Creation Definition and 310 Threads

Hi, I wonder what people think of the following mechanism for matter creation in an expanding Universe. Imagine a particle-antiparticle pair coming into existence from the vacuum. As I understand it, they will annihilate each other in the time that a light signal takes to travel from one...

While researching dark matter and dark energy, I came across the following passage on NASA's website: "The first property that Einstein discovered is that it is possible for more space to come into existence. Then one version of Einstein's gravity theory, the version that contains a...

Suppose a K.G. field. When I apply the creation operator on the vacuum, how do I know it is a pion or any other boson?

Homework Statement two photons collide head-on and create an electron and an anti electron. The energy of photon 1 is given, but not for photon 2. Find the velocity β of the systems rest frame (where the total momentum is zero.) Homework Equations β=v/c γ=1/√1-β^2) β=pc/E The...

There is this paper that someone posted in a thread: http://arxiv.org/abs/0904.2287 Called "QFT as pilot-wave theory of particle creation and destruction" Which talks mainly about Bohmian interpretations applied to QFT (the whole paper is in QFT scheme). However, in chapter 3, it talks...

Hi, I have a whole bunch of data (Arrays of the form H1, H2, H3 etc) that I want to crunch to create 10 more variables. I did: For[i=1,i<23,i++,{f1(i),f2(i),..,f10(i)}>>>"temp.mx"] Where fj(i)= fj(H1[[i]],H2[[i]],...), the functions are different functions of the numerical data I...

Hi, I'm doing some exercise about second quantization. In a exercise about spiorial field I have to explicitly write the Hamiltonian of a Majorana-Langrangian, in terms of operators of creation and annihilation: A_{\vec{k},\lambda} that acts on Fock's space. The point is that during the...

Homework Statement Show that f(a†a)a† = a†f(a†a + 1) Where f is any analytic function and a and a† satisfy commutation relation [a, a†] = 1. The Attempt at a Solution I have used [a, a†] = aa†-a†a=1 to write the expression like f(a†a)a†= a†f(aa†) but I don't know what to do...

Sorry to ask all of you but i have i wild idea about the creation of the universe and I’m not shore where to send it... can you please give me an idea? I'm not actual a physicist but the idea sounds pretty good. Thanks

I did this problem on this British Physics Olympiad paper and it assumed that when a star bigger than the sun collapses under its own gravity to create a neuron star the magnetic flux stays constant. Please explain Thanks

"creation of space" what exactly does this mean dear all, I must admit, the wording "space is created" sounds to me rather unscientific (forgive me for being provocative). I know that, in general relativity, there are (more or less arbitrary) reference frames and distances within these...

I'm currently working on a sci-fi story, which largely revolves around a single world (which the current name for is Thea, you'll see why when I describe it...). Okay, I understand I've got some hard questions, so I've cut them into 5 labeled sections. Any help is vastly appreciated! :)...

Labor Day and the Creation of “Free,” Anti-Feudalistic Labor Through Regulation Interesting blogpost on the unfree state of free labor in the early industrial period Edit by mod: We don't allow personal blogs as sources more here I'm still deciding on this student paper...

Hello! Im trying to do QFT on my own and its going fine.. except one confusion now. We have our operator fields corresponding to our observables, and our state which is a function of space and time. But doing the second quantization we get the creation and destruction operators which now...

Air weighs about 800 times less than water, 1 litre of water weighs 1000 gms approx. while 1 litre of air weighs 1.25 gms approx. So theoretically it should need less energy ( in fact a lot less) to create a rough vacuum in a given volume than it would need to remove a liquid (water) from the...

Hello, I have an Idea that i would like you guys to examine and tell me if it is good or not. Since people do not yet fully understand a black hole, and supposedly predicted my Hawking that a black hole can disappear out of nothing and that the information can't be lost, or just vanish into...

I have ideas about people I personally would like to put on these islands. :devil: My fear would be that these people will eventually leave these "islands" and come back to the real world unable to adapt or even understand how society operates. No laws and plenty of guns. Isn't this what we...

in a double slit experiment, if we find which-way and then stop observing the photon and send it again through another double slit (kept in, say, series), would an interference pattern occur?...the second time around

Hello! I'm assuming the model of the Big Bang Theory and I'm asking specifically about the 'moment' of creation; I'm in no way well-versed in this; so please be gentle : * Are the laws of physics applicable to the beginning on the universe? * The Law of Conservation will not apply for this...

I am trying to find out, with little success, at what point in time did gravity become into existence? or at least a theory that is consistent.

With an unemployment rate above 9% a $14.3Trillion national debt (with proposed cuts of $2Trillion) expected to grow another $7+Trillion, spending at approximately 25% of GDP, roughly 43% of all spending is on credit, and GDP growing at less than 2% - something must be done to encourage economic...

In the free case,we decomposite the free Hamiltonian into the creation and annihilation operators, i just wonder why this ad hoc method can not be used to the interaction theory?

in diode why there is creation of depletion region? advanced thanks.

Hi, I'm hopng someone can help me. I've begun working my way through Lahiri's "A first book of quantum field theory". In chapter 3 he shows the Fourier decomposition of the free field is given by \phi(x) = \int \frac{d^3 P}{\sqrt{(2\pi)^3 2E_p}} (a(p) e^{-ip\cdot x} + a^D(p) e^{ip...

If a burglar busts into your home and sees a safe, what's the first thing he is going to do? Bust it? No, he is going to take it home and then bust it. Having a safe is like doing the burglar a favor, basically telling him that "hey I've organized and gathered all my valuables in this box...

Hi, I've studied a bit nuclear physics, and I don't get how the mathematics under the creation and destruction of particles is handled. if shrodingher equation leads a state vector in the usual way Hpsi=ih d(psi)/dt let's suppose I've N particles and psi=psi(q1...qn) so, if a new particle...

During the creation of the universe, aka the big bang, it is recognised that matter was in a greater supply then anti-matter. The reason for this is unknown. So we are able to create anti-matter at great expense, have we ever tried to make anti-matter into matter? Because if the method...

Hi physicsforum members, I am currently in a discussion with a fellow traveler on the chances of a Big Crunch. To my knowledge, it's a long shot. But to him it is the accepted mainstream view on the "ends" of the universe. Before I get to my question, I have to provide some back story (I...

take a cunductive wire. coil it (for conventional space) then run electrons through it with 8.98755179 × 10^16 J (the same number for the speed of light squared) of energy. ( i realize that doing that is nearly or completely impossible). using the equation m=e/c^2 e and c^2 are the same...

I've looked through all my course notes, but I just don't even know where to start with this problem. The problem: \langle 1 \mid x^2 \mid 2 \rangle Use the annihilation and creation form for x to obtain the above matrix element. What I do know: I know that x = \sqrt{\hbar /...

I am making a wind tunnel to test the lift of an airfoil when chaning the variables of angle of attack and air velocity. For a good EEI I need more then 3 speeds. However, all the people I know only have 3 speed fans, I don't know how to get more speeds as the wind tunnel gets built around the...

Hi, I am proposing a simple way to create a magnet with single pole. Not being a physics/science graduate, this came out of interest of thinking only. Lets consider a sphere, which is hollow inside and has a thickness to it at the surface only. If i cut a certain segment and make it out of...

Hello everyone, :smile: I was working to create a program to list the sequence: 1 12 123 1234 12345 ... The user will decides how many terms of sequence are displayed. For example the terms, n, given above are five. Will you help me please? I think I need to use the FOR loop here...

Homework Statement Evaluate <n|p^2|n> where p is the momentum operator for the quantised harmonic oscillator. Homework Equations creation operator: a+|n>=sqrt(n+1)|n+1> annihilation operator: a|n>=sqrt(n)|n-1> The Attempt at a Solution the operator p can be defined in terms of...

When massless particles are given mass by the Higgs mechanism, then there is no problem with charge conservation if a matter-antimatter pair is created. But what happens when a single charged particle is created? Where happens to the conservation of charge?

Homework Statement A spark occurs at the tip of a metal needle if the electric field strength exceeds 3.0x10^6 N/C. What is the minimum surface charge density for producing a spark? Homework Equations int(EdA) = (Qin) / e0 The Attempt at a Solution I imagine the surface as a cylinder with...

Say we have a maglev train traveling i a vacuum. The only thing limiting its speed is the g-force tolerance of the passengers. The train would therefore accelerate at a certain rate until halfway, and then decelerate until it reached its destination. What would be the traveling time of...

This question came to me during my reading of "A Brief History of Time" and learning of Mr. Hawking's statement of the universe arising spontaneously from chaos as a result of the law of gravity, which would preclude a God's role in creation. ABHT states that "one could still imagine that God...

Hi all, Doing a project for 1st year special topics physics module in university and we're thinking of doing the project on stars. Just wondering if anyone might know of any good literature on the sublject that we could look into as part of our research. We have until mid January to do the...

1. Explain why <n|(a-a+)^3|n> must be zero 2. a and a+ (a dagger) are the raising and lowering operators (creation and annihilation operators). 3. Because it says explain, I am not sure any mathematical proof is needed. I am best answer is that because (ignoring that the bracket...

Sorry if this question is too elementary (no pun intended) for this forum. If stellar fusion of iron takes more energy than it produces, how are heaver elements formed? Cheers, JP

If a typical star is created by a spinning ball of gas, how does the gas start spinning in the first place to fuel that birth?

Can strings be created and destroyed (like particles)?

Hey, everyone. This is my first post. I am a physics and science lover with little university level schooling in those fields. I was reading the new hawking/mlodinow book "The grand design",a nd had a question about the spontaneous creation on the quantum level. The book states that...

Homework Statement Potassium benzoate C6H5CO2K can be prepared from benzyl alcohol, C6H5CH2OH, and potassium permanganate KMnO4 in aqueous KOH. The manganese is converted to MnO2 The Attempt at a Solution So, my attempt to balance has left me scratching my head C6H5CH2OH + KMnO4...

Hi. If c and c^\dagger are fermion annihilation and creation operators, respectively, we know that cc^\dagger+c^\dagger c=1 and cc=0 and c^\dagger c^\dagger=0. I can use this to show the following [c^\dagger c,c]=c^\dagger cc-c c^\dagger c=-cc^\dagger c=-c(1-cc^\dagger)=-c But on the...

How was matter created in this universe? If the Higgs Boson is theoretically able to create matter from energy, then isn't that fairly good proof that it exists? Or are there other explanations? cheers, BT

Okay, I've heard that in Stephen Hawking's new book, The Grand Design, he claims that the law gravity somehow created the universe from nothing. Can any of you give me a conceptual understanding of how this could occur?

This has puzzled me for a very long time. I know the theory that the universe was created from a big bang, but this means that all the matter in the universe existed in a different form before that. Be it gas or some other weird substance, it still existed. So how can all this substance appear...

Can we turn the energy of a G field into mass ?