By this we mean that only certain wavelengths, and hence frequencies, are emitted. This is called a line spectrum. This is discussed in more detail later in this chapter. Figure 3. Emission spectrum of oxygen. When an electrical discharge is passed through a substance, its atoms and molecules absorb energy, which is reemitted as EM radiation.
The discrete nature of these emissions implies that the energy states of the atoms and molecules are quantized. Such atomic spectra were used as analytical tools for many decades before it was understood why they are quantized. It was a major puzzle that atomic spectra are quantized. Some of the best minds of 19th-century science failed to explain why this might be. Not until the second decade of the 20th century did an answer based on quantum mechanics begin to emerge. Again a macroscopic or classical body of gas was involved in the studies, but the effect, as we shall see, is due to individual atoms and molecules.
How did scientists Figure out the structure of atoms without looking at them? Try out different models by shooting light at the atom. Check how the prediction of the model matches the experimental results. Skip to main content. Introduction to Quantum Physics. Search for:. Explain why atomic spectra indicate quantization.
What is quantized field? What is quantization theory explain? What properties are quantized? Why are fields quantized? What are some examples of things that are quantized? What does it mean when a photon is quantized? What does Quantised mean? How is light quantized? Why does quantized mean? What does it mean for something to be quantized quizlet? Which of the following describes something that is quantized? What color has the greatest frequency? And has no trouble passing one off as the other.
Sources which ironically state that these matters are still theoretical. Theories are the closest thing that science has to laws, there has been mountains of evidence that the theory of general relativity is correct but it is still just a theory. They would just ban you for crackpottery, but this science forums is a bit more relaxed. It seems the answer is not known so I am leaning toward the fact the universe is not infinite in my opinion, once a theory of quantum gravity is proven there will be a answer just wait for it omnifarious.
We long for a caring Universe which will save us from our childish mistakes, and in the face of mountains of evidence to the contrary we will pin all our hopes on the slimmest of doubts. God has not been proven not to exist, therefore he must exist.
The empirical knowledge we obtain through the scientific process is quite different from ontological knowledge, which is that obtained through the study of concepts such as existence, being, becoming, and reality. The point is, scientific investigation, in itself, does not make determinations about the true nature of reality, whatever that may be.
Even if science was to say that all phenomena can be quantized, that only means that experimental results are consistent with such a model. It certainly does not mean that we know beyond any doubt that all phenomena really do exist in discrete packets, or quanta. It helps to remember that no matter how useful and effective such models may be, they are still just models.
It may be tempting to assume the models are one and the same as reality, but the true nature of reality may be something that we humans can never quite apprehend, and the best we can ever do is create better and better models. I'm not sure if I ever thought about science like that.
I suppose I thought it was like a compendium of absolute truths. Science does not deal in absolutes. The whole scientific process is based upon criticism, open-mindedness and accumulation of new evidence that either supports or refutes hypotheses and theories of the natural universe.
Instead of always trying to make facts fit the hypothesis, I often reverse the question and try to discover what happens then. In mathematical physics , the concept of quantum spacetime is a generalization of the usual concept of spacetime in which some variables that ordinarily commute are assumed not to commute and form a different Lie algebra. The choice of that algebra still varies from theory to theory. As a result of this change some variables that are usually continuous may become discrete.
Often only such discrete variables are called "quantized"; usage varies. The idea of quantum spacetime was proposed in the early days of quantum theory by Heisenberg and Ivanenko as a way to eliminate infinities from quantum field theory. The germ of the idea passed from Heisenberg to Rudolf Peierls , who noted that electrons in a magnetic field can be regarded as moving in a quantum space-time, and to Robert Oppenheimer , who carried it to Hartland Snyder , who published the first concrete example.
Yang in the same year. Because of the Heisenberg uncertainty relations, greater energy is needed to probe smaller distances. Ultimately, according to gravity theory, the probing particles form black holes that destroy what was to be measured.
The process cannot be repeated, so it cannot be counted as a measurement. This limited measurability led many to expect that our usual picture of continuous commutative spacetime breaks down at Planck scale distances, if not sooner If we recognize that all matter consists of distinct values sometimes variable there is only one possible conclusion, i. Quantization and Mathematics would not, could not work in analyzing the mechanics of a smooth continuous spacetime. Actually I thought science is absolutely about absolutes, they are exactly what it deals in.
Saying that things are this way or because of this and that's the end of it. That scientists are supposed to be sceptical and reject any kind of paranormal or supernatural explanation without even considering it. That's why I can't imagine how scientists can be religious.
I remember when I was a child, I saw a cartoon where a scientist says "I don't believe in fairy tales, only in scientific facts. That's what being a scientist is all about. For example, consider the answer given by Trimok to this question: physics. So it makes the levels of the hydrogen atom, for instance, a result of pure wave mechanics.
But what makes the occupation quantized then? Is it of similar essence as a bound state? As they are linear combinations of solutions they are also solutions. So at least for the free particle I should have a continuum of normalizable solutions.
See the discussion around line 2. Show 5 more comments. Active Oldest Votes. No, this is not due to boudary conditions. Now, you may have different representations for these operators. Improve this answer. Trimok Trimok I have a hard time seeing the non-commutative operators as a fundamental thing. Can't you derive it from something else? Meaning that the particle can only be at discrete locations. Isn't it an interpretation with a discrete space? You have to choose postulates. However, there are different formulations of quantum mechanics.
A more fundamental formulation of quantum mechanics is using path integrals. Also, it is a kind of historical point of view.
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