Dark energy highlights continued

Here is a great dark energy FAQ from Sean Carroll, a physicist at CalTech.

Einstein's greatest blunder (?)

In 1917 Einstein added a fudge factor, the cosmological constant, to the equations in his theory of general relativity. Before adding the constant, his equations showed the attractive force of gravity would cause the universe to implode in a Big Crunch. The constant kept Einstein's picture of the universe static – neither expanding nor contracting.

When Edwin Hubble discovered that the universe was expanding (the rate of expansion is what won this year's Nobel Prize), Einstein threw out the cosmological constant, declaring it his greatest blunder.

But the cosmological constant may still work. In fact, without the constant, the age of the universe is calculated to be much younger than the oldest observed stars. Since this makes no sense, the constant may hold validity.

How do spacetime and quantum field theory ultimately fit together? That has been the big looming question. One proposed “quantum correction” to classical mechanics is quantum mechanical vacuum energy. If there is such a vacuum energy, it may be associated with the cosmological constant.

But there is still an incredibly gaping margin of error: when physicists calculated the vacuum energy they came up with an answer 120 orders of magnitude (10^120 times) greater than what we actually observe. It would take me 2 minutes just to write out all those zeroes.

(hey you physics people, want to delve further?)

With all the advances in modern physics and the accomplishments highlighted by this year's Nobel Prize, there still remains an entire universe (or perhaps multiverses?) of mysteries.

Into the Future...

For the time being, budget cuts caused NASA to scrap its projects investigating dark energy using the James Webb Telescope. Fortunately, in 2019 the European Space Agency plans to step in with its Euclid mission.

The Large Synoptic Survey Telescope (LSST) in Chile will become another source of data for dark energy research.

Dark energy gets attention from Nobel Prize in Physics

*picture from NASA

Three American-born physicists won the Nobel Prize in Physics on Tuesday. Thirteen years ago they first made the startling announcement that the universe is expanding at an accelerating rate. They made the discovery by measuring the brightness of type 1a supernovae, explosions of small stars known as white dwarfs that can outshine an entire galaxy and can radiate as much energy as our sun will in its entire lifetime. The measurements showed that the supernovae were dimmer than what was expected, suggesting that galaxies were moving apart at an increasing rate.

At the time scientists were skeptical of the results – the prevailing view was that the universe was slowing down in its expansion. Yet two teams in competition with each other (one led by Saul Perlmutter of the Lawrence Berkeley National Laboratory, and the other headed by Brian Schmidt of the Australian National University in Canberra and Adam Reiss of the Space Telescope Science Institute and Johns Hopkins University) used independent lines of evidence to reach the same results.

The Nobel Prize brings attention to the study of a mysterious component of the universe called dark energy.


What is dark energy?

The simple answer: we don't really know, but physicists believe that dark energy is the “thing” that causes the universe to accelerate in its expansion. It's a little unbelievable that dark energy makes up about 73% of the universe, and yet we know so little about it. There are three properties to note. First, look at the name: dark. It is 'dark' because we don't see it; we do not observe dark energy interacting with matter at all. Second, it is smoothly distributed. The density of dark energy is uniform throughout space. And third, it is persistent. Unlike particles of matter, dark energy doesn't cluster together or dilute away.

The difference between dark energy and dark matter

Dark energy is not the same thing as dark matter. Again, look at the name. Dark energy is energy – it doesn't consist of particles. Dark matter consists of particles of matter. Physicists think it's there but they have yet to directly detect the particles.  However, they have observed gravitational influences (in settings like galaxies, clusters, large-scale structure, and microwave background radiation) that they attribute to clusters of dark matter.

Dark matter makes up about 23% of the universe. Actual matter – the stuff that the Earth is made up of, and the stuff that you and me interact with on a day-to-day basis – makes up less than 5% of the universe. Crazy.

More to come soon...

Depressing study shows people are depressed

Do studies predict the worst? In Nature’s Trend Watch last week the prevalence of obesity in the US and the UK is projected to grow from 32% in 2007-08 to 50% in 2030 for men, and from 35% to 45% for women. One obese person out of three people seems high enough as it is. But one out of two people is just…depressing.

Another study in Nature reports that mental disorders affect over one third of all Europeans. Can they do a follow-up study of how many of those Europeans got anxious or depressed from reading all the other depressing studies out there?

I generally read study results as interesting opinions that could potentially become facts…or not. Just something to think about. But it is irritating when magazines take those studies and tell you to make changes with your life. “Study says chocolate goes straight to your hips. Try eating vegan tofu desserts instead!” And then “Study says chocolate has antioxidants. Go to See’s Candies today!”

I’ll go be happy now and distract myself on Youtube.

Building a toolbox for science and math literacy

I'm very excited: an opinion article I wrote about why we need more exposure early on for science and math education is published in the San Diego Union-Tribune today! The basics:

1) Science and math can be awesome!

2) Learning math is like investing in a good toolbox to build a house.

3) Having a mentor/having a challenge is invaluable.

You can read more about good toolboxes that help our less-than-stellar education system in science and math here:

http://www.signonsandiego.com/news/2011/aug/20/building-a-toolbox-for-science-and-math-literacy/

Palm trees threatened by invasive pest

What do you think of when you picture southern California? The breezy beach, a cloudless, sunny sky…and maybe some palm trees? Okay, how about a lot of palm trees. They are everywhere. 

Let’s hope our palm trees stick around. 

(photo credit: John Kabashima, UC Cooperative Extension)

The red palm weevil, a small beetle-like pest that can quickly kill palm trees, was first discovered in California last year. Weevil larvae burrow deep into the trunks of palms and grind its insides into mush. Adult weevils munch on palms, including the top-most leaves.

You can read more about it in an article I wrote for this month’s issue of CAPCA’s Adviser magazine, “What’s Bugging California’s Palm Trees?” I had the opportunity to interview Mark Hoddle, an entomologist at UC Riverside who researches the red palm weevil and conducts field work to contain the pest. He keeps a well-documented, up-to-date blog here. 

Speculated to have come from Southeast Asia, its invasion now threatens palms in urban areas, native palms in the desert, and California’s date crops and palm nurseries. In May this year, a second weevil species was caught in a trap in San Diego County. Traps are currently set up around the first sighting in Laguna Beach and along the Mexico-CA border (where the second species was found). 

Ever since doing this article I have put on my palm tree glasses. As a southern California native, I am so used to palm trees that they blend into the background. They weren’t so different from any other tree. But knowing that they are iconic to our state, especially for those who come to visit, I can see ‘em now! 

Pale Blue Dot Animations

There is a whole world to explore within a pinhead. Consider that an atom is roughly seven orders of magnitude smaller than a pinhead, something you can still see with the naked eye. If you blew up that pinhead to the size of the earth, you could at last hold an atom in your hand like you would, say, a water balloon.

And then there is Carl Sagan shrinking the massive size of the earth to a pale blue dot.

This "joyful, sad, sweet, and wonderful" animation posted on PBS Nova's blog got me thinking. It captures an excerpt from Carl Sagan's book A Pale Blue Dot.


Pale Blue Dot - Animation from Ehdubya on Vimeo.

Science is a tool that can help us better appreciate the beauty of nature. It doesn't reduce the mystery and art of life by explaining/revealing its underlying mechanisms; rather the opposite, it gives us more perspective.

Taking a walk outside helps me see I'm a tiny creature amidst people, cars, buildings, trees, mountains... I'm still trying to imagine zooming out on me, my city, California, the US, and then the earth until there is nothing but a pale blue dot...

"Surely you're joking, Mr. Feynman!"

Richard Feynman was that rare combination of genius and accessibility to the non-physicist. If there was one thing he was confident in it was sitting down with a seemingly impossible puzzle until he solved it. He also played the bongos, told funny stories, and pulled a great poker face on the (in)appropriate occasion.

If you read any of his stories from the book "Surely You're Joking, Mr. Feynman!", I recommend Safecracker Meets Safecracker. It's a great example of how Feynman rolls, and I cracked a grin (bad pun?) while reading it.

Feynman developed an active observance of social irresponsibility from the great mathematician John Von Neumann, who gave him this advice:

You don't have to be responsible for the world you're in.

Perhaps due to this lack of seriousness, Feynman romps through some entertaining twists and turns in life.

Read The Dignified Professor to find out how the whole business that got him the Nobel Prize "came from piddling with a wobbling plate". Burned out from working on the atomic bomb project during WWII, he felt an unusual twinge of disgust for physics in his new life as a young college professor. He asked himself why he had once enjoyed doing physics and realized it was because he used to do whatever he felt like doing - i.e. play with it.

An example of Feynman's idea of play: figuring out how to determine the curve for water running out of a faucet.

So when he was at the cafeteria he saw a guy throw a plate in the air and noticed the plate wobbled. For fun he set out to determine the motion of the plate wobbles. "It was effortless. It was easy to play with these things. It was like uncorking a bottle: Everything flowed out effortlessly. I almost tried to resist it!"

Maybe a little more effortless for him than for the average person, but he set out to actively play just like anyone might. In science I see this sense of play slip through fingers like sand (I include my own undergraduate experiences here). It gets replaced with talk of "the future of science and the betterment of society", or maybe just getting a good grade.

At any rate Feynman's stories are a good read and he packs a joy for physics into them. 

Why promote science fairs

This week the LA Convention Center was filled with poster boards and precocious students for the Intel International Science and Engineering Fair. The biggest science fair in the world attracts more than 1,500 participants from 65 countries. This year’s $75,000 grand prize went to Matthew Fedderson and Blake Marggraff of Lafayette, California for their research on treating simulated cancer cells with Compton-scattered secondary radiation. Nothing less than professional-level science projects (albeit with the help of a scientist mentor in most cases) can be expected from ISEF.

I participated in the fair for a day as a volunteer interpreter and was able to meet some of the Japanese students. They qualified by winning national-level high school science fairs in Japan – impressive students on paper and in person.

In science fairs the first hurdle is to come up with a good question. You can’t just ask a big question like, “How can I cure cancer?” The best questions come from a simple observation in your surroundings. The next hurdle is to design a clean, simple experiment to test your hypothesis.

I helped out with a student who experimented with liquid nitrogen. While playing with liquid nitrogen he noticed that some materials boil within the nitrogen, calm down, and then re-boil. He asked, “Why does re-boiling occur?” He observed a simple mechanism and being curious, wondered how it works. After testing re-boiling for many materials he found that re-boiling occurred the most for materials with high thermal conductivity.

With the help of a high-speed camera he also discovered that a film of bubbles collects on the material before it re-boils. He then tested whether the film of bubbles causes re-boiling by breaking the film with a heating wire. That’s the part of the experiment that I really like – he found a way to disrupt the film of bubbles and observe what happens in its absence. It’s a well-designed experiment. He found that when he applied more current to the heating wire, the material finished reboiling faster. The conclusion: cooling can be accelerated if the film of bubbles is broken by non-uniform heating.

The schedule for the students is pretty grueling. They are at the convention center from 7am to 6pm, where they present their experiment to judges in English, a second language for them. One of the people from the Japanese team remarked that these students can present their science projects better in English than they can do small talk in English. Ask them how surface area affects reboiling in liquid nitrogen and they’ll answer straight away. But as a judge if you try to break the ice with, “Have you visited Disneyland yet?” they get a little thrown off.

I was very happy to meet these students. They were mature and at the top of their game. One of them gave me a Japanese fan, too! There was a clip from NPR that pointed out that kids (especially those at this science fair) can contribute to science and offer something different. Where an older, trained scientist may think that something will never work, a kid might look at something in a new way. She might ask, “Why not?”

UCR Science Lecture Series

Yesterday I went to a talk held at UCR as part of a science lecture series open to the public. Cheryl Hayashi, a biology professor at UCR, gave a talk on biomimetic technologies – innovations that imitate nature. Hayashi advocates that there is a lot to learn from nature. Shaped by natural selection over a super-human stretch of time, designs found in nature are often superior to manmade technologies.

Hayashi’s slight frame packs a bundle of energy and enthusiasm for her work. She wears comfortable shoes and slacks and sports hair slightly more fashionable than the average professor. “Do you see this here?” she asks as she walks from one side of the room to the other, making sure that everyone in the audience can see what she is pointing out. It is a picture of sand. “There are two eyes here,” she draws her hand over the picture, “and here are the legs coming out.” The audience “oooohs” in comprehension – now we see a spider camouflaging itself in the sand. Hayashi shoots a mischievous look at us and exclaims, “You guys will believe anything, huh!” She’s just kidding, though. She assures us there really is a spider there.

Hayashi's fascination with nature is infectious as she takes us through current technologies that imitate nature. She offers the example of a butterfly that does not use pigment to color its brilliant metallic blue wings. Instead the wings are made of tiny lens-like scales that nature has optically engineered to reflect blue wavelengths of light back to us. Sonar, often used by the military, has been used for much longer by bats and dolphins to detect their surroundings. Speedo recently developed swimsuits that mimic shark skin to create more efficiency for swimmers. And the inspiration for Velcro came to an inventor when he came back from a hike to find himself and his dog covered in fast-sticking seed burrs.

Hayashi herself works with spiders and researches spider silk. She urges us to imagine what it would be like to be a small spider interacting in a giant’s world. They need their silk to interact with their surroundings. Incredibly, spiders create 7 different kinds of silk. Hayashi’s lab measures the properties of the silk and researches how spiders produce it. Spider silk can stretch to twice its length without breaking and has superior strength, extensibility, and toughness compared to manmade materials. While a string of spider silk 1mm in diameter could lift a cat (11 pounds), a 20mm diameter string could lift a hippo (4400 pounds). That’s a tough string of silk.

Some promising applications for spider silk include tough, lightweight gear such as bullet-proof vests and medical products such as bandages and sutures. Spider silk also exhibits muscle-like properties: wetness and humidity cause the silk to contract. It could provide an alternative to artificial muscle tissue, which contracts through electrical impulses. Producing spider silk in mass quantities for commercial applications presents another challenge and opens a new topic of research.

After this talk I am left impressed by designs that occur in nature. I am also curious – what does Hayashi do with spiders she finds in her house? She wouldn’t squash them, would she? Perhaps she takes them with her to lab.

For more info on the Science Lecture Series, visit here!

Pirate puzzle added

In our continuing adventures with the unnamed pirate, he encounters tigers and treehouses in puzzle number 3. See if you can help the pirate solve the puzzle with your logic and wit here: Pirate Adventures with Math.

The Big One

In Japan they call it "Tokai", and here in California we call it the "Big One". It's that massive earthquake that you're waiting for if you live in an earthquake prone region, and in California it would occur on the San Andreas fault.


The LA Times has an interesting article about seismologists that are creating underground images near the San Andreas fault. It looks like pretty intense field work. The scientists set off explosions along the fault and record the speed of seismic waves as they travel through the Earth's crust. The recordings are used to generate underground images. "So far, they had put out more than 4000 seismomemters, and the night crew had set off more than 100 explosions."

The more we know about the structure of the San Andreas fault, the more we can determine the impact of shaking from an earthquake like the Big One. Previous studies project 2000 deaths, 50,000 injuries, and $200 billion in damage from a 7.8 quake near the fault. That's much less than the recent quake and tsunami in Japan, but still significant.

I like this Google map of the San Andreas fault. It’s easy to zoom in and pan around on the fault. It’s right up against the base of the mountain ranges in some areas.

Also a detailed site about the San Andreas here.

While this fault is above ground, I wonder how they are studying rifts that are under the ocean...

Quake devastation...and tracking what went wrong with Japan's nuclear reactors

At my house the TV is tuned to the Japanese channel for NHK’s coverage of the damage and devastation from Friday’s earthquake. It’s relentless coverage of the dead and missing, shots of people who have evacuated to shelters, bell chimes sounding new earthquake warnings, and the latest from the Fukushima power plant. 

Everyone is comparing the situation at Fukushima to past events: it’s worse than Three Mile Island but not as bad as Chernobyl. But will it become worse than Chernobyl? That’s unclear, but here are some sources to understand what is going on:

NPR has a visual guide to what went wrong inside the nuclear reactor. So far there have been explosions at 4 reactors. NPR is also tracking the latest news on the reactor.

A more detailed explanation of the fundamentals here.

Although people are concerned about the health effects of radiation exposure, this article from the Washington Post brings up the psychological damage that may have just as much significance.

And my summary from what I've gathered so far:

After the earthquake and tsunami the plant lost the necessary power to cool the fuel rods. The fuel rods contain fuel that generates heat through nuclear fission. The temperature of the fuel rods must remain stable to prevent a “nuclear meltdown” that could result in radiation leaks. With the cooling system failing, too much water boiled into steam and increased the pressure within the reactor. The power plant workers vented steam outside of the reactor to reduce the pressure, but they also added cooling water and caused hydrogen to build up inside the reactor. The steam and hydrogen gas were vented into the air and a hydrogen explosion occurred.

Also, I am following the updates on the situation at Fukushima because it's interesting and because there are health risks, but there is so much going on in Japan beyond what I can fathom. Ganbare Nippon!

Ars Technica science video contest winners

Last week Ars Technica chose the winners for their science video contest in December:
http://arstechnica.com/science/news/2011/02/ars-announces-the-science-video-contest-winners.ars

These videos were fun to watch, and they ALL succeed in teaching you something about science while entertaining you.

Two videos explain the concept of a fourth dimension. One of them has an excellent soundtrack and the other one has a really good narration.

There was also a video about the Doppler effect!! That's one of the physics concepts that is the most fun to explain to others...and in that video it looks really good when you animate the Doppler effect.

To explain how antibiotics work, one video animates M&Ms and Twizzlers to great effect.

Last but not least the Large Hadron Collider is explained without any talking. That one was exciting to watch. When they show the "99.9991%"-ish number, are they talking about the speed at which the protons are accelerated?

Man, it would be so fun to pull off a video on this level...