Re: Tracking

Logan Kearsley wrote:
"Mark L. Fergerson" <mfergerson1@xxxxxxx> wrote in message
news:hCT3g.157354$Oe2.37677@xxxxxxxxxxxxx

MajorOz wrote:

The bad guy is chasing the good guy. The GG jumps to warp speed and
disappearss. The BG says to his near by tekke: "track them using the
_________ trail that they are leaving."

Given the premise of FTL, what possible "trail" could there be?

As has been said, it depends on how the FTL drive works.

Hrm. Would Alcubierre-type g-warps radiate the gravitational
equivalent of Cerenkov radiation? Of course I'm assuming there is such
an equivalent, taking Lense-Thirring to be the nub of a gravitational
analog of magnetism a la Forward's "protational" field. If so, the
c-equivalent would be called "GravitoProtational radiation" instead of
the current "gravitational radiation", and the Cerenkov-analogous
FTL/STL trace would reasonably be supposable to have somebody's name
tacked on; I'm tempted to claim it as "Fergerson Radiation" except
somebody else has prolly already thought of it...

I don't think so. Cerenkov radiation emitted by charged particles in a
medium depends on the relative speed of the particles wrt the medium.

Well, I'm positing (OK, handwaving) a gravitational analog to Cerenkov, hence "charge" must analogize to "mass".

You
can't determine a speed relative to space without instituting some sort of
preferred frame,

I keep seeing claims that Alcubierre doesn't violate either of the Relativities (isn't unphysical). That seems to imply that there actually _is_ a preferred frame, where all luxons (including gravitons, the quanta of the GraviProtational field) live.

so the next obvious thing to do is just to emit radiation
in the frame of the particle, but in that case the emitted radiation must be
FTL as well, or else it ends up with imaginary wavelength due to Doppler
shift.

I don't follow. Any form of Cerenkov must travel at c, otherwise we couldn't see it. This means that c is the "default" velocity of luxons, when they aren't traveling in some medium other than the New Improved Aether.

(When I say "any form" I'm thinking of something possessing any conserved charge exceeding c.)

For all we know ordinary Cerenkov _does_ travel above c for a while immediately after emission, possibly some sort of "near field" effect? Hence _observable_ Cerenkov is only the "far field" part.

But who knows? Maybe imaginary wavelength actually does have some physical
interpretation.

Ooh. In this case, imaginary deBroglie wavelength? Naively the "length" would rotate into the "time" axis, so Near By Tekke would have to call out the wavelength in seconds. To maintain consistency (never mind physicality) I suppose one would have to redact the derivation of deBroglie wavelength altogether dimensional analysis-wise, taking into account some coherent way of expressing the FTL momentum of an Alcubierre-driven ship.


Mark L. Fergerson

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Relevant Pages

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