The seven days of creation have been the subject of an ongoing discussion in the attempt to reconcile Torah and science. The Torah’s account of the seven days of creation seems to clearly contradict the multi-billion year time frame that scientists have developed for Earth's and the universe's creation. However, Rambam and others Jewish scholars would argue that there can be no contradiction between science and Torah. Therefore, the fault does not necessarily lie in science or Torah, but rather in our understanding of the two. Many explanations have been given as to how we could better understand the interplay between science and the world’s creation.
One such popular attempt argues that the “days” of creation mentioned in the Torah are not the 24 hour periods we use to measure days, but are rather large time periods of Earth's early development. According to this opinion, the Torah is actually detailing the progression of God’s development of the universe rather than the time frame for its development.
This argument’s central point uses the following logic: why would God create the universe over a set period of time instead of instantaneously creating it? Because God is extra-temporal, the creation of the universe over time has no meaning. Furthermore, even if God did decide to develop Earth over a period of time, the measurement of time in a pre-universe period would be impossible as time’s measurement requires a frame of reference. On top of that, until the sun was created on the fourth “day,” our modern understanding of time had no meaning. Using this logic, one can argue that if Hashem decided to let the world develop naturally rather than spontaneously, it would be nonsensical to then set the naturally developing world to time constraints such as those set by a 7 day schedule. This, of course, would make sense only if it were even possible to measure that time in the first place.
Other opinions take a more literal interpretation of the Jewish calendar, maintaining both that it has been 5776 years since creation and that the universe was created in both 7 days and billions of years. Assuming for a moment that the Big Bang was the same act of creation discussed in BeReishit 1:1, it is possible to suggest that relativity of time was possible by using the center of the Big Bang as a point of reference. Scientifically, however, the universe is not expanding from a central point of origin, but expanding uniformly. As such, there is no true “center” to the universe. Everything, from every point, is expanding at an equal pace. While there are approaches that effectively deal with this issue, some of which have calculations that roughly coincide with scientific findings, many would argue that they rely primarily on a conglomeration of opinions that were not necessarily meant to be used in mathematical calculations.
It is important to note that the attempt to reconcile Torah and science is not a new phenomenon tied to modern orthodoxy or the 21st century. Rabbeinu Bachya Ben Asher, a pupil of Rashba, who lived in 13th century Spain, cited Kabbalistic ideas to suggest that the universe is several billion years old and full of history of which we have no knowledge. Rav Yitzchak of Acco, a student of Ramban, determined that the universe is 15.3405 billion years old using calculations from Gemara, Tehillim, and other sources. Whether your preferred interpretations of Torah come from Kabbalah or science, or modern or ancient times, it is clear that there are many conflicting arguments that exist, and many more that have yet to be made. But it is also important to note that BeReishit does not just include the creation of the universe. It also includes the story of Adam and Chavah’s sin (3:6) followed by Kayin’s killing of Hevel (4:8). In a Parashah that juxtaposes god’s greatest act of creation with the horrific acts of humanity which followed, perhaps we should bear in mind that regardless of our disagreements over points of Halachah or philosophy, we as a community have two paths before us – either we can repeat the mistake of Kayin and corrupt God's gift of creation through strife and discord, or we could learn from our predecessors' mistakes and utilize God's gifts.