In a Universe Made of Antimatter, Does Love Still Exist?

The question of antimatter is a specter haunting the field of physics: Why is there more matter in the universe than anti-matter? Lawrence Krauss gives a surprising answer.

Lawrence Krauss: Most people don’t wake up in the morning and ask themselves the question, "Why do I live in a universe of matter?" But they should because if you think about it from the point of view of fundamental physics, matter and antimatter are almost exactly the same things. For every particle in nature there’s a particle that has equal mass and opposite charge. Antimatter only seems strange as I often like to say in the sense that Belgians seems strange. Namely Belgians aren’t intrinsically strange, but if you go into a large auditorium as I’ve often done and said how many Belgians are there? You rarely see them. Antimatter seems strange because we rarely see it. Why? Because hardly any of it exists in the universe. But if the universe were made of antimatter, it would look exactly the same. Antilovers could sit in anticars under an antimoon and make antilove and everything would seem exactly the same. So why do we live in a universe that has only matter and no antimatter? That’s one of the biggest mysteries in fact that’s been driving particle physics and cosmology over the last 40 years. If you started with a sensible universe it should have equal amounts of matter and antimatter. How would you end up with a universe in which for every particle of antimatter there may be more than 10 billion particles of matter? These are questions we have ideas about how to answer, but we don’t yet know exactly how to answer.

And that’s one of the reasons why we’re looking out in the universe to confirm, in fact, the processes that might create matter instead of antimatter and to look for sources of antimatter in the universe. It turns out that there are energetic processes involved. There’s black holes, including the black hole at the center of our galaxy, that are producing lots of antimatter. We don’t quite understand all of those processes. Some of them may be involved with exotic stuff like dark matter. Some of it may be involved with more pedestrian things like pulsars and energetic magnetic fields around stars. We don’t know all of the processes and that’s why we have to keep looking. And we have new tools, new windows on the universe like the Fermi telescope, which looks out in space at high-energy gamma rays and high-energy particles that are coming in that many of which don’t reach the Earth because of the atmosphere or magnetic fields around the Earth. Each new window we have on the universe surprises us and we may be surprised about the sources of antimatter are in nature. And some of those sources may help us understand that remarkable mystery of why we live in a universe full of matter.

 

The question of antimatter is a specter haunting the field of physics: Why is there more matter in the universe than anti-matter? Lawrence Krauss supplies an answer that, besides explaining what antimatter is, sheds light on why the question is so puzzling in the first place. Antimatter, speaking from the perspective of physics, is not a terribly strange thing. In fact, we would expect to see more of it — to balance the amount of regular matter in the universe.

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A Mercury-bound spacecraft's noisy flyby of our home planet.

Image source: sdecoret on Shutterstock/ESA/Big Think
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  • There is no sound in space, but if there was, this is what it might sound like passing by Earth.
  • A spacecraft bound for Mercury recorded data while swinging around our planet, and that data was converted into sound.
  • Yes, in space no one can hear you scream, but this is still some chill stuff.

First off, let's be clear what we mean by "hear" here. (Here, here!)

Sound, as we know it, requires air. What our ears capture is actually oscillating waves of fluctuating air pressure. Cilia, fibers in our ears, respond to these fluctuations by firing off corresponding clusters of tones at different pitches to our brains. This is what we perceive as sound.

All of which is to say, sound requires air, and space is notoriously void of that. So, in terms of human-perceivable sound, it's silent out there. Nonetheless, there can be cyclical events in space — such as oscillating values in streams of captured data — that can be mapped to pitches, and thus made audible.

BepiColombo

Image source: European Space Agency

The European Space Agency's BepiColombo spacecraft took off from Kourou, French Guyana on October 20, 2019, on its way to Mercury. To reduce its speed for the proper trajectory to Mercury, BepiColombo executed a "gravity-assist flyby," slinging itself around the Earth before leaving home. Over the course of its 34-minute flyby, its two data recorders captured five data sets that Italy's National Institute for Astrophysics (INAF) enhanced and converted into sound waves.

Into and out of Earth's shadow

In April, BepiColombo began its closest approach to Earth, ranging from 256,393 kilometers (159,315 miles) to 129,488 kilometers (80,460 miles) away. The audio above starts as BepiColombo begins to sneak into the Earth's shadow facing away from the sun.

The data was captured by BepiColombo's Italian Spring Accelerometer (ISA) instrument. Says Carmelo Magnafico of the ISA team, "When the spacecraft enters the shadow and the force of the Sun disappears, we can hear a slight vibration. The solar panels, previously flexed by the Sun, then find a new balance. Upon exiting the shadow, we can hear the effect again."

In addition to making for some cool sounds, the phenomenon allowed the ISA team to confirm just how sensitive their instrument is. "This is an extraordinary situation," says Carmelo. "Since we started the cruise, we have only been in direct sunshine, so we did not have the possibility to check effectively whether our instrument is measuring the variations of the force of the sunlight."

When the craft arrives at Mercury, the ISA will be tasked with studying the planets gravity.

Magentosphere melody

The second clip is derived from data captured by BepiColombo's MPO-MAG magnetometer, AKA MERMAG, as the craft traveled through Earth's magnetosphere, the area surrounding the planet that's determined by the its magnetic field.

BepiColombo eventually entered the hellish mangentosheath, the region battered by cosmic plasma from the sun before the craft passed into the relatively peaceful magentopause that marks the transition between the magnetosphere and Earth's own magnetic field.

MERMAG will map Mercury's magnetosphere, as well as the magnetic state of the planet's interior. As a secondary objective, it will assess the interaction of the solar wind, Mercury's magnetic field, and the planet, analyzing the dynamics of the magnetosphere and its interaction with Mercury.

Recording session over, BepiColombo is now slipping through space silently with its arrival at Mercury planned for 2025.

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