Stories tagged Forces of Nature

Nov
19
2007

Garrett Lisi, a 39-year-old surfer, hiking guide and construction worker (with a PhD in theoretical physics), believes he may have solved the biggest problem in all of science – how are all the particles of matter and forces of nature related to one another? Scientists since Einstein have been trying to figure it out, with little success. (The current theory involves outrageously tiny “strings” vibrating in 11-dimensional space. The mathematics, they say, is beautiful, but it cannot be tested or verified.) Lisi’s breakthrough came when he noticed that the formulas that describe something called the E8 pattern -- a complex, geometrical design with 248 points – also describe many of the fundamental forces and particles. His theory is that nature follows the same formulas as E8, and that the figure can be used to predict particles that have not yet been discovered. If he's right, he will have finally shown that everything in the universe is related, and basically just different manifestations of the same essence.

Rad, dude.

Aug
10
2007

A wild tornado searches for prey: If only we could tame them!  (image courtesy of the NOAA photo library)
A wild tornado searches for prey: If only we could tame them! (image courtesy of the NOAA photo library)
Techno-magician Louis Michaud believes that he can summon a tornado, “tame” it, and use the entity to generate electricity. And he intends not to simply summon a miniature steam vortex, such as can be seen in the Science Museum of Magisota’s Experiment Gallery, but a full-sized wind monster, as featured in the documentary “Twister.”

As bizarre as the idea might seem, councils of air and wind magicians at learning institutions across the country say the theory is sound. It would simply require a sorcerer of the most audacious kind. Perhaps the wizard Michaud is just that person.

The idea is based on the simple and well-known principle that tornado beasts feed and grow off of warm air. Michaud proposes summoning the tornado into a “vortex engine” using a source of hot air such as the waste heat from a nearby nuclear generator (or even, depending on geography, heat from warm tropical water). The hot air would be directed up from the vortex engine’s base in a spinning motion, and would gather momentum as it rose, eventually becoming a tornado several kilometers high. The air sucked into the tornado would spin turbines and generate electricity. The normally chaotic and destructive tornado beast would be content to stay above the vortex engine, feeding off the hot air provided. The wizard Michaud also claims that the stationary, summoned tornados could have the added benefit of combating, in some small way, the powers of That-Which-Shall-Not-Be-Named (Global Warming, as it likes to be called). The vortex engines would propel hot air high into the atmosphere, where it could more easily radiate energy back into space – an interesting idea, although it seems like there would have to be countless such tornado summoning stations to have any measurable effect. Who’s to say?

However, there is a price to pay for all this, as is always the case with magic. While universities have been experimenting with the summoning spell on a small scale – luring tornados not larger that a meter or two into this realm – the facilities for commercial-scale summoning would cost somewhere on the order of $60 million. This price would be offset somewhat if the generator were built in conjunction with a nuclear power station, as the station would no longer need a $20 million cooling tower. Michaud has formed the corporation AVEtec to seek investor funding. High wizards from Oxford, Cambridge, and MIT have joined AVEtec’s advisory board.

Those of you less experienced in the magical arts might be well served by this article, or this one, both of which offer a more scientific perspective.

Aug
02
2007

Vibration problem?: A combination of vibrations coming from various area sources could be factors in the fall of the I-35W bridge in Minneapolis on Aug. 1. (Flickr.com photo by Diversey)
Vibration problem?: A combination of vibrations coming from various area sources could be factors in the fall of the I-35W bridge in Minneapolis on Aug. 1. (Flickr.com photo by Diversey)
tangled roadwayI’m not a structural engineer and don’t even play one on TV, but I’m curious to see what kind of dots get connected on this scientific phenomenon and the I-35W bridge collapse.

A former chairman of the National Transportation Safety Board, who just happened to be in the Twin Cities the day of the bridge collapse, raised some interesting questions. Jim Burnett was interviewed by the Star Tribune today and said that bridge collapses usually have two main causes: vibration and fatigue cracking.

Earlier inspections of the bridge have noted that it showed signs of fatigue cracking, but not to the degree that officials felt the bridge needed immediate attention. But I haven’t heard a lot of comment in press accounts, yet, about vibration. Burnett pointed out that two primary causes of vibration were going on or near the bridge at the time of the collapse: construction work on the bridge’s road deck and also vibrations from a train passing underneath it.

“Vibration is one of things that cause cracking to propagate," he said to the newspaper. "They will be looking at that."

He was on the scene of the collapse at 5 a.m. today (Aug. 2) before sharing his preliminary thoughts on the collapse. But his analysis got me thinking to the role vibrations have played in other bridge failures.

Remember the Hyatt Regency hotel walkway failures in Kansas City in 1981? About 2,000 people were there for a dance contest. The hotel featured several walkways suspended at the second, third and fourth levels over the hotel’s atrium. When people started dancing on the walkways, the vibration of the feet moving together caused them to collapse, killing 114 people and injuring more than 200 others.UPDATE: See the comments below for clarification on the Kansas Hyatt disaster.

Digging around a little more, I found these postings by engineers at the Ask a Scientist website.

Here’s some observations from engineer Vance Calder: An army troop marching at full cadence is ordered to stop marching and walk across a bridge at each soldier’s own individual gait. The "in time" stepping produces vibration, the multitude of soldiers adding to the vibration. When trying to think of waves, think of waves in water. Opposing waves can cancel each other. But like the troops moving in the same direction, the waves can add to each other and gain extra strength.

More points from engineer James Prxewoznik include: Vibration, in general, is bad for materials. It can lead to fatigue of parts and eventual failure. There are two types of vibration: free vibration and forced vibration. Free vibration occurs through actions of forces inherent with its design. Forced vibrations come from external forces outside the design of an object. If those two forces coincide, the vibration oscillations can magnify causing an object to come apart.

There might have been a lot of vibration at play on the 35W bridge: jack-hammering and other construction work, the train passing underneath, and don’t forget, it was an extremely windy day in Minneapolis on Aug. 1. A lot more needs to be checked out, of course. But investigators will likely be looking at how many different forms of vibration combined on the bridge at the time of its collapse.

Jun
11
2007

Wind farms produce clean energy, but some people consider them eyesores: Photo by fieldsbh at Flickr.com
Wind farms produce clean energy, but some people consider them eyesores: Photo by fieldsbh at Flickr.com

A new book, Cape Wind: Money, Celebrity, Class, Politics, and the Battle for Our Energy Future on Nantucket Sound, tells the story of efforts to build wind turbines off the coast of Cape Cod to provide clean, renewable energy for the state of Massachusetts. However, some of the wealthy people who live in the area – including some renowned environmentalists – object to the project located so close to their own homes.

This article from the Cape Cod Times describes some of the legal maneuvering that has thus far blocked the project. One objection is that wind turbines kill migrating birds. The reporter did some research and came up with the following statistics:

Human-caused bird deaths

• Domestic cats: Hundreds of millions a year
• Striking high-tension lines: 130 million - 1 billion a year
• Striking buildings: 97 million to 976 million a year
• Cars: 80 million a year
• Toxic chemicals: 72 million
• Striking communications towers: 4 to 50 million a year
• Wind turbines: 20,000 to 37,000

Source: National Research Council

Clearly, turbines are not a major threat to birds, while the clean energy they provide would be a major boost to the environment. So why are some environmentalists opposed? The authors of the book say it’s because the turbines, several miles off the coast, would still be visible from their beach-front property. (It is also interesting to note that some of the anti-turbine legislation has been proposed by congressmen from states that just happen to produce a lot of coal.)

For an overview of the issue, read this article from The Boston Phoenix.

May
18
2007

Burning out: The forest fires of today lead to the forests of tomorrow. The heat and pressure of the fire explodes cones filled with seeds that start the growth of a new forest days after the fire has stopped. (Photo from the US Department of the Interior)
Burning out: The forest fires of today lead to the forests of tomorrow. The heat and pressure of the fire explodes cones filled with seeds that start the growth of a new forest days after the fire has stopped. (Photo from the US Department of the Interior)
The recent forest fires in the northern Minnesota have scorched a huge chunk of the Superior National Forest. But they’re also the beginning of the next generation of huge trees to grow in the wild.

Even as the fires were crackling through the branches of pines, birch and spruce, the start of new tree growth was already popping. The heat from the burning trees pops open the cones on those trees, releasing seeds that have been waiting to get loose for years. Millions of those seeds were dumped on the forest floor and within less than a month, a fraction of those seeds to germinate, pop through the soil and start growing into little seedlings. Give them another 30 or 40 years, and hikers going through the area where this year’s fires have wiped out most trees, those seedlings will have grown tall enough that hikers won’t even know the area had been devastated by fires in 2007.

In fact, fire is a natural part of the forest’s regeneration system. Most forest trees need to be exposed to fire every 50 to 100 years to invigorate new growth. As we found out in Yellowstone National Park nearly 20 years ago, suppressing forest fires too long can actually be detrimental to forests. Extreme efforts to prevent forest fires there led to a huge consumption of trees when fire finally broke out.

University of Minnesota-Duluth biology professor John Pastor was quoted this week in the Star Tribune saying: “When people canoe through the Boundary Waters Canoe Area (BWCA) and see all these beautiful forests, every one of those forests started with a fire.”

As a rule of thumb, timber experts say that any particular chunk of ground in the forest should be touched by intense fire every 50 to 100 years.

But the power of the fire is just the first step in forest regrowth. Weather patterns in the affected area over the nest year will play a big role in how the new forests develop. A summer of drought could kill the newly released seeds and short-circuit any new growth. That could give new species of trees a chance to grow in the area. Normal rains mixed with the nutrients left on the ground from the fire could be a great booster shot to getting the seeds off to a flying start.

Other natural benefits can be seen from fires. For instance, the once-rare black-backed woodpecker is now a regular site in the BWCA with the abundance of dead trees from recent smaller fires and the 1999 wind blow down of trees. New shrubs and ground vegetation is appealing to different kinds of wildlife to snack on.

Apr
18
2007

Ever wanted to be a storm spotter? Now's your chance! The National Weather Service (NWS) relies on local SKYWARN storm spotters to confirm, from the ground, what meteorologists are seeing on radar. NWS storm spotters are not tornado chasers like the folks in the movie "Twister." Instead, they report wind gusts, hail size, rainfall, cloud formations, and the like to NWS and local emergency management agencies.

Tornado: This tornado, seen in its early stages of formation over Union City, Oklahoma (May 24, 1973), was the first one caught by the National Severe Storms Laboratory doppler radar and chase personnel. (Photo courtesy NOAA Photo Library, NOAA Central Library; OA
Tornado: This tornado, seen in its early stages of formation over Union City, Oklahoma (May 24, 1973), was the first one caught by the National Severe Storms Laboratory doppler radar and chase personnel. (Photo courtesy NOAA Photo Library, NOAA Central Library; OA

New radar equipment is still not sensitive enough to determine the existence of an actual tornado. It can only predict where severe weather is likely to occur. So the NWS needs trained volunteers to verify actual severe weather.

With peak storm season just around the corner (mid-June here in the Upper Midwest), free, 2.5-hour classes are being offered to train new SkyWarn volunteers.

SkyWarn class schedule, greater Minnesota
SkyWarn class schedule, Twin Cities Metro area

Here's how you get started...

Apr
03
2007

The 2007 Atlantic hurricane season officially begins June 1 and runs through November 30.

Two hurricanes: This satellite image, captured 8/30/05, shows Hurricane Iris in the central Atlantic Ocean, with Tropical Storm Karen to the southeast. (The original image, from which this is cropped, also showed Hurricane Humberto moving northeast across the Atlantic.)
Two hurricanes: This satellite image, captured 8/30/05, shows Hurricane Iris in the central Atlantic Ocean, with Tropical Storm Karen to the southeast. (The original image, from which this is cropped, also showed Hurricane Humberto moving northeast across the Atlantic.)

Check back often for the latest predictions, forecasts, and discussion.

Mar
23
2007

The real cause of climate change?: A new film argues that the Sun, not people, is driving global warming.  Photo by NASA.
The real cause of climate change?: A new film argues that the Sun, not people, is driving global warming. Photo by NASA.

An earlier thread discussed the movie An Inconvenient Truth. Now, a British television network has produced a documentary of its own, entitled The Great Global Warming Swindle. (Streaming video; one hour and 13 minutes.) The film interviews many top scientists who disagree with the theory that human-produced CO2 causes global warming. It offers compelling evidence that climate change is driven by the Sun. And it ends with a rather disturbing look at how science and politics have influenced each other, with potentially dire consequences.

Regardless of how you feel about climate change and global warming, it's worth watching to film, to hear another side of the debate.

Mar
12
2007

This summer will mark the 40th anniversary of Loving vs. Virginia, a United States Supreme Court decision which declared state laws against inter-racial marriage were unconstitutional. In 1967, inter-racial marriages were illegal in 27 states, and comprised only 2% of all marriages. Today, 7.5% of marriages are inter-racial. Experts cite two reasons for this increase:

1) thanks largely to immigration, the US is a more diverse country today than it was 40 years ago. People of different races have a much higher chance of meeting and falling in love.

2) There has been a trend toward marrying later in life. An adult in their 30s or 40s is less likely to submit to parental pressure than someone in their early 20s.

All this has led to a great change in attitudes. In 1972, some 39% of Americans still felt there should be laws against inter-racial marriages. 30 years later, that had shrunk to 10%, and was even smaller among young people, meaning this taboo is clearly fading from American life.

Feb
12
2007

Shake it up

Bridge shaking experiment
Bridge shaking experiment
Want to see what happens to a bridge during an 8.0 magnitude earthquake? Huge "shake tables" help engineers understand the impact of earthquake forces on bridges and other construction.

You can watch

This Thursday (Feb 15) at 10 am Reno, Nevada time, a quarter scale, 110 ft., 4 span bridge section will be shaken by forces twice the intensity of the 1994 Northridge earthquake.

The Network for Earthquake Engineering Simulation (NEES) website has provided links to a variety of resources: