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2
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3answers
146 views

What is a particle?

I posted this elsewhere also and just found this place so copied it down but yeah. I've always wondered this cause I like wondering bout things but I wanna know and it's simple so I should. I got an ...
1
vote
1answer
65 views

How much smaller will be human body, when we hypothetically get of every space between particles [closed]

I had an interesting dream, where advanced civilization compress their body with technology, that turn off space betweens atoms/particles. They travel in small spaceship with billions citizens very ...
0
votes
2answers
38 views

The speed of light, objects moving against each other and the effects of a clash

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 constant speed of light (as a ...
4
votes
2answers
47 views

Do mechanical waves travel in straight lines?

Electromagnetic waves travel in straight lines but do all waves travel in straight lines?
0
votes
1answer
130 views

Why do we assume that Dirac spinor $\Psi$ describe the particle, not the field?

It is a well-known fact that Klein-Gordon scalar $\Psi(x)$, $$ (\partial^{2} + m^2) \Psi (x) = 0 $$ as well as 4-vector $A_{\mu}(x)$, $$ (\partial^{2} + m^{2})A_{\mu} = 0,\quad ...
16
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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?
1
vote
1answer
96 views

What kind of a particle has this mass?

I have a particle that has a mass around $(760\pm10)~MeV/c^2$ but I do not know what kind of particle it is. This links me to some tables that have data on all sorts of subatomic particles but it is ...
0
votes
1answer
77 views

Do particles rotate around themselves or they just move while the object rotates?

In this question, I'm not talking about particle spin. I guess, when an object rotates, its atoms also rotate. When an atom rotates, its particles must move in space. I wonder that if the particles ...
8
votes
2answers
2k views

Which is the smallest known particle that scientists have actually *seen with their eyes*? [closed]

Which is the smallest particle that has been actually seen by the scientists? When I say "actually seen", (may be using some ultra advanced microscope or any other man made eye, using any wavelength ...
5
votes
2answers
146 views

How do collisions of fundamental particles produce different fundamental particles?

When considering fundamental particles as waves in fields, it seems like any collision of two particles of some fundamental type could only create energy within that type's field. Why do we expect ...
1
vote
2answers
48 views

How does particles gain electrical charges and repel each others? (electrostatic stabilization)

When I study electrostatic stabilization, I understand that the particles have same charge and thus repel others, this is how colloid is stabilize. But how does particles gain electrical charges and ...
1
vote
1answer
38 views

Why does Se-82 undergo double beta decay?

Looking at the decay chain, I saw it undergoes double beta decay. How is it feasible for something to undergo a simultaneous double decay?
2
votes
2answers
89 views

What is the difference between a charged rho meson and a charged pion?

They both seem to have the same quark content: $$\rho^{+} = u\bar{d} = \pi^{+}$$ and $$\rho^{-} = \bar{u}d = \pi^{-}$$ What is different about the two?
-4
votes
2answers
257 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 ...
3
votes
0answers
34 views

Alternative ways to take particle tracks photographs in a cloud chamber

I know that the most common type of particle tracks photography is in photographic plates, but i'm using a cloud chamber and I would like to know if there are alternative ways to take photographs of ...
1
vote
3answers
148 views

Does the Universe have finite number of particles? [duplicate]

I read that the number of atoms in the entire observable universe is estimated to be within the range of $10^{78}$ to $10^{82}$. Does the Universe have finite number of particles? If so, how could it ...
6
votes
2answers
178 views

If electrons behave as standing waves when they are bound to an atom then how do they carry charge?

Today in my physics lesson we learnt that the best way of describing the behaviour of an electron that is bound to an atom is to treat it as a standing wave. I understand that this is the ...
2
votes
0answers
32 views

Twisted supermultiplets

What is a twisted supermultiplet, in a generic supersymmetric theory? Which ordinary fields belong to one of such twisted supermultiplets? I am confident with the idea of a supermultiplet or a ...
5
votes
2answers
1k views

Magnetic force doesn't do work and therefore can't change the KE of a particle?

I am having a real hard time understanding the principles behind a question I've come across during test prep. Here is the question: Q: A proton and an electron are traveling in the uniform ...
1
vote
1answer
38 views

What is the “inner” force behind attracion/repulsion?

First of all, I'm sorry for any grammatical big error - English is not my native language. I have a question that maybe does not have an answer beyond those which we already have, but maybe there is ...
1
vote
1answer
78 views

What is the state of the art in particle detection and localization

I am researching methods to detect the position of radioactive materials (emitting gamma and beta particles), and would like to know what current methods are used to do this. What type of sensors are ...
1
vote
2answers
138 views

From where does a particle get the energy to tunnel?

When a particle is made to confine more and more to a particular position it breaks the energy barrier to get out because of the uncertainty principle. But, from where does the particle get the energy ...
1
vote
2answers
157 views

Classical point particles to classical fields

I often hear that in the continuum limit we can study large numbers of particles as fields. I always imagined that by removing all bounds on the number of particles (while keeping total energy, ...
4
votes
2answers
142 views

What information is lost in the symmetrization necessary to derive the BBGKY hierarchy?

The book on Kinetic theory I'm reading derives the BBGKY hierarchy after introducing the reduced distribution functions $f_s(q^1,p_1,q^2,p_2,\dots,q^s,p_s):=\int\ \rho\ \ \mathrm d q^{s+1} \mathrm d ...
2
votes
1answer
42 views

Experiment dropping electrons into glass of protons

So, when you drop dye into a glass of water the dye spreads out. Now I realize you cant simply replace the water in the glass with protons (or a pure concoction of electrons) but I am wondering... ...
1
vote
1answer
71 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 ...
3
votes
3answers
130 views

Will the current carrying solid conductors emit light?

If we pass current through a gas, like in the discharge tube, the electrons will accelerate in the electric field. The accelerated electrons will collide with gas molecules, and transfer some of their ...
1
vote
2answers
181 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 ...
2
votes
2answers
92 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
votes
2answers
97 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 ...
1
vote
1answer
407 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, ...
2
votes
1answer
103 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
votes
1answer
110 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
votes
2answers
245 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 ...
9
votes
1answer
250 views

Why are there no particles in conformal theories?

In Matt Strassler's recent post (here) he makes the statement that scale invariant (I assume he means conformally invariant, more generally) theories have no particles in them. What's the reason for ...
2
votes
3answers
9k 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
votes
1answer
140 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
vote
0answers
41 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
votes
0answers
98 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
votes
3answers
279 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
votes
2answers
337 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
vote
2answers
181 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?
0
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0answers
390 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
votes
1answer
95 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 ...
0
votes
3answers
434 views

Can every particle be regarded as being a combination of Black holes and White holes?

Can the statement be regarded as true? That every particle, or element in the universe can be regarded as a combination of black hole and white hole in variable proportion.
11
votes
1answer
3k 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
votes
1answer
146 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
votes
6answers
473 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
votes
0answers
58 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 ...
3
votes
3answers
1k 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 ...