Comments on: Helicity, Chirality, Mass, and the Higgs http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/ Thoughts on work and life from particle physicists from around the world. Tue, 06 Oct 2015 08:06:00 +0000 hourly 1 http://wordpress.org/?v=4.2.5 By: Kevin http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-1115787 Thu, 04 Dec 2014 19:58:00 +0000 http://www.quantumdiaries.org/?p=10783#comment-1115787 How many times per second does an electron at rest interact with the Higgs field? Is the interaction rate proportional to the rest mass of the particle? As a particle is accelerated does it interact less frequently from an inertial observer’s perspective? If so, is the change in interaction rate due just to time dialation or some other effect?

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By: Jakob http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-1115786 Thu, 04 Dec 2014 12:45:00 +0000 http://www.quantumdiaries.org/?p=10783#comment-1115786 Hi Flip, now with your changes your text has become impossible to understand because you change your names halfway trough. As pointed out by Ivan you start with defining the positron as right-chiral. This way you define the usual Dirac spinors as left-chiral electron and left-chiral anti-positron. In addition, you point out that the electron and the antipositron have the same charge and chirality. I think you noticed that this can’t be correct, because during propagation something left-chiral mixes with something right-chiral. With your definitions from the beginning this is impossible, because everything right-chiral has positive charge and therefore we would have a mixing of charge during propagation. Therefore you use a new definition after the “important summary”. Then, there you define the positron as left-chiral and we can have a mixing of the electron (=left-chiral) with the anti-positron (right-chiral) without violating charge conservation. Anyway, then it becomes unclear what we write conventionally into the Dirac spinor and call electron and positron. I’m pretty sure you’re aware of all this, but rewriting would mean drawing lots of pictures again. Nevertheless a short remark may be in order, because things are really confusing right now.

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By: Ivan http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-806562 Sat, 18 Oct 2014 18:57:03 +0000 http://www.quantumdiaries.org/?p=10783#comment-806562 You say here the positron has right-chiral: “Electrons (left-chiral) and positrons (right-chiral) are two completely different particles, as evidenced by the positron’s mustache.”
And you say here that it has left-chiral: “Positron: left-chiral, charge +1, cannot interact with the W”

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By: gary http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-203936 Thu, 29 May 2014 23:53:21 +0000 http://www.quantumdiaries.org/?p=10783#comment-203936 Excellent explanation . So my question now is what exactly is the empirical evidence for separating an electron into two chiralities…Is there experimental evidence that one chirality ‘interacts” with the W ? Or is there some other evidence?
Thanks.

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By: Colin http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-178488 Mon, 24 Mar 2014 17:18:44 +0000 http://www.quantumdiaries.org/?p=10783#comment-178488 You wrote: “There is no “rest frame” in which a massless particle is at rest. The analogy for this is driving on the freeway: if you are driving at the same speed as the car in the lane next to you, then it appears as if the car next to you is not moving (relative to you).”

I did a double-take on this paragraph, but I believe you simply switched from talking about massless particles (that you cannot catch up with) to massive particles (that you can).

I don’t believe I know a single fact about the weak force that isn’t weird.

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By: Walter http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-172432 Sun, 09 Feb 2014 15:10:37 +0000 http://www.quantumdiaries.org/?p=10783#comment-172432 No need to reply to my previous message, if indeed anyone was going to.
I realise it’s a complex issue and I am following up on it using other sources etc, so hopefully it will understand it eventually.

Walter

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By: Walter http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-172211 Fri, 07 Feb 2014 10:30:26 +0000 http://www.quantumdiaries.org/?p=10783#comment-172211 I just want to get it clear in my head what’s happening here!
The mixing that’s happening,it’s confusing to me,the naming

For example take the electron defined as the particle “as it is now”a mix between two quanta.
If it’s a mix, what actually are the two mixed particles, one can’t surely therefore be an electron as we NOW know it (as you suggest) which puts in doubt that the other particle is an anti-positron?
The properties of the mixed particle and each individual components that makes it up must also differ ?

I’ve been trying to get clarity on this since I doing a presentation on the Higgs and this part I can’t resolve, it’s almost if you don’t mind me saying, that your making it up ?

Walter

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By: Skyguy93 http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-162500 Thu, 05 Dec 2013 09:08:01 +0000 http://www.quantumdiaries.org/?p=10783#comment-162500 First of all, love this blog. I’m not a physics student, but I decided to try and understand the Higgs and the only thing I don’t understand is how is the “neutral Higs” different than “The Higgs”…it’s right chiral, as opposed to spinless? What then is the difference between H+ and H-? one of them got their weak charge from an electron and one of them got their weak charge from an anti-electron? But which is which?

Also, if I understand all of this correctly, when a fermion hits “the Higgs” the higs particle is converted into the H+ H- H0 bosoms which are then promptly asborbed by the weak force bosoms. And because of this there is really only one Higs ( the other three being unstable?)

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By: Quantum Diaries http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-161898 Mon, 02 Dec 2013 23:12:29 +0000 http://www.quantumdiaries.org/?p=10783#comment-161898 Hi Joseph,
A good place for reading more about the Higgs mechanism and how it relates to the mass of the fundamental particles would be this post:
http://www.quantumdiaries.org/2013/10/07/higgs-mechanism-for-electrical-engineers/
Or this post:
http://www.quantumdiaries.org/2012/03/02/all-on-the-higgs-for-nearly-everyone/

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By: Joseph http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-161833 Mon, 02 Dec 2013 16:16:32 +0000 http://www.quantumdiaries.org/?p=10783#comment-161833 Hi Flip,

I’m not sure where the best place is to post this question, but I thought here would be good. I’m wondering what the explanation is (if there is one) for how mass increases in terms of the Higgs mechanism. The mass of the leptons comes from how frequently they interact with particles from the Higgs condensate (is that correct?…). At speeds where relativity becomes relevant, mass increases, and so does that mean that at higher speeds it becomes more likely for a particle to interact with Higgs particles? Is the answer insightful in any way?

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By: Harry Johnston http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-144471 Tue, 03 Sep 2013 03:04:57 +0000 http://www.quantumdiaries.org/?p=10783#comment-144471 So … what is the chirality of the physical electron, at rest? It looks like it should be 0?

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By: Haibara http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-127256 Sun, 05 May 2013 14:34:39 +0000 http://www.quantumdiaries.org/?p=10783#comment-127256 Hi.why no helicity=0 for massless particle?

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By: henry-couannier http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-114665 Tue, 19 Mar 2013 10:49:13 +0000 http://www.quantumdiaries.org/?p=10783#comment-114665 Hello ,

The analogy of the chirality mixing mass term with another kind of mixing that takes place in the neutrino sector is interesting but raises a few questions for me:

Shouldnt we expect to be able to test (experimental evidence) a kind of disapearing effect if starting from a left chiral electron eigenstate of the weak interaction (emitted in a weak interaction for instance) then after some flight distance again a weak interaction only sensitive to the left chiral component of the mixing (mass mixing term due to propagation) should manifest giving only half of the interactions that would have resulted from an electron remaining pure left during its propagation. Is that the case?

Alternatively if the electron interacts electromagnetically is it possible to probe experimentally (for instance by studying the angular repartition of the tracks) wether the electron then interacted as a left or right chiral particle. The latter case would be an evidence for oscillation as for the neutrinos case.

In other words , is it possible to probe the existence of the chriral mixing term appart from the existence of mass itself? Does this question make sense at all?

best

F H-C

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By: Jesse http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-105880 Sat, 16 Feb 2013 10:09:14 +0000 http://www.quantumdiaries.org/?p=10783#comment-105880 and i more question: In electron pairing, electron up and down mean left and right helicity or left and right chirality?

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By: Jesse http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/#comment-105853 Sat, 16 Feb 2013 06:34:39 +0000 http://www.quantumdiaries.org/?p=10783#comment-105853 Hi Flip,

I want to clarify my doubt here. Isn’t the physicsl electron the combination of left helicity left chiral electron component and right helicity left chiral anti-positron component?

left helicity left chiral electron will have left helicity right chiral positron in mirror (CPT). while left helicity left chiral electron would have right helicity right chiral anti-electron projection in morror. In case of positron, left helicity right chiral would have right helicity left chiral anti-positron.

in this scenario, left helicity left chiral electron should combine with righthelicity left chiral anti-positron and right helicity left chiral electron should combine with left helicity left chiral anti-positron.

Please think on it and resolve this doubt. I’m totally perplexed you can imigine this in writing that i can’t even describe simply. many thanks!!

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