accelerator physics

Washington State University Physicists create 'negative mass'

Washington State University physicists have created a fluid with negative mass, which is exactly what it sounds like. Push it, and unlike every physical object in the world we know, it doesn’t accelerate in the direction it was pushed. It accelerates backwards.

The phenomenon is rarely created in laboratory conditions and can be used to explore some of the more challenging concepts of the cosmos, said Michael Forbes, a WSU assistant professor of physics and astronomy and an affiliate assistant professor at the University of Washington. The research appears today in the journal Physical Review Letters, where it is featured as an “Editor’s Suggestion.”

Hypothetically, matter can have negative mass in the same sense that an electric charge can be either negative or positive. People rarely think in these terms, and our everyday world sees only the positive aspects of Isaac Newton’s Second Law of Motion, in which a force is equal to the mass of an object times its acceleration, or F=ma. In other words, if you push an object, it will accelerate in the direction you’re pushing it. Mass will accelerate in the direction of the force.

Keep reading


Ask Ethan: Does Dark Energy Mean We’re Losing Information About The Universe?

“The universe’s expansion means our visible horizon is retreating; things faraway are vanishing continuously. (Albeit slowly, right now.) This would seem to imply we are losing information about the universe. So why is it the idea of losing information in a black hole’s event horizon is so controversial, if we’re constantly losing information to another horizon?”

As you look to greater and greater distances, you’re looking back in time in the Universe. But thanks to dark energy, what we can see and access today isn’t always going to be accessible. As galaxies grow more distant with the accelerated expansion of the Universe, they eventually recede faster than the speed of light. At present, 97% of the galaxies in the Universe aren’t reachable by us, even at the speed of light. But that isn’t the same as losing information. As a galaxy crosses over the horizon, its information never disappears from the Universe connected to us entirely. Instead, it gets imprinted on the cosmic horizon, the same way that information falling into a black hole gets imprinted on its event horizon. But there’s a fundamental difference between a black hole’s decaying horizon to the cosmic horizon’s eternal persistence, and that makes all the difference.

Come learn why even with dark energy, we don’t lose information about the Universe, but why the black hole information paradox is real!

Physics Lesson 1: Introduction

“It should be possible to explain the laws of physics to a barmaid.”

-Albert Einstein

In our society today, physics is made out to be an incredibly complex and nigh-impossible to understand. Although this may be true to some of the finer subjects in physics, it certainly isn’t the case for the wide variety of physics subjects. Through this series of lessons, I hope you’ll learn something about just how awe-inspiring physics can be. 

So where to begin? Well, in order to understand physics in its modern state, I believe you must first understand its history.

[Side Note: If you have any questions about what I talk about here, Or if you see anything that is incorrect- please let me know!] gives us a good general definition for physics: “the science that deals with matter, energy, motion, and force.” However, this is only a partial definition. To gain the full definition-n you Physics originated in ancient Greece when philosophers such as Thales of Miletus (who first conceived the idea that everything we see has a natural cause) and later Leucippus (who developed the first theory of atomism- the idea that everything is made up of atoms). Then, physics was simply known as a facet of philosophy focused on applying mathematics to our visible reality.

Around the same time, similar advancements would be made in India, China, and the middle east. Some Muslim philosophers and astronomers were so advanced that they continued to be used (once they were translated into Latin from Arabic) all the way into the 1600s.

In the 15th through 17th centuries, a scientific revolution started in Europe, sprouting such as Thomas Aquinas (who used motion as one of his five proofs for the existence of God) and Nicolaus Copernicus (the father of Heliocentricity). Here is where Physics gained its first name distinguishing itself from philosophy: Natural Philosophy- Considered by many to be the precursor to modern science.

Now, understanding this, we can give a more complete definition to use through this study: Physics is the Natural Science that involves the study of matter, its motion and behaviour through space and time, energy and force, as well as the philosophical study of nature and the physical universe.

But enough with the boring stuff! I can already hear you. Onto the interesting stuff!

Now, seeing as since physics (in its simplest form) is just the study of motion, we’ll be just looking over the basics of movement before I wrap this first lesson up (it’s already a bit lengthy, no?)

So, here are the laws that (pretty much) cover all movement in the universe. You might recognise them…

I. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.

(The ball don’t move ‘till you kick it.)

II.  The relationship between an object’s mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law, the direction of the force vector is the same as the direction of the acceleration vector.

(The ball will move differently if you kick it from another way- also it  accelerates more the harder you kick it.)

III.  For every action, there is an equal and opposite reaction.

(When you kick the wall, the wall kicks back.)

Now there are plenty of other factors that play into motion, such as velocity, time, acceleration, and perspective to name a few, but they’ll be discussed in detail in my next lesson which will again brush the concepts of motion (specifically perspective). However the next few lessons will focus more heavily on gravity, energy, and magnetism as in my experience people generally like to learn about things blowing up instead of just plain movement.

Again, if you have any questions, corrections, requests for future content, or if you just want to talk, please feel free to send me an ask or a message!

Thanks for reading :)


If you put that ball on that machine while it wasn’t spinning, it would just roll straight down the lower sides. 

The raised edges would keep it in the middle line, but it’s only controlled in one direction. By spinning it, you constantly alternate the position of the tall sides, meaning that the ball is held in the middle, never able to fall off.

Particle accelerators control particles in the same way. Magnetic or electric fields can only direct particles in one plane at a time, so to keep a beam of particles rushing down a particle accelerator in one focused stream, the current gradient must constantly oscillate. This means the particles are constantly held in place, never able to shoot off in one direction.

Here’s the same principle in action: these are tiny pollen grains being held in place by an oscillating field. Rods in the four corners of the beam establish a field that oscillates many times a second to keep the pollen trapped. If it didn’t constantly switch, the pollen would all fly off in one direction.

Watch the full film with Dr Suzie Sheehy for more.


5 Reasons Why The 21st Century Will Be The Best One Ever For Astrophysics

“There’s always a temptation to think that our best days are behind us, and that the most important and revolutionary discoveries have already been made. But if we want to comprehend the biggest questions of all — where our Universe comes from, what it’s truly made of, how it came to be, where it’s headed in the far future, how it will all end — we still have work to do. With unprecedented telescopes in size, range, and sensitivity set to come online, we’re poised to learn more that we’ve ever known before. There’s never a guarantee of victory, but every step we take brings us one step closer to our destination. No matter where that turns out to be, the journey continues to be breathtaking.”

What does the future of astrophysics look like? Have we already made all of the fundamental discoveries we’re going to make? Is the rest just categorization of objects, identification of more examples of what’s already known, and minor refinements of the knowledge we already have? Or are there fundamental discoveries still to come, just waiting for us to reveal them? There are so many big questions still out there, and a great many of them have astrophysical consequences! In addition to new observatories, larger telescopes than ever, and problems like dark matter and the matter/antimatter asymmetry, there are five recent discoveries – within the last generation – that have significant implications for the Universe.

Come take a look at five of them: neutrino mass, the accelerating universe, exoplanets, the Higgs boson, and gravitational waves, and learn what the future holds!

Giant Accelerator Ready to Restart in Search for Fundamental Laws of Nature

by Michael Keller

The world’s largest and most powerful atom smasher will be firing back up for a new round of experiments as early as this Thursday after being shut down for upgrades two years ago. 

When physicists throw the power switch, the overhauled Large Hadron Collider will send unimaginably tiny particles like protons and the nuclei of lead atoms in opposite directions with significantly more energy than when the experiment’s first run ended in early 2013. 

“We are really excited because we are entering a new phase of the LHC after two years of heavy maintenance and heavy improvement of the whole accelerator chain, of the whole infrastructure,” said Rolf-Dieter Heuer, a German particle physicist who heads CERN, the organization that runs the LHC. “And to restart the LHC now at a new, higher energy, which hopefully opens new windows–depending on the kindness of nature, of course–we are excited.”

See more images and learn more below.

Keep reading

Okay, I want everyone to take a moment to think about Mako and Ami as science class partners.

Now, Mako isn’t very school-smart most of the time, and I’d imagine most of the math and physics stuff goes right over her head. But chemistry? That’s a whole lot like cooking. And the plant side of biology clicks with her instantly.

Ami is mostly the reverse, math is second nature to her, and wanting to be a doctor means she’s had an ongoing interest in animal biology. She’s good at Mako’s strong points, too (and likely academically far better), but Mako brings something extra she can’t get from textbooks. They balance each other out perfectly.


How long has the Universe been accelerating?

“The Universe has been accelerating for the past six billion years, and if we had come along sooner than that, we might never have considered an option beyond the three possibilities our intuition would have led us to. Instead, we get to perceive and draw conclusions about the Universe exactly as it is, and that’s perhaps the greatest reward of all.”

One of the biggest surprises in our understanding of the Universe came at the end of the 20th century, when we discovered that the Universe wasn’t just expanding, but that the expansion was accelerating. That means the fate of our Universe is a cold, lonely and isolated one, but it’s a fate that we wouldn’t have uncovered if we were born when the Universe was just half its current age. By understanding the Universe’s expansion history and determining what the different components are that it’s made of, we can figure out exactly how long the Universe has been accelerating. We find that dark energy rose to prominence some 7.8 billion years ago, and the Universe has been accelerating for the last 6 billion years. As the acceleration continues, more and more galaxies become unreachable from our perspective, even at the speed of light; that number’s already up to 97% of the galaxies in our visible Universe.


On tonight’s episode of #Ponderlust, we go full quantum. That’s right, we’ll be talking about one of the most gargantuan structures humans have ever assembled – the Large Hadron Collider. 

In excitement for this, indulge in this science-gasmic Symphony of Science production all about the quantum world which underpin all of nature: particle physics! 

Wait, what?

The known universe is made up of 12 particles of matter (fermions - quarks, leptons, antiquarks, & antileptons - or matter/antimatter particles; bosons - gauge bosons & Higgs boson - or “force particles” that influence interactions between fermions) and 4 forces of nature (strong, weak, gravity, electromagnetism). The Large Hadron Collider (LHC) is essentially a research lab investigating where, why, when, and how those 12 particles and 4 forces came to be, and what that knowledge communicates to us about the life and death of the universe. 

Confusing? Fear not. Even the legendary physicist Richard Feynman stated 

I think I can safely say that nobody understands quantum mechanics.” 

Join us tonight at 8:30PM EST as we embark down the rabbit hole of particle acceleration and into a discussion of the Large Hadron Collider at CERN.

We want to hear from you too, so submit your #Ponderlust tagged questions, comments, or podcast suggestions and we’ll respond to them on the show!


Cosmic Rays May Reveal New Physics Just Out Of LHC’s Reach

“It has been known for several years that the muon signal seems too large compared to the electromagnetic signal; the balance between them is off. But the observations were not necessarily based on a very solid data footing because it was dependent on a total energy estimate, rather than a total energy measurement. If you don’t measure all particles of the shower and have to extrapolate from what you measure, there are some significant uncertainties that result.”

High-energy particles from space, generated from stars, white dwarfs, neutron stars, black holes, active galaxies and more, can far exceed the energies achievable by accelerators like the LHC. Even if you take into account the severe difference in available energy for producing new particles, cosmic rays still have the edge. But because there are so many interactions for them to undergo before they strike the ground, the signal gets incredibly messy. Preliminary detection results showed a discrepancy between what’s predicted – that a certain percent of the energy should be in photons vs. muons – and additional tests were deemed necessary. Now they’ve implemented a new method with the most advanced detector arrays, and the discrepancy is stronger than ever. Could this be the sign of new physics that particle physicists have been hoping for?

If it is, it’s the strongest motivation ever to build a new collider 10 times as energetic as the LHC, as it will finally take us beyond the Standard Model, experimentally!