Dark Energy

I have written about this several times in the past. This will be my last comment on the subject of the 'so-called' expanding Universe. As far as we know, there are only four possible states for our Universe: Stable. Expanding. Oscillating. Contracting.
A decade before Hubble, Vesto Slipher found evidence of 'high recession velocities' [red shift of known spectral lines] in nebulae that he observed. Thus dispensing with Einstein's stable Universe.
Edwin Hubble provided evidence that the recessional velocity of a galaxy increases with its distance from the Earth. His distance measurements were made based on a finding that certain 'variable' stars luminosity depended on the rate of variability and thence on their 'brightness' which would decrease due to spherical spreading. He then proposed that the Universe was expanding. This concept was adopted and refined with only a very few observers saying that red-shift also occurs in a Contracting system. The expanding Universe has now run into the problem that the expansion seems to be accelerating! How is that possible? Oh. Let's define a 'Dark Energy' that will provide the needed boost. So.
Please. Someone who knows what they are doing, step up and say, " Enough!".
In a collapsing system; i.e., one in which all objects in a spherical Universe are attracted to one gravitational center and are being attracted to the center by a force that varies inversely with the square of its distance from the center. All objects on any radius will be moving at different velocities depending on their radial location. An observer on any object will detect that all other objects, both closer and further from the center, are 'red-shifted' from themselves. Any objects approaching the center from the opposite side that happened to be observed, would be 'blue-shifted', perhaps even to the point of x and gamma. No. Dark. Energy. Required! Just good, old, unknown, Gravity!