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1answer
180 views

How is a Higgs boson created?

I have read a lot on Higgs bosons, yet I do not fully comprehend how they are created and how they are "flicked off" the Higgs field. I have also had trouble comprehending why a Higgs boson quickly ...
0
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2answers
337 views

Does our existence cost us energy?

Anything when it needs to inform its presense such as electromagnetic presense of charged particles and gravitational presense of particles due to their mass does so by sending information of its ...
1
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2answers
125 views

What distinguishes the particles we chose as matter from their antimatter equivalent? [duplicate]

Back before we knew about antimatter we just called everything matter. Ignoring CP-violation for a moment, there is nothing special about matter versus antimatter. Once we knew about antimatter it ...
6
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2answers
111 views

Deciding what to collide at particle accelerator

Different particle accelerators use different types of collisions. For instance at the LHC they investigated p Pb collisions while its predecessor (LEP), used to collide electrons with proton and at ...
2
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1answer
122 views

Particles from String theory

I understand that the strings in string theory are posited to be many, many orders of size smaller than say, a quark, electron or any other particle. But if this is so, how does the string "expand" to ...
0
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1answer
155 views

Particle Spacing in a Vacuum

Four questions: (To start off, I know very little about physics it isn't even funny (I probably use a ton of wrong terms here and leave out vital information, if so I will try to edit it in as you ...
5
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2answers
298 views

Is ch. 2, sect. 4 of The Feynman Lectures on Physics, Vol. 1 still accurate?

The chapter 2 section 4 of volume 1 is on nuclei and particles. Here are a few things that trouble me. Dr. Feynman says that Another most interesting change in the ideas and philosophy of science ...
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3answers
19k views

How to deduce E=(3/2)kT?

It says in my course notes that a particle has so-called "kinetic energy" $E=\frac{3}{2}kT=\frac{1}{2}mv^²$ Where does this formula come from? What is k?
2
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1answer
167 views

Can you tell if a particle is in superposition?

This may be an easy answer for anybody. Is it possible to detect if a particle A is still in a superposition via the sending a group of particles B through a box containing particle A?
1
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0answers
61 views

How do I build an alpha emitter?

I would like to build an alpha emitter. I suppose I had some vague idea of knocking the electrons off of some helium. But upon further examination the idea does strike me as...naive? My question is ...
0
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0answers
126 views

What the quantum spin refers to? How we calculate the angular momentum $\omega$ from the spin quantum number?

How we calculate the angular momentum $\omega$ from the spin quantum number, to know how fast a particle rotating on its own axis?
7
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3answers
321 views

Is particle number a problem for formulating statistical physics in a mathematically rigorous manner?

Quantities like the chemical potential can be expressed as something like $$\mu=-T\left(\tfrac{\partial S}{\partial N}\right)_{E,V}.$$ Now the entropy is the log some volume, which depends on the ...
3
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2answers
699 views

Particles vs Waves

As I remember long ago, in my physics classes, I always had a great trouble understanding the concept of waves. Our professor used to explain, as if everything in this world is made up of waves. ...
1
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2answers
681 views

Particles and their charges [duplicate]

It is always known that electrons and protons have opposite charges but what gives electrons or protons the charges they have?
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0answers
2k views

Statics: particle mechanics versus rigid body mechanics

In particle mechanics where the notion of rotation does not apply, particles are said to be in static equilibrium when the sum of the external forces acting on the particle of interest in all ...
0
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1answer
107 views

Storing kinetic energy in bonds

Let's assume a setup with a static linear molecule with three identical atoms connected by bonds and a single atom, identical to the other three, being shot at the molecule. Let's also assume that ...
13
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1answer
5k views

Phase shifts in scattering theory

I have been studying scattering theory in Sakurai's quantum mechanics. The phase shift in scattering theory has been a major conceptual and computational stumbling block for me. How (if at all) does ...
-2
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1answer
303 views

Does the particle vibrate in 3D space? [closed]

As far as I know, particles vibrate with a frequency and wavelength determined by their energy level. Is this vibration in 3D space?
5
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6answers
677 views

What needs to happen for one to ingest radioactive particles and how likely is this?

There are many stories about radioactivity and the relative danger of it in the news lately, but very little actual information. The radioactivity levels around Fukushima Daiichi are high, but seem ...
0
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0answers
67 views

Preons and 't Hooft condition

If some fundamental particles, like leptons or quarks are composite (e.g.in preonic models), or the same with gauge bosons or the higgs particles. How could it be possible that preons were more ...
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3answers
2k views

Writing wave functions with spin of a system of particles

Suppose I have 2 fermions in a potential $V(x)$. Both particles are moving in one dimension: the $x$ axis. Then, neglecting the interaction between the particles, the spatial wave function of the ...
0
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1answer
184 views

Can we see light as it 'interferes' with itself and produces the characteristic double-slit pattern?

This TED talk suggests that we can now watch as a beam of light propagates through a bottle filled with water. My question is: can we use this new technology to perhaps 'see' the photon as it makes ...
3
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1answer
117 views

What is the $t\bar{t}$ production supposed to bring up

The $t\bar{t}$ production, I've read, that will somehow confirm the QCD and might bring up new physics. Why are we studying $t\bar{t}$ production from $p-p$ collisions at the LHC? What are we trying ...
5
votes
1answer
1k views

Confusion between the de Broglie wavelength of a particle and wave packets

So I learned that the de Broglie wavelength of a particle, $\lambda = \frac{h}{p}$, where h is Planck's constant and p is the momentum of the particle. I also learned that a quantum mechanics ...
2
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1answer
122 views

Uncertainty Principle on System of particles

I am new to Quantum Mechanics. I read the uncertainty principle - it says there are pairs of physical quantities which can't both be determined with certainty for a particle. My question is does the ...
1
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0answers
45 views

Acceleration by spherical particles (micron-scale) by an external force

I am looking for an expression for the velocity of a micron sized (1 - 10 micron diameter) sized particles under accelerating forces. I have aerosols in mind. This is what I have in mind The ...
7
votes
2answers
1k views

Do particles and anti-particles attract each other?

Do particles and anti-particles attract each other? From the very basic understanding that they are created out of nothing mutually and collide to annihilate each other seems to indicate this happens ...
3
votes
1answer
124 views

Convolving Parton Distribution Functions

I have the cross-sections as a function of $\sqrt{s}$ for a process with a $u$-quark and $u$-antiquark in the initial state (eg.: $u \bar{u} \to e^- e^+$). I have a standard parton distribution ...
5
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2answers
499 views

What if a faster-than-light particle is found?

What will be the consequence (severe ones) on laws of physics if a particle that travels faster than light is discovered? I am looking for a more general answer so that a high school student would be ...
1
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0answers
101 views

Do particles travel backward and forward in time? [duplicate]

All these classical ideas are pointless and obsolete today, because in quantum mechanics, the particles are completely different objects, defined by quantum motion of fields, not by the location of ...
0
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2answers
244 views

Why is electron presented in books, pictures as a sphere?

Why is electron presented in books, pictures as a sphere, when in fact it's not?
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2answers
234 views

Does the unpredictability in the “micro world” means that everything is if we can look at it close enough imperfect?

Does the unpredictability in the "micro world" means that everything is if we can look at it close enough imperfect? I mean, there is a saying "You will never stand in the same river again" or ...
2
votes
2answers
215 views

Why does the amplitude of a ripple tells us that it is a particle?

The quote below is from Matt Strassler's blog: a particle is a ripple with many crests and troughs; its amplitude, relative to its overall length, is what tells you that it is a single ...
2
votes
2answers
9k views

Frequency of an Electron

My question is very simple. If frequency is defined as the cylces per unit time, Then what is meant by "Frequency of an Electron" ? If the rotation of electron around a nucleus is considered then, ...
0
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2answers
149 views

Can energy be defined as the most fundamental particle which exists in different forms as protons, electrons etc

What we see all the different forms of matter around is just a form of energy. Why can't this energy be the most fundamental particle. Given dust can turn into a star and then emit all sorts of ...
0
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1answer
155 views

Is the idea of dividing the universe into particles anything more than an untrue convenience? [closed]

In theory, we speak of a particle as having properties. In reality, the measurement of any property is just an interaction between the target to be measured, and the measuring apparatus, where the ...
2
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2answers
207 views

Is there a map of the particles in outer space?

Since outer space is not quite a vacuum, and the distribution of various heavenly bodies is locally inhomogeneous, it seems reasonable to expect that the density and variety of particles ...
1
vote
1answer
260 views

Lifetimes of stable particles

What are possible lifetimes of up/down quarks, electronic/muonic/tau neutrinos, photon, gluon? I understand they are said to be stable, but, as I saw on wikipedia, the lower bound for the "stable" ...
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2answers
2k views
1
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3answers
383 views

Do particle pairs avoid each other? Please end my musings

Can you explain what happens when a particle and its antiparticle are created. Do they whiz away from each other at the speed of light or what? I suppose that they don't because otherwise they would ...
3
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2answers
4k views

Speed of a particle in quantum mechanics: phase velocity vs. group velocity

Given that one usually defines two different velocities for a wave, these being the phase velocity and the group velocity, I was asking their meaning for the associated particle in quantum mechanics. ...
3
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2answers
203 views

How can Sub-Atomic Particles be Visualized?

Can you see or accurately visualise sub atomic particles or are they known only by maths and/or inference?
4
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1answer
239 views

Temporal part of Quantum Wavefunction

I was hoping that someone could give me the more fundamental reason that we take as the temporal part of a quantum wavefunction the function $e^{-i\omega t}$ and not $e^{+i\omega t}$? Clearly ...
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6answers
1k views

What is the meaning of the word “particle” in particle physics?

I want to use Matt Strassler's definition of the word "particle" as a specific example: Matt Strassler writes: (1) "...all the elementary “particles” (i.e. quanta) of nature are quanta of waves ...
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4answers
1k views

How can/does calculus describe the movement of a particle?

I was talking to Roger Penrose about calculus in the appendix in his book Cycles Of Time and he said I'd need a good understanding of calculus if I wanted to read his book in great depth. He said I ...
1
vote
1answer
604 views

Definition of elementary particle [duplicate]

Possible Duplicate: Why are atoms particles? According to wikipedia an elementary particle or fundamental particle is a particle not known to have substructure. Moreover, I've learned ...
2
votes
1answer
186 views

$sss$ decay and violation of strangeness

Why can the hyperon $\Omega^{-}$ not decay by strong interaction? It seems that strangeness must be violated, but why is it the only way?
7
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1answer
400 views

Why doesn't my particle simulation end in a flat disc?

I've made a 3d particle simulator where particles are attracted to each other by the inverse of the square radius. The purpose of my experiment is to see if this alone would create a flat disk (like ...
3
votes
2answers
220 views

Understanding a Physics Paper on Quantum Teleportation of Continuous variables

The paper I am trying to understand is here: http://pra.aps.org/abstract/PRA/v49/i2/p1473_1 The paper describes the quantum teleportation protocol in a general case with continuous dynamical ...
0
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1answer
172 views

Would synchronized dancing be a good way to describe entangled atoms to a laymen?

I was talking my professor about entanglement swapping between light and matter and it is briefly described here: You start out with a crystal capable of doing parametric down conversion of incoming ...