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Ping George Herold: The Lyman-alpha transition for anti-hydrogen detected

Started by Unknown August 25, 2018
Laser breakthrough has physicists close to cooling down antimatter
 https://www.sciencedaily.com/releases/2018/08/180822131053.htm


hehe
:-)
On Saturday, August 25, 2018 at 5:27:37 AM UTC-4, 69883925...@nospam.org wrote:
> Laser breakthrough has physicists close to cooling down antimatter > https://www.sciencedaily.com/releases/2018/08/180822131053.htm
I have to admit I am not up to date on my anti-matter physics. The article says they will be performing spectroscopy and gravity measurements on the antihydrogen atoms. Would they expect to measure anything different from the same measurements on hydrogen? In fact, if they measure something different, won't that indicate a fundamental flaw in present theory? Or do they expect to see differences and I'm a long way from current? Rick C.
gnuarm.deletethisbit@gmail.com wrote:
> On Saturday, August 25, 2018 at 5:27:37 AM UTC-4, > 69883925...@nospam.org wrote: >> Laser breakthrough has physicists close to cooling down antimatter >> https://www.sciencedaily.com/releases/2018/08/180822131053.htm > > I have to admit I am not up to date on my anti-matter physics.
You don't know about the warp engines everyone's talking about?
> The article says they will be performing spectroscopy and gravity > measurements on the antihydrogen atoms. Would they expect to measure > anything different from the same measurements on hydrogen? In fact, > if they measure something different, won't that indicate a > fundamental flaw in present theory? > > Or do they expect to see differences and I'm a long way from current?
I don't think it's a matter (pun!) of expecting something. It's a matter of *hoping* to see something they don't expect.
In article <74b6b7eb-48b2-4e19-8a30-da6625eef134@googlegroups.com>,
 <gnuarm.deletethisbit@gmail.com> wrote:
>I have to admit I am not up to date on my anti-matter physics. The article says >they will be performing spectroscopy and gravity measurements on the antihydrogen >atoms. Would they expect to measure anything different from the same measurements >on hydrogen? In fact, if they measure something different, won't that indicate a >fundamental flaw in present theory? > >Or do they expect to see differences and I'm a long way from current?
That's very much the question... whether there are differences. One of the big unanswered questions in physics is why there is so little antimatter in the universe, compared to the amount of matter. The basic processes which create matter from energy (e.g. shortly after the Big Bang) are symmetrical, should create equal amounts of both... after which the matter and antimatter would tend to annihilate one another, leaving energy but no matter. In a fully symmetrical universe, we would simply not exist. There must be asymmetries in the physical processes involved, somehow, which favor the creation of matter over antimatter. This may or may not show up in measurable differences between matter particles and their antiparticles. Any such differences will (I think) require extending or changing the Standard Model... they will indicate that present theory is incomplete. Some such asymmetries have already been detected - violations of charge/parity symmetry in some particle decays. It's possible that direct measurements of antimatter particles may find others.
Dave Platt wrote:
> > One of the big unanswered questions in physics is why there is so > little antimatter in the universe, compared to the amount of matter. > The basic processes which create matter from energy (e.g. shortly > after the Big Bang) are symmetrical, should create equal amounts of > both... after which the matter and antimatter would tend to annihilate > one another, leaving energy but no matter. In a fully symmetrical > universe, we would simply not exist.
But what happened to the energy released when they annihilated each other? That would have been a lot of energy. What form did it take?
On 08/25/2018 10:05 AM, Tom Del Rosso wrote:
> Dave Platt wrote: >> >> One of the big unanswered questions in physics is why there is so >> little antimatter in the universe, compared to the amount of matter. >> The basic processes which create matter from energy (e.g. shortly >> after the Big Bang) are symmetrical, should create equal amounts of >> both... after which the matter and antimatter would tend to annihilate >> one another, leaving energy but no matter. In a fully symmetrical >> universe, we would simply not exist. > > But what happened to the energy released when they annihilated each > other? > > That would have been a lot of energy. What form did it take? > >
The Big Bang, more-or-less. Prior to about a picosecond after the Bang everything was in some kind fashion of grand-unified force quark-gluon plasma. After about a nanosecond all the forces had separated out into about the way we know them now, but the Universe was still too hot to allow hadrons to form and quark/antiquark plasma existed happily in thermal equilibrium. At a microsecond things have cooled enough for hadron/anti-hardrons to form, and they immediately start annihilating, releasing a huge amount of further energy but it's already way too late for it to heat things back up enough to "push the reaction back" to an earlier state, as it were. Much of that anti-matter is annihilated at one second, and matter/anti-matter proportion is basically at its current amount after one minute. After all that it took quite a while for the Universe to cool enough become transparent to radiation, basically glowing hot like the center of a thermonuclear fireball but for half a million years.
On Saturday, August 25, 2018 at 5:27:37 AM UTC-4, 69883925...@nospam.org wrote:
> Laser breakthrough has physicists close to cooling down antimatter > https://www.sciencedaily.com/releases/2018/08/180822131053.htm > > > hehe > :-)
That's cool. :^) Hanging on to anti matter is not so easy. I think it's certainly worth doing and getting the data. We expect the spectra to be the same, but who knows. Hydrogen is like the only element physics's can predict exactly with QM. And that's led to a bunch of nice physics. (One dream I have is to measure the Lamb shift in hydrogen, with today's diode lasers it's a piece of cake... well you have to make the hydrogen, that's the hard part.) George H.
On Sunday, August 26, 2018 at 3:30:55 AM UTC+10, George Herold wrote:
> On Saturday, August 25, 2018 at 5:27:37 AM UTC-4, 69883925...@nospam.org wrote: > > Laser breakthrough has physicists close to cooling down antimatter > > https://www.sciencedaily.com/releases/2018/08/180822131053.htm > > > > > > hehe > > :-) > > That's cool. :^) Hanging on to anti matter is not so easy. > I think it's certainly worth doing and getting the data. > We expect the spectra to be the same, but who knows. > Hydrogen is like the only element physics's can predict > exactly with QM. And that's led to a bunch of nice physics. > (One dream I have is to measure the Lamb shift in hydrogen, > with today's diode lasers it's a piece of cake... well you have > to make the hydrogen, that's the hard part.)
Hydrogen molecules are easy. A hydrogen atom source does seem to be commercially available. https://www.mbe-komponenten.de/products/mbe-components/gas-sources/habs.php It doesn't look cheap. -- Bill Sloman, Sydney
George Herold wrote
>On Saturday, August 25, 2018 at 5:27:37 AM UTC-4, 69883925...@nospam.org wrote: >> Laser breakthrough has physicists close to cooling down antimatter >> https://www.sciencedaily.com/releases/2018/08/180822131053.htm >> >> >> hehe >> :-) > >That's cool. :^) Hanging on to anti matter is not so easy. >I think it's certainly worth doing and getting the data. >We expect the spectra to be the same, but who knows. >Hydrogen is like the only element physics's can predict >exactly with QM. And that's led to a bunch of nice physics. >(One dream I have is to measure the Lamb shift in hydrogen, >with today's diode lasers it's a piece of cake... well you have >to make the hydrogen, that's the hard part.)
Electrolysis? My highschool physics teacher used electrolysis to make H and O gas, blew bubbles with it in soapy water that floated in the auditorium, had the kids ignite those with a lighter. You very fast learn that volume goes up exponentially with bubble size, the big ones gave a BIG bang, He was dangerous, I used to sit way back, but that was not safe either, he used the same H&O in a metal tube with a cork in it ignited by a spark plug, and shot a hole in the glass in the back of the place. Hey, just found this link in sci.astro: https://www.space.com/41573-black-holes-from-past-universes.html refers to paper: Apparent evidence for Hawking points in the CMB Sky Daniel An, Krzysztof A. Meissner, Roger Penrose (Submitted on 6 Aug 2018) https://arxiv.org/abs/1808.01740 Have not read it yet....
On Wednesday, August 29, 2018 at 2:55:21 AM UTC-4, 69883925...@nospam.org wrote:
> George Herold wrote > >On Saturday, August 25, 2018 at 5:27:37 AM UTC-4, 69883925...@nospam.org wrote: > >> Laser breakthrough has physicists close to cooling down antimatter > >> https://www.sciencedaily.com/releases/2018/08/180822131053.htm > >> > >> > >> hehe > >> :-) > > > >That's cool. :^) Hanging on to anti matter is not so easy. > >I think it's certainly worth doing and getting the data. > >We expect the spectra to be the same, but who knows. > >Hydrogen is like the only element physics's can predict > >exactly with QM. And that's led to a bunch of nice physics. > >(One dream I have is to measure the Lamb shift in hydrogen, > >with today's diode lasers it's a piece of cake... well you have > >to make the hydrogen, that's the hard part.) > > Electrolysis? > My highschool physics teacher used electrolysis to make H and O gas, > blew bubbles with it in soapy water that floated in the auditorium, > had the kids ignite those with a lighter. > You very fast learn that volume goes up exponentially with bubble size, > the big ones gave a BIG bang, > He was dangerous, I used to sit way back, but that was not safe either, > he used the same H&O in a metal tube with a cork in it ignited by a spark plug, > and shot a hole in the glass in the back of the place.
Yeah you need monatomic hydrogen. The usual way to make that is with a discharge in H2 gas. But single H is rather reactive and goes away, so you have to keep making it... I'm not really sure of the details.
> > Hey, just found this link in sci.astro: > https://www.space.com/41573-black-holes-from-past-universes.html > refers to paper: > Apparent evidence for Hawking points in the CMB Sky > Daniel An, Krzysztof A. Meissner, Roger Penrose > (Submitted on 6 Aug 2018) > https://arxiv.org/abs/1808.01740 > > Have not read it yet....
Me either :^).. maybe later. George h.