Virtual Definition and 577 Threads

So virtual particles are allowed to exist so long as they 'give back' their energy in the time alloted by the uncertainty principle. This might be a fairly naive question, but it occurred to me that maybe the opposite is true. Can 'real' particles cease to exist for brief flashes of time without...

Im new and not that advanced in science so can you try to keep your answers simple. My question is can virtual particles break the law that energy cannot be created or destroyed? Have virtual particles been proven/observed? thanks in advance for your answers

Homework Statement anyone guide me step by step how to use virtual work method to calculate all reactions on this beam? thanks Homework Equations The Attempt at a Solution

Hahaha, yeah I did a search on these forums for questions regarding Virtual Particles and it seems its "the horse that's been beaten to death with a stick". But, I still have questions so please try and answer them because the people on there are much more versed than me in physics. I am a...

1) In non-mathmatical terms, please correct my description of vitual particles... a) virtual particles are real but too small to be observed directly. i.e. their dimensions are within Plank's values and subject to Heisenberg's uncertainty principles. b) virtual particles are real...

More...

Is there a way to calculate the wavelength, frequency or energy (per photon) of the virtual photons that charges exchange to account for the Coulomb force? This is assuming that it's always the same wavelength, of course.

If there is a 1024x1024 array of 32 bits numbers and we need to normalize by columns. Algorithm goes through each column, finds max and divide all numbers by the max. It would be certainly wise to store the pages by column? My rationale: 1M (2^20) main memory is allocated and each...

Homework Statement The virtual image produced by a convex mirror is one-quarter the size of the object. b) What is the focal length of this mirror? Homework Equations 1/di = 1/f - 1/do The Attempt at a Solution i found di to be -9.3 cm but when i solved for f i keep getting it...

using the principal of virtual work, find the reactions of the following structure as far as i know, to solve using virtual work i take the statically determinate structure and release one of the support reactions making it indeterminate (1st degree), after picking my brain with the...

I have two questions: 1. Wikipedia defines the will to live as "a psychological force to fight for survival, particularly when one's life is threatened by an injury or disease such as cancer." Have there been any experiments or studies done showing that a conscious decision by an individual...

A few years back, you couldn’t open any newspaper, magazine or law review journal without seeing yet another article about the crazy things that were going on in virtual worlds. *Today, not so much. *News of the*closure of Metaplace didn’t even make it very far beyond the usual VW blogs… *So...

An interesting idea came up in my class last week about the future transportability of virtual world avatars into other virtual worlds. *For years this has been one of the elements of a utopian virtual future, where all avatars have property and free speech rights and they can all move back and...

I am watching this now and it looks pretty interesting. One thing that caught my attention was a segment about a Japanese school that teaches internet etiquette to young children. http://www.pbs.org/wgbh/pages/frontline/digitalnation/etc/synopsis.html Watch online...

Hi Got a question, hoping someone can give a good explanation for. We all know that large static uniform electric fields have the potential to ionize. (Dielectric breakdown of Air - Static Electricity Shock). In the Quantum picture, why does this occur. Take for instance the photo...

derive Coulombs law of electrostatic force by using virtual photon exchange theory of electrostatic field

So, all I ever keep reading is that virtual particles don't HAVE to satisfy E2 = p2 + m2. Should it instead be that they don't satisfy the energy relation. Also, can someone show the general case mathematically how the energy relation is violated. If it's easier maybe a simple example of an...

i've been scrolling through the archives and can't get an answer if virtual particle exist or not or are real,I get different answers looking on websites.

Hi, I'm trying to get my story straight about virtual photons. So far, my understanding of them is that they are the particles that mediate the electromagnetic interaction, and they only exist a short time due to the Heisenberg uncertainty principle meaning that they can't be directly observed...

I'm not making any statements here, only asking questions. When I take two permanent magnets and I feel the repulsive force between them, Feynman QED says it is the momentum of the virtual photons "pushing" the magnets apart? Experiments have been done, forcing some of these virtual...

Im having such a hard time understanding what these types of images even are this is what I've read so far real images "rays from a point of the object meet at a point" im so confused? what? they meet at the principal focus when reflected?? can somone please dumb this down for me in the...

Recently, I asked my physics teacher how to measure the height of a virtual image behind a concave mirror. He said he wasn't exactly sure so he offered to give extra credit to anyone who could find information on how to do it. Is there anyone who can help?

Hi folks, I have a question about virtual particles, and so far I haven't been able to find an answer. Do virtual particles ever annihilate with real particles? (Black hole evaporation aside) For example, let's say we have a (real) electron, floating in space, and a virtual...

Can electrons, or other real particles for that matter, interact with virtual particles? Do virtual particles ever come into existence in between the electron's energy levels of an atom? Is there actually a vacuum between electron energy levels of an atom or is this an abstract...

Lisa, my virtual Christmas gift for you. I hope you don't have arachnophobia.

Virtual Machines: Do you have one ? Xen,VMware, Virtual Box Hi ... all ...Do you have a virtual machine ? (XEN, VMware, VirtualBox, or any other ...) ... please give more info on how you are using it ? I''m trying to find out what are the different ways to use them ?... how are people...

Hello, I am having hard time giving a geometric interpretation for the virtual velocity in classical mechanics, defined as: \delta \dot{x} = \frac{d}{dt} \delta x where \delta is the virtual differential operator, and \delta \dot{x} denotes the virtual velocity of x. I think having a...

I don't really understand quantum physics, but I would really like to know because I'm going to study it next year. Can someone explain it to me in laymens terms, thanks.

What is the principle of virtual ground? Please elaborate. Attempt: The input impedance of an op-amp is so high that virtually all input current is shunted to the feedback resistor when is works as interver. When noninverting input is grounded and internal resistance of op-amp is very high...

I wasn't sure whether this question should go in advanced or introductory physics but I decided to post here since it doesn't involve any complex maths. Homework Statement Part 1 Consider a neutral pion at rest. On the basis of conservation of energy and momentum alone, show that it is...

Virtual particles I'm confused. I have a degree in philosophy and physics is not my area of expertise. I have read about the subject so please don't give an answer fit for a 4th grader. What are virtual particles? Are they real or not? Are they some strange hybrid of reality and non-reality...

In introducing the concept of 'virtual photon',Halzen Martin writes (ch#1,P#7) "An ekectron emits a photon (the quantum of electromagnetic field) and as a result,recoils in order to conserve momentum.it is clearly impossible to conserve energy as well,so the emitted photon is definitely not a...

Why cannot virtual particles in the vacuum be directly detected? Experiments have shown the Casimir Effect that supports the idea of virtual particles does exist. But can we also detect the presence of virtual particles directly in the vacuum? The most common virtual particle to form is photon...

This probably belongs in the General discussion area but I'd really like to discuss the computer science aspect of this. The AI in this program seems quite amazing. I'm not sure what type of learning this AI has, would it be adaptive or preemptive... This seems like the pinnacle of modern day...

Do virtual particles disprove the law of conservation of energy? Are they really created out of thin air or does something cause them?

Please have pity on a poor ignorant layperson struggling for understanding... and keep in mind that I am mathematically impotent. I am trying to wrap my mind around the concept of expanding space-time with regard to quantum foam. Could someone please explain whether the "density" of quantum...

Just a casual thought I had, with no answer since I'm not well-versed in QFT: Given two point charges, the force between them is given by Coulomb's law, \frac{1}{r^2}. I know this is only fully accurate when the particles are stationary. What I'm wondering, is that since the force is mediated...

Homework Statement Derive the equation used for calculating the deflection of a beam at some arbitrary point. Because I haven't seen anything like this on the web or in textbooks, I am asking for some feedback. Homework Equations v_{k} = \int\frac{\delta M(x)M(x)}{EI} dx The Attempt...

How "Real" Are Virtual Particles? Are they a help to particle interaction or are they physically real? How come they are not observable to us? what i want to find out is if they are an artefact or not.I also know that there is a lot of debate to whether virtual particles exist in reality or not.

What is "virtual energy level"? What is "virtual energy level"?

I have a question about lenses and mirrors and the above topic.. As I understand it, a real image is one that formed when all the light from one source is converged again at another point and our eyes see that light again spreading from the converged spot. So if you put a screen at the spot...

Hey all, I am an undergraduate taking a particle physics class and we just learned that the EM force was caused by charges "spitting" virtual photons back a forth. In like second grade we learned that the EM force was dependent on the two charges involved (keeping this simple) and the distance...

Homework Statement An object whose height is 0.375 cm is at a distance of 10.5 cm from a spherical concave mirror. Its image is real and has a height of 1.145 cm. Calculate the radius of curvature of the mirror. Correct, computer gets: 1.58e+01 cm ACTUAL QUESTION How far from the...

Hey guys, does anyone have a strong link for a Virtual Chem Lab for General Chemistry labs? It can be online or downloadable. Thanks

Hello, I've lurked anonymously for quite a bit on these forums, and until now had no reason to register and ask a question. Background: high school senior with (otherwise) high GPA(3.9) and fairly good ACT score (31) seeking advice and consulting from experienced PF member. Now that...

How exactly do virtual particles add to energy mass while still complying with the conservation of energy? For instance, sea quarks, (virtual quark, antiquark pairs) are suppose to contribute to the mass of a brayon. Do they exist for a fleeting moment below the Heisenberg limit by popping in...

I thought this internet application created by http://lindenlab.com/" was interesting: http://en.wikipedia.org/wiki/Second_life http://secondlife.com/ It takes the idea of a video game to an extreme. Video games normally either capture some specific portion of real life (i.e. life...

Based on theories of an accelerating universe, how can the creation and annihilation of pairs of particles/anti-particles (virtual particles) generate energy in a vacuum (space) thus contribute to Eintstein's theory of a cosmological constant (positive pressure). And if the quantum...

Have any of you ever tried virtual office hours? For example, using a forum or chat session instead of sitting around your office for an hour twiddling your thumbs waiting for nobody to show up? I'm asking because I'm trying it right now for one of my courses. I could not find an hour...

On the wikipedia page about virtual particles it says: "If a single particle is detected, then the consequences of its existence are prolonged to such a degree that it cannot be virtual." Could someone explain to me why this is true, ie why is it that if we detect a particle it cannot be...