Can the gravity of one entire galaxy slow down an astrophysical jet emitted from its central black hole?

Question

Let say we are talking about our Milky way and Sagittarius A* emitted a astrophysical jet. If the galaxy was 150 000 ly wide would its gravity with dark matter included eventually slow down that jet keeping in mind that gravity of a disk loses strength slower than a sphere as a black hole is?

rfl · Answer

No.
These jets are jets because they are faster than the escape speed of the various relevant objects (central black hole / Active Galactic Nucleus / host galaxy). Thus, gravity is not relevant in slowing it down. For order of magnitude, the escape speed of the Milky Way galaxy is about 650km/s, but these jets are relativistic, i.e. one or two orders of magnitude faster.
Instead, jets are slowed down by Ram pressure as they encounter the intergalactic gas. This is why they "puff up" (rather than fall back on a parabolic orbit). Classic example is the jet from M87:

Can the gravity of one entire galaxy slow down an astrophysical jet emitted from its central black hole?

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