Inertial and Non-Inertial Frames - The Equivalence Principle

Here (GR - 02), we venture into thinking about Inertial Frames of Reference - without the complication of very high velocities near to the speed of light. Then, still at relatively low velocities, we take a first simple look at Non-Inertial (or accelerating) Frames of Reference, in order to consider the way in which results from experiments seem to be modified when such Frames of Reference are used. This leads to a simplistic statement of the Equivalence Principle - its connection with idea of Inertial and Gravitational Mass, and also the idea that ‘gravity can bend light’. Finally, Newton’s basic equations are further manipulated to leave us with an equation for the divergence of a gravitational field ……. an equation which will be most useful later in the final formulation of Einstein’s Field equations (in GR - 19).

This video is part of a series of videos on General Relativity (GR-01 to GR-20), which has been created to help someone who knows a little bit about “Newtonian Gravity” and “Special Relativity” to appreciate both the need for “General Relativity”, and for the way in which the ‘modelling’ of General Relativity helps to satisfy that need – in the physics sense.

The production of these videos has been very much a ‘one man band’ from start to finish (‘blank paper’ to ‘final videos’), and so there are bound to be a number of errors which have slipped through. It has not been possible, for example, to have them “proof-watched” by a second person. In that sense, I would be glad of any comments for corrections ……. though it may be some time before I get around to making any changes.

By ‘corrections and changes’ I clearly do not mean changes of approach. The approach is fixed – though some mistakes in formulae may have been missed in my reviewing of the final videos, or indeed some ‘approximate explanations’ may have been made which were not given sufficient ‘qualification’. Such changes (in formulae, equations and ‘qualifying statements’) could be made at some later date if they were felt to be necessary.

This video (and channel) is NOT monetised

[perdehurcu]

Selamlar. Hocam Muhteşem dersler anlatmışsınız. Çok değerli bilgiler vermişsiniz. Teşekkürler.

[hershyfishman]

8:53 For anyone not familiar with the term gradient as used in this context, it means the slope of the graph: T^2/l

[kennethessenwanger]

Analogy of “Gravitational Flux” creates a paradox since the source was not well defined. Rho was identified as the source then rho on the line of flux was paradoxically equal to 0. Paradox in the context of an energy density Rho that is approaching a constant for flat universe and exponentially expansion, H = constant. Hence, I tend to avoid flux analogy in my theory, and derived equations.

[choh]

36:56 Of course, the people on the spaceship didn't know that the light was traveling diagonally (in the case where the light source was not a laser). Although light must travel diagonally, due to time dilation, the ratio of distance divided by time on the spacecraft is still C.

[choh]

34:37 I think you should take a closer look at this place. If it is a light clock, with the light source on one side of the spaceship is a lamp and when the light is on, the light will radiate throughout space in a spherical shape. Therefore, on the other side of the spaceship, if there is a sensor, it will definitely receive a signal and tick. In this case, the person in the red frame will see the light travel with the speed C. The person on the spaceship will see the light traveling from the side of the ship to the other at the speed C.(Delta t')/(Delta t') = C (Because of time dilation by velocity). Thus, both frames of reference see light traveling with speed C.
But in the case of the ship replacing the light source with a laser, the result will be different because the laser beam has a direction, not a spherical propagation. If the blue spaceship is moving with velocity v, the laser beam will deflect downwards on the other side of the ship. Therefore, with this deflection angle, it is clear that the people on the spaceship will know how fast they are going.
I have such an opinion.

[choh]

38:40 In my opinion (geometrically provable of course), if the light source were a laser, when the spaceship traveled at a constant velocity, the path of the laser would be linear (which is diagonal, deviating downwards on the right side). across). In the case of an accelerating spaceship, the path of the laser beam will be a curve.

[lowersaxon]

My answer to floating in outer space and free falling in a grav. field being the same is: wait a second!