Can
space exist without time? Is a condition of no-space realizable? Big bang is
supposed to be the beginning of time. What was there before big bang? Was space
present before big bang?
Space can exist without time. Time dimension is not required to explain space.
Spatial dimensions can be explained without time i.e. to say, for explaining
spatial dimensions time is not required. We can imagine space (spatial
dimensions) without time. But the reverse – to imagine time without space is
not possible. A condition of no-space (without spatial dimensions) is not
realizable. Space and spatial dimensions are independent of time. We assume big
bang to be the beginning of both space and time. In fact to be more precise,
big bang was the beginning of time, not space. As a condition of no-space is
not realizable, we can assume space to be present even before big bang or in
other words space was present before the beginning of time. All the uncertainties
that arise when we talk about a pre-big bang universe are caused because of the
concept of no-space (without spatial dimensions). Most of the modern scientists
think that big bang is the beginning of both space and time and there was no
space and time in existence before that. To explain big bang and the events
leading to that event, we must have a clear idea about what existed before big
bang.
The pre-big bang universe was devoid of matter but not energy. Energy was
present even before big bang which is the most important concept on which the
modern day scientists disagree. They argue that nothing was present before big
bang – no matter, no energy, no space and no time. If that is true, that would
be the violation of the Law of conservation of energy i.e. energy can be
neither created nor destroyed, it can only be changed from one form to another.
If big bang is the beginning of everything then how can we account for the
enormous amount of energy that appears at the instant of the bang? It must be
assumed to be created out of nothing which would be the violation of the law of
conservation of energy. So to satisfy the law of conservation of energy, we
must assume that energy was present even before big bang. This energy that
existed prior to big bang was the total energy of the observable and
non-observable universes together that we have today.
How did this energy exist prior to big bang? In what
form?
We have already seen that space was present even before big bang. But this
space was devoid of matter and so this condition of space is called vacuum.
This vacuum spread into the infinite vastness of space and contained energy
within it in the form of vacuum fields. These vacuum fields contained the total
energy of the universe and thus the law of conservation of energy is
satisfied.
THE PRE-BIG
BANG VACUUM
The newest concept is that of the pre-big bang vacuum. The pre-big bang vacuum
is different from the space of post-big bang universe. It was devoid of matter
and so equivalent to vacuum. Since we assumed that space was present even
before the big bang, we have to approximate that condition to vacuum which is
defined as a state of space devoid of matter. The pre-big bang space existed in
the absence of time and so is different from the post-big bang space. Pre-big
bang space contained energy within it in the form of vacuum fields. Post-big
bang space contained matter within it and it consisted of the time dimension
within it to make it the space-time continuum. Post big bang space expanded
from the initial singularity and the expansion is still continuing at an
accelerated pace.
How can we
differentiate post-big bang space from pre-big bang space?
Pre-big bang space is
that which is devoid of matter and which contained energy in the form of vacuum
fields. Time dimension was absent in the case of pre-big bang space. But time
dimension is present in the case of post-big bang space and together it forms
space-time continuum. Post-big bang space is that space which is filled with
matter or which is created as a result of materialization of energy to matter.
This space continue to expand into the pre-big bang space that existed prior to
big bang or in other words, the post-big bang space occupied the place of
pre-big bang space when it expanded as a result of the big bang. Today also it
continues to expand into the pre-big bang space that existed prior to the bang.
IMPORTANT NOTE - In our
universe after big bang, space and time should not be treated as separate entities but only
together as spacetime continuum as established by Albert Einstein in his theory
of relativity. The concept of space being independent of time is mainly applicable
to the scenario which existed before the big bang. In that situation, there was
no time but there was space: 2 types of space - space with energy and space without energy....
1 comment:
Superb!!!
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