 |
| This
is an artist's concept of the metric expansion of space, where space (including
hypothetical non-observable portions of the universe) is represented at each
time by the circular sections. Note on the left the dramatic expansion (not to
scale) occurring in the inflationary epoch, and at the center the expansion
acceleration. The scheme is decorated with WMAP images on the left and with the
representation of stars at the appropriate level of development. Credit: NASA |
For more than a century there have been two opposing
theories with regards to the universe. The materialist model which has
dominated and is based largely on the idea that matter and gravity are
the ruling forces of the universe and the electric model of the universe
which states that electricity and magnetism are the ruling forces. Of
course, these are overly simplified definitions and do not do either
theory justice. In the materialist model, it is widely believed that the
universe is 13.8 billion years old, began with a Big Bang(BBT)
and will end in a Big Crunch. The problem with this theory is that it
has more variable data than it has verifiable data, thus suggesting it
is a failed paradigm as well, it allegedly arises from the theory of
General Relativity(GR) which was conceived by Einstein as a "gedankenexperiment"~thought experiment.
This is dangerous in the realm of cosmology as it is impossible to
falsify especially when one uses the theory to interpret data then uses
that data as proof of the theory. This is a perfect example of circular
logic.
The universe may have existed
forever, according to a new model that applies quantum correction terms to
complement Einstein's theory of general relativity. The model may also account
for dark matter and dark energy, resolving multiple problems at once.
The widely accepted age of the universe,
as estimated by general relativity, is 13.8 billion years. In the
beginning, everything in existence is thought to have occupied a single infinitely
dense point, or singularity. Only after this point began to
expand in a "Big Bang" did the universe officially begin.
Although the Big Bang singularity
arises directly and unavoidably from the mathematics of general relativity,
some scientists see it as problematic because the math can explain only what
happened immediately after—not at or before—the singularity.
"The Big Bang singularity is
the most serious problem of general relativity because the laws of physics
appear to break down there," Ahmed Farag Ali at Benha University and the
Zewail City of Science and Technology, both in Egypt, told Phys.org.
Ali and coauthor Saurya Das at the
University of Lethbridge in Alberta, Canada, have shown in a paper published in
Physics Letters B that the Big Bang singularity can be resolved by their
new model
in which the universe has no beginning and no end.
What is old is new again.
Recently physicist Ahmed Farag Ali at Benha University and the Zewail City of #Science
and Technology, both in Egypt, stated in an interview, "The Big Bang
singularity is the most serious problem of general relativity because
the laws of physics appear to break down there," He and his co-author Saurya Das
at the University of Lethbridge in Alberta, Canada, revisited some old
ideas based on the work of theoretical physicist David Bohm who explored
the use of quantum trajectories in place of classical geodesics(the
shortest path between two points on a spherical object). Ali and Das,
reveal in their paper how they took these Bohmian trajectories and
applied them to an equation developed by Amal Kumar Raychaudhuri at
Presidency University in Kolkata, India and using those results they
derived quantum-corrected Friedmann equations which allegedly describes
the expansion and evolution of the universe within the context of
General Relativity.
Old ideas revisited
The physicists emphasize that their quantum
correction terms are not applied ad hoc in an attempt to specifically
eliminate the Big Bang singularity. Their work is based on ideas by the
theoretical physicist David Bohm, who is also known for his contributions to
the philosophy of physics. Starting in the 1950s, Bohm explored replacing
classical geodesics (the shortest path between two points on a curved surface)
with quantum trajectories.
In their paper, Ali and Das applied
these Bohmian trajectories to an equation developed in the 1950s by physicist
Amal Kumar Raychaudhuri at Presidency University in Kolkata, India.
Raychaudhuri was also Das's teacher when he was an undergraduate student of
that institution in the '90s.
Using the quantum-corrected
Raychaudhuri equation, Ali and Das derived quantum-corrected Friedmann
equations, which describe the expansion and evolution of universe (including
the Big Bang) within the context of general relativity. Although it's not a
true theory of quantum gravity, the model
does contain elements from both quantum theory and general relativity. Ali and
Das also expect their results to hold even if and when a full theory of quantum
gravity is formulated.
No singularities nor dark stuff
In addition to not predicting a Big
Bang singularity, the new model does not predict a "big crunch"
singularity, either. In general relativity, one possible fate of the universe
is that it starts to shrink until it collapses in on itself in a big crunch and
becomes an infinitely dense point once again.
Ali and Das explain in their paper
that their model avoids singularities because of a key difference between
classical geodesics and Bohmian trajectories. Classical geodesics eventually
cross each other, and the points at which they converge are singularities. In
contrast, Bohmian trajectories never cross each other, so singularities do not
appear in the equations.
In cosmological terms, the
scientists explain that the quantum corrections can be thought of as a
cosmological constant term (without the need for dark energy) and a radiation
term. These terms keep the universe at a finite size, and therefore give it an
infinite age. The terms also make predictions that agree closely with current
observations of the cosmological constant and density of the universe.
But what does it mean?
While they admit it is not a true model of quantum-gravity, it does
combine elements of quantum theory and General Relativity, which they
say dispenses with the need of the BBT, as well as the existence of dark matter/energy.
Something the proponents of the electric model have dismissed long ago
as being mythological. They also claim that in their model the universe
is filled with what they call "quantum fluid", which they suggest is
composed of hypothetical massless particles called gravitons. In the
electric model this "quantum fluid" is actually plasma and is not
hypothetical and has been proven in a plasma lab by Donald E. Scott and Wallace Thornhill.
Consider also that by utilizing the widely accepted theory of GR, an
acceptance that came through circular logic which to any reasonable
intellect should be considered a fail, they built upon it another theory
which should by all rights be even a bigger failure, yet somehow
reveals a truth that they cannot see due to the blinders of their
pre-existing materialist paradigm. Still, the removal of dark matter and
dark energy, as well as the Big Bang, makes perfect sense to those of
us who favor the electric model for they were created in response to
mathematics built upon a failed paradigm and are contradictory to
empirical data obtained through observation.
New gravity particle
In physical terms, the model
describes the universe as being filled with a quantum fluid. The scientists
propose that this fluid might be composed of gravitons—hypothetical massless
particles that mediate the force of gravity. If they exist, gravitons are
thought to play a key role in a theory of quantum gravity.
In a related paper, Das and another
collaborator, Rajat Bhaduri of McMaster University, Canada, have lent further
credence to this model. They show that gravitons can form a Bose-Einstein
condensate (named after Einstein and another Indian physicist, Satyendranath
Bose) at temperatures that were present in the universe at all epochs.
Motivated by the model's potential
to resolve the Big Bang singularity and account for dark matter
and dark
energy, the physicists plan to analyze their model more rigorously in
the future. Their future work includes redoing their study while taking into
account small inhomogeneous and anisotropic perturbations, but they do not
expect small perturbations to significantly affect the results.
"It is satisfying to note that
such straightforward corrections can potentially resolve so many issues at
once," Das said.
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