Congrats! Illustrates how 3-4 wrongs (unknowns?) make a right.(explained). Event horizon - nice. Even if you "couple it". Gravity: a toughy one. I have an explanation so good that nobody repeats it. An 'unexpected way' is unexpected. JM
On Thu, Feb 13, 2014 at 3:41 PM, LizR <[email protected]> wrote: > Acceleration does cause the formation of an event horizon, I believe, > which might be considered to couple it with gravity (in an unexpected way). > > > On 14 February 2014 09:33, Jesse Mazer <[email protected]> wrote: > >> >> On Thu, Feb 13, 2014 at 2:32 PM, Edgar L. Owen <[email protected]> wrote: >> >>> Jesse, >>> >>> Let me think about this, but it is NOT the observer in "free fall in a >>> gravitational field" that is equivalent to acceleration. It is an observer >>> RESISTING free fall (e.g. standing on the surface of the earth) that is >>> equivalent to acceleration. >>> >> >> Suppose the observer who's not moving on a geodesic path (call her Alice) >> passes through the small spacetime neighborhood where the observer who IS >> moving on a geodesic path (call him Bob) is defining his "local inertial >> frame" (Bob's geodesic path can either by a free-fall path through curved >> spacetime, or inertial motion in flat spacetime, since both qualify as >> geodesics in their respective spacetimes). As Alice passes through this >> region, she performs some experiment and notes the physical result. >> Whatever physical elements are involved in this experiment, Bob can analyze >> them too, and he should predict the SAME result even if his analysis is a >> bit different--for example, if Alice is standing on a platform and lets go >> of a ball, the ball will hit the platform, from Alice's point of view this >> is due to a gravitational force and from Bob's point of view this is due to >> the platform accelerating up towards the ball, but either way the actual >> prediction is the same. So, to say that Bob should observe the same results >> of any local experiment (provided he is approximating everything to first >> order) regardless of whether he's moving inertially in flat spacetime or >> free-falling in gravity is physically equivalent to saying Alice should >> observe the same results of any local experiment (again ignoring >> second-order and higher effects) regardless of whether she's accelerating >> through Bob's region in flat spacetime, or passing through his region >> because he's in free-fall while she is not (say, she's standing on a >> platform resting on a pole embedded in the Earth below, while Bob falls >> past her). >> >> Jesse >> >> -- >> 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 [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/everything-list. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > -- > 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 [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/groups/opt_out. > -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
