Why is there something rather than nothing? Well the answer may be found in the weakest particle in the universe: the neutrino. For over half a century Fermilab has been the premier particle accelerator facility of the United States and we got to visit with Don Lincoln to explore it’s science and its engineering. These days many of the super-powered geniuses of Fermilab are tackling the mysteries of the neutrino. Why? Because this elusive particle may hold powerful secrets: from the unification of the forces of nature to the biggest question of all: why is there something rather than nothing?

Black holes are awesome - but how about black holes being captured by the screaming vortex of a quasar, where they merge and grow like some monstrous version of a solar system. This insane hypothesis is getting closer to reality, according to the papers in today’s space time journal club.

The three body problem is famous for being impossible to solve. But actually it's been solved many times, and in ingenious ways. Some of those solutions are incredibly useful, and some are incredibly bizarre.

In particle physics we try to understand reality by looking for smaller and smaller building blocks. But what if that has been the wrong philosophy all along?

If the universe goes on forever, does that mean there are infinite versions of you out there?

What does the strong nuclear force, the fundamental symmetries of nature, and a laundry detergent have in common? They’re all important parts of the tale of the axion - a tale whose end may take us beyond the standard model and solve one of the most vexing mysteries in astrophysics.

It’s not surprising that the profound weirdness of the quantum world has inspired some outlandish explanations - nor that these have strayed into the realm of what we might call mysticism. One particularly pervasive notion is the idea that consciousness can directly influence quantum systems - and so influence reality. Today we’re going to see where this idea comes from, and whether quantum theory really supports it.

Why is it that we can see these multiple histories play out on the quantum scale, and why do lose sight of them on our macroscopic scale? Many physicists believe that the answer lies in a process known as quantum decoherence.

If we can’t ever peer into these other realities that are used to explain quantum mechanics, how do we know they exist? In order to understand what happens to those different branches, and to understand why we find ourselves in one of them, we need to embrace one of the interpretations of quantum mechanics.

In quantum world things are routinely in multiple states at once - what we call a “superposition” of states. But in the classical world of large scales, things are either this or that. The famous thought experiment is Schrodinger’s cat - in which a cat is in an opaque box with a vial of deadly poison that’s released on the radioactive decay of an atom. Quantum mechanics tells us that the atom’s wavefunction can be in a superposition of states - simultaneously decayed or not decayed. So is the cat’s wavefunction also in a superposition of both dead and alive.

If there’s one thing cooler than a black hole it’s a rotating black hole. Why? Because we can use them as futuristic power generators, galactic-scale bombs, and portals to other universes.

Normal maps are useless inside black holes. At the event horizon - the ultimate point of no return as you approach a black hole - time and space themselves change their character. We need new coordinate systems to trace paths into the black hole interior. But the maps we draw using those coordinates reveal something unexpected - they don’t simply end inside the black hole, but continue beyond. In these maps, black holes become wormholes, and new universes lie on the other side.

In astronomy we talk about billions of years like it’s no big deal. But how can we be sure about timescales so far beyond the capacity for human intuition? Our discovery of what we now call deep time is very recent - as recent as our discovery of the true spatial vastness of our universe. And it came as scientists tried to measure the age of the Earth. What they found was as shocking and humbling as anything seen through the telescope.

The Milky Way galaxy is relatively calm by the destructive standards of the rest of the Universe, and compared to its own very violent past. But just recently we discovered that its violent past was much more recent than we thought - and could even happen again.

From Stargate to Interstellar, wormholes are our favorite method for traveling across fictional universes. But they are also a very serious field of study for some of our greatest minds over the last century. So what’s the holdup? When do we get to wormhole ourselves out of here?

The universe is precisely 13.8 billion year old - or so our best scientific methods tell us. But how do you learn the age of the universe when there’s no trace left of its beginnings?

As the 19th century came to a close, physicists were feeling pretty satisfied with the state of their science. The great edifice of physical theory seemed complete. A few minor experiments remained to verify everything. Little did those physicists know that one of those experiments would bring the entire structure crashing down paving the way for the physics revolution of the 20th century.

This is a map of the multiverse. Or in physics-ese, it’s the maximally extended Penrose diagram of a Kerr spacetime. And in english: when you solve Einstein’s equations of general relativity for a rotating black hole, the universe does not come to an abrupt halt at the bottom of the gravitational pit. Instead, a path can be traced out again but you do not end up in the universe that you started in. Like I said, it’s a map of the multiverse.

It’s been 120 years since Henry Cavendish measured the gravitational constant with a pair of lead balls suspended by a wire. The fundamental nature of gravity still eludes our best minds - but those secrets may be revealed by turning back to the Cavendish experiment. That steampunk contraption may even reveal the existence of extra dimensions of space.

With the global pandemic of Covid 19 still encompassing the word, we are generally not big fans of viruses right now. But we sure are thinking about them a lot. That’s right, even astrophysicists are pondering these bizarre little critters. In fact, astrovirology, although very new, is actually an emerging subfield of astrobiology. And that’s because it turns out viruses don’t just influence organisms - they’re incredibly important on a planetary scale. Perhaps an interplanetary scale.

Conformal Cyclic Cosmology is a story of the origin and the end of our universe from great mathematical physicist Sir Roger Penrose. It’s goes like this: the infinitely far future, when the universe has expanded exponentially to to an unthinkably large size, and every black hole and particle has decayed into faint radiation .... that infinite stretch of space and time is identically the SAME THING as the infinitesimal and instantaneous big bang of a new universe, and our universe is just one in an endless chain.

Black holes are about the worst subjects for direct study in the universe. But at this stage, it’s all we can do to convince ourselves of their existence. Actually studying the physics of real black holes is much, much harder. I mean, we could try to make one - but that’s way beyond our current tech level, and also potentially humanity-destroying. Well it turns out we don’t need to make real black holes to at least get started with the lab work. We can instead study analog black holes - and by analog, I don’t mean old fashioned clockwork black holes - I mean analogies. Physical systems that aren’t black holes but that behave in similar ways - and may reveal the real behaviours of real black holes.

Black hole singularities break physics - fortunately, the universe seems to conspire to protect itself from their causality-destroying madness. At least, so says the cosmic censorship hypothesis. Only problem is many physicists think it might be wrong, and that naked singularities may exist after all.

The most precious substance in our universe is not gold, nor oil. It’s not even printer ink. It’s antimatter. But it’s worth every penny of it’s very high cost, because it may hold the answer to the question of why anything exists in our universe at all.

When we detected the very first gravitational wave, a new window was opened to the mysteries of the universe. We knew we’d see things previously thought impossible. And we just did - an object on the boundary between neutron stars and black holes, which promises to reveal the secrets of both.