Physics
drorzel | July 3, 2015Another busy week of physics-y blogging over at Forbes. I'm pretty bad about remembering to post pointers to individual posts here, but I can probably just about manage to do a weekly links dump of what I've been posting.
-- What's The Point Of Science Without "Eureka!" Moments? Picking up on a conversation I had at Convergence, about whether there's any point in doing experiments whose outcome won't be a surprise.
-- Should We Have An Institute For Low-Energy Fundamental Physics Picking up a bit from one of the Convergence talks, where Savas Dimopoulos suggested forming an institute to…
esiegel | July 1, 2015“Celebrate the independence of your nation by blowing up a small part of it.” -Summer of 4 ft. 2; The Simpsons
There are few things as closely associated with American independence as our willingness and eagerness to celebrate with fiery explosions. I refer, of course, to the unique spectacle of fireworks, first developed nearly a millennium ago halfway across the world.
Image credit: © Copyright 2005–2015 Capital Concerts, Inc.
But these displays don't happen by themselves; there's an intricate art and science required to deliver the shows we all expect. So what's the science behind…
drorzel | June 29, 2015I've been doing a bunch of conferencing recently, what with DAMOP a few weeks ago and then Convergence last week. This prompted me to write up a couple of posts about conference-related things, which I posted over at Forbes. These were apparently a pretty bad fit for the folks reading over there, as they've gotten very little traffic relative to, well, everything else I've posted during that span. Live and learn.
Anyway, I'm fairly happy with how both of those turned out, and on the off chance that they'll do better with the ScienceBlogs crowd, let me link them here:
-- What Are Academic…
drorzel | June 27, 2015I've been pretty quiet about educational matters of late, for the simple reason that I was too busy teaching to say much. The dust having settled a bit, though, I thought I would put some notes here about what I did this past term, and what worked.
I had two sections of the introductory Newtonian mechanics course in the Spring term; this was off the normal sequence for engineering majors (the engineers mostly take this in the Winter term of their first year), but this year we had yet another larger-than-expected engineering class, and needed to open another section. I picked up both of these…
esiegel | June 27, 2015“We are a singularity that makes music out of noise because we must hurry. We make a harvest of loneliness and desiring in the blank wasteland of the cosmos.” -Jack Gilbert
This past week at Starts With A Bang saw five new stories about the Universe, from our own home planet to topics about the birth of the Universe (and how we know it broke down that way), as well as our limits. Check out what we’ve covered:
Newton's random apple (for Ask Ethan),
Velociprincesses (for our Weekend Diversion),
The first bone of the Milky Way's skeleton (for Mostly Mute Monday),
Exoplanets & the search for…
esiegel | June 25, 2015“Electricity can be dangerous. My nephew tried to stick a penny into a plug. Whoever said a penny doesn’t go far didn’t see him shoot across that floor. I told him he was grounded.” -Tim Allen
Static electricity is often the first exposure to physics beyond gravity that we encounter in our lives. Simply rub a balloon against a piece of fabric, and you can stick it to almost anything (or anyone) you like, possibly to their chagrin.
No idea where this image came from. But it’s maybe the best one I’ve ever seen.
But the way you probably learned that it happens -- rub two materials together,…
drorzel | June 25, 2015I spent the last few days in Ontario, attending the Convergence meeting at the Perimeter Institute. This brought a bunch of Perimeter alumni and other big names together for a series of talks and discussions about the current state and future course of physics.
My role at this was basically to impersonate a journalist, and I had a MEDIA credential to prove it. I did a series of posts at Forbes about different aspects of the meeting:
-- The Laser Cavity was Flooded: a revisiting of the idea of True Lab Stories, which was a loose series of funny disaster tales from the early days of…
drorzel | June 19, 2015I've been really busy with year-end wrap-up stuff, but have also posted a bunch of stuff at Forbes. which I've fallen down on my obligation to promote here... So, somewhat belatedly, here's a collection of physics-y stuff that I've written recently:
-- Using Atoms To Measure Tiny Forces: A post reporting on some very cool atom interferometry experiments, one working to measure the very tiny (but known to exist) force of gravity, the other searching for a possible "fifth force" sort of thing.
-- Making And Shaking New Materials With Ultracold Atoms: A post reporting on a couple more DAMOP…
esiegel | June 17, 2015“Scientific ideas should be simple, explanatory, predictive. The inflationary multiverse as currently understood appears to have none of those properties.” -Paul Steinhardt, 2014
Cosmic inflation is alternately talked about by serious scientists as either the definitive beginning to our Universe, the thing that happened before and set up the Big Bang with absolute certainty, or a speculative fiction that can never be falsified, leading to nothing but untestable predictions and things that only mattered after-the-fact of their discovery.
Image credit: Bock et al. (2006, astro-ph/0604101);…
esiegel | June 12, 2015“Nothing is lost… Everything is transformed.” -Michael Ende
If you take all the kinetic motion out of a system, and have all the particles that make it up perfectly at rest, somehow even overcoming intrinsic quantum effects, you'd reach absolute zero, the theoretically lowest temperature of all. But what about the other direction? Is there a limit to how hot something can theoretically get?
Image credit: A.Greg; Wikimedia Commons user Greg L.
You might think not, that while things like molecules, atoms, protons and even matter will break down at high enough temperatures, you can always…
esiegel | June 11, 2015“Time is a sort of river of passing events, and strong is its current; no sooner is a thing brought to sight than it is swept by and another takes its place, and this too will be swept away.” –Marcus Aurelius
There are four known fundamental forces: gravitation, electromagnetism, the strong nuclear force and the weak nuclear force. But while we often speak of gravitation as an attractive force between masses (or anything with energy), of the electric force as charged particles attracting or repelling, of quarks and gluons attracting one another and keeping nuclei bound together, we describe…
esiegel | June 10, 2015“When it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images.” -Niels Bohr
Shortly after the Big Bang, the first nuclear fusion reactions occurred in the Universe, filling it with hydrogen, helium, and little else. Billions of years later, huge numbers of stars have lived and died, creating copious amounts of heavy elements, running the full gamut of the periodic table.
Image credit: Theodore Gray, via http://theodoregray.com/periodictable/Posters/index.posters.html.
After all this time, hydrogen is…
esiegel | June 10, 2015Although physicists are well-known for their quirky personalities, the in-joke among ourselves is our extremely nerdy sense of humor, telling jokes about our field, our equations, and of course, the legends in our field. These range from the subtle (Schrodinger walks into a bar, and also he doesn't), to the mischievous (Heisenberg gets pulled over by a police car. "Do you know how fast you were going?" "I have no idea, officer, but I know exactly where I am!"), and beyond.
Image credit: Courtesy of peterdsmith.com.
But one of the field's most iconic personas -- Niels Bohr -- inspired a…
esiegel | June 9, 2015If we want to understand the Universe at a fundamental level -- all the forces on all scales -- the biggest obstacle facing us is to come up with a correct, consistent, testable and verifiable theory of quantum gravity. To no one's great surprise, we're not quite there yet.
Image credit: Lee Smolin's book at Amazon.
In 2001, Lee Smolin -- one of the leading thinkers in quantum gravity -- made the bold prediction that,
“We shall have the basic framework of the quantum theory of gravity by 2010, 2015 at the outside.”
While we're not at all there yet, it's still fascinating in its own right…
drorzel | June 9, 2015I'm at DAMOP this week, though it took longer to get here than it should've-- severe storms yesterday canceled the flight I was supposed to take from Baltimore to Columbus, so I had to rebook to the 6am departure this morning, whee. I think this is the first time I've ever had a flight canceled while I was at the airport, though which is kind of amazing.
Anyway, I missed most of the morning session, and I'm short on sleep, but I saw some cool talks already, and expect to write about some of them tomorrow. For the moment, though, here's a post I wrote for Forbes yesterday talking about why…
esiegel | June 5, 2015“I just think too many nice things have happened in string theory for it to be all wrong. Humans do not understand it very well, but I just don’t believe there is a big cosmic conspiracy that created this incredible thing that has nothing to do with the real world.” -Edward Witten
It's a difficult fact to accept: our two most fundamental theories that describe reality, General Relativity for gravitation and the Standard Model / Quantum Field Theory for the other three forces, are fundamentally incompatible with one another. When an electron moves through a double slit, for example, its…
drorzel | June 5, 2015I'm massively short on sleep today, and wasn't going to blog until I saw somebody on Facebook mention that June 5th 1995 is the date of record for the first Bose-Einstein condensate at JILA in Boulder. I couldn't let that pass, so I wrote it up for Forbes:
Twenty years ago, in the summer of 1995, I was a young grad student having just finished my second year at Maryland, and one morning I packed into the conference room at the National Institute of Standards and Technology (NIST) in Gaithersburg (where I worked in the group of Bill Phillips) with most of the rest of the Atomic Physics…
drorzel | May 31, 2015Over at Wired, Rhett has a post providing mathematical proof that he takes too many photos. As is traditional, he includes homework at the end of the post, specifically:
Now it is your turn. Find the number of photos you have taken each year. Is it possible for you to detect changes in your life by significant changes in the image rate? Maybe you purchased a new phone or had a new addition to your family which resulted in an increase in images. That would be cool if you could see that in your data.
Well, I can't really resist a challenge like that, so I went looking at my own photo…
esiegel | May 29, 2015“One feels that the past stays the way you left it, whereas the present is in constant movement; it’s unstable all around you.” -Tom Stoppard
You might best know Einstein for E=mc^2, but I would argue that the far greater contribution was the development of relativity. Think about the following: if you strike the upper atmosphere with a cosmic ray, you produce a whole host of particles, including muons. Despite having a mean lifetime of just 2.2 microseconds, and the speed of light being 300,000 km/s, those muons can reach the ground!
Image credit: Pierre Auger Observatory, via http://…
esiegel | May 29, 2015Does a black hole have a shape? Is there a front and back or side view? Does it look the same from all vantage points?
When you think about a black hole, you very likely think about a large amount of mass, pulled towards a central location by the tremendous force of gravity. It's not all that different from our own Sun, which is the largest mass in town. Some 300,000 times as massive as Earth, despite its rotation, the Sun is almost perfectly spherical, differing by less than 0.0001%.
Image credit: Gary Palmer, July 2005, using a violet calcium-K filter.
While black holes themselves may be…