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Conceptually, imagine a chain of galaxies that leads to your target galaxy. Each galaxy along the chain has some small velocity relative to the galaxy before it. If you add all of those relative velocities together, that should give you the velocity of the target galaxy, right? However, velocities in relativity add in a special way; see the relativistic velocity addition formula. The cosmological recession rate is computed by instead just adding the relative velocities naively, without properly using relativistic velocity addition. That's why we should not be concerned that it can exceed the speed of light.

Also, note that there is not a unique way to define the relative velocity between cosmologically distant objects; See this question for more detail. This is part of why we are fine with talking about recession rates instead of actual relative velocities. There is no unique "actual" relative velocity to even talk about.

Conceptually, imagine a chain of galaxies that leads to your target galaxy. Each galaxy along the chain has some small velocity relative to the galaxy before it. If you add all of those relative velocities together, that should give you the velocity of the target galaxy, right? However, velocities in relativity add in a special way; see the relativistic velocity addition formula. The cosmological recession rate is computed by instead just adding the relative velocities naively, without properly using relativistic velocity addition. That's why we should not be concerned that it can exceed the speed of light.

Also, note that there is not a unique way to define the relative velocity between cosmologically distant objects; see this question for more detail. This is part of why we are fine with talking about recession rates instead of actual relative velocities. There is no unique "actual" relative velocity to even talk about.

In this respect, it should first be noted that there is not even a unique way to define the relative velocity between cosmologically distant objects. See this question for more detail.

That's a consequence of how our Universe's spacetime is globally curved. (Note: spacetime, not space. You might have heard that the Universe is flat; that is unrelated because it's a claim about space.) However, even in a flat spacetime, cosmological recession rates would not correspond to relative velocities. There are already good answers addressing why this is; my favorites are:

• benrg's answer to "Can space expand with unlimited speed?"
• benrg's answer to "Some areas of the universe are moving away from us FTL but surely as we get closer to that area, the speed of expansion would gradually slow?"

Also, if you are comfortable with spacetime diagrams, Part 2 of Ned Wright's cosmology tutorial has helpful illustrations.

Conceptually, imagine a chain of galaxies that leads to your target galaxy. Each galaxy along the chain has some small velocity relative to the galaxy before it. If you add all of those relative velocities together, that should give you the velocity of the target galaxy, right? However, velocities in relativity add in a special way; see the relativistic velocity addition formula. The cosmological recession rate is computed by instead just adding the relative velocities naively, without properly using relativistic velocity addition. That's why we should not be concerned that it can exceed the speed of light.

Conceptually, imagine a chain of galaxies that leads to your target galaxy. Each galaxy along the chain has some small velocity relative to the galaxy before it. If you add all of those relative velocities together, that should give you the velocity of the target galaxy, right? However, velocities in relativity add in a special way; see the relativistic velocity addition formula. The cosmological recession rate is computed by instead just adding the relative velocities naively, without properly using relativistic velocity addition. That's why we should not be concerned that it can exceed the speed of light.

Other good explanations as to why faster-than-light cosmological recession is not concerning include:

• benrg's answer to "Can space expand with unlimited speed?"
• benrg's answer to "Some areas of the universe are moving away from us FTL but surely as we get closer to that area, the speed of expansion would gradually slow?"

Also, note that there is not a unique way to define the relative velocity between cosmologically distant objects; See this question for more detail. This is part of why we are fine with talking about recession rates instead of actual relative velocities. There is no unique "actual" relative velocity to even talk about.

Conceptually, imagine a chain of galaxies that leads to your target galaxy. Each galaxy along the chain has some small velocity relative to the galaxy before it. If you add all of those relative velocities together, that should give you the velocity of the target galaxy, right? However, velocities in relativity add in a special way; see the relativistic velocity addition formula. The cosmological recession rate is computed by instead just adding the relative velocities naively, without properly using relativistic velocity addition. That's why we should not be concerned that it can exceed the speed of light.