On Sunday, December 17, 2017 at 10:39:18 PM UTC, agrays...@gmail.com wrote:
>
>
>
> On Sunday, December 17, 2017 at 12:21:27 AM UTC, Brent wrote:
>>
>>
>>
>> On 12/16/2017 2:59 PM, agrays...@gmail.com wrote:
>>
>> There's a problem applying SR in this situation because neither the 
>> ground or orbiting clock is an inertial frame.AG
>>
>>
>> An orbiting clock is in an inertial frame.  An inertial frame is just one 
>> in which no forces are acting (and gravity is not a force) so that it moves 
>> with constant momentum along a geodesic.  Although it's convenient for 
>> engineering calculations, from a fundamental veiwpoint there is no separate 
>> special relativity and general relativity and no separate clock 
>> corrections.  General is just special relativity in curved spacetime.  So 
>> clocks measure the 4-space interval along their path - whether that path is 
>> geodesic (i.e. inertial) or accelerated.
>>
>
> *Interesting way to look at it. So free falling in a gravity field is an 
> extension of SR. But the thing I find puzzling is that in GR the curvature 
> of space-time is caused by the presence of mass, yet I can draw the path of 
> an accelerated body as necessarily a curve in a space-time diagram. I am 
> having trouble resolving these different sources of curvature. AG*
>

*Einstein must have figured that since gravity produces an acceleration 
field, and accelerating test particles move along curved paths in 
space-time, he could replace acceleration by inertial paths in a space-time 
curved by the presence of mass-energy. But now, when comparing test 
particles moving along different paths in space-time, he couldn't use the 
Lorentz transformation because the relative velocities of the frames are 
not necessarily constant. So how did he propose to find the correct 
transformation equations, and what are they? And what were the laws of 
physics, in this case gravity, that had to be invariant? AG*

>
>
>> Brent
>>
>

-- 
You received this message because you are subscribed to the Google Groups 
"Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at https://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/d/optout.

Reply via email to