### Key assumptions for this hypothetical
- The medium is static: c(r) increases with gravitational field strength |g(r)|, and does not depend on frequency (nondispersive).
- Treat space like a graded-index optical medium with refractive index n(r) ∝ 1/c(r). Stronger gravity ⇒ larger c ⇒ smaller n.

### What happens to the laser pulse

- Speed:
  - **Increases continuously** as the pulse moves into stronger gravity. The front of the pulse reaches higher-c regions before the rear, so the pulse **stretches in space** (its spatial extent grows).

- Frequency and wavelength:
  - In a static graded-index medium, the **frequency stays constant** along the ray for stationary observers tied to the medium.
  - The **wavelength grows** with c: λ(r) = c(r)/f. Approaching the black hole (larger c), the beam’s **wavelength increases**; the light does not change color for those observers, but its spatial period lengthens.
  - Energy flux spreads: with the pulse lengthening and the beam defocusing (see below), **intensity drops** even though photon energy (hf) is unchanged.

- Trajectory (bending/lensing):
  - Rays curve toward regions of higher refractive index (lower speed). Here n decreases inward, so the gradient points outward. The pulse therefore **bends away from the black hole** as it approaches—an effective **diverging (negative) gravitational lens**.
  - Consequences:
    - For an exactly radial shot, there’s no lateral index gradient, so the pulse **goes straight in** while accelerating.
    - For any nonzero impact parameter, the path **curves outward**, producing a deflection with the **opposite sign** to general-relativistic lensing.
    - Near the mass, paths are more strongly deflected outward because the index gradient is steeper.
  - Travel-time effect: because c is larger near the mass, a path that dips closer to the black hole yields an **earlier arrival** than in empty space with uniform c—a kind of **inverse Shapiro effect** (a time advance instead of a delay).

### Net picture
- As the pulse nears the black hole: its **speed rises**, its **frequency stays the same** (for stationary observers) while its **wavelength increases**, and its **trajectory defocuses away** from the mass unless aimed exactly radially inward.