Am working to figure out how current deductions about the Universe are made using old data from the Stars. Clearly the Star velocities we measure currently are the past and not their actual current velocities.
For example the Cosmic Microwave Background Radiation shows the Universe's motion over 13 billion years ago.
I also realized that if you are to see it logically the further back in time one sees the higher the drift velocities of galaxies especially the time close to the Birth of the Universe this approximates Hubble's law but it clearly does not mean that's how things are if measured in one given moment in time.
Since we can see the Stars that formed when space was transparent to light about 13 billion years ago then all we see might be all that is since the furthest are still opaque to light.
It could also be good to have a model of the current actual distances, directions and velocities of all bodies in the Observable Universe for example in form of an animation that's constantly updated.
Is my hypothesis correct?
@Max
Its no so much the individual stars that we can see as red shifted, but the galaxies.
There is a clear distance relationship that can be deduced from that red shift.
Andrew,
it's true that the actual current distances can be deduced from red shift. The problem is how does one measure the current velocities of the galaxies.
The expansion of the universe from a single point can not accelerate further than what is observed now. If the universe moves away now from a singular point in space and time, there is no further evidence of new energies received by objects in the universe moving away, to accelerate their movements. The second law of thermodynamics would indicate that lesser energies are retained by moving through space and time. If I throw a ball, it has to slow down somehow. What we see now are images of a distant past, 13 billion years ago, shown by the cosmic microwave background radiation. If point A is the beginning of the expansion and point B is the position of the farthest stars or galaxies in 13 billion years, humans on earth can not observe what is beyond point B or C or D, since the photons of light from point B, C or D has not yet reached us here on earth. If point C is the present position of the stars, we still have no instruments to test such phenomenon as light sources are still travelling from point C to point B ... and we are somewhere between point A and point B. Suppose point D is the edge of the universe and the maximum point of expansion, we are not aware what it is made of. If is elastic or will bust out once matter travelling from A to B to C ... then finally to D. Expansion could accelerate if there is something out there to fuel the movements of galaxies to point D. If there is no new form of energy, then it has to obey the law of entropy, it has to slow down. The whole universe out there for all we know are already between point C and D. Our naked eye aided by instruments can only see up to point B. What if point D , the edge of the universe is fragile and burst out ... then perhaps expansion will accelerate since bursting will be the source of energy. What is point D is elastic, then perhaps, the edge will throw back everything from point D to point A, the universe will experience contaction back to a singular mass. It that will be the case, there will be an acceleration back at a faster rate. It is like throwing a ball with a rubber band attached to it, once it has reached the farthest point it will move back increasing velocity. What is out there beyond point B, C or D. Will the universe eventually burst out or compress back in to a single point, in space and time? Is there an entity beyond point D, the edge of the universe ... if the entire universe is as big as the Pacific or Atlantic ocean ... earth is perhaps the tiniest drop of water at our fingertip once we dip it into the saline sea. A single person in his lifetime trying to understand all of this, is but a tiny molecule of H2O in that tiny drop of water. Amazing.
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