Stand back I’m doing science!

Percolating Thoughts

Some various thoughts that flow from one to the next:

  1. A PhD candidate in ecology once told me that he didn’t understand how people gained weight from calories. “Isn’t it just energy?” It was a rather startling reminder of just how stratified different fields of science are. I explained that extra energy is stored as fat in the body.
  2. I was listening to a Star Talk Radio episode during my run yesterday and they talked about how you have to have an energy source to make a starship start flying (that is, to overcome the pull of gravity). So I started trying to work out the science of exercise in my head.
  3. I’ve been slowly trying to understand eating for fitness. It’s pretty sad that I’m most comfortable with eating for weight loss, not for supporting physical fitness (though there are definite huge overlaps, since I don’t believe in unsustainable diets).
  4. I had one of those, “Oh wow, evolution is beautiful” moments this morning. Here’s what hit me: Our body is designed to quickly and easily provide that energy we need to overcome inertia/gravity/etc whenever we decide to move. We barely have to think about doing it. This is incredibly basic science, but it was never explained that way in high school. No one ever took our Biology class and our Physics class and said, “Here is a real-life, everyday example that matters for you: do you realize HOW CRAZY IT IS that you can just start walking right now if you want to?” (I could rant for hours about how little of our high school curriculum was made applicable to everyday life, and therefore accessible/relevant enough to really engage us in the subject matter.)
  5. I did a quick Google search and found this website that basically breaks down the whole calories become energy and fat thing and very briefly touches on the Physics of it (the potential energy/kinetic energy that our body uses).
  6. I wonder what the reaction would be if, like in the website above, schools actually taught students how to calculate their calorie needs based on their activity levels. I think it would be tremendously useful and could be done in a healthy way. There is so much misinformation out there, and high school is the perfect age to address it (here’s a really fabulous article about it). We have the information, but it’s getting buried under layers and layers of misinformation and media agendas. And if this isn’t “Biology” and “Physics” and “Chemistry,” then something is wrong with our curriculum.

Epsom Salts

I started CrossFit training this week. It’s amazing and fun and I had difficulty walking for a few days afterwards! So I walked – slowly – to CVS mid-week to buy Epsom salts. My friend asked me if they really work, which made me curious to research how they work. I suspected the salt was just a carrier for some other chemical that gets dissolved in the bathwater.

I thought this would be a quick project, but I got really into the history research! Here’s what I learned.

For those of you inclined to scroll, here’s the layout of this post:

  • What are Epsom salts?
  • How are Epsom salts made?
  • A Brief-ish History of Epsom Salts
  • The Research on Epsom Salts
  • My Conclusions

What are Epsom salts?

Epsom salt is a compound of two naturally occurring chemicals – magnesium and sulfate. Magnesium and sulfate are both chemicals that help your body run smoothly – especially your bones and joints. The idea is that you absorb the magnesium and sulfate through your skin during an Epsom salts bath.

How are Epsom salts made?

The information I found online was really vague, but here is what I was able to figure out/find:

Magnesium and sulfate can both occur in water. The original “epsom spring” is/was in Epsom, England (more on this below). Originally, people used the waters as is; later, they dissolved the spring water to obtain epsom crystals.

According to the EPA, sulfate occurs naturally in our drinking water, but at small doses (high levels of sulfate can be associated with diarrhea. About 3% of US drinking water has the max recommended level of sulfate [the level at which it affects the taste and smell of the water], but sulfate levels are not regulated by the US government).

Magnesium also naturally occurs in drinking water, but at low levels. In fact, there is concern that many or most Americans may be deficient in magnesium, and there’s some push for magnesium to be added in to our drinking water.

So unless you have a naturally occurring spring with high levels of magnesium sulfate, I would venture to guess that most manufacturers today are producing magnesium sulfate in the laboratory and then infusing salts with it. I saw a few references to using Dolomite crystals, which are made up of magnesium and calcium.

If you’re interested in crystal-growing, the easiest thing is to buy some Epsom salts to start with. Dissolve the salt in the hot water and pour it over a rock in a bowl (that’s the surface for your crystals to grow on). As the water evaporates, the salt will re-crystallize. (source)  Alternatively, you can buy a Dolomite rock for crystal growing.

Dolomite crystals. Image courtesy of

Dolomite crystals. Image courtesy of

A Brief History of Epsom Salts

“… medicine sent from Heaven.”
– Nehemiah Grew, “On the Bitter Cathertic Salt in the Epsom Water” (1695)

The original “epsom spring” was in Epsom, England. In the early 1600s, the story goes, some cows refused to drink from the spring. The local people decided that the waters must be medicinal and began using it for open sores, and in 1645 Lord Dudley North published a book promoting the benefits of Epsom waters for open sores, skin conditions and “melancholy”.

Epsom, England is now known for women cheering at the local Derby. Image courtesy of Zimbio.

Epsom, England is now known for women cheering at the local Derby. Image courtesy of Zimbio.

Epsom quickly became a major tourist draw as hundreds – or even thousands, by some accounts – traveled to use the medicinal waters. In 1695, Nehemiah Grew, a physician and member of the Royal Society, published a treatise on Epsom salts. Dr. Grew may have been the first to extract Epsom salts from the water, and he recommended it for a wide array of maladies, including heartburn, poor appetite, colic, diabetes, jaundice, vertigo and many other conditions. He would flavor it with mace, which is still used today as an anesthetic.

By the early 1700s, the external use of epsom salts and waters was established in the “regular” medical profession. (“Regular medicine” was the term for what we now think of as “Western medicine”.) Retailers would boil Epsom water to get the salt crystals. Physicians would prescribe the salts along with instructions for how much water to dissolve them in. Gauze would be soaked in this solution of dissolved Epsom salts and would be applied for twenty-four hours to the affected skin, or patients would drink the solution. Around 1715, subcutaneous – meaning injected under the skin – application of Epsom salts was slowly came into popularity. Applied subcutaneously, Epsom salts were meant to be an anesthetic, relieving pain.

Still in the early 1700s, a Dr. Hoy figured out how to use sea salt to manufacture Epsom salt crystals, driving down prices and raising accusations of bogus imitation medicine.

The Epsom spring remained popular until the mid-1700s, when sea bathing became the newest health fad. Obviously, Epsom salts survived the ages despite the incoming trends.

Sources: Colonel R. D. Rudolf, “The Use of Epsom Salts, Historically Considered” Canadian Medical Association Journal (1917); A. C. Wootton, Chronicles of pharmacy, Volume 1 (1910).

The Research: Do Epsom Salts Really Work?

At first, this question seemed to lead to a lot of dead ends. I couldn’t find any published studies – I found one study that has never been published where the researchers did find increased blood and urine levels of magnesium and sulfate in subjects who took Epsom baths. But I couldn’t find any research on whether absorbing magnesium sulfate is beneficial, or if it needs to be ingested for our bodies to use it.

Since I’ve been seeing a lot in the blogosphere recently about our bodies absorbing chemicals through skin (ie, from using deodorant), I was really bothered by this. Someone had to have looked into it! So I kept looking, and I found a study published in the European Journal for Neutraceutical Research that looked at cellular increases of magnesium using some “magnesium products” (not Epsom salts, but still based on skin absorption). Not only did this study find increased levels of magnesium, but the researchers claim that skin absorpotion might be better than digesting a supplement because the digestion process destroys some of the supplement. The study looked at a really, really small group of people, so it’s hard to say whether the results are really valid. I also can’t be sure that the results apply to Epsom salts.

My Conclusions: Do Epsom Salts Really Work?

The answer is, unfortunately, that I really don’t know. Obviously I’m not a doctor and you shouldn’t take my advice anyway!

It’s honestly hard to say whether we can go on “historical precedent” or anecdotal evidence here. Yes, a lot of people have used Epsom salts for a long time. Hypothetically, if they did nothing for us, we’d have dropped it completely long ago. But human history doesn’t seem to go that way. It’s not so much that we’re good at tricking ourselves as that our bodies do respond to what we expect to feel.

Do Epsom salt baths hurt you? No (unless you use way too much Epsom salts in your bath – follow the package instructions!).

Has it been scientifically proven that they help you? Not really.

So – my conclusion? We need more research. And I would make the argument that it’s worthwhile research. Anything that people are using as a medical therapy should be seriously researched and understood, and it seems that we would additionally benefit from better understanding the ways that our bodies absorb chemicals and nutrients.


I volunteer in an exhibit where visitors can choose from thousands of collection objects to take out, touch, and study. It’s really cool to see kids using microscopes and getting excited about learning.


Above: a girl looking at sparrow eggs.

Since I have a love for macro photography, it’s also fantastic to see the collection objects under the microscope. There are thousands of little details and, often, the most surprising textures or variations that we can’t notice with just our eyes.

I’ve been snatching iPhone photos of many of these over the past few weeks – quick snapshots don’t make for the best photo composition, but I’m going to share them anyway. Unfortunately I didn’t note down what all of them were, but again – I’m going to share them anyway.

This is probably my favorite. Here is the “normal size” version …


And below is the microscope version.


The reason I think this one is so cool – besides just “Look at it, of course it’s amazing!” is that it’s a dinosaur bone.

Really. A dinosaur bone – except that instead of the bone being replaced with stone like fossils frequently are, this one got replaced by the mineral agate.

Here are other photos:



Igneous rock basaltic glass, normal-sized:


And under a microscope:


The shell of a painted snail – that’s its name, “painted snail”:



Above: “normal size” tectosilicate mineral chalcedony. Below, the zoom-in:




Another thing I love – as shown in the photos above – is how you can re-focus the microscope so that different “layers” of an object come more into focus.

A shell:



The wing from a bumblebee (my iPhone somehow turned everything purple?):


The wing from a dragonfly:


A moth:


A morpho butterfly (those circles are pins keeping it in place):



Ivory tree coral:


Gorgeous, aren’t they? Watching the kids use the microscopes and get so enthusiastic makes me want to have a microscope someday at home for my own kids to play with.

Ten Things I Learned About Galileo This Week (that I may or may not have known before)

I’ve been snatching moments to read Galileo’s Daughter by Dava Sobel – a biography of Galileo and his family. I only knew the elementary school basics before, and I’m finding that he was a fascinating man. It’s especially interesting to draw comparisons to today – when our models and ideas of how the world works continue to be upended by new research and calculations.

Below are some of the things I found especially fascinating about Galileo – call it a book report, if you will.

1) Galileo was his first name. I did technically know this before, but it never occurred to me to be curious about it. Why is Galileo known for his first name like Madonna or Cher, instead of his last name like Mozart or Shakespeare or Einstein?

At first I thought that maybe it was a trend of the times. But when I looked up Galileo’s contemporaries, we know them all by their last names: Shakespeare, born the same year as Galileo; Descartes, born about 30 years after Galileo was born (who held off publishing a book of his own on the Copernican system when he heard the verdict of Galileo’s trial); etc, etc. It doesn’t seem to be an Italian thing, either: Machiavelli, for example (incidentally, I learned that both Botticelli and Donatello weren’t the artists’ real names while researching this).

Fortunately, others have wondered this same question and I found a Slate article on the topic. The simple answer is: we call Galileo Galileo because that’s what he chose to be called.

2) Galileo really didn’t mean to be a rebel.

Galileo sincerely believed in Catholicism. He sincerely believed in science. And he believed that because science could never contradict religion, then any discoveries he made only served to illuminate misinterpretations of the Bible. He went out of his way to demonstrate that his theories actually helped to support the Biblical text, in particular the story of Moses asking that the sun hold still. He pointed out that many things in the Bible were not taken literally, and that it would be blasphemous to do so.

It’s worth noting here that many people in the church really thought that Galileo was a wonderful person and scientist.

3) He learned how to be a rebel from his father, as illustrated by this wonderful quote:

“It appears to me, that they who in proof of any assertion rely simply on the weight of authority, without adducing any argument in support of it, act very absurdly. I, on the contrary, wish to be allowed freely to question and freely to answer you without any sort of adulation, as well becomes those who are in search of truth.”

– Vincenzio Galilei, father to Galileo Galilei

To re-state: Galileo believed in the pursuit of knowledge. He believed that this knowledge could only enhance his appreciation of a God-made world, and that to stifle the exploration of science could only support blasphemy.

4) At the same time, Galileo was great at flattery. It helped when you had something he wanted … like the ability to give him an appointment as the Chief Mathematician of the University of Pisa and Philosopher and Mathematician to the Grand Duke:

“Your highness … scarcely have the immortal graces of your soul begun to shine forth on Earth than bright stars offer themselves in the heavens which, like tongues, will speak of and celebrate your most excellent virtues for all time…”

Incidentally, Galileo’s dedication of the moons of Jupiter (as described in the quote above) to the Grand Duke also helped his business, because when other scientists questioned whether these celestial bodies existed at all, Galileo naturally had to supply them with his superior, homemade telescopes – to protect the Grand Duke’s honor.

5) Art and science were far more entwined in Galileo’s time than in the modern day. Part of what fascinates me about Galileo is that all of his great discoveries were simply the result of him following tangents that interested him. His interests led him to invent a compass, improve the telescope, discover the moons of Jupiter, study poetry, develop a compound microscope, design an early thermometer, study how things could float in water, develop a prototype for pendulum clocks and much more.

6) At the same time, Galileo had an uphill battle to use mathematics – his true love – in the world of science.

“I hear my adversaries shouting in my ears that … geometers [mathematicians] should stick to their fantasies and not get entangled in philosophical matters [physical sciences] … as if … anyone who knows geometry cannot know physics, and cannot reason about and deal with physical matters physically!” – Galileo

In Galileo’s time, science was driven by Aristotle’s observations hundreds of years before. To put it even more bluntly: science was driven by observations, period. The idea of using mathematics to support – or even derive – hypotheses was extremely iffy. Aristotelian science pretty much said that Nature was too chaotic to follow mathematical rules. One of the reasons that Galileo was able to gain some credence – and notoriety – advancing Copernicus’ theory of a Sun-centered universe was that Copernicus had only used mathematics. Galileo waited for years after learning Copernicus’s theory that the Earth moved around the Sun so that he could use observations, not just math. He was able to show how what you saw through his telescope paired with his mathematical logic to support his conclusions. This, along with the next item, were partial contributors to Galileo’s run-in with the Church. He also just had bad timing: Copernicus didn’t publish his theories until he was literally on his deathbed, and the Church passed edicts shortly thereafter that essentially outlawed any science that contradicted the Church’s interpretation of the Bible.

7) Galileo believed that education was for laypeople as well as high society.

This was another reason that he had the religious and scientific communities up in arms: he wrote some of his books in Italian instead of Latin – so that everyone could read it, not just scholars. He argued that it was unfair that only those who could afford to attend university had access to knowledge, arguing that laypeople had both, “Eyes with which to see her [Nature’s] works … also … brains capable of penetrating and understanding them.” As one of the Church scholars wrote, “He writes in Italian … to entice to that view common people in whom errors very easily take root.”

Further, Galileo published some of his arguments in the form of a play, poking fun at the opposition by demonstrating (through his characters) that even uneducated peasants could see that his opponents’ arguments were ridiculous.

8) Galileo wasn’t just a mind walking around on top of a body.

Galileo lived in a time when, similar to today, intellectualism was considered its own work if you could afford it. But Galileo enjoyed using his hands as much as his mind. A story goes that Galileo had unexpected visitors one day while he was gardening. Asked why he didn’t hire someone to do the manual labor, he replied, “No, no; I should lose the pleasure. If I thought it as much fun to have things done as it is to do them, I’d be glad to.” He also made sure to use real life applications in his writing. For instance, he explained how a 45-degree angle was optimal for shooting long-distance cannon fire, or how building boats in larger sizes impacted their structural integrity. This drastically changed the tone of physics; instead of trying to explain why things happened, he instead explored how they happened. This changed the focus of physics from 50,000-foot philosophy to on-the-ground, applied research that allowed the natural laws of the world to reveal themselves through their impacts.

He was also very much a family man; he and his daughter exchanged frequent letters and Galileo took on many of the finances for his brother, sisters, and children.

9) Galileo played by the rules. He really did (up until he was condemned by the Church). When the Church said that Copernicus’s theories were unmentionable, he desisted from mentioning them again in his writings until a new Pope was voted in who was more open to it. He carefully floated his ideas past this Pope before proceeding with his writing. When the Church said that he could publish about Copernicus’s theories so long as it was made clear that they were only hypotheses and not facts, he took care to do exactly that. His writing was proofread by the Church itself and approved.

So when Galileo ran into trouble – upon the publication of his Dialogue, which depicted three friends exploring the Ariostotelian and Copernican systems of the universe – it wasn’t because he’d gone behind Rome’s back or published anything without permission. It was simply that the Pope was having a bad month, had been accused of being too lax in enforcing the Catholic faith, and certain advisers counseled him that Galileo’s book was a personal insult.

Now …. did Galileo’s book basically argue that the Copernican approach was correct? Yes. But still – he had gone through all the correct channels to have his book approved and published. It would be inaccurate to say that the Church changed its mind – rather, those who were against Galileo gained the upper hand shortly after the publication of his Dialogue, which was most unfortunate timing.

There is an irony here: as soon as word spread from Rome that Galileo’s Dialogue had been banned, a fierce Black Market trade of the book sprung up. The book became more valuable, and gained both more readers and more “converts” to the Copernican system, inside of and outside of Italy.

The Church didn’t retract its ban on books teaching the Copernican theory until 1757, but the Dialogue remained banned until 1822.

10) Galileo inspired Newton’s laws of motion. Galileo was heartbroken after the Church pronounced him guilty of heresy, but his friends slowly drew him back into his projects. He refocused his energy on a project that he had allowed to lapse for most of his career: studying the laws of motion. The last book Galileo published, Discourses and Mathematical Demonstrations Concerning Two New Sciences, informed Newton’s later ideas on his laws of motion and universal gravitation. Interestingly, Galileo considered Two New Sciences to be his most important work. It nearly wasn’t published; after the Church condemned Galileo, it forbade the printing of any of his books. A Dutch publisher had to covertly visit Galileo to get his manuscript. Galileo later feigned surprise that his Two New Sciences had ever found its way to Holland, and claimed that he had not been informed of the printing until it was already underway.

On a related note, Einstein is quoted as having named Galileo the father of modern physics because of the way that he incorporated mathematics into his approach.

All in all – Galileo’s Daughter is a fascinating book, and I highly recommend it. I’m intrigued to find a book on Vincenzio Viviani when I have the opportunity. Viviani was Galileo’s student and fiercely loyal to him; we have him to thank for much of what we know of Galileo’s life and works, and his family is responsible for the eventual placement of Galileo’s body in its final, honored resting place.

Question from Another: Caterpillars and Butterflies

I get some really great questions from museum visitors. A parent asked me the other week whether caterpillars are classified as a stage in the life of a butterfly, or classified as their own kind of insect.

I didn’t have the answer, but I was curious enough to look it up: Caterpillars are classified under Lepidoptera as the larval stage of butterflies.

It turns out that butterflies live on every continent except Antarctica, and the largest butterflies can be as large as 11 inches across. Most butterflies travel 5 to 10 mph, but skippers can keep pace with a car at 37 mph.

Here’s some more cool info from the San Diego Zoo website:

The caterpillar’s insides grow, but not its outside—when it gets too big for its skin, the covering  splits and is shed. A new exoskeleton lies underneath. A caterpillar sheds its skin 5 times, then becomes a pupa.

The last time the caterpillar sheds, a hard casing called a chrysalis forms around its body. Inside the chrysalis, big changes are happening. The pupa is growing six legs, a proboscis, antennae, and wings. After 10 to 15 days, the chrysalis breaks open and a butterfly emerges. At first its wings are wet and crinkled, but after about an hour, they are straight, dry, and strong enough for the butterfly to flutter away.

If you ever have a chance to go to a butterfly room – several science museums offer them, though it’s sometimes seasonal – it’s a really cool experience. Take a friend; the selfie photos of yourself with a butterfly on your shoulder tend to come out a bit awkward looking :-).

Time Relativity

The Background
I’ve been watching Stephen Hawking’s Into the Universe lately. I highly recommend it, but I also have to give due credit to my friend Jeremy, who spent an hour patiently answering my resulting, increasingly intricate questions about black holes.

Disclaimer #1: Having said that, any misinformation below is entirely my own fault! I purposely insisted on researching this within my limited layperson ability and refused to ask or receive help from several STEM (Science/Tech/Engineering/Math) friends – I wanted to see what I could uncover on my own and just how much the Internet can empower people to learn (though granted part of its power is in enabling people to crowdsource questions). Having said that, Awesome Science People are more than welcome to leave information in the comments.

Disclaimer #2: At a certain point I reached the limits of my ability to find answers. At that point I basically start sharing my attempt to logic out answers, or at least what the right questions might be. It may get a little muddy and I apologize. But again … this was a type of thought experiment for myself, so I figured I’d share it all the way through. I pretty much wrote this post as I researched/logiced, so it’s a pretty accurate run-through of my thought process.

Background, cont’d

In Hawking’s episode on time travel, he explains that an object with a very large mass actually slows down time around itself – and this is reflected in the GPS satellites in our orbit (they are a little bit faster, since they are a bit farther from the Earth – just a tiny bit, too little to really impact us; they gain one-third-of-a-billionth-of-a-second on us each day). It’s also been proven using aircraft flying over the Earth.

When I started doing some additional research for this post, I came to understand that no, time itself doesn’t slow down, but spacetime warps/gets longer and so it takes longer to travel across/through. This doesn’t seem to significantly impact the questions I explore below, but I don’t really want to mislead people.

To synposize while keeping this in layperson-level terms:

  • Objects produce gravity. Your fourth grade science teacher was onto something!
  • Big objects produce more gravity (big meaning “have lots of mass”; “mass” basically meaning “stuff,” as per the definition we used in live demo shows when I worked at a science museum).
  • This gravity makes time slow down a little bit (or, more accurately, it stretches spacetime so that it takes us longer to cross it – imagine if you were running on a track and someone magically expanded your 1-mile track into a 1.25-miler). To put this in literal terms, their gravity “drags on” time in much the way a toddler slows down their mom by dragging on a shirt sleeve.
  • If you could orbit the black hole at the center of our universe (I know, I had no idea, either) you’d experience time slowed to half the “speed” it moves on Earth (because the black hole is really, really, really, really big). Your body would, apparently, also age five years for our ten years on Earth. (I’m sure there will be an anti-aging intergalactic cruise program someday.)
  • The GPS satellites in orbit around Earth experience time a tiny-wee-bit faster than we do here on Earth, because they are slowed down less by the Earth’s mass (the mom is out with friends and the toddler is at home with a babysitter).
  • You wouldn’t be aware of time being slower or faster (despite the oft-cited mantra that Einstein proved that being bored makes time seem to go slower. I don’t know if that’s true, but it’s not relevant to this). Someone hanging out on those GPS satellites would feel like time was passing normally, and if they had a telescope to Earth it would look like we were moving slowly. Similarly, we feel like time is passing normally, but if we had a view up to that person in space, they would appear to us to be moving quickly.
  • Actually, though, you don’t need to go that far up in space. Just 1 km difference in height is all you need. Stick a clock 1 km higher than another, and over a million years it will emit about three more second-ticks than the lower one. So basically, you don’t need a large distance from Earth to decrease the effect of its gravity, but you would need to create a binding will that somehow requires your descendent to go check the clocks a million years later.
  • Time is, in fact, relative. Once you accept this, your head will stop hurting from trying to conceptualize all the above. I also found it helpful to imagine time as a physical object like fabric that gets pulled at by another object’s gravity (hence the toddler analogy). And imagining time as a stretchy fabric that gets pulled on is probably closer to the actual scientific explanation I found after watching Hawking’s episode.

The Question(s)
I volunteered at the DC Health Expo this weekend. I had no idea the Convention Center was so huge! I couldn’t stop wondering if you could gather enough people to produce enough mass to slow down time in a region (say, an ultra-huge Olympic-size stadium or convention center) – and how that would be reflected on all the timepieces (ie, iPhones) linked the the World Clock (or whatever that main clock is called now).

Question 1: Power to the People

So … how much mass would it take to slow down time?

And, to take a tangent – is population control at all relevant to the Earth’s impact on time around it? Would the Earth slow down time less if people and buildings weren’t on it?

For the first question: It turns out, not so much. Hawking had used the Great Pyramid of Giza as an example of an object with enough mass to slow down time – and I couldn’t find a single source that said, “That was just an analogy and not real.” So: the Great Pyramid of Giza has enough mass to slow down time for a small area around itself. The pyramid weighs an estimated 6.5 million tons. One ton equals 2,000 pounds, so – 13 billion pounds.

Okay, maybe that’s not so little.

But let’s say you brought together approximately 16 people of healthy weight – you’d already have about 2,000 pounds right there. So one ton equals approximately 16 people. And 104 million people would give you approximately 6.5 million tons.

According to Google, the US has over three times that population today. Texas alone has 26 million, one-fourth of the number we need.

Tangentially, I wondered if you need the population (the source of mass) to be dense. Texas, of course, has lots of space. So I decided to look at NYC. Population: 8.337 million, living in approximately 305 square miles (obviously, not counting vertical miles). That came out to 0.0000365839 square miles per person. Some of what I read indicated that density might be important – or shape (say …. pyramid-shaped).

Before I go any farther, I hear you asking: But does it have to be a pyramid-amount of mass?

The answer is that I don’t know. This is one of the limitations I ran into trying to do this research on my own online. Which was also part of the experiment of it: to find the limitations of a non-science/math professional doing some research mostly via Google. I found equations, but not ones that I could translate into actual math. So this is a question to throw back out there to Awesome Science People.

At the end of all this research, my conclusions are essentially that it would be far easier to give people a taste of slower time by giving them an apartment in a skyscraper; we just don’t have the structural capacity to bring enough people into a dense enough area to produce the kind of accumulated mass that would significantly slow time in any noticeable way. I do suspect, though, that human population and building structures contribute to the Earth’s mass, in an extremely limited way. I kept trying to frame this idea with word problems like the following:

Person A is on a satellite in space above the Giza Pyramid.

Person B has challenged his best friend to a virtual race using an iPhone app: they will each run 5 km. B is doing his run around the Giza Pyramid.

Person C is up in space, at the same height as Person A, above the Inner Harbor at Baltimore.

Person D, the best friend, has accepted the 5 km challenge. D is doing his run around the Inner Harbor.

So theoretically, if People A and C compare notes, they should notice that Person B (at the Pyramid) appears to be moving more slowly than Person D (at the Inner Harbor) – even though both of them appear to be moving faster than necessary, since A and C are experiencing time more slowly than both B and D.

The problem with this and any word problem I came up with is that time relativity is all about relativity. It’s all about comparing what one person is experiencing to another. You can see why my head started to hurt slightly at this point. Of course B was slower, because he’s by the Giza Pyramid. But comparing the effect of the pyramid on a person to the effect of an area without a pyramid has nothing to do with comparing the mass of the Earth with buildings to the mass of the Earth without buildings on it, because the people you need to be comparing would be – where? Up in space on a satellite, maybe?

And that’s the only way I can think of to prove whether our buildings significantly affect time around the Earth. If we had satellites with finely calibrated clocks specifically stationed over buildings of varying mass – one stationed over the Pyramid of Giza, one over the rainforest, one over the desert, one over the Empire State Building, etc, and then we compared the clocks after a year, five, ten, a thousand years.

Alternatively, if a manageable equation DOES exist for just how much the Earth should slow down time around it, we could compare the “should” answer to the “real” answer – but only if we had a comparison point (that pesky “relativity” part again), which is where I get stuck. Do we even have a concept of “normal” time? Theoretically, does “normal” time exist at all? At this point, I’m pretty sure that it doesn’t.

As for what it means if our buildings do slow time around the Earth further, I’m honestly not sure. Would asteroids slow down when they neared us, or would they just appear to move very very fast to us? Again, I defer to an Awesome Science Person.

Question 2: Technology Gone Mad

If you could theoretically slow down time, would it be reflected on people’s iPhone clocks?

This question led me through a lot of webpages trying to figure out how iPhone clocks work (or rather, how to ask the question so that I could find a relevant answer). As far as I was able to determine, it’s all GPS-based. So this means that to see a slowing in the passage of time on your iPhone, you’d need to create enough mass to impact the GPS satellites in orbit. (This science experiment may be the best reason I’ve ever heard for buying a non-digital watch – it’d be easier.) So again, this leaves us where I left off with Question 1: if we built enough Giza Pyramids, could we slow time down around the Earth?