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In this episode of through the wormhole with Morgan Freeman which is titled," when did time begin?", , an Italian physicist makes the following comment about time(not verbatim but it's the point he made):

Time could be a consequence of energy, as opposed to energy being a consequence of and dependent on time. Time could have started as a result of the immense energy that evolved out of the Big Bang.

In an earlier part of the show, an experiment is demonstrated as follows:

In a tank of water, protected from external disturbances, stays still and undisturbed. When a pack of effervescent tablets are dropped into the tank, the water is disturbed and bubbles. This bubbling eventually damps and the static nature of the system is restored, although the colour of the water may have changed a bit. So analogously speaking, space is the tank, still and undisturbed and the Big Bang is the bag of effervescent tablets. As soon as it is dropped( the Big Bang happens), energy is created and the entropy keeps increasing, more and more. This provides a thermodynamic arrow that indicates how energy has evolved and spread with time. As soon as the energy eventually damps out, this cycle may repeat.

My question is why should we consider time to have been initiated at Big Bang, be energy dependent? If it were then there must be a relation such that time is energy dependent. Only as the Big Bang went on to proceed, with entropy increasing, did time pass by.

Time was always present in space and Big Bang was just an event for the beginning of our universe, so that doesn't mean that we must assume second 0 to be the Big Bang just because it was the beginning of our universe right?

Spoilt Milk
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  • Possible duplicate of Did time exist before the creation of matter in the universe? See also the many other similar questions in the "related" column. – sammy gerbil Dec 10 '16 at 21:01
  • @sammygerbil that question is more to do with the existance of time before the BB while mine is to do not with its existence but with its relation with energy and questioning the reason why zeroth second is Big bang – Spoilt Milk Dec 10 '16 at 21:08
  • Seems like the same question to me. In your last paragraph you state your opinion that time always existed, even before the Big Bang. If you are asking "Is time related to energy?" then you need to make that clear in your title. What your quotations are not doing is defining what is meant by time. Everybody has a vague notion and experience of it, but unless it is defined in terms of physics then you cannot decide whether it is related to entropy or energy or whether it was created in the Big Bang. – sammy gerbil Dec 10 '16 at 21:20
  • @sammygerbil sure I'll make that change – Spoilt Milk Dec 10 '16 at 21:42
  • I think you are asking 2 separate questions : 1. Is time a consequence of energy? 2. Did time start with the Big Bang? The 2nd question is clearly a duplicate. The 1st is new but requires some explanation. Your title (and the last 2 paragraphs of your question) is a confusing mix of the 2 questions. What do you mean by the energy-dependence of time? – sammy gerbil Dec 10 '16 at 22:23

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The analogy is misleading because there is no tank. There was neither space nor time "before" the Big Bang, and the universe doesn't expand "into" anything. See also Did spacetime start with the Big bang? and If the universe is expanding, what is it expanding into?

The Big Bang is supposed to be where time and space themselves begin, it's "one end" of the four-dimensional manifold that is the universe described by the FLRW metric, more precisely the singularity where the scale factor $a(t)$ becomes zero. It does not make sense to ask what was "before" the Big Bang in this model because it simply does not include a before.

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ACuriousMind
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  • Thanks for answering! I would also like to know your comments about energy dependent time, do you hunk that the existance of time would probably be due to the consequence of energy? – Spoilt Milk Dec 10 '16 at 21:45