Interactions Definition and 291 Threads

  1. neomahakala108

    Question about Energy Interactions.

    is it true that: 'as energies interact, they change properties, possibly creating massive matter in the process or vice versa' ?
  2. ChrisVer

    Exploring Neutralino Interactions: Amplitude Analysis and Source Check

    Do you have any source where I can check for the neutralino (higgsino or chargino/bino -like) interaction processes? In general I'm trying to find the amplitudes in the Appendix A of: http://journals.aps.org/prd/abstract/10.1103/PhysRevD.47.376 But without seeing a Lagrangian, I can't...
  3. R

    Neutrino Interactions: Z Boson, Electron & Beyond

    When the Z boson is around can a neutrino interact with a particle other than an electron? And how does the neutrino find the electron if the neutrino is neutral and does not interact electromagnetically?
  4. R

    Navigating Social Interactions in High School

    So basically I'm wondering if any of you guys find small talk annoying. I'm still in high school, where interpersonal relationships are becoming more complex and 'formal'. Personally I find it really contrived, as I'm used to engaging in some activity with others before conversation naturally...
  5. ChrisVer

    Difference between 2to2 interactions

    What is the difference between these interactions? a+b \rightarrow c+d and b+a \rightarrow d+c ? I was reading the "State-of-the-art formulas for helicity amplitude calculation and all that" ver 2.4, part Ia. - Spherical-vector method for helicity amplitudes (Formalism), by Ken-Ichi...
  6. F

    Bosons and Fermions in a One-Dimensional Infinite Potential Well?

    Homework Statement A particle of mass m is confined to the region |x| < a in one dimension by an infinite square-well potential. Solve for the energies and corresponding normalized energy eigenfunctions of the ground and first excited states. (b) Two particles are confined in the same...
  7. G

    How do different materials interact with light?

    Could someone please clear this up for me. We have, Reflection (metal, mirror) Reflection (colour) Absorption (heat) Emission (heat) Transmission (glass) Sry but I use photoelectric effect to reference electrons absorbing photons of specific energies to be excited to higher energy levels, I...
  8. S

    Deriving sound from simulated interactions

    Hi all, First, I hope this is in the right place, apologies if it isn't. I'm looking into the possibility of deriving sound from the simulated actions of simple bodies in a 3D space. As a toy example of my aim, I hope to be able to compute the sound that would be generated by a metal...
  9. J

    Radius of effect of atomic interactions

    Suppose that I have an atom in one corner of a room, and I fire a photon toward the opposite corner (and assume that it is absorbed there into the wall). There is essentially zero probability that that photon will interact with the atom (either be captured, or stimulate emission, or whatever)...
  10. S

    Laser Gain Medium Interactions

    I have a diode laser that emits multi-mode light. Two frequencies of this light are selected in an external cavity and reflected back into the laser diode. The laser diode's gain medium then resonate at these two frequencies and emits dual mode light. The laser operates in the 1550nm region...
  11. A

    Phonon Interactions & Brillioun Zone Mapping

    This occur when two phonons interact and the sum of their momenta add to a new wavevector outside the new Brillioun zone. The resulting wavevector is then mapped back into the Brillioun zone by subtraction of a suitable reciprocal lattice vector. I don't think I understand the physics in all of...
  12. W

    Linear chain with m th nearest neighbor interactions

    [b]1. Ashcroft and Mermin 22.1 Reexamine the theory of the linear chain without making the assumption that only nearest neighbors interact, using the harmonic potential energy of the form: U^harm=∑_n▒∑_(m>0)▒1/2 K_m [u(na)-u([n+m]a) ]^(1/2) Show that the dispersion relation must be...
  13. B

    Wave functions for 2D potential with spin interactions

    So consider a 2D system with a circular potential and a spin-orbit interaction: V(r) = V_0 \theta(r_0 - r) + c r_0 V_0 L_z S_z \delta(r-r_0) where θ is step function. So the operators Lz and Sz commute with the Hamiltonian are are therefore conserved quantities. For the same reasons...
  14. E

    How Does a Proton's Speed Affect Coulombic Impulse on an Electron?

    Homework Statement A high-speed proton of electric charge e is modeled as moving with constant speed v past an electron of mass m and charge −e initially at rest. The electron is a distance α from the straight-line path of the proton and we assume it ‘scarcely moves’ while the proton comes...
  15. V

    Photochemistry and Dipole-Dipole interactions

    Let me begin by saying that this question had a disclaimer, saying that part a should NOT be done exactly, but in a back of the napkin manner. The idea is to make reasonable assumptions and approximations in order to obtain an answer. Homework Statement Suppose that a certain chemical...
  16. M

    Is weak isospin conserved by all interactions?

    Hi people: I keep reading one day that weak isospin is exactly conserved by all interactions; other days that sometimes weak isospin is *not* conserved. Can anyone clear this one up?!
  17. E

    A few questions about wave interactions (conceptual, not technical)

    Suppose there are two spheres freely floating on the surface of an infinitely large and deep body of water. Suppose these two spheres bob up and down independently and create waves (which may or may not have the same frequency and amplitude) in the water. Do these spheres always remain...
  18. L

    How do I calculate the potential and electric field between two dipoles?

    Hi everyone, we haven't discussed this topic in our lecture but this task could be in the final exam so I'd need some help with it. Homework Statement Two dipoles with the dipole moment p are given. The distance between these two is d. Find the potential as well as the electric field from...
  19. B

    Helicity interactions of the Z0

    The Z0 is a linear combination of W0 and B0 bosons, so unlike the charged current interaction it can interact with both handednesses (is that a word). In the search to quantify this mixing, people measured the cross section for muon (anti)neutrinos to scatter off electrons. This is a reaction...
  20. sunrah

    Quark-antiquark creation in strong interactions

    (please note this is similar to a homework question I have posted but it is not the same and here I am just trying to understand a concept) In a book I was reading it said \Delta^{+} \longrightarrow n + \pi^{+} is a viable process via the strong force because all that is needed is a down...
  21. N

    Can Radio Waves Change the Electric or Magnetic Properties of Metals or Liquids?

    So mobile devices use radio waves so I had this thought that if there was evidence linking radio waves with changing organic tissue structure is the evidence that radio waves can be used to change the electric or magnetic properties of metals or liquids? Underwater walk talky jabbering for...
  22. C

    Hyperfine Interactions: What, How & Cs-133

    what is hyperfine interactions? how is it related to hyperfine transition in Cs-133 and atomic clocks?
  23. Y

    Harmonic vs Anharmonic Interactions in Lattice

    I am currently working my way through Kitel's Solid State Physics book. When discussing the consequences of the harmonic assumption (quadratic degree of freedom for interatomic lattice interactions), he states that 1) the lattice waves do not interact 2) a single wave does not change form...
  24. S

    Semiconductor Electromagnetic Wave Interactions

    Greetings everyone, I need information about how semiconductor interacts with electromagnetic radiation, the absorption, scattering, transmission and reflection properties of semiconductors. I also need to associate this information with free charges or bound charges. I would be grateful for...
  25. T

    Changing the chirality of fermions in interactions with Higgs

    Am i correct when i say that the fermions get a mass and interaction term with the Higgs from the SU(2)_{L}\times U(1)_{Y} invariant Yukawa interaction -g_{y}\bar\psi_{L}\phi\psi_{R} - g_{y}\bar\psi_{R}\bar\phi\psi_{L} where \psi is the fermion field and \phi the Higgs field. My...
  26. Greg Bernhardt

    Intro Physics Matter and Interactions by Chabay and Sherwood

    Author: Ruth W. Chabay (Author), Bruce A. Sherwood (Author) Title: Matter and Interactions Amazon Link: https://www.amazon.com/dp/0470503475/?tag=pfamazon01-20 Prerequisities: Contents:
  27. M

    Weak Interaction-QED Interactions

    Well, I was looking at the beta decay of neutron, and I thought that the weak interaction can be seen in analogue to QED, where you have an electron that emits(or absorbs) a photon and gets scattered. In the same way, couldn't we say that a Neutron is scattered to a Proton (I see them as the...
  28. P

    Higgs - interactions and forces; distinction between these?

    Higgs --- interactions and forces; distinction between these? At the moment I'm reading Lisa Randall's Knocking at Heavens Door, and I have a quick question that can no doubt be easily answered. I've often read and accept that there are four forces of Nature: Strong, Electromagnetic (EM)...
  29. P

    What are some different interactions where photons are released?

    Pretty simple; what are some different ways that photons are released? Specifically, I'm looking for a short list of different particles that will release a photon in any given interaction. Tried googling, but its amazing how difficult it is to find an answer to such a simple question --...
  30. K

    Photon-Photon Interactions: What Determines Pair Production vs. Scattering?

    When two high energy photons collide with each other, what determines whether a pair production results or whether a photon-photon scattering results? I hope my question makes sense.
  31. 1

    Some fundamental questions on light matter interactions

    Hi there, I've a few (probably very basic) questions about photon-electron (light-matter) interactions. Here we go: 1) How can an electron "understand" that the frequency of incoming photon is equal to its excited state and so absorb that. Is there any "virtual" resonance between the...
  32. E

    Higgs boson interactions and gravitons

    How is it possible that the Higgs boson interacts with itself? Now that it is almost certainly discovered, how can a particle that gives mass to other particles, give mass to itself? Does it make a 'loop' with other Higgs bosons? How can the Higgs boson interact with other particles in such...
  33. mishima

    EM field and wave interactions of a point charge

    I've been thinking of 2 point charges separated by some distance in static equilibrium. When one charge is moved from rest, the EM field would change the way it looks at the location of the other point charge. This "changing in the looks" of the EM field as I understand propagates from the...
  34. V

    Change of the Del operator in two particle interactions

    Change of the "Del" operator in two particle interactions Ok,so John Taylor's Classical Mechanics has this small subtopic "energy interactions between 2 particles".And,in that,hes defined a "del1" operator as the vector differential operator with respect to particle 2 at the origin.Hence,the...
  35. N

    Do we need to refer all interactions to symmetries?

    Do we innevitably need to attach each interaction with a symmetry?Could we contruct a theory of an interaction without using any symmetry theory(example gravity interaction)? Why do we not need to demonstate QCD being renormalized,but we must demonstrate electroweak theory is renormalized(I...
  36. M

    Exploring the Role of Pi Interactions in Cyclic Aromatic Molecules

    hello! why a cyclic aromatic molecule forms pi interactions, while a cyclic aliphatic (with single only carbon bonds) doesnt? thanks!
  37. L

    Indirect exchange interactions Fourier transforms

    ##\hat{c}_{i\sigma}=\frac{1}{\sqrt{N}}\sum_{\bf{q}}e^{i\bf{q}\cdot \bf{R}_i}\hat{c}_{\bf{k}\sigma}## ##\hat{c}^+_{i\sigma}=\frac{1}{\sqrt{N}}\sum_{\bf{q}}e^{-i\bf{q}\cdot \bf{R}_i}\hat{c}^+_{\bf{k}\sigma}## Then ##-J\sum_{i}\hat{S}_i^z\hat{c}^+_{i\sigma}\hat{c}_{i \sigma}## in...
  38. D

    Heat Interactions with Non-Normal Matter

    So I saw another post asking about heat interactions in a vacuum, and it got me to wondering: is there any significant interaction of heat with non-normal matter, such as dark matter, anti-matter, and strange matter. I would assume the heat interaction with anti-matter would be pretty much the...
  39. S

    Question on electromagnetic interactions

    Hello all, I have a question relating to charge. I understand that when a positive charge is near a negative charge it creates an attraction. This attraction is explained by the electromagnetic force and by the exchange of electrons. My question is this, how can a new particle such as a photon...
  40. C

    What Is ATP's Phosphate Energy That Powers All Cellular Interactions?

    Hopefully someone can assist me here as I've searched the internet (google searches, wikipedia, youtube videos) in vain for this answer and yet I'm still stumped about just what is the actual ''energy'' being transferred from when after ATP leaves the ETC and then binds with a receptor...
  41. O

    Strong and weak interactions particles

    Does anybody could help me to state if the following particles experience strong interactions, weak interactions, both interactions or neither of the two interactions? This is what I think: electron = strong interactions and weak interactions boson = weak interactions down quark = strong...
  42. K

    Interactions between Photons and Atoms in the Electromagnetic Spectrum

    If photons have a quanta of energy tied to its frequency, and the energy state of an atom can only be at specific levels, does this mean that atoms will only interact with certain wavelengths of light? As an example, hydrogen emits a photon with a wavelength of 486 nm in one of its state...
  43. L

    Phonon-photon interactions: guidelines needed

    Hi! I'd really need someone to tell me if I'm on the right track here. What I need to do is a research on electromagnetic radiation-matter interactions, based on phonon-photon interactions. Does this include any of the following: photoelectric effect, Compton scattering, Rayleigh scattering...
  44. F

    Meson vs. Baryon: Quark Interactions and Fermions/Bosons

    Mesons are bosons, while the baryons are fermions. My question is, meson is a type of hadron that made from the interaction of quark with gluon. Quark is fermion, not boson. so why mesons are boson?
  45. H

    Calculating partial charges for interatomic coulombic interactions

    I want to understand how to compute (or find a database for) partial charges, which I can then apply to calculating coulombic interactions. From http://www.chemaxon.com/marvin/help/calculations/charge.html, it is said that electronegativity is related to the partial charge by a quadratic...
  46. S

    Microwave interactions with motion sensors

    Hello everyone here at the physics forum. Forgive me if I am not posting this question in the correct forum. I am not a physicist, but I do know my way around a little bit. Now on to my question. I am a security consultant who conducts security audits and specializes more specifically in...
  47. N

    Weak interactions: I know why they're weak, but why are they slow?

    Compared to, for example, electromagnetic interactions. Are the "weakness" and "slowness" perhaps somehow related? Perhaps both "weakness" and "slowness" can both be reformulated as "having a low probability of occurring", making the "slowness" apparent, and making the "weakness" a...
  48. O

    Conservation of Strangeness (outside of strong interactions)

    I realize that strangeness must only be conserved in strong interactions, but if strangeness is conserved, must it be a strong interaction?I'm an A level student so please go easy.. mention spin, colour, charm, top or bottom and I'll know not where to look.
  49. J

    2 and 3 Phonon Interactions, whats the difference?

    I am doing a basic introduction to solid state physics and I have come across a question which asks What the difference between two phonon interactions and three phonon intereactions. I know that Normal colission and Umklapp colissions are part of the three phono interactions since it tells me...
  50. I

    Classifying interactions by force

    What are the general features you should look for when classifying an arbitrary particle interaction according to strong, weak, or electromagnetic forces? Cheers
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