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0answers
39 views

Is there a typology of different fundamental physical objects?

As I understand it (and of course, I may be wrong!).... In classical mechanics, all objects are basically the same in the sense that They are composed of atoms bunched together. These atoms occupy ...
-3
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0answers
22 views

What is the best materiels for fixed target experiments with a linear particle accelerator? [on hold]

I need the best materiel for fixed target experiments using linear particle accelerators when accelerating electrons. By "best" I mean one that when the accelerated electron beam collides with it the ...
0
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3answers
258 views

Center Of Mass Troubles

I understand the concept of Center Of Mass(com), but I am having a difficult time interpreting the equation of the simplified case of one-dimension. The book I am reading defines the position of the ...
4
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1answer
55 views

Rejecting background in $B$-meson decay

I want to reconstruct the $B$ mass from the decay $$ B^0 \rightarrow K^{0*} \gamma \quad\text{ where }\quad K^{0*} \rightarrow K^{+} \pi^{-} $$ and the equivalent antiparticle decay. A key element in ...
2
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1answer
211 views

Classical models with unbounded particle number

Is there any classical model which deals with the birth, life and death of particles? What application could it have? I am talking about a 'billiard-ball' kind of model, but the kind in which balls ...
0
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1answer
48 views

two mutually attracted particles in 1D space

I'm wondering - can two particles under attractive force ever come to full stop in 1D space? Or will they oscillate for an infinitely long time?
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2answers
60 views

Has energy in 'transit' been incorporated into missing matter calcs.?

Has energy in 'transit' been incorporated into missing matter calcs. ?It would seem that, although very small in mass, the sheer number of particles shhoting about from one end of the universe to the ...
2
votes
2answers
213 views

The concept of particle in QFT

I never learnt QFT and I apologize for my (probably) elementary question. Somebody told me that in QFT a particle is viewed as an irregularity in the field. On the other hand, in an article in ...
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0answers
35 views

What does the phrase 'muons are brought to rest' mean?

I have a physics question in a text sheet. I am currently doing work on relativity where calculations of rest frames and laboratory frames are being completed. The formula: $t(\text{laboratory frame}) ...
2
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3answers
144 views

Is simulating the entire universe possible?

Is it concievable that we may one day simulate the entire universe with every single particle, field and law of physics factored in? Can n number of particles (say the number of particles that make up ...
0
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1answer
44 views

Special Relativity - three body problem

I have a problem with solving three-body problem in special relativity. I know that in general this problem doesn't have good solution, but I have a specific case when it should be good answer. ...
1
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1answer
39 views

In Bohmian mechanics, how does the particle's position affect where a particle is detected?

In Bohmian mechanics / pilot wave theory / de Broglie–Bohm theory, my understanding is that a particle's trajectory evolves based on its wave function, and that the position that particle is detected ...
1
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2answers
103 views

How do particles interact in Bohmian mechanics / pilot wave theory / de Broglie–Bohm theory?

I've read that in the de Broglie–Bohm interpretation of QM, the particle directed by its wavefunction has a trajectory (meaning both position and velocity) and that these are the only properties ...
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2answers
2k views

What is a wave? What is a particle?

I am reading a David Bohm book on quantum theory. He says the idea that light is both a particle and a wave is incompatible: (1) we know light has particle-like properties through the photoelectric ...
13
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3answers
472 views

Wave/particle-duality as result of taking different limits of a QFT

There is an account on dualities in quantum field theories and string theories by Polchinski from last week http://arxiv.org/abs/1412.5704 At the end of page 4, he writes the wave/particle ...
1
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1answer
147 views

What happens when an atom absorb electron/photon?

I'll give you a scenario or two, and please tell me what will happen and that shall answer my question. Thanks in advance. Scenario 1: Will an atom absorb an electron with kinetic energy greater ...
1
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0answers
18 views

How to calculate D0->K+K- decay with QCD factorization?

I am studying the decay of D0->K+K- and I calculated the result of Branching Ratio by Naive QCD and I wrote all the equations for amplitude and branching Ration and Hamiltonian and... for this decay ...
1
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3answers
160 views

Why is every particle a sphere?

I was wondering why is everything in this universe, I mean atoms and well quarks and photons and what not some form of sphere. Is there any exploitation to the sphere being perfect and only thing for ...
0
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0answers
8 views

how to completely remove the charge from the glass bubble particles?

Do you have any idea on how to completely remove the charge from the glass bubble particles (25-32 micrometer diameter)? Thanks
1
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1answer
56 views

using a given wavefunction to find particle properties

Let's say we have a given wavefunction and we want to find a particle that will fulfill the properties for that wavefunction. How can we do that? Is it possible? I was thinking of using Schrodinger's ...
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2answers
745 views

What really is the smallest “mass” or “object” in the universe?

Look at this here. With respect to the sciences, the atom is obviously not the smallest piece of mass. Apparently, if people have already broken down the atom in to particles smaller than so, why ...
1
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1answer
24 views

How to induce charge in glass bubble particles ?

I am trying to induce charge ( + or - ) in the glass bubble particles ( manufacturer 3M 25-32 micrometer) . Can anyone tell me how to effectively charge them. I have tried placing these particles in a ...
0
votes
1answer
72 views

Can matter be annihilated to form kinetic energy

I don't know much about conversion of energy and all, but I had a simple question: Can the energy released by converting matter into energy be used to set other particles in motion (increase their ...
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0answers
12 views

Particle Velocity and Air Velocity

Is the any relationship (equation) between particle velocity and air velocity? Is it possible to determine the air velocity from particle velocity?
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3answers
72 views

How are the half life of particles mathematically related to the inverse square laws?

This video https://www.youtube.com/watch?v=K6i-qE8AigE&list=PL3B0924C6A0CB8B67 explains how forces are boson particles. It talks about the other non-force particles giving off and creating bosons, ...
0
votes
1answer
58 views

How to convert cc to bar?

In astronomy/astrophysics, medium density is often given in cc, particles per cubic centimeter. Also, the temperature of the medium is usually given, in Kelvins. For some materials the melting point ...
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3answers
566 views

New subatomic particles

In reference to the findings talked about here http://online.wsj.com/articles/two-new-subatomic-particles-found-using-large-hadron-collider-scientists-say-1416409980 and other similar articles ...
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2answers
3k views

Why is lightning considered a plasma?

I was wondering why a lightning bolt is coined as "plasma", or a "spark" from an electrical wire/device is as well, yet flares, molten lava, and burning buildings are not(flares are pyrotechnic, ...
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3answers
228 views

Photons as fundamental particles

Is there any theory, current or debunked, that considers the photon to be a non elementary particle? That is to say, is the photon just the photon or is there possibly more to the photon than just ...
3
votes
2answers
101 views

What makes a one particle state?

I'm trying to understand free particle states in quantum field theory but I'm having trouble with one thing: what exactly defines a one particle state? For example, we can define a 'plane wave' as a ...
3
votes
2answers
56 views

Adding a tracer to the surface of a water droplet

I have a 2 mm water droplet generated by a syringe and falling down. I am using two perpendicular cameras to capture simultaneous frames from it. I need to track the droplet during the time and ...
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0answers
25 views

Where does the polarity of particles come from? [duplicate]

Going though current lessons, I can clearly see that some particles, electrons, are charged negatively and other, protons, are charged positively. Where does this polarity come from? Knowing that ...
5
votes
1answer
180 views

Is the particle reaction $π^- + p \to K^- + Σ^+$ possible?

I'm currently going over some undergraduate exams on particle physics and I'm having problems with a specific reaction, namely $$ \pi^- + p \to K^- + \Sigma^+ $$ which, in my opinion, is not allowed ...
3
votes
1answer
74 views

Non-deterministic particle system

This question is in the spirit of Norton's dome, an example of an apparently non-deterministic system in Newtonian mechanics. Under certain restrictions, the Picard–Lindelöf theorem guarantees the ...
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4answers
3k views

Which is more fundamental, Fields or Particles?

I hope that I am using appropriate terminology. My confusion about quantum theory (beyond my obvious unfamiliarity with its terminology) is basically twofold: I lack an adequate understanding of ...
0
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1answer
29 views

Help Understanding Gaussian Particle Distribution

I have a simple enough problem. I want to mathematically describe a Gaussian particle distribution of $N$ total particles with a spot size of 0.1 (sigma). I need a function that will tell me the ...
25
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4answers
7k views

What would happen if an accelerated particle collided with a person?

What would happen if an accelerated particle (like they create in the LHC) hit a person standing in its path? Would the person die? Would the particle rip a hole? Would the particle leave such a tiny ...
2
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1answer
157 views

Group Theoretic definition of a particle

We intuitively have a sense of what a particle means in the conventional sense. But is it possible to have a group theoretical definition of a particle, I mean in terms of irreducible representations ...
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3answers
258 views

Why is fundamental physics taught in terms of particles?

According to this paper, there can be no relativistic quantum theory of localizeable particles ("relativity plus quantum mechanics exclusively requires a field ontology"). Sean Caroll has also argued ...
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1answer
71 views

What is density? [closed]

Ok based on a mathematical stand point i get density im talking about a density in objects?how can one object with the same exact make up have a higher density? i have been reading about this for ...
2
votes
1answer
105 views

Estimate the difference between two sets of atoms

I've been working on amorphous structures derived from a crystalline one (using MD) containing $N$ atoms. I want to prove that these structures are different and to quantify their "differentness". One ...
4
votes
2answers
353 views

Which is the lightest thing in this universe? Is that a photon or neutrino?

I hear a lot of people saying that neutrino is the lightest subatomic particle but according to me a photon must be the lightest as nothing can travel faster than light because it gets heavier and ...
1
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2answers
29 views

Possiblity of predicting behavior of system when properties described as functions over space?

Suppose I am given a system that consists of a distribution of charged particles(which are all over space and are point-charges). They are described by a set of functions instead of variables. These ...
2
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0answers
58 views

Time and particles [closed]

What it is in basic particles that make them propagate themselves through time or, basically, what brings that property known as Duration in a particle (wave)? I sense that this is somehow is based ...
0
votes
0answers
18 views

How does one determine the breakdown voltage of a solid-in-liquid suspension?

So I'm doing a project in which we are supposed to collect micro-scale conducting metal particles from a suspension of it in water (which is deionized). Suppose that I am charging the particles ...
0
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4answers
45 views

Can the term «shadow» pertain to anything else than light? [closed]

Can the term shadow pertain to anything else than light? Feel free to interpret this question in the widest sense possible.
13
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1answer
280 views

As the universe expands, the wavelengths of photons are stretched, and energy is lost. What about electrons?

Will electrons, and other particles, also loose energy as they travel through the cosmos? They have wavelengths. Do they get "stretched"? My guess is that the EM force, somehow, counteracts this ...
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0answers
35 views

Books on collision probability and collision processes

Are there any books specifically on collision processes between atoms and molecules and collision probability? I would like to get an overview of the factors that determine collision probability ...
21
votes
4answers
2k views

Can one obtain free energy from the vacuum?

It is known that from the vacuum of a quantum field theory, virtual particle pairs are created and destroyed; is it possible to capture these particles thus obtaining free energy from the vacuum?