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Physicists Investigate Why Matter and Antimatter Are Not Mirror Images (economist.com)
An anonymous reader shares a report: As mismatches go, it's a big one. When physicists bring the Standard Model of particle physics and Einstein's general theory of relativity together they get a clear prediction. In the very early universe, equal amounts of matter and antimatter should have come into being. Since the one famously annihilates the other, the result should be a universe full of radiation, but without the stars, planets and nebulae that make up galaxies. Yet stars, planets and nebulae do exist. The inference is that matter and antimatter are not quite as equal and opposite as the models predict.
This problem has troubled physics for the past half-century, but it may now be approaching resolution. At CERN, a particle-physics laboratory near Geneva, three teams of researchers are applying different methods to answer the same question: does antimatter fall down, or up? Relativity predicts "down", just like matter. If it falls up, that could hint at a difference between the two that allowed a matter-dominated universe to form.
This problem has troubled physics for the past half-century, but it may now be approaching resolution. At CERN, a particle-physics laboratory near Geneva, three teams of researchers are applying different methods to answer the same question: does antimatter fall down, or up? Relativity predicts "down", just like matter. If it falls up, that could hint at a difference between the two that allowed a matter-dominated universe to form.
Couldn't this be a case of a butterfly flapped its wings billions and billions of years ago, and now we have more matter than anti-matter?
Various ways of creating antimatter have been used in physics. One is to get a photon (particle of light) to convert into an electron and positron (antimatter equivalent of an electron). Another is to smash a proton into a necleus and create various particles of matter and antimatter and filter them by charge and momentum. If you want learn about antimatter in general, Don Lincoln has some introductory videos on YouTube.
falls down.
This problem has troubled physics for the past half-century...
This "problem" is why we are here. How about not calling the existence of the universe a "problem"?
Different kind of problem. (from Google):
Physics : Mathematics
- an inquiry starting from given conditions to investigate or demonstrate a fact, result, or law.
It must have been something you assimilated. . . .
What's wrong with asking how the universe works?
There is a retired scientist called Jean-Pierre Petit that has some ideas about this question (spoil: this antimater will fall down). This is the Janus cosmological model
. I do not know if he is right or wrong, but the videos are worth a look
“In the beginning the Universe was created. This had made many people very angry and has been widely regarded as a bad move.” Douglas Adams, The Restaurant at the End of the Universe
Inheritance is the sincerest form of nepotism.
Trust and Antitrust aren't mirror images either. No one's worried about that. :-)
It must have been something you assimilated. . . .
Very, very carefully.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Is that also the part of the story that makes sense?
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
The goatee that antimatter seems to have of course its not an exact mirror image
Your'e all thinking it, I just said it for you
Very, very carefully.
If all the antimatter ever made by humans were annihilated at once, the energy produced would be just about enough to make a cup of tea.
General relativity is based on the premise that there is no difference between gravity and acceleration, that is, gravitational mass is always exactly equal to inertial mass. If antimatter falls up, the whole theory collapses.
If antimatter repels ordinary matter but attracts itself, I suppose the universe would self-segregate into galaxy clusters made of one or the other. How sure are we that distant superclusters are made of the same stuff we are?
Well, perhaps not, but this would explain why this universe is "normal" matter with no "anti"-matter. In the gigantic virtual particle event that created this universe, there would of course need to be a paired "anti" universe where "normal" matter is scarce. Someday in the distant future the two will recombine and balance the books to zero sum... and then our universe will cease to be "The Ultimate free Lunch".
-- Insert witty one-liner here. --
CERN experiments to test the free-fall of antiatoms
https://cerncourier.com/does-a...
God uses Intel floating point numbers.
Table-ized A.I.
Similarly, the matter that we have in the universe today might just be the statistically insignificant leftover excess matter that happened to not get annihilated when approximately equal amounts of matter and antimatter were created.
File under 'M' for 'Manic ranting'
Anti-neutrons are definitely different from neutrons. Neutrons are made up of 3 quarks, two down and one up whereas anti-neutrons are made of three anti-quarks, two anti-down and one anti-up.
This is because neutrons are made of fermions which have different particle and antiparticle states. Only bosons, like the photon, have the same particle and antiparticle states.
This is almost duplicate since I remember a similar article which talked about some experiment by Italian scientists a few years ago.
But again, our current understanding is that gravity is the curvature of space and time. The anti-matter has no choice but to follow that curvature. It cannot pretend that curvature does not exist.
So, if anti-matter were actually fallen up you can throw general relativity out of the window. I do not expect that will happen.
Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
Couldn't this be a case of a butterfly flapped its wings...
Short answer: no, assuming you mean some random fluctuation in the early Universe. For the excess of matter over anti-matter in the early universe to be due to such a random fluctuation, there would have to be some process that allows more matter than anti-matter to be created and we have not seen anything that does this yet.
However, we have seen a bias between matter and antimatter in decays of certain types of particles made of quarks and anti-quarks bound together. While this is not enough to create more matter than anti-matter if the same effect exists in the oscillations of neutrinos then there may just be enough to explain the excess of matter over antimatter. However, this would still not be a random fluctuation but rather that the universe has an inbuilt bias in the laws of physics which favours matter over antimatter.
As an interesting aside this difference, called CP violation, is also the only physics we know of that requires three generations of quarks and leptons to exist. If there were only two generations we could not have a difference at least via this mechanism.
Can you explain us how do you create antimatter in this universe?
Smash things together with enough energy or, even simpler, find any nucleus which undergoes beta decay. The most common form of beta decay produces an electron and antineutrino (which is antimatter eventhough it will hardly ever interact) but there is also beta+ decay where a positron (antielectron) and neutrino are emitted.
The latter type is used by medical physicists in positron emission tomography. This can detect tumors too small to be seen any other way by using the two photons produced by the positron annihilating with an electron in your body to reconstruct where the molecules containing the decaying nucleus was in your body. It can also be used to study how drugs are absorbed.
If antimatter falls up, then matter would not dominate - rather, antimatter and matter would be segregated. Each galaxy (or perhaps cluster) would have one or the other dominate, in the sense that antimatter should be attracted to other antimatter. Though you ought to be able to tell if some galaxies/clusters are repelled by others and therefore already know this answer.
My money would be on "down", as "up" would also violate the equivalence between gravitational and inertial mass. Unless you're going to say antimatter repels other antimater. Hmm - that would mean antimatter never forms (anti-)stars and thus make it a candidate for "dark matter". That might have some merit after all...
What has happened to Slashdot?
Take off every 'sig' !!
Making a cup of tea from energy requires quite a lot of energy!
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
ampersand l t semicolon
ampersand g t semicolon
http://michaelsmith.id.au
That sounds very improbable.
http://michaelsmith.id.au
Very, very carefully.
If all the antimatter ever made by humans were annihilated at once, the energy produced would be just about enough to make a cup of tea.
Or, at the very least, something almost, but not quite entirely unlike tea.
It must have been something you assimilated. . . .
Behind a lot of borated polythene and lead.
Take a small sample of water containing Oxygen-18, irradiate it with a beam of 19MeV protons and some of the Oxygen-18 will be converted to Fluorine-18. When the Fluorine-18 atoms decay they release an anti-electron.
The polythene slows down the neutrons which are released when other atoms are hit by the 19MeV proton beam, the boron absorbs the neutrons, and the lead absorbs the huge gamma radiation dose produced by bremsstrahlung when the high energy protons hit the beam stop (usually a chunk of water cooled metal).
So if you've got a few million quid you can produce anti-matter. (been there, done that).
Maybe it is the effect of the two Lazarus' trapped in the negative magnetic corridor trying to escape?
(Or is the plural of Lazerus, Lazeri?)
Tracy Johnson
Old fashioned text games hosted below:
http://empire.openmpe.com/
BT
Nope, the "big U" Universe is always the ultimate free lunch.
Strange things are afoot at the Circle-K.
First method: Create isotopes that have a decay mode that emits anti-matter (usually in the form of positrons). This is a tried-and-true method and is already being used in industrial applications of anti-matter.
Second method: Smash particles together with enough oomph. Some anti-matter will be generated. Capture and isolate it.
World's most expensive tea for sure.
This "problem" is why we are here. How about not calling the existence of the universe a "problem"?
This problem led to Trump running America. We need to understand it so we can make sure the next universe doesn't end up in the same self destructive path after Spaceforce uses North Korean nukes to hit the reset button.