An atom is a collection of excitation fields

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• An atom can be understood as a system of excitation fields, where electrons can absorb energy and move to higher energy levels, becoming excited, and then return to lower levels, releasing energy.
• The excited state of an atom represents an electron jumping from its original energy level or orbital (also called the ground state) to an empty orbital of a higher energy shell that is further away from the nucleus. The energy absorption causes the excited state.

• Excited State and Emission: The excited state of an atom represents an electron jumping from its original energy level or orbital (also called the ground state) to an empty orbital of a higher energy shell that is further away from the nucleus. The energy absorption causes the excited state.
• However, the excited electron does not stay in the excited state permanently but returns to the ground state by emitting
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• Electron Cloud Definition and Appearance, An electron is a subatomic particle with a negative charge. The electron cloud refers to the region around the nucleus of an atom where electrons are most likely to be found. It is spherical in shape and stretches in all three directions from the nucleus. It is not evenly colored and the color gradient represents electron probability, meaning there is the likelihood of finding an electron in a certain location.

Excited State and Emission, The excited state of an atom represents an electron jumping from its original energy level or orbital (also called the ground state) to an empty orbital of a higher energy shell that is further away from the nucleus. The energy absorption causes the excited state.

However, the excited electron does not stay in the excited state permanently but returns to the ground state by emitting light. When the electron falls from the excited state, it loses energy in the form of light. This process is called emission.   .

• The excited state plays a role in various chemical reactions, such as photosynthesis. Ultraviolet light from the sun excites electrons in chlorophyll and results in the transfer of excited state electrons that drive photosynthesis.
• Another important role of the excited state is in substance analysis. The excited electrons of heated objects emit light as the electrons return to their ground states. The color of light can be very distinctive, and this is very useful in identifying the presence of certain substances. For example, green flame in the flame test indicates the presence of copper.
• Atoms and Energy Levels: Atoms consist of a nucleus (protons and neutrons) and orbiting electrons.  These electrons occupy specific energy levels or orbitals around the nucleu
• Quantum physics has revealed a profound paradox: Matter, which is 99.9999% empty space, presents itself as solid. This captivating contradiction prompts us to ponder: How does matter manifest solidity? My grasp of the quantum theory of matter, spanning nonrelativistic and relativistic quantum mechanics and relativistic quantum field theory, is thorough and well-founded. It is genuinely news that “quantum physics has confirmed that matter is composed of 99.9999% emptiness.” If anything, my studies suggest the opposite: true emptiness does not exist, not even in the deepest of space in the large voids between galactic superclusters. The standard depiction of atoms as tiny nuclei with even tinier electrons orbiting them, akin to a miniature solar system, is a gross oversimplification that does not accurately represent the true nature of matter. Understanding these misconceptions can be enlightening and informative. What exactly is an electron? It is most accurately described as an ‘excitation of the electron field.’ While this may be a complex concept for those new to the theory, I will simplify it for you to ensure you feel informed and knowledgeable. In our most comprehensive theory, quantum field theory, everything originates from a set of fields: the electromagnetic field, the field of electrons, fields of quarks, gluons, vector bosons, and the Higgs field, all interacting and exchanging energy. These fields are omnipresent, connecting us to the very fabric of the universe. When they interact, they may gain units of energy that we sometimes call ‘excitations.’ As a result of an interaction, the electromagnetic field may gain a unit of energy called a photon. Under the right circumstances, this electromagnetic field excitation may appear highly localized. However, under different circumstances, it may not be localized at all. Either way, this photon is not some miniature cannonball but a property of the electromagnetic field in a given state. The same goes for the field of electrons and all the other fields of the standard model. An atom is a collection of excitations of the field of electrons, fields of quarks, fields of gluons, and the electromagnetic field in a specific configuration. It is neither empty nor full of anything. It is localizable. We can localize an atom by interacting with it. The more powerful the interaction, the more precisely it nails down the atom’s location, though there are limits. Interact with that atom too powerfully, and you break the configuration, “smashing” the atom.With the right experimental design, which often involves powerful particle accelerators or sophisticated microscopy techniques, it is also possible to interact directly with constituent parts of that atom. Moreover, they can indeed be confined by interactions with tiny regions. This inspires the intuitive but ultimately false picture that the atom consists of small, miniature cannonballs separated by space. No: The atom is a configuration of interacting fields.

• An excitation that corresponds to a genuinely elementary particle, like an electron, can be confined to an arbitrarily tiny volume of space. So, the electron has no size. In contrast, composite things like atoms, or the protons and neutrons therein, have a minimum size that is, roughly speaking, determined by the nature of interacting fields and excitations that constitute the object.Now, as to why matter appears solid… However small or big, atoms make no difference. What matters is that atoms, though electrically neutral overall, have a charge distribution that is never perfectly symmetric or uniform. When you try to bring atoms together, they might stick together, forming a molecule, or repel each other due to their electromagnetic properties. All this occurs over much greater distances than the sizes we associate with the atom or its constituent bits. So when you find, say, that you cannot push your hand through a solid wall, electromagnetic interactions between the molecules of your body and the molecules of the wall occur, primarily as their electron “clouds” get close to one another and electrostatic repulsion kicks in. Without interactions, there would be no resistance.
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