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patrick tinkham
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“This null result — the fact that there was no luminiferous aether — was actually a huge advance for modern science, as it meant that light must have been inherently different from all other waves that we knew of. The resolution came 18 years later, when Einstein’s theory of special relativity came along. And with it, we gained the recognition that the speed of light was a universal constant in all reference frames, that there was no absolute space or absolute time, and — finally — that light needed nothing more than space and time to travel through.”

In the 1880s, it was clear that something was wrong with Newton’s formulation of the Universe. Gravitation didn’t explain everything, objects behaved bizarrely close to the speed of light, and light was exhibiting wave-like properties. But surely, even if it were a wave, it required a medium to travel through, just like all other waves? That was the standard thinking, and the genius of Albert A. Michelson was put to work to test it. Because, he reasoned, the Earth was moving around the Sun, the speed of light should get a boost in that forward direction, and then have to fight that boost on the return trip. The perpendicular direction, on the other hand, would be unaffected. This motion of light should be detectable in the form of interferometry, where light was split into two perpendicular components, sent on a journey, reflected, and then recombined.

The null results of this experiment changed the Universe, and the technology is still used today in experiments like LIGO. Come learn about the greatest failed experiment of all-time!

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#Prague historical center is one of largest in the world, but you can find a lot of beauty even outside - this square is 2-3 subway stops from our #accommodation.
There are 4 subway stations near to our Grand #Hotel #Praha.

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“With two up quarks -- two identical particles -- in the ground state, you'd expect that the Pauli exclusion principle would prevent these two identical particles from occupying the same state, and so one would have to be +1/2 while the other was -1/2. Therefore, you'd reason, that third quark (the down quark) would give you a total spin of 1/2. But then the experiments came, and there was quite a surprise at play: when you smashed high-energy particles into the proton, the three quarks inside (up, up, and down) only contributed about 30% to the proton's spin.”

You might think that the proton, made up of three spin=1/2 quarks, has a spin of 1/2 for that exact reason: you can sum three spin=1/2 particles together to get 1/2 out. But that oversimplified interpretation ignores the gluons, the sea quarks, the spin-orbit interactions of the component particles. Most importantly, it ignores the experimental data, which shows that the three valence quarks only contribute about 30% of the proton’s spin. Our model of the proton has gotten more sophisticated over time, as advances in experiment and in Lattice QCD calculations have shown that the majority of the proton’s spin comes from the internal gluons, not from the quarks at all. The rest comes from orbital interactions, with the low-momentum gluons requiring a more sophisticated electron-ion collider to experimentally examine.

After decades of mystery, we’re finally closing in on exactly why a proton spins. Find out the surprising physics behind the simple answer!

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This metallic “space fabric” was created using 3-D printed techniques and provides flexible materials for use in space. From shielding a spacecraft from meteorites or use in astronaut spacesuits, these materials could have a wide range of uses. Find out more: http://go.nasa.gov/2oJfWKu
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“They showed how aging stars that were massive enough, such as Red Giants and Supergiants, could find it energetically feasible to create all the elements up to iron in their cores. The even-higher elements could be produced in the extreme conditions of a supernova explosion, upon which the full gamut of elements would be released into space.”

Throughout the 1940s, 50s and even 60s, a debate as to the origin of the Universe raged in astrophysics. Was the Big Bang theory, where the Universe emerged from a hot, dense state some finite time ago, or the Steady-State theory, where the Universe always had the same density and properties, correct? Two very different pictures of the Universe emerged, but more interestingly, they each predicted a very different origin for the chemical elements in the Universe. The Big Bang theorists preferred a Universe where the hot, dense stage of the early, post-Big Bang Universe created the heavy elements, while the Steady-State camp predicted those elements would originate in stars. 60 years ago, in 1957, theory and experiment came together to show that stellar nucleosynthesis is the answer.

That didn’t mean the Big Bang was wrong, but it did mean that the build up of the periodic table didn’t happen early; it happened late! Come get the full story thanks to the incredible Paul Halpern.

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The team engineered molecules that accomplish something viruses do much better than the human immune system; namely, targeting specific carbohydrate molecules that appear on the surfaces of bacterial cells.

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Solar storms not only cause regions of excessive electrical charge in the upper atmosphere above Earth’s poles, but can also do the exact opposite…cause regions that are nearly depleted of electrically charged particles. This finding could lead to improved radio communication and navigation systems for the Arctic. Find out more: http://go.nasa.gov/2ovrotC
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“Nuclear fusion as a power source has never been given the necessary funding to develop it to fruition, but it’s the one physically possible solution to our energy needs with no obvious downsides. If we can get the idea that “nuclear” means “potential for disaster” out of our heads, people from all across the political spectrum just might be able to come together and solve our energy and environmental needs in one single blow. If you think the government should be investing in science with national and global payoffs, you can’t do better than the ROI that would come from successful fusion research. The physics works out beautifully; we now just need the investment and the engineering breakthroughs.”

Climate science is a hotly debated area, with many disputing the robustness and ethical motivations of the scientists in the field. But even if you throw everything we know about carbon dioxide, global warming, and climate change away, there’s still an energy crisis coming in the long term. The fact is, fossil fuels will someday, hundreds of years from now, run out if we extract and burn them all. Meanwhile, solar, wind, hydroelectric and other renewables will forever be inconsistent, and the infrastructure needed for using both generates large amounts of pollutants. But there is one power option that could satisfy everybody, while eliminating both pollution and the risks of running out of fuel or power inconsistency: nuclear fusion. While nuclear fission does have substantial downsides, there’s no risk of a meltdown with fusion.

All we need to do is reach the breakeven point, and we have four different approaches currently in progress. Come get the science today!

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“But you’ll never make a 13 TeV particle colliding two protons at the LHC; only a fraction of that energy is available to create new particles via E = mc^2. The reason? A proton is made of multiple, composite particles – quarks, gluons, and even quark/antiquark pairs inside – meaning that only a tiny fraction of that energy goes into making new, massive particles.”

The large hadron collider is the world’s most powerful particle accelerator, colliding two protons at energies of 6.5 TeV apiece. But you’ll never have the full 13 TeV of energy available for that collision, thanks to the fact that the proton itself is a composite particle, and that energy is distributed throughout its components. When you get a collision, only a fraction of that energy goes into the collision itself, while the rest remains in the other component particles. The way around this is to use fundamental particles. The electron is no good, because it loses too much energy when you accelerate it in a magnetic field; it’s charge-to-mass ratio is too high. But the electron has a high-mass cousin, the muon, that’s 206 times as massive. Even though the muon only lives for microseconds, the right accelerator might be able to take advantage of special relativity (and time dilation), bringing a muon/antimuon collider to life, and realizing the best of both worlds.

What are the prospects for a muon collider? They’re better than they’ve ever been, and just might save experimental particle physics!
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