Public Lecture-ANTIMATTER: What is it and where did it go?

Lecture Date: Tuesday, October 28, 2008. In this public lecture we will explore the mystery of antimatter: Where did it go? Why is the universe made up of only matter, with no observable antimatter? And why does the universe have any matter left in it anyway? The SLAC "B"-Factory was built to answer these questions. Over the last decade, almost a billion "B"-mesons were created and studied at the B-Factory to search for subtle differences between matter and antimatter, differences that lie at the heart of the antimatter mystery. We will explain the matter-antimatter discoveries made at the B-Factory, and their connection to this year's Nobel prize in physics. It does not matter if you have no prior knowledge of Antimatter; just bring your curiosity. Lecturer: Dr. Aaron Roodman, Stanford University.

[@mikeydflyingtoaster]

It always amazes me that people put the effort into producing these videos for the general public. The speaker in this video makes the topic extremely clear... as clear as it can be! Thank you so much for uploading this.

[@dabeast6861]

First of all (before my slightly cheeky comment!) allow me to thank you for posting these incredible public lectures. This lecture in particular i found truly fascinating and the lecturer did an incredible job of explaining antimatter to the layman. Now for my cheeky comment: You folks at SLAC can perform some of the most advanced engineering on the planet with your particle accelerators but you struggle to record audio without distortion! Buy a decent mic and a limiter guys, its not rocket science... or particle science for that matter!

[@cosmosphysics]

Such a nice and awesome talk

[@purplepick5388]

A mind blowing lecture ! thanx :)

[@hd-fractals]

such an awesome talk! thank you so much for this :)

[@artes.impias]

Great lecture, thank you !

[@MrTweetyhack]

"annihilate" here means it breaks up into particles which does not mean annihilate.

[@murthybn853]

awesome speech

[@VeggyZ]

I suppose I don't have the education needed so I don't understand the implications of a lot of this but .. I still find it very interesting, thanks for uploading this lecture.

[@Aluminata]

Would a collision between a single proton of matter / antimatter be observable?

[@SeanMauer]

56:00 "Abstract Charges"? ...How about different changes in the characteristics of space.

[@koomkevxav]

anti proton should be the next big thing on the black-market...

[@MrKmanthie]

why? You can't get high on it; you can't really make money on it & even if there was any usefulness for a black market to exist for "antiprotons", there'd be a hell of time in trying to keep any one of them from annihilation by, say, touching a side of whatever container would contain it. I'm sure you're being sardonic here so the logistics really don't matter. So, never mind.

[@hiteshsingh7215]

I am a Scientist of physics I am able for uses of antimatter for humanity because antimatter have large amount of energy but I am belongs to poor family.antimatter is very useful for all human beings.

[@MrKorrazonCold]

Antimatter formed by inward spherical wave fronts from the universe forms + charge (like dropping pebbles into a pond) Inward spherical wave fronts generate heat by multiplying electrical potential along cubic dynameters compressing the wave amplitude now the shorter the expanding transverse waves dividing gravity from its source Energy 4pi compression +1=mass.decompressing a constant C2 forming an inward force called gravity from plains of zero curvature wave front by wave front as time unfolds

[@konman001]

Next lecture should be titled: The Animatter matter - does it matter?

[@BartAlder]

The assumption there is no antimatter possibly breaks down at the galactic scale. He says there is no evidence of bulk annihilation in our own galaxy but that is not correct at all. There is just such a thing observed: it has been known for some time that there is a 511 keV emission line located around the galactic centre of the MW galaxy, with Sgr A* at its dead centre. This emission line extends to cover the whole galactic bulge. That is not a lack of any evidence for antimatter, it is an omission of the evidence which there is for bulk annihilation taking place and the existence of bulk antimatter inside our own galaxy. Also note that all spiral forms appear to have antisymmetric distributions of stars, so if in a region centred on some point (x,y,z) there is a given star density which you can estimate, you will find that same estimated star density reappears at the point in space (-x,-y,-z). This antisymmetry rule of spirals is genuinely weird to the extent that it is pretty much inexplicable if everything is only made of matter. If half the stars are antistars though... the antisymmetry makes a lot more sense and you can get rid of all the dark matter too.

[@MEDINAHSHRINER]

Then where does the bulk annihilation go? Then where do you get rid of the dark matter too? Who is to say it is dark and just a dimension we can not yet comprehend?

[@pmkeith]

Do anti particles gain their mass by interacting with anti Higgs particles?

[@magicsqr3414]

I don't expect to get an answer from the lecturer but.. at the Q & A, first question, your answer was basically that you look to see what it is not and then infer what it is, seems to me this is bordering on parapsychology. Just my opinion, please feel free to disregard it ;)

[@MrKmanthie]

MagicSqr ha ha ha...no, that is far from "parapsychology" which is pure bullshit. The way, for instance, the HIggs was "discovered" was that, when the 2 protons that had been boosted up to an acceleration of 99.99997 (give or take a .9) and they then smashed together, the result was a shower of new particles (e.g., ones that didn't appear until the collision). But, the thing is, those particles which arise out of the collision (including the HIggs Boson) decay probably 10 times or more between the blink of an eye, but the detector which is capturing this collision & the streams of particles to come out of that shower for a picosecond or at most, a microsecond before they decay are analysed by ATLAS or CMS (the 2 detectors at CERN) and the detector basically works backwards, starting with the decaying of the various particles & tracing their paths back, along their shots out from the collision; I know this is kind of a simplified explanation but it's a pretty good one for anyone who thinks there's anything "paranormal" going on! So, anyway, by tracing the trails and the angles at which these trails go, they're able to figure out which particle came out of the original collision; each one has a unique "signature". This is how the Higgs Boson was "found". Its unique "signature" was detected by ATLAS & since it was unique to what was expected of the Higgs, it was perfectly logical to infer that it was, indeed, the long-sought-after Higgs.

[@michaeloboyle8798]

I really liked this lecture and upvoted it but, please notice that you are smacking your lips while talking fairly often and it is very distracting. I am not trying to be mean but help. This talk was delivered over 8 years ago I understand and everybody changes and maybe you noticed it as soon as you watched this video. Sorry to be such a critic, but all of the material was very informative and thank you for the talk.