News: "Scientists catch glimpse of a fifth force of nature". Article accuracy?

[edy]

I saw the following news article today and I'm trying to understand what is going on. Did they over-simply something, is it "news" or actually old stuff being rehashed on a slow news day, and what about some of the confusing descriptions they give in the article?

https://nationalpost.com/news/scientists-catch-glimpse-of-a-fifth-force-of-nature

For example, they start off talking about the four fundamental forces: gravity, electromagnetism, as well as strong and weak nuclear forces. As far as I knew, electromagnetism/strong/weak have been unified and the only force separate is gravity?

They also mention an experiment where they bombard Lithium-7 atoms with protons to get an unstable isotope of Beryllium-8. Then they say: "The beryllium-8 is supposed to transform into a positron and an electron, and as the energy of the light increases, the angle between the two particles should decrease and eventually separate completely."

I think what they meant to say was the Beryllium emits a positron and electron along with a photon (not that it transforms into those two particles), and that the energy of the photon is dependent on the angle those particles make to each other. Then the next quote confuses me:

"The Hungarian physicists observed the electron and positron separate at an angle of 140 degrees. It’s believed that at the moment the atom decays, the excess energy created a newly discovered unknown particle. Once that particle decayed, almost immediately, it then turned into a recognizable positron and electron."

So they are saying some transient particle is being emitted which then almost instantly decays into the respective electron/positron/photo? Is it that transient particle they are calling the "protophobic X boson"? And what does that have to do with "dark matter"?

Then a spelling mistake.... yes the article talks about the election... 

"The new boson is 17 megaelectronvolts, which is about 33 times the size of an election."   

I couldn't continue to read the article as I don't know how much they accurately translated for lay people to understand. Can anyone who has some physics knowledge filter through this and explain what they are talking about? Is it just typical science-news fodder?

[Sal Ammoniac]

Have you read the actual paper in Physical Review Letters? Science journalists often either make mistakes when interpreting papers in their articles, or purposely do things to make it easier for laypersons to read them.

[edy]

No I haven't. Thanks for suggesting it...  Here is the link and PDF, to save anyone else from looking for it in the news article:

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.071803

https://arxiv.org/pdf/1604.07411.pdf

I've attached the PDF if anyone is interested. I may have to brush up on the latest particle and quantum physics basics though to understand what this all means.

NOTE: I started reading the paper and after about the first page it gets to the point where I can't understand a thing. It gets too technical and presumes good familiarity with the topic. I'll have to wait for a Scientific American or some other lay-person publication that is at least better than National Post.

[iMo]

And here are the Hungarian scientists mentioned in the News:
https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.116.042501
https://arxiv.org/pdf/1910.10459.pdf

[edy]

There is also a more general article here on Wikipedia:

https://en.wikipedia.org/wiki/Fifth_force

It contains a lot of links and other background articles. I'm still not even sure what a "force" really is, although by the sounds of modern physics it is mediated by particles of some kind travelling from one bit of matter to another. If a force particle and a matter particle interact, what exactly is making them interact? Are they physically bouncing off each other, overlapping, combining, or is there a "force" they exchange? Do you get into a cyclic argument where you have to reduce things down further ad infinitum?

The main stumbling block here is understanding why at a fundamental level a force particle has an effect on some matter particles and not others, what makes force particles and why are they made, and do they exist if nothing is around them to detect them or be affected by them? For example, if a "force" is exerted between a proton and an electron, or between proton and proton, the mediating force particle is doing something to the other. One emits, the other receives? Or both emit? If they both emit, do they repel each other and why? I think I am just understanding the entire thing wrongly.

[rfeecs]

A nice article from the guy that does the Fermilab videos:
https://www.forbes.com/sites/drdonlincoln/2019/11/23/has-a-new-discovery-broken-known-physics/#674507a265be

Basically he says don't get too excited.  Wait for real independent confirmation.

[hamster_nz]

As per https://en.m.wikipedia.org/wiki/Electron_rest_mass the rest mass of an electron is 0.511 MeV.
.

So something 33x the mass would be -17MeV