Actually there’s very little evidence for either the Steady State hypothesis or the Big Bang hypothesis. Why theoretical physicists and cosmologists have so eagerly embraced one or the other to the exclusion of any other factually unknown possibilities is beyond me. I personally think it’s part of human psychology- even of scientists - of the need to believe in anything rather than to believe in nothing at all.
There does seem to be slightly more evidence in favor of the Big Bang but it’s really not that much more as they both embrace Red Shift measurements of distant galaxies and the determining factor for most scientists today that lead to the rejection of Steady State is the observed existence of so-called CMBR - Cosmic Microwave Background Radiation which calculations re the Big Bang hypothesis does in fact seem to predict……..
Whether or not this observed radiation is in fact the left over decayed radiation from the so-called Universe’s beginning has not been proven to my satisfaction but merely an intuitive assumption.
The logic being because it is both a calculated and observed existence and because we cannot prove a singular direction of it’s origin; it must be coming from every direction; and if it’s coming from every direction it must exist uniformly across the universe and the only way this can occur is if it’s existed since the beginning of the Universe hence it could only have occurred at the instance of the Big Bang.
This train of thought has several flaws the biggest one to me being that human observations regarding anything about the distant Universe is a piss poor guess at best that includes many assumptions hence I refer to it, unlike most theoretical physicists & cosmologists as simply a hypothesis and not a “theory”. Same goes for Steady State; they are both ideas; a hypothesis; having some evidence for each but not much more and not worthy to be called a Theory; little lone an existent preponderance of evidence which Humanity will never be alive long enough to determine.
I could go on & on & on but ummm I won’t. Tired of typing

INTJohn