The End of Dark Energy

picture of Harry KellerBy Harry Keller
Editor, Science Education

Dr. Peter A. Milne and his associates have found an unexpected and, to the cosmological community, startling result from their surveys of supernovae. This result illustrates both the consistent and varying nature of science at the same time.

Dr. Peter Milne

Dr. Peter Milne

We know from a great many astronomical observations that the universe has been expanding for a little short of 14 billion years and continues to expand. Because of gravity, everyone expected that this expansion was slowing over time with theories and measurements suggesting that this expansion would eventually coast to a very dilute universe drifting apart at ever slower speeds.

In the 1990s, some astronomers separately discovered that the universe is expanding ever more rapidly instead of the expected opposite slowing of expansion using measurements of he brightness of very distant supernovae. They received the Nobel Prize in physics for this work in 2011.

Stars can explode. One common explosion is called a nova. A much more cataclysmic and extremely brighter explosion is a supernova. Supernovae shine with a brightness that can exceed that of all of the hundred billion or so stars in its galaxy. For this reason, we can see them in distant galaxies that are barely visible in our best telescopes. A supernova is a rare event occurring about three times a century in a galaxy the size of our Milky Way. With hundreds of billions of galaxies, however, it’s not too hard to find hundreds each year using modern astronomical equipment.

A special sort of supernova created when the two stars in a binary star system go through a specific series of interactions is known as a type 1a supernova. Because of the steps required to reach supernova status, the brightness of these type 1a supernovae has been considered to be a constant that can be used to estimate distances to very distant galaxies. Brightness declines with distance in a very precise manner.

There remains the possibility that acceleration of very distant bodies in our universe away from each other is a basic property of our space-time structure not detectable at smaller distances of only millions or even tens of millions of light-years, that “dark energy” is just an attempt to recast a phenomenon into understandable terms, just as the caloric theory of heat was long ago. -HK

The measurements of these supernovae were the reason to believe that the expansion of the universe was accelerating. We are seeing these very distant supernovae with light that started its journey over ten billion years ago when the universe was very young. Dr. Milne has discovered that type 1a supernovae are not all the same but fall into two categories of different brightness. Furthermore, the supernovae from the early universe are, on average, less bright than those in the more recent universe.

The lower brightness of the distant supernovae may well be due to less inherent brightness instead of greater distance. This finding destroys a fair piece of that Nobel Prize discovery. Dr. Milne still attests that the universe’s expansion is accelerating, just not so fast, but the vast number of recalculations being done to account for this new discovery will take some time.  Continue reading

Digital Privacy, ELL, Smartphones and GPA, Language and Smell

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Bill Would Limit Use of Student Data by Natasha Singer in the New York Times, 22 Mar. 2015
Singer looks at some of the issues raised by the Student Digital Privacy and Parental Rights Act, a bill to place limits on how “companies that operate school services — like online homework portals, digital grade books for teachers or student email programs —” can use or disclose “students’ personal information to tailor advertisements to them” and “bar them from collecting or using student data to create marketing profiles.”

Digital curriculum targets ELL learning gap from eSchool News, 19 Mar. 2015
Middlebury Interactive Languages has developed English Language Learner programs which “are modeled after Middlebury Interactive’s world language courses and, like those programs, integrate research-based learning techniques, cultural awareness and project-based activities into blended learning classrooms.”

Increased Smartphone Use Equals Lower GPA Among College Students by Brian Heaton from from Government Technology, 17 Mar. 2015
This study from Kent State University about the effects of smartphone use on grades is sure to cause a stir. Even controlling for certain “known predictors, the group still found the relationship between cellphone use and GPA was ‘statistically significant and negative.’”

Does speaking English limit our sense of SMELL? The ability to identify and describe odours depends on the language you speak by Richard Gray for Mail Online, 30 Mar. 2015
While this article is not technology and educated related, it does look at the science of language from a different perspective as researchers describe the relationship between the language we speak and our sense of smell and our perception of colors.

Robots in Movies

picture of Harry KellerBy Harry Keller
Editor, Science Education

Artificial intelligence has appeared in a great many movies over the years, often as robots. The latest is Chappie, a movie that has been panned by a majority of critics but apparently enjoyed by quite a few movie goers.

Robots (or AI) have been good and bad. The first that I recall was Robby in the first science fiction (SF) movie to adhere to scientific ideas (of the time), Forbidden Planet. This 1956 movie starred Leslie Nielsen when he was still doing romantic leading roles. The character of Robby created quite a stir at the time. He was definitely a benevolent robot who was unable to harm humans. An immense computer system, the hidden evil element of the movie, served as a foil.

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Most people remember HAL, the AI embedded in the spaceship of 2001, a Space Odyssey. This movie debuted twelve years later and showed how AI could be a force of evil. Few who saw it will forget the creepy voice of HAL (notably one letter apiece short of IBM alphabetically).

I probably will not see Chappie for several reasons based on the reviews and my viewing of the trailers. The concept of artificial intelligence rising to the level of human consciousness bothers me, not for religious but for scientific reasons. However, many students probably will see it if only because of its themes involving street gangs and defiance of authority.  Continue reading

Videos on Demand: Education Week ‘Leaders to Learn From’ 2015

On 18 March 2015, Education Week recognized 16 exceptional district-level leaders at an exclusive event in Washington, D.C., featuring presentations and discussions on leadership and education policy. Featured speakers included Assistant Secretary, U.S. Department of Education Deborah S. Delisle and Adviser to the Premier and Minister of Education in Ontario, Canada Michael Fullan. Watch the videos from the event.

Recognition Presentation: Meet the Leaders To Learn From (Part I)


Recognition Presentation: Meet the Leaders To Learn From (Part II)

Continue reading

‘Peer Reviewing in Political Science’ – April 2015 Issue of PS

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In The Profession section of its April 2015 (v48, 02) issue, PS: Political Science & Politics (PS)1 scrutinizes the peer review system, a core value in the research community. Some question whether or not peer review is sustainable given the increased and unequal burdens placed on reviewers. In “Peer Reviewing in Political Science: New Survey Results”, Paul Djupe of Denison University argues that the common perception that reviewers are overburdened with requests has never been tested through reliable data collection. He finds, contrary to the conventional wisdom, that most scholars appreciate peer review, and that most peer review requests by journals are accepted. The only common complaint is that peer review is not considered as part of the tenure and promotion process.

Also in The Profession, the right time for associate professors to go for promotion is considered by Kurt Weyland of the University of Texas in “The Logic of the Promotion Decision: In Dubio Pro Patientia”. Weyland argues that it is in the associate professor’s own interest to establish a convincing case before they bid for the rank of full professor and efforts to ‘force’ a promotion prematurely can leave a bad impression and damage the career. Accumulating a strong record in research and publication is the best way to assure a smooth path to tenure.

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In the Profession Symposium, see the articles on “Reinventing the Scholarly Conference: Reflections from the Field.”

In The Teacher , Matthew Woessner of Penn State shows how computer games like SimCity can be used to engage young people to think about politics, governance, and the challenges of managing cities in the real world.  Continue reading

Dark Matter Clues

picture of Harry KellerBy Harry Keller
Editor, Science Education

You may have seen the headlines already. “What is dark matter made of? Galaxy cluster collisions offer clues,” shouts the Christian Science Monitor.1

Here you have a great moment to engage students in something exciting and to use critical thinking. Dark matter is a hypothesis to explain why stars in galaxies circle around their centers faster than the observable matter says that they should, as well as other more sophisticated reasons. It’s called “dark” because it does not emit light and because you cannot see it. You might also have called it “invisible” matter, but much matter seems invisible. Besides, “dark” implies spooky, and this stuff is definitely spooky because ordinary matter moves right through it as though it isn’t there, except for gravitational effects.

The new finding just reported tell us that dark matter behaves just the same way with itself. One patch of dark matter moves right through another as though it’s not there at all (again, except for gravitational effects). This result pushes back against the most popular idea about the identity of dark matter, that it’s WIMPs — weakly interacting massive particles — because particles don’t just pass right through each other.

Dark matter is invisible. Based on the effect of gravitational lensing, a ring of dark matter has been detected in this image of a galaxy cluster (CL0024+17) and has been represented in blue. NASA, ESA, M.J. Jee and H. Ford (Johns Hopkins University)

Dark matter is invisible. Based on the effect of gravitational lensing, a ring of dark matter has been detected in this image of a galaxy cluster (CL0024+17) and has been represented in blue. Image from NASA, ESA, M.J. Jee and H. Ford (Johns Hopkins University).

Two explanations come to mind. Some physicists doing the work still are seeking particles, but these other explanations could help get around that barrier. There are some truly exotic explanations going around as well, such as the existence of a “mirror universe.” It’s best to stick with the simplest ones, though. Occam’s Razor tells us so.

One explanation is that gravity just doesn’t work exactly as we expect it to, especially when dealing with very large masses spanning very large volumes of space. This is not a very popular explanation. The other is that dark matter is really energy. Because of the equivalence of energy and matter demonstrated by Einstein and captured in his famous equation, E=mc2, energy is affected by and causes gravity.  Continue reading

2015 Contest to Promote STEM Innovation in Public Middle Schools: Apply May 4-June 12

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Northrop Grumman Foundation today announced it is launching an online contest to encourage today’s students to become tomorrow’s innovators by creating classrooms and science labs that inspire. The Fab School Labs contest is open to public middle schools and will make five grants of up to $100,000 available to five winning schools to fund a school lab makeover.

Northrop Grumman Foundation Launches Middle School Contest to Promote STEM Innovation

Beginning May 4 and continuing through June 12, 2015, teachers, principals and school administrators can enter their eligible school by visiting www.FabSchoolLabs.com, where they can learn about the contest and submit their application, along with photos and video to help tell their story. Semi-finalist schools will be chosen and their videos will receive online votes of support to assist with the final selection process. The winning schools will team up with Fab School Labs contest partner Flinn Scientific Inc. to design a state-of-the-art lab complete with all of the tools, resources and furnishings needed.

Fab School Labs contest gives schools funding to create a first-class STEM learning environment

The contest is designed to drive students’ interest in science, technology, engineering and mathematics (STEM) by giving public middle school teachers and school administrators the chance to create the STEM lab of their dreams and give students access to the latest learning tools and technologies that will stimulate as well as teach.  Continue reading

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