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-4

I am a theoretical philosopher; I rely on Causality as my LCD regarding more-perfect Public Policy. The Causality Principle of Special Relativity is the main reason mass cannot travel faster than lightspeed. I am not here to discuss special circumstances or supernatural events. Public Policy must be written respecting natural law. The inability to travel ...

1

The null curves have: $$0 = ds^2 = -dt^2 + e^t dx^2$$ that gives you the null curves differential equation: $$\frac{dx}{dt} = e^{-t/2}$$ Solving it you get the equation of the null curves, and so the light cone.

1

In fact, you have $\{\psi^a(x), \bar \psi_b(y)\} = 0$, as an operator, for a space-like interval $(x-y)^2 <0$ (stricly speaking, this is a distribution, for instance, at $x_0=y_0$, this is the distribution $\delta^a_b \delta^3(\vec x-\vec y))$, together with relations $\{\psi^a(x), \psi_b(y)\} =\{\bar \psi^a(x), \bar \psi_b(y)\} = 0$ Now, if you look ...

5

Whenever an amount of mass (or mass equivalent in energy) finds itself inside a volume smaller than the event-horizon for a Schwarzschild black hole of that mass ($R = \frac{Gm}{c^2}$), then you have the necessary and sufficient condition for a black hole. In fact, the black hole may form before the matter reaches this point, provided that it will reach it ...

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