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Why is the speed of light the same for all observers? (Inertial ones, at least)



 
 
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  #21  
Old November 4th 05 posted to sci.physics,sci.physics.relativity,sci.chem,sci.physics.particle,sci.math
brian a m stuckless
external usenet poster
 
Posts: 3,468
Default Why is the speed of light the same for all observers? (Inertial...

CORRECTiON: e=RESTmass*c^2=(mol part)*K*Volt*meter/c^2.

Volt*Amp*sec = GUESS EQUiVALENT iNTRiNSiC unit energy e

(mol part)*K*Volt*meter
= -- -- -- -- -- -- -- -- = (GUESS unit REST mass)*c^2.
c^2
Whe
GUESS iSS, TEST SHELL mass m1 = STANDARD TEST REST-mass,
at SUBMERGED weightlessness, in STANDARD AMBiENT medium:
m1 = mD - mS = N*u = {do - (mi / Vi)} = [mph]
= SHELL volume*density
= Vs*ds
= Vi*(do - di)
= (Po - Pi)*Vi*dx / Po
= 4*thick*S*Vi*dx / Po*(cavity dia + SHELL thickness)
= h*fL / c^2
= nA*{mph}*ls / rA
= mS / (n - 1)
= N / Nu
mD / n
= ni*u / xi
= Vdis*Ddis / n
= nA*hbar / rA*c
= iNTRiNSiC energy / c^2
= (mol part)*K*Volt*m / c^4 ..line CORRECTiON *m a meter.
brian a m stuckless


Bilge wrote: Daniel Weston, incompetent asshole:
"Why is the speed of light the same for all observers?"
Ans: No body knows.


Wrong. What nobody knows is how to get the answer through your
thick skull. That is an entirely different question.

That is the correct answer and it should be given quickly. Some
un professional defenders of relativity on this ng, become
incredibly defensive when asked this question or like questions
where the answer is unknown.


By their immature and canned responses,
you would think that somebody's ancestry had been called into
question.

It is not a crime to ask why, meaning by what mechanism.


No, but it is a crime to reject the answer because it doesn't
fit your naive world view.

It is not a crime to answer such questions with an honest and
simple, 'we don't know'.


No, but it is a crime to blame your inability to understand the
answer on all of those who gave you the answer you requested.



Ads
  #22  
Old November 4th 05 posted to sci.physics.relativity
Spoonfed
external usenet poster
 
Posts: 180
Default Why is the speed of light the same for all observers? (Inertial...

Dirk Van de moortel wrote:
"Spoonfed" wrote in message ups.com...


snip

Now, I don't quite see how this particular idea leads to a constant
speed of light, but it is a bit strange, anyway. I'm just bringing it
up because that's a question I've never fully explored.

I do remember sometime in college when I THOUGHT I understood how
electric and magnetic fields explained the speed of light. Multiplying
the permittivity times the permeability of free space yielded the speed
of light. However, I can't remember what would make a person multiply
these two values together, except that they happen to produce the speed
of light.

So, I guess the question I want to ask is, why do you multiply
permittivity and permeability together?


When you juggle with Maxwell's equations, they turn out
to produce standard wave equations that all have
epsilon_0 * mu_0 as a coefficient of the second order
partial time derivative term.
The standard wave equation has 1 / wave speed^2
as its coefficient at that place
http://mathworld.wolfram.com/WaveEquation.html

Dirk Vdm


Ahhh, yes...

I think I may have seen all the steps somewhere in my education, but I
never got around to putting them together in order. Rush, rush, rush.
I took Classical Electrodynamics after 10 years without even looking at
a differential equations problem, so unfortunately, most of it went
over my head.

Now, the wave equation refers to density, in the case of water waves or
sound waves, but it's a little more complicated in the case of light
waves, right?

Now I did a quick google image search for Maxwell's equations and found
this page: http://home.usit.net/~cmdaven/electro.htm by Clyde
Davenport. He shows some equations out of Jackson, but doesn't define
A here.

Ahhh, here it is, in section 6.2 of Jackson. He defines the vector
potential, A and the scalar potential, Phi in terms of the magnetic and
electric field, and ends up with two equations that look just like the
wave equation, except with sources due to charge density and current
density.

I begin to see a route, though it does look harrrrrd. Jackson's
explanation takes up less than two pages, which probably means about
ten or twenty pages of "WTF?" for me.

  #23  
Old November 4th 05 posted to sci.physics.relativity
Spoonfed
external usenet poster
 
Posts: 180
Default Why is the speed of light the same for all observers? (Inertial...



Sue... wrote:
Spoonfed wrote:
Sue... wrote:
Daniel Weston wrote:
"Why is the speed of light the same for all observers?" Ans: No body
knows.

Students of electromagnetism know...or think they know:
http://www.conformity.com/0102reflectionsfig3.gif from:
http://www.conformity.com/0102reflections.html

http://physics.nist.gov/cuu/Images/alphaeq.gif from:
http://physics.nist.gov/cuu/Constants/alpha.html

But the study of electromagnetism is
uh...harrrrd.... ya hafta be workin' harrrd ;-)


Seems like the right direction... But all that hard stuff is pretty
confusing. Do you suppose we could find some explanation that may not
be so hard? Maybe not a timeline but at least a list of goals, and
maybe a roadmap to understanding?


Goals?
1. Learn below 30 GHz
2. Learn above 30 GHz

Two steps because, when the antenna is built out of
oscillators things get tricker... but the same rules
apply.


Okay, start with a stationary charged particle. It has a central
electric field. If that particle is moving, if I am not mistaken, it
creates a magnetic field. However, somebody moving along with the
particle doesn't see the magnetic field.


Start with two particles. + and -
Move one in the real world filled with + and -.
It is harder but the integral form is 'timeless'
(pun intended)
http://en.wikipedia.org/wiki/Multiple_integral

Now, I don't quite see how this particular idea leads to a constant
speed of light, but it is a bit strange, anyway. I'm just bringing it
up because that's a question I've never fully explored.


http://physics.nist.gov/cuu/Images/alphaeq.gif from:
http://physics.nist.gov/cuu/Constants/alpha.html

The mass of a charge pair (0.511 MeV) is like the
mass of a guitar string. The Coulomb force is
like the tension on the guitar string.
AFAIK... no relation to m therory. LOL


I do remember sometime in college when I THOUGHT I understood how
electric and magnetic fields explained the speed of light. Multiplying
the permittivity times the permeability of free space yielded the speed
of light. However, I can't remember what would make a person multiply
these two values together, except that they happen to produce the speed
of light.


Substitute "homogenous universe" (377 ohms) for free space and it is
easier to see. Permeability we associate with spinning. So we have
to be near some thing spinning. See:

http://www.conformity.com/0102reflectionsfig3.gif from:
http://www.conformity.com/0102reflections.html



So, I guess the question I want to ask is, why do you multiply
permittivity and permeability together?

As you are closer to matter the spinning magnetic domains
predominate as an energy storage element. When you are
farther from matter, the inertia of the charge pair predominates.

Because both eps and mu both represent storage, and thus
delay, they can be normalized and combined for the SOL
formula.

Also you have to careful about cgs, MKS and SI differences
as you calculate with dielectrics.
http://scienceworld.wolfram.com/phys...ptibility.html

Sue...


Sue,

I know very little particle physics, and I I am a bit troubled that
this explanation to why the speed of light is constant *appears* so
much different from the explanation which seems to make sense.

Is this explanation the same as the explanation that Dirk has given,
only approaching it from another direction, or is this an alternative
explanation? Regardless, I cannot detect any contextual relationship
between your statements mine throughout your response.

If you would care to start over, please clarify what I am saying or
asking if you don't know, use no abbreviations and connect the dots
very carefully, since I have no background in particle physics.

Thanks,
Jonathan Doolin

  #24  
Old November 4th 05 posted to sci.physics.relativity
Dirk Van de moortel
external usenet poster
 
Posts: 15,355
Default Why is the speed of light the same for all observers? (Inertial...


"Spoonfed" wrote in message oups.com...
Dirk Van de moortel wrote:
"Spoonfed" wrote in message

ups.com...

snip

Now, I don't quite see how this particular idea leads to a constant
speed of light, but it is a bit strange, anyway. I'm just bringing it
up because that's a question I've never fully explored.

I do remember sometime in college when I THOUGHT I understood how
electric and magnetic fields explained the speed of light. Multiplying
the permittivity times the permeability of free space yielded the speed
of light. However, I can't remember what would make a person multiply
these two values together, except that they happen to produce the speed
of light.

So, I guess the question I want to ask is, why do you multiply
permittivity and permeability together?


When you juggle with Maxwell's equations, they turn out
to produce standard wave equations that all have
epsilon_0 * mu_0 as a coefficient of the second order
partial time derivative term.
The standard wave equation has 1 / wave speed^2
as its coefficient at that place
http://mathworld.wolfram.com/WaveEquation.html

Dirk Vdm


Ahhh, yes...

I think I may have seen all the steps somewhere in my education, but I
never got around to putting them together in order. Rush, rush, rush.
I took Classical Electrodynamics after 10 years without even looking at
a differential equations problem, so unfortunately, most of it went
over my head.

Now, the wave equation refers to density, in the case of water waves or
sound waves, but it's a little more complicated in the case of light
waves, right?


Essentially it's always the same form
\/^2 F = 1/v^2 @^2F/@t^2
where \/^2 is the Laplacian and @/@t partial time derivative.
See
http://mathworld.wolfram.com/WaveEquation.html


Now I did a quick google image search for Maxwell's equations and found
this page: http://home.usit.net/~cmdaven/electro.htm by Clyde
Davenport. He shows some equations out of Jackson, but doesn't define
A here.

Ahhh, here it is, in section 6.2 of Jackson. He defines the vector
potential, A and the scalar potential, Phi in terms of the magnetic and
electric field, and ends up with two equations that look just like the
wave equation, except with sources due to charge density and current
density.

I begin to see a route, though it does look harrrrrd. Jackson's
explanation takes up less than two pages, which probably means about
ten or twenty pages of "WTF?" for me.


I don't have Jackson.
It's seems rather well spelled out in Bo Thide's
http://www.plasma.uu.se/CED/Book/index.html#top
Download the pdf and have a look at chapter 2.

You'll have to search for Maxwell's equations where epsilon_0
and mu_0 are used. For instance in the Wikipedia
http://en.wikipedia.org/wiki/Maxwell's_equations
under the header "In vacuum, without charges or currents".
Enjoy puzzling like I did some .... oops ... 28 years ago now :-)

Dirk Vdm



  #25  
Old November 4th 05 posted to sci.physics.relativity
Sue...
external usenet poster
 
Posts: 9,168
Default Why is the speed of light the same for all observers? (Inertial...


Spoonfed wrote:
Sue... wrote:
Spoonfed wrote:
Sue... wrote:
Daniel Weston wrote:
"Why is the speed of light the same for all observers?" Ans: No body
knows.

Students of electromagnetism know...or think they know:
http://www.conformity.com/0102reflectionsfig3.gif from:
http://www.conformity.com/0102reflections.html

http://physics.nist.gov/cuu/Images/alphaeq.gif from:
http://physics.nist.gov/cuu/Constants/alpha.html

But the study of electromagnetism is
uh...harrrrd.... ya hafta be workin' harrrd ;-)

Seems like the right direction... But all that hard stuff is pretty
confusing. Do you suppose we could find some explanation that may not
be so hard? Maybe not a timeline but at least a list of goals, and
maybe a roadmap to understanding?


Goals?
1. Learn below 30 GHz
2. Learn above 30 GHz

Two steps because, when the antenna is built out of
oscillators things get tricker... but the same rules
apply.


Okay, start with a stationary charged particle. It has a central
electric field. If that particle is moving, if I am not mistaken, it
creates a magnetic field. However, somebody moving along with the
particle doesn't see the magnetic field.


Start with two particles. + and -
Move one in the real world filled with + and -.
It is harder but the integral form is 'timeless'
(pun intended)
http://en.wikipedia.org/wiki/Multiple_integral

Now, I don't quite see how this particular idea leads to a constant
speed of light, but it is a bit strange, anyway. I'm just bringing it
up because that's a question I've never fully explored.


http://physics.nist.gov/cuu/Images/alphaeq.gif from:
http://physics.nist.gov/cuu/Constants/alpha.html

The mass of a charge pair (0.511 MeV) is like the
mass of a guitar string. The Coulomb force is
like the tension on the guitar string.
AFAIK... no relation to m therory. LOL


I do remember sometime in college when I THOUGHT I understood how
electric and magnetic fields explained the speed of light. Multiplying
the permittivity times the permeability of free space yielded the speed
of light. However, I can't remember what would make a person multiply
these two values together, except that they happen to produce the speed
of light.


Substitute "homogenous universe" (377 ohms) for free space and it is
easier to see. Permeability we associate with spinning. So we have
to be near some thing spinning. See:

http://www.conformity.com/0102reflectionsfig3.gif from:
http://www.conformity.com/0102reflections.html



So, I guess the question I want to ask is, why do you multiply
permittivity and permeability together?

As you are closer to matter the spinning magnetic domains
predominate as an energy storage element. When you are
farther from matter, the inertia of the charge pair predominates.

Because both eps and mu both represent storage, and thus
delay, they can be normalized and combined for the SOL
formula.

Also you have to careful about cgs, MKS and SI differences
as you calculate with dielectrics.
http://scienceworld.wolfram.com/phys...ptibility.html

Sue...


Sue,

I know very little particle physics, and I I am a bit troubled that
this explanation to why the speed of light is constant *appears* so
much different from the explanation which seems to make sense.


The relation from NIST doesn't make sense ?


Is this explanation the same as the explanation that Dirk has given,
only approaching it from another direction, or is this an alternative
explanation? Regardless, I cannot detect any contextual relationship
between your statements mine throughout your response.


You consider his delusions about my identity are an explanation for
SOL?


If you would care to start over, please clarify what I am saying or
asking if you don't know, use no abbreviations and connect the dots
very carefully, since I have no background in particle physics.


You don't need particle physics except knowing that charges have
constant mass.
Surely you don't think that particles are what causes a charged comb
to attract a pith ball ?

Starting over:
Click on Electrostatics at top of page and work
through to Light chapter.
The pdf files are big but have lots of illustrations.
http://web.mit.edu/8.02t/www/802TEAL3D/teal_tour.htm

Here is Maxwells equations from PoV you never imagined.
http://arxiv.org/abs/physics/0204034

Sue...





Thanks,
Jonathan Doolin


  #26  
Old November 5th 05 posted to sci.physics,sci.physics.relativity,alt.asshole-factory
Mahmoud In My Dinner Jacket
external usenet poster
 
Posts: 450
Default Why is the speed of light the same for all observers? (Inertial...

Bilge wrote:
Daniel Weston, incompetent asshole:
"Why is the speed of light the same for all observers?" Ans: No body
knows.


Wrong. What nobody knows is how to get the answer through your
thick skull. That is an entirely different question.

That is the correct answer and it should be given quickly. Some
un professional defenders of relativity on this ng, become incredibly
defensive when asked this question or like questions where the answer is
unknown.


By their immature and canned responses,
you would think that somebody's ancestry had been called into question.

It is not a crime to ask why, meaning by what mechanism.


No, but it is a crime to reject the answer because it doesn't fit
your naive world view.


It is precisely by asking naive questions that Einstein was able to
give not-in-the-least-naive answers.


alt.asshole-factory --- good Lord, IS there such a group??

  #28  
Old November 5th 05 posted to sci.physics.relativity
Mahmoud In My Dinner Jacket
external usenet poster
 
Posts: 450
Default Why is the speed of light the same for all observers? (Inertial...


jem wrote:
Daniel Weston wrote:
"Why is the speed of light the same for all observers?" Ans: No body
knows. That is the correct answer and it should be given quickly. Some
un professional defenders of relativity on this ng, become incredibly
defensive when asked this question or like questions where the answer is
unknown.
By their immature and canned responses,
you would think that somebody's ancestry had been called into question.

It is not a crime to ask why, meaning by what mechanism. It is not a
crime to answer such questions with an honest and simple, 'we don't
know'.


According to Relativity, the speed of light *isn't* the same for all
observers.

When measuured locally, or within Inertial reference frames, the speed
of light in vacuum is constant because in 1983 the meter was redefined
in such a way as to make it constant.

Want the answer to a related question, like "Why does Nature have a
speed limit?"? Well, suppose it didn't have one. Think about how you'd
answer the question "Why doesn't Nature have a speed limit?".


In that case, I'd like to see the smartass who thought up THAT
question!!

Fancy free, so to speak.

  #29  
Old November 6th 05 posted to sci.physics,sci.physics.relativity,alt.asshole-factory
Bilge
external usenet poster
 
Posts: 13,439
Default Why is the speed of light the same for all observers? (Inertial...

Mahmoud In My Dinner Jacket:
Bilge wrote:
Daniel Weston, incompetent asshole:
"Why is the speed of light the same for all observers?" Ans: No body
knows.


Wrong. What nobody knows is how to get the answer through your
thick skull. That is an entirely different question.

That is the correct answer and it should be given quickly. Some
un professional defenders of relativity on this ng, become incredibly
defensive when asked this question or like questions where the answer is
unknown.


By their immature and canned responses,
you would think that somebody's ancestry had been called into question.

It is not a crime to ask why, meaning by what mechanism.


No, but it is a crime to reject the answer because it doesn't fit
your naive world view.


It is precisely by asking naive questions that Einstein was able to
give not-in-the-least-naive answers.


To compare and contrast your scenario with the case at hand, note
that einstein spent at least a few hours trying to understand his
question from a physical perspective and then answer it. On the
other hand, mr. weston has been posting the same criticisms for years
for the simple reason that he doesn't want to spend a few hours trying
understand the answers he's been given from a wide variety of perspectives
by a number of people who attempted to find some means of getting the
point across. What stands in the way of mr. weston receiving the answer
to the question he asked, is mr. weston, who will apparently not accept
_any_ answer that is consistent with relativity.

Ignorance due to lack of knowledge can be cured. A dedicated
effort to remain ignorant in spite of having every opportunity
to remedy the lack of knowledge, cannot, and mr. weston is about
as dedicated as it gets.

alt.asshole-factory --- good Lord, IS there such a group??


Believe it or not. Out of 40,000+ newsgroups, just imagine what
else is out there.

 




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