Metric light distance and gravitation

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Discussion Overview

The discussion revolves around the relationship between the speed of light, the definition of the meter, and the implications of gravitational effects on these concepts. Participants explore theoretical aspects of light propagation in curved spacetime, the nature of time, and the implications of massless photons in gravitational fields.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions the implications of defining the meter based on the speed of light, suggesting that gravitational fields may alter measurements of distance and time.
  • Another participant proposes that the photon, while massless, could still have a rest mass in a certain frame of reference, challenging the conventional understanding of its properties.
  • A later reply reflects on Einstein's equation M=E/c^2 and suggests that the constant speed of light serves as a universal frame of reference, which could have implications for the nature of time.
  • One participant expresses uncertainty about the concept of time, suggesting that it may be arbitrary and questioning whether it can be removed from the equations of motion without losing meaning.
  • Another participant reflects on the cyclical nature of defining time in relation to velocity, proposing that time travel discussions may be based on misunderstandings of spacetime dynamics.

Areas of Agreement / Disagreement

Participants express a range of views on the nature of light, time, and gravitational effects, with no consensus reached. Several competing ideas are presented, particularly regarding the implications of massless photons and the definition of time.

Contextual Notes

Participants acknowledge the complexity of the concepts discussed, including the potential for circular reasoning in defining time and the challenges of reconciling different frames of reference in the context of relativity.

Who May Find This Useful

This discussion may be of interest to those exploring theoretical physics, particularly in the realms of relativity, quantum mechanics, and the philosophical implications of time and space.

madhatter106
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I searched because I didn't want to add yet another light speed question.

Here's what I've been wondering about. the meter is defined now by meters per second of the speed of light so that a meter is 1/299,729,458 of a sec.

since these measurements are based upon a tangent space then the topology is curved near a gravitational body. once the light moves out into open space if it's flat then contraction occurs in the measurement. as the distance increases and the light encounters another gravitational body then it's a curved manifold and to maintain the constant it would increase. this introduces 2nd order curvature yes?

then when light encounters this gravitational potential the use of the schwarzschild metric determines the curvature of the space time. is not the meter already conformed to a gravitational potential? so is it that with any gravitational fields in similarity to the defined value would be regarded as unchanged? How do you then calculate the potential between flat and curved?

I look at it in that in order to set the frame it requires a rotation. so we have a distant solar system, the light we receive based upon the motion and intervals and the frequency by it's color.

Ok here's the paradox to me:
But isn't this all assumed on the rest mass of photon to be 0 with a 1 spin? if it has zero mass then the frequency would be zero and the wavelength would be everywhere and nowhere. ? the setting to a photon of zero mass negates any frequency change induced by gravity, but wouldn't the gravitational effect on the frequency also change the photon energy and that has BIG implications. but the current theories use the zero mass photon with angular momentum. when that photon is stripped of it's energy trying to move past the event horizon you're left with no photon and 1 spin, how? conservation of momentum is violated if you get rid of the spin right?

Ughh this makes my head spin.

back to the meter distance as a function of the speed of light, it's seems like a cheat to remove external frame distance measurement in order to avoid contradictions.
 
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I'll respond to myself here with some light night musing...

absolute speed of light being set equal to 1.

the only thing known to be at 1 is the photon. establishing a frame of reference is meaningless as it becomes infinity or zero, both have no value but one can have value. Now since the photon sets the limit at 1 and is in our frame of reference it then has value and can be assumed to have a rest mass.
 
So last night with some more meditation, and let me clarify here my use of meditation. I'm not talking the philosophical transcendental nature of enlightened consciousness induced by foreign chemical action. No, it's simply a deep thought process of thinking thru many permutations and to help clarify a thought or gain insight of understanding by pulling together all the inputted data I've collected.

As I was working thru the concepts I've posted here I had a AHAH! moment that crystallized the picture, unfortunately there is a missing piece that is nagging at me and hopefully I can figure it out. And I also wonder if this was what perturbed einstein, and I'll get to what and why I think that.

Ok here we go.
Einsteins M=E/c^2 and the limit of c=1
Up until last night I thought I understood it since I could work thru various what if's but still looked at it as though there's got to be a paradox here. many posts here deal with these things. with the original post here I made is based upon a false assumption. From my new understanding the reason for c=1 is to create a universal constant frame of reference that is not going to be altered by another frame. it's beautiful really, the velocity of light can be any number and that is the point, since it has the fastest known velocity it's sets the limit.

I went back to time being defined by a unit of measure between two events. without a universal constant to space time the background for all reference frames time would become arbitrary and messy and no one could observe or measure any other reference frame. hence the c=1. but what about time?

I've always struggled with the arbitrary unit of time we live by, I have zero concept of it in a way that is different from most everybody. the passage of time for me is strange, my internal clock is not sync'd to solar events. I have DSPS ( delayed sleep phase disorder) so my sleep wake cycle pattern has me on a 28~30 hr day since childhood. So here's the tie in, I've always found time to be arbitrary because I can't sync with it and don't fit into everyone elses' reference. I remember when I was very young realizing that depending upon your rate of cycle around the sun it would alter my time definition from someone on a different cycle period.

Then it occurred to me, there is no universal time constant. Starting with a location of event A at xyz and moving to event B at x1y1z1 with x=1 and y,z=0 traveling in this instance in just the x direction. setting the velocity between A~B at a fraction of c, would define the two events with time being a unit of T= x1,y1,z1-x,y,z/v/c. In using the constant of c to define time removes an arbitrary measurement. defining time by the velocity would create a cyclical definition however that is already the case. In the way I look at it, time being a function of the velocity is only to define the two events and does not carry an actual number just a ratio. So the closer the velocity gets to c, the events get closer together in space time. time is defined by the distance ratio to c. not the orbit of a planet or the decay interval of atoms.

This had to be the picture in Einsteins (yes this is my assumption) head. this definition also shows that time travel is not a velocity function. Trying to define time travel by velocity is a misunderstanding of the nature of space time. with the events being defined by the distance velocity ratio to c, increasing the velocity to c only gets you to a point of non-movement in space time. and conversely a zero velocity has no second event to define. chasing time travel with the hypothetical attainment of V=c only nets zero movement in space time and thus no event.

The nagging is now, are we attributing a unit 'time' to events that is not needed. I ask this, and please really think about it, due to that V has a time function in already and this creates a circular logic. extracting the time from the velocity that has time as it's function isn't defining time but defining the time of that velocity in it's own reference frame. whereas the velocity of c is not constrained to a reference frame.

this may be an already understood thing, asking about time travel in reference to velocity is a non logical question. Space time as I can now see it 'time' is a fabrication in attempting to understand the defined two events with a velocity vector between them. I don't know if time can be removed from the equation as we know it without creating a cyclical 1=1 with no value. I'm going to try and work out some equations and see what I get. might be a fools errand, but its nagging me that there is something there.

Or have I lost my marbles?
 
I may have it soon, there is no absolute time.
 

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