# Tag Info

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Does the fact that protons and neutrons have larger mass than electrons mean they're bigger in size? No. The electron and muon are both believed to be "point-like" (which really means smaller than we can measure" despite having $\frac{m_\mu}{m_e} \approx 200$. That is not to say the proton isn't bigger---it is---but that mass does not imply size in any ...

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To begin with electrons are not composite. It is baryons and hadronic resonances that are composites of quarks. Hadrons are held together by the strong forces between quarks. These forces, in contrast to the electromagnetic ones which fall with distance as 1/r^2 (and thus allow us to detect free electrons, whose potential falls like 1/r), they behave ...

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An elementary particle is not like a billiard ball at a very small scale. You yourself state i know sometimes it behaviors like a wave, but it sometimes can be seen as a particle. This statement does not apply to macroscopic particles, it applies to microscopic quantum mechanical entities when the dimensions become equal or smaller than a billionth ...

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How is it possible to see/detect a probability density wave ? It isn't possible. The image is a visualization of an interference pattern from which the nodal structure of the orbital can be inferred. From a Physics World article: In the new work, Aneta Stodolna, of the FOM Institute for Atomic and Molecular Physics in the Netherlands, along with ...

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I think you are correct in being confused. The earth's magnetic field, or any external to the atom magnetic field , can distort orbitals but is not the creators of them. Orbitals are the locus in space where the probability of finding an electron is large enough to be measurable. In the quantum mechanical framework orbitals play the role orbits have in ...

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A nanoscope in the sense you're talking about would be physically impossible, because things which are smaller than the wavelength of light don't reflect light. They do scatter light, but that's a different process which doesn't form a coherent image. Visible light has wavelengths between about 400 and 700 nanometers, so anything smaller than that - ...

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In contrast with the previous incorrect answers that I hadn't noticed, there isn't any ambiguity or confusion about the Bose-Einstein or Fermi-Dirac statistics for composite systems such as atoms. A particle – elementary or composite particles – that contains an even number of elementary (or other) fermions is a boson; if it contains an odd number, it is a ...

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It's really not clear what hypothetical limits you're imposing. I take your question to mean that in the process of baryogenesis the various baryons like protons and neutrons highly favored up quarks (lots more protons than neutrons). Remember, quarks are subject to confinement so other than a quark-gluon plasma, quarks are confined to baryons. Since ...

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The title of this question refers to the emission of light from an incandescent light bulb, and then the body of the question asks for Planck-scale details of the physics happening there. Well, that would be a lot of work to answer. Suppose it's a tungsten filament. Then there's a molecular lattice of tungsten atoms, i.e. a lattice of nuclei surrounded by ...

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When physicists perform particle collisions, they do not execute them one collision at a time. Rather, they perform millions of collisions within very short time frames and they use state of the art computers to analyze and decipher the copious amounts of data they receive. That being said, to isolate a particle such as a proton, it is as simple as ...

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To start answering this question let us talk about a diatomic molecule. In that case we can define the internuclear axis as the z axis in the molecular frame, and talk about the orientation of the various atomic orbitals with respect to that. There is a natural choice of orientation along the bond. For an isolated atom there is no preferred z axis to ...

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They are exactly the same, with the different notations arising in different contexts. You could start with a bunch of helium gas and heat it up or shine UV light on it to turn it into a plasma, and then you'd probably say you have $\mathrm{He}^{2+}$ (or $\mathrm{He}\ \mathrm{III}$ if you are an astronomer). The symbol $\alpha$ is more often reserved for ...

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As far as resolution goes, right now the best in practice are high resolution transmission electron microscopy (which involves firing high energy electrons), high resolution scanning force microscopy (which involves a very sharp tip vibrating above a surface), and the classic scanning tunneling microscopy (which involves conduction through a very narrow ...

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Specific charge is indeed the ratio of charge and mass, but since an atom is made up of neutrals and charged particles, you need to account for them. Thus, you'd use $$\eta=\frac{q\left(n_p-n_e\right)}{n_pm_p + n_nm_n + n_em_e}$$ where $\eta$ is the specific charge (my own variable, don't believe it's standard), $m_i$ is the mass of $i$ (neutrons, ...

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For example, how many quarks are in my brain(easy to find out once you know how many atoms there are)? Actually it's easier to count how many atoms are in your brain than how many quarks are in your brain. As you may know there are three quarks per nucleon in your brain... but this is not the whole truth. The force the binds quarks together creates a ...

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Well, in the case of hydrogen H1, the nucleus (which is nothing more nor less than a proton) can certainly be aligned by a static magnetic field -- said alignment being the basis of proton magnetic resonance, and, not coincidentally, most clinical MRI imaging. I won't venture beyond hydrogen, but that's one example at least.

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Yes. First, we could note that many nuclei possess nonzero magnetic moment. The presence of magnetic field may cause the change in its orientation and realign the nucleus as a whole. This is essentially the basis of Nuclear magnetic resonance. However, the orientation of individual nucleons relative to each other is not changed. Second, we could consider ...

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Conduction of charge has to do with the availability of electrons in the element to conduct charge by physically moving from one place inside the crystal structure of the material to another (that's what current is, movement of charge). Group I-III and transition elements conduct electricity. Moreover, they are solids so there is a high density of atoms per ...

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i know sometimes it behaviors like a wave, but it sometimes can be seen as a particle. Firstly, the electron has a wavefunction $\Psi$, which is a wave, but when it looks like a single point (particle) when it is observed because this wave is actually just the probability amplitude of finding the electron at a certain point, with the probability ...

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This is confusing enough to make me want to scribble down a few equations. This is a creation operator for deuterium: D_{\rho}^{\dagger}\left(k\right)=\sum_{\alpha\beta\gamma}\int\mathrm{d}^{3}l\mathrm{d}^{3}p\mathrm{d}^{3}q\delta^{\left(3\right)}\left(l+p+q-k\right)\ ...

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Actually, there are two different and inequivalent definitions of bosons. On the one hand, they are often defined as particles with integer spin, on the other hand, sometimes they are defined as particles for which only symmetric states exist in nature (see, e.g., Dirac's "Principles of Quantum Mechanics"). Composite particles, such as hydrogen atoms, can be ...

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