Mike_bb's latest activity
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MMike_bb replied to the thread Undergrad Why is gravity a fictitious force?.Ok. If gravity was force then mass of object (gravity mass) in elevator on the surface of the Earth differs from inertia mass of object...
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MMike_bb reacted to Demystifier's post in the thread Undergrad Why is gravity a fictitious force? with
Informative.
The geodesic equation $$\frac{d^2x^{\mu}}{d\tau^2} + \Gamma^{\mu}_{\alpha\beta} \frac{dx^{\alpha}}{d\tau} \frac{dx^{\beta}}{d\tau} = 0$$... -
MMike_bb reacted to A.T.'s post in the thread Undergrad Why is gravity a fictitious force? with
Like.
Do you understand what "fictitious forces" are in the first place? https://en.wikipedia.org/wiki/Fictitious_force They are all... -
MMike_bb reacted to Ibix's post in the thread Undergrad Why is gravity a fictitious force? with Like.
We don't. Newtonian gravity respects the equivalence principle, and that models gravity as a real force. However, if gravity (in...
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MMike_bb posted the thread Undergrad Why is gravity a fictitious force? in Special and General Relativity.I read about equivalence principle. I tried to understand Einstein's thought experiment with elevator and I can't understand why we...
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MMike_bb reacted to Ibix's post in the thread Undergrad Different result with kinetic energy and momentum when a bullet hits a target with Like.
Is the collision elastic or inelastic?
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MMike_bb reacted to Sagittarius A-Star's post in the thread Graduate What Exactly Is The Physical Content Of Maxwell's Equations? with Like.
What also may help for understanding the EM field is to use Geometric Algebra, applied to 4D-spacetime. The wedge product ##\wedge##...
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MMike_bb reacted to anuttarasammyak's post in the thread Undergrad Why is ##(t_1'-t_2')^2## constant in proof(invariance of intervals)? with Like.
As s=s', s is invariant between IFRs, not its time component quantity you refer.
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MMike_bb reacted to Ibix's post in the thread Undergrad Why is ##(t_1'-t_2')^2## constant in proof(invariance of intervals)? with Like.
What do you mean by "constant"? It's the difference in time coordinates of two events, so of course it doesn't change. But I don't think...
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MMike_bb posted the thread Undergrad Why is ##(t_1'-t_2')^2## constant in proof(invariance of intervals)? in Special and General Relativity.Hello! When I was proving that coefficient ##a## ##(s'=as)## is equal to ##1##, I noticed that ##(t_1' - t_2')^2## should be constant...
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MMike_bb reacted to Ibix's post in the thread Undergrad Why can coefficient "a" between spacetime intervals depend on velocity between systems? with Like.
Relative velocity means the velocity one thing measures the other to have. Here, you've calculated the velocity difference between two...
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MMike_bb replied to the thread Undergrad Why can coefficient "a" between spacetime intervals depend on velocity between systems?.At first, I consider two frames: Frame 1: 1m/s Frame 2: 5m/s; (1-5)m/s and (5-1)m/s => absolute value of relative velocity is 4m/s...
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MMike_bb reacted to Sagittarius A-Star's post in the thread Undergrad Why can coefficient "a" between spacetime intervals depend on velocity between systems? with Like.
The absolute value of relative velocities is in both cases not ##4m/s##. If the individual velocities of your 4 frames refer to a...
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MMike_bb replied to the thread Undergrad Why can coefficient "a" between spacetime intervals depend on velocity between systems?.martinbn wrote: I wrote in more details as martinbn said above:
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MMike_bb replied to the thread Undergrad Why can coefficient "a" between spacetime intervals depend on velocity between systems?.##ds_1^2## - interval between two events in frame 1. ##ds_2^2## - interval between the same two events in frame 2. ##ds_3^2## -...