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Re: Reality versus Math

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kenseto <setoken@att.net> wrote:
> On Friday, May 19, 2017 at 5:17:07 PM UTC-4, Odd Bodkin wrote:
>> On 5/19/17 3:09 PM, kenseto wrote:
>>> On Friday, May 19, 2017 at 1:05:36 PM UTC-4, Odd Bodkin wrote:
>>>> On 5/19/17 9:01 AM, kenseto wrote:
>>>>>> SRians are saying that the PROCEDURE is the same for each observer: Take
>>>>>> a clock that is 1) local to you (and you only), 2) at rest relative to
>>>>>> you, and 3) is standardized. This PROCEDURE is the same for all
>>>>>> observers, and THIS is what they mean by it being universal.
>>>>> So that means that the speed of light is NOT a universal constant but
>>>>> only a local constant.....right?
>>>>> 
>>>> 
>>>> No, it does NOT mean that.
>>>> As pointed out to you before, a speed is a ratio of distance and time.
>>>> 6/3 and 8/4 are the SAME ratios -- they are equal, even though the
>>>> numerators and the denominators are different.
>>>> 
>>>> So if there is a speed and there is a time of 3 to one observer and a
>>>> time of 4 for a different observer, the RATIO is still the same as long
>>>> as the distance is 6 for the first observer and 8 for the different
>>>> observer. And this is precisely what happens. The times between events
>>>> are different, but the RATIO of distance and time are still the same.
>>> 
>>> But material length of a meter stick is a universal constant. 
>> 
>> The length of a meter stick is NOT constant, no it is not. That is your 
>> belief, but it is not true. Experiment has already shown that to be a 
>> false statement.
> 
> The length of a meter stick is certainly constant......that’s why we use
> it to measure distance everyday.

Not so.  The reason why we use one everyday is that, to the precision
needed for everyday uses, the changes in the length of the meter stick are
not enough to matter in those uses. 

It's even true that we don't worry about temperature changes and we use the
same meter siting on days when it is 30 F and when it is 90 F. For steel
this is 0.001 % per degree C. For a 60 F = 35 C temperature change, this is
a change in length of a meter stick of 0.035% or over a third of a
millimeter.  This is trivially easy to measure in the lab, but for everyday
uses we just don't care. 

Same is true for other effects like length contraction -- verified in the
lab but for everyday applications we don't care. Just because we don't care
in everyday uses doesn't mean it doesn't happen.

> 
>> 
>>> In order to get the constant ratio as you asserted physicists had to
>>> invent a new meter stick:
>>> 1 meter=1/299,792,458 light-seconds.
>>> Such ad hoc invention is not doing physics. It is an invention made to save SR.
>> 
>> Ken, this came with SR from its INCEPTION. Time dilation and length 
>> contraction came TOGETHER when SR was introduced. It is not true that 
>> time dilation was developed first and then length contraction was 
>> invented later to save the constancy of the speed of light. The 
>> constancy of the speed of light forces BOTH time dilation AND length 
>> contraction as an immediate logical consequence. Separate those two and 
>> you no longer have special relativity. You have some bastard monster you 
>> dreamed up.
>> 
>> 
>> -- 
>> Odd Bodkin -- maker of fine toys, tools, tables
> 



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

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Re: Reality versus Math kenseto <setoken@att.net> - 2017-05-28 05:51 -0700
  Re: Reality versus Math Odd Bodkin <bodkinodd@gmail.com> - 2017-05-28 17:44 +0000
    Re: Reality versus Math mlwozniak@wp.pl - 2017-05-28 12:18 -0700

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