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Dimulai oleh The Houw Liong, November 23, 2017, 08:55:20 AM

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The Houw Liong

Show that at least one of the premises is false.

a) Is the argument valid?
A valid argument is one where it is impossible for the premises to be true and the conclusion false. Note that validity does not depend on the truth of the premises, but on the form of the argument. The argument in this paper is valid; it is of the same form as: All whales have backbones; Moby Dick is a whale; therefore Moby Dick has a backbone. So the only hope for the skeptic is to dispute one or both of the premises.

b) Are the premises true?
Also, there are many lines of evidence showing that there is far too little mass for gravity to stop expansion and allow cycling in the first place, i.e., the universe is 'open'.
1) Does the universe have a beginning?

Oscillating universe ideas were popularized by atheists like the late Carl Sagan and Isaac Asimov solely to avoid the notion of a beginning, with its implications of a Creator. But as shown above, the Laws of Thermodynamics undercut that argument. Even an oscillating universe cannot overcome those laws. Each one of the hypothetical cycles would exhaust more and more usable energy. This means every cycle would be larger and longer than the previous one, so looking back in time there would be smaller and smaller cycles. So the multicycle model could have an infinite future, but can only have a finite past.2

Also, there are many lines of evidence showing that there is far too little mass for gravity to stop expansion and allow cycling in the first place, i.e., the universe is 'open'. According to the best estimates (even granting old-earth assumptions), the universe still has only about half the mass needed for re-contraction. This includes the combined total of both luminous matter and non-luminous matter (found in galactic halos), as well as any possible contribution of neutrinos to total mass.3 Some recent evidence for an 'open' universe comes from the number of light-bending 'gravitational lenses' in the sky.4 Also, analysis of Type Ia supernovae shows that the universe's expansion rate is not slowing enough for a closed universe.5,6,7 It seems like there is only 40-80% of the required matter to cause a 'big crunch'. Incidentally, this low mass is also a major problem for the currently fashionable 'inflationary' version of the 'big bang' theory, as this predicts a mass density just on the threshold of collapse—a 'flat' universe.

Finally, no known mechanism would allow a bounce back after a hypothetical 'big crunch'.8 As the late Professor Beatrice Tinsley of Yale explained, even though the mathematics says that the universe oscillates, 'There is no known physical mechanism to reverse a catastrophic big crunch.' Off the paper and into the real world of physics, those models start from the Big Bang, expand, collapse, and that's the end.9

2) Denial of cause and effect

Some physicists assert that quantum mechanics violates this cause/effect principle and can produce something from nothing. For instance, Paul Davies writes:
... spacetime could appear out of nothingness as a result of a quantum transition. ... Particles can appear out of nowhere without specific causation ... Yet the world of quantum mechanics routinely produces something out of nothing.10
But this is a gross misapplication of quantum mechanics. Quantum mechanics never produces something out of nothing. Davies himself admitted on the previous page that his scenario 'should not be taken too seriously.'

Theories that the universe is a quantum fluctuation must presuppose that there was something to fluctuate—their 'quantum vacuum' is a lot of matter-antimatter potential—not 'nothing'. Also, I have plenty of theoretical and practical experience at quantum mechanics (QM) from my doctoral thesis work. For example, Raman spectroscopy is a QM phenomenon, but from the wavenumber and intensity of the spectral bands, we can work out the masses of the atoms and force constants of the bonds causing the bands. To help the atheist position that the universe came into existence without a cause, one would need to find Raman bands appearing without being caused by transitions in vibrational quantum states, or alpha particles appearing without pre-existing nuclei, etc. If QM was as acausal as some people think, then we should not assume that these phenomena have a cause. Then I may as well burn my Ph.D. thesis, and all the spectroscopy journals should quit, as should any nuclear physics research.

Also, if there is no cause, there is no explanation why this particular universe appeared at a particular time, nor why it was a universe and not, say, a banana or cat which appeared. This universe can't have any properties to explain its preferential coming into existence, because it wouldn't have any properties until it actually came into existence.

Is creation by God rational?

A last desperate tactic by skeptics to avoid a theistic conclusion is to assert that creation in time is incoherent.
A last desperate tactic by skeptics to avoid a theistic conclusion is to assert that creation in time is incoherent. Davies correctly points out that since time itself began with the beginning of the universe, it is meaningless to talk about what happened 'before' the universe began. But he claims that causes must precede their effects. So if nothing happened 'before' the universe began, then (according to Davies) it is meaningless to discuss the cause of the universe's beginning.

But the philosopher (and New Testament scholar) William Lane Craig, in a useful critique of Davies,11 pointed out that Davies is deficient in philosophical knowledge. Philosophers have long discussed the notion of simultaneous causation. Immanuel Kant (1724–1804) gave the example of a weight resting on a cushion simultaneously causing a depression in it. Craig says:

"The first moment of time is the moment of God's creative act and of creation's simultaneous coming to be."

Marc Kay's critique of Davies The Mind of God points out further logical and physical fallacies of Davies' reasoning.12 Some skeptics claim that all this analysis is tentative, because that is the nature of science. So this can't be used to prove creation by God. Of course, skeptics can't have it both ways: saying that the Bible is wrong because science has proved it so, but if science appears consistent with the Bible, then well, science is tentative anyway.



Is our universe come from nothing?

The Houw Liong

Universes (multiverses) are created from vacuum fluctuations.
[pranala luar disembunyikan, sila masuk atau daftar.]

One of the great theories of modern cosmology is that the universe began in a Big Bang. This is not just an idea but a scientific theory backed up by numerous lines of evidence.

For a start, there is the cosmic microwave background, which is a kind of echo of the big bang; then there is the ongoing expansion of the cosmos, which when imagined backwards, hints at a Big Bang-type origin; and the abundance of the primordial elements, such as helium-4, helium-3, deuterium and so on, can all be calculated using the theory.

But that still leaves a huge puzzle. What caused the Big Bang itself? For many years, cosmologists have relied on the idea that the universe formed spontaneously, that the Big Bang was the result of quantum fluctuations in which the Universe came into existence from nothing.

That's plausible, given what we know about quantum mechanics. But physicists really need more — a mathematical proof to give the idea flesh.

Today they get their wish thanks to the work of Dongshan He and buddies at the Wuhan Institute of Physics and Mathematics in China. These guys have come up with the first rigorous proof that the Big Bang could indeed have occurred spontaneously because of quantum fluctuations.

The new proof is based on a special set of solutions to a mathematical entity known as the Wheeler-DeWitt equation. In the first half of the 20th century, cosmologists struggled to combine the two pillars of modern physics— quantum mechanics and general relativity—in a way that reasonably described the universe. As far as they could tell, these theories were entirely at odds with each other.

The breakthrough came in the 1960s when the physicists John Wheeler and Bryce DeWitt combined these previously incompatible ideas in a mathematical framework now known as the Wheeler-DeWitt equation. The new work of Dongshan and co explores some new solutions to this equation.

At the heart of their thinking is Heisenberg's uncertainty principle. This allows a small empty space to come into existence probabilistically due to fluctuations in what physicists call the metastable false vacuum.

When this happens, there are two possibilities. If this bubble of space does not expand rapidly, it disappears again almost instantly. But if the bubble can expand to a large enough size, then a universe is created in a way that is irreversible.

The question is: does the Wheeler-DeWitt equation allow this? "We prove that once a small true vacuum bubble is created, it has the chance to expand exponentially," say Dongshan and co.

Their approach is to consider a spherical bubble that is entirely described by its radius. They then derive the equation that describes the rate at which this radius can expand. They then consider three scenarios for the geometry of the bubble — whether closed, open or flat.

In each of these cases, they find a solution in which the bubble can expand exponentially and thereby reach a size in which a universe can form—a Big Bang.

That's a result that cosmologists should be able to build on. It also has an interesting corollary.

One important factor in today's models of the universe is called the cosmological constant. This is a term that describes the energy density of the vacuum of space. It was originally introduced by Einstein in his 1917 general theory of relativity and later abandoned by him after Hubble's discovery that the universe was expanding.

Until the 1990s, most cosmologists assumed that the cosmological constant was zero. But more recently, cosmologists have found evidence that something is causing the expansion of the universe to accelerate, implying that the cosmological constant cannot be zero. So any new theory of the universe must allow for a non-zero value of the cosmological constant.

What plays the role of the cosmological constant in Dongshan and co's new theory? Interestingly, these guys say a quantity known as the quantum potential plays the role of cosmological constant in the new solutions.

This potential comes from an idea called pilot-wave theory developed in the mid-20th century by the physicist David Bohm. This theory reproduces all of the conventional predictions of quantum mechanics but at the price of accepting an additional term known as the quantum potential.

The theory has the effect of making quantum mechanics entirely deterministic since the quantum potential can be used to work out things like the actual position of the particle.

However, mainstream physicists have never taken to Bohm's idea because its predictions are identical to the conventional version of the theory so there is no experimental way of telling them apart. However, it forces physicists to accept a probabilistic explanation for the nature of reality, something they are generally happy to accept.

The fact that the quantum potential is a necessary part of this new mathematical derivation of the origin of the universe is fascinating. Perhaps it's time to give Bohm's ideas another spin round the block.

Ref: [pranala luar disembunyikan, sila masuk atau daftar.] : Spontaneous Creation Of The Universe From Nothing

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The Houw Liong

Matas Vaitkevicius
Matas Vaitkevicius, former Programmer at Saga Plc
Answered Jul 11, 2016

There is this thing called Quantum fluctuations which makes two particles from the vacuum of space, its like it borrows energy to create these particles that then immediately annihilate and since the sum of energy before and after is 0 universe remains happy.

There is this idea that universe is infinite and that time does not have beginning nor end, and there is this thing called entropy that is increasing since there are more ways to be in higher entropy than lower and that eventually universe will distribute itself evenly and it will be cold and dark and it's all even in about one google years.

However Quantum fluctuations would still continue and they would sometimes create more than 2 particles that immediately annihilate but 4 and sometimes 6... and since we are talking about infinite time they would eventually fluctuate more complex things like actual stuff, that can be as complex as you want it's just a matter of time.

Now that probability of complex thing coming into existence based on how much entropy has to go lower and our universe is less likely to be fluctuated into existence than functional human brain with all your memories since brain is smaller and requires entropy to go down less.