In quantum mechanics, a boson (, ) is a particle that follows Bose–Einstein statistics. Bosons make up one of two classes of elementary particles, the other being fermions. The name boson was coined by Paul Dirac to commemorate the contribution of Satyendra Nath Bose, an Indian physicist and professor of physics at University of Calcutta and at University of Dhaka in developing, with Albert Einstein, Bose–Einstein statistics, which theorizes the characteristics of elementary particles.Examples of bosons are fundamental particles such as photons, gluons, and W and Z bosons (the four force-carrying gauge bosons of the Standard Model), the recently discovered Higgs boson, and the hypothetical graviton of quantum gravity. Some composite particles are also bosons, such as mesons and stable nuclei of even mass number such as deuterium (with one proton and one neutron, atomic mass number = 2), helium-4, and lead-208; as well as some quasiparticles (e.g. Cooper pairs, plasmons, and phonons).An important characteristic of bosons is that there is no restriction on the number of them that occupy the same quantum state. This property is exemplified by helium-4 when it is cooled to become a superfluid. Unlike bosons, two identical fermions cannot occupy the same quantum state. Whereas the elementary particles that make up matter (i.e. leptons and quarks) are fermions, the elementary bosons are force carriers that function as the 'glue' holding matter together. This property holds for all particles with integer spin (s = 0, 1, 2, etc.) as a consequence of the spin–statistics theorem.
When a gas of Bose particles is cooled down to temperatures very close to absolute zero, then the kinetic energy of the particles decreases to a negligible amount, and they condense into the lowest energy level state. This state is called a Bose–Einstein condensate. This property is also the explanation for superfluidity.
Hi,
i was wondering why a W Boson must always decay into a quark anti quark pair of the same generation. Why can it not for example decay into an up ant anti strange pair?
I am reading the Schwartz's quantum field theory, p.207 and stuck at some calculation.
In the page, he states that for identical particles,
$$ | \cdots s_1 \vec{p_1}n \cdots s_2 \vec{p_2} n \rangle = \alpha | \cdots s_2 \vec{p_2}n \cdots s_1...
Hi everyone!
I'm working on a seminar project on elementary particles, and I'm supposed to introduce the LHC and rediscover the Higgs boson from a dataset I got from CERN open source.
I don't understand how am I supposed to discover the gap (in the invariant mass diagram) around the Higgs boson...
The New Measurement
The ATLAS experiment at the Large Hadron Collider (LHC) has experimentally limited the "width" of the Standard Model Higgs boson with a rest mass of about 125 GeV to 4.5 + 3.3 - 2.5 MeV, with a maximum value of 10.5 MeV at a 95% confidence level.
In the Standard Model, the...
If I put this in technically correct terms, to enable a local symmetry related to electron phase change, we need to introduce a spin 1 field which is identified as electromagnetic field.
Yet there are other spin 1/2 particles. Say, what about neutrino? As it does not couple with electromagnetic...
I think ##X## appears to be ##\pi^{+}## because it is light and energetically more favourable. Pion should be positive to ensure charge conservation. I am stuck at drawing a Feynman diagram for $$p+\bar{p} \to W^- + \pi^+$$.
Is this correct? Is this the leading order diagram or is there a...
Summary: Non-Mathematical Description of the Higgs Boson
I seek a recommendation for a book written for the layman describing the physics of the Higgs boson and related topics. Books that I have found tend towards the history leading up to the discovery of the Higgs or biographies of Peter...
Hi,
I'd request you to keep it simple so it's accessible by a layman.
Question 1:
Is Higgs field made up of Higgs bosons? Higgs field has a positive value everywhere. Other fields such as electron field, hover around zero though virtual particles come into existence and decay almost...
I need to use hermiticity and electromagnetic gauge invariance to determine the constraints on the constants. Through hermiticity, i found that the coefficients need to be real. However, I am not sure how gauge invariance would come into the picture to give further contraints. I think the...
The team has found that the particle, known as a W boson, is more massive than the theories predicted.
The result has been described as "shocking" by Prof David Tobak, who is the project co-spokesperson.
The discovery could lead to the development of a new, more complete theory of how the...
During beta decay an electron and neutrino are emitted at very high speeds. I thought that the electron and neutrino were the product of w boson decay but I recently learned w bosons are over 80 GeV worth of energy. My question is, where does this mass come from? I know that atoms get enough...
If I look at the photon propagator <A_mu (x) A^nu(0) > in momentum space, as I understand it I am to compute this by summing up all the self-energy diagrams of the photon, which look like:
photon -> stuff -> photon
In particular, since the photon shares the same quantum numbers as the Z, you...
Zero spin of Higgs boson? Is it really zero? Where is the spin (intrinsic angular momentum) of the Higgs boson on so small that we quantify it as having zero spin?I am aware of the reduced plank constant. But I we sure there is nothing in between the reduce Planck’s constant and the zero spin of...
Hi,
Please note that I'm trying to understand it at very basic level. I'd really appreciate if you could help me with the queries below.
I was reading this article, https://www.space.com/four-fundamental-forces.html, on the four fundamental forces of nature.
Under the section The weak force...
My question is really about the degeneracies. I know that the symmetrization postulate says that there is only 1 unique ket in the subspace ##Sym^{N}V##, but does this mean that if I know one unique spin configuration that is symmetric, say ##|33>## then is it correct to say the ground state...
Summary:: I would like to ask about books and other materials to study in order to understand in a really, really rigorous manner the Higgs field, Higgs boson and other related topics.
Answers that are detailed but at the same time precise and to the point would be highly appreciated (please...
They seem to have something to do with Z or W particles, maybe, and they have something to do with mediating weak iso spin, I think, and they may be related to the Higgs field. But they don't have a box dedicated to them on the Standard Model of particle physics. Can someone tell me why this is...
Hi guys,
I'm studying my first-year physics in college, and I'm having to write a report of some proton-proton collisions that were registered in the LHC of CERN years ago. The main goal is to identify different bosons (W and Z) that are decaying into other elemental particles. I've been asked...
In the theory of superfluidity, ##^{4}##He atoms are seen as weakly interacting pointlike bosons, with an integer total spin. Does a ##^3##He atom also become a boson if I add or remove one electron to give ##^3##He##^+## or ##^3##He##^-## ?
I'm trying to calculate the ground state wave...
I am a student minor in physics and I am taking this course of particle physics. And I have been lost since the Non-Abelian Gauge Theory which a few lectures before Electroweak unified Theory lecture.
i am completely confused and overwhelmed by the math since the mid-term exam, since I was not...
Hello everyone,
I am stuck in the derivation of the three gauge-boson-vertex in Yang-Mills theories. The relevant interaction term in the Lagrangian is$$\mathcal{L}_{YM} \supset g \,f^{ijk}A_{\mu}{}^{(j)} A_{\nu}{}^{(k)} \partial^{\mu} A^{\nu}{}^{(i)} $$
I have rewritten this term using...
Hello everyone,
I am stuck in deriving the three gauge-boson-vertex in Yang-Mills theories. The relevant interaction term in the Lagrangian is
$$\mathcal{L}_{YM} \supset g \,f^{ijk}A_{\mu}{}^{(j)} A_{\nu}{}^{(k)} \partial^{\mu} A^{\nu}{}^{(i)} $$
I have rewritten this term using the...
The Higgs boson with mass couples to quarks and leptons to give them mass. What was the nature of these particles before they acquired mass? Were they virtual particles?
In Beta+ decay, a W+ boson is created and it decays into positron and electron neutrino. Mass of W+ boson is ~ 80 GeV/c^2, however, the total mass of positron and electron neutrino is very small compared to it. So, what happens to the rest of the mass? Is it converted into kinetic energy of...
This is serious question.
What knowledge can we gain by knowing or understanding the Higgs boson completely? What is the Higgs..
1. Easy problem?
2. Moderate problem?
3. Hard problem?
I need to see the complete lists of it that may be spread in many obscure papers in Arxiv. So kindly...
Can liquid helium is superfluidity state conduct heat infinitely fast?
I thought I have seen this is a paper somewhere a long time ago, but now I am not sure about that.
Hi all,
I'm not certain if this is the correct section of the forum for this thread but I'm trying to understand ghosts and BRST symmetry and my starting point is chapter 16 of Peskin and Schroeder where I've found a nagging issue. My issue is regarding the derivation of equation (16.6) on...
Homework Statement
Can someone explain to me what particles (fermions, scalar/vector bosons, gravitons, ...) can have their vacuum expectation values and why? Which components of these fields can have VEV-s?
The Attempt at a Solution
I am assuming only scalar boson fields have it (like Higgs...
I am currently reading this notes by t'Hooft, and I realized that a soliton and a Goldstone boson behave in a similar way: Both of them interpolate between the vacua. Keeping in mind Soliton is described classically in the notes(atleast until first few sections in chap1), Is there a relation...
I've never been able to get my head around the idea that forces are particles. In the case of fermions, a particle seems to be a natural concept. Even though it's really a wave, or an excitation in a quantum field, I can envision it as being something in a particular place. For bosons that...
Hi. I'm a retired software engineer who has always been fascinated in science. I was a math major in college, before the time that computer science majors were a thing. My key areas of interest these days are particle physics and quantum mechanics.
I'll be asking some questions that have...
Bosons are described as force carrier particles and, as I understand it, the Higgs mechanism explains why photons are massless, just as all the carriers of the strong nuclear force, the gluons, whereas the weak force bosons have mass. A peculiar type of field is postulated, the ‘Higgs field’. It...
The (residual) strong force between nucleons can be desribed as
- The exchange of a meson (from a nucleon to the other), as in picture b)
- The exchange of a quark and an antiquark: in picture a) one nucleon "gives" a quark and receive an antiquark and it's the opposite for the other
I do...
< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown >
Question:
An experiment is proposed to directly measure the width (Γ) and mass (m_H) of the Higgs boson via the reaction: muon+ + muon- > H.
Sketch a graph of the expected cross section as a...
Is this true?:
During beta decay a quarks' spin is changed and the mass/ energy difference is converted to a W boson which quickly decays into an electron/positron and an anti neutrino/neutrino. The mass/ energy is conserved through E=mc^2.
Mesons and baryons have both a ground state and excited states involving the same valence quarks but a higher mass (which can in principle be calculated from QCD).
Fundamental fermions and bosons, however, do not appear to display this behavior. They have a ground state, and while there are...
In school we learn that mass is made of the amount of particles within an object!.
but then we have found something called higgs boson and boson field which is said to be responsible for an object mass. I have read how higgs boson and boson field work but I still don't understand how the higgs...
Scalar glueballs in QCD appear as a result of violation of global conformal (scale) symmetry - the energy-momentum tensor has a nonzero trace. According to the Goldstone theorem, this (violation of global symmetry) corresponds to the appearance of scalar massless bosons.
Why, then, are the...
Hello,
I have read somewhere that the Higgs Boson particle (or field) is responsible for the inflation of the universe. Does anybody have more information?
Thanks.
Boson stars seem to be a good fit for Dark Matter.
https://arxiv.org/pdf/1704.05057v1.pdf
Can you help me understand why such a huge particle with such low mass can exist, and how it could be found experimentally.
Does the Higgs field give mass to particles unrelated to it? All particles with mass or some particles?
Does the Higgs boson as such play a role in giving mass to other particles, or is the boson just a feature (excitation?) of the Higgs field?
Can the Higgs boson be reasonably described as a...
Can a W Boson convert an up quark into a down quark of the same generation? Where can I find a resource to understand what all the possibilities are for an up quark converting into other quarks of same or other generations?