Imperceptibly Fast

by Andy Berger

If the width of a human hair is the smallest thing visible to the naked eye, what is the shortest amount of time that we can distinguish? The phrase “in the blink of an eye” suggests an answer.  And it’s a decent suggestion.  Go ahead and blink.  Back already?  That was fast.  The average length of a blink is 0.1 seconds.  Compared to some physical processes – as shown below – that is actually a really long time.

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TOP: Time interval for some fast events.
BOTTOM: Frequency of various waves, shown directly below the amount of time for 1 period of oscillation.

I’ve always enjoyed music, as I’m sure many of you do.  In fact, one of my favorite hobbies is to play the guitar.  There is a lot of physics behind the workings of a guitar, but one of the most fascinating aspects is the speed of sound-producing processes.  Consider the simple case of playing a middle C (for those guitar players out there – this is the first fret on the B-string of the guitar, or for piano players – the key in the exact middle of a standard keyboard).  When this note is played, the string vibrates 261 times per second (or 261 Hz).

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TOP: Middle C as played on guitar.
BOTTOM: Position of the blue dot versus time.

This plot shows the position of the blue dot on the string versus time.  Note that, because it’s vibrating at 261 Hz, it takes less than .004 seconds to vibrate back and forth once.  In the time it takes you to blink, the string has gone back and forth 25 times.  While it’s vibrating, the string pushes around air molecules.  Eventually, these air molecules bump into your eardrum causing it to vibrate just like the string, and voila – you hear a middle C.

Of course, music isn’t terribly interesting if you just hear a single note at a time.  Often a guitarist might be playing a chord with six different notes, while the singer and bassist are each holding a note, all during a symbol crash and bass drum thump.  The speakers that we use to listen to recorded music have to vibrate accordingly to imitate all these different sounds (see a vibrating speaker in action).

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Signal responsible for vibrating the left and right speaker cones at 56.5 seconds into Metallica’s “No Leaf Clover.”

This is the actual signal sent to the speakers 56.5 seconds into (my favorite song) Metallica’s “No Leaf Clover.”    I chose this part of the song, because not only are there two guitars, a bassist, and a drummer playing, but they are supported by an entire orchestra.  It’s amazing to me that two tiny earbuds can accurately replicate the sound of nearly 100 instruments.  Sports fans: the amount of time depicted in this graph – .01 seconds – is the margin by which Michael Phelps won the 100m butterfly (and 7th gold) at the 2008 Olympics.

Our eardrums are not the only aspect of biology that are capable of high speed dynamics.  In my first blog post, I discussed the nanoscale machinery of DNA.  This machinery isn’t just small – it also operates very quickly.  Check out this real-time animation: DNA Transcription.  The enzyme zipping along the DNA is reading and copying the genetic code at a rate of about 30 nucleotides per second.  Try to count to 30 in one second.  In the time it takes you to blink an eye, 3 nucleotides have been transcribed simultaneously throughout the nuclei of most of the cells in your body.  I wish I had seen visualizations like this while I was studying biology, chemistry, and physics in high school.  The static illustrations in a textbook just can’t compete.

As impressive as the machinery of our cells is, they move at a snail’s pace when compared with the information processing speed of our electronic devices.  We have all come to expect a lot of our computers and cell phones.  But let’s stop and consider what has to happen to open a saved picture.  A typical image is a couple of megabytes in size.  Your computer has to individually read each of those million bytes in order to reassemble the image from the 1s and 0s that currently encode it.  If it took “the blink of an eye” (0.1s) to read each bit, it would take more than a day to load a single image!  Forget watching a video.  Luckily, a computer can shuttle information around blazingly fast.  The bits are zipping by at billions of bytes per second – and so as far as we are concerned, an image opens instantly.  To draw an analogy, when a hard drive is reading the bits that encode an image, the bit sensor is like a “jet plane flying at [18,600 miles per hour] one meter above the ground recording each blade of grass.

Technology has enabled us to do a lot in the time that passes in the blink of an eye.  It took the invention of high speed photography (1 frame every .04 seconds) to prove that all four hooves of a galloping horse are simultaneously in the air, tucked underneath its body.  Prior to these photographs, artists would incorrectly depict the position of the legs of galloping horses.  Time simply moves too fast for human perception to accurately keep up.

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TOP: Painting of galloping horses from 1821.
BOTTOM: High-speed photograph from 1878.

Today, scientists use “cameras” ten trillion times faster – taking snapshots once every femtosecond (10-15 seconds) – and can actually monitor the progress of chemical reactions.  There are 10,000 times more femtoseconds in the blink of an eye than there are years in the age of the universe.  Take a moment to pause and appreciate how quickly everything is buzzing around us, shaping our world and how we interact with and experience it.

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About Andy Berger

Picture1I grew up in Mansfield, Ohio, received my undergraduate degree from Kenyon College in Gambier, Ohio, and am now finishing my fifth year of the physics PhD program at Ohio State.  I am a condensed matter experimentalist with a focus on scanning probe microscopy, magnetism, and graphene.  I never would’ve guessed that would be my “job description” when I was in high school.  Away from the lab, I enjoy staying active – mostly through swimming, running, cycling, and soccer.

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Science: Fiction, Reality, or Both?

by Anastasia Lawson

“Oh my god, there’s robots.” This is usually my first reaction to a book or movie with robots. I love robots. I love everything about them, especially how they work and what they look like. I especially love androids, which are usually defined as robots which resemble humans. But what exactly is a robot? Today we may think of WALL-E, or Rodney Copperbottom from the movie Robots. Your parents might remember Data from Star Trek, and the Terminator movies which are full of all kinds of robots. My favorite author, Isaac Asimov, defines robots as “a computerized machine that is capable of performing tasks of a kind that are too complex for any living mind other than that of a man, and of a kind that no non-computerized machine is capable of performing.” [1]  This may sound a little confusing so let’s just say:

machine + computer = robot

But this statement was made over 30 years ago, before we had the modern computers of today, and now everything from our cell phones to toys are computerized. Today we use machines and computers and robots in a very wide range of fields and jobs. For example, welding robots are used a lot in factories which build larger machines, like cars. Robots are also being used to perform heart surgery. These robots are controlled by surgeons but use modern technology to perform the surgery faster and safer for both the patient and doctor.

You can watch this video about performing heart surgery with a catheter robot to correct irregular heartbeats.

These types of robots help to realize the past 100 years of ideas in science fiction. Isaac Asimov also wrote about characters like Andrew Martin, the Bicentennial Man, who started as a robot, but gradually built himself into a human, and R. Daneel Olivaw (where the R stands for Robot) who started as a mix of robot and human who could replace his parts and essentially live forever.

While living forever is still outside our medical technology, progress with biomedical devices and artificial limbs and organs is being made every day. For example, my dad is a walking experiment! About 15 years ago my father had a hip replacement surgery because the bone on the crown of his hip died. This is very unusual and the doctors still do not know exactly what caused it. There was no way to regrow or replace the bone with other bone so they put in an artificial metal hip. The procedure is very interesting, but also very hard on the body. They said he may have to have surgery again in 10 years, but the procedure was so new they just weren’t sure. It’s been 15 years and his hip is still fine so the doctors have told him to keep using it until there are problems.

X-rays showing the before (right) and after (left) of a total hip replacement surgery.

And this is what I love best about combining science fiction and real life. In science fiction you can make up any technology you want or use real science in a fictional way. Both of these methods can contribute to new science and technology down the road once we have a better understanding of the world around us.

So let me tell you a little about myself to explain how science fiction and science have inspired me. I am an undergraduate at OSU majoring in Engineering Physics. I’ve also studied biomedical engineering and I love anything which combines the fields of physics, biology, chemistry, and technology. I hope to graduate in a year or so and continue on to graduate school in physics or perhaps find a job in industry which focuses on a cool project. I have never built a robot, but right now I am doing undergraduate research working on a biosensor. For this project my team first makes a device which looks sort of like a computer chip but is actually a lot of tiny circuits. Then I add protein receptors to part of each circuit. These receptors then measure if a certain protein is there or not and this can be used to determine if people have a disease or not. The picture below shows the device about half way through the fabrication method, which also largely takes place in a cleanroom (for more details see What is Clean? By Megan Harberts).

device

Silicon wafer with sensors half way to completion.

This device can hopefully be used to test for a very wide range of diseases and conditions by using the protein receptor you want for whatever protein or other biological signal you are trying to measure. The device can actually work like a nerve, so someday a more advanced version could be used to repair nerve and spinal cord injuries. Imagining the science fiction applications, I hope to someday use this technology to create Asimov’s positronic brain, an artificial and programmable brain for robots.

An inside look at the circuitry of the Star Trek character Data.

So how does all of this translate to my daily life? My degree plan requires me to take a class which is actually a yearlong experiment we chose and design. My group’s project centered on creating a concussion detector we could fit into a football helmet. This project was definitely inspired by my interest in using technology to help with medical conditions. This project required me to work with physics, engineering, and programming to build a device which successfully measured how hard a player is hit while playing football. My biosensor project is also similarly inspired by once fictional, now factual uses of science. Other examples of technology created by a writer and eventually discovered by scientists include  cell phones, optical tweezers, artificial limbs, digital billboards, space travel, and tablets to name just a few.

Although it’s called “science fiction,” I think it could be renamed to “science we just don’t know yet.” For anyone interested there are robot building competitions for all ages. Science fiction has inspired me to become a scientist, and work on projects which use many areas of science to improve life for people (and robots).

[1] Gold: The Final Science Fiction Collection, Isaac Asimov, March 1995, Harper Paperbacks, New York, NY

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About Anastasia Lawson

anastasia

I am a senior in Engineering Physics. My husband Anthony and I are both in the Army. Together we like to travel around the world to see historical and cultural sites (like the Mayan ruins in Belize in the picture). I think it is very important to get young people involved in the sciences and work with several student organizations to accomplish this. My hobbies include reading science fiction, running, hiking, and snorkeling. I also love NPR, music, Great Danes, opera, and purple.

A Boy and His Atom

by Nancy Santagata

Four scientists at IBM have officially made the world’s smallest movie, “A Boy and His Atom,” in which the title characters dance and play together.  The ‘small’ comes in because the boy, appropriately named Adam, and his friend, an atom, are portrayed not by actors but by a collection of carbon monoxide (CO) molecules.  The movie frames were created with a scanning tunneling microscope, which is able to manipulate single atoms and small molecules one by one.

This is quite literally one of the coolest things that I have ever seen, and I encourage you to visit IBM’s Featured Research website to see lots of other videos related to the movie.  One thing in particular that I was super excited to learn is that two of the scientists, Susanne Baumann and Ileana Rau, are women!

A Boy and His Atom

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About Nancy Santagata

nancy_nanoLike the scientists at IBM, I use cryogenic scanning tunneling microscopy to study the properties of atoms and molecules at surfaces and interfaces. I was introduced to the technique when I was in college and have been working in the field ever since!  This is a picture of me with my instrument, which very similar to the ones used to make the movie.