The interpretation I have given is that matter is not being accelerated beyond C, it is simply the distances between galaxies that are increasing faster than C.
With all the talk of the distances between galaxies increasing, it is worth noting that our Milky Way galaxy and its nearest galactic neighbour, the Andromeda galaxy, are actually hurtling towards each other at a speed of 402,000 kilometres per hour.
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The two galaxies are destined to 'collide' in 4 billion years time. I put the word collide in inverted commas because, although the two galaxies each contain hundreds of billions of stars, there is so much empty space between the stars that the two galaxies will simply pass through each other and no actual collisions will take place.
After the two galaxies pass through each other, their mutual gravitational attraction will pull them back together. After oscillating back and forth for a billion or so years they will eventually coalesce into one giant galaxy.
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The two galaxies are destined to 'collide' in 4 billion years time. I put the word collide in inverted commas because, although the two galaxies each contain hundreds of billions of stars, there is so much empty space between the stars that the two galaxies will simply pass through each other and no actual collisions will take place.
After the two galaxies pass through each other, their mutual gravitational attraction will pull them back together. After oscillating back and forth for a billion or so years they will eventually coalesce into one giant galaxy.
I've researched the probability of intergalactic stellar collision.
The distance between neighboring stars in the Milky Way galaxy is approximately equal to 10 million times the diameter of a star.
Stars collide with each other very rarely. By comparison, galaxies collide quite frequently as the distances between galaxies is only approximately equal to 20 time the diameter of a galaxy.
Although stars don't collide when two galaxies merge, the much larger gas clouds do. Shock waves from the collision run through the clouds and actually trigger a burst of star formation.
The distance between neighboring stars in the Milky Way galaxy is approximately equal to 10 million times the diameter of a star.
Stars collide with each other very rarely. By comparison, galaxies collide quite frequently as the distances between galaxies is only approximately equal to 20 time the diameter of a galaxy.
Although stars don't collide when two galaxies merge, the much larger gas clouds do. Shock waves from the collision run through the clouds and actually trigger a burst of star formation.
By the time of the galactic collision, the sun will have become so hot (not yet a Red Giant) that the planet Earth will be scorched dry!
To illustrate this vastness of interstellar space, let's imagine a model in which the diameters of the Sun and Proxima Centauri are represented by table tennis balls. On this scale the distance between the two stars would be 1100 kilometres.
In comparison, imagine a model in which the diameters of the Milky Way galaxy and the Andromeda galaxy are represented by table tennis balls. On this scale the galaxies would only be 1 metre apart.
In comparison, imagine a model in which the diameters of the Milky Way galaxy and the Andromeda galaxy are represented by table tennis balls. On this scale the galaxies would only be 1 metre apart.
Here's a question then, oft used in cosmology classes to confuse, according to a professor I know...
"If space itself is stretching, then why does the device we use to measure space not stretch with it? And if that occurs, we would not be able to measure the stretch - if your ruler grows as the universe grows, it always measures the same... Find any flaws in this argument..."
Space does not extend itself, it is the distance between any two points in the universe that is growing.
The expansion of space does not affect the size of material objects such as galaxies or rulers which are held together by some sort of force.
This is important since we can detect expansion only if our measuring instruments have fixed sizes. If everything were free to expand then our rulers would expand proportionately and we would not notice the difference.
ie, your interpretation of this is that space is an n-dimensional container that is getting bigger, allowing more "space" for galaxies to move into.
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