Category: physics

Quarks Don’t Actually Have Colors

Quarks Don’t Actually Have Colors

“We may call it color charge, but the strong nuclear force obeys rules that are unique among all the phenomena in the Universe. While we ascribe colors to quarks, anticolors to antiquarks, and color-anticolor combinations to gluons, it’s only a limited analogy. In truth, none of the particles or antiparticles have a color at all, but merely obey the rules of an interaction that has three fundamental types of charge, and only combinations that have no net charge under this system are allowed to exist in nature.

This intricate interaction is the only known force that can overcome the electromagnetic force and keep two particles of like electric charge bound together into a single, stable structure: the atomic nucleus. Quarks don’t actually have colors, but they do have charges as governed by the strong interaction. Only with these unique properties can the building blocks of matter combine to produce the Universe we inhabit today.”

At a fundamental level, forces like gravity are easy. There’s only one type of charge, mass/energy, and it’s always attractive. The electric force is a little more complex, with two types of fundamental electric charges, positive or negative, where like charges repel and opposite charges attract. But in the theory of the strong interactions, there are three fundamental types of charge, and that changes everything. We call this color charge because of a good analogy with how additive and subtractive colors work, but we can learn even more by investigating where the analogies break down.

Nature is bizarre, but if we’re careful we can understand it. Quarks don’t actually have colors, but what they do have may be even more interesting. Come find out about it today.

For those who want more precise information ab…

cosmicvastness: Astronomers Capture First I…


Astronomers Capture First Image of a Black Hole

The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was designed to capture images of a black hole. Today, in coordinated press conferences across the globe, EHT researchers revealed that they have succeeded, unveiling the first direct visual evidence of a supermassive black hole and its shadow.

The image reveals the black hole at the centre of Messier 87, a massive galaxy in the nearby Virgo galaxy cluster. This black hole resides 55 million light-years from Earth and has a mass 6.5 billion times that of the Sun.

Supermassive black holes are relatively tiny astronomical objects — which has made them impossible to directly observe until now. As the size of a black hole’s event horizon is proportional to its mass, the more massive a black hole, the larger the shadow. Thanks to its enormous mass and relative proximity, M87’s black hole was predicted to be one of the largest viewable from Earth — making it a perfect target for the EHT. 

The shadow of a black hole is the closest we can come to an image of the black hole itself, a completely dark object from which light cannot escape. The black hole’s boundary — the event horizon from which the EHT takes its name — is around 2.5 times smaller than the shadow it casts and measures just under 40 billion km across.

Credit: ESO

I’m just mindblown.

Are you an expert on fake physics? The kind th…

Are you an expert on fake physics? The kind that exists in sci-fi movies? What if I asked you something about those? Confirm or deny if they're fake??

I’m an ‘expert’ in physics so I guess that makes me an expert in fake physics. I’ll do my best to answer any question you have

humanoidhistory: The rings of Saturn, observe…


The rings of Saturn, observed by the Cassini space probe on May 3, 2005.


Ask Ethan: What Is An Electron?

Ask Ethan: What Is An Electron?

“Please will you describe the electron… explaining what it is, and why it moves the way it does when it interacts with a positron. If you’d also like to explain why it moves the way that it does in an electric field, a magnetic field, and a gravitational field, that would be nice. An explanation of charge would be nice too, and an explanation of why the electron has mass.”

When we, as physicists, speak about fundamental particles, we refer to the smallest constituents of matter and energy that cannot be divided any farther. There are two classes of such particles, fermions (which can be matter or antimatter) and bosons (which are neither), and they behave in rather unintuitive ways, since they’re quantum in nature. But even though there are many properties of quantum particles that are inherently uncertain, there are some that are intrinsic and perfectly well-known. These are the properties that define each type of particle and allow us to discern them from all others.

Here is, to the best of our knowledge, what the electron truly is, along with some fundamental questions we still have yet to answer about them!

What should I do/say to impress someone who is…

What should I do/say to impress someone who is an astrophysics professor?

Do not mention quantum physics, only the large scale exists. All physicist like it when someone compliments our minds cause we’re very egocentric and desperate. Do not mention Interstellar

One Of These Four Missions Will Be Selected As…

One Of These Four Missions Will Be Selected As NASA’s Next Flagship For Astrophysics

“Choosing which of these missions to build and fly will, in many ways, inform our plans for the next 30 years (or more) of astronomy. NASA is the pre-eminent space agency in the world. This is where science, research, development, discovery, and innovation all come together. The spinoff technologies alone justify the investment, but that’s not why we do it. We are here to discover the Universe. We are here to learn all that we can about the cosmos and our place within it. We are here to find out what the Universe looks like and how it came to be the way it is today.

People will always argue over budgets — the penny-pinchers are always happy to propose something that’s faster, cheaper, and worse — but the reality is this: the budget for NASA Astrophysics as a whole is just $1.35 billion per year: less than 0.1% of the federal discretionary budget and less than 0.03% of the total federal budget. And still, for that tiny amount, NASA has steadily built a flagship program that’s the envy of the free world.”

Every 10 years, NASA performs a decadal survey, where it outlines its highest mission priorities for the next 10 years. The 2020 decadal is happening imminently, and once the recommendations are submitted to the National Resource Council at the National Academies of Science, the four flagship finalists will be ranked. This will determine NASA astrophysics’ direction for the 2030s.

James Webb is the flagship for the 2010s; WFIRST is it for the 2020s. What will we choose for the 2030s? It will be one of these four finalists! Dream big, everyone.


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.