Questions for James Kakalios

Can I answer your questions about superhero physics?In spring of 2006, James Kakalios, answered visitor questions about the physics of superheroes. Learn more about James Kakalios' work.

Questions and Answers

Your Comments, Thoughts, Questions, Ideas

bryan kennedy's picture

It would be cool if someone was studying how to make some of the cool inventions you read about in comic books. Are you doing any physics research into any superhero stuff? I guess I mean, as a scientist do you mostly teach or do you do research also?

posted on Tue, 12/20/2005 - 12:03pm
James Kakalios's picture

As a professor at the University of Minnesota I both teach and conduct scientific research (which I do with graduate students working on getting their Ph.D.'s, so this is also a form of teaching!). My own work involves the electronic properties of disordered semiconductors and fluctuation phenomena in neurological systems. Pretty far removed from Spider-Man or the Flash.

But while scientists don't typically look at back issues of Marvel or DC comics for research ideas, both the the best scientific study and superhero adventures, begin with the same inspiration - embodied in the question: "What if...?"

I agree that it would indeed be cool if the real world featured some of the amazing gadgets on display in comic books. The good news is that there are in fact many examples of devices first appearing in comic books that make their way into our homes!

Take Iron Man's nemesis - the Melter. He possessed a "melting ray" gun that would disolve the Golden Avenger's armor into a liquidy goo. While back in the 1960's such a device was pure fantasy - nowadays nearly everyone has such a mechanism in their kitchen, though we usually call them "microwave ovens!"

Star Trek's communicators are now called cell phones - and with web access and photo and video capabilities, are more sophisticated than what the writers of the TV series envisioned back in the 1960's.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Fri, 12/23/2005 - 2:30pm
Joe's picture
Joe says:

What is your favorite example of accurate physics in a comic book?

posted on Wed, 12/21/2005 - 11:48am
James Kakalios's picture

A classic example concerns the death of Gwen Stacy, Spider-Man's girlfriend in the immortal Amazing Spider-Man issue no. 121.

The Green Goblin had kidnapped Gwen and brought her to the top of the George Washington bridge in order to lure Spidey into battle. During their fight, she was knocked off the bridge tower. Spider-Man snagged her with his webbing at the last moment, but upon pulling her back up the top of the bridge, he discovered to his horror that Gwen had died.

A long controversy among comic book fans soon developed. Was it "the fall" that did in Gwen (as the Goblin claimed) or was it the webbing? A definitive answer is provided by physics!

Gwen sped up due to gravity, and if we ignore air resistance (which we are always doing in physics classes) then she is moving at nearly 95 miles per hour after falling 300 feet. Newton's second law of motion tells us that to go from 95 mph to 0 mph in a brief time period (let's say 1/2 of a second), that a correspondingly large force is needed. If we assume that Gwen weighs 110 pounds, then the force that the webbing must apply to halt her fall turns out to be nearly 10 G's! Thus it was indeed the webbing that broke her neck, and sadly we readers do not need to suspend our disbelief in this story - no matter how much we may want to.

The fatal aspect of this storyline is the short time the webbing has to stop Gwen. If the time to decelerate is increased, then the force needed to stop her motion is correspondingly decreased. Which is why we have air bags in our cars. Air bags do two things: (1) they spread the force needed to stop your head's forward motion in a car crash over a large area, decreasing the pressure on you (since Pressure is Force divided by Area) and (2) they deform under contact, increasing the time available to slow you down. Even a modest increase in time from 1 msec to 3 msec decreases the braking force by the same factor of three, and can turn a potentially fatal crash into a survivable one.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Fri, 12/23/2005 - 2:46pm
minda's picture
minda says:

How would a superhero fly in space when there isn't any air?

posted on Wed, 12/21/2005 - 3:50pm
James Kakalios's picture

Excellent question. Probably superheroes fly in outer space the same way they do in the Earth's atmosphere - by ignoring the laws of physics!

In the early days of Superman comics, back in the late 1930's and early 1940's, the Man of Steel could only leap great distances (such as a tall building in a single bound) but could not fly. The super-strength of his legs was ascribed to his home planet Krypton having a much larger gravity than that on Earth. Just as our muscles and skeleton structure are adpapted to Earth's gravity, so that on the moon we can easily leap over moon buildings, Superman on Earth is that much stronger since his body is adapted to the larger gravity of Krypton. But once he was able to fly, altering his speed and direction at will, then his comic book adventures became less scientific and more fantasy-based. Once you accept something as unphysical as independent flight, extending it into space isn't that big a leap (so to speak).

By the way - using Newton's laws of motion we can determine that the force your legs would have to supply in order to leap a tall building would have to be nearly 6000 pounds! Which explains why you don't see people doing this too often, and I'm lucky to leap a trash can in a single bound!

Even characters with wings would have trouble flying. Birds don't have wings growing out of their back - their arms have evolved into wings over millions of years. In order for a winged superhero's chest and back muscles to provide sufficient thrust to enable flight, their ginormous pectorals would make them muscle-bound, and consequently not too effective at fighting crime.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Tue, 01/03/2006 - 9:54pm
Anonymous's picture
Anonymous says:

Why do you think we're so fascinated by superheroes?

posted on Fri, 12/23/2005 - 12:11pm
James Kakalios's picture

Another excellent question. Back in the olden days, before computer generated special effects in movies, comic books were the main way to tell fantastic stories and incredible adventures in a graphical format. Of course, you can tell any type of story you like using words and pictures, and western and romance comic books were once quite popular, but superheroes with their incredible adventures can be best told in comic book form, and have come to dominate the marketplace.

As to why we remain so fascinated by these tight-wearing heroes, I personally like an idea proposed by Jim Henley. He suggested that superhero tales served as a Literature of Ethics, that explored issues of Good and Evil, and what our obligations are to others, friends and strangers, in an entertaining manner. If you had a superpower or special ability, would you spend your free time risking your life to help complete strangers, for no pay? And when would you ever be "off duty?" After all, this is what volunteer firemen routinely do. Superheroes offer the creative freedom of looking at the world in an original way (say at super-speed or the size of an ant) while providing a platform to examine ethical issues within an exciting story.

And they're really cool!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Tue, 01/03/2006 - 10:07pm
Anonymous's picture
Anonymous says:

Could Batman's tools really let him do all the things he does, or would his arms just get ripped out of their sockets?

posted on Fri, 12/23/2005 - 12:12pm
James Kakalios's picture

You're right to be suspicous. The accelerations that Batman's grappling gun would produce should lead to large strains on the Caped Crusader's arms and joints. As he swings among the rooftops of Gotham, the tension in his Bat-line could easily exceed 300 pounds, which would be transmitted to his arms and shoulders. However, years of training and conditioning have brought Bruce Wayne to the peak of physical perfection. In addition, his uniform would be reinforced to provide support at crucial points. So, while this mild-mannered physics professor would not be able to carry out such exertions, it is borderline plausible that the Darknight Detective would be able to perform such feats.

Now, if you want unrealistic - consider the number of times that Batman has been knocked unconscious in his over 60 years of fighting crime, and it is clear that he should be severly brain damaged by now!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Tue, 01/03/2006 - 11:28pm
Anonymous's picture
Anonymous says:

Hey, how much food would the Flash have to eat to be able to run as fast as he can? And how much oxygen would he breathe?

posted on Wed, 12/28/2005 - 5:56pm
James Kakalios's picture

Short answer: A lot!

As the Flash runs, he converts the stored potential energy derived from the food he ate into the kinetic energy of motion. Assuming that the Flash has a mass of 70 kilograms, if he were to run at 1% of the speed of light, his kinetic energy would be over 300 trillion Joules. Assuming that he is able to convert 100% of the food energy into kinetic energy (and for us non-super-powered mortals, half of the calories in the food we eat goes toward metabolic functions such as maintaining body temperature), then the Scarlet Speedster would need to eat over 150 million cheeseburgers, just to run this fast! Once! Even chewing at super-speed, he would seem to have little time left for stopping Captain Cold and the Trickster.

Breathing is actually more plausible, simply because of the magnitude of the Earth's atmosphere. If his oxygen intake is comparable to that of an elite runner, per kilogram of body mass per mile ran, then he would have to run at the speed of light for over 27 million years before he used up all of the Earth's oxygen. So, we can all breathe easier!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Tue, 01/03/2006 - 11:41pm
From the Museum Floor's picture

If you could pick only one superhero to learn about which one would you pick and why?

posted on Mon, 01/02/2006 - 11:27am
James Kakalios's picture

Let me pull a Jim Kirk on the Kobiyashi Maru simulation and change the terms of the question.

If I had to limit myself to three superheroes, I would choose the Flash, the Atom, and Iron Man. The Viceroy of Velocity would enable me to discuss a wide range of physics phenomena connected with speed, ranging from conservation of energy, to the Doppler effect, to shock fronts in the atmosphere, to Special Relativity. A consideration of the Tiny Titan would bring in all physics that is sensitive to length scales, and even lead to Quantum Physics as the Atom became as small as, well, an atom. And Iron Man's armor, containing a host of transistorized technology, would bring in many practical applications of the basic physics principles discussed earlier.

So, that would be the only one superhero I would use, if I had to choose only one!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Tue, 01/03/2006 - 11:47pm
Anonymous's picture
Anonymous says:

What is the most interesting super hero concept that has become, or is becoming reality?

posted on Thu, 01/05/2006 - 1:47pm
James Kakalios's picture

While it has not yet been confirmed as a reality, the fact that some theoretical physicists are seriously discussing "parallel universes"and "alternate Earths", concepts first introduced into comic books in the early 1960's, would certainly qualify, in my opinion.

Back in 1957, Hugh Everitt III proposed in his Ph.D. disseration in physics an alternative interpretation of quantum mechanics, that has become known as the Many Worlds Model. Here the probabilistic interpretation of conventional quantum theory, whereby the Schroedinger equation enables us to predict not the location of an electron in an atom, for example, but only the likelihood that it will be at a given spot at some point in time, is replaced with something even harder to accept. Namely, Everitt argued that for every quantum process that has at least two possible outcomes, an equivalent number of universes, parallel to but not interacting with each other, are created. This idea has not been taken seriously until fairly recently, when some theroetical physicists, trying to develop a theory of Quantum Gravity, have found it a necessary concept that avoids other problems with their model.

If experimental proof of this concept is ever provided, then we physicists may one day face our very own Crisis on Infinite Earths!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sat, 01/07/2006 - 9:13pm
Anonymous's picture
Anonymous says:

Who is your favorite super hero?

posted on Fri, 01/06/2006 - 2:03pm
James Kakalios's picture

I've always like the Flash - and nowadays with all that I have to do in a day, I must say that I'd love to possess "super-speed." Another favorite of mine is the Fantastic Four, and in particular, their leader, Reed Richards, aka Mr. Fantastic. In addition to having cool elastic powers, he was a super-genius, and frequently would out-think his adversaries.

And of course, I'm partial to the Atom, for in his secret identity he is Ray Palmer, Physics Professor! Not often do comics tell the truth about the lives of excitement and adventure that we physics profs lead!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sat, 01/07/2006 - 9:19pm
Josh D.'s picture
Josh D. says:

Is it plausible that the Flash could vibrate to fast as to pass through a solid object without destroying said object?

posted on Fri, 01/06/2006 - 5:14pm
James Kakalios's picture

No, not really.

The Flash's ability to pass through solid matter was attributed to his being able to match his body's vibrations to the natural vibrations of the atoms in a wall or other barrier. Now, the atoms in a wall (or anything else for that matter) do indeed vibrate, owing to the fact that they have thermal energy, as reflected in their being at room temperature. But two objects, both at the same temperature, can not pass through each other.

There is a quantum mechanical phenomenon termed "tunnelling" whereby any object has a very small but non-zero probability of passing through a barrier, without harming it or itself. The faster the object is moving, that is, the larger its kinetic energy, the greater this probability, and by vibrating back and forth one has many opportunities for this small probbaility to enable a tunnelling transition. But even so, when you plug in the numbers, the likelihood of the Flash being able to "vibrate" through a wall is exceedingly small. So, I would tend to lump this ability of the Flash's with his "miracle exception" from the laws of nature, that account for his super-speed and ability to withstand air resistance and enormous accelerations. It makes for better stories when you cut them a break from time to time.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sat, 01/07/2006 - 9:32pm
Adam wentz's picture
Adam wentz says:

What kind of things are you working on in your scientific studies?

posted on Sat, 01/07/2006 - 3:36pm
James Kakalios's picture

Thanks for asking! The body of knowledge in physics has become so extensive that continued progress comes from physicists who choose to specialize in either experimental or theoretical investigations. I am an experimentalist, that is, I work in a laboratory, and my particular sub-field is solid state (sometimes also known as "condensed matter") physics.

In particular, the two main research projects I have underway at the present range from the "nano" to the "neuro." Along with colleagues in the University of Minnesota's Departments of Mechcanical Engineering (Prof. Kortshagen) and Chemical Engineering and Materials Science (Prof. Carter), we are developing thin film amorphous silicon semiconductors containing nanocrystalline silicon inclusions for solar cell applications. Other labs have reported that including the nanocrystals may lead to materials with superior properties for solar cells - we are investigating these claims.

My other research thrust involves a collaboration with a professor in the Neuroscience Department at Minesota (Prof. Redish). For years at Minnesota I have studied the properties of electronic noise in amorphous silicon, using the fluctuation phenomena as a probe of the interactions between the current pathways in this highly disordered material. For the past few years we have the applied statistical techniques developed in solid state physics to voltage traces recorded from electrodes surgically implanted in rats as they perform a variety of tasks. This approach has yielded interesting results, and we have identified a coherent oscillation signal that is correlated with the animal initiating a particular task. Figuring out what it all means, as well as pushing forward on the semiconductor studies, will be alot of fun and keep us busy for a while!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sun, 01/08/2006 - 1:46pm
Anonymous's picture
Anonymous says:

If a person were strong enough to lift something massive (like Colussus lifting a truck) would our bones be strong enough to do it?

posted on Mon, 01/09/2006 - 2:16pm
James Kakalios's picture

The strength of our muscles and bones depends on their cross-sectional area. Think about fishing line - the size of the fish that the line can support depends on its diameter and not its length. If a line is too thin to hold up a large fish, making the line longer won't help. Similarly, the strength of our bones and muscles depends on their cross-sectional area. So, if the muscles became larger, and the bones grew in the same proportion, then
in principle the bones could indeed be strong enough.

However, there are at least two caveats. One - if you became stronger by becoming large - such as Giant-Man, then your mass increases as the cube of your height (assuming expansion at constant density), while your bones become stronger but only as the square of your growth. So, at too large a height (say 60 feet) you risk breaking your back just by standing up, as your weight increases faster than your skeleton's ability to support you. Since Colossus becomes stronger by converting his body to "organic steel" (and no, I have no idea what this is) he presumably becomes stronger by making both his muscles and bones denser, so he should be ok here. The second warning involves ligaments and the connections of the muscles to the bones. these occur at essentially isolated points, and it is here that the stress involved in lifting a truck would be focussed. It is more likely that Peter Rasputin's muscles and bones could stand the strain, but his tendons wouldn't.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Wed, 01/11/2006 - 10:18pm
From the Museum Floor's picture

Is it possible to travel at the speed of light and to go back in time?

posted on Mon, 01/09/2006 - 2:33pm
James Kakalios's picture

No.

If you were to travel at the speed of light, time would seem to pass at the same rate for you, but everyone else would appear (to your point of view) to be frozen, due to a consequence of Einstein's Special Theory of Relativity termed "time dilation." This leads to all sorts of interesting thought experiments, such as the "twin paradox" which I don't have the space here to go into.

So, I'll stick with my first answer. No.

[An excellent brief (at only 65 pages with figures!) and highly readable reference is L. D. Landau's and E. B. Romer's "What is Relativity" (Dover Press, 2003).]

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Wed, 01/11/2006 - 10:30pm
Anonymous's picture
Anonymous says:

How does the spider's bite affecct Peter Parker's DNA?

posted on Mon, 01/09/2006 - 3:19pm
James Kakalios's picture

I have no idea. Changing Peter Parker's DNA would determine whether his children gained spider-powers, but as I understand biology (and here I must stress that I am not a biologist), it should not bestow wall crawling abilities to puny Parker. The acquisition of super-powers here would fall under the "one-time miracle exception" (from the laws of nature, that is) that must be granted to any superhero in order to get the story going.

I for one am willing to suspend disbelief long enough to enjoy the latest adventure of the amazing Spider-Man.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Wed, 01/11/2006 - 10:37pm
Anonymous's picture
Anonymous says:

How can spider-man stick to walls while wearing gloves?

posted on Mon, 01/09/2006 - 3:20pm
James Kakalios's picture

Presumably his gloves are thin enough to allow his setae to extend from his fingertips to the wall.

Gecko lizards have millions of little filaments called setae growing from the pads of their feet. Fluctuations in the electrical charge distribution in these filaments induce an electrostatic attraction in the nearby wall. This effect, termed the van der Waals attraction, is extremely weak, which is why the gecko needs millions of these fibers to hold him to the wall or ceiling.

In the 2002 film Spider-Man, we saw a close-up view of Peter's fingertips which sprouted thousands of barbed fibers. These must function as the setae of a gecko, and as long as they can poke even slightly through the cloth of his gloves and boots, he would be able to adhere to any surface.

Materials scientists and engineers are trying to develop "gecko-tape" that would function in a similar manner. If this ever becomes as common as velcro, I for one will never wait for the elevator again!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Wed, 01/11/2006 - 10:44pm
Anonymous's picture
Anonymous says:

Are genetic mutations going to be a problem in the furture, with all of the unatural chemicals that people are exposed to daily? I don't think we could walk through walls, but is advanced hearing or eyesight through genetic mutation possible?

posted on Wed, 01/11/2006 - 1:00pm
James Kakalios's picture

Well, as I said before replying to an earlier question - I'm no biologist, nor do I even play one on TV! I tend to doubt it, as I understand how mutations work.

Now, if you are interested in technological fixes, as opposed to biological, to hearing and eyesight, then there is indeed good news. Our bodies take in sensory inputs through a variety of channels, and transform this information into voltages that are then processed by our nerve cells. Recognizing this, and with the development of advanced lightweight materials and semiconductors, scientists have developed artificial choclea that have proven very successful in helping the hearing impaired. Whether the gain and/or frequency range could be adjusted to allow the detection of sounds not ordinarily within our range of hearing (super-hearing?), I do not know.

Similarly, biophysicists and other scientists are working on developing artificial retina, for treatment of certain types of blindness. The rods and cones in the eye absorb photons of visible light, and output a voltage that is detected and processed by the optic nerve. This basic photon absorption process is analogous to what occurs in a solar cell, that transforms sunlight into an electrical current. The artificial retina is still in the developmental stage, and whether the range of light recorded could be broadened into the infra-red and ultra-violet (super-vision?) is doubtful. For one thing, as with the artificial cochlea, it is not clear that our nerve cells and brains can process information that originates from outside the normal range of inputs. Such frivilous speculations aside, just being able to treat hearing and vision impairments in this way is a serious and noble benefit of the scientific endeavor.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Thu, 01/19/2006 - 11:16am
Anonymous's picture
Anonymous says:

How is that the FFs' uniforms can accomodate their super powers? Stretching, not burning, and my favorite turning invisible for instance.

posted on Wed, 01/11/2006 - 5:10pm
James Kakalios's picture

The Fanstastic Four's costumes are able to stretch, burn or turn invisible because they are composed of one of Reed Richard's miraculous inventions: Unstable Molecules. Now, any high school chemistry student can tell you that unstable molecules really do exist - they are the ones that explode or fall apart because they are unstable!

However, closer to home are "smart fabrics" that can change their thermal insulation properties or elasticity depending on the wearer's needs, and that are already available in high-end athletic wear. These are modern versions of "shape memory materials" that can "recall" their prior configuration after being twisted or deformed. Not quite as impressive as the FF's uniforms, but more reasonably priced, and they come in other colors than just blue.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Wed, 01/11/2006 - 10:51pm
Anonymous's picture
Anonymous says:

batman is my favorvite superhero -how does his batterang work?

posted on Sat, 01/14/2006 - 6:15pm
James Kakalios's picture

The original bat-arang was a fancy boom-arang. As anyone who has thrown a real boom-arang can attest, getting them to return to the general vicinity of the thrower is highly non-trivial, and relies on some quite complicated aerodynamics. That the Dark Knight Detective's bat-arangs always would strike their target - and then return to the Caped Crusader! - shows the benefit of throwing such an object in a comic book as opposed to real life!

Years later, Batman would employ a "grappling gun", as shown in the film "Batman Begins" and the Animated Batman show, that used explosive propulsion to shoot a grappling hook to an upper story, and then a motor would reel in the line attached to the hook, enabling Batman to rapidly ascend the side of a building. Questions as to the nature of the power supply in the handheld gun that provides sufficient force to lift Batman as well as a thug or innocent bystander he is holding, will be left to another time.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Fri, 01/20/2006 - 9:32pm
Anonymous's picture
Anonymous says:

Would it be possible to create a web shooter?\r\n\r\n\r\n

posted on Sun, 01/15/2006 - 3:41pm
James Kakalios's picture

Sure - in fact, they are available at most toy stores, shooting "silly string" with the press of a palm-located button.

Now if you want something with more adhesive properties than silly string, this is in the works. Materials scientists are working to duplicate the structural properties of real spider's dragline silk. A spider's web can have a tensile strength, pound per pound, five times greater than steel cable, and is stretchier than nylon. This is because the webbing contains thousands of nanometer length filaments along its length, providing a great deal of redundancy. The webbing is filled with fluid, so that the force is uniformly distributed along its length. If we are ever able to artificially mass-produce fibers with the material properties of dragline silk, the fabrication of lightweight clothing tougher than Kelvar could become commonplace.

And within minutes, someone will think to use this man-made webbing in a silly string shooter!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Thu, 01/19/2006 - 11:28am
Anonymous's picture
Anonymous says:

how does radiation effect people?

posted on Mon, 01/16/2006 - 1:42pm
James Kakalios's picture

It depends on what kind of radiation.

The term "radiation"covers a broad range of natural phenomena. Light is more properly termed "electromagnetic radiation" and can be quite benign - think of the radio waves you are constantly bathing in right now - or very hazardous - too much exposure to X-Rays or Gamma-rays (or even ultraviolet light) can be very bad.

The key issue is the wavelength and corresponding energy of the light. The shorter the wavelength, the higher the energy of the electromagnetic radiation. Radio waves have wavelengths of several feet or so, and thus do not interect with us at the cellular level. Ultraviolet light, on the other hand, has a wavelength that fits inside a skin cell, and its penetrating energy can cause significant damage at the cellular level. The wavelength of X-rays is on the order of the size of atoms, while that of gamma rays is as big as an atomic nucleus, and their energies are correspondingly much larger. They can therefore damage many cells with a single photon, and if the damage is to a sensitive part of your DNA, the results are very serious. Of course, if the dose is kept carefully low enough, brief exposures can be tolerated by your body, as in a visit to the dentist's office.

The term "radiation" is also employed to describe the by-products of the decay of certain atomic nuclei. They ejected matter can be as small as an electron (originally termed "beta rays" before the electron had been discovered) to a helium nucleus of two protons and two neutrons (also known as an "alpha particle"). Alpha particles tend to be emitted with much higher energies than beta rays, and tend to do more damage at the cellular level. Again, the key question is the intensity of radiation that you are exposed to.

We evolved in a background of a certain level of radiation, and as long as your exposure does not exceed that occuring naturally, you should be fine. And sad to say, radiation either is ignored (as in radio waves) or harmful (as in too great an exposure to alpha particles or gamma rays) but has never been known to bestow super-powers or strange abilities far beyond that of mortal man.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Fri, 01/20/2006 - 9:21pm
Anonymous's picture
Anonymous says:

Could spiderman's webbing really hold a truck?\r\n

posted on Mon, 01/16/2006 - 3:00pm
James Kakalios's picture

Most definitely! As I indicated in the reply to the question about web-shooters above, if Spidey's webbing is anything like a real spider's dragline silk, then it would be more than tough enough to hold back a truck or even a runaway train (as in the film Spider-Man 2), provided its diameter were thick enough. A webbing with a diameter of only one quarter of an inch could easily support 6000 pounds before snapping. Which is why materials scientists are hard at work trying to develop comparable webbing in the laboratory (it being somewhat difficult to milk the spiders directly).

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Thu, 01/19/2006 - 12:07pm
Anonymous's picture
Anonymous says:

why are apes, which are similar in size to humans, so much stronger? they seem to have "superhuman" strength

posted on Sat, 01/21/2006 - 5:47pm
James Kakalios's picture

They don't really - they actually have "ape strength." Ape's skeletal and muscular structure are optimized for the tasks they need to perform - by hand. Our evolutionary advantage - our large brain - has led to us not needing to do these same tasks by hand, as we have figured out how to employ tools to carry out feats of strength that apes can only dream about.

Similarly, I can out pace the fastest cheetah - once I start the car, that is. Actually, on a serious note, what we humans lack in bursts of speed we make up in endurance. Richard Leakey once ran down an antelope (in order to show that our ancestors could do it). He just kept running at a slower but steady pace. The antelope initially eluded him easily. But by not giving the antelope much time to rest and recover, he eventually wore it down so that he could get close enough to capture it. The race is not always to the swiftest, after all.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Thu, 01/26/2006 - 9:33pm
From the Museum Floor's picture

How can Dash (from the Incredibles) run on water?

posted on Mon, 01/23/2006 - 11:16am
James Kakalios's picture

This is not such a far-fetched example superpowers - once you grant the "miracle exception"from the laws of nature of super-speed, that is.

Water is a fluid, similar to air - though obviously denser. When you try to move faster than the speed of sound in air, you build up a shock front of air in front of you, as you try to push the air molecules out of your way faster than they are moving, just zipping about. Similarly, if you strike the surface of water with your foot faster than the water molecules can respond, the region underneath your foot will behave in a "solid-like"manner. Try slapping very hard and fast the surface of ater in a swimming pool and you'll feel the water resisting your attempt to displace.

What Dash and the Flash are doing when they run across the surface of a body of water is essentially bare-foot waterski-ing, but without needing a fast motor boot to pull them.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Thu, 01/26/2006 - 9:41pm
Carmen_Freak_Chicken's picture
Carmen_Freak_Chicken says:

When Colossus transforms into his organic steel form, he increases both in volume and in mass. How can this be if mass cannot be created?

posted on Tue, 01/24/2006 - 7:55am
James Kakalios's picture

Well technically mass can be created, through Einstein's equation E = mass multiplied by the speed of light squared. Scientists in the mid-1990's confrimed that matter can be formed from energy when they were able create electron-antimatter electron pairs through the collision of high energy gamma ray photons. The gamma ray experiment was extremely difficult, produced only a small amount of matter, and always an equal amount of antimatter for every particle of matter generated. Nevertheless, it can be done, which has inspired comic book writers to argue that when Colossus, Giant-Man, the Hulk and other transforming heroes grow, they do so through a mechanism that involves the conversion of energy into matter.

As to where this excess energy comes from, or where it goes when these heroes revert to the original smaller size - well, that's a separate question. It's been suggested that the excess energy is shunted back and forth through another dimension. which is just a fancy, technical sounding way of saying: "relax! it's just a comic book!"

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Thu, 01/26/2006 - 9:54pm
Masoud's picture
Masoud says:

In comics there have been quatum based powers, the best I can think of right now being Quantum Kid of the Legion of Super Heroes. But I still have no idea what having quantum powers would mean.

If I had quantum based powers, what would I be able to do?

posted on Thu, 01/26/2006 - 8:32pm
James Kakalios's picture

An excellent question. "Quantum" refers to Quantum Mechanics, the branch of physics that describes the behavior of electrons and atoms, and their interaction with light and other forms of energy. The amazing discovery at the turn of the last century (that is, back in the 1900's) that atoms could only change their energy in discrete intervals, termed quanta (for the Latin "how much") led to a theory of atomic behavior that would in turn eventually lead to the development of the transistor and laser. Since these inventions underlie CD players, cell phones, DVD players, personal computers, iPods, and so on, the modern technological lifestyle that we enjoy would not be possible without the efforts of a few pioneering physicists.

It would take too long to describe the basis of quantum mechanics here. A brief overview of the key concepts underlying quantum theory can be found in my book THE PHYSICS OF SUPERHEROES, available at the Museum gift shop and all major bookstores (who says this isn't the Marvel Age of shameless plugs?).

Regarding superheroes and their "quantum" powers, since quantum mechanics describes how atoms interact with energy, what holds them together, when they may fall apart, and under what conditions they can bind together to form molecules, then any hero that has "elemental powers" would qualify as a quantum mechanic (sorry about that!). So, Element Lad of the Legion of Super Heroes, the Fantastic Four foe Molecule Man, and Thor's nemesis The Radioactive Man could all be said to posses "quantum" abilities.

Oh, and quantum theory also predicts that under certain conditions, electrons can pass through an ordinarily impenetrable barrier, without harming itself or the barrier. This phenomenon is called "tunneling" and is no less mysterious for being true. Certain transistors in your cell phone would not function if tunneling were not a routine and dependable process. Evidently Kitty Pryde of the X-Men is able to adjust her quantum mechanical tunneling probability at will, which is how she can walk through walls. Pretty handy when you've locked your keys in the car, I must say.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Wed, 02/01/2006 - 10:31pm
fairytoes12's picture
fairytoes12 says:

in the fantasic four johnny storm's dna was changed by costmic rays what were those rays made of and how did they change his dna without harming his body

posted on Fri, 01/27/2006 - 2:28pm
James Kakalios's picture

Cosmic rays are essentially very fast moving protons that originate from sources as close as our sun and as far away as other galaxies. When these protons strike atoms in our atmosphere, they, through the Einstein relationship E = mc-squared, create showers of other high energy particles, from electrons, muons, X-rays, pions and other elementary particles. Most of these particles are unstable - muons, for example, close cousins of electrons, decay away in 2.2 millionths of a second.

But in outer space, where Johnny Storm, his sister Sue, Reed Richards and pilot Ben Grimm encountered the mysterious storm, cosmic rays are basically protons. Since they are moving very close to the speed of light, they will cause extensive damage at the cellular level when they strike your body. This damage will extend to the DNA, and will be for the most part indiscriminate. Such wholesale destruction leads invariably to cancer, and not superpowers, unfortunately.

Which is why I am always willing to grant a "miracle exception" from the laws of nature when reading a comic book story. The Fanstastic Four, in particular, are some of my favorite characters, and I much prefer to believe that they gained amazing abilities from their historic cosmic ray shower, and not anything remotely physically realistic.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Mon, 01/30/2006 - 10:56pm
Anonymous's picture
Anonymous says:

How could I build a real light sabre?

posted on Sun, 01/29/2006 - 4:59pm
James Kakalios's picture

I wish that I knew. But this elegant weapon from a more civilized time is sadly pure fantasy. There is no way that light, which travels 186,000 miles in one second, could be formed into a solid, three foot long shaft. Of course, wave packets of light that are finite in extent can be constructed, but they would travel at the speed of light as well. There would have to be a mirror or some other reflecting surface that the end of the light saber to constrain the light beam, and then it would be as insubstantial as, well, light.

Besides, as a wise man once said, ancient weapons and hokey religions are no substitute for a blaster at your side!

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sat, 02/04/2006 - 6:17pm
samantha Schmidt's picture
samantha Schmidt says:

What exactly is an atom?

posted on Fri, 02/03/2006 - 12:01pm
James Kakalios's picture

Take a small cube of copper, about the size of a sugar cube. Cut it in half, and then cut one of the halves in half again. Continue this process for roughly another 74 bisections. You will ultimately be left with the smallest element of the copper cube that still retains the essential "copper-ness" of the material. This will be a copper atom. It will have a small positively charged nucleus of 29 protons and typically 35 neutrons, around which buzz negatively charged electrons. The electrons are quite far away on average - if the nucleus was the size of a child's marble, and placed in the end zone of a football field, then the nearest electrons would be in the opposite end zone, 100 yards away. The number of protons in the nucleus, and an equal number of oppositely charged electrons swarming around it, determine the chemical and optical properties of the atom, and in turn will govern the properties of a large macroscopic hunk of matter comprised on these atoms.

By the way - you didn't ask, but I'll toss it in for free (who says this isn't the Marvel Age of "Service with a Smile"? )- molecules consist of at least two atoms (though they can consist of over a thousand atoms) chemically bound together. Two hydrogen atoms combine to form the molecule H2, and with the additon of an oxygen atom, we have the familiar water molecule H2O.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sun, 02/05/2006 - 12:36pm
Anonymous's picture
Anonymous says:

what causes elcetronegativity in atoms?\r\n

posted on Fri, 02/03/2006 - 6:13pm
James Kakalios's picture

The electronegativity of an atom is a measure of how strongly it attracts an additional electron as it forms a chemcial bond with other atoms. As electrons are negatively charged, they repel each other when brought into close proximity. Any given atom has a certain number of negatively charged electrons, that are attracted to the nucleus by an equal number of positively charged protons. (The protons are kept together in even closer proximity in the nucleus by a separate nuclear force that is so strong, it is called the Strong Force).

However, quantum mechanics posits a "wave-like" property for the electrons in atoms. Consequently, when an electron in one atom is brought near another atom, the "matter-waves" can, under the right circumstances, set up an interference pattern that lowers the total energy of both atoms, and they then form a chemical bond as a molecule. The details of what determines the magnitude of this lowering of energy, related to the atom's electronegativity, is quite complex. Generally, the larger the atom, the more electrons it has, which screen out the positively charged nucleus, and the lowers the electronegativity.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sat, 02/11/2006 - 1:30pm
Taylor's picture
Taylor says:

ONE more thing, mabey 10 years from now do you think we could teleport?

posted on Mon, 02/06/2006 - 8:50pm
James Kakalios's picture

I'm afraid not. Not in ten years - nor ten thousand, unless there's a radical restructuring of physics in the intervening time. To disappear in one location and reappear at another would involve destroying all of the atoms in your body and then recreating them in a different location. Assuming you had the energy available to perform this little trick, you would have to be able to reproduce the location and velocity of every proton and electron with a finer resolution than allowed by the Heisenberg Uncertainty Principle - if you wanted to be identical following the teleportation. (Change the location of a few neurons, and you wind up writing the wrong check, and it costs you some real money!).

This is all spelled out clearly in Lawrence Krauss' excellent book "The Physics of Star Trek."

Perhaps if we can develop portable wormholes, such feats may be possible, but for the next ten years - you should just resign yourself to getting stuck in traffic.

Your Friendly Neighborhood Physics Professor,

Jim Kakalios

posted on Sat, 02/11/2006 - 1:12pm