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Re: The Speeed of Light

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  Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-08 20:02 +0100
    Re: The Speeed of Light Libor 'Poutnik' Stříž <poutnik@privacy.net> - 2018-04-08 22:03 +0200
      Re: The Speeed of Light Lofty Goat <rlwatkins@gmail.com> - 2018-05-05 22:16 -0500
    Re: The Speeed of Light Edward Prochak <edprochak@gmail.com> - 2018-04-08 18:10 -0700
    Re: The Speeed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-09 09:39 -0500
      Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-09 16:04 +0100
        Re: The Speeed of Light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-04-09 18:16 +0200
          GPS satellites. Jeff-Relf.Me  @. - 2018-04-09 10:45 -0700
            Re: GPS satellites. "reber G=emc^2" <herbertglazier0@gmail.com> - 2018-04-09 11:33 -0700
              Re: GPS satellites. "hanson" <hanson@quick.net> - 2018-04-09 12:34 -0700
            Re: GPS satellites. J. Clarke <jclarke.873638@gmail.com> - 2018-04-09 23:28 -0400
              GPS satellites. Jeff-Relf.Me  @. - 2018-04-09 20:49 -0700
              Re: GPS satellites. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-04-10 06:00 +0200
              Re: GPS satellites. Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-11 14:36 -0500
                Re: GPS satellites. J. Clarke <jclarke.873638@gmail.com> - 2018-04-11 22:22 -0400
                  Re: GPS satellites. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-04-12 04:38 +0200
        Re: The Speeed of Light Edward Prochak <edprochak@gmail.com> - 2018-04-09 09:51 -0700
        Re: The Speeed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-09 14:00 -0500
        Re: The Speeed of Light Odd Bodkin <bodkinodd@gmail.com> - 2018-04-09 19:34 +0000
        Re: The Speeed of Light Lofty Goat <rlwatkins@gmail.com> - 2018-04-09 21:10 -0500
          Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-10 17:56 +0100
            Re: The Speeed of Light Odd Bodkin <bodkinodd@gmail.com> - 2018-04-10 18:39 +0000
            Re: The Speeed of Light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-04-10 20:40 +0200
            Re: The Speeed of Light Lofty Goat <rlwatkins@gmail.com> - 2018-04-10 14:23 -0500
              LET EXPERIMENT DECIDE ('cos i think Relativists are Charlatans eh!) Keith Stein <keithstein111@gmail.com> - 2018-04-10 21:28 +0100
            Re: The Speeed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-14 09:11 -0500
              Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-14 18:44 +0100
      Re: The Speeed of Light Whisper <beaver999@ozemail.com> - 2018-04-10 20:43 +1000
        Speed of light (was: The Speeed of Light) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-04-12 06:25 +0200
    Re: The Speeed of Light Edward Prochak <edprochak@gmail.com> - 2018-04-11 09:58 -0700

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#680349 — Re: The Speeed of Light

The speed of light in vacuum is a silly concept,
because what can this speed be relative to ?

But since there is FINITE DENSITY EVERYWHERE,
there is no need to solve this conundrum.

LIGHT TRAVELS RELATIVE TO THE STUFF IT IS TRAVELING THROUGH,
AS DOES EVERY OTHER TYPE OF WAVE TOO.

Don't tell me i'm wrong, rather tell me what experiment proves what i 
say is not true eh!

keith stein

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#680357

Dne 08/04/2018 v 21:02 Keith Stein napsal(a):
> The speed of light in vacuum is a silly concept,
> because what can this speed be relative to ?

Any speed relates to a coordinate system.
So does speed of light in vacuum.
> 
> But since there is FINITE DENSITY EVERYWHERE,
> there is no need to solve this conundrum.

As it is solved already.
There is strong convergence toward vacuum,
as I pointed out in other post.
> 
> LIGHT TRAVELS RELATIVE TO THE STUFF IT IS TRAVELING THROUGH,
> AS DOES EVERY OTHER TYPE OF WAVE TOO.

Shouting is not more true than whispering.

Light travels relative to any coordinate system,
implicit or explicit, like any other wave.

> 
> Don't tell me i'm wrong, rather tell me what experiment proves what i
> say is not true eh!

The education experiment.

-- 
Poutnik ( The Pilgrim, Der Wanderer )

A wise man guards words he says,
as they say about him more,
than he says about the subject.

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#683957

On Sun, 8 Apr 2018 22:03:23 +0200, Libor 'Poutnik' St?íž wrote:

> ... The education experiment.

Many people should perform this experiment much more often.

-- 
Goat / RLW

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#680393

On Sunday, April 8, 2018 at 3:02:59 PM UTC-4, Keith Stein wrote:
> The speed of light in vacuum is a silly concept,
> because what can this speed be relative to ?
> 
> But since there is FINITE DENSITY EVERYWHERE,
> there is no need to solve this conundrum.
> 
> LIGHT TRAVELS RELATIVE TO THE STUFF IT IS TRAVELING THROUGH,
> AS DOES EVERY OTHER TYPE OF WAVE TOO.

Nothing you say contradicts SOLIV as a constant forming the basis
of Special and General Relativity.

> 
> Don't tell me i'm wrong, rather tell me what experiment proves what i 
> say is not true eh!

Same challenge back to you.
  Ed

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#680434

On 4/8/18 2:02 PM, Keith Stein wrote:
> The speed of light in vacuum is a silly concept,
> because what can this speed be relative to ?

Like ALL speeds, it is relative to the coordinates used to measure it.

By convention, physicists use locally inertial coordinates unless otherwise 
specified. Around here that convention is not so well established (mostly 
because many people don't understand the need for it).

Tom Roberts

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#680437

On 09/04/2018 15:39, Tom Roberts wrote:
> On 4/8/18 2:02 PM, Keith Stein wrote:
>> The speed of light in vacuum is a silly concept,
>> because what can this speed be relative to ?
> 
> Like ALL speeds, it is relative to the coordinates used to measure it.

:)  What is 'silly' Mr.Roberts is to believe that the velocity of any 
given light beam could possibly be the same value 'c' relative to all 
inertial coordinates, irrespective of how those coordinates are moving 
relative to each other.

> By convention, physicists use locally inertial coordinates unless 
> otherwise specified. Around here that convention is not so well 
> established (mostly because many people don't understand the need for it).
> 
> Tom Roberts
> 

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#680452

Keith Stein <keithstein111@gmail.com> Wrote in message:
> On 09/04/2018 15:39, Tom Roberts wrote:
>> On 4/8/18 2:02 PM, Keith Stein wrote:
>>> The speed of light in vacuum is a silly concept,
>>> because what can this speed be relative to ?
>> 
>> Like ALL speeds, it is relative to the coordinates used to measure it.
> 
> :)  What is 'silly' Mr.Roberts is to believe that the velocity of any 
> given light beam could possibly be the same value 'c' relative to all 
> inertial coordinates, irrespective of how those coordinates are moving 
> relative to each other.

Welcome to the silly nature. It does not care if what it does is
 silly. 

The observer independent speed is nothing, compared to behaviour
 of quantum objects. 

Silly behaviour cannot be properly  described by models that are
 not silly enough  for common sense.



-- 
Libor Striz aka Poutnik ( a pilgrim/wanderer/wayfarer)


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

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#680470 — GPS satellites.

> common sense.

GPS satellites are the perfect way to explain relativity,
because everyone can relate to it.

On Earth, the satellite's signal is BlueShifted by gravity
and RedShifted by its velocity, relative to earth's core.

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#680480 — Re: GPS satellites.

On Monday, April 9, 2018 at 10:45:57 AM UTC-7, Jeff-Relf.Me wrote:
> > common sense.
> 
> GPS satellites are the perfect way to explain relativity,
> because everyone can relate to it.
> 
> On Earth, the satellite's signal is BlueShifted by gravity
> and RedShifted by its velocity, relative to earth's core.

Spin direction fits best.Red if light source is turning away from you.Blue if coming at you.Seen side ways light is a strick.Bert

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#680496 — Re: GPS satellites.

___"reber G=EMC^2"<herbertglazier0@gmail.com> wrote 
to "Jeff-Relf.Me" who said:
"Cocaine caused the AIDS epidemic.
cocaine wears down the immune system.
For liability reasons, doctors _must_ treat cancer,
even when they know that the cancer might be 
dormant, depending on the immune system."
>
SwineBert wrote:
"I use Cocaine that is a wonder-drug for me". Bert.
"I will do even more Drugs till the end of my time". Ber
"I am a first class low wit bigot.  Sad and so true. Bert"
"I park & bark in the dark. I'm of low wit & a stupid shit." Bert
>
"Why am I posting this, it's making me cry as it always does".Bert
>
______  "Why am I not loved by all?". Bert.
>

>
>
>
hmmm...So, SwineBert has AIDS.O ya. Go figure
<snicker>...<chortle>...ahahahAHAHA...ROTFLMAO

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#680563 — Re: GPS satellites.

On Mon, 09 Apr 2018 10:45:53 -0700 (Seattle), Jeff-Relf.Me  @. wrote:

>> common sense.
>
>GPS satellites are the perfect way to explain relativity,
>because everyone can relate to it.
>
>On Earth, the satellite's signal is BlueShifted by gravity
>and RedShifted by its velocity, relative to earth's core.

While that is true, the relativistic correction in GPS satellites is
in the timebase, not the transmission frequency.

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#680564 — GPS satellites.

> > GPS satellites are the perfect way to explain relativity,
> > because everyone can relate to it.
> > 
> > On Earth, the satellite's signal is BlueShifted by gravity
> > and RedShifted by its velocity, relative to earth's core.
> 
> While that is true, the relativistic correction in GPS satellites
> is in the timebase, not the transmission frequency.

Relativity is used to adjust the frequency of the orbiting clocks;
c, the speed of light, is a known constant;
so time and distance are easily derived.

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#680565 — Re: GPS satellites.

J.  Clarke amok-crossposted to 4 newsgroups:
^^
Your first name belongs there.

> On Mon, 09 Apr 2018 10:45:53 -0700 (Seattle), Jeff-Relf.Me  @. wrote:
>> GPS satellites are the perfect way to explain relativity,
>> because everyone can relate to it.
>>
>> On Earth, the satellite's signal is BlueShifted by gravity
>> and RedShifted by its velocity,

It is _not_ written “BlueShifted” or “RedShifted”.

>> relative to earth's core.
> 
> While that is true,

In a manner of speaking.  Because gravity does not exist in general 
relativity, and the satellites’ velocity is measured relative to the ground 
receiver (approximately, in the ECI frame, which has nothing to do with 
“earth’s core” but with the *center* of the *geoid* through which the 
planet’s rotational axis passes).

That is, while the signal from a satellite to the ground will always be 
blueshifted due to a positive difference in spacetime curvature, the signal 
can *equally* be blueshifted due to relative motion of the satellite 
*towards* the observer or vice-versa.

> the relativistic correction

There are many misconceptions regarding GNSSs like GPS (we have discussed 
them all here in sci.physics.relativity).  What do *you* mean by 
“relativistic correction”?

> in GPS satellites is in the timebase,

What do you mean by “timebase”?

> not the transmission frequency.

Correct.  Both the gravitational redshift/blueshift and the relativistic 
Doppler shift are negligibly small here.


F’up2 sci.physics.relativity

PointedEars
-- 
Q: Where are offenders sentenced for light crimes?  
A: To a prism.

(from: WolframAlpha)

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#680791 — Re: GPS satellites.

On 4/9/18 10:28 PM, J. Clarke wrote:
> the relativistic correction in GPS satellites is
> in the timebase, not the transmission frequency.

Hmmmm. Your wording is ambiguous, and can be interpreted as either true or false.

The "timebase" of a GPS satellite is an atomic clock divided down to 
10.22999999543 MHz (this includes the primary relativistic corrections). The 
satellite's transmission frequencies are determined as integral multiples of 
that frequency. So the transmission frequencies have relativistic corrections 
included, but those corrections were applied to the timebase which determines them.

The result is that on the ground the L1 and L2 signals have frequencies 
1575.420000000 MHz and 1227.600000000 MHz, because they were transmitted from 
the satellite at slightly lower frequencies (as measured on the satellite).

Tom Roberts

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#680819 — Re: GPS satellites.

On Wed, 11 Apr 2018 14:36:27 -0500, Tom Roberts
<tjroberts137@sbcglobal.net> wrote:

>On 4/9/18 10:28 PM, J. Clarke wrote:
>> the relativistic correction in GPS satellites is
>> in the timebase, not the transmission frequency.
>
>Hmmmm. Your wording is ambiguous, and can be interpreted as either true or false.
>
>The "timebase" of a GPS satellite is an atomic clock divided down to 
>10.22999999543 MHz (this includes the primary relativistic corrections). The 
>satellite's transmission frequencies are determined as integral multiples of 
>that frequency. So the transmission frequencies have relativistic corrections 
>included, but those corrections were applied to the timebase which determines them.
>
>The result is that on the ground the L1 and L2 signals have frequencies 
>1575.420000000 MHz and 1227.600000000 MHz, because they were transmitted from 
>the satellite at slightly lower frequencies (as measured on the satellite).

The frequencies are carriers, their being off a fraction makes no
difference in the functioning of the system.  The timing is what makes
the system work.

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#680820 — Re: GPS satellites.

J.  Clarke wrote:
^^
Your first name belongs there.

> The frequencies are carriers,

I beg your pardon?

> their being off a fraction makes no difference in the functioning of the
> system. 

Correct.  Fortunately, nobody said or implied otherwise.

> The timing is what makes the system work.
      ^^^^^^
Again you are using words in an uncommon way.  How do *you* define “timing” 
here?  More to the point: How do *you* think does GPS work?

And with your reply, *please* do not crosspost to 4 newsgroups (without 
Followup-To) *again*.  TIA.


F’up2 sci.physics.relativity

PointedEars
-- 
Heisenberg is out for a drive when he's stopped by a traffic cop. 
The officer asks him "Do you know how fast you were going?" 
Heisenberg replies "No, but I know where I am."
(from: WolframAlpha)

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#680459

On Monday, April 9, 2018 at 11:05:00 AM UTC-4, Keith Stein wrote:
> On 09/04/2018 15:39, Tom Roberts wrote:
> > On 4/8/18 2:02 PM, Keith Stein wrote:
> >> The speed of light in vacuum is a silly concept,
> >> because what can this speed be relative to ?
> > 
> > Like ALL speeds, it is relative to the coordinates used to measure it.
> 
> :)  What is 'silly' Mr.Roberts is to believe that the velocity of any 
> given light beam could possibly be the same value 'c' relative to all 
> inertial coordinates, irrespective of how those coordinates are moving 
> relative to each other.

What is truly silly is calling this a belief.
In actuality this is an accepted observation of how the universe works.
And it is easy for you to change this observation. Simply provide
and experiment of light (or anything) traveling faster than c (SOLIV).

Good luck with that.
  Ed

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#680490

On 4/9/18 10:04 AM, Keith Stein wrote:
> On 09/04/2018 15:39, Tom Roberts wrote:
>> On 4/8/18 2:02 PM, Keith Stein wrote:
>>> The speed of light in vacuum is a silly concept,
>>> because what can this speed be relative to ?
>>
>> Like ALL speeds, it is relative to the coordinates used to measure it.
> 
> :)  What is 'silly' Mr.Roberts is to believe that the velocity of any given 
> light beam could possibly be the same value 'c' relative to all inertial 
> coordinates, irrespective of how those coordinates are moving relative to each 
> other.

No. What is truly SILLY (and STUPID) is you thinking that your GUESSES are 
better and more important than actual experiments.

Nature does what she does, regardless of whether that seems "silly" to some 
ill-informed humans like yourself.

Moreover, this is not really "silly" at all, it is just that you are IGNORANT: 
Special Relativity explicitly showed how it is possible, and actual experiments 
have confirmed it is indeed how nature behaves.

	Basically you are claiming "I, Keith Stein, am smarter and
	more knowledgeable about physics than every physicist of
	the past century." -- THAT is indeed SILLY (and STUPID).

Tom Roberts

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#680495

Keith Stein <keithstein111@gmail.com> wrote:
> On 09/04/2018 15:39, Tom Roberts wrote:
>> On 4/8/18 2:02 PM, Keith Stein wrote:
>>> The speed of light in vacuum is a silly concept,
>>> because what can this speed be relative to ?
>> 
>> Like ALL speeds, it is relative to the coordinates used to measure it.
> 
> :)  What is 'silly' Mr.Roberts is to believe that the velocity of any 
> given light beam could possibly be the same value 'c' relative to all 
> inertial coordinates, irrespective of how those coordinates are moving 
> relative to each other.

Why is that silly? 
Please try to make some case for your statement, using argument rather than
gut instinct. You will very quickly land on the assumption you’re making,
which ends up being wrong. 

> 
>> By convention, physicists use locally inertial coordinates unless 
>> otherwise specified. Around here that convention is not so well 
>> established (mostly because many people don't understand the need for it).
>> 
>> Tom Roberts
>> 
> 
> 



-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#680555

On Mon, 9 Apr 2018 16:04:59 +0100, Keith Stein wrote:

> What is 'silly' Mr.Roberts is to believe that the velocity of any
> given light beam could possibly be the same value 'c' relative to all
> inertial coordinates, irrespective of how those coordinates are moving
> relative to each other.

What is silly about it?  Weird, maybe, but "silly"?

It is, after all, a central tenet of a mathematical model of our world
which provides useful predictions of how that world will behave under
all but the most extreme of circumstances.  Some people who post here
use that model every day of their professional lives.

One wonders why you feel compelled to attack the notion.

This is like so many people I meet who look right at something, in front
of them and staring them in the face, and say, "But... that can't be!"

Stupid of me to ask, but I'm curious and have a few moments free: What's
the problem?  Do you find it aesthetically displeasing?  What?

-- 
Goat

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