[ExI] QT and SR

Jeff Davis jrd1415 at gmail.com
Fri Aug 8 08:51:35 UTC 2008

On Wed, Aug 6, 2008 at 10:32 PM, Lee Corbin <lcorbin at rawbw.com> wrote:
> Jeff wrote (Sent: Monday, August 04, 2008 9:53 PM)
>> On Thu, Jul 17, 2008 at 3:20 PM, Lee Corbin <lcorbin at rawbw.com>
>>> Well, the solution is what has been pointed to in a number of web links.
>>> Namely, to wit, viz., the strings do break.
>> The "solution" is wrong.  The strings do not break.
> Bell, as you state, was indeed a very bright fellow, even better
> at physics than most of the demi-gods at CERN.

Really, Lee, aren't you putting these guys on a pedestal.  I mean
after all, they're only **demi-**gods. ;-}

> The a priori
> odds of you being right and him being wrong (along with all
> those web references) may be small,

Odds implies statistics.  Statistics implies a sampling.  We have here
a sampling of one.  One disagreement between me and Bell (presuming
that Bell himself thought the strings would break -- I'd like to see
some corroboration for that.  Maybe you got it wrong and Bell
**doesn't** think the strings would break.  Then it would be a case of
a single incidence of Bell and me agreeing.  Far more likely in my
view.) Either way, the sampling is too small to derive any meaningful
"odds".  ;-}  But no matter.  Like you said:

> but we must never argue
> from authority!
>> There are two easy ways to see this.  First, If you were on board the
>> space ships, in which frame of reference the laws of physics would
>> operate in pedestrian fashion, where is there any reason for the
>> strings to break?
> Your "line of simultaneity" shifts as your velocity increases.

"My" line, by which you mean the line of someone outside the
ships/strings frame of reference.  But then you go back into the
ships/strings frame of reference and cite the sleepy cabin officer's
view of things.  Isn't there some inconsistency here?  I mean frame if
reference -wise?

> A cabin officer who slept through the takeoff would, looking
> at the velocities of the other ships, calculate that they had
> departed the vicinity of the Earth earlier than his own ship,
> and that his ship had taken off before the ones behind him,
> contrary to the admiralty's orders.

No, he would wake up, find the fleet in perfect formation, absolutely
motionless with respect to one another, with each and every clock
clicking in precise unison. and all lengths undistorted, all strings
intact.  He would conclude that the fleet  had executed a simultaneous
departure precisely as planned.

> In fact, if the line of space ships was long enough, he'd be able
> to calculate from certain observations that a number of them were
> still on the runway "right now".

It was my impression that the fleet was assembled in space, in line,
with thirty meters (of string) between each, with each individual ship
then accelerating the same as every other.  The strings intact, at
least initially.

>> Second, replace all that spaceship and string stuff with a long
>> ruler with alternating sections marked "spaceship" and "string".
> Very good approach, said Lee, trying hard not to be patronizing.
>> Accelerate the ruler according to the same regime. Will the
>> sections marked "string" break?
> No. You're right about that!
>> Will the ruler break anywhere?
> No.  Also correct.  But equip the rear end of each portion of
> those segments marked "spaceship" with their very own
> hyper-powerful nucleonic tasmodic interrocitor (some, certainly
> not you, probably think I'm making up that word) engines,
> and the ruler does break.

The problem here is that the original premise/question seemed to
suggest another mechanism of breakage. That whatever breakage might
occur, would occur due to some hypothetical strain placed on the
strings as a result of the Lorentz contraction.  More specifically,
the Lorentz contraction applies to  strings and ships, which are
supposed to shrink, but not to the **space** (or as John Clark refers
to it: "empty space") between.  The persons on board the ships are
charged with maintaining matching acceleration profiles  AND
maintaining the original spacing -- thirty meters -- between ships,
with the notion that the Lorentz contraction will shorten the string,
whereupon the ship drivers will need to distinguish between the
**original** thirty-meter lengths of the strings and the new and
shorter Lorentz contracted lengths, and adjust their station keeping
to maintain the **original**  separation, which is supposedly longer
than the **shortened** strings.

No.  This is classic reference frame misuse.  Personnel on board the
ships will see that everything remains spacialy correct, with the
original thirty meters steady between ships and the strings stable and
steady at thirty meters each.  If they were to make a calculation of
the Lorentz contraction and conclude that they must adjust their
positions to a slightly greater separation distance, their measuring
instruments would nonetheless indicate the distance to be greater than
thirty meters, **in their reference frame**.  The
apparently-thirty-meter-long strings would certainly break under these
circumstances, but the ships would at the same time not at all seem to
be maintaining the same spacing as they held when they initially set

> In fact, I have long suspected *you* of being the author of
> http://www.shipbrook.com/jeff/interocitor/
> so your little "poor confused little me" trick isn't working.
> "Jeff Lee" indeed.   Thanks, but no thanks.

I'll take a look.  Sometimes I have black outs, and wake up in strange
places with people I don't know who call me strange names. ;-}

Best, Jeff Davis

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