What Don’t We Get About Matter and Antimatter? We Shouldn’t Be Here.
Scientists work out methods for finding the difference between the magnetic moments of protons and antiprotons and see that they’re the same.
Why are we here, anyway? No, not in the what’s-the-meaning-of-it-all sense, but why haven’t matter and antimatter completely obliterated each other, the universe and us? In nature, two identical things that are 180° out of phase with each other — as matter and antimatter seem to be — cancel each other out. So, um, why are we here?
In audio, for example, two identical sound waves that are out of phase in this way produce silence:
So even if, say , you’re talking about identical recordings of something loud like a car horn, you get:
So we’ve got a problem with matter and antimatter not doing this, or rather, we should have a problem. Physics’ standard model says that when the universe came into being at the Big Bang, an equal amount of matter and antimatter was generated that should have — in our current understanding — wiped each other out, preventing the universe as we know it from forming.
Scientists have been thinking there must be something we haven’t come across yet that makes matter and antimatter not truly identical. A just-released study in the journal Nature reveals the frustrating outcome of a recent search for that difference at CERN. Christian Smorra, a physicist with their Baryon–Antibaryon Symmetry Experiment (BASE) collaboration, says, “An asymmetry must exist here somewhere but we simply do not understand where the difference is,” because, “All of our observations find a complete symmetry between matter and antimatter, which is why the universe should not actually exist.”
Previously, scientists have tried to find some difference other than polarity in matter and antimatter, measuring their mass and electric charge, and with a study last year of the properties of hydrogen and anti-hydrogen atoms: Nothing.
One aspect scientists haven’t been able to compare precisely before were the magnetic moments of the proton and antiproton — there’s been simply no way to do it. ( A magnetic moment is a measurement of an object's tendency to align with a magnetic field.) So ten years back, a team at BASE began trying to work out how they could.
BASE’s antiproton decelerator at CERN (STEFAN SELLNER, FUNDAMENTAL SYMMETRIES LABORATORY, RIKEN, JAPAN)
In 2014, BASE announced their first breakthrough: They could measure the magnetic moment of protons by trapping them in a magnetic field and inducing quantum jumps in the field’s spin using a separate magnetic field.
Tricky as that was, performing the same measurement in antiprotons was even thornier, since antiprotons are immediately destroyed when they come in contact with regular matter, such as one of the scientists’ containers.
The team figured out how to increase the the lifespan of antiprotons by holding them in an innovative, purpose-built iridium-sealed copper cylinder.
The chamber is said to look not unlike a Pringle’s can. (SELLNER, ET AL)
CERN describes the operation of the chamber, the most effective antimatter container ever made:
The reservoir trap is inside a cylinder with a volume of 1.2 litres. The particles are trapped by two overlying magnetic and electric fields, which keep the particles in a small volume in the centre of the trap. On one side of the trap there is a metal window, thin enough to allow the antiprotons to pass through but strong enough to ensure complete insulation from the outside. All the other sides of the trap are made from solid copper. The cylinder is then cooled to about 6 K (-267 °C) with liquid helium, so that an almost perfect vacuum is created.
A stream of antiprotons was fired into the frigid container on November 12, 2015, and the team was able to hold them there for an impressive 405 days.
During that time, they were able to run the magnetic moment measurement procedure they used for protons.
The new research documents the results of their efforts: the magnetic moment of an antiproton, out to nine places, is −2.7928473441 μN (μN is the symbol for micronewton force). And guess what? That’s identical to the magnetic moment of a proton. Could the difference lie somewhere beyond nine mathematical places?
Maybe, but, as Stefan Ulmer, leader of the BASE team avers, “This result is the culmination of many years of continuous research and development, and the successful completion of one of the most difficult measurements ever performed in a Penning trap instrument.”
So, for now, the puzzle continues, and scientists will keep sleuthing in hopes of solving this fundamental mystery : Why are we here?
Many believe that the internet has made it easier for us to participate in political activism. But is that really true?
- Protesting in person is costly in terms of money and resources; some people have children to take care of, jobs that can't be away from, or may not have time to attend a planning event.
- The internet was supposed to be a way to sidestep this barrier to political activism. But this doesn't consider the other barriers preventing poor and working-class folks from participating in digital activism.
- In particular, these people lack ASETs: access to computers, the skills to use them, the empowerment necessary to feel that using Twitter or other social media is for them, and the time to make use of digital platforms in an effective way.
Some games are just for fun, others are for thought provoking statements on life, the universe, and everything.
- Video games are often dismissed as fun distractions, but some of them dive into deep issues.
- Through their interactive play elements, these games approach big issues intelligently and leave you both entertained and enlightened.
- These five games are certainly not the only games that cover these topics or do so well, but are a great starting point for somebody who wants to play something thought provoking.
The bid to buy Greenland is unlikely to become seriously considered.
- Greenland and Danish officials alike think the idea is ridiculous.
- The island is an autonomous state, and it's unlikely the Danish would sell it because of yearly subsidies costs.
- After hearing the Danish Prime Minister call the idea absurd, Trump cancelled their forthcoming meeting.