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“As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.” -Albert Einstein If you create an entangled pair of particles, and stretch them apart as far as you want, the entanglement remains. If you make a measurement of one particle’s quantum state, you immediately -- and this is truly instantaneous -- learn the quantum state of the other. This is true whether the other particle is meters, kilometers, astronomical units or light years away. Schematic of the third Aspect experiment testing quantum non-locality.…
"The whole edifice of modern physics is built up on the fundamental hypothesis of the atomic or molecular constitution of matter." -C. V. Raman As far as humans have figured out, there are four fundamental forces in the Universe: the three of the Standard Model (electromagnetism, the weak and strong nuclear forces) and General Relativity, our theory of gravitation. It’s the great hope of many that a quantum theory of gravitation will someday emerge, and that all four forces could be unified into a single framework. Among others, this is the dream of string theory. The four forces (or…
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." -Frederick S. Perls, quoting Einstein The Universe we can see and access is certainly a big place. We see that it goes on for 46 billion light years in all directions, full of stars, galaxies, matter and radiation wherever we look, consistent with an origin in a hot Big Bang. But beyond what we can see, there ought to be more Universe just like our own, originating from either the same Big Bang, or possibly, if inflation is correct, from other Big Bangs at later or earlier times…
"This isn't my life anymore, Mulder. I'm done chasing monsters in the dark." -Dana Scully, X-files One of the most exciting things a scientist can experience is when they look at a sample of data, expecting to not see a particular exciting effect, and yet, something’s there. Immediately, you have to check yourself: what are all the other things it could be? What are the mundane possibilities that could mimic that effect? And what can I do, if anything, to rule them out? Whenever you have a new idea, your main job, first and foremost, is to try and blow the biggest holes in it you possibly can…
"Do I believe, for example, that by using magic I could fly? No. How would you get around gravity? Impossible. Do I believe that I might be able to project my consciousness into a very, very vivid simulation of flying? Yeah. Yes, I've done that. Yes, that works." -Alan Moore If you possessed a computer with enough power, you could conceivably simulate the entire Universe. From the inception of the Big Bang, you could compute the positions and momenta of every particle and every interaction over time, across all 13.8 billion years. If your simulation was good enough, you could even account for…
"There have to be moments when you glimpse something decent, something life-affirming even in the most twisted character. That's where the real art lies." -Martin McDonagh There is a whole lot of cosmic detective work we can do to figure out the history of the Solar System. By examining the fossil record, geological deposits, the surface of other planetary bodies, meteors, asteroids and comets, the physics of the Sun, and the various components and layers of Earth, we can reconstruct when and where our planet and the rest of the Solar System came from. A massive collision of large…
"There will be peace when the people of the world, want it so badly, that their governments will have no choice but to give it to them. I just wish you could all see the Earth the way that I see it. Because when you really look at it, it's just one world." -Superman So, you want to shoot Earth’s garbage into the Sun, do you? From a physics point-of-view, this is difficult, but possible. First, you have to overcome the pull of Earth’s gravity, and escape into space. Next, you have to take into account the fact that Earth orbits the Sun at 30 km/s, and to fall into the Sun, you need to take…
"Its continuing mission: to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no one has gone before." -Star Trek, in many incarntions When Star Trek debuted 50 years ago, we didn’t know that there would be regions of the Universe that were forever inaccessible to humanity, nor that there would be galaxies permanently unreachable to us, even if we managed to develop near-light-speed travel technology. Yet thanks to the existence and dominance of dark energy today, that’s exactly the case. The only workaround, it appears, would be to develop faster-than…
“When we think about the present, we veer wildly between the belief in chance and the evidence in favour of determinism. When we think about the past, however, it seems obvious that everything happened in the way that it was intended.” -Michel Houellebecq If you take anything in the Universe and want to know what its size is, you simply take something whose length is known and compare. On microscopic scales, it isn’t much different: take something of a known wavelength -- like light or another matter particle -- and compare. If your wavelength is too big, you’ll pass right through; if your…
“Mapping out the elements in a star is like reading its DNA. We’re using those DNA readings to decode the history of the Milky Way from the stars that we can observe today.” -Steven Majewski Most of the stars in our Milky Way have long lives ahead of them, with dozens or even hundreds of orbits around the entire galaxy to come over their lifetimes. With hundreds of billions of stars involved in this cosmic dance, it stands to reason that on occasion, another nearby star will either gravitationally or cataclysmically (e.g., from a supernova) kick such a star to incredible velocities, perhaps…
"What, I sometimes wonder, would it be like if I lived in a country where winter is a matter of a few chilly days and a few weeks' rain; where the sun is never far away, and the flowers bloom all year long?" -Anna Neagle At some point in the future, the Sun, the giver and sustainer of nearly life on Earth as we know it, will run out of fuel. Powered by nuclear fusion, it turns hydrogen into helium, producing energy in the process. Yet the Sun has a finite mass, a finite rate-of-fusion, and someday will run out of hydrogen. When it does, bright as it may be today, it will cease to someday…
"The oldest and strongest emotion of mankind is fear, and the oldest and strongest kind of fear is fear of the unknown." -H.P. Lovecraft There’s a unique relationship between everything that exists in the Universe today -- the stars and galaxies, the large-scale structure, the leftover glow from the Big Bang, the expansion rate, etc. -- and the amount of time that’s passed since it all began. When it comes to our Universe, there really was a day without a yesterday, but how do we know exactly how much time has passed between then and now? The Universe's expansion rate is determined by the…
"They say the universe is expanding. That should help with the traffic." -Steven Wright Look out at a nearby object in our Universe, and you'll find that the amount of time you look back (in years) is pretty much exactly equal to the object's distance (in light years). But look far away, and these two numbers start to diverge. In our 13.8 billion year old Universe, in fact, we can see back up to 46 billion light years in any direction. If you think this number seems absurd, you're not alone. The GOODS-N field, with galaxy GN-z11 highlighted: the presently most-distant galaxy ever discovered…
"The world you see, nature's greatest and most glorious creation, and the human mind which gazes and wonders at it, and is the most splendid part of it, these are our own everlasting possessions and will remain with us as long as we ourselves remain." -Seneca Asking where in space the Big Bang happened is like asking where the starting point of Earth’s surface is. There’s no one “point” where it began, unless you’re talking about a point in time. The reality is that, as far as space is concerned, the Big Bang occurred everywhere at once, and we have the evidence to prove it. Our view of a…
“A human being is part of a whole, called by us the Universe, a part limited in time and space. He experiences himself, his thoughts and feelings, as something separated from the rest a kind of optical delusion of his consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and to affection for a few persons nearest us. Our task must be to free ourselves from this prison by widening our circles of compassion to embrace all living creatures and the whole of nature in its beauty.” -Albert Einstein If you're talking to someone across the same room, what the…
“I found I could say things with color and shapes that I couldn’t say any other way — things I had no words for.” –Georgia O’Keeffe The Standard Model is great at describing all the known particles we've ever observed and how they interact, but there are a number of important hints that it isn't all there is in the Universe. The existence of dark matter, dark energy, neutrino masses, the matter-antimatter asymmetry, the strong-CP and hierarchy problems all tell us that this collection of quarks, leptons, their antiparticles and the bosons we know are only part of the story. The particles and…
"Find a place inside where there's joy, and the joy will burn out the pain." -Joseph Campbell One of the cardinal rules of a black hole is that anything that falls inside the event horizon -- that crosses that invisible boundary -- can never escape. That's because the escape velocity from inside the event horizon is greater than the speed of light in a vacuum, c, a speed that nothing in this Universe can exceed. In flat space, it's easy to set up an infinite series of observers that all agree on the speed of light at different locations. Image credit: PixaBay user PixelAnarchy. But in…
"You can be the Moon and still be jealous of the stars." -Gary Allen Earlier this week, NASA announced the discovery of Asteroid 2016 HO3, calling it Earth’s second moon. And it turns out that this is an object in a stable orbit, the same distance from the Sun as the Earth, that can be found revolving around our world at a distance between 38 and 100 times the distance from us to the Moon. The orbits of all the known Potentially Hazardous Asteroids, as of 2013. This includes asteroids that have been gravitationally captured by the Earth-Sun system. Image credit: NASA/JPL-Caltech. But that…
"The sacred rights of mankind are not to be rummaged for among old parchments or musty records. They are written, as with a sunbeam, in the whole volume of human nature, by the hand of the divinity itself; and can never be erased or obscured by mortal power." -Alexander Hamilton Seen poking through a cloud, trees or other opaque materials, sunbeams are one of the most surprising natural phenomena, when you think about it. There’s always scattered, ambient sunlight in all directions, and the bright sunshine is never visible as a ray when there aren’t clouds. Public domain photo from Pixabay…
"The new claim now is [a] boson with a mass of 16.7 MeV. But they don’t say anything about what went wrong in their previous claims and why we should not take those claims seriously." -Oscar Naviliat Cuncic Everyone knows that the Standard Model of particle physics cannot be all there is. It does a fantastic job of describing the known particles and interactions, but many mysteries remain, including the origin of the matter-antimatter asymmetry, the existence of dark matter and dark energy, the origin of the interaction strengths of the particles, and why they have the mass values that they…