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According to our current understanding of the universe, the concept of an "edge" of the universe is not well-defined. The universe, as far as we know, is homogeneous and isotropic on large scales, meaning it looks roughly the same in all directions. Therefore, there is no known physical boundary or edge beyond which the universe abruptly ends.

When we talk about the expansion of the universe, it is important to note that it is not an expansion into a preexisting space, but rather a stretching of the fabric of space itself. The expansion of the universe is not limited by the speed of light because it is not the movement of objects through space, but rather the expansion of the space between objects.

Now, let's consider the scenario you mentioned. If there was an early star from the beginning of the universe that emitted light and is now extremely far away, the light it emitted in the past has been traveling through space for a very long time. As the universe expands, the space between the star and us also expands. However, if the expansion of space is slower than the speed of light, the light from the early star will still reach us eventually.

It's important to note that as the universe expands, the light from distant objects, including early stars, undergoes a redshift. This means that the wavelengths of the light are stretched, causing the light to become more "red" and lower in energy. In extreme cases, the redshift can become so large that the light is shifted into the microwave or even radio frequency range, making it difficult to detect with optical telescopes.

In summary, while the concept of an "edge" of the universe is not well-defined, if a star from the early universe is extremely far away, its light can still reach us even if the universe is expanding slower than the speed of light. However, the light would be heavily redshifted, making it challenging to detect with optical instruments.

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