The idea of time being a linear/sequential phenomenon is being replaced by simultaneous time. Some Quantum Theory sees spacetime as a complex superposition probability wave function. Superposition means that time is simultaneous. This is similar to an electron cloud in an atom. There is not an electron whirling around the nucleus in this orbital. It exist as a superposition probability wave cloud here too. The electron exist in all probable locations in the cloud orbital with varying degrees of probability simultaneously. When it does need to act as a particle in some atomic event, the cloud collapses and an electron particle is actualized.
In the macro world we live in time is simultaneous. All probable pasts, presents and futures exist and are happening NOW in different temporal locations. We experience time as a linear/sequential function because that is the way our physically focused consciousness works. We weave our way through this sea of probabilities. With each moment we select which probability we are going to actualize and experience as a series of real present physical moment-points. This creates a historical timeline of our life's experiences. However, the probabilities that we do not choose still exist in parallel timelines located sideways in time.
An analogy for time that I like is one of driving a car across the country from east to west. Your current location is the present, to the east is the past, to the west is the future and to the north or south are alternate parallel probabilities. Your road trip creates a historical timeline from your perspective. You have the freedom to choose your path west from the future possibilities and make them a part of your historical experience. However, All locations north, south, east or west exist and are happening whether you experience them or not.
Going back to the beginning, all of time with all of its probabilities came into existence in the same instant. In a way time is infinite similar to how an infinite straight line is the circumference of a circle with an infinite radius. At the same time each point on the circle is valid as the circle's center. Similarly, in an infinite universe every location is valid as the center. The Big Bang thus is not the creation of the universe. It does mark the point where the ultimate black hole at "the end of time" transitions to the ultimate white hole at "the beginning of time". Keep in mind that "time" is no more than the temporal location in a sea of probabilities that all exist and are happening NOW.
Reality is multidimensional and so are we. Consciousness and the spiritual exists outside of time. These are the source that creates and maintains the physical world we experience. Physical reality is not all there is. I have had personal experiences involving my wife and some relatives after they have died. This possibility give time a different perspective also.
