When the Large Hadron Collider found the Higgs boson in 2012, it was the culmination of a decades-long worldwide hunt. The Nobel Prize-winning discovery of gravitational waves at the LIGO detector came a century after Einstein had predicted these phenomena. But even with multiple major breakthroughs in the past several years, there remain huge elusive discoveries in space and physics that are still out of scientists' reach.
Scientists at the LHC are plugging away at the frontiers of physics in search of , a way to fill in some of the gaps in the Standard Model of particle physics. This idea is a bit complex, but to boil it down: The model would seem to predict that particles don't have mass. And yet, we know they do. The Higgs Boson appears to answer part of this problem by giving mass to particles. But even so, things don't quite add up the way they're supposed to.
A simple explanation is to say that for each particle, there's a mirror particle. (This isn't quite like antimatter, which is a different idea.) The mirror particle would have a half-integer spin, or a sort of tilt to the way the particle moves that makes it similar but hard to detect—because we've never seen something like that before, and it may not exist in our day-to-day. These supersymmetric particles also would explain why the Higgs boson is relatively light: "The extra particles predicted by supersymmetry would cancel out the contributions to the Higgs mass from their Standard-Model partners, making a light Higgs boson possible," .
If we can figure out supersymmetry, then we can figure out why gravity is so weak. Put simply, there are four fundamental forces—electromagnetisim, the strong nuclear force that holds atoms together, the weak nuclear force that catalyzes radioactive decay, and gravity. Gravity is quite the weakling when compared to these forces—even though, by all accounts, they're all the same force acting in different ways. Supersymmetry takes the atoms we know and gives them a heavier cousin that could account for a whole lot of things, including this peculiar behavior. A companion to the Higgs field could also better explain why matter has more mass than it should by all accounts.
If physicists can detect supersymmetry, then it would help to answer many questions about why matter acts the way it does at higher energies, and means the Higgs field has less heavy lifting to do than what we've previously measured at the LHC.
The search for supersymmetry is just one part of a bigger problem: The standard model of physics doesn't work. Gravity doesn't behave like other related forces do, showing a lot more weakness than, say, the pull of electromagnetism. Neutrinos apparently have mass even though they shouldn't. Antimatter is mostly MIA. Particles behave weirdly at the smallest levels, and in complete disharmony at the biggest possible levels.
Every test seems to tell us that our is mostly right, but shouldn't be. It's an odd paradox and something that needs to be rectified in order to truly understand the universe. It's perhaps the biggest question in physics right now.
For our universe to expand at the rate we see it expanding, there needs to be a whole lot of matter and energy "pushing" at it. Yet all the matter we see is only about 4 percent of what's necessary to make the universe expand as it does. That leaves 68 percent of the universe to be made up of dark energy—the force expanding the universe—and 26 percent to dark matter, which, even though we can't see it and don't know what it's made of, gives us our understanding of how large objects like galaxies push and pull on one another.
There are two leading candidates for what constitutes dark matter: WIMPs and MACHOs. are Weakly Interacting Massive Particles, which would mean that dark matter is a kind of matter that passes right through electrons, protons, neutrons, etc., but still has a gravitational pull. , Massive Compact Halo Objects, refers to the idea that dark matter is an accumulation of giant objects we can't see because they don't give off light. This idea proposes that black holes, non-pulsing neutron stars, rogue planets, brown dwarfs, and other celestial oddities could add up to a lot of the matter out there.
We've yet to find good evidence in favor of either. The hunt is on.
We know the basic facts about how it all started. There was a Big Bang nearly 14 billion years ago, followed by rapid expansion and changes. A few hundred million years after that, the first galaxies formed. But exactly what happened during the time in between is shrouded in a fog of darkness.
We call this time just after the darkness the Epoch of Reionization. That's because the universe, prior to this, appeared like a thick cloud for a time before the galaxies "reionized" hydrogen into a transparent state. The James Webb Space Telescope (JWST), now slated to launch in 2019, will be able to peer near this era in search of what the first galaxies looked like and how their bursting into life cleared the universe for our modern day eyes, as well as possibly find what caused it to cloud over like it did.
Scientists spotted the first exoplanets in the 1990s, and since then they've turned up thousands more including a few dozen we know to be in the habitable zones around their stars. Still, we have no idea if any can support life. Many of these planets orbit small, active stars that could destroy an atmosphere, drastically cutting back the chances for life.
James Webb will be able to look at these candidates and determine if they have atmospheres and if certain elements are present. If so, it would mean a whole lot more of our universe is potentially friendly to life. Along with Webb, a NASA probe called Transiting Exoplanet Sky Survey (TESS) will look at planets around larger, more-Sun-like stars to find planets a lot more like Earth than discovered so far.
This seems far out to say, but there's never been a better time to find aliens. Webb could find habitable worlds. We could find life in our solar system on watery worlds. And the $100 million is listening for alien signals over a 10-year span. It's a better time than ever before to hunt for life out there.