Tag Archives: science explained

Gravity and the Scientific Method

One of the topics I return to repeatedly is the scientific method – theories must to tested. As evidence mounts that new ideas do a good job of explaining theories they become more accepted. But they continue to be tested in new ways as the ideas are extended and ramification are explored. And science progress means that old conventions can be overturned as new evidence is gathered.

Science is not about current beliefs. Science is about seeking knowledge. If the search for knowledge leads to evidence that old ideas were wrong those ideas are overturned. Since people are involved that process isn’t as clean as it sounds above. People get comfortable with beliefs. They build careers on expanding those beliefs. Most are uncomfortable when they are challenged and don’t accept new ideas even when the evidence mounts. But some do accept the new ideas. Some challenge the new ideas by running experiments. And some of those prove the new ideas faulty. Some become convinced of the new ideas as the results of their experiments make the new ideas seem more sensible (instead of getting the results they expected).

Building the body of scientific knowledge is not nearly as clean and simple as most people think. It isn’t a simple process, what is the underlying truth can be debatable. But the beauty of the scientific process is how it helps us overcome our biases and provide evidence to support the theories we support. The scientific method (combined with our human involvement) doesn’t mean new ideas are accepted easily but it does mean new ideas compete on the basis of evidence not just the power of those that hold the beliefs.

Is gravity not actually a force? Forcing theory to meet experiments
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Ten Things Everyone Should Know About Science

As the writer of this blog (which is located at engineering.curiouscatblog.net) I am a strong believer in the importance of scientific literacy. Neil Degrasse Tyson stated the importance very well, as I mentioned in a previous post, the scientifically literate see a different world

If you are scientifically literate the world looks very different to you. Its not just a lot of mysterious things happening. There is a lot we understand out there. And that understanding empowers you to, first, not be taken advantage of by others who do understand it. And second there are issues that confront society that have science as their foundation. If you are scientifically illiterate, in a way, you are disenfranchising yourself from the democratic process, and you don’t even know it.

The Financial Times has complied a list of the 10 things everyone should know about science

Evolution – previous posts: Evolution is Fundamental to Science – posts tagged: evolution
Genes and DNA – tags: genes – genetics – DNA – RNA
Big bang – tags: physics, posts mentioning big bang
Relativity – General Relativity Einstein/Essen Anniversary Test – posts mentioning relativity
Quantum mechanics – Quantum Mechanics Made Relatively Simple Podcasts, Quantum mechanics
Radiation
Atoms and nuclear reactions
Molecules and chemical reactions – posts on chemistry
Digital data – I must admit, even reading their comments, I don’t understand what they are thinking here. There certainly is a great deal of digital data and the future certainly going to involve a great deal more, but this just doesn’t fit, in my opinion.
Statistical significance – Seeing Patterns Where None Exists, Statistics Insights for Scientists and Engineers, Correlation is Not Causation post on statistics – experimentation

It is a challenge to create such a list. I agree with most of what they have. I would like to look at changing the last 2 and radiation, though. I would probably include something about the scientific method rather than statistical significance. Another area I would consider is something about bacteria and/or viruses. You can maybe include them under genes, but viruses and bacteria are amazing in the very strange things they do with genes and I think that is worthy of its own item. Another possibility is thinking of separating out a second spot for things related to the scientific method – causation, randomized testing, multivariate experiments… I would also consider one, or more of the following or something related to them biology – chlorophyll, the the life of bacteria in our bodies, something related to human health (how drugs work, medical studies…), etc..

The Ten Things Everyone Should Know About Science

Evolution through natural selection remains as valid today as it was 150 years ago when expressed with great elegance by Charles Darwin in The Origin of Species. The mechanism of evolution depends on the fact that tiny hereditable changes take place the whole time in all organisms, from microbes to people.
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An important feature of Darwinian evolution is that it operates at the level of the individual. There is no mechanism for natural selection to change the species as a whole, other than through the accumulation of changes that lead to the survival of the fittest individuals.

The rate of evolution varies enormously between different types of organism and different environmental circumstances. It can proceed very quickly when the pressure is great, as, for example, with bacteria exposed to antibiotics, when drug-resistant mutations may arise and spread through the bacterial population within months.

Why does it matter? Evolution is coming under renewed assault, particularly in the US, from fundamentalist Christians who want creationism to be taught in schools. Although evolution has had virtually unanimous support from professional scientists for at least a century, polls show that American public opinion still favours creationism.

Naturally Curious Children

I write this blog because when I was a kid I was curious and had parents who gave me enough interesting answers and interesting resources to build on that curiosity. And I am still curious today. I love learning. And I love to hear about kids learning.

The Big Girl has worked out evolution

She was ecstatic when we ended up with a rooster in our ‘sexed’ chickens even though Mummy and Daddy weren’t too impressed, because she wants more little fluffy chicks. I think that counts as evidence she knows you need boys and girls to get babies.
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“What would happen if there were no boys?” This is the question she came out with the other day.

“Well, there would be no babies.” I didn’t quite get the problem seeing we were feeding the rather prolific guinea pigs at the time and we’ve been talking about separating them.
“But what if there were no boys at all? So no-one could have babies?”
“Eventually, they would all die.”
“But there wouldn’t be any left!”
“No, they would die out.”
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“How did humans start?”… a puzzled little crease in her forehead. “Because if there weren’t any around with the dinosaurs they must have started sometime. How could there be no humans and then they’re there? What was the Mummy?”
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“Well, they weren’t sudden. You know how you are a little bit different to Mummy and Daddy? That’s how it happened. The babies were just a little bit different to their parents and over a really, really long time they became people.”
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“But if there was only one it would die out.”
Well that came out of nowhere, did I miss half of this conversation?
“You know, the first person. It needs to have both a boy and a girl to have more people babies. So if there was only one it would die out.”
“Oh, from yesterday. Yes, you’re right. But people live in groups, so they’re all changing a tiny little bit at the same time.”

It is great to see developing minds at work. Exploring their natural curiosity. And taking in new information puzzling it out over time and then coming back to the ideas. This kind of curiosity is what drives learning and success.

Driver Thanks Engineer Who Hit Him on Purpose

Driver thanks man who hit him on purpose

Driving to a Mariners game, Duane Innes saw a pickup ahead of him drift across lanes of traffic, sideswipe a concrete barrier and continue forward on the inside shoulder at about 40 mph. A manager of Boeing’s F22 fighter-jet program [and engineer by training], Innes dodged the truck, then looked back to see that the driver was slumped over the wheel. He knew a busy intersection was just ahead, and he had to act fast.
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“Basic physics: If I could get in front of him and let him hit me, the delta difference in speed would just be a few miles an hour, and we could slow down together,” Innes explained. So he pulled in front of the pickup, allowed it to rear-end his minivan and brought both vehicles safely to a stop in the pull-off lane.
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Some might say the driver of the truck, 80-year-old Bill Pace, of Bellevue, and anyone Pace’s truck might have slammed into had luck on their side that day. A retiree who volunteers for Special Olympics and organizes food drives, Pace didn’t know it at the time, but he’d had a minor heart attack two days earlier and his circulation was so poor he passed out at the wheel with his foot resting on the accelerator.

Nice story and nice that the article had a tiny bit of science in the story, with another example of good work by an engineer.

Science and Optical Illusions

More illusions by R Beau Lotto, lecturer in neuroscience, University College London

The middle tiles on the cube both have the same color, even though they appear very different to most of us.

The science of optical illusions

the two physically identical tiles do indeed now look very different.
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Why? The information in the image strongly suggests that the dark brown tile on the top now means a poorly reflective surface under bright light, whereas the bright orange one at the side means a highly reflective surface in shadow.
… [from another illusion]
So why do they look so different? Because your brain takes the image on the retina and creates what it sees according to what the information would have meant in the brain’s past experience of interacting with the world.

In this case the angles suggest depth and perspective and the brain believes the green table is longer than it is while the red table appears squarer.

The beautiful thing about illusions is they make us realise things are never what they seem, and that our experiences of the world shape our understanding of it.

Studying illusions can teach us several things. We can learn that it is easy for our senses to be fooled. We can learn about how the brain works. We can also learn how to take into account how our brain works to try and adjust our opinions (to be careful we are not just interpreting things incorrectly). It is amazing to see some of the wild guidance our brains give us. Normally they do a fantastic job of guiding us through our day but they have weaknesses that can lead us to mistaken conclusions.

Monarch Butterflies Use Medicinal Plants

Monarch butterflies eat toxic plants (that they have evolved to tolerate and make the butterflies themselves toxic to predators). They use medicinal plants to treat their offspring for disease, research by Emory biologists shows. When the butterflies are infected by certain parasites the butterflies have a strong preference to lay their eggs on a plant (tropical milkweed) that will help the caterpillar fight the parasite when it eats those leaves (it serves as a drug for them). Their experiments may be the best evidence to date that animals use medication.

Friday Fun: Aerodynamics for Sports

“Impossible” Soccer Kick Leads to New Physics Equation

The amazing goal — which left French goalkeeper Fabien Barthez too stunned to react — was scored during a friendly match in the run up to the 1998 World Cup. A group of French scientists, perhaps desperate to prove that at least the laws of physics weren’t actively rooting against their national team, have been able to figure out the trajectory of the ball and, with it, an equation to describe its unusual path.
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It all comes down to the fact that, when a sphere spins, its trajectory is a spiral. Usually, gravity and the relatively short distance the ball travels cover up this spiral trajectory, but Carlos was a mere 115 feet away and kicked the ball hard enough to reveal its true spiral-like path.

In this open access paper, the spinning ball spiral, the authors explore the science behind ball paths in different situations.

one can identify sports dominated by aerodynamics (table tennis, golf and tennis) and sports dominated by gravity (basketball and handball). In between, we find sports where both gravity and aerodynamics play a comparable role (soccer, volleyball and baseball). Indeed, in the first category of sports, the spin is systematically used, while it is not relevant in the second category, and it only appears occasionally in the third one, in order to produce surprising trajectories.

The Mystery of Empty Space

Get ready to re-think your ideas of reality. Join UCSD physicist Kim Griest as he takes you on a fascinating excursion, addressing some of the massive efforts and tantalizing bits of evidence which suggest that what goes on in empty space determines the properties of the three-dimensional existence we know and love, and discusses how that reality may be but the wiggling of strings from other dimensions.

Volleyball Sized Hail

photo of volleyball sized hail

On July 23, 2010, a severe thunderstorm struck Vivian, South Dakota, USA, a quiet rural community of less than 200. While there was nothing unusual about a violent summer storm, the softball (and larger)-sized hail that accompanied it was extraordinary. In fact, it led to the discovery of the largest hailstone ever recorded in the United States.

Once the thunderstorm passed, Vivian resident Les Scott ventured outside to see if there was any damage as a result of the storm. He was surprised to see a tremendous number of large hailstones on the ground, including one about the size of a volleyball. Scott gathered up that stone, along with a few smaller ones, and placed them in his freezer.

How does hail form?

Inside of a thunderstorm are strong updrafts of warm air and downdrafts of cold air.
If a water droplet is picked up by the updrafts…it can be carried well into colder zones and the water droplet freezes.
As the frozen droplet begins to fall, carried by cold downdrafts, it may partially thaw as it moves into warmer air toward the bottom of the thunderstorm
But, if the little half-frozen droplet get picked up again by another updraft and is carried back into very cold air it will re-freeze. With each trip above and below the freezing level our frozen droplet adds another layer of ice.
Finally, the frozen hail, with many layers of ice, much like the rings in a tree falls to the ground.

According to NOAA, the Kansas City hail storm on April 10, 2001 was the costliest hail storm in the U.S. which caused damages of an estimated $2 billion.

Image from NOAA

Parasites in the Gut Help Develop a Healthy Immune System

It has long been known that microbes in the gut help to develop a healthy immune system, hence the rise in popularity of probiotic yoghurts that encourage ‘friendly’ bacteria. But new research by Professors Richard Grencis and Ian Roberts shows that larger organisms such as parasitic worms are also essential in maintaining our bodily ‘ecosystem’. “The worms have been with us throughout our evolution and their presence, along with bacteria, in the ecosystem of the gut is important in the development of a functional immune system.”

Parasite Rex is a great book, I have written about previously looking at parasites and their affect on human health.

Professor Grencis adds: “If you look at the incidence of parasitic worm infection and compare it to the incidence of auto-immune disease and allergy, where the body’s immune system over-reacts and causes damage, they have little overlap. Clean places in the West, where parasites are eradicated, see problems caused by overactive immune systems. In the developing world, there is more parasitic worm infection but less auto-immune and allergic problems.

“We are not suggesting that people deliberately infect themselves with parasitic worms but we are saying that these larger pathogens make things that help our immune system. We have evolved with both the bugs and the worms and there are consequences of that interaction, so they are important to the development of our immune system.”

Whipworm, also known as Trichuris, is a very common type of parasitic worm and infects many species of animals including millions of humans. It has also been with us and animals throughout evolution. The parasites live in the large intestine, the very site containing the bulk of the intestinal bacteria.

Heavy infections of whipworm can cause bloody diarrhoea, with long-standing blood loss leading to iron-deficiency anaemia, and even rectal prolapse. But light infections have relatively few symptoms.
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