question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>What happens when a neutrino and an anti-neutrino interacts together? For example, what does a muon neutrino and anti-muon neutrino produce? it says in my book that it creates "muons and antimuons". But, how? Don't the particle and the antiparticle annihilate when they interact with each other? </p> | g14544 | [
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<p>So if you have a light bulb in a room, and you had a tool to measure the amount of light that's in the room, then let's assume the amount of light only caused by the bulb is "1"</p>
<p>If you place a mirror next to the bulb, does the amount of light in the room in crease to "2"?</p>
<p>Can you keep going so that t... | g14545 | [
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<p>Are the 8 Maxwell's equations enough to derive the formula for the electromagnetic field created by a stationary point charge, which is the same as the law of Coulomb? </p>
<p>If I am not mistaken, due to the fact that Maxwell's equations are differential equations, their general solution must contain arbitrary con... | g14546 | [
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<p>I would like to know which fields in physics have seen growth or benefited by applying <a href="http://en.wikipedia.org/wiki/Quantum_field_theory" rel="nofollow">QFT</a>? I know that approaches to quantum gravity such as string theory use QFT, HEP and also some branches of condensed matter physics. Where is it appli... | g14547 | [
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<p>How can increasing the radius of earth may cause an impact on the solar system ? Like, would earth may start making a bigger orbit (due to increase in size and wait) or vice versa ? or else ?</p>
<p>PS: The base of my question arises from the point of view of "Growing Population", and managing it by "artificially i... | g14548 | [
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<p>Some time ago I was talking to a professor in college about some of the fundamental aspects and origin of General Relativity. I was surprised to learn, in fact, that a pretty good approximation to GR can be achieved simply by using Special Relativity and applying a series of (infinitesimal?) Lorentz boosts to simula... | g14549 | [
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<p>I was going through some of the theory behind <a href="http://en.wikipedia.org/wiki/Zener_diode" rel="nofollow">Zener diodes</a>. I know what they're used to work at constant voltage, but I don't know how they work. Actually, I kind of get that too, I know that voltage is constant until breakdown occurs (avalanche b... | g14550 | [
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<p>Recently I've heard that there exist alternative interpretations of quantum mechanics which, while not as widespread as the Copenhagen intepretation (or so it would seem), are equally valid in the sense that they describe all the observable effects. <a href="http://en.wikipedia.org/wiki/Interpretation_of_quantum_mec... | g14551 | [
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<p>Consider a charged particle in a static electromagnetic field. Suppose that the domain is simply connected so that the second law of Newton's dynamics reads:
$$
m\frac{\mathrm{d}^2\vec{x}}{\mathrm{d}t^2}=-e\left(\vec{\nabla}\Phi+\frac{\mathrm{d}\vec{x}}{\mathrm{d}t}\times(\vec{\nabla}\times\vec{A})\right)
$$
where:<... | g14552 | [
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<p>Normal mode and wavenumber integration methods allow the evaluation of an integral transform solution.</p>
<p>The text book that I am reading states that the normal mode method evaluates the field as a sum of residues for the poles enclosed by the integration contour. On the other hand, wavenumber integration uses ... | g14553 | [
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<p>I've seen many versions of the figure shown below -- the famous <em>Swordy plot</em>. They tend to explicitly point out two features in the CR spectrum, the <strong>knee</strong> and the <strong>ankle</strong>. I know that the source of UHECR's above the <em>ankle</em> is currently a mystery. But I'm having a devili... | g14554 | [
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<p>I am still getting used to the braket notation. Is this manipulation correct?
$$
\frac{-\hbar^2}{2m}\int_{-\infty}^{\infty}\frac{\partial^2\phi_n^*}{\partial z^2}
\phi\,dz = \int_{-\infty}^{\infty}\phi\left(\frac{-\hbar^2}{2m}
\frac{\partial^2}{\partial z^2}\right)\phi_n^*\,dz = \int_{-\infty}^{\infty}
\phi \hat{K}... | g14555 | [
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<p>Does this paragraph make sense?</p>
<p>"The vector potential emitted by a current carrying wire is a packet of
coherent virtual photons, all with the same momentum traveling in
the same direction. They cannot annihilate each other, for this would
violate conservation of momentum. They travel to infinity. Momentu... | g14556 | [
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<p>How do we determine how much the surface of the Earth deflects due to <a href="http://en.wikipedia.org/wiki/Tidal_forces" rel="nofollow">tidal forces</a> from the Moon (and Sun)?</p> | g14557 | [
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<p>I have heard that communication using mobile phones begins to degrade when used on a vehicle moving at speeds above 200 km/hr due to <a href="http://en.wikipedia.org/wiki/Doppler_effect" rel="nofollow">doppler effect</a> as described <a href="http://ptgmedia.pearsoncmg.com/images/art_sklar6_mitigating/elementLinks/a... | g14558 | [
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<p>In standard (non-Wilsonian) renormalization we split the bare Lagrangian $\mathcal{L}_0$ into </p>
<ul>
<li>a physical Lagrangian $\mathcal{L}_p$ with measurable couplings and masses </li>
<li>counterterms $\mathcal{L}_{ct}$ with divergent couplings</li>
</ul>
<p>We then calculate with the bare Lagrangian perturba... | g14559 | [
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<p>If I press on something, it presses me back with the same force. if I press a pillow with my fist, l do not feel pain but if I press a rock with my fist with the same force, I do feel the pain. why?</p>
<p>Regardless of the fact that my force gets distributed over the pillow surface, I should still get a reacti... | g14560 | [
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<p>People often talk about <a href="http://www.google.com/search?q=%22particle+hole+symmetry%22" rel="nofollow">particle-hole symmetry</a> in solid state physics. What are the exact definition and physics picture of particle-hole symmetry? How to define the density of particles and holes?</p> | g14561 | [
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<p>From <a href="http://en.wikipedia.org/wiki/Energy_Catalyzer" rel="nofollow">Wikipedia</a>:</p>
<blockquote>
<p>The Energy Catalyzer is an apparatus built by [...] Andrea Rossi, [and] Sergio Focardi. The 2009 patent application claims "a method and apparatus for carrying out nickel and hydrogen exothermal reaction... | g14562 | [
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<p>Dark energy physically can be interpreted as either a fluid with <em>positive</em> mass but pressure the negative of its density (pressure has units of energy/volume, and energy is mass), or a property of space. If it's a fluid, it should add to the mass of black holes like any form of energy (no hair), and the blac... | g14563 | [
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<p>To an an external observer it appears that time has stopped for photon. But this relation is reflexive, so for an observer travelling with the photon it appears the universe has stopped everywhere.</p>
<p>Is this right?</p>
<p>Space also gets distorted parallel to the direction of motion, but not perpendicular to ... | g361 | [
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<p>This is kind of a continuation of <a href="http://physics.stackexchange.com/questions/60566/dimensional-regularization-and-ir-divergences-and-scale-invariance">this</a> and <a href="http://physics.stackexchange.com/questions/53768/defining-a-cft-using-beta-functions">this</a> previous questions. </p>
<ul>
<li><p>S... | g14564 | [
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<p>If you wanted to at least semi-realistically model the key components of Human running, what are the factors that determine the top running speed of an individual? The primary things to consider would be the 'thrust' provided by the legs, with significant components in the vertical and horizontal, and also wind resi... | g14565 | [
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<p>My son's science project involves liquifying air. I found the Linde process which is the way it was done first. We are trying and not getting very far so I am looking for advice.</p>
<p>I have an air compressor good to 150psi. We are slowly ramping up the pressure in the system. We are currently testing at 80ps... | g14566 | [
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<p>tl;dr: Hohmann Transfer appears to be the optimal way to achieve a circular-to-circular orbit, but is it possible to lower the periapsis in order to achieve a more elliptical orbit with apoapsis at the same distance, using less delta-v than a Hohmann transfer?</p>
<p>I've been playing an awesome game called Kerbal ... | g14567 | [
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<p><a href="http://web.physics.ucsb.edu/~mark/ms-qft-DRAFT.pdf#page=51" rel="nofollow">On page 51 Srednicki states</a>, "Note that the operators are in time order...we can insert $T$ without changing anything". This I agree with. But then on the next paragraph he states "The time order operator $T$, moves all...where t... | g14568 | [
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<p>I've always learned that a mixture of ice and water should reach equilibrium at approximately 0C. I've actually tried to create that a number of times in different contexts and always fail.</p>
<p>First, an ice bath in a plastic container. I get 3C, occasionally as low as 2C with a multimeter thermocouple. Grant... | g14569 | [
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<p>Looking for a way of calculating the maximum weight (W) to the rod with the given length (L) where the rod did not break and that only bend for (b) mm.</p>
<p><img src="http://i.stack.imgur.com/o5lps.jpg" alt="enter image description here"></p>
<p>Need only approximative solution (read: simple as possible :), noth... | g14570 | [
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<p>A <a href="https://en.wikipedia.org/wiki/Y-%CE%94_transform" rel="nofollow">$Y-\Delta$ transformation</a> can be applied to circuits in order to make an equivalent circuit (but simpler to put in terms of series/parallel devices). Wikipedia and other books show how to deduce the relation between resistances in a netw... | g14571 | [
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<p>I am undecided about the field I want to do my PhD in, in graduate school. I am asking because the applications that I am filling ask me to write the intended field of study. </p>
<p>I found the people who do theoretical high energy physics are the best one able to describe physics and explain it at all levels, oth... | g14572 | [
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<p>what growth conditions should the potential inside the Hamiltonian $ H=p^{2}+ V(x) $ has in order to get ALWAYS a discrete spectrum ??</p>
<p>for example how can we know for teh cases $ |x|^{a} $ , $ exp(b|x|) $ and so on with real parameters a,b and c </p>
<p>how can we prove that for theses potentials we will ... | g14573 | [
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<p>The motivation for my question is understanding how electricity gets through your skin as opposed to running along it, and how the presence of things like water on the skin affect the relative deadliness of electricity, or ability of it to permeate the skin. </p>
<p>I don't understand how to view the body as a resi... | g14574 | [
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<p>The paper I am trying to understand is here:
<a href="http://pra.aps.org/abstract/PRA/v49/i2/p1473_1" rel="nofollow">http://pra.aps.org/abstract/PRA/v49/i2/p1473_1</a></p>
<p>The paper describes the quantum teleportation protocol in a general case with continuous dynamical variables (position and momenta) in contra... | g14575 | [
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<p>While I've covered a basic course in Quantum Mechanics, I'm self-studying Landau & Lifshitz's book to help me understand what's going on.</p>
<p>Unfortunately, I'm stuck on the very first equation in the book.</p>
<p>Landau & Lifshitz write:</p>
<blockquote>
<p>The basis of the mathematical formalism of... | g14576 | [
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<p>How can I apply <strong>C.O.E</strong> to a system that applies magnetic & electric fields at the same time to do work, and convert energy from one form to another? </p>
<p>Let assume we have a conductor that moves within a magnetic field(electric motor) how can <strong>C.O.E</strong> be applied so that input $... | g14577 | [
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<p>Forgive me for the silly question, but I just don't get it.</p>
<p>I just completed an elementary course in mechanics, and I am curious to know what I am about to ask.</p>
<p>We have, all year, dealt with many forces like gravity, friction, normal forces, tensions etc. </p>
<p>But only one of them is listed as a ... | g14578 | [
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<p>What are the actual factors that play a role in the accretion of matter into galaxies? I read about Accretion Disks but I don't quite understand how they work yet. </p> | g14579 | [
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<p>How can you prove the uncertainty for position is:</p>
<p>$$\Delta{x} =\sqrt{\langle x^2\rangle-\langle x\rangle^2}$$</p>
<p>$\Delta{x}$, taken to be the root mean square of x.</p>
<p>$$\Delta{x} =\sqrt{\langle \left(x-\langle x\rangle\right)^2\rangle} $$</p>
<p>$$\Delta{x} =\sqrt{\langle \left(x-\langle x\rangl... | g14580 | [
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<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://physics.stackexchange.com/questions/4704/black-hole-analog-experiment">Black hole analog experiment?</a> </p>
</blockquote>
<p>I will explain my situation a little bit:</p>
<p>My teacher assign a experimental project that must be includin... | g448 | [
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<p>To my understanding, matter and energy are one and the same. Shifting from $E$ to $M$ in Einstein's famous equation requires only a large negative acceleration. If $M$ really is $E/c^2$, does that make matter the solid state of energy? I've read a lot about positron-electron collisions at high energies creating l... | g46 | [
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<p>Ordinary matter and antimatter have the same physical properties when it comes to, for example, spectroscopy. Hydrogen and antihydrogen atoms produce the same spectroscopy when excited, and adsorb the same frequencies. The charge does not make a difference in the potential (regardless if it's generated by a proton o... | g321 | [
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<p>say you had a large quantity of a heavy element such as uranium... AND you put a massive amount of energy into it, so that it began to undergo nuclear fission and transformed to a significantly smaller element(s). Would it be possible to use this energy to now begin a process of fusion, to output energy? And then on... | g14581 | [
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<p>I am interested in modeling water flow including boundary flow (with friction) against other objects in the path of the water flow.</p>
<p>I'm not a physicist but I am interested to learn the relevant physics (and the corresponding mathematical model) required to begin modeling a generic simulation engine. </p>
<p... | g14582 | [
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<p>Is it (the output, i.e, spherical, flat, hyperbolic) describing the physical shape of the universe and its curvature at any given instance of time <em>or</em> is it describing the shape of the expansion function applied to the universe? (i.e, the evolution of the universe spatially over time)</p>
<p>So a cone shape... | g14583 | [
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<p>In particle physics experiments, pileup occurs when two particles hit the same detector (say a calorimeter) at roughly the same time, resulting in what looks like a single event with higher energy than either one. Naturally, this can be a pain when analyzing data, and I've heard bits and pieces about methods for sub... | g14584 | [
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<p>It seems to me that the notion of an "S-matrix" refers to several different objects</p>
<p>One construction you can find in the literature is allowing the coupling constant to adiabatically approach 0 in the asymptotic past and future. This means the incoming and outgoing states belong to the free theory and the S-... | g14585 | [
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<p>In q. 22 in page 141, I am asked to show that if $U^{\alpha}\nabla_{\alpha} V^{\beta} = W^{\beta}$, then $U^{\alpha}\nabla_{\alpha}V_{\beta}=W_{\beta}$.</p>
<p>Here's what I have done:
$V_{\beta}=g_{\beta \gamma} V^{\gamma}$
so, $U^{\alpha} \nabla_{\alpha} (g_{\beta \gamma} V^{\gamma})=U^{\alpha}(\nabla_{\alpha} g_... | g14586 | [
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<p>I think I've come across a paradox while studying general relativity. Wikipedia states that the deflection angle of light by a point mass is $4GM/(c^2b)$.</p>
<p><a href="http://en.wikipedia.org/wiki/Gravitational_lensing_formalism" rel="nofollow">http://en.wikipedia.org/wiki/Gravitational_lensing_formalism</a></p... | g14587 | [
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<p>This is a student inquiry sparked by sheer curiosity.</p>
<p>Wikipedia states the <a href="http://en.wikipedia.org/wiki/Drag_%28physics%29" rel="nofollow">drag equation</a>, $F = 1/2v^2pC_dA_c$.</p>
<p>(p = mass density of fluid/gas, v = velocity, c_d = drag coefficient, a_c = cross sectional area perpendicular to... | g14588 | [
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<p>I was wondering about hydrostatic equilibrium (the balance of radially inward and outward forces) in large (i.e. above the Chandrasekhar limit) stars. It is often said that when the gravitational force exceeds any outward forces or pressures, mainly the electron degeneracy pressure I'm thinking, the star collapses i... | g14589 | [
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<p>I've been trying to get familiar with string field theory (SFT) and I've stumbled upon the statement that the Ramond-Ramond (RR) sector of Nathan's SFT has not been constructed yet. Why is that? </p> | g14590 | [
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<p>Examining cosmic ray neutron radiation near ground by neutron monitors for example (<a href="http://www.nmdb.eu" rel="nofollow">http://www.nmdb.eu</a>), different stations show similar dynamics in the signal.</p>
<p>At one station, I like to "substract" the incoming radiation in order to obtain information about lo... | g14591 | [
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<p>The question comes from Ryder's Quantum Field Theory, 2nd edition. The author was looking for relativistic spin operator. It was concluded that it cannot be $J^2:=\mathrm{J} \cdot \mathrm{J}$, where $J_i$ is the generator for rotation in Lorentz group.</p>
<p>p.56:</p>
<blockquote>
<p><em>$\ldots \Sigma$ is, of ... | g14592 | [
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<p>Actually I can't expand much as the question pretty much explains the query. I would be interested in the method of estimating an answer as well as a potential way to measure it experimentally. Thanks.</p>
<p>P.s. I'm not sure what tags to include for this one - for those that can, feel free to edit them as you see... | g14593 | [
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<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://physics.stackexchange.com/questions/7838/on-causality-and-the-big-bang-theory">on causality and The Big Bang Theory</a> </p>
</blockquote>
<p>Asking here in layman's terms..</p>
<p>When theoretical physicsists discuss the origin of our Univ... | g51 | [
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<p>I was reading about this asteroid (apparently, it has a moon, isn't that awesome?) and I started thinking about if I was on this asteroid, and I jumped, would I fall off?</p>
<p>It's been a while since I did something like this, so I went to Wikipedia to get some formulas. There I found</p>
<p>$$v_e = \sqrt{\frac{... | g14594 | [
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<p><a href="http://physics.stackexchange.com/q/2230/">This Phys.SE question</a> asks why and how the speed of light is constant. I would like to ask a related, almost converse question: <strong>Given that the speed of light is constant,</strong> how could I explain to a young-earth-creationist who is still a proponent... | g14595 | [
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<p>Doing a Google search i found a paper called <a href="http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TJ4-4M21SWY-4&_user=10&_coverDate=06%2F30%2F2007&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_searchStrId=1716211562&_rerunOr... | g14596 | [
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<p>I read on Wiki that <a href="http://en.wikipedia.org/wiki/Earnshaw%27s_theorem" rel="nofollow">Earnshaw's theorem</a> has been proven for extended conducting bodies.
If we consider the case of a positive charge at the centre of a symmetric metal cavity-
the positive charge and the induced negative charge constitute ... | g14597 | [
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<p>Context: The recent paper <em>The quantum state cannot be interpreted statistically</em> by Pusey, Barrett and Rudolph (now On the reality of the quantum state, <a href="http://dx.doi.org/10.1038/nphys2309"><em>Nature Physics</em> <strong>8</strong>, 475–478 (2012)</a>, <a href="http://arxiv.org/abs/1111.3328">arXiv... | g14598 | [
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<p>How is the violation of the usual CHSH inequality by a quantum state related to the entanglement of that quantum state?</p>
<p>Say we know that exist Hermitian and unitary operators $A_{0}$, $A_{1}$, $B_{0}$ and $B_{1}$ such that
$$\mathrm{tr} ( \rho ( A_{0}\otimes B_{0} + A_{0} \otimes B_{1} + A_{1}\otimes B_{0} -... | g14599 | [
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0... |
<p>I'm just curious. I figure atoms fuse occasionally just by chance, like quantum tunneling or <a href="https://en.wikipedia.org/wiki/Rogue_wave">rogue waves</a>. Is this true? If so, any idea how often?</p> | g14600 | [
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<p>I am hoping to discuss some details of electronic structure calculations. I am not an expert on this topic, so please forgive any abuse of terminology. It is my understanding that first principles electronic structure calculations are based on perfect translational symmetry of a crystalline lattice. Further, that... | g14601 | [
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<p>Now we always talk about the so-called <a href="http://www.sciencedirect.com/science/article/pii/S0003491605002381" rel="nofollow">Kitaev spin liquid</a>. One important property of spin liquid is <strong>global spin rotation symmetry</strong>. Let $\Psi$ represents a spin ground state, if $\Psi$ has global spin rota... | g14602 | [
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<p>I have to simulate the electric field within a gas filled discharge gap generated by a radio frequency voltage generator. The circuit, provided to me by the experimenters somewhat far away, is given in the second picture below. </p>
<p>Now the program I use expects me to feed it the time depended voltage curve and ... | g14603 | [
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<p>I was considering the S-dual of the Type I' String theory (the solitonic Type I string theory).</p>
<p>That is the same as the S-dual of the T-Dual of Type I String theory. Then, that means both length scales and coupling constant are inverted. So, since inverting the length scale of the theory before inverting the... | g14604 | [
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<p>A Stirling engine evidently functions by heating and cooling air, thus making the piston move up and down. What if the heated side of the cylinder were shaped as a sort of cone with a gentle slope, cut off before a point forms (I guess it would look like a trapezoid from the direct side), so that the surface that mu... | g14605 | [
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<p>How fast does the water travel down river when the discharge gates of a large dam are opened? Can the discharge-wave travel downstream faster than the water? Is this likely to occur for a real river and an actual sudden discharge from a large reservoir?</p> | g14606 | [
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<p>As is usually said, measurement of an observable $q$ leads to collapse of wavefunction to an eigenstate of the corresponding operator $\hat q$. That is, now the wavefunction in $q$ representation is $\psi(q)=\delta(q-q_0)$ where $q_0$ is result of measurement.</p>
<p>Now, in reality measurements are never exact, so... | g14607 | [
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<p>In my curriculum, the <a href="http://en.wikipedia.org/wiki/Decay_constant" rel="nofollow">decay constant</a> is "the probability of decay per unit time"</p>
<p>To me, this seems non-sensical, as the decay constant can be greater than one, which would imply that a particle has a probability of decaying in a time sp... | g14608 | [
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<p>is it possible to either demonstrate the principle or make a SEM ( electron microscope ) at home or lab as an enthusiast??
and how can i start?</p> | g14609 | [
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<p>I hope this isn't a stupid question for you guys but here we go.
As you travel close to the speed of light, it is to my understanding you gain mass.. does this also apply when the brain sends electrical signals to the muscles? Do the signals (that are traveling at the speed of light) cause the body to weight more? P... | g14610 | [
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<p>I understand that in the limit that h_bar goes to zero, the Feynman path integral is dominated by the classical path, and then using the stationary phase approximation we can derive an approximation for the propagator which is a function of the classical trajectory (see <a href="http://www.blau.itp.unibe.ch/lectures... | g141 | [
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<p>As far as I know, quantum hall effect and quantum spin hall effect has chiral edge state. Chiral edge state is usually closely related with delocalization, since back scattering is forbidden. However, some topological nontrivial state does not have chiral state, such as majorana bound state in topological supercondu... | g14611 | [
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<p>I'm wondering if there are any good indicators on how even the heat is distributed on an object (for simplicity, a flat object maybe)? What are the possibly reasonable ways to maximize the evenness if varying the shape of the object is allowed. </p> | g14612 | [
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<p>I learned in my undergraduate physics class that atoms have magnetic fields produced by the orbit of electrons and the spin of electrons. I understand how an orbit can induce a magnetic field because a charge moving in a circle is the same as a loop of current. </p>
<p>What I do not understand is how a spinning bal... | g14613 | [
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<p>I'd like to know what are the differences in timbre - or the acoustic properties of a sound - that allow us to differentiate between a sound which is quiet (but close-by) and one which is far away.</p>
<p>For example, you can tell when someone near to you is playing an instrument quietly even without looking to see... | g14614 | [
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<p>I know that:<p>
$G=6.67300 × 10^{-11}\dfrac{Nm^2}{kg^2}$(Gravitational constant)<p>
$K_e=9×10^9\dfrac{Nm^2}{C^2}$(Electric constant or Coloumb's constant)<p>
$k_m=1×10^{-7}\dfrac{Ns^2}{C^2}$(Magnetic constant)<p></p>
<hr>
<p>But what are the meaning of this values? Would the universe be much different with a littl... | g14615 | [
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<p>I have a question about entangled state. Suppose I consider the entangled state $\frac{1}{\sqrt{2}}(|00\rangle + |11\rangle)$. I saw an argument for how measurement of the first bit is affected by whether or not the second bit is measured because this is an entangled state in an article I am reading. The argument is... | g14616 | [
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<p>In consistent histories, for gauge theories, can the projection operators used in the chains be not gauge invariant?</p>
<p>In quantum gravity, for a projection operator to be gauge invariant means it has to be diffeomorphism invariant. There are no localized diffeomorphism invariant operators, not even localized i... | g14617 | [
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<p>Here is the question from my textbook:</p>
<p>"In an insulated vessel, 250g of ice at $0^{\circ}$C is added to 600g of water at $18^{\circ}$C. What is the final temperature of the system?" </p>
<p>The solution says that it takes more heat to melt ice than to cool water, so some ice will remain. It says the final... | g14618 | [
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<p>This is based upon an question I had, since in Jupiter there is no oxygen a simple fire cannot be started let alone even happen due to its temperature. Anyway that being said, If I somehow used a space-shuttle to take a atomic weapon size of Tsar Bomba and successfully detonated the mass-destruction weapon would the... | g449 | [
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<p>I was reading <a href="http://www.messagetoeagle.com/speedoglightnotfixed.php">this article</a> recently, which summarizes a couple of new studies into the speed of light.</p>
<blockquote>
<p>In one paper, Marcel Urban from the University of Paris-Sud, located in Orsay, France and his colleagues identified a quan... | g14619 | [
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<p>Assuming one were in a capsule of some kind, with no window or instruments, and you swung into the gravitational field of a massive object (planet). Assuming no atmosphere to provide friction, could you tell you were curving...there wouldn't be like centrifugal force, would there? Would you even feel gravity until y... | g14620 | [
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<p>I am posting this question again because, Willie Wong asked me to do it. So it is a continuing post of the <a href="http://physics.stackexchange.com/questions/52590/interaction-potential-in-standard-phi4-theory/52642?noredirect=1#comment122497_52642">Interaction potential in standard ϕ4 theory</a>.</p>
<p>I have be... | g14621 | [
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<p>There are 51 stars within 17 light years of the Earth (<a href="http://en.wikipedia.org/wiki/List_of_nearest_stars">source</a>). If one of these stars was to become a supernova, how would they effect the Earth?</p>
<p>I have read the Wikipedia article <em><a href="http://en.wikipedia.org/wiki/Near-Earth_supernova">... | g14622 | [
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<p>I know the relationship between normal and correlated two-particle Green Functions for fermions:
$$G_c(1,2,3,4)=\Gamma(1,2,3,4)=G(1,2,3,4)+G(1,3)G(2,4)-G(1,4)G(2,3)$$
Also known as irreducible n-particle Green function or n-particle vertex (there are many definitions so I'm confused).</p>
<p>Definitions for G also ... | g14623 | [
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<p>I just watched <a href="http://www.youtube.com/watch?v=MP3jAg1C_hA" rel="nofollow">this SpaceRip video on YouTube</a> which shows pictures taken by Hubble while looking into the disk of the Andromeda galaxy to study a certain type of variable star. It occurred to me that if we can study individual stars in Andromeda... | g14624 | [
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<p>Physics is a hobby interest of mine, so I may be asking a senseless question, but there is something I cannot get my head around when it comes to relative frames, the <strong>constant</strong> speed of light (as a top-limit for any speed) and the following situation:</p>
<p>Imagine two spaceships, capable of reachi... | g14625 | [
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<p>Considering that there's a lot of debris in space and that impacts fling out rocks into space all the time, why do we only have one large natural satellite - the Moon? Shouldn't there be all kinds of rocks in all shapes and sizes orbiting the Earth?</p> | g14626 | [
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<p>I can't think of any better title. Here is the content that I got question
<a href="http://cnx.org/content/m10247/2.31/" rel="nofollow">http://cnx.org/content/m10247/2.31/</a></p>
<p>As it state the nature of DTFT's spectrum is periodic as it show in figure 1
<img src="http://i.stack.imgur.com/RHr9S.png" alt="enter... | g14627 | [
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<p>Where can I find pictures of the shadow of any of the <a href="http://en.wikipedia.org/wiki/Moons_of_Jupiter" rel="nofollow">Jovian moons</a> partially covering the <a href="http://en.wikipedia.org/wiki/Atmosphere_of_Jupiter#Great_Red_Spot" rel="nofollow">Great Red Spot</a>?</p>
<p>A series of such pictures over ti... | g14628 | [
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0.05752108618617058,
0.008003... |
<p>Jupiter has many <a href="http://en.wikipedia.org/wiki/Jupiter_Trojan">Trojan asteroids</a> located at Lagrangian points L4 and L5 and <a href="http://en.wikipedia.org/wiki/Hilda_family">Hilda asteroids</a> dispersed between points L3, L4, and L5.</p>
<p>Does the Earth have similar satellites? If so, how many?</p> | g14629 | [
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<p>This question is if the von Neumann–Wigner interpretation, aka "consciousness cause collapse" (see e.g. John von Neumann's 1932 book The Mathematical Foundations of Quantum Mechanics) is compatible with the quantum Zeno effect (see Sudarshan, E. C. G.; Misra, B. (1977) "The Zeno's paradox in quantum theory", Journa... | g14630 | [
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<p>So I've read a question on here about <a href="http://physics.stackexchange.com/questions/88824/capillary-action-in-a-slanted-tube">Capillary action in a slanted tube</a>, but my question goes a little further. Firstly though, could someone explain to me what is meant by the only answer to that question. The answer ... | g14631 | [
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<p>Two distinguishable gases are in separate volumes $xV$ and $(1-x)V$ $(x\in [0,1])$ respectively, and the number of particles on each side is $xN$ and $(1-x)N$ respectively. The volumes are separated by some tap or something at first. If we then open the tap, the gases will mix, the ideal mixing entropy is given by
$... | g14632 | [
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0.02021409384906292,
0.021000506356358528,... |
<p>Can anyone please explain me on this matter along with day to day examples?</p> | g14633 | [
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0.005408911034464836,
... |
<p>Consider the following parallel plate capacitor made of two plates with equal area $A$ and equal surface charge density $\sigma$:</p>
<p><img src="http://i.stack.imgur.com/E3Mkn.png" alt="enter image description here"></p>
<p>The electric field due to the positive plate is </p>
<p>$$\frac{\sigma}{\epsilon_0}$$</p... | g14634 | [
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<p>Suppose we have the following experimental values for $\eta' \rightarrow \eta \pi \pi$ decay width:</p>
<p>$\Gamma_{\eta' \rightarrow \eta \pi^+ \pi^-} = 0.086 \pm 0.004$</p>
<p>$\Gamma_{\eta' \rightarrow \eta \pi^0 \pi^0} = 0.0430 \pm 0.0022$</p>
<p>We are investigating this decay in the isospin invariant limit ... | g14635 | [
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<p>In Landau's Fluid Mechanics p. 8 (2nd edition) he writes for the thermal expansion coefficient $\beta = (1/V) (\partial V/\partial T)_P$:</p>
<blockquote>
<p>For a column of gas in equilibrium which can be taken as a thermodynamically
perfect gas, $\beta T = 1$ [...]</p>
</blockquote>
<p>This is not not obviou... | g14636 | [
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