Why is Mass-Energy Concentrated in Atoms, Solar Systems & Galaxies?

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In summary, the conversation discusses the concept of empty space in atoms, solar systems, and galaxies, and the concentrated mass-energy on different scales. The Bohr model of the atom is mentioned as an explanation for the size of electron orbitals, and the concept of resonant frequencies is used to explain the size of atoms. The conversation also mentions the role of gravity in larger scales and the estimated weight of subatomic particles. The reason for the smaller size of subatomic particles compared to the Bohr radius is unknown.
  • #1
Ratzinger
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Why is there so much empty space in atoms, in solar systems or between galaxies?
Why is mass-energy always so concentrated on all these different scales?
 
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  • #2
Why is there so much empty space in atoms, in solar systems or between galaxies?
Forces.

Why is mass-energy always so concentrated on all these different scales?
I don't understand.
 
  • #3
Ratzinger said:
Why is there so much empty space in atoms, in solar systems or between galaxies?
Why is mass-energy always so concentrated on all these different scales?

regarding atoms, particularly the Bohr model (which is not as accurate as the quantum mechanical model of the H atom), is that electron orbitals have to be as large as they are for the electron's (deBroglie) wave function to have an integer number of cycles going around the orbit.

that is just like the resonant frequencies of a circular pipe. only frequencies where, for each time a sound wave or electron's wave goes around the circuit, the wave function is at the same phase (so as not to cancel the wave from other cycles before or after) of the waves for the other trips around the circuit, only waves of those frequencies will survive the out-of-phase "destructive interference". or stated more simply, only waves with wavelengths that are the circumference divided by an integer number, only those waves will have constructive interference. those waves will team up.

the smallest such circumference in the H atom is [itex] 2 \pi [/itex] times what is called the Bohr radius [itex] a_0 = \frac{m_P}{m_e \alpha}l_P [/itex] and it's about half an angstrom. it defines the ballpark of how big atoms are.

that doesn't explain why the subatomic particles, the neutrons and protons and electrons etc., are so much smaller than the Bohr radius. that i do not know. we could appeal to the anthropic principle, i s'pose.

r b-j
 
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  • #4
Gravity on both counts for scales larger than solar systems.

Claude.
 
  • #5
I read in some book that if one was to put all the electrons, protons and neutrons together a 1 cm^3 would weight about 10 milion tons.
 

1. What is mass-energy and why is it concentrated in atoms, solar systems, and galaxies?

Mass-energy is a term used to describe the two forms of energy that are interchangeable - mass and energy. This concept is described by Einstein's famous equation E=mc^2, where E represents energy, m represents mass, and c represents the speed of light. The reason mass-energy is concentrated in atoms, solar systems, and galaxies is because of the strong force of gravity that holds these structures together. This force is responsible for pulling matter together and creating a concentrated mass of energy.

2. How does the concentration of mass-energy in atoms, solar systems, and galaxies affect our daily lives?

The concentration of mass-energy in these structures has a significant impact on our daily lives. For example, the energy released from the fusion of atoms in the sun provides us with heat and light, which is essential for life on Earth. The gravitational pull of the moon and other planets also affects Earth's tides and rotation, which have a direct impact on our daily activities.

3. What determines the amount of mass-energy in an atom, solar system, or galaxy?

The amount of mass-energy in an atom, solar system, or galaxy is determined by the amount of matter present and the strength of the gravitational force. In atoms, the number of protons, neutrons, and electrons determines the mass-energy. In solar systems and galaxies, the total mass of all the objects within them, such as stars and planets, determines the amount of mass-energy.

4. How does the concentration of mass-energy in the universe contribute to its expansion?

The concentration of mass-energy in the universe plays a crucial role in its expansion. The gravitational force between objects causes them to attract each other, which can lead to the formation of larger structures like galaxies. However, the expansion of the universe is also driven by dark energy, a mysterious force that counteracts gravity and causes the universe to expand at an accelerated rate.

5. Could there be other forms of energy besides mass-energy in the universe?

While mass-energy is the most prevalent form of energy in the universe, there are other types of energy that exist, such as kinetic energy, thermal energy, and electromagnetic energy. However, these forms of energy are all ultimately derived from mass-energy. Some theories also suggest the existence of dark energy and dark matter, which are currently not fully understood but could potentially be other forms of energy in the universe.

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