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Physicists Test Symmetry Principle With an Antimatter Beam
Hugh Pickens DOT Com writes "Jon Butterworth has an interesting article at The Guardian about the idea of standpoint-independence in physics and the absence of 'privileged observers.' The ASACUSA experiment at CERN plans to make a beam of antimatter, and measure the energy levels as the beam travels in a vacuum, away from the magnetic fields and away from any annihilating matter. The purpose of the experiment is to test CPT (Charge/Parity/Time) inversion to determine if the universe would look the same if we simultaneously swapped all matter for antimatter, left for right, and backwards in time for forwards in time. In string theory for example it is possible to violate this principle so the ASACUSA people plan to measure those antihydrogen energy levels very precisely. Any difference would mean a violation of CPT inversion symmetry. Physicist Ofer Lahav has some interesting observations in the article about how difficult it is these days for physicists to develop independent points of view on cosmology. 'Having been surrounded by a culture in which communication is seen as generally a good thing, this came as a surprise to me, but it is a very good point,' writes Butterworth. 'We gain confidence in the correctness of ideas if they are arrived at independently from different points of view.'
A good example is the independent, almost simultaneous development of quantum electrodynamics by Richard Feynman, Julian Schwinger and Sin-Itiro Tomonaga. They all three had very different approaches, and Tomonaga in particular was working in wartime Japan, completely cut off from the others. Yet Freeman Dyson was able to prove that the theories each had provided for the quantum behavior of electrons and photons were not only all equally good at describing nature, but were all mathematically equivalent — that is, the same physics, seen from different points of view. Whether we are using thought experiments, antimatter beams, sophisticated instrumentation, or sending spaceships to the outer solar system, Butterworth says the ability for scientists to loosen the constraints of our own point of view is hugely important. 'It is also, I think, closely related to the ability to put ourselves into the place of other people in society and to perceive ourselves as seen by them — to check our privilege, if you like. Imperfect and difficult, but a leap away from a childish self-centeredness and into adulthood.'"
A good example is the independent, almost simultaneous development of quantum electrodynamics by Richard Feynman, Julian Schwinger and Sin-Itiro Tomonaga. They all three had very different approaches, and Tomonaga in particular was working in wartime Japan, completely cut off from the others. Yet Freeman Dyson was able to prove that the theories each had provided for the quantum behavior of electrons and photons were not only all equally good at describing nature, but were all mathematically equivalent — that is, the same physics, seen from different points of view. Whether we are using thought experiments, antimatter beams, sophisticated instrumentation, or sending spaceships to the outer solar system, Butterworth says the ability for scientists to loosen the constraints of our own point of view is hugely important. 'It is also, I think, closely related to the ability to put ourselves into the place of other people in society and to perceive ourselves as seen by them — to check our privilege, if you like. Imperfect and difficult, but a leap away from a childish self-centeredness and into adulthood.'"
What's this icky nerd stuff doing on a political web site like Slashdot?
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
What I found most interesting is what the head researcher found interesting:
In other words: Cambridge (Hawking) Dogma
Cosmology has become a branding exercise for universities & their long research grant coat tails. It has been, in my view, hijacked by ideologically/branding driven pseudo-science that seeks to purvey an institutional view rather than reflect accurate science.
Stephen Hawking is a main offender. It's all about him being right that the universe does *not* end in heat death
Thank you Dave Raggett
The purpose of the experiment is to test CPT (Charge/Parity/Time) inversion to determine if the universe would look the same if we simultaneously swapped all matter for antimatter, left for right, and backwards in time for forwards in time.
Uh...last post, anyone?
Ezekiel 23:20
I don't like, actually. While I generally agree that a new orthodoxy is bad news in science and scientists shouldn't fear being shunned for putting forward new theories which go against that orthodoxy, I find it disturbing that the language of murky social engineering is finding its way into "scientific" commentary. The only people I've ever heard talk like that are those interested in equality of outcome, not of opportunity, which is pretty much the opposite of science.
At first I understood quantum mechanics well enough to get good grades on my problem sets and exams, but I regarded it as delusional because I was heavily into the deterministic Newtonian idea of The Clockwork Universe.
He was able to give me a deep insight into QM without ever once doing a derivation or even simple arithmetic. For the most part it was purely conceptual discussions of the two-slit experiment.
What convinced me of quantum indeterminism in the end was Feynman pointing out that the two-slit also works for electrons, not just photons, and that one can use Shot Noise to determine when individual electrons are leaving the hot wire filament used to produce them.
Even if you send over just one electron at a time, you still get the rippled interference pattern at the detector.
It turns out that an antiparticle going back in time is exactly the same as a regular particle going forward in time. Just by watching an individual particle, or only a few of them, you cannot determine which direction time is going on.
It's only when you have enough particles for their measure of entropy to make sense that you can determine which direction time is going in. Entropy ALWAYS increases with time, so if you watch a system of particles, and their entropy is steadily decreasing, they are going backwards.
I've never heard anyone mention it, but what about smaller systems of particles, where entropy can be measured, but whose entropy fluctuates? Does time go back and forth? I don't know.
"MAYBE THERE'S JUST ONE ELECTRON!" Feynman once shouted.
We don't think that's the case - that just one electron goes from the beginning of the Universe to the end, then returns as a positron - because if there were significant amounts of antimatter in the Universe, we would expect there to be lots of 0.511 MeV gamma rays in the cosmic radiation but there is not.
I am STILL stymied by a question he asked once:
"Why does a mirror reverse left-and-right but not up-and-down?"
Please mail me URLs of software employers.
> For instance, the belief that the world began in flames is a religious ideology that is thousands of years old, yet persists to this day veiled beneath the Big Bang theory.
Correlation does not imply causation.
I think you'd be surprised by just how much "religion" is actually just made up shit. There's now so many different deities and religions that you can point at almost any idea and say that it was predated by some religious type.
However, there is a whole world of difference between some nutter saying that the voices told him that the world began in fire and scientists proposing actual mechanisms and refutable experiments.
I do agree that cultural diversity is useful and important to scientific progress as approaching problems from different angles is a good thing and can often lead to breakthroughs.
You're a temporary arrangement of matter sliding towards oblivion in a cold, uncaring universe
I think you'd be surprised by just how much "religion" is actually just made up shit.
Let me take a stab at that: All of it?
The purpose of the experiment is to test CPT (Charge/Parity/Time) inversion to determine if the universe would look the same if we simultaneously swapped all matter for antimatter, left for right, and backwards in time for forwards in time.
"As long as no red flags are raised in the experiment, we plan to move forward with the project in November," said top engineer Fedwick McGillicutty. "Our hope is that, by reversing time itself, we can do away with the whole debacle that is 'daylight savings time.'"
Any sufficiently simple magic can be passed off as mere advanced technology.
Another "science" critic that doesn't understand what science is.
If you take a fuzzy creation story or prophecy you can make it fit anything you want. The myths that survive ARE the fuzzy ones that can be made to fit anything. It IS kind of like science actually: the scientific theories that survive are the ones that fit. Except science has the additional criteria that they have to also be as simple as possible and make specific predictions.
Your example defeats you nicely. Most scientists of the early 20th century (including Einstein and Eddington) had a strong belief in a basically static universe that was infinite in time, because that was the elegant solution with philosophical appeal. It took the indisputable evidence of the red shift to convince them that there was in fact a big bang which was the beginning of the current order, against their natural inclinations.
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