Category: quantum physics

Can We Test Gravitational Waves For Wave-Parti…

Can We Test Gravitational Waves For Wave-Particle Duality?

“Although we have every reason to believe that gravitational waves are simply the quantum analog of electromagnetic waves, we have, unlike the electromagnetic photon, not yet risen to the technological challenges of directly detecting the gravitational particle that’s the counterpart of gravitational waves: the graviton.

Theorists are still calculating the uniquely quantum effects that should arise and are working together with experimentalists to design tabletop tests of quantum gravity, all while gravitational wave astronomers puzzle over how a future-generation detector might some day reveal the quantum nature of these waves. Although we expect gravitational waves to exhibit wave-particle duality, until we detect it, we cannot know for certain. Here’s hoping that our curiosity compels us to invest in it, that nature cooperates, and that we find out the answer once and for all!”

One of the revolutionary discoveries of the quantum world was that every particle that we know of also behaves as a wave. Photons are the quanta associated with light, and every light wave is made up of a discrete number of photons. Particles like electrons also can behave as waves; if you send them through a double slit, even one-at-a-time, they’ll produce an interference pattern.

So what about gravitational waves? We’ve seen the wave part; could we ever test them for the “particle” part of that? Find out today!

This Is Why Two Higgs Bosons Don’t Have …

This Is Why Two Higgs Bosons Don’t Have The Same Mass As One Another

“In this quantum Universe, every particle will have properties that are inherently uncertain, as many of the measurable properties are changed by the act of measurement itself, even if you measure a property other than the one you wish to know. While we might talk about photon or electron uncertainties most commonly, some particles are also unstable, which means their lifetime is not pre-determined from the moment of their creation. For those classes of particles, their inherent energy, and therefore their mass, is inherently variable, too.

While we might be able to state the mass of the average unstable particle of a particular variety, like the Higgs boson or the top quark, each individual particle of that type will have its own, unique value. Quantum uncertainty can now be convincingly extended all the way to the rest energy of an unstable, fundamental particle. In a quantum Universe, even a property as basic as mass itself can never be set in stone.”

Create an electron, and there will be a certain set of properties that you’ll know for certain, irrespective of any quantum uncertainty. You’ll know its mass, its electric charge, its intrinsic angular momentum, and many other properties as well. But that’s because the electron itself is a fundamentally stable particle: it’s lifetime is infinite, with no uncertainty. This isn’t true for many of the particles of the Standard Model, though, with the heaviest particles like the Higgs boson, the W and Z bosons, and the top quark having the shortest lifetime. Well, there’s also an energy-time uncertainty relation, and that means that the shorter your lifetime is, the bigger your inherent uncertainty in your energy is. Now, combine that with the knowledge that E = mc^2, and what do you get? 

An inherently uncertain mass. Yes, it’s true: every top quark you create has a unique mass that’s different from every other top quark. Come find out the science behind this remarkable property of nature!

Yes, Virtual Particles Can Have Real, Observab…

Yes, Virtual Particles Can Have Real, Observable Effects

“Now that the effect of vacuum birefringence has been observed — and by association, the physical impact of the virtual particles in the quantum vacuum — we can attempt to confirm it even further with more precise quantitative measurements. The way to do that is to measure RX J1856.5-3754 in the X-rays, and measuring the polarization of X-ray light.

While we don’t have a space telescope capable of measuring X-ray polarization right now, one of them is in the works: the ESA’s Athena mission. Unlike the ~15% polarization observed by the VLT in the wavelengths it probes, X-rays should be fully polarized, displaying right around an 100% effect. Athena is currently slated for launch in 2028, and could deliver this confirmation for not just one but many neutron stars. It’s another victory for the unintuitive, but undeniably fascinating, quantum Universe.”

If you think about empty space at a quantum level, you’ll find that it isn’t so empty, after all. Due to the inherent effects of quantum uncertainty, particle/antiparticle pairs pop into and out of existence continuously, including electrically charged particles. If you look at the quantum vacuum in the presence of a strong enough external magnetic field, the positive and negative particles, even though they’re only virtual particles, will move differently, and therefore will affect the real particles that pass through them differently than if there were no magnetic field. This leads to a real, observable signal that can be seen in space: around neutron stars! 

Heisenberg first predicted this in 1936, and today, we know it’s true. Get the story of the first observable effect of vacuum birefringence today.

The Quantum Physics That Makes Fireworks Possi…

The Quantum Physics That Makes Fireworks Possible

“Fireworks might appear to be relatively simple explosive devices. Pack a charge into the bottom of a tube to lift the fireworks to the desired height, ignite a fuse of the proper length to reach the burst charge at the peak of its trajectory, explode the burst charge to distribute the stars at a high temperature, and then watch and listen to the show as the sound, light, and color washes over you.

Yet if we look a little deeper, we can understand how quantum physics underlies every single one of these reactions. Add a little bit extra — such as propulsion or fuel inside each star — and your colored lights can spin, rise, or thrust in a random direction. Make sure you enjoy your fourth of July safely, but also armed with the knowledge that empowers you to understand how the most spectacular human-made light show of the year truly works!”

Fireworks have been around for more than a millennium, and universally contain the same four stages: a lift charge, a fuse, a burst charge, and stars. Yet even though we don’t particularly think about it frequently, quantum physics underlies each and every one of these stages, and is absolutely required if we want to understand how the light and color we see arises from simply heating/igniting different elements, ions, and chemical compounds.

Come celebrate the Fourth of July with a little science knowledge about fireworks, no matter where in the world you’re located!

What Is The Smallest Possible Distance In The …

What Is The Smallest Possible Distance In The Universe?

“At present, there is no way to predict what’s going to happen on distance scales that are smaller than about 10-35 meters, nor on timescales that are smaller than about 10-43 seconds. These values are set by the fundamental constants that govern our Universe. In the context of General Relativity and quantum physics, we can go no farther than these limits without getting nonsense out of our equations in return for our troubles.

It may yet be the case that a quantum theory of gravity will reveal properties of our Universe beyond these limits, or that some fundamental paradigm shifts concerning the nature of space and time could show us a new path forward. If we base our calculations on what we know today, however, there’s no way to go below the Planck scale in terms of distance or time. There may be a revolution coming on this front, but the signposts have yet to show us where it will occur.”

If you went down to smaller and smaller distance scales, you might imagine that you’ll start to see the Universe more clearly and in higher resolution. You’ll be able to hone in on the fundamental properties of nature, and glean more information the deeper you go. This is true, but only up to a point. Beyond that, you start running into the inescapable quantum rules that govern the Universe, and that means there’s a fundamental scale at which our best laws of physics cannot be trusted any longer.

That scale is the Planck scale, and for distances, it corresponds to about 10^-35 meters. It really is a problem for physics, and it’s high time you understood why.

Could An Incompleteness In Quantum Mechanics L…

Could An Incompleteness In Quantum Mechanics Lead To Our Next Scientific Revolution?

“But in the quantum Universe, this notion of relativistic causality isn’t as straightforward or universal as it would seem. There are many properties that a particle can have — such as its spin or polarization — that are fundamentally indeterminate until you make a measurement. Prior to observing the particle, or interacting with it in such a way that it’s forced to be in either one state or the other, it’s actually in a superposition of all possible outcomes.

Well, you can also take two quantum particles and entangle them, so that these very same quantum properties are linked between the two entangled particles. Whenever you interact with one member of the entangled pair, you not only gain information about which particular state it’s in, but also information about its entangled partner.”

One of the most important ideas in classical physics are those of locality and causality: that objects in close proximity can affect one another through the forces they exert on one another, which are limited by the speed of light. But quantum mechanics turns much of that on its head, where locality doesn’t appear to be a fundamental property of reality at all. Yet one of the most remarkable ideas of all out there conjectures that quantum gravity, which contains fundamental non-localities, could be described by variables that completely explain what we view as non-locality in standard quantum physics.

Could this be right? Lee Smolin is giving a talk on that today, and I’ll be live-blogging it as it happens. Don’t miss this one-of-a-kind event!

Could An Incompleteness In Quantum Mechanics L…

Could An Incompleteness In Quantum Mechanics Lead To Our Next Scientific Revolution?

“But in the quantum Universe, this notion of relativistic causality isn’t as straightforward or universal as it would seem. There are many properties that a particle can have — such as its spin or polarization — that are fundamentally indeterminate until you make a measurement. Prior to observing the particle, or interacting with it in such a way that it’s forced to be in either one state or the other, it’s actually in a superposition of all possible outcomes.

Well, you can also take two quantum particles and entangle them, so that these very same quantum properties are linked between the two entangled particles. Whenever you interact with one member of the entangled pair, you not only gain information about which particular state it’s in, but also information about its entangled partner.”

One of the most important ideas in classical physics are those of locality and causality: that objects in close proximity can affect one another through the forces they exert on one another, which are limited by the speed of light. But quantum mechanics turns much of that on its head, where locality doesn’t appear to be a fundamental property of reality at all. Yet one of the most remarkable ideas of all out there conjectures that quantum gravity, which contains fundamental non-localities, could be described by variables that completely explain what we view as non-locality in standard quantum physics.

Could this be right? Lee Smolin is giving a talk on that today, and I’ll be live-blogging it as it happens. Don’t miss this one-of-a-kind event!

No, Quantum Tunneling Didn’t Break The S…

No, Quantum Tunneling Didn’t Break The Speed Of Light; Nothing Does

“You might think, based on what you just read about the speed of quantum tunneling being instantaneous, that this means that particles can travel infinitely fast, breaking the speed of light, through a quantum mechanical barrier of finite, non-zero thickness. That’s the misinterpretation that always crops up, and how people fool themselves (and unscrupulous news organizations try to fool you) into thinking they’re breaking the speed of light.

But all that’s happening here is a portion of the quantum particles found in the pulse tunnels through the barrier, while the majority of the particles does what tennis balls do: they bounce back, failing to arrive at the destination. If you can front-load which particles make it through the barrier, preferentially cutting off the particles in the back of the pulse, you’ll falsely measure a faster-than-light speed, even though no individual particle actually breaks the speed of light.”

For the first time, researchers have measured what the speed of quantum tunneling is, and found that it was consistent with an instantaneous transition. If you’re in a quantum configuration that keeps you bound, or on one side of a barrier, tunneling can enable you to become unbound, or arrive on the other side of the barrier. But that doesn’t mean you can physically travel a finite distance through that barrier instantaneously, or faster-than-light. You can’t.

Here’s the real story, with an extra bonus of how this story (and ones like it) get mis-reported all the time.

Regular

inthenoosphere:

“Everything we call real is made of things that cannot be regarded as real.”

— Niels Bohr

Regular

inthenoosphere:

“Everything we call real is made of things that cannot be regarded as real.”

— Niels Bohr