Neils Bohr is considered the grandfather of quantum mechanics. If Planck is the father of quantum mechanics, then Bohr must be older than him, which in fact he's not, they're not even related-another strange quantum anomaly.
We're now going to cover three of Bohr's most significant contributions (not all in this section, but the next section as well).
Mindwarps
Did you know that about 1,000 billion (1012) photons of sunlight fall on a pinhead each second? Even when you look at a faint star, your eye receives a few hundred photons from that star each second. And some of them have traveled thousands of light years to get to you.
Having studied the ideas presented by Planck and Einstein, Bohr wanted to theorize about the quantum property of all forms of energy. In order to do that, he would have to explain how energy was released at the atomic level. He went about this by developing a better picture of the atom's structure. The current one that had been developed by Ernst Rutherford needed some tweaking to explain how atoms could emit light and yet not collapse in on themselves. As I hope you remember, light is created when energy is released from matter in the form of electromagnetic radiation. No one really knew how energy was released, they just knew that it was.
Cosmonotes
We've used our imagination and have done some thought experiments to understand some of the theories we've discussed so far. And when it comes to quantum mechanics, we'll also be explaining these theories and concepts through familiar analogies, metaphors, and other images. In most cases, these will suffice to get the ideas involved across even though the theories are much more complex. However, this is the place where many of the physicists began to formulate their understanding of quantum interactions as well. When you're not really sure how something new operates, its often the best way to begin. Remember what Einstein said, "Imagination is more important than knowledge."
In the early 1920s, Bohr came up with a way to understand the stability and exactness of atoms using the analogy of standing waves. You can create your own standing waves by using a jump rope secured at both ends. If you pump energy into it and get it swinging, it can vibrate only in a certain number of predetermined ways. A violin string is another example. It can vibrate in its fundamental frequency, or twice, three times, or four times that frequency-in other words, its characteristic harmonics. It can't vibrate at two and one-half times that frequency. And if you can imagine an electron acting as a wave (remember that electrons can act as either a particle or a wave) within an atom in much the same way, you can see how it would be forced to assume only a certain number of predetermined vibrational states.
Mindwarps
The quantum nature of the universe is not limited to the subatomic world. It seems that some things have to come in whole chunks: children, snowflakes, memories, experiences, paintings, and a whole host of other things. This also seems to embody an irreducible yes/no, on/off quality that lies at the core of computer technology. Cultures, perceptions, beliefs, and even phases of life can often seem discretely separated as individual quantum states, which is why we can feel transformed when we move from one to another.
Let's look at another analogy. Remember our stair analogy discussed previously? Our child can't land safely or remain stable at step two and one-half, or three and one-third. She needs a minimum amount of energy before she can attain the next step or state. If she doesn't have quite enough energy to make it to step four, she'll remain at step three. Atoms, too, act in the same way and will not absorb radiation unless the energy they receive contains the minimum to make the next quantum leap.
A child jumping down stairs also behaves somewhat like an electron changing states within an atom. In this case, she gives off energy to the floor as she jumps to a lower stair or state. But Bohr realized, like Planck and Einstein, that this energy can only come in chunks or quanta. A jump from step four to step two gives off two steps' worth of energy or a jump from step five to step two gives off three steps of energy.
An electron jumping to a lower state gives off its energy in the form of light. A jump from orbit or step five to orbit three might radiate quanta of red light; a jump from six to two might radiate more energy (higher frequency), so it could be a blue light. In terms of other types of electromagnetic radiation, a jump from orbit one to the ground might give off low energy radio waves, while a jump from orbit eight to the ground might give off high energy x-rays. This then was the way that Bohr described the quantum leap and how light was emitted.
But while this theory explained the quantum nature of atoms, some other unusual questions were raised, questions that have now become an accepted characteristic of quantum reality. For example, an electron can't exist between quantum states, not even for an instant. There is no such thing as in between. It's like jumping from one hour to the next without passing through the minutes in between, or disappearing from one end of a room to miraculously reappear at the other end. This quantum leaping in and out of existence can be very unnerving. How does a quantum state mysteriously materialize out of nowhere? How do you get from one place to another without crossing the territory in between?
This unanswerable characteristic is true of the entire microcosmic quantum world. Virtually everything in the subatomic world is quantized. Not only energy and light, but also matter, momentum, electric charge, and many other exotic qualities of subatomic things, such as "strangeness" and "charm" (we'll get to these last two terms when we discuss properties of subatomic particles). An atom has to absorb energy by swallowing it whole and spits it back out in quantum chunks. This means the very stuff of the universe can't be smoothed out past a certain point, it has a grainy, lumpy texture.
So with this first of many unexplainable qualities under your quantum belt, I'll close this section with a quote from Richard Feynman, one of the most brilliant and gifted physicists/teachers of quantum mechanics. He said:
Niels Bohr worked in the field of physics, with a focus on atomic structure and quantum theory. He made significant contributions to the development of the theory of quantum mechanics and is best known for his model of the atom, called the Bohr model.
In formulating his hypothesis, Bohr also considered the experimental evidence of atomic spectra and the quantum theory developed by Max Planck and Albert Einstein. Additionally, Bohr incorporated concepts from classical mechanics and Rutherford's model of the atom to propose his atomic model.
Some key scientists involved in the development of atomic theory include John Dalton, who proposed the atomic theory in the early 19th century based on the idea of indivisible particles; J.J. Thomson, who discovered the electron in the late 19th century; and Niels Bohr, who proposed a model of the atom with quantized electron orbits in the early 20th century.
Niels Bohr is known for developing the Bohr model of the atom, which proposed that electrons orbit the nucleus in discrete energy levels. This model was a key development in the history of quantum mechanics. Bohr's work helped to explain the stability of atoms and laid the foundation for further advancements in atomic theory.
Atomic theory began to develop in the early 19th century with scientists like John Dalton, and continued to evolve through contributions from scientists like Niels Bohr and Ernest Rutherford. The theory of relativity was introduced by Albert Einstein in the early 20th century, with his Special Theory of Relativity published in 1905 and General Theory of Relativity in 1915.
Bohr's Atomic Theory stated that all atoms revolve around the nucleus
Bohr wished to describe the structure of atoms.
Niels Bohr's atomic theory, known as the Bohr model, was proposed in 1913. This theory revolutionized our understanding of atomic structure by introducing the concept of quantized energy levels within the atom.
yes
Niels Bohr developed his atomic theory in 1913. This theory introduced the idea that electrons orbit the nucleus in specific energy levels, which was a major advancement in understanding the structure of atoms.
father atom
Niels Bohr published his atomic theory in 1913...which applied Max Planck's quantum theory to Rutherford's idea of a nuclear structure.... adding the idea of electrons traveling in orbitsaround the atom's nucleus.
An atomic theory that patches up the holes in Ernest Rutherford's own. Bohr's theory states that electrons give off energy in bunches, not continously, so as long as the electrons remain in a stable orbit they will have the same amount of energy.
Niels Bohr is important for his work in the areas of atomic structure and quantum theory. He was a physicist from the country of Denmark.
Niels Bohr proposed his postulations on atomic theory in Copenhagen, Denmark in the early 20th century. His ideas became known as the Bohr model of the atom, which helped explain the behavior of electrons in atoms.
Probably Neils Bohr
Niels Bohr's major contribution to atomic theory was his development of the Bohr model, which described the structure of the atom with electrons orbiting the nucleus in discrete energy levels. This model helped explain the stability of atoms and the spectral lines observed in their emission or absorption of light. Bohr's work laid the foundation for modern quantum theory and the understanding of atomic structure.