What came before the Big Bang?

There was no before the Big Bang—the Big Bang created both time and space as we know it.

At the moment of the Big Bang, everything in the physical universe expanded from a singularity: a point of infinite heat and infinite density. It is important to remember that we cannot imagine the Big Bang as a normal explosion, occurring at a single point in space. Rather, space itself expanded. By the same token, we cannot think of the Big Bang as occurring at a single point in time. Space did not expand in time. Space expanded with time.

This conceptualization of the universe’s birth is made possible by Einstein’s theory of general relativity. According to relativity, space and time are stitched together in a four-dimensional continuum called “spacetime.” Moreover, the fabric of spacetime is not merely a flat stage on which objects and processes in the physical universe interact. Spacetime is warped by the presence of mass, creating gravitational fields. Additionally, the curvature of spacetime governs the motions of particles, including photons, even though they’re massless. As the renowned 20th-century physicist John Wheeler quipped: matter tells spacetime how to curve; spacetime tells matter how to move.

By perceiving spacetime as an active part of the physical universe, we can more easily imagine how both space and time came into existence at the moment of the Big Bang, along with everything else we observe in the universe.

Further Reading: "Nothing: Surprising Insights Everywhere from Zero to Oblivion."

7 thoughts on “What came before the Big Bang?

  1. rippenburn

    Hello Maria
    You say it with such confidence I could almost be forgiven for believing you “There was no before the Big Bang”. What you mean to say is that your equations either do allow for a “before” state or do not work with one. It is unfortunate that we have entered an era when science has replaced religion as the be-all-and-end-all of knowledge.

  2. skapad0868

    Could you say that there was a universe that was before and eventually was recycled into the universe we have today through the Big Bang? There is evidence that supports that there was a time period before the Big Bang making the theory that there was a universe before that eventually decreased in size as ours will eventually too.

  3. shami423shami423

    There are many theories on alternate universes for example universe in a bubble seperated by other bubbled universes like bubbles on liquid surface, universe inside blackhole which constitutes a mother universe or parallel universes.
    But universe in a blackhole seemes most understandable. As we know our universe started with a big bang and there was a lot of heat and pressure. This is because when a star collapsed in our mother universe it created a blackhole. This blackhole consumed first the heat around it which belonged to the collapsed star, then it consumed its dust particles and other atoms and molecules.
    These molecules were squished together into singularity and so were the forces(strong, weak, electromagnetic and gravity). But heat can’t be squished because its just energy.
    As we know that blackhole is like a one way door so all the particles when through this door in a form of string (describing singularity) and heat and other energies also went through it.
    when it came on the other side of the door, it expanded very quickly because there was no force used to maintain its singular form. and so the temperature droped and pressure decreased as the space was expanding. All the forces seperated from each other and atoms began to form. Thats how our universe came into being.

    1. allan christ

      change came before the so called bb and you can not have change unless you have something to change..besides if the bb only spit out the earth and nothing else the earth would be in space not a universe and therefor nothing to expand

  4. Paul-Bohn

    The theory seems to ignore the possibility that, prior to the “big bang”, a previous universe was collapsing into the singularity that became the genesis of the present universe.

    Some puzzling questions:
    How do we define space and time?
    Is it even possible to define them if there are no methods to observe them?
    If there is no measurement capability or change in state, do they exist?
    Does observation itself create or destroy space and time?

  5. allan christ

    so what your saying is that the universial matter is extruded through the black hole in a form of a single []string[] expanding as it came out.. but this would mean that the universe could not have came into being in a instant ..with a bang but more like a buring fuse , and that takes time so space must have already been…

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