Recent content by nearlynothing

I guess you're talking about gauge freedom? I understand your point, but the discussion in the book assumes one has set up coordinates beforehand, so that measurements can in fact be put into correspondence with the components of the metric at one point. Now of course measuring the metric at one...

The book by Møller is available for free at the link I posted in the OP. The discussion concerns itself with the theoretical possibility of determining the metric by measurements in spacetime, it doesn't propose any method to perform such measurements, nor does it argue that it would be a...

Does anyone know a reference with a discussion on the experimental determination of the metric tensor of spacetime? I only know the one in "The theory of relativity" by Møller, pages 237-240. https://archive.org/details/theoryofrelativi029229mbp

I second for Greenwood's, it is a very good text.

Yes, this is what i was arguing. Considering complete equivalence between gravitational fields and fictitious forces, a gravitational field would come from non-vanishing Christoffel symbols. Going to a local inertial frame you make the Christoffel symbols vanish, and noting that free fall is...

This certainly helps. Thanks :)

I think I see you point, I can't logically infer something because the theory is not complete. Would it be better to phrase it differently? Along the lines of a plausibility argument. Edit: Not complete if all you have is the EP

Good point. I should be more careful before making such a statement. I have to admit I never heard this objection before. Could you give me some reference where I can read more about it? In Straumann's the argument is employed that since you can find such coordinates at an arbitrary point on...

I'm helping write some supplementary notes for an undergraduate GR class at my university. I'm writing about the equivalence principle, do you find this way of stating matters acceptable? The equivalence principle as stated by Einstein asserts that in a sufficiently small vicinity of an event...

As you say, Newton's laws hold at all times and for each particle in the system. What a force does on a particle is to change its linear momentum according to Newton's second law. Now each particle on the spinning gyroscope already has a non-zero velocity in the first place, when gravity acts...

I used this text during my first three semesters at university for my calculus classes. It seems that the author aims at computational proficiency, basically what we did was learn the theory and then solve a whole lot of problems in class atthe same time as the teacher did it on the blackboard...

Is anyone familiar with this book? Differentiable Manifolds: A Theoretical Physics Approach https://www.amazon.com/gp/aw/s//ref=mw_dp_a_s?ie=UTF8&k=Gerardo+F.+Torres+del+Castillo&i=books&tag=pfamazon01-20 https://www.amazon.com/gp/product/0817682708/?tag=pfamazon01-20 If you are, what's your...

All i am saying is that it's never possible to determine which is moving absolutely, no matter if you remember being accelerated or not. I realize i phrased it wrong, i meant the train needs a force to stay in a non-geodesic path.

Lets not call it its own frame then, let's call it the non-inertial frame frame. The train needs a force to stay stationary in this non-inertial frame, and interprets the station as "falling". So the station is moving in this non-inertial frame as opposed to the train which is not, whereas the...

Yeah I agree non-inertial frames can be more tricky. But they are needed in this scenario, I don't think simply saying that the thought experiment goes beyond the range of applicability of SR is enough.