jby
Any books recommended for dummies? All books that I've found starts with contraviant and covariant tensor, which seems misleading to me.
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Let me guess. You looked at "Shaum College Outline Series" inexpensive good book with lots of worked problems----nothing wrong with book, you were just put off by words "contravariant and covariant". Problem is not with book or with you but with ice-cold nomenclature.Originally posted by jby
Any books recommended for dummies? All books that I've found starts with contraviant and covariant tensor, which seems misleading to me.
Dingus it is then! I've always hated the term "tensor." Great explanation too. I'll be using it later this year if you don't mind. (And even if you did, how would you stop me?)Originally posted by marcus
my private sentiment is that the word "tensor" is misleading
(probably "dingus" would do as well and it is just some
historical accident that they started saying tensor-----but covar
and contravar are descriptive names, therefore could be helpful to understand what they mean.
Can I take a dingus at Y and carry it back to X and compare it with the dingus at X and take the derivative? That'd be like going CONTRARY to the mapping and hence CONTRAvariant, isn't it?Originally posted by marcus
however a trajectory or path in X is COvariant because the map f will transform it into an image path in Y. And taking the derivative of some real-valued function defined on X at a point along that path translates into taking the derivative of a function defined on Y along the image path.
so the solemn ritual of taking a derivative of whatever and in whatever direction goes along WITH the map, getting carried along from X to Y in the same direction as the map goes.
Use caution when using these notes. They were written by a well known crackpot. Most of it is okay I guess (simple stuff copied from texts) but other parts are very wrong.Originally posted by jcsd
While your here, i found these on-line notes on 'Modern Relativity' extermely useful as a refernce work whilst working on the computer:
http://www.geocities.com/zcphysicsms/
What do you find misleading about this? Covariant/contravariant refer to the geometric object in most cases (sometimes it refers to a vector and its dual)Originally posted by jby
Any books recommended for dummies? All books that I've found starts with contraviant and covariant tensor, which seems misleading to me.
I haven't looked over all of them, but they do seem okay to me, I've the feeling he might of lifted them from a textbook.Originally posted by pmb
Use caution when using these notes. They were written by a well known crackpot. Most of it is okay I guess (simple stuff copied from texts) but other parts are very wrong.
The author used to post here for a short time. He came here and imediately started flaming me when he couldn't convince me that a scalar was not defined in modern physics/math as a tensor of rank zero. He was banished when he started to flame the moderator. He was warned to cease flaming but continued and was tossed out.
Pete
Some but not all.Originally posted by jcsd
I haven't looked over all of them, but they do seem okay to me, I've the feeling he might of lifted them from a textbook.
Do me a favor and let's stop that line of discussion here and get back to the original question. Thanks.Originally posted by pmb
It goes on and on and on. He's just a crackpot - plain and simple.