The Speeed of Light

[The Starmaker]

It is not a question that nothing travels faster
than the speed of light...but

why nothing travels faster than the speed of light, or..

what is the function of light to have to travel faster than anything else.


The function, or reason why light travels so fast is because...

if you plan to travel into the future before anybody else gets there..

light needs to get there first so that there is a future to be there when you get there.

[Siri Cruise]

Post by The Starmaker
It is not a question that nothing travels faster
than the speed of light...but
why nothing travels faster than the speed of light, or..
what is the function of light to have to travel faster than anything else.
The function, or reason why light travels so fast is because...
if you plan to travel into the future before anybody else gets there..
light needs to get there first so that there is a future to be there when you get there.

So light is anti-langoliers pooping out the future before we arrive?

No, wait, now I get. Langoliers are klein bottles with their mouths in the past
and their poopholes in the future. They are constantly eating past time,
refurbishing it, and pooping it out as future time. The universe is just the
three dimensional surface of the four dimensional klein bottles.

It makes so much sense now.

[SolomonW]

Post by The Starmaker
It is not a question that nothing travels faster
than the speed of light...but
why nothing travels faster than the speed of light, or..
what is the function of light to have to travel faster than anything else.
The function, or reason why light travels so fast is because...
if you plan to travel into the future before anybody else gets there..
light needs to get there first so that there is a future to be there when you get there.

Not really.


Its not actually a requirement of modern physics that nothing goes faster
then light, what relativity does forbid is that ordinary matter can ever
reach the speed of light, because it would require infinite energy but this
theory does not rule out “tachyons” that can only travel faster than light.

The problem is that relativity has that if information can go faster then
light then *Causality* is lost.

[Tom Roberts]

[... much silliness and nonsense]

There are two quite different meanings of the symbol "c" [#], which have
confused you (and myriad other newbies and wannabes).

* c(1) is the speed that appears in the Lorentz transform.

* c(2) is the vacuum speed of light.

Note that c(1) is the limiting speed for timelike (massive) objects, not
c(2) as you seem to think. c(1) is locally invariant, and is the only
speed at which massless objects can travel.

At present, to the best of our knowledge c(1) = c(2); the limit on the
mass of photons is extremely small, but is not zero. This numerical
equality seems to be rather a coincidence, as these two meanings are
QUITE different. If it should happen that photons are not actually
massless, then c(1) != c(2) and lots of physics books would have to be
re-written. Folks like you would no longer get confused by this
particular subtlety (but of course many others remain).

[#] Due to the historical accident of Einstein using
electrodynamics to discover Special Relativity, while
logically their relationship is the other way 'round:
SR is geometry, which is much more fundamental and
pervasive than electrodynamics.

Tom Roberts

[Thomas 'PointedEars' Lahn]

[Next time, please set Followup-To when crossposting.]

Post by Tom Roberts
There are two quite different meanings of the symbol "c" [#], which have
confused you (and myriad other newbies and wannabes).
* c(1) is the speed that appears in the Lorentz transform.
* c(2) is the vacuum speed of light.
Note that c(1) is the limiting speed for timelike (massive) objects, not
c(2) as you seem to think. c(1) is locally invariant, and is the only
speed at which massless objects can travel.
At present, to the best of our knowledge c(1) = c(2); […]

Count me as one of the “newbies” then. This discussion brings me back to
my earlier question, which you had answered in an evasive, unsatisfactory
way back then. So I ask again:

Do you mean that, for example,

t' = γ (t − v∕c² x)

would have to be written precisely

t' = γ (t − v∕c₀² x)

*regardless* of the medium in which the relative motion occurs?

A simple “yes” or “no” will suffice for now. TIA.


PointedEars

[Alan Folmsbee]

Post by The Starmaker
It is not a question that nothing travels faster
than the speed of light...but
why nothing travels faster than the speed of light, or..
what is the function of light to have to travel faster than anything else.
The function, or reason why light travels so fast is because...
if you plan to travel into the future before anybody else gets there..
light needs to get there first so that there is a future to be there when you get there.

Light travels so fast because c is the speed that times grows with as
protons consume space and excrete time. Time departs matter radially
to balance the space arriving. Time grows at c, expanding the observable
universe.

[c***@optonline.net]

Speed of light for all observers
= constant c = 3E8 M/Sec .

Perceived wavelength when source is receding
is increased. i.e. red shift.

All in accordance with Einstein's Relativities.

[Keith Stein]

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

[Libor 'Poutnik' Stříž]

Post by Keith Stein
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.

Post by Keith Stein
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.

Post by Keith Stein
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.

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

The education experiment.

[Lofty Goat]

... The education experiment.

Many people should perform this experiment much more often.

[Edward Prochak]

Post by Keith Stein
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.

Post by Keith Stein
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

[Tom Roberts]

Post by Keith Stein
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

[Keith Stein]

Post by Tom Roberts

Post by Keith Stein
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.

Post by Tom Roberts
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

[Libor Striz]

Post by Keith Stein

Post by Tom Roberts

Post by Keith Stein
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.

[J***@.]

Post by Libor Striz
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.

[reber G=emc^2]

Post by J***@.

Post by Libor Striz
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

[hanson]

___"reber G=EMC^2"<***@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

[J. Clarke]

Post by J***@.

Post by Libor Striz
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.

[J***@.]

Post by J. Clarke

Post by J***@.
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.

[Thomas 'PointedEars' Lahn]

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

Post by J. Clarke

Post by J***@.
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”.

Post by J. Clarke

Post by J***@.
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.

Post by J. Clarke
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”?

Post by J. Clarke
in GPS satellites is in the timebase,

What do you mean by “timebase”?

Post by J. Clarke
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

[Tom Roberts]

Post by J. Clarke
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

[J. Clarke]

On Wed, 11 Apr 2018 14:36:27 -0500, Tom Roberts

Post by Tom Roberts

Post by J. Clarke
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.

[Thomas 'PointedEars' Lahn]

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

Post by J. Clarke
The frequencies are carriers,

I beg your pardon?

Post by J. Clarke
their being off a fraction makes no difference in the functioning of the
system.

Correct. Fortunately, nobody said or implied otherwise.

Post by J. Clarke
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

[Edward Prochak]

Post by Keith Stein

Post by Tom Roberts

Post by Keith Stein
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

[Tom Roberts]

Post by Tom Roberts

Post by Keith Stein
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

[Odd Bodkin]

Post by Keith Stein

Post by Tom Roberts

Post by Keith Stein
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.

Post by Keith Stein

Post by Tom Roberts
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

[Lofty Goat]

Post by Keith Stein
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?

[Keith Stein]

Post by Lofty Goat

Post by Keith Stein
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?

I find it weird certainly, also "silly" and "aesthetically displeasing"
too. What you should appreciate Goat is that if one goes back in time,
just 120 years, every competent physicist in the world would agree with
me. The simple truth is that it is i who am the conservative here, and
my message is simple "If it ain't broke don't fix it".

Einstein had probably not read, and certainly not understood Maxwell's
electro-magnetic theory. Maxwell insisted "A MEDIUM NECESSARY", and in
his 1905 paper Einstein drops the medium from Maxwell's equations,
(thereby making the derived velocity meaningless), and does not even
mention that he is making this (disastrous) modification to the theory.

There are many, many other things too, but i have enough experience to
know i'd be wasting my time to tell you about them eh!

keith stein

[Odd Bodkin]

Post by Keith Stein

Post by Lofty Goat

Post by Keith Stein
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?

I find it weird certainly, also "silly" and "aesthetically displeasing"
too. What you should appreciate Goat is that if one goes back in time,
just 120 years, every competent physicist in the world would agree with
me. The simple truth is that it is i who am the conservative here, and
my message is simple "If it ain't broke don't fix it".

Well, the problem is a little complicated in that for some applications,
classical physics is fine. This doesn’t mean it’s right, only that it’s
good enough for those cases. But what is true is that there are a lot of
applications for which classical physics definitely is broken. This is what
sparks the interest in asking, “well, if that’s not the right answer, then
what’s a better answer?” And against the tally sheet of measurements, there
is absolutely no question that relativity is a better answer. This isn’t a
matter of conservatism or aesthetics. It’s a brute force confrontation with
a long tally sheet of cold, objective facts. In the domain of science,
history or intuition or aesthetics take a distant back seat to that. Some
folks don’t care for that.

Post by Keith Stein
Einstein had probably not read, and certainly not understood Maxwell's
electro-magnetic theory. Maxwell insisted "A MEDIUM NECESSARY", and in
his 1905 paper Einstein drops the medium from Maxwell's equations,
(thereby making the derived velocity meaningless), and does not even
mention that he is making this (disastrous) modification to the theory.
There are many, many other things too, but i have enough experience to
know i'd be wasting my time to tell you about them eh!
keith stein

[Libor Striz]

Post by Keith Stein
[...]
just 120 years, every competent physicist in the world would agree with
me. The simple truth is that it is i who am the conservative here, and
my message is simple "If it ain't broke don't fix it".

The point is, the old classical theories were found broken even
before Einstein.

Since 1880s, physicists are fixing or replacing them to fit
observations, that were not known in Maxwell time.

[Lofty Goat]

On Tue, 10 Apr 2018 17:56:48 +0100, Keith Stein

Post by Keith Stein
I find it weird certainly, also "silly" and "aesthetically displeasing"
too. What you should appreciate Goat is that if one goes back in time,
just 120 years, every competent physicist in the world would agree with
me. The simple truth is that it is i who am the conservative here, and
my message is simple "If it ain't broke don't fix it".

Every theory is in that sense "broke".

Classical mechanics, on which the notions held by those competent
physicists are based, breaks down, as I mentioned, under circumstances
which just aren't that unusual these days, and was supplanted, no,
rather augmented, by relativity, which does give accurate and useful
answers under those circumstances.

Under conditions today regarded as extreme, such as in the very centers
of black holes or at a distance of 1E-60m from an electron, which should
be inside that "dimensionless" particle's event horizon, relativity
breaks down, giving us answers which are nonsense.

So some more detailed theory, which will provide the same answers as
relativity under now-normal circumstances and reasonable answers under
those now-extreme ones, will take its place. Classical mechanics will
remain a good approximation of the "true" theory, and relativity will
remain a better approximation, but the new one will be better still.

It's broke. All scientific theories are. So smart folks think about
it, conduct experiments, and fix it... then find ways i nwhich the new
theory is broke, so they then set about fixing that.

It's called scientific progress. It'll go on for a while yet.

It isn't "conservatism" to hold that such progress should end, it's
reactionary. Why? Because those competent physicists of yore, most of
them at least, expected it to proceed.

And hey, watching it beats the hell out of watching guys walk around a
pasture hitting a ball with a curved metal stick while some guy
off-camera mutters into a microphone. For me, at least.

[Keith Stein]

A more precise prediction for the clock in the ISS is
that it will loose 24.7 us per day.

EXCELLENT!
Now are you seriously trying to tell me that no one thought to take
a couple of clocks up to the ISS to demonstrate the 24.7 us/day ?
That is a HUGE AMOUNT !!! You could measure that with the ticker in
the computer you are sitting at now.
1. SYNCRHONISE TWO CLOCKS.
2. FLY ONE TO THE ISS.
3. NEXT FLIGHT UP TAKE UP THE OTHER.
4. COMPARE THE 2 CLOCKS ON THE ISS.
If you can demonstrate even half the 24.7 us/day you are admitting
I WOULD BE AMAZED !
Certainly it would be a lot more convincing than anything reported
in the many references you so kindly provided Mr.Anderson.
keith stein