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1. Expansion Of Spacetime

   Linked via "Background Temporal Gradient"

   The Cosmological Event Horizon ($d_E$) defines the boundary beyond which events occurring now can never causally influence us, even in principle, due to the exponential nature of the acceleration. If the Dark Energy equation of state parameter, $w$, remains constant ($w=-1$, or $\Lambda$CDM), the event horizon is fixed at:
   $$dE(t) = a(t) \int{t}^{t_0} \frac{dt'}{a(t')}$$
   Objects crossing this horizon recede faster than the [speed of light](/entries/speed-of-li…