Re: General Relativity made easy!!

On 8/2/2026 1:55 PM, David Canzi wrote:
> On 7/9/26 16:12, Dawn Flood wrote:
>> This is a fun video:
>>
>> https://youtu.be/foRPKAKZWx8?si=8eaVA3RJ1a-iNU1I
>>
>> Professor Albert Einstein's General Theory of Relativity has been 
>> called the "most beautiful theory in all of Science," and so, it's 
>> well worth everyone's time!!
>>
>> Dawn
> 
> He lost me at about the point where he introduced Christoffel symbols.
> With enough rest and caffeine, I might be able to continue.
> 
> In Back to the Future, Marty McFly disappears in 1985 and reappears
> in 1955, on the same patch of ground he disappeared from.  Why there?
> The writers seem to have assumed that southern California is a
> privileged frame of reference. When I tried to figure out where Marty
> McFly would reappear if there are no privileged frames of reference,
> I ended up concluding that he would die.
> 
> You might be the kind of person who would enjoy figuring this out.
> 

Oh, don't give up!  Here's a short text that will help:

https://math.franklin.uga.edu/sites/default/files/inline-files/ShifrinDiffGeo.pdf

He describes Christoffel symbols on page 57 and then does some calculations.