For Mormonism, the theory causes as many theological problems as it does supports them. The biggest of the problems is that some Traditional Christians have used it to support their own ideas of the creation at odds with the LDS view:
Some interpretations of the Big Bang theory go beyond science, and some purport to explain the cause of the Big Bang itself (first cause). These views have been criticized by some naturalist philosophers as being modern creation myths. Some people believe that the Big Bang theory is inconsistent with traditional views of creation such as that in Genesis, for example, while others, like astronomer and old Earth creationist Hugh Ross, believe that the Big Bang theory lends support to the idea of creation ex nihilo ("out of nothing").
A number of Christian and traditional Jewish sources have accepted the Big Bang as a possible description of the origin of the universe, interpreting it to allow for a philosophical first cause. Pope Pius XII was an enthusiastic proponent of the Big Bang even before the theory was scientifically well-established, and consequently the Roman Catholic Church has been a prominent advocate for the idea that creation ex nihilo can be interpreted as consistent with the Big Bang. This view is shared by many religious Jews in all branches of rabbinic Judaism.
Mormonism's creation theology is opposed to both "first cause" and especially "ex nihilo" because there is nothing that has been made that didn't already exist. Matter and energy are eternal, although the materials have changed. Even if the Big Bang resembles more traditional theology, it doesn't completely support either first cause or ex nihilo. The definitions of both are not the same as what the theory explains. First Cause has not been about the creation where the theory postulates a singular event, but about the Creator. Just as problematic is that ex nihilo is "out of nothing" where the theory can only work if there exists something. In fact, a lot of something has to exist that is packed into an extremely heavy glob of energy.
The problem for Mormonism is that the Big Bang doesn't seem to fit the cosmological theology, vague as the descriptions. The theology is broken down into two main parts. First is the nature of any existant substances as eternal and always existant. Joseph Smith as qouted in "Scriptural Teachings of the Prophet Joseph Smith" pg 205, states:
"The elements are eternal. That which had a beggining will surely have an end; take a ring, it is without beggining or end - cut it for a beggining place and at the same time you have an ending place."
He rejected that there was a beggining and end to both matter and, in the next sentence, principals. Nothing that is was never. With the Big Bang, everything had a start with that one singular event. No scientist has given a theory why the glob existed in the first place. That is perhaps where theologins have filled in "the gap" by using it to prove their own teachings.
The second part of Mormon creation theology is the cyclic nature of creation. Whatever was used and discarded would become part of another creation for the use of man and God to His Glory. Nothing goes to waste or simply disappears. The Scriptures explain:
37 And the Lord God spake unto Moses, saying: The heavens, they are many, and they cannot be numbered unto man; but they are numbered unto me, for they are mine.
38 And as one earth shall pass away, and the heavens thereof even so shall another come; and there is no end to my works, neither to my words.
Although the relative nature of time must be considered, the Big Bang does not represent in its present theory a typical cyclical creation. It starts with a point in time when there was an explosion that started the formation of the Universe. That isn't to say that a cyclical creation hasn't been postulated with the theory. Some scientists believe the Universe has expanded and is going to contract back into what it was before the Big Bang. The cyclical "germ" is possible. Joseph Smith seems to have rejected any single event and put the two ideas of the eternal existance and cyclical nature of matter together. The creation was a combination of both:
Now, the word create came from the word baurau which does not mean to create out of nothing; it means to organize; the same as a man would organize materials and build a ship. Hence, we infer that God had materials to organize the world out of chaos - chaotic matter, which is element, and in which dwells all the glory. Element had an existance from the time he had. The pure principles of element are principles which can never be destroyed; they may be organized and re-organized, but not destroyed. They had no beggining, and can have no end.
(STPJS, pg. 395)
There isn't time to explore all Mormon cosmological theology that might be relevant to the discussion. One of those is the infamous star Kolob that has been erronously interpreted to mean the Throne of God, a planet, or the center of the Universe. Each reading seems to indicate a far more symbolic rather than literal place. It is a time-keeper rather than a map location. This is brought up to demostrate how much conjecture comes into interpreting the creation. Definitions are sometimes forced without consideration of other possible meanings or recognition of vagaries.
It is hard to reconcile, although not impossible, what modern revelation has taught about the Universal creation and the Big Bang theory. When a Mormon tries, they end up doing the same thing traditionalist Christians do; redefine definitions to fit the paradigm. It is a theory that has been largely ignored in Mormon creation discussion, but has very distinct implications. Perhaps its relative distance from the creation of the Earth and the Garden of Eden has made it less interesting. Right now it seems immune to a vigorous argument for its rejection or acceptance; while at the same time remains an elephant in the theological room.