Is entropy absolute (as in absolute temperature)? Following this question on the Entropy at the Big Bang where I asked:

Since Entropy always increases (in general); its expected that the entropy at the beginning of the universe should be the lowest possible.

One answer to this by Chris White suggested that:

This is a logical fallacy. From the premiss "entropy always increases," we can derive the conclusion "the entropy at the beginning of the universe was lower than it is now." We cannot from this one premiss say anything about the absolute entropy back then. In particular, there is no reason it need be close to zero or a minimal value in any sense. Is simply cannot be maximal.

But this seems to be, to some extent invalidated by another answer where its stated that

The quark-gluon plasma has been shown to be a [minimal entropy fluid] .

This plasma existed a few milli-seconds after the Big-Bang; it seems rather incredible that entropy can be at a minimum slightly after the Big Bang, but not at it (if or when this can be given a meaning).
This leads to a question: If the Quark-Gluon plasma is as far theoretically we can go far back, and its entropy is at a minimum; then can we not set it as zero - thus making entropy  absolute, in the same way that temperture is absolute.
 A: In classical thermodynamics, only changes in entropy ever matter ($dS = \dfrac{dQ}{T}$ for reversible processes), so it is not meaningful (though it may be convenient) to define an absolute entropy.
HOWEVER, in statistical mechanics, entropy has a probabilistic interpretation:  $S = -k_B\sum_i p_i ln p_i$, where $k_B$ is Boltzmann's constant and $p_i$ is the probability that a system in a given macrostate will be in the $i$th corresponding microstate.  If the probabilities are determined, then this constitutes an absolute measure of entropy.
HOWEVER, applying this absolute measure to the entire universe is problematic, because applying probabilities to the universe as a whole, with no evident parent distribution to be sampling from, is not well defined.
A: Yes, thermodynamic entropy is absolute. No need to invoke early universe, just the Third Law of Thermodynamics. If the system has only one possible configuration (i.e. a perfect crystal at zero temperature), the entropy is zero. Not the lowest: zero.
Another way to look at this: if you try and rescale, the entropy would cease to be extensive. Suppose you have $S_A + S_B = S_{A+B}$, where $A$ and $B$ are two independent systems and $A+B$ the composite. If you rescale by a constant $c$ all quantities, you have $S'_A + S'_B =(S_A + c) + (S_B + c) = S_{A+B} + 2c = S'_{A+B} + c$. So $c$ has to be zero to make the new entropy extensive again.
Personally, I like to think of zero entropy as the entropy of an empty system. You can't go lower than that. Hope it helps!
A: Strictly from a logical point of view, If the universe's entropy,is always increasing, it follows, that the universe's entropy must have been at a minimum (but not zero), "shortly after" the Big Bang.  
Just like we don't know if there is something "colder" than -273 degrees Celsius, because we can not measure it, we can not find the entropy of the universe at the BB.  However, I agree that just like we defined absolute zero temperature as -273 (0 Kelvin), we could define the universe's entropy, "shortly after" the BB, as a minimum (but not zero).  Hopefully, this would serve a useful purpose. 
