Comments by "John Berry" (@user-ud6ui7zt3r) on "This Time Paradox Is Terrifying Scientists! No Solution!" video.

There is a way to avoid the “mirror bounce” method for measuring the speed of Light. It has been shown that, at a certain distance from a black hole, light entering a special zone on one side of a black hole will travel in a curved path (around the backside of a black hole) and will re-emerge on the other side of a black hole.
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From his famous Maxwell Equations, James Maxwell deduced a value for the Speed of Light. It turns out that the equation Maxwell derived is a function of TWO values that both have to be measured, experimentally. In this way, it can be shown that the Speed of Light can "sort of" be measured, by indirect means, because the equation that represents the speed (of light) is exclusively dependent upon values that CAN be measured. (note: one of these values is known as the permittivity of free space, which is equal to 8.85 × 10⁻¹² [farad/m]; the other value is known as the permeability of free space, which is equal to 4π × 10⁻⁷ [henries/m]. Both of these values describe the nature of Magnetism within the region in which they are measured.) But that's not the best part! Do you recall hearing about a phenomenon called Gravitational Lensing? This phenomenon bends the path of light as light passes through a gravitational field that is impressed across a region of Free Space. As a result of observing the phenomenon of Gravitational Lensing, it would seem likely that Gravity directly determines the localized measured value for both permittivity and permeability, across a specified region of Free Space. In other words, just as the strength of Gravity varies in the manner of a smooth gradient across a region of Free Space, it should therefore likely be expected that the localized measured values for both permittivity and permeability also vary (in the manner of a smooth gradient) across the very same region of Free Space. Do you realize what this implies? This implies a direct connection between Gravity and Magnetism! This also implies that Gravity is "hiding" within the four famous Maxwell Equations. It hides within the term that represents permittivity, and it hides within the term that represents permeability. Who knows? Maybe an insight like this could lead to a proper Grand Unified Field theory. Maybe an insight like this could lead to an understanding of Quantum Gravity. Allow me to express these notions in another way. I am suggesting that, in a region where Gravitational Lensing bends the path of light, the path of the photons is curved on account of Gravity smoothly varying (in the manner of a gradient) BOTH the localized value(s) of permittivity AND the localized value(s) of permeability, resulting in photons proceeding SLOWER when they pass by near to a grand source of Gravity and proceeding FASTER when they pass by far away from a grand source of Gravity. The result of the Inner Track being a SLOW path and the Outer Track being a FAST path is that each photon follows a resultant CURVED path.
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@pyotrberia9741 The 'light' doesn't know the path would be curved. Each photon thinks it is traveling straight. Since the light (following the necessary path) emerges, and thus, escapes the black hole, then it stands to reason that some sort of spaceship/space probe could pursue the same path. If the probe succeeded to travel at the speed of light, then the probe would think that its trip around the backside of a black hole was no different than a fast trip down a STRAIGHT drag race track. We can time vehicles that travel down (or along) a straight track.
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@donutwindy Thank you! You're about the only one who saw the BIG PICTURE of what I was trying to get across to everyone. Most people thought that I was merely trying to replace the function of a mirror (in the stated experiment) with capability of a Black Hole to curve the path of light by 180°.
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@3694-k5s Maxwell derived an equation for the speed of light , which is... c = √(1/ε₀µ₀) ; in which c is the speed of light expressed in (ᵐᵉᵗᵉʳˢ/ₛ) . The equation shows that the speed of light is exclusively dependent upon TWO experimentally measured values, namely ε₀ and µ₀. ε₀ is the permittivity of free space... ε₀ = 8.85×10⁻¹² (ᶠᵃʳᵃᵈˢ/ₘ) . µ₀ is the permeability of free space... µ₀ = 4π×10⁻⁷ (ʰᵉⁿʳʸ/ₘ) . SO, if scientists could find a way to alter the observed values for both ε₀ and µ₀ , then it stands to reason that the speed of light could be altered by such means.
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