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Feb2313 08:41 AM
ZapperZ

1 
21,052 
God particle is 'found': Scientists at Cern expected to announce on Wednesday Higgs boson particle has been discovered...

Jul1112 01:13 AM
tom.stoer

178 
34,419 
I read it some where that there is very small decoherence for photons. The reason being that photons do not interact...

T 12:15 PM
Halaaku

0 
15 
Ive attached the R ratio formula to this post, please could someone who is familiar with it tell me what Nc is?
...

T 07:19 AM
rwooduk

4 
102 
What are the lowest energy transmutation caused by a neutrino and an antineutrino respectively?

Y 09:00 AM
Vanadium 50

7 
215 
Is there something like a "neutrino spectrum"?.
Would it be analog to light spectrum?.
Sorry for the ignorance, just...

Apr1814 07:58 PM
kurros

3 
254 
Hi,
I am just learning some materials and struggling to find what the other octet is. I know the following:
3...

Apr1814 09:37 AM
Bill_K

1 
232 
All the Feynman diagrams I have seen so far for a neutron colliding with a neutrino have a w+ with an arrow from the...

Apr1814 09:26 AM
mfb

3 
230 
So I'm trying to show that one choice of representation for the SuSy generators fulfills the SuSy algebra.... (one of...

Apr1814 07:11 AM
andrien

4 
279 
What is the Decay Width of a particle and how is it related to the particle's lifetime ?

Apr1814 06:19 AM
UltrafastPED

1 
159 
Hi folks  does anyone know of a proof that particle (quanta) number in QFT is / is not Lorentz invariant? I'd be...

Apr1714 03:53 PM
Mordred

20 
559 
I know that fermions and bosons can thermodynamics can be calculated via the Fermidirac or Bose_Einstein...

Apr1714 01:54 PM
Mordred

4 
246 
i've looked online and the closest i've found to a definition is this:
what does this mean? i understand that...

Apr1714 07:21 AM
rwooduk

3 
291 
This is related to a homework problem but I want to understand it as well. How can a proton break up into a positron...

Apr1614 11:14 AM
metamathphys

3 
369 
Hi all,
I'd like to know how the chiral symmetry protect the electron mass in the oneloop calculation of the...

Apr1614 10:09 AM
andrien

1 
244 
Hi Folks,
We use a UV bulb in my workplace which contains deuterium gas. The bulb is safely contained within a...

Apr1514 06:04 PM
teaforone

4 
295 
Hi folks,
I've been reading about MontonenOlive duality and understand that two different classical theories can...

Apr1514 03:52 PM
metroplex021

0 
218 
Consider
e+e* > q+q* in the centre of mass frame. Where I am using star for antiparticle.
the quark and anti...

Apr1514 07:11 AM
RGevo

9 
433 
I'm looking at charmonium and its decays. Given a list of data on the charmonium states I'm asked to say why ψ'' has...

Apr1414 07:20 AM
Einj

2 
307 
Hi all,
I have a couple questions about radiation from radioactive elements. I've read a lot of articles on the...

Apr1314 10:46 PM
Simon Bridge

9 
400 
Hi.
This may be a trivial question, but I'm unable to find a definitve answer.
How is the mass on a atomic...

Apr1214 06:01 PM
bcrowell

4 
313 
Why are exited states of an Isotope metastable? Is it because they have a large spin and therefore the final states...

Apr1214 10:00 AM
mfb

4 
412 
I came across a worked example question in a particle physics book this morning that had a beam of neutrinos of energy...

Apr1214 03:34 AM
Naz93

3 
361 
So i have a question regarding a homework question i'm working on which suggest a neutral pion travelling with...

Apr1114 05:55 PM
mfb

2 
275 
I read this on a website called Physics for Idiots
"If an electron gets near another electron it emits a virtual...

Apr1114 04:06 PM
mfb

6 
539 
Hi everyone. I have been studying CP violation in kaon systems. I would like to know is someone can explain why, to...

Apr1114 02:16 PM
Einj

6 
328 
I am trying to derive the conserved charge from the symmetry of the action under Lorentz transformations, but I am...

Apr1114 02:04 PM
samalkhaiat

5 
333 
I'm learning about particle physics at the moment, and have read that the J=3/2 multiplet contains baryons comprised...

Apr1014 01:50 PM
Naz93

3 
341 
In SM, people say the ##SU(2)\otimes U(1)## theory unify the EM and weak interaction. I understand that the two...

Apr1014 12:35 PM
clem

2 
318 
I don't completely understand why an electron positron pair cannot be created from an isolated photon. I understand it...

Apr1014 07:59 AM
ofirg

10 
369 
Hi, I'm in the process of revision for upcoming exams, one likely question will give a number of decays (~5) and ask...

Apr1014 06:37 AM
rwooduk

6 
336 
1) Since Wigner it is well known that for massless particles of spin s the physical states are labelled by helicity h...

Apr914 10:37 PM
strangerep

67 
5,343 
How can we determine the ranges of strong interactions and weak interactions?
Can calculations of relevant scattering...

Apr914 09:36 PM
Simon Bridge

4 
325 
Hi. I was reading Griffiths page 289 and I wasn't sure how the transition from Eq. (8.45) to (8.46) was allowed. What...

Apr914 07:20 PM
spookyfish

2 
285 
Why is the chiral symmetry breakdown determined for the vector/axial current as:
V =...

Apr914 05:07 PM
The_Duck

1 
284 
THREAD CHANGE *SPINOR IDENTITY*...although it's connected with SuSy in general, it's more basic...
I am trying to...

Apr814 03:28 PM
andrien

3 
388 
The Monte Carlo simulation is a very important tool in particle physics specially to tune in the preciseness of the...

Apr814 02:33 AM
RGevo

3 
504 
I mean Goldstone bosons in the title. Sorry I don't know how to edit the title.
Goldstone's Theorem says that...

Apr714 10:22 PM
karlzr

10 
554 
I have two related questions to ask relating to statements found in introductory particle physics textbooks.
The...

Apr514 05:15 PM
Bill_K

1 
374 
Hello, I need some help understanding the possible decays of buttomonium b\bar{b}.
If I consider weak and...

Apr514 10:52 AM
kuecken

2 
519 
I'm not sure if I can ask this question clearly, but anyway...
We have this collection of 17 or so particles. Some...

Apr514 06:27 AM
mfb

9 
561 
Hi all,
I've been seeing this again and again, that delayed neutrons are the ones that are allowing thermal nuclear...

Apr414 05:58 PM
mfb

7 
426 