Marcel Luttgens wrote:
Bjoern Feuerbacher wrote in message ...

Marcel Luttgens wrote:

Bjoern Feuerbacher wrote in message ...


Marcel Luttgens wrote:


SR time dilation on remote objects ?


A remark to all GRists:

Instead of quibbling about formulae incorporating the "assumed"
space expansion, (pseudo-)cosmologists should better give their opinion
about

The "Triplets" thought experiment (Adapted from the "Twin paradox")

Why? It is irrelevant for the cosmological time dilation.


Why is it irrelevant?

Because you keep acting as if the cosmological time dilation had
to do something with the velocity.


Are not remote galaxies receeding from
Earth with some velocity, which is a function of their distance?
Is such velocity only "apparent", Iow not real?

I already told you that the recession of the galaxies is due to
the space between them and us expanding.


If it is a mere
illusion, how do you explain the Doppler shift?

The red shift is not a Doppler shift - it occurs due to the expansion
pf space. I already told you that, too - didn't you listen, or have you
forgotten that already?


And if it is real (for those believing in expansion of course,
I have to dot the i's), and some galaxy at distance d from Earth
moves at v wrt the Earth, does not the Earth moves at the same
velocity wrt the galaxy?

Seen from that galaxy, the Earth seems to move at the
same speed (but obviously in the opposite direction).


For an Earth observer, is not the time
on the galaxy slowed down by some factor wrt the time on Earth?

The time *seems* to have moved slower when the light we observe now on
Earth left that galaxy.


And for the galactic observer, is not time on Earth slowed
down by the same factor wrt its own time?

The time *seems* to have moved slower when the light they observe now on
in that galaxy left the Earth.


Does this not logically
mean that the Earth clock and the galactic clock tick at the same
rate,

No, not at all. Why on earth do you think so?


as confirmed by Terence in the "Triplets thought experiment"?

That thought experiment confirms nothing like that.


As both clocks tick at the same rate,

Now they do. When the light left the source, the clocks seem
to have ticked at a different rate than they now do.


how can the contemporary
cosmologists claim that a time dilation factor of (1 + z) works
on supernovae to lessen the delay in the rest frame?

Drop the rhetoric and look at the actual calculations.


I am looking forward to reading your comments.

I am looking forward to you misunderstanding them yet again.



"Terence sits at home on Earth. Galaxy (yes, it's her name)
flies off in a space ship at a velocity v/2. Simultaneously,
Terra (also a name) flies off in the opposite direction at -v/2.
After a while, Terra, who considers that Galaxy flies away
from her at a velocity v,

Why should Terra consider that? Does she not know how to
add velocities in SR?



You don't seem to grasp the spirit of Terra's claim, which
is that Galaxy is flying away from her at some velocity.

We are talking about measurements here, not about "spirit".


claims that Galaxy is now younger
than her, exactly like GRists claim that time goes slower on
SN because of space expansion.

That is in no way "exactly like".



Don't GRists make such claim? Remove "exactly" if you prefer.

GR say that time seems to have gone slower on the SN when the
light was emitted. Not that *today*, time *still* goes slower on the SN.



According to Terence, both Terra and the GRists are wrong,

There *is* no "right" or "wrong" here. Who is younger depends
on the frame of reference. There is no "absolute time".



This is trivial.

Then why do you say something nonsensical like "both Terra and
the GRists are wrong"?



because Terra's clock and Galaxy's clock tick at the same
rate."

Right. And still irrelevant for cosmology.



Right, what a nice and honest concession!

But *not* irrelevant for cosmology: both clocks tick at the same
rate, not only according to Terence,

Wrong. *Only* according to Terence.


but also, logically, to Terra and Galaxy,

Why is that logical?


who both should apply the Cosmological Principle.

What on earth has this to do with the Cosmological Principle?


Iow, they should know that the time slowing effect due to expansion
is symmetrical,

I am still not sure what you mean by "symmetrical" here.


and therefore conclude, contrary to the claims by
illogical relativistic cosmologists, to the absence of any observable
time dilation effect on remote objects like supernovae.

Absolute total utter non sequitur.


Till now, none of them dared to comment.
They should at least try to demonstrate that Terence is wrong.

No. In his frame of reference, he is perfectly right.



Fine.

Note the words "in his frame of reference". They are crucial here.



In their frames of references, both Galaxy and Terra are also
perfectly right to claim that the other one is younger.

And this is still irrelevant for cosmology.



Could you elaborate,

About what, specifically?


not forgetting elementary logic?

You seem to have a quite different idea of "logic" than I.



This also would be fine.

[Ad hominem comments snipped]

Says the one who continues to libel cosmologists.


Bye,
Bjoern