cianfa72's latest activity
-
cianfa72 reacted to Ibix's post in the thread Undergrad Understanding Relativity of Simultaneity in Resnick, Part I with
Like.
Not really, because you don't have a sense of "location" without defining "at rest", and you are again using "in a reference frame"... -
cianfa72 reacted to Ibix's post in the thread High School Prove the velocity of a moving object is absolute in one IRF? with
Agree.
Nothing can leave the future light cone of any event on its past worldline, would be the formal statement that generalises to curved... -
cianfa72 replied to the thread Undergrad Linear vs rotary motion.Note that this centripetal force (inward proper acceleration) is given by the spring acting on the mass (not the other way around). The...
-
To explain this further, let’s consider a simple mass-spring accelerometer attached radially on a spinning wheel. The mass is deflected...
-
It isn't experiencing "centrifugal force". It's experiencing internal forces between its parts because they push on each other. Those...
-
No. The local centrifugal force does not have a cause. It is not a physical thing subject to cause and effect. It is purely math. It can...
-
cianfa72 replied to the thread Undergrad Linear vs rotary motion.In the context of GR, the following invariant physical definition of unaccelerated is taken: a body is unaccelerated (zero proper...
-
cianfa72 reacted to Ibix's post in the thread High School Car spinning on a frictionless sheet of ice = absolute motion? with Like.
Depends on what you mean by "absolute motion". You can detect rotation (and acceleration in general) with a "closed box" experiment. A...
-
cianfa72 replied to the thread Graduate Trivial fiber bundle vs product space.Sorry, I'm not that skilled in this area. What I can say is to take a look at Lee - ISM chapter 10 Ex. 10.37. As far as I can tell, in...
-
cianfa72 replied to the thread Graduate Trivial fiber bundle vs product space.By definition ##\mathbb R^2## as set is ##\mathbb R^1 \times \mathbb R^1##. Furthermore as topological space it carries the product...
-
cianfa72 replied to the thread Graduate Trivial fiber bundle vs product space.Sorry, I can't understand. If I give you explicitly ##A \times B##, I'm giving you a product that can be treated as a (product) fiber...
-
cianfa72 replied to the thread Graduate Trivial fiber bundle vs product space.Maybe I can't explain my point. If I give you explicitly ##A \times B## this naturally includes the projections on the factors. It is...
-
cianfa72 replied to the thread Graduate Trivial fiber bundle vs product space.So I believe what I call trivial fiber bundle is what for instance Lee - Introduction to smooth manifolds calls product fiber bundle ##A...
-
Sure. Locally the two circles are one dimensional. When they approach closely enough they look like lines. Suppose one line W is [w...
-
cianfa72 replied to the thread Graduate Trivial fiber bundle vs product space.Yes. Nevertheless do you agree that a product has got two canonical/natural projections ? A globally trivializable fiber bundle has only...