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Re: From first principles what is the definition of spacetime?

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Arindam Banerjee <banerjeeadda1234@gmail.com> wrote:
> On Sunday, 19 August 2018 19:00:51 UTC+10, Sylvia Else  wrote:
>> On 19/08/2018 5:05 PM, Arindam Banerjee wrote:
>>> On Sunday, 19 August 2018 16:19:27 UTC+10, Sylvia Else  wrote:
>>>> On 19/08/2018 4:08 PM, Arindam Banerjee wrote:
>>>>> From first principles what is the definition of spacetime?
>>>>> 
>>>>> How does it support the transmission of light?
>>>> 
>>>> Physics doesn't answer "how", it only answers "what".
>>> 
>>> Certainly conventional physics answers "how" with theories and supportive facts.
>>> Like gravity as an universal force (theory) is used to explain *how*
>>> things fall to earth (fact).
>> 
>> That's a misunderstanding of what physics says about the situation. It 
>> tells us how to calculate what the trajectory of the falling object will 
>> be. It doesn't tell us why it falls.  To say it falls due to gravity is 
>> circular, since the theory of gravity is just based on the observation 
>> that things fall.
> 
> 
> No, it is not based just on that. The theory of gravity about which you
> are evidently ignorant, but what was taught to me as physics in school
> and followed in my engineering studies, is that every centre of mass
> attracts every other centre of mass in the universe, with a force that is
> proportional to the product of the masses and inversely proportional to
> the square of the distance between them, and the constant of
> proportionality is the gravitational constant G. So mathematically the
> above theory is expressed as f=mMG/RR where the symbols have their obvious meaning.  

Just to give you an idea of the gap, how exactly does a body over HERE
exert a force on another body over THERE? Your paragraph above says “it
just does”. See the problem?

> 
> 
> The "hows" relating to falling, orbital motion, etc. all follow from the
> theory of gravitation.
>> 
>>> 
>>>>> 
>>>>> No mathematical blah, please.
>>>>> 
>>>> 
>>>> That could be difficult - maybe mere words are not up to the task. Is
>>>> science to be so limited?
>>> 
>>> 
>>> Yes. Honesty is there as a must to be followed in conventional physics.
>>> Mathematics in conventional physics is only a brief and convenient
>>> alternative to making a wordy statement.
>> 
>> I strongly doubt that any number of words would suffice to precisely 
>> convey general relativity, or quantum mechanics, or at least not until 
>> the words were merely a codification of the math, and considerably less 
>> comprehensible.
>> 
>>> 
>>> Mathematics can be used by dishonest people to make fallacious points,
>>> for dubious purposes.
>>>> 
>>>> 
>>>>> Just follow the scientific methods.
>>>>> 
>>>>> State your axioms, and build upon them to form a theory.  Then
>>>>> validate that theory with experiment. Make valid predictions with the theory.
>>>>> 
>>>>> 
>>>> 
>>>> Axioms? This isn't mathematics. The starting point for physics is the
>>>> collection of experimental results.
>>> 
>>> Axioms, as basic and undisputable units of information, are required
>>> everywhere, as we all must agree upon them to start any discussion.
>>> 
>>> If your axiom is that I must accept the speed of light to be
>>> independent of the source then with those, like me, who do not accept
>>> this, there is no further discussion.
>> 
>> The constancy of the speed of light is an experimental result. If you do 
>> not accept it, you must believe that the experimenters are lying or 
>> incompetent. Perhaps you should do the experiments yourself, though you 
>> might find them rather demanding to do accurately enough.
>> 
>> Sylvia.
> 
> 



-- 
Odd Bodkin — Maker of fine toys, tools, tables

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From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-18 23:08 -0700
  Re: From first principles what is the definition of spacetime? Sylvia Else <sylvia@not.at.this.address> - 2018-08-19 16:19 +1000
    Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-19 00:05 -0700
      Re: From first principles what is the definition of spacetime? Sylvia Else <sylvia@not.at.this.address> - 2018-08-19 19:00 +1000
        Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-19 02:39 -0700
          Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-19 02:43 -0700
        Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-19 06:21 -0700
          Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 14:01 +0000
            Re: From first principles what is the definition of spacetime? benj <benj.fake@gmail.com> - 2018-08-19 12:45 -0400
              Re: From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-19 09:53 -0700
                Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 20:47 +0000
              Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 18:26 +0000
            Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-19 17:45 -0700
        Re: From first principles what is the definition of spacetime? benj <benj.fake@gmail.com> - 2018-08-19 12:29 -0400
      Re: From first principles what is the definition of spacetime? benj <benj.fake@gmail.com> - 2018-08-19 12:26 -0400
    Re: From first principles what is the definition of spacetime? benj <benj.fake@gmail.com> - 2018-08-19 12:23 -0400
      Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 18:26 +0000
        Re: From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-19 12:05 -0700
          Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 20:47 +0000
            Re: From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-19 14:19 -0700
  From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-19 05:39 -0700
    Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 14:01 +0000
      Re: From first principles what is the definition of spacetime? benj <benj.fake@gmail.com> - 2018-08-19 12:41 -0400
        Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 18:26 +0000
      Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-19 17:32 -0700
        Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-20 14:17 +0000
    Re: From first principles what is the definition of spacetime? Sergio <invalid@invalid.com> - 2018-08-19 13:37 -0500
      Re: From first principles what is the definition of spacetime? benj <benj.fake@gmail.com> - 2018-08-20 14:18 -0400
        Re: From first principles what is the definition of spacetime? Sergio <invalid@invalid.com> - 2018-08-21 13:38 -0500
      Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-21 18:56 -0700
  Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-19 14:01 +0000
    Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-19 17:29 -0700
      Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-20 13:38 +0000
        Re: From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-20 07:01 -0700
          Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-20 14:29 +0000
        Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-20 16:06 -0700
          Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-21 00:43 +0000
            Re: From first principles what is the definition of spacetime? Arindam Banerjee <banerjeeadda1234@gmail.com> - 2018-08-20 18:25 -0700
    Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-20 18:33 -0700
      Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-21 12:52 +0000
        Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-21 11:10 -0700
          Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-21 18:56 +0000
          Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-21 18:59 +0000
            Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-21 19:44 -0700
              Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-22 12:21 +0000
                Re: From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-22 07:10 -0700
                Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-22 14:39 +0000
                Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-22 11:23 -0700
                Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-22 11:42 -0700
                Re: From first principles what is the definition of spacetime? Odd Bodkin <bodkinodd@gmail.com> - 2018-08-22 20:43 +0000
                Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-22 20:17 -0700
          Re: From first principles what is the definition of spacetime? Sergio <invalid@invalid.com> - 2018-08-21 15:06 -0500
            Re: From first principles what is the definition of spacetime? poraty149@gmail.com - 2018-08-21 19:58 -0700
          Re: From first principles what is the definition of spacetime? "reber G=emc^2" <herbertglazier0@gmail.com> - 2018-08-21 19:28 -0700
  From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-19 10:14 -0700
  Re: From first principles what is the definition of spacetime? Alan Folmsbee <omnilobe@gmail.com> - 2018-08-19 12:24 -0700
    Re: From first principles what is the definition of spacetime? john <johnsefton288@gmail.com> - 2018-08-19 13:07 -0700
  Re: From first principles what is the definition of spacetime? mitchrae3323@gmail.com - 2018-08-21 13:02 -0700

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