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62
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5answers
13k views

What does it mean for two objects to “touch”?

If you've ever been annoyingly poked by a geek, you might be familiar with the semi-nerdy obnoxious response of "I'm not actually touching you! The electrons in the atoms of my skin are just ...
14
votes
1answer
4k views

Are all electrons identical?

Why should two sub-atomic (or elementary particle) - say electrons need to have identical static properties - identical mass, identical charge? Why can't they differ between each other by a very ...
11
votes
4answers
2k views

Why does amount of protons define how matter is?

My question might sound convoluted but my mind is twisting right now so my apologies in advanced. Why is it that when I have one proton and one electron it is Hydrogen a clear flammable gas, and ...
8
votes
2answers
22k views

What is in the space between a nucleus of an atom and its electrons?

There is a common analogy about the structure of an atom, such as the nucleus is a fly in the centre of a sports stadium and the electrons are tiny tiny gnats circling the stadium (tip of the hat to ...
8
votes
4answers
1k views

Huge confusion with Fermions and Bosons and how they relate to total spin of atom

I am supremely confused when something has spin or when it does not. For example, atomic Hydrogen has 4 fermions, three quarks to make a proton, and 1 electron. There is an even number of fermions, ...
7
votes
1answer
729 views

Anti-Matter for Neutrons

The anti-particle corresponding to a proton or an electron is a particle with an equal mass, but an opposite charge. So what is the anti-particle corresponding to a neutron (which does not possess a ...
6
votes
2answers
652 views

Miniature Neutron Stars?

Is the nucleus of a carbon atom, for example, as dense as a neutron star? I read that neuton stars also contain protons. Thinking more broadly, are we surrounded by quadrillion of quadrillions of ...
6
votes
4answers
1k views

Intrinsic structure of electron

The electron contains finite negative charge.The same charges repel each other.What makes electron stable and why does it not burst? Is it a law of nature that the electron charge is the smallest ...
5
votes
2answers
478 views

How many subatomic particles can absorb/emit photons?

Is the electron the only subatomic particle that can absorb and emit a photon?
5
votes
2answers
1k views

The Nucleus of an Atom

We know that the protons in a nucleus are positively charged, whereas the neutrons do not possess a charge; we also know that unlike charges attract. So why does the nucleus stay intact, even though ...
5
votes
1answer
1k views

Why are there 3 quarks in proton?

A few quark related questions (I don't knowmuch about them other than there are 2 flavours concerning protons and neutrons) Why are there 3 quarks in a proton or neutron? Why not 2 or 4? Is there an ...
5
votes
1answer
83 views

What does energy represent in $E= mc^2$?

Due to energy-mass equivalence, any object with mass can be said to have a corresponding amount of energy. So in a 5kg object there are 450,000,000,000 joules. A joule as i understand it is the ...
4
votes
1answer
2k views

Why are electrons and quarks 0-dimensional?

Disregarding String Theory, which says that electrons and quarks are 1-dimensional, why are electrons and quarks 0-dimensional? The way I look at it is that they have mass, and if we were the same ...
4
votes
2answers
183 views

Are nodes and orbitals in atoms simply probability distribution clouds or are they of any physical relevance?

I fail to understand what the electron clouds actually signify. Such as the $p$ orbitals, which have a dumbbell like shape. Now I am aware that they aren't actual trajectories of electrons, but what ...
3
votes
2answers
195 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?
3
votes
1answer
181 views

Paramagnetism what about Paraweakism or Parastrongism?

Ok, I was just curious but the electromagnetic force can allow paramagnetism macroscopically in some objects. Can this be done microscopically to the subatomic level? Also, what about other forces ...
2
votes
2answers
213 views

What is the reason for the electrons in a given subshell to orient in certain preferred regions?

My text book says: "Magnetic quantum number describes the behavior of electron in a magnetic field. We know that the movement of electrical charge is always associated with magnetic field. Since ...
2
votes
1answer
489 views

Explanation on Atomic Orbitals and Molecular Orbitals

We were reading about atomic structures and bond making and my teacher told me that when two atoms are fused or when they make bond, two orbitals are formed. 1-Bonding Molecular Orbital & 2- ...
2
votes
2answers
556 views

Looking for a list of possible subatomic particle collisions

This is going to be a strange question, but here we go. I'm working on a computer puzzle game that will simulate subatomic particle collisions. I am not a physicist by training, but I do dabble. I ...
2
votes
2answers
61 views

Why is water blue (on a quantum level)

OK, lets formulate it differently and say water works as a blue passing / red restricting filter. It is actually observable. Just do a dive in a swimming pool with white light (maybe even at night) ...
2
votes
2answers
1k views

Alpha particle and helium nucleus

The symbol for the alpha particle is α or $α^{2+}$, it can be written as $He^{2+}$. What I want to know is that, are they same? I mean alpha particle and helium nucleus are same or any subtle ...
1
vote
3answers
536 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 ...
1
vote
2answers
418 views

Does the fact that protons and neutrons have larger mass than electrons mean they're bigger in size?

and so if a proton is so larger than an electron doesn't that mean it has a shape? What would be the shape of a subatomic particle? are they spherical?
1
vote
1answer
55 views

How we can manipulate the momentum of a particle?

Is there any way to affect a particle's momentum value?
1
vote
2answers
339 views

How exactly do protons and electrons interact with each other?

How do these particles exchange information about charge and position between themselves, even though there's mostly empty space between them? Also what happens if a free electron passes closer to a ...
1
vote
2answers
137 views

Has a photon or electron ever been observed in a state of superposition?

Has subatomic particles ever been seen in a state of superposition or do we just detect information like qubits about the state of the particle? So is actual matter in superposition or is it just ...
1
vote
1answer
77 views

What would be the effect of an excess of up quarks on stellar formation?

Suppose you had 80% up quarks, and only 20% down quarks. How would this affect stellar formation?
1
vote
2answers
323 views

How can particles being closed strings in String Theory create solidity in objects?

I understand how particles with certain masses can form to make atoms, which create solidity in objects due to Pauli's Exclusion Principle and what have you. These particles actually have mass and to ...
1
vote
1answer
61 views

Why don't we have more elements?

By looking at the number of subatomic particles there seem to exist, there should be thousands of element configuration combinations possible. But we have found just over hundred elements to exist. ...
1
vote
2answers
138 views

Can protons in the nucleus of an atom be aligned by electromagnetic fields?

Can protons in the nucleus of an atom be aligned by electromagnetic fields? If so can it be done around $-135°C$ zero?
1
vote
1answer
140 views

The Value of Newton's Gravitational Constant $G$ within an Atom

Can the value of Newton's Gravitational Constant $G$ be measured within a stably bound atom? PLEASE NOTE: Since scattering experiments do not involve stably bound systems, their results are not ...
1
vote
1answer
96 views

Atomic physics question - exciting of electrons during bonding

As I have learnt, when bonding takes place in an atom, such as carbon, the electron in its $s$-subshell gets excited and jumps to the open spot in the $p$-subshell. This is why carbon is able to form ...
1
vote
1answer
42 views

Nuclear fission mechanism: neutron capture

Consider this nuclear fission reaction: $\mathrm{^{235}U+{}^1n\to{}^{236}U \text{ (excited)}\to{} ^{92}Kr+{}^{141}Ba+3{}^1n}$ I have not understand why a thermal neutron ($^1$n with $E\simeq 0.025$ ...
1
vote
1answer
127 views

Are subatomic partices n-dimensional hyperspheres or another n-dimensional shape?

This guy derives the formula for the volume of an n-dimensional hypersphere, which can also be found here on the Wikipedia page, and he shows that it is equal to this equation: $V_n = ...
1
vote
1answer
629 views

How to determine how many atoms are in something?

I want to know if it's possible to find out how many atoms are in something, and how one would do that. For example, how many quarks are in my brain(easy to find out once you know how many atoms there ...
1
vote
2answers
157 views

What's the difference in subatomic structure between a conductor and a non-conductor?

I mean, some elements don't conduct electricity, while some do. They are all atoms, and electricity is always electrons. So why won't it flow sometimes, and why does it flow in other times?
1
vote
0answers
39 views

Subnuclear physics vs wave function

This question is more a philosophical question than a physics one. When we appreciate particle physics we study that in order to explain some experimental results we have to introduce a new particle ...
1
vote
0answers
46 views

What does it mean for a subatomic particle to “have” energy?

From my limited classical interpretation of the universe, i've always found it convenient to think of energy as what happens when an object isnt in its equilibrium position in the universe, and thus ...
1
vote
0answers
51 views

Fluidic gravity, TOE, what's your oppinion on this research? [closed]

It's interesting because we don't normally consider the "vaccuum of space" as a fluid, but it's becoming more apparent that it's an ocean of subatomic stuff. Here's a link to a book: Unified Fluid ...
1
vote
0answers
49 views

Benefits of the sign convention for electrons?

Benjamin Franklin considered electrons to be positive, but J.J. Thompson considered them negative. We obviously went with J.J. Thompson's convention. Why? What were the benefits of moving to J.J. ...
1
vote
0answers
119 views

Proton scattering off electrons

I'm looking at a question which starts off as: A proton is travelling through a material and scattering the electrons in the material. Express the scattering angle in terms of the impact parameter, ...
1
vote
0answers
31 views

How can we know about particle spin? [duplicate]

Possible Duplicate: How does one experimentally determine chirality, helicity and spin? This is a rough quite from Hawking: "An elementary particle with 0 spin looks the same no matter ...
0
votes
6answers
674 views

What would be likely to completely stop a subatomic particle assuming it was possible?

Suppose that completely stopping a subatomic particle, such as an electron, could happen under certain conditions. What would be likely ways to get an electron to be perfectly still, or even just stop ...
0
votes
1answer
13k views

What did Marie Curie do for atomic theory?

There appears to be a distinct lack of agreement in the physics community on what exactly Marie Curie did for atomic theory. Many journals state that Curie was responsible for shifting scientific ...
0
votes
3answers
106 views

Do nanoscopes exist?

We are mostly all familiar with a microscope, and know that it helps to see MICRO components, like stuff that is photolithographically etched on silicon semiconductor die. (The latter can also be ...
0
votes
2answers
390 views

Do electrons have a radius when they behave like a particle?

I know sometimes electrons behave like waves, but it sometimes can be seen as a particle. while it's a particle, does it have a radius? or, a volume? If it doesn't even have a volume, how can we still ...
0
votes
1answer
50 views

quarks annihilation process

I am appreciating particle physics and I read about mesons. In quark's model, mesons are pairs of quark-antiquark. Now I think that in general matter-antimatter annihilate and so I don't understand ...
0
votes
1answer
308 views

How to determine the amount of light energy (photons) being released from an incandescent light bulb?

I have got this all down pat: 1.Collision with a moving particle excites an atom. 2.This causes an electron to jump to a higher energy level. 3.The electron falls back to its original energy level, ...
0
votes
1answer
104 views

how do they rip one single atom from something?

this is simple. what i actually want to ask is, when they do the subatomic particle collision experiments, how do they produce one single subatomic particle, e.g proton, neutron? how do they rip one ...
0
votes
1answer
2k views

How can I calculate out the 'specific charge' of an atom? [closed]

I know that it's charge/mass. But what steps do I take to calculate the specific charge of say, carbon-12? What about ions too?