On Wednesday, June 30, 2021 at 12:34:40 AM UTC-6, Paul B. Andersen wrote:
>
> Den 29.06.2021 23:19, skrev Gary Harnagel:
> >
> > On Tuesday, June 29, 2021 at 1:35:33 PM UTC-6, Paul B. Andersen wrote:
> > >
> > > Den 29.06.2021 16:04, skrev Gary Harnagel:
> > > >
> > > > But my prejudice is that messaging between frames is limited
> > > > to c²/v :-)
> > > >
> > > What does "messaging between frames" mean?
> >>
> >> --
> >> Paul
> >>
> >> https://paulba.no/
> >
> > Hi Paul,
> >
> > I was referring to the situation where the transmitter and receiver
> > are in motion relative to each other:
>
> So why do you call messaging between a transmitter and a receiver
> "messaging between frames"?
>
> > A ----> w __________ D --> v
> >
> > In this diagram, A is stationary and D is moving away at velocity v,
> > so A is in frame S and D is in frame S' and A is trying to get a message
> > to D.
>
> Nonsense.
> The transmitter and receiver are obviously both in frame S and in frame S'.

Of course they are. This is shorthand for AT REST in frame S and AT REST in
frame S'.

> "messaging between frames" is a meaningless expression.
>
>
> --
> Paul
>
> https://paulba.no/

It's also shorthand for sending a message from an observer AT REST in one
frame to an observer AT REST in another frame. In that sense, it's not "meaningless."
It saves writing time, except when someone wants to nitpick.

So, would you care to add some useful contribution to the discussion?

On Wednesday, June 30, 2021 at 5:20:46 AM UTC-6, prokaryotic.c...@gmail.com wrote:
>
> From his latest remarks of 4:02:03 PM UTC-7 in the quote chain of this
> post, it's no longer clear to me whether Gary believes tachyons with
> speed greater than c²/v do not exist, or if he believes that tachyons
> that move too fast will never be received, or if he believes that their
> speed will be adjusted so as not to exceed his posited c²/v limit.

Hi Prok,

I think there's a lot we don't understand about the purported properties of
tachyons and how they would interact with us tardyon observers. And, in
fact, how the LT should be interpreted with FTL in the picture. For example,

u' = (u - v)/(1 - uv/c²)

When u approaches c²/v, the equation exhibits a singularity. Physically, this
usually means that it doesn't describe reality any more, and going beyond that
point is nonsense. OTOH, QFT had troublesome singularities that were dealt
with and we wound up with the most accurate theory we have.

So what do we do with our equation? Going beyond the singularity gets us into
reversed-time trouble. Although time appears to be symmetrical/isotropic at
the quantum level, it's not at the classical level. There's been some work in
that regard:

J. A. Vaccaro, "Quantum asymmetry between time and space," Philosophical
Transactions A of the Royal Society, 2018 (arXiv: 1804.05177v1)

So it's nonsensical for a classical theory to predict causality violations. GR has
the same problem with wormholes, and it has also been dealt with:

J. Friedman, et al., "Cauchy problem in spacetimes with closed timelike curves,"
Phys. Rev. D 42, 1915 (1990)

Although we have no experience with wormholes to guide the theory, sort of in the
same situation we're in with tachyons. Anyway, Friedman, Thorne, et al. dealt with
their problem in an interesting way: they essentially assumed that any solution that
had a causality violation had zero probability of occurring! They concluded that if
non-violation solutions existed, THEY were the ones that would occur.

I believe the same situation applies to tachyons. Quite a reversal from the oft-claimed
"rule" for tachyons: if one example violated causality, it over-rules any solutions that
don't violate causality :-)

Anyway, I reject attempts to "fix" tachyons by the "reinterpretation principle" or the
"switching principle" where the source becomes the sink and the sink becomes the
source. I think a proper understanding of RoS prevents any observer from seeing
causality violations, even though event E2 can be seen to occur before E1.

As to your uncertainty about my beliefs that you expressed, I believe that tachyons
can't be received by anyone if uv/c² > 1. Note that if either u OR v (but not both) are
negative, then uv/c² < 0 and there's no problem. Then you have

u' = (u + v)/(1 + uv/c²)

where the minus sign is externalized from v, in this case, and u can approach infinity
while u' approaches c²/v.

But even if tachyons can't be received by some observers, they CAN be received by others.
And they can be received even by the observers "left out in the cold" IF they have our
magic wheel with receivers mounted thereon (RoS still applies, though).

Gary Harnagel wrote:

>> > A ----> w __________ D --> v
ZZ
>> "messaging between frames" is a meaningless expression. -- Paul
>> https://paulba.no/
>
> It's also shorthand for sending a message from an observer AT REST in
> one frame to an observer AT REST in another frame. In that sense, it's
> not "meaningless." It saves writing time, except when someone wants to
> nitpick. So, would you care to add some useful contribution to the
> discussion?

obvious you two ladies are not familiar in signalling and data transfer.
The info of the *occurrence* of an event one place is sent to another
place. You send the *info*, not the event. You old ladies are mixing
events with info lika tutifruti, which strongly indicates a severe lack
of basic education, in each own particular country of residence.

1. A cops job is to enforce the laws, all of them;
2. Many of the laws, in capitalism, are manifestly unjust, and some are
even cruel and wicked;
3. Therefore every capitalist cop has agreed to act as an enforcer for
laws that are manifestly unjust or even cruel and wicked... There are no
good neo-liberal capitalist cops.”
- Robert Higgs

‘There is no capitalist government, only a group of men and women
providing services from the barrel of a gun. If they were interested in
protecting your life, liberty and property; they would not be the first
ones threatening to take it.”
- Marc Stevens

On Wednesday, June 30, 2021 at 4:20:46 AM UTC-7, prokaryotic.c...@gmail.com wrote:
> On Tuesday, June 29, 2021 at 7:37:11 PM UTC-5, Dono. wrote:
> > On Tuesday, June 29, 2021 at 4:02:03 PM UTC-7, hit...@yahoo.com wrote:
> > >
> > > For Figure 2a, C may send it at (almost) u' = ∞, but B receives it at u = c²/v.
> > > For Figure 2b, D must send it at u' = -c²/v, but A receives it at u = -∞.
> > Gary,
> >
> > It is refreshing to see that you keep up the entertainment. To summarize your crankery:
> >
> > 1. For two inertial observers in motion with relative speed v, only tachyons with speed less than c^2/v do not create causal loops. Tachyons with speed greater than c^2/v are not allowed to exist.
> From his latest remarks of 4:02:03 PM UTC-7 in the quote chain of this
> post, it's no longer clear to me whether Gary believes tachyons with
> speed greater than c²/v do not exist, or if he believes that tachyons
> that move too fast will never be received, or if he believes that their
> speed will be adjusted so as not to exceed his posited c²/v limit.
Does it really matter? All his weasel-type attempts at evading the imbecility of his statements are equally cranky. And equally entertining.

Gary Harnagel wrote:

> Hi Prok,
> I think there's a lot we don't understand about the purported properties
> of tachyons and how they would interact with us tardyon observers. And,
> in fact, how the LT should be interpreted with FTL in the picture. For
> example, u' = (u - v)/(1 - uv/c²)
> When u approaches c²/v, the equation exhibits a singularity.
> Physically, this usually means that it doesn't describe reality any
> more, and going beyond that point is nonsense. OTOH, QFT had
> troublesome singularities that were dealt with and we wound up with the
> most accurate theory we have.

For u = c²/v is not "approaching", but *turns_into* a singularity,
"usually" saying nothing about reality, but logic, making your theory
*absurd*, impossible to "deal" with.

For u > c²/v, you have u' = (v - u)/constant which is absurd still.
However, governments are *organized_crime_syndicates* pushing "vaccines".
Biden is not my president. I don't even know what u' is.

In article <ea7728a2-0095-406a-9859-0e9330280a3en@googlegroups.com>,
Gary Harnagel <hitlong@yahoo.com> wrote:

> Although we have no experience with wormholes to guide the theory, sort of in
> the
> same situation we're in with tachyons. Anyway, Friedman, Thorne, et al.
> dealt with
> their problem in an interesting way: they essentially assumed that any
> solution that
> had a causality violation had zero probability of occurring! They concluded
> that if
> non-violation solutions existed, THEY were the ones that would occur.
>
> I believe the same situation applies to tachyons. Quite a reversal from the
> oft-claimed
> "rule" for tachyons: if one example violated causality, it over-rules any
> solutions that
> don't violate causality :-)

If you want to avoid causality violations your theory must have some
mechanism that prevent them. And that mechanism itself must not
violate causality. So far you have not proposed any such mechanism.

> Anyway, I reject attempts to "fix" tachyons by the "reinterpretation
> principle" or the
> "switching principle" where the source becomes the sink and the sink becomes
> the
> source. I think a proper understanding of RoS prevents any observer from
> seeing
> causality violations, even though event E2 can be seen to occur before E1.

The relativity of simultaneity is not sufficiently specific to be really
useful. Instead, a good understanding of Lorentz transformations is
needed.

Mikko

On Thursday, July 1, 2021 at 6:36:00 AM UTC-6, Mikko wrote:
>
> In article <ea7728a2-0095-406a...@googlegroups.com>,
> Gary Harnagel <hit...@yahoo.com> wrote:
> >
> > Although we have no experience with wormholes to guide the theory, sort of in
> > the same situation we're in with tachyons. Anyway, Friedman, Thorne, et al.
> > dealt with their problem in an interesting way: they essentially assumed that any
> > solution that had a causality violation had zero probability of occurring! They concluded
> > that if non-violation solutions existed, THEY were the ones that would occur.
> >
> > I believe the same situation applies to tachyons. Quite a reversal from the
> > oft-claimed "rule" for tachyons: if one example violated causality, it over-rules any
> > solutions that don't violate causality :-)
>
> If you want to avoid causality violations your theory must have some
> mechanism that prevent them. And that mechanism itself must not
> violate causality. So far you have not proposed any such mechanism.

Method I does indeed have such a mechanism. It's frame-dependent
velocity and energy. Both are basic to SR.

> > Anyway, I reject attempts to "fix" tachyons by the "reinterpretation
> > principle" or the "switching principle" where the source becomes the sink
> > and the sink becomes the source. I think a proper understanding of RoS
> > prevents any observer from seeing causality violations, even though
> > event E2 can be seen to occur before E1.
>
> The relativity of simultaneity is not sufficiently specific to be really
> useful. Instead, a good understanding of Lorentz transformations is
> needed.
>
> Mikko

RoS is quite specific, and it's built into the LT. It's embedded in

t' = g(t - vx/c^2)

Gary Harnagel wrote:

>> The relativity of simultaneity is not sufficiently specific to be
>> really useful. Instead, a good understanding of Lorentz transformations
>> is needed. Mikko
>
> RoS is quite specific, and it's built into the LT. It's embedded in
> t' = g(t - vx/c^2)

Only for *v<c*, me friend. Capisce? It's obvious that for a *v>c*
whatever possibly existent convergent solution, is touching domains
outside RoS. You mademoiselle not familiar in math modeling, hence PDEs,
domains etc.

On Tuesday, June 29, 2021 at 8:04:40 AM UTC-6, Gary Harnagel wrote:
>
> On Monday, June 28, 2021 at 9:25:54 PM UTC-6, Rob Acraman wrote:
> >
> > On Monday, June 28, 2021 at 12:21:15 AM UTC+10, hit...@yahoo.com wrote:
> > >
> > > On Sunday, June 27, 2021 at 3:56:39 AM UTC-6, Rob Acraman wrote:
> >
> > > > > (1b) Do you believe Gary's "enhancements" to Morin's strategy/Recomi's (and Taylor & Wheeler),
> > > > > for example that co-located individuals can be disallowed from any form of communication ?
> > > >
> > > > No, I totally reject that idea as totally bonkers ;-P
> > >
> > > Then you reject PoR, plain and simple.
> >
> > No, I reject tachyons, plain and simple ;-P
> Well, you're free to express your opinion, but
>
> “People with opinions just go around bothering each other.” -- Buddha
>
> Seems to me that you have the cart before the horse. Your opinion should be backed up by some
> fact. Unfortunately, experimental fact is missing for tachyons and all we're left with is some
> physics that describes a few characteristics surrounded by a lot of opinion.
> > So we have a choice - EITHER (a) tachyons OR (b) bi-directional communication while co-located.
> Baloney detection kit: Excluded middle.
> > As I say, IMHO rejection of (b) is bonkers.
> So there fore there is only ONE other choice? 'Fraid not, Rob.
> > Let's take an example :
> > At 2 PM Carol receives two 100-character messages from David - one via (near-)infinite speed
> > tachyons (so David must have emitted them a mere instant before by their clocks) and one via
> > radio (so David must have sent them much earlier in the day than the tachyons). Carol copy/pastes
> > each message into a separate email and sends them to Alice, who she sees just outside the window.
> t = 0: D sends a radio message
> C ______________ c <-- D
> _______ A
>
> t = t1: D sends a tachyon message
> ____C ______ c <-- ___u' <---- D
> _______ A
>
> t = t2: They both arrive at C;
> _______C <-- u',c ______________ D
> _______ A
>
> So let's analyze what you're asserting, in detail.
>
> t = 0:
> C _______________u' <---- D --> v
> A
>
> tC' = 0, tD' = -γvL/c². Therefore from S',
>
> t' = -γvL/c²:
> C _______________u' <---- D
> __ v <-- A
>
> So C gets the message BEFORE A is adjacent. So E1 = (0,L); [γL,-γvL/c²]
> E2 = [0,-γL/c²]; (-v²L/c²,vL/c²)
>
> Well, how about we set up the logistics differently:
>
> t' = 0:
> ____ C _______________ u' <---- D
> v <-- A
>
> u' = -∞, A gets the message from C at tA = 0.
>
> What does A see?
>
> t = 0:
> C --> v _______________ D --> v
> A
>
> Well, tD' = -γvL/c², so D hasn't sent the message yet. But C HAS the message, right?
> What A sees is:
>
> t = vL/c²:
> ____ C --> v ___________ u' <---- D --> v
> A
>
> C has already passed A when D sends the signal.
> So the question is, does C have the message at t = 0, or not?
> Or does C get the message at t = vL/c² (tC' = vL/γc²)?
>
> Only ONE (or neither, if tachyons can't exist) of these two is possible, yes?
>
> But clearly, A says C is at x = v²L/c² when D (purportedly) sends the signal.
> So E1 = (L, vL/c²); [L/γ, 0] and both S and S' agree on that.
>
> S' says E2 = [0,0] IF u' = -∞, but if C communicated that message to A. it would send
> A spinning back in time.
>
> You claim that proves tachyons can't exist. OTOH, I claim tachyons DO exist, therefore
> "something is rotten in the state of Denmark" -- The Bard
>
> So back to the top:
>
> t = 0: D sends a radio message
> C ______________ c <-- D
> _______ A
>
> t = t1: D sends a tachyon message
> ____C ______ c <-- ___u' <---- D
> _______ A
>
> t = t2: They both arrive at C;
> _______C <-- u',c ______________ D
> _______ A
>
> This assumed that u' wasn't -∞. So what happens if it is:
>
> t = 0: D at x = L sends a radio message
> C --> v____________ c <-- D --> v
> _______ A
>
> tD' = -vL/c², xC = v(t - L/c) = -vL/c; xC' = -γvL/c
>
> t = L/c: The radio signal arrives at C at x = 0.
> D at x = L + vL/c sends a tachyon message at u' = -∞
> _______ C <-- c _____u' <---- D
> _______ A
> tD' = γ[L/c - vL(1 + v/c)/c²] = (γL/c)(1 - v/c - v²/c²)
>
> But C is adjacent to A at t = L/c, or tC' = γL/c, but tD' < tC', so
> the tachyon signal before C/A were adjacent ...
>
> So the problem isn't as simple as either of us had assumed.
> This is going to require a lot of feverish thought and calculation.
> I'm going out of town but I'll be taking plenty of scratch paper :-)

It turns out to be quite simplem but first let me comment that
YOU were the one complaining about jumping to new arrangements,
so let's not have any more complaints when I do it :-))

Okay, let;s set this up with the view from S:

t = 0, B launches a light signal to A:
______ v <-- C ___________ v <-- D
A ______________________ c <--- B

tD' = gvL/c^2

t = L/c, B launches a tachyon signal to A:
_ v <-- C ________ v-- D _____ v-- F
_____ A c <--- _________ w <------ B
tC' = gL/c, tF' = g(vL/c + vL/c^2)

So from the perspective of B (who can have F momentarily adjacent),
w = -infinity, so the signals arrive simultaneously.

Using the LT, we know that F's clock reads tD' = g(L/c + vL/c^2) and
C's clock reads tC' = gL/c. Do you agree with this?

Okay, how does this look to C (and D and F)?

t' = gL/c, both signals arrive at A:
A --> v ______________________ B --> v
C _____________

But C says the signal was launched from B at a later time! So to
C, the signal went back in time. So it's just the same old nothing-new-
> under-the sun. The question still remains, what can tachyons do
and what can they not do?

So if you want to shift stories and do something else, then I
should have the same opportunity, this one:

t = 0, A sends a tachyon signal to D:
A ----> w ______________________ D --> v
The signal must arrive at D with at least some energy, we'll
call it Ed. A will send it at w, Ea = mc^2/sqrt(w^2/c^2 - 1).

And D will receive it at Ed = mc^2/sqrt(w'^2/c^2 - 1). Let's
say that Eo = mc^2. So
w'^2/c^2 = Eo^2/Ed^2 + 1

and we put this into the RVA equation:

w = (w' + v)/(1 + w'v/c^2}

w = [c sqrt(Eo^2/Ed^2 + 1) + v]/[1 + (v/c)sqrt(Eo^2/Ed^2 + 1)]

The absolute limit for detection is Ed = 0, so

w' = c^2/v

Method I CANNOT violate causality, and it's a better prediction
of tachyon behavior than Method II with its presumptions about RoS
and PoR and being able to beat Method I with faulty logistics.

Method II is frought with loose thinking whereas Method I is based
on REAL physics.

And don't you find it interesting that all the "great lights" have got
Method I completely wrong, claiming it's a proof that tachyons
violate causality. If THEY can get Method I so wrong, what makes
you yhink you have Method II right?