Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: puppypower on 24/01/2017 16:22:34
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A quantum universe implies that there are only a finite number of distinct states and that not all states are possible. For example, there are five energy levels for the hydrogen atom, each of which requires a very specific photon energy. There is nothing random about this.
The random universe assumption assumes everything has a finite probability, which is not the case in a quantum universe. A quantum universe has 1.0 or 0.0 odds; on or off.
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Not sure about your meaning PP? Are you mixing statistics leading to probability with the way we find defined quantum states to exist? The first is just about the probability of one of those defined states to fall out.
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There are no quantised states for the kinetic energy of a free particle. A photon can have any energy.
There are only 6 sides to a cube, but dice games are entirely probabilistic.
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A quantum universe implies that there are only a finite number of distinct states and that not all states are possible. For example, there are five energy levels for the hydrogen atom, each of which requires a very specific photon energy. There is nothing random about this.
There are infinitely many energy levels for the hydrogen atom. The levels just get closer and closer in energy as the quantum number increases. Almost all of the interesting photophysics involves the first few levels, but that doesn't mean that the others don't exit.
The random universe assumption assumes everything has a finite probability, which is not the case in a quantum universe.
The random universe assumes everything possible has a finite probability (everything impossible has probability of 0).
A quantum universe has 1.0 or 0.0 odds; on or off.
That is not my understanding of things. A substantial amount of QM is centered around the notion of probabilistic events, where the odds of each outcome are somewhere between 0 and 1.
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There are no quantised states for the kinetic energy of a free particle. A photon can have any energy.
There are only 6 sides to a cube, but dice games are entirely probabilistic.
If you look at the first five energy levels of a hydrogen atom, which are quantitized, this each isbased on a causal corresponance between energy level and energy quanta. You cannot use random energy quanta; roll the dice, and expect each level to appear with with fixed odds. This is not how it works.
Random seems contradictory. In the hydrogen atom example, quanta are very specific. Instead of dice it is more like loaded dice, that always comes up the same each throw.
When systems get more complicated what we have may be more like throwing ten loaded dice, while not knowing which are which. This could appear random to someone unaware they are all quantum loaded.
If you were looking at a gas, we can't keep track of each and every atom. It is easier to apply the assumption of random. But again only individual quantum events can happen which are causal in nature.
What appears to have happened is the random tail wags the quantum dog. This has created a relative reference illusion
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our universe is quantized
There has not been a demonstration that time is quantized.
It is possible that time is quantized, but if so, it is on such short timescales that we can't detect it yet.
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What you seem to be suggesting is a predestined universe in where what we call a probability in fact is a result of hidden variables?
Would that be correct PP?
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A quantum universe implies that there are only a finite number of distinct states and that not all states are possible.
That's incorrect. Quantum physics does not say that everything is quantized. In fact the energy of a free electron is not quantized at all. The only time that the energy of a particle is quantized is when the particle iss moving in a potential well. So your assertion that there is only a finite number of states possible in the universe is quite incorrect.
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The assumption of randomness is due to unpredictability of particles behaviour at the atomic scale. This is implicit in the equations of Quantum Mechanics. Is randomness a fundamental property of the universal laws? The answer is just an interpretation until a more complete theory includes Relativity, gravity and all other "forces" in a unified form. I would say if the universe is infinite, randomness is inherent, if not then no. But it is an interpretation...
The assumptions must be questioned when the evolution of science stalls.
Pete, I think that from a QM point of view, the free electron must be quantized but its proper energy is unexplained. If you add Relativity, it is not determined yet. From a purely relativistic point of view, it is not quantized.
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Could the electron have a varying charge, according to how fast it moves? I mean if it goes through a copper wire, won't the resistance of the wire slow it up.
This should make it lose energy.
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Could the electron have a varying charge, according to how fast it moves?
No, charge is invariant
I mean if it goes through a copper wire, won't the resistance of the wire slow it up.
Yes, the electrons can be thought of as bouncing into one atom after another, like in a pinball machine, slowing them down, but the electric field (provided by the battery) accelerates them again until another collision. The effective speed they flow through the wire, known as electron drift, is quite slow.
This should make it lose energy.
They do, as heat, but remember the battery or generator is providing the energy to keep them moving.
The above is a fairly crude explanation of what is happening, but I hope it gives the general idea.