Groups > sci.physics > #577709 > unrolled thread

Does anyone really know the physical cause for time dilation and length contraction?

Started by	xxein1@att.net
First post	2016-05-13 12:17 -0700
Last post	2016-05-16 13:20 +0200
Articles	20 on this page of 278 — 21 participants

Back to article view | Back to sci.physics

Page 12 of 14 — ← Prev page 1 … 10 11 [12] 13 14 Next page →

#579208

From	Nicolaas Vroom <nicolaas.vroom@pandora.be>
Date	2016-05-20 04:00 -0700
Message-ID	<21decc40-dbc0-4d07-8131-a2714fcd6c52@googlegroups.com>
In reply to	#578978

Op donderdag 19 mei 2016 19:04:08 UTC+2 schreef Odd Bodkin:
> On 5/19/2016 11:03 AM, Nicolaas Vroom wrote:

> >>> The link:
> >>> http://www.aps.anl.gov/About/APS_Overview/linac.html
> >>> tells you that c = 299792458 m/sec but not how this speed is measured.
> >>> When I read the text, what they measure is the speed of electrons.
> >>
> >> That's because you're not reading about the part of the accelerator
> >> where the photons are in flight. Good grief.
> >
> > Why do n't you supply me with a link that gives the details?
> 
> Because I cater to neither your laziness or your incompetence at doing 
> library research. This is a basic skill that needs to be learned through 
> practice.

It is always good to read a honest review.
The problem is I have tried to find more background information related
to your text. But I think I failed. 
I used for google search:
"advanced photon source argonne national laboratory wiggler magnets"
I hope that also other readers are interested in the details
so please give me better "google search" details.

> >> Nicolaas, this is naive at best. Physicists have the obligation to
> >> answer questions if they have taken the job of teaching a class and the
> >> people asking the question have paid tuition to take that class.
> >
> > Sorry, I do not think that physicists only answer questions when they 
> > have a teaching job. It sounds narrow minded.
> 
> Well you tell me how well reality meets your expectations.

My expectations are zero.
The reality is completely outside my imagination.
Around 1970 we had IBM and the seven dwarfs but no internet and all? 
knowledge came from our local library.
Around 1995 I owned my first Pc and we had Internet.
Now we have https://arxiv.org/ with millions of free state of the art 
documents. What is so good at the end of each document there are links to 
other documents which allow you to get more background information and 
which keep me busy for the rest of my life.
The same for Wikipedia as start-up toolkit.

Enjoy.

Nicolaas Vroom
http://users.pandora.be/nicvroom/

[toc] | [prev] | [next] | [standalone]

#579265

From	Odd Bodkin <bodkinodd@gmail.com>
Date	2016-05-20 11:54 -0500
Message-ID	<nhnfgf$5ce$1@gioia.aioe.org>
In reply to	#579208

On 5/20/2016 6:00 AM, Nicolaas Vroom wrote:
> Op donderdag 19 mei 2016 19:04:08 UTC+2 schreef Odd Bodkin:
>> On 5/19/2016 11:03 AM, Nicolaas Vroom wrote:
>
>>>>> The link:
>>>>> http://www.aps.anl.gov/About/APS_Overview/linac.html
>>>>> tells you that c = 299792458 m/sec but not how this speed is measured.
>>>>> When I read the text, what they measure is the speed of electrons.
>>>>
>>>> That's because you're not reading about the part of the accelerator
>>>> where the photons are in flight. Good grief.
>>>
>>> Why do n't you supply me with a link that gives the details?
>>
>> Because I cater to neither your laziness or your incompetence at doing
>> library research. This is a basic skill that needs to be learned through
>> practice.
>
> It is always good to read a honest review.
> The problem is I have tried to find more background information related
> to your text. But I think I failed.

Yes, I think you did.

> I used for google search:
> "advanced photon source argonne national laboratory wiggler magnets"

Did you refine your search after that, or did you just try this and give 
up? When you go to the library, do you open up the first book that pull 
down from the shelf, and if the answer is not in it, you give up?

> I hope that also other readers are interested in the details
> so please give me better "google search" details.

Try doing a search in arxiv.org or a better Google search tool: 
http://scholar.google.com.


>
>>>> Nicolaas, this is naive at best. Physicists have the obligation to
>>>> answer questions if they have taken the job of teaching a class and the
>>>> people asking the question have paid tuition to take that class.
>>>
>>> Sorry, I do not think that physicists only answer questions when they
>>> have a teaching job. It sounds narrow minded.
>>
>> Well you tell me how well reality meets your expectations.
>
> My expectations are zero.
> The reality is completely outside my imagination.
> Around 1970 we had IBM and the seven dwarfs but no internet and all?
> knowledge came from our local library.

Which is still available.

> Around 1995 I owned my first Pc and we had Internet.
> Now we have https://arxiv.org/ with millions of free state of the art
> documents.

And so why did you do an ordinary Google search to learn about the APS, 
and why did you only look at overview web pages? Why did you not look 
for papers about APS on arxiv.org?

> What is so good at the end of each document there are links to
> other documents which allow you to get more background information and
> which keep me busy for the rest of my life.
> The same for Wikipedia as start-up toolkit.
>
> Enjoy.
>
> Nicolaas Vroom
> http://users.pandora.be/nicvroom/
>


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

[toc] | [prev] | [next] | [standalone]

#578483

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-16 18:57 -0500
Message-ID	<gZqdnTtbmsbHw6fKnZ2dnUU7-SOdnZ2d@giganews.com>
In reply to	#578413

On 5/16/16 2:17 PM, jay moseley wrote:
> Speed is not measured. Only assumed.


   In astronomy and physics speed is often measure by Doppler shift.
   For example Doppler can be used to measure the earth's orbital
   velocity, the sun's rotation, the speed of a speeding car, the
   recession speed of a distant supernova explosion, and the velocity
   of the ejecta from from that supernova.

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578502

From	kenseto <setoken@att.net>
Date	2016-05-16 19:53 -0700
Message-ID	<9c709edf-e537-4a9e-a894-54218d95b34b@googlegroups.com>
In reply to	#578483

On Monday, May 16, 2016 at 7:57:17 PM UTC-4, Sam Wormley wrote:
> On 5/16/16 2:17 PM, jay moseley wrote:
> > Speed is not measured. Only assumed.
> 
> 
>    In astronomy and physics speed is often measure by Doppler shift.
>    For example Doppler can be used to measure the earth's orbital
>    velocity, the sun's rotation, the speed of a speeding car, the
>    recession speed of a distant supernova explosion, and the velocity
>    of the ejecta from from that supernova.

So why don't they use Doppler shift to measure the speed of incoming light???

[toc] | [prev] | [next] | [standalone]

#578559

From	Odd Bodkin <bodkinodd@gmail.com>
Date	2016-05-17 07:14 -0500
Message-ID	<nhf1uf$1lc0$3@gioia.aioe.org>
In reply to	#578502

On 5/16/2016 9:53 PM, kenseto wrote:
> On Monday, May 16, 2016 at 7:57:17 PM UTC-4, Sam Wormley wrote:
>> On 5/16/16 2:17 PM, jay moseley wrote:
>>> Speed is not measured. Only assumed.
>>
>>
>>    In astronomy and physics speed is often measure by Doppler shift.
>>    For example Doppler can be used to measure the earth's orbital
>>    velocity, the sun's rotation, the speed of a speeding car, the
>>    recession speed of a distant supernova explosion, and the velocity
>>    of the ejecta from from that supernova.
>
> So why don't they use Doppler shift to measure the speed of incoming light???
>

Because you can bounce light off a speeding car, but you can't bounce 
light off light. Duh, Ken.

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

[toc] | [prev] | [next] | [standalone]

#578583

From	kenseto <setoken@att.net>
Date	2016-05-17 06:50 -0700
Message-ID	<9a111bfd-5a80-47fd-b027-14568bc49e5d@googlegroups.com>
In reply to	#578559

On Tuesday, May 17, 2016 at 8:14:12 AM UTC-4, Odd Bodkin wrote:
> On 5/16/2016 9:53 PM, kenseto wrote:
> > On Monday, May 16, 2016 at 7:57:17 PM UTC-4, Sam Wormley wrote:
> >> On 5/16/16 2:17 PM, jay moseley wrote:
> >>> Speed is not measured. Only assumed.
> >>
> >>
> >>    In astronomy and physics speed is often measure by Doppler shift.
> >>    For example Doppler can be used to measure the earth's orbital
> >>    velocity, the sun's rotation, the speed of a speeding car, the
> >>    recession speed of a distant supernova explosion, and the velocity
> >>    of the ejecta from from that supernova.
> >
> > So why don't they use Doppler shift to measure the speed of incoming light???
> >
> 
> Because you can bounce light off a speeding car, but you can't bounce 
> light off light. Duh, Ken.

Incoming light is Doppler shifted. Therefore it can be used to determine the speed of incoming light as follows:
c'=(c)(Frequency of the rest frame of the source/incoming frequency of the source.)

duh....

[toc] | [prev] | [next] | [standalone]

#578591

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-17 09:22 -0500
Message-ID	<Btqdnb3136S5tKbKnZ2dnUU7-U-dnZ2d@giganews.com>
In reply to	#578583

On 5/17/16 8:50 AM, kenseto wrote:
> Incoming light is Doppler shifted. Therefore it can be used to determine the speed of incoming light as follows:
> c'=(c)(Frequency of the rest frame of the source/incoming frequency of the source.)

   Ah Seto, you don't understand that Doppler Effect is used to measure
   the *relative velocity between the source and observer* . *The speed*
   *of light is a finite constant* .

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578788

From	kenseto <setoken@att.net>
Date	2016-05-18 07:24 -0700
Message-ID	<73b9fcb3-6a2f-4090-a54e-74707f52fe49@googlegroups.com>
In reply to	#578591

On Tuesday, May 17, 2016 at 10:22:31 AM UTC-4, Sam Wormley wrote:
> On 5/17/16 8:50 AM, kenseto wrote:
> > Incoming light is Doppler shifted. Therefore it can be used to determine the speed of incoming light as follows:
> > c'=(c)(Frequency of the rest frame of the source/incoming frequency of the source.)
> 
> 
> 
>    Ah Seto, you don't understand that Doppler Effect is used to measure
>    the *relative velocity between the source and observer* . *The speed*
>    *of light is a finite constant* .

It is you who don't understand Doppler effect. It can be used to measure relative velocity of all objects including light.

[toc] | [prev] | [next] | [standalone]

#578790

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-18 09:57 -0500
Message-ID	<7cKdnTflDah9H6HKnZ2dnUU7-e-dnZ2d@giganews.com>
In reply to	#578788

On 5/18/16 9:24 AM, kenseto wrote:
> It is you who don't understand Doppler effect. It can be used to measure relative velocity of all objects including light.


   Wrong again, Seto.

   Seto, you don't understand that Doppler Effect is used to measure
   the *relative velocity between the source and observer* . *The speed*
   *of light is a finite constant* .

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578593

From	moroney@world.std.spaamtrap.com (Michael Moroney)
Date	2016-05-17 14:31 +0000
Message-ID	<nhf9vm$l5n$1@pcls7.std.com>
In reply to	#578583

kenseto <setoken@att.net> writes:

>On Tuesday, May 17, 2016 at 8:14:12 AM UTC-4, Odd Bodkin wrote:
>> On 5/16/2016 9:53 PM, kenseto wrote:
>> >
>> > So why don't they use Doppler shift to measure the speed of incoming light???
>> >
>> 
>> Because you can bounce light off a speeding car, but you can't bounce 
>> light off light. Duh, Ken.

>Incoming light is Doppler shifted. Therefore it can be used to determine 
>the speed of incoming light as follows:
>c'=(c)(Frequency of the rest frame of the source/incoming frequency of the 
>source.)

But that is incorrect because it makes the implicit incorrect assumption the
wavelength remains the same.  As diffraction grating type detectors depend
on the wavelength not the frequency to work, we already know that is
incorrect.

[toc] | [prev] | [next] | [standalone]

#578784

From	kenseto <setoken@att.net>
Date	2016-05-18 06:56 -0700
Message-ID	<6b590f78-33ce-4610-b885-761c575e3453@googlegroups.com>
In reply to	#578593

On Tuesday, May 17, 2016 at 10:31:56 AM UTC-4, Michael Moroney wrote:
> kenseto <setoken@att.net> writes:
> 
> >On Tuesday, May 17, 2016 at 8:14:12 AM UTC-4, Odd Bodkin wrote:
> >> On 5/16/2016 9:53 PM, kenseto wrote:
> >> >
> >> > So why don't they use Doppler shift to measure the speed of incoming light???
> >> >
> >> 
> >> Because you can bounce light off a speeding car, but you can't bounce 
> >> light off light. Duh, Ken.
> 
> >Incoming light is Doppler shifted. Therefore it can be used to determine 
> >the speed of incoming light as follows:
> >c'=(c)(Frequency of the rest frame of the source/incoming frequency of the 
> >source.)
> 
> But that is incorrect because it makes the implicit incorrect assumption the
> wavelength remains the same. 

That's not an incorrect assumption. The incoming light becomes a new light source in the observer's frame and the grating defines a new wave length for this new light source. The incoming speed must be calculated using the original wavelength of the source.
This new light source just like any other light source in the observer's frame....and its speed is c like all the other light sources in the observer's frame.

> As diffraction grating type detectors depend
> on the wavelength not the frequency to work, we already know that is
> incorrect.

[toc] | [prev] | [next] | [standalone]

#578792

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-18 10:02 -0500
Message-ID	<7cKdnTHlDaiSGaHKnZ2dnUU7-e8AAAAA@giganews.com>
In reply to	#578784

On 5/18/16 8:56 AM, kenseto wrote:
> The incoming light becomes a new light source in the observer's frame and the grating defines a new wave length for this new light source.



   No, Seto, not only are you confused about the propagation of light,
   but also the concept of reference frames. Either of which prevents
   you from understanding relativity.


-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578800

From	moroney@world.std.spaamtrap.com (Michael Moroney)
Date	2016-05-18 15:30 +0000
Message-ID	<nhi1qb$3ab$1@pcls7.std.com>
In reply to	#578784

kenseto <setoken@att.net> writes:

>On Tuesday, May 17, 2016 at 10:31:56 AM UTC-4, Michael Moroney wrote:

>> >the speed of incoming light as follows:
>> >c'=(c)(Frequency of the rest frame of the source/incoming frequency 
>> >of the source.)

>> But that is incorrect because it makes the implicit incorrect assumption the
>> wavelength remains the same.

>That's not an incorrect assumption. The incoming light becomes a new light 
>source in the observer's frame and the grating defines a new wave length
>for this new light source. The incoming speed must be calculated using the 
>original wavelength of the source.

No, Ken, the diffraction grating acts on the _incoming_ light source's
wavelength.  Saying the wavelength magically changes is just crap you made
up to try to justify a variable speed of light. The grating does not 
magically change the wavelength, it merely diverts light according to its
wavelength.

[toc] | [prev] | [next] | [standalone]

#578791

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-18 10:00 -0500
Message-ID	<7cKdnTblDagVHqHKnZ2dnUU7-e-dnZ2d@giganews.com>
In reply to	#578593

On 5/17/16 9:31 AM, Michael Moroney wrote:
> But that is incorrect because it makes the implicit incorrect assumption the
> wavelength remains the same.

   No, Seto, The Doppler effect shifts both frequency and wavelength
   depending on the relative velocity between observer and light source.

   One wonders how you got so confused.

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578590

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-17 09:19 -0500
Message-ID	<BtqdnYL136TytabKnZ2dnUU7-U8AAAAA@giganews.com>
In reply to	#578502

On 5/16/16 9:53 PM, kenseto wrote:
> On Monday, May 16, 2016 at 7:57:17 PM UTC-4, Sam Wormley wrote:
>> On 5/16/16 2:17 PM, jay moseley wrote:
>>> Speed is not measured. Only assumed.
>>
>>
>>    In astronomy and physics speed is often measure by Doppler shift.
>>    For example Doppler can be used to measure the earth's orbital
>>    velocity, the sun's rotation, the speed of a speeding car, the
>>    recession speed of a distant supernova explosion, and the velocity
>>    of the ejecta from from that supernova.
>
> So why don't they use Doppler shift to measure the speed of incoming light???
>

   Ah Seto, you don't understand that Doppler Effect is used to measure
   the *relative velocity between the source and observer* . The speed
   of light is a finite constant.

   No wonder you are always confused, Seto.

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578786

From	kenseto <setoken@att.net>
Date	2016-05-18 07:08 -0700
Message-ID	<56d66f60-4319-4cfd-8ad7-000e7704a05a@googlegroups.com>
In reply to	#578590

On Tuesday, May 17, 2016 at 10:19:31 AM UTC-4, Sam Wormley wrote:
> On 5/16/16 9:53 PM, kenseto wrote:
> > On Monday, May 16, 2016 at 7:57:17 PM UTC-4, Sam Wormley wrote:
> >> On 5/16/16 2:17 PM, jay moseley wrote:
> >>> Speed is not measured. Only assumed.
> >>
> >>
> >>    In astronomy and physics speed is often measure by Doppler shift.
> >>    For example Doppler can be used to measure the earth's orbital
> >>    velocity, the sun's rotation, the speed of a speeding car, the
> >>    recession speed of a distant supernova explosion, and the velocity
> >>    of the ejecta from from that supernova.
> >
> > So why don't they use Doppler shift to measure the speed of incoming light???
> >
> 
> 
>    Ah Seto, you don't understand that Doppler Effect is used to measure
>    the *relative velocity between the source and observer* . The speed
>    of light is a finite constant.
> 
>    No wonder you are always confused, Seto.

No...wormy you are the one who is confused and uninformed. Doppler shift is due to different relative velocities of incoming light.

[toc] | [prev] | [next] | [standalone]

#578793

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-18 10:07 -0500
Message-ID	<7cKdnTDlDaiDGKHKnZ2dnUU7-e-dnZ2d@giganews.com>
In reply to	#578786

On 5/18/16 9:08 AM, kenseto wrote:
> Doppler shift is due to different relative velocities of incoming light.


   No, Seto, light only has one speed.

   Seto, it would behoove you to learn:

   1. The speed of light in constant, independent of motion of
      the source and observer.
   2. The Doppler effect as it pertains to light.

   Both are found in countless textbooks and online sources.

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578849

From	xxein1@att.net
Date	2016-05-18 13:43 -0700
Message-ID	<d94fe254-73d6-4587-ae40-ac9aa495d779@googlegroups.com>
In reply to	#578793

On Wednesday, May 18, 2016 at 11:07:15 AM UTC-4, Sam Wormley wrote:
> On 5/18/16 9:08 AM, kenseto wrote:
> > Doppler shift is due to different relative velocities of incoming light.
> 
> 
>    No, Seto, light only has one speed.
> 
>    Seto, it would behoove you to learn:
> 
>    1. The speed of light in constant, independent of motion of
>       the source and observer.
>    2. The Doppler effect as it pertains to light.
> 
>    Both are found in countless textbooks and online sources.
> 
> -- 
> 
> sci.physics is an unmoderated newsgroup dedicated
> to the discussion of physics, news from the physics
> community, and physics-related social issues.

xxein:  Sam.  What is the speed of light going outward from r = 2M + 1 meter?

[toc] | [prev] | [next] | [standalone]

#578850

From	Sam Wormley <swormley1@gmail.com>
Date	2016-05-18 16:09 -0500
Message-ID	<M_OdnarWxrdgRKHKnZ2dnUU7-SGdnZ2d@giganews.com>
In reply to	#578849

On 5/18/16 3:43 PM, xxein1@att.net wrote:
> On Wednesday, May 18, 2016 at 11:07:15 AM UTC-4, Sam Wormley wrote:
>> On 5/18/16 9:08 AM, kenseto wrote:
>>> Doppler shift is due to different relative velocities of incoming light.
>>
>>
>>    No, Seto, light only has one speed.
>>
>>    Seto, it would behoove you to learn:
>>
>>    1. The speed of light in constant, independent of motion of
>>       the source and observer.
>>    2. The Doppler effect as it pertains to light.
>>
>>    Both are found in countless textbooks and online sources.
>>
>> --
>>
>> sci.physics is an unmoderated newsgroup dedicated
>> to the discussion of physics, news from the physics
>> community, and physics-related social issues.
>
> xxein:  Sam.  What is the speed of light going outward from r = 2M + 1 meter?
>

   Read my lips.  The speed of light is c.

   Gravitational redshift changes wavelength, momentum and energy, not
   the speed of light.

-- 

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[toc] | [prev] | [next] | [standalone]

#578855

From	"nuny@bid.nes" <Alien8752@gmail.com>
Date	2016-05-18 14:36 -0700
Message-ID	<c756ca04-a85f-4f22-b5e8-0dd603c08673@googlegroups.com>
In reply to	#578786

On Wednesday, May 18, 2016 at 7:08:59 AM UTC-7, kenseto wrote:

>  Doppler shift is due to different relative velocities of incoming light.

  If that were true Doppler radar (and lidar, for those who claim that RF and light are two different things)would not work the way it does.

  All electromagnetic radiation has the same free-space velocity. It's measurable.

  Get over it.


  Mark L. Fergerson

[toc] | [prev] | [next] | [standalone]

Page 12 of 14 — ← Prev page 1 … 10 11 [12] 13 14 Next page →

csiph-web

Does anyone really know the physical cause for time dilation and length contraction?

Contents

#579208

#579265

#578483

#578502

#578559

#578583

#578591

#578788

#578790

#578593

#578784

#578792

#578800

#578791

#578590

#578786

#578793

#578849

#578850

#578855