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

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  Re: Does anyone really know the physical cause for time dilation and length contraction? Sylvia Else <sylvia@not.at.this.address> - 2016-05-27 11:54 +1000
    Re: Does anyone really know the physical cause for time dilation and length contraction? kenseto <setoken@att.net> - 2016-05-27 07:10 -0700
      Re: Does anyone really know the physical cause for time dilation and length contraction? Sam Wormley <swormley1@gmail.com> - 2016-05-27 09:30 -0500
        Re: Does anyone really know the physical cause for time dilation and length contraction? kenseto <setoken@att.net> - 2016-05-28 10:06 -0700
          Re: Does anyone really know the physical cause for time dilation and length contraction? Sam Wormley <swormley1@gmail.com> - 2016-05-28 13:33 -0500

#580836 — Re: Does anyone really know the physical cause for time dilation and length contraction?

On 21/05/2016 9:19 AM, kenseto wrote:
> On Friday, May 20, 2016 at 10:24:10 AM UTC-4, Sam Wormley wrote:
>> On 5/19/16 7:30 PM, kenseto wrote:
>>> On Thursday, May 19, 2016 at 4:01:20 PM UTC-4, Sam Wormley wrote:
>>>>> On 5/19/16 2:11 PM, jay moseley wrote:
>>>>>>> In other words you have no proof...
>>>>>
>>>>>     In physics, it's called evidence. And there is plenty of evidence.
>>>>>
>>>>>     A muon with such and such momentum and energy can only be created
>>>>>     by a cosmic ray event. We know from other detections of the event its
>>>>>     height above the detector. The fact that the muon was detected at
>>>>>     ground level says that the relativistic gamma had to be greater than
>>>>>     so and so.
>>>>>
>>>>>     There is no doubt that the detected muon traversed the distance
>>>>>     before it could decay.
>>>>>     http://edu-observatory.org/RaySociety/CosmicRays/CosmicMuon.png
>>>>>     http://edu-observatory.org/RaySociety/CosmicRays/Week1.html
>>
>>
>>> There is n doubt that 2.2 us on the muon clock is worth gamma*2.2 us on the earth clock and that's why the muon is able to travel the great distance before decaying.
>>
>>     However, from the perspective of the muon, the distance traveled is
>>     foreshortened by the factor of gamma.
>
> No the distance remains the same. The decay time is lengthened to gamma*2.2 us and that's why it is able to reach the ground before decaying.

You're suggesting that physical processes take longer, as measured in 
seconds. This of course would have to include the physical processes 
used in the measurement of seconds, such that an allowance would have to 
be made accordingly when interpreting the readings on clocks.

Any reasonable observer would conclude that this is an arbitrary 
redefinition of the second, which would appear consistently throughout 
the physics of moving objects (moving relative to some preferred frame), 
and that life would be a lot simpler if the redefinition were removed, 
such that a second as measured by a clock co-moving with the muon 
actually is the second that appears in the physical laws.

The result would be the removal of a need for a preferred frame, and a 
simple way of transforming between frames. That is, special relativity.

Now I'll go back to ignoring you.

Sylvia.


>>
>>     See: Time Dilation of Moving Particles
>>     https://en.m.wikipedia.org/wiki/Time_dilation_of_moving_particles
>>
>>
>>
>>
>> --
>>
>> sci.physics is an unmoderated newsgroup dedicated
>> to the discussion of physics, news from the physics
>> community, and physics-related social issues.

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#580934

On Thursday, May 26, 2016 at 9:54:48 PM UTC-4, Sylvia Else wrote:
> On 21/05/2016 9:19 AM, kenseto wrote:
> > On Friday, May 20, 2016 at 10:24:10 AM UTC-4, Sam Wormley wrote:
> >> On 5/19/16 7:30 PM, kenseto wrote:
> >>> On Thursday, May 19, 2016 at 4:01:20 PM UTC-4, Sam Wormley wrote:
> >>>>> On 5/19/16 2:11 PM, jay moseley wrote:
> >>>>>>> In other words you have no proof...
> >>>>>
> >>>>>     In physics, it's called evidence. And there is plenty of evidence.
> >>>>>
> >>>>>     A muon with such and such momentum and energy can only be created
> >>>>>     by a cosmic ray event. We know from other detections of the event its
> >>>>>     height above the detector. The fact that the muon was detected at
> >>>>>     ground level says that the relativistic gamma had to be greater than
> >>>>>     so and so.
> >>>>>
> >>>>>     There is no doubt that the detected muon traversed the distance
> >>>>>     before it could decay.
> >>>>>     http://edu-observatory.org/RaySociety/CosmicRays/CosmicMuon.png
> >>>>>     http://edu-observatory.org/RaySociety/CosmicRays/Week1.html
> >>
> >>
> >>> There is n doubt that 2.2 us on the muon clock is worth gamma*2.2 us on the earth clock and that's why the muon is able to travel the great distance before decaying.
> >>
> >>     However, from the perspective of the muon, the distance traveled is
> >>     foreshortened by the factor of gamma.
> >
> > No the distance remains the same. The decay time is lengthened to gamma*2.2 us and that's why it is able to reach the ground before decaying.
> 
> You're suggesting that physical processes take longer, as measured in 
> seconds.

No I am saying that a second is not a universal interval of time. It represents a different amount of time in different frames. In the case of the muon second it is worth gamma-seconds according to the earth clock. The reason is the higher state of absolute motion of the muon clock.

> This of course would have to include the physical processes 
> used in the measurement of seconds, such that an allowance would have to 
> be made accordingly when interpreting the readings on clocks.
> 
> Any reasonable observer would conclude that this is an arbitrary 
> redefinition of the second, which would appear consistently throughout 
> the physics of moving objects (moving relative to some preferred frame), 
> and that life would be a lot simpler if the redefinition were removed, 
> such that a second as measured by a clock co-moving with the muon 
> actually is the second that appears in the physical laws.

There is no redefinition--every SR observer claims that his clock second is the standard and the SR math says that a moving second is worth gamma seconds on his clock. 


> 
> The result would be the removal of a need for a preferred frame, and a 
> simple way of transforming between frames. That is, special relativity.
> 
> Now I'll go back to ignoring you.
> 
> Sylvia.
> 
> 
> >>
> >>     See: Time Dilation of Moving Particles
> >>     https://en.m.wikipedia.org/wiki/Time_dilation_of_moving_particles
> >>
> >>
> >>
> >>
> >> --
> >>
> >> sci.physics is an unmoderated newsgroup dedicated
> >> to the discussion of physics, news from the physics
> >> community, and physics-related social issues.

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#580944

On 5/27/16 9:10 AM, kenseto wrote:
> There is no redefinition--every SR observer claims that his clock second is the standard and the SR math says that a moving second is worth gamma seconds on his clock.


   No Seto, that's not what special relativity says. Here' an example
   for you as to who measures what:

   Let A and B be in relative motion with each other. Who is moving and
   who is not moving doesn't matter.

   Let A and B have a relative velocity of v/c
   then  γ = 1/√(1-(v/c)^2)

   Let  ∆t_A' be a proper time interval on A's clock
   Let  ∆t_B' be a proper time interval on B's clock

   From B's perspective:
   B will measure A's clock interval  ∆t_A = γ ∆t_A'

   From A's perspective:
   A will measure B's clock interval  ∆t_B = γ ∆t_B'

      with some numbers (ignoring Doppler effects)

   Let A and B have a relative velocity of v/c = 0.86
   then γ = 1.96

   From B's perspective:
   B will measure A's clock interval  ∆t_A = 1.96 ∆t_A'

   From A's perspective:
   A will measure B's clock interval  ∆t_B = 1.96 ∆t_B'


-- 

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

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#581252

On Friday, May 27, 2016 at 10:30:55 AM UTC-4, Sam Wormley wrote:
> On 5/27/16 9:10 AM, kenseto wrote:
> > There is no redefinition--every SR observer claims that his clock second is the standard and the SR math says that a moving second is worth gamma seconds on his clock.
> 
> 
>    No Seto, that's not what special relativity says. Here' an example
>    for you as to who measures what:

Wormy.....your argument is based on the bogus assumption that Vab is equal to Vba. They are not equal....Why? Because a clock second at A is not equal to a clock second at B. Therefore A and B cannot use the same equal to predict each other's clock rate.

> 
>    Let A and B be in relative motion with each other. Who is moving and
>    who is not moving doesn't matter.
> 
>    Let A and B have a relative velocity of v/c
>    then  γ = 1/√(1-(v/c)^2)
> 
>    Let  ∆t_A' be a proper time interval on A's clock
>    Let  ∆t_B' be a proper time interval on B's clock
> 
>    From B's perspective:
>    B will measure A's clock interval  ∆t_A = γ ∆t_A'
> 
>    From A's perspective:
>    A will measure B's clock interval  ∆t_B = γ ∆t_B'
> 
>       with some numbers (ignoring Doppler effects)
> 
>    Let A and B have a relative velocity of v/c = 0.86
>    then γ = 1.96
> 
>    From B's perspective:
>    B will measure A's clock interval  ∆t_A = 1.96 ∆t_A'
> 
>    From A's perspective:
>    A will measure B's clock interval  ∆t_B = 1.96 ∆t_B'
> 
> 
> -- 
> 
> sci.physics is an unmoderated newsgroup dedicated
> to the discussion of physics, news from the physics
> community, and physics-related social issues.

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#581262

On 5/28/16 12:06 PM, kenseto wrote:
> On Friday, May 27, 2016 at 10:30:55 AM UTC-4, Sam Wormley wrote:
>>
>>    No Seto, that's not what special relativity says. Here' an example
>>    for you as to who measures what:
>
> Wormy.....your argument is based on the bogus assumption that Vab is equal to Vba. They are not equal....Why? Because a clock second at A is not equal to a clock second at B. Therefore A and B cannot use the same equal to predict each other's clock rate.
>

       Try not to be so stooopid, Seto.

>>
>>    Let A and B be in relative motion with each other. Who is moving and
>>    who is not moving doesn't matter.
>>
>>    Let A and B have a relative velocity of v/c
>>    then  γ = 1/√(1-(v/c)^2)
>>
>>    Let  ∆t_A' be a proper time interval on A's clock
>>    Let  ∆t_B' be a proper time interval on B's clock
>>
>>    From B's perspective:
>>    B will measure A's clock interval  ∆t_A = γ ∆t_A'
>>
>>    From A's perspective:
>>    A will measure B's clock interval  ∆t_B = γ ∆t_B'
>>
>>       with some numbers (ignoring Doppler effects)
>>
>>    Let A and B have a relative velocity of v/c = 0.86
>>    then γ = 1.96
>>
>>    From B's perspective:
>>    B will measure A's clock interval  ∆t_A = 1.96 ∆t_A'
>>
>>    From A's perspective:
>>    A will measure B's clock interval  ∆t_B = 1.96 ∆t_B'
>>
>>
>> --
>>
>> sci.physics is an unmoderated newsgroup dedicated
>> to the discussion of physics, news from the physics
>> community, and physics-related social issues.
>


-- 

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

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