Groups > sci.physics.relativity > #464219

Re: Why did Einstein bring up the concept of simultaneity when he formulate SRT?

From	Thomas Heger <ttt_heg@web.de>
Newsgroups	sci.physics.relativity
Subject	Re: Why did Einstein bring up the concept of simultaneity when he formulate SRT?
Date	2018-07-12 16:09 +0200
Message-ID	<fqp5p6F4b6rU1@mid.individual.net> (permalink)
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Am 11.07.2018 um 23:26 schrieb Volney:

>>>> But if you want to specify to a moving observer how long to boil his 
>>>> egg to get the same result as you then the answer is 5/gamma seconds 
>>>> [sic]. What this mean is that a clock second is not a universal 
>>>> interval of absolute time and therefore you cannot tell the moving 
>>>> observer to boil his eggs for 5 minutes to get the same result.
>>>
>>> No, you tell him to boil for 5 minutes. He will get the same result 
>>> as you:
>>> An egg which is neither soft-boiled nor hard-boiled, but will be 
>>> somewhere
>>> in-between.
>>
>> No Sir!
>> If I told him to boil his eggs for 5 minute on his clock he will get 
>> hard boiled eggs. If I told him to boil his eggs for 5/gamma minute he 
>> will get soft boil eggs as I do.
> 
> No, Ken, you are showing your lack of knowledge of relativistic motion. 
> If the moving observer uses a clock showing his proper time (a local, 
> co-moving clock, for example his wristwatch), he should cook a 5 minute 
> egg for 5 minutes on his clock. Only if he is trying to use the 
> stationary observer's clock should he invoke the gamma factor.


There are no 'stationary observers'.

The point is, that 'stationary' requires a fixed point in respect to 
which the observer is not moving.

But fixed points violate the idea of relativity itself.

IOW: SRT is in contradiction with its own postulates.

Actually SRT requires some kind of Newtonian space in the background, 
which provides the observer with a proper clock and proper measuring rods.

But we could give up 'proper' time and replace it with the time in the 
vicinity of the observer.

This time is not universal, but 'universal' time (or 'proper') is not 
available anyhow.

So we treat time as connected to the local environment and that is, 
where the observer happens to be (wherever that might be).

> It would be a violation of the first postulate (the laws of physics are 
> the same for all inertial observers) for it to be different. Otherwise, 
> the moving observer could determine he is moving by cooking an egg for 5 
> minutes (as shown on a local clock), see it is overcooked, and determine 
> he is moving and how fast. The first PoR forbids this.

So eggs boil similar to the behavior of local clocks, even if these 
clocks tick  s l o o o o w.... . In that case the boiling process takes 
longer, so that time/boiling of eggs seems to be invariant.

>>
>>>
>>> You are very confused about the most basic aspects of special 
>>> relativity.
>>> How to you expect anybody to take IRT seriously? What is all this 
>>> strange,
>>> idiosyncratic vocabulary that you attempt to introduce? What in heck is
>>> this "clock second" that you rant about?
>>
>> You are the one who is confused. Yod.u think that a clock second (or 
>> minute) is a universal interval of time....it is NOT.
> 
> Proper time is the same for everyone.


But how do you find out, whether or not the local time is proper?
...

TH

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