement about what he means by simultaneity
throughout the thread. He switched from "no-simultaneous at takeoff"
to "non-simultaneous in the final frame". Read my analysis of what
went on.
|
State it correctly:
The two firings are simultaneous with respect to the launch frame, but
non-simultaneous w.r.t. the final frame.
Theorem: Given two events that are simultaneous w.r.t. a given
inertial frame, they are non simultaneous w.r.t. any other inertial
frame not at rest w.r.t. the first frame.
Proof: See A. Einstein, 1905, linked at my post, today, 8:30 am edt.
BTW, Dano seems to be discussing a variation on Bell's original
problem in which the rockets turn off their motors and coast. That is
not the variation I am discussing. Mine is the original problem first
discussed in the Wikipedia article Dano says he wrote. |
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Dono
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| Posted: Wed Jul 16, 2008 1:40 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 15, 9:38 pm, Uncle Ben <b...@greenba.com> wrote:
| Quote: |
I have stated in the problem that the rockets take off simultaneously
w.r.t. the launch frame. Then in the solution I said let us consider
things w.r.t. the "final frame" by which I mean the inertial frame in
which the lead rocket is moving slowly at the time of breakage
(actually at any time after launch).
|
Where did you state that? You are only stating this AFTER I pointed
you to the wiki page. Point to the actual post in this thread BEFORE
this one.
| Quote: |
The rockets do not fire
simultaneously w.r.t. the final frame. The lead rocket takes off first
w.r.t. the final frame.
|
This staement is equivalent to the one that you have already been
pointed to by me. I told you that in the string frame the lead rocket
stops accelerating LATER than the trailing rocket. Then, you turned
around and you criticised the wiki page as being too complex, as
having a gratuitous Minkowski diagram, etc.
| Quote: |
From your earlier discussions, I assumed that you were a sophisticated
relativist. But if you think there is a contradiction between
simultaneity of two events w.r.t. the launch frame and non-simltaneity
of the same two events w.r.t. the final frame, then I have to alter my
opinion.
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No, I don't have any problem with relativity of simultaneity, I
pointed it out to you in the wiki solution. rather than continuing
this trolling game, why don't you post your solution, I posted mine
right upfront. |
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Uncle Ben
Guest
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| Posted: Wed Jul 16, 2008 2:14 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 9:15 am, Dono <sa...@comcast.net> wrote:
| Quote: |
On Jul 15, 10:27 pm, Uncle Ben <b...@greenba.com> wrote:
On Jul 16, 12:51 am, Dono <sa...@comcast.net> wrote:
You ARE trolling.
The two rockets take off simultaneously in the launcher frame and also
in the common rocket frame since, at launch, the two frames are
coincident. Find another hobby.
My analysis involves an inertial frame in which the lead rocket is
momentarily at rest or moving slowly at break time. That is what I
call the "final frame"
OK,
So now you changed your tune to talk about "final frame".
This is exactly the frame used on the wiki page to show that the lead
rocket STOPS accelerating later than the trailing rocket. Remember,
this is the same exact wiki analysis that you criticised earlier. So,
if your math is correct, your solution should reproduce the wiki
solution.
So far:
-you have criticised a solution that is correct
-you produced a dumbed down solution in the opening of the thread
-when pointed out that your solution is insufficient
-...you started claiming that you have yet another solution that you
aren't showing
So, until you show the other solution that you claim, you are simply
TROLLING.
Remember, most of us in this forum have extensive experience with
trolls, we can recognize them quite quickly.
|
1. I said your solution is not to my taste. I did not say it was
incorrect.
2. |
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Uncle Ben
Guest
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| Posted: Wed Jul 16, 2008 2:24 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 9:15 am, Dono <sa...@comcast.net> wrote:
| Quote: |
On Jul 15, 10:27 pm, Uncle Ben <b...@greenba.com> wrote:
On Jul 16, 12:51 am, Dono <sa...@comcast.net> wrote:
You ARE trolling.
The two rockets take off simultaneously in the launcher frame and also
in the common rocket frame since, at launch, the two frames are
coincident. Find another hobby.
My analysis involves an inertial frame in which the lead rocket is
momentarily at rest or moving slowly at break time. That is what I
call the "final frame"
OK,
So now you changed your tune to talk about "final frame".
This is exactly the frame used on the wiki page to show that the lead
rocket STOPS accelerating later than the trailing rocket. Remember,
this is the same exact wiki analysis that you criticised earlier. So,
if your math is correct, your solution should reproduce the wiki
solution.
So far:
-you have criticised a solution that is correct
-you produced a dumbed down solution in the opening of the thread
-when pointed out that your solution is insufficient
-...you started claiming that you have yet another solution that you
aren't showing
So, until you show the other solution that you claim, you are simply
TROLLING.
Remember, most of us in this forum have extensive experience with
trolls, we can recognize them quite quickly.
|
Dono, I see what the problem is: You are not paying attention. I
introduced the "final frame" in the first exposition of my solution
and have mentioned it in almost every post since then. I can't help
you if you don't read my posts all the way through.
One man's dumbed down solution is another man's elegant solution.
I never claimed to have a second solution. I pointed out that your
solution involving the "common ship frame", an accelerated frame, was
possible to do correctly. You were being congratulated.
Could it be that you are dyslexic? It's not a crime, but it is a
handicap.
Uncle Ben |
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Dono
Guest
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| Posted: Wed Jul 16, 2008 2:35 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 5:57 am, Uncle Ben <b...@greenba.com> wrote:
| Quote: |
On Jul 16, 8:46 am, PD <TheDraperFam...@gmail.com> wrote:
On Jul 15, 10:30 pm, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
Uncle Ben wrote:
On Jul 15, 10:28 am, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
You MUST use more precise language. [...]
No, what SR says is that length of a ruler is RELATIVE, not absolute.
This means that the ruler will have different lengths with respect to
different frames of reference.
Please re-read what I wrote above. You persist in using inappropriate
(imprecise) language.
When you say "length of a ruler", if you mean WHAT ONE MEASURES then you
are correct, but that is NOT what that phrase means to most people. To
most people that phrase refers to THE length of the ruler (note emphasis
on "the", implying a SINGULAR quantity) -- this is an intrinsic property
of the ruler, and in SR when one speaks carefully (precisely) one calls
it the proper length of the ruler. But most people are not experts, and
do not understand the distinction, and thus hear "THE length of the
ruler" when you meant to say "the MEASURED length of the ruler".
Many of the confusions around here are due to inappropriate and
ambiguous language by people who should know better. Like yourself (you
seem to understand the basics of SR).
Of course some of the confusions around here are due
to pure, unadulterated idiocy.
Tom Roberts
To put Tom's point more colloquially, an given ruler at any given
moment has got thousands of physical lengths, each of them
corresponding to the physical length measured in a different reference
frame.
It so happens that the maximal length out of all those thousands will
be the one measured in the frame in which the ruler is at rest. But
there is nothing physically special about that frame, compared to
other frames, so there is nothing *physically* different about the
physical length of the ruler measured in that frame. There is the
*habit* of calling this particular length in this particular frame the
"proper length", but that is just an adjectival prefix that denotes
that this is the rest frame and the maximal length -- nothing more.
PD- Hide quoted text -
- Show quoted text -
And to add yet another liquistic comment:
If you measure it, it is real.
It is a cop-out to qualify cetain results in relativity as "apparent"
or "measured" as if measurement was a lesser way to truth. It is
because the writer is still not qjuite accepting the results as real
in the back of his mind, or he thinks the reader wont accept it and he
is hedging his bets.
That is why I always state it outright that, for example, the length
w.r.t. frame f "IS" so-and-so, not "appears to be". Length is defined
relative to a frame of reference. Doubters, get over it!
Ben-
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So,
You want to use a thought experiment that has never been run (Bell's)
and is unrunable as prove that length contraction is "real"? If this
was your agenda from the get go, why didn't you say so? |
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Uncle Ben
Guest
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| Posted: Wed Jul 16, 2008 2:37 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 9:40 am, Dono <sa...@comcast.net> wrote:
| Quote: |
On Jul 15, 9:38 pm, Uncle Ben <b...@greenba.com> wrote:
I have stated in the problem that the rockets take off simultaneously
w.r.t. the launch frame. Then in the solution I said let us consider
things w.r.t. the "final frame" by which I mean the inertial frame in
which the lead rocket is moving slowly at the time of breakage
(actually at any time after launch).
Where did you state that? You are only stating this AFTER I pointed
you to the wiki page. Point to the actual post in this thread BEFORE
this one.
|
My post of July 15, 10:10 am EDT, excepted here:
-----
"To solve the question when the string is moving at high speed, what
we
need to do is to look at it w.r.t. a frame of reference in which it
is
even now moving at a slow speed. We need to transform the frame of
reference to one in which we have some knowledge of the behavior of
strings.
"The problem is stated in terms of the launch frame, in which the
rockets are initially at rest. Keeping to this frame, the rockets
synchronize watches and simultaneously fire their engines. The
rockets accelerate; we don't need to know their equation of motion;
we just need to know that each rocket will travel the same distance
in
the same time w.r.t. the launch frame. It follows that they will
maintain the initial distance between them. Basis: the homogenity of
space.
"Fast forward 2 years w.r.t. the launch frame. Imagine a second
frame,
inertial, but w.r.t. which the lead rocket (at least) is not moving
at
unfamiliar speeds. Call this the final frame."
--------
OK?
| Quote: |
The rockets do not fire
simultaneously w.r.t. the final frame. The lead rocket takes off first
w.r.t. the final frame.
Uncle Ben |
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Dono
Guest
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| Posted: Wed Jul 16, 2008 2:50 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 7:37 am, Uncle Ben <b...@greenba.com> wrote:
| Quote: |
On Jul 16, 9:40 am, Dono <sa...@comcast.net> wrote:
On Jul 15, 9:38 pm, Uncle Ben <b...@greenba.com> wrote:
I have stated in the problem that the rockets take off simultaneously
w.r.t. the launch frame. Then in the solution I said let us consider
things w.r.t. the "final frame" by which I mean the inertial frame in
which the lead rocket is moving slowly at the time of breakage
(actually at any time after launch).
Where did you state that? You are only stating this AFTER I pointed
you to the wiki page. Point to the actual post in this thread BEFORE
this one.
My post of July 15, 10:10 am EDT, excepted here:
-----
"To solve the question when the string is moving at high speed, what
we
need to do is to look at it w.r.t. a frame of reference in which it
is
even now moving at a slow speed. We need to transform the frame of
reference to one in which we have some knowledge of the behavior of
strings.
"The problem is stated in terms of the launch frame, in which the
rockets are initially at rest. Keeping to this frame, the rockets
synchronize watches and simultaneously fire their engines. The
rockets accelerate; we don't need to know their equation of motion;
we just need to know that each rocket will travel the same distance
in
the same time w.r.t. the launch frame. It follows that they will
maintain the initial distance between them. Basis: the homogenity of
space.
"Fast forward 2 years w.r.t. the launch frame. Imagine a second
frame,
inertial, but w.r.t. which the lead rocket (at least) is not moving
at
unfamiliar speeds. Call this the final frame."
--------
OK?
The rockets do not fire
simultaneously w.r.t. the final frame. The lead rocket takes off first
w.r.t. the final frame.
Uncle Ben- Hide quoted text -
- Show quoted text -
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July 15,
AFTER I pointed out to you the correct solution on the wiki page and
the correct use of reference frames. Exactly my point. |
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Uncle Ben
Guest
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| Posted: Wed Jul 16, 2008 2:52 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 9:28 am, Dono <sa...@comcast.net> wrote:
| Quote: |
On Jul 16, 4:08 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
Dono says...
On Jul 15, 7:10=A0am, Uncle Ben <b...@greenba.com> wrote:
That is all we need. If the lead rocket fires first, it must stretch
the string.
This is not what happens in the Bell problem statement.If your problem
statement were correct, the problem would reduce to a trivial one. You
keep trying to peddle your reductionist view of the problem. What
happens in reality is presented here:
http://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox#Analysis
What Uncle Ben said is completely in agreement with the wikipedia
article. I think you misunderstood Uncle Ben.
For simplicity, let's just consider two frames: (1) A frame
in which the rear rocket is at rest at time t=0, and (2) a frame
in which the rear is at rest at time t=1 second.
From the point of view of the first frame, the two rockets
launch simultaneously. From the point of view of the second
frame, the lead rocket fires first. So from the point of
view of the frame in which the string is at rest, the
string must be stretched.
--
Daryl McCullough
Ithaca, NY
Yes, he switched meanings AFTER I pointed him to the wiki page.- Hide quoted text -
- Show quoted text -
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Dano is either dyslexic or careless.
No more wasting of time. Goodbye. |
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Dono
Guest
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| Posted: Wed Jul 16, 2008 2:52 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 6:36 am, Uncle Ben <b...@greenba.com> wrote:
| Quote: |
On Jul 16, 9:17 am, Dono <sa...@comcast.net> wrote:
On Jul 16, 4:35 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
Dono says...
You ARE trolling.
The two rockets take off simultaneously in the launcher frame and also
in the common rocket frame since, at launch, the two frames are
coincident. Find another hobby.
I don't know how you are misunderstanding what Uncle Ben is saying,
but Ben is right.
--
Daryl McCullough
Ithaca, NY
Very simple,
He has changed his statement about what he means by simultaneity
throughout the thread. He switched from "no-simultaneous at takeoff"
to "non-simultaneous in the final frame". Read my analysis of what
went on.
State it correctly:
The two firings are simultaneous with respect to the launch frame, but
non-simultaneous w.r.t. the final frame.
Theorem: Given two events that are simultaneous w.r.t. a given
inertial frame, they are non simultaneous w.r.t. any other inertial
frame not at rest w.r.t. the first frame.
Proof: See A. Einstein, 1905, linked at my post, today, 8:30 am edt.
BTW, Dano seems to be discussing a variation on Bell's original
problem in which the rockets turn off their motors and coast. That is
not the variation I am discussing. Mine is the original problem first
discussed in the Wikipedia article Dano says he wrote.- Hide quoted text -
- Show quoted text -
|
You continue to troll. Also you make reference to the private exchange
of emails where I corrected all your misconceptions. Now, you come
here and make claims that you stated the OP correctly. This is not the
case. |
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Dono
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| Posted: Wed Jul 16, 2008 2:55 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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On Jul 16, 7:52 am, Uncle Ben <b...@greenba.com> wrote:
| Quote: |
On Jul 16, 9:28 am, Dono <sa...@comcast.net> wrote:
On Jul 16, 4:08 am, stevendaryl3...@yahoo.com (Daryl McCullough)
wrote:
Dono says...
On Jul 15, 7:10=A0am, Uncle Ben <b...@greenba.com> wrote:
That is all we need. If the lead rocket fires first, it must stretch
the string.
This is not what happens in the Bell problem statement.If your problem
statement were correct, the problem would reduce to a trivial one. You
keep trying to peddle your reductionist view of the problem. What
happens in reality is presented here:
http://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox#Analysis
What Uncle Ben said is completely in agreement with the wikipedia
article. I think you misunderstood Uncle Ben.
For simplicity, let's just consider two frames: (1) A frame
in which the rear rocket is at rest at time t=0, and (2) a frame
in which the rear is at rest at time t=1 second.
From the point of view of the first frame, the two rockets
launch simultaneously. From the point of view of the second
frame, the lead rocket fires first. So from the point of
view of the frame in which the string is at rest, the
string must be stretched.
--
Daryl McCullough
Ithaca, NY
Yes, he switched meanings AFTER I pointed him to the wiki page.- Hide quoted text -
- Show quoted text -
Dano is either dyslexic or careless.
No more wasting of time. Goodbye.- Hide quoted text -
- Show quoted text -
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Better dyslexic AND careless than a dishonest troll  |
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Uncle Ben
Guest
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| Posted: Wed Jul 16, 2008 3:09 pm Post subject: Re: Are SR effects real or not? Simplified case. |
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This character who calls himself "Dano" says that he wrote the
Wikipedia article on Bell's
Paradox. He won't reveal his name, but from the character of the
exchange we have had over tha past two days, I am pretty sure I can
pick him out of the Discussion section of the Wikipedia article.
The Discussion section is many pages long if printed out. Participants
in the exchange get pretty heated and direct with each other. There
is one character there who seems to resist the suggestions of the
others. In one place, a senior member of the group accuses him of not
understanding relativity. Another accuses him of not accepting the
principle of the relativity of simulaneity, a familiar phrase from the
past few days. I don't really agree with these criticisms -- I think
he does understand -- but he has trouble grasping the writings of
others.
I won't out him here, but if you read the exchange we have had and
then read the Discussion (which takes a lot of patience), you may
agree with me as to which one is "Dano."
Uncle Ben |
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