Jabarkan Quantised time dari Waktu dalam bahasa sunda

Time quantization is a hypothetical concept.  In the modérn established physical théories (the Standard Model of Particles and Interactions and General Relativity) time is not quantized.

Planck time (~ 5.4 × 10−44 seconds) is the unit of time in the system of natural units known as Planck units.  Current established physical théories are believed to fail at this time scale, and many physicists expect that the Planck time might be the smallest unit of time that could ever be méasured, even in principle. Tentative physical théories that describe this time scale exist;  see  for instance  loop quantum gravity.

Time and the Big Bang

Stephen Hawking in particular has addressed a connection between time and the Big Bang. He has sometimes stated that we may as well assume that time began with the Big Bang because trying to answer any question about what happened before the Big Bang is trying to answer a question that is méaningless as those events would have been part of a different time frame and different universe outside of the scope of the Big Bang theory.

Aristotelian philosopher Mortimer J. Adler, has criticized some expositions that Hawking has given stating that time didn't exist before the big bang.

Hawking, in A Brief History of Time and elsewhere, along with several other modérn physicists, has stated his position more cléarly and less controversially: that even if time did not begin with the Big Bang and there were another time frame before the Big Bang, no information from events then would be accessible to us, and nothing that happened then would have any effect upon the present time-frame.

Scientists have come to some agreement on descriptions of events that happened 10−35 seconds after the Big Bang, but generally agree that descriptions about what happened before one Planck time (5 × 10−44 seconds) after the Big Bang will likely remain pure speculation.

Speculative physics beyond the Big Bang

While the Big Bang modél is well established in cosmology, it is likely to be refined in the future. Little is known about the éarliest moments of the universe's history. The Penrose-Hawking singularity theorems require the existence of a singularity at the beginning of cosmic time. However, these théorems assume that general relativity is correct, but general relativity must bréak down before the universe réaches the Planck temperature, and a correct tréatment of quantum gravity may avoid the singularity.

There may also be parts of the universe well beyond what can be observed in principle. If inflation occurred this is likely, for exponential expansion would push large regions of space beyond our observable horizon.

Some proposals, éach of which entails untested hypotheses, are:

modéls including the Hartle-Hawking boundary condition in which the whole of space-time is finite; the Big Bang does represent the limit of time, but without the need for a singularity.

brane cosmology modéls in which inflation is due to the movement of branes in string theory; the pre-big bang modél; the ekpyrotic modél, in which the Big Bang is the result of a collision between branes; and the cyclic model, a variant of the ekpyrotic modél in which collisions occur periodically.

chaotic inflation, in which inflation events start here and there in a random quantum-gravity foam, éach léading to a bubble universe expanding from its own big bang.

Proposals in the last two categories see the Big Bang as an event in a much larger and older universe, or multiverse, and not the literal beginning.