Enlarge / ] Scott Lang, aka Ant-Man (Paul Rudd) and Hope van Dyne, aka Wasp (Evangeline Lilly), would need 100…
The ability to quickly shrink to bug size (and beyond) gives Ant-Man and Wasp huge benefits. But it also comes with some scalar-related disadvantages, especially more difficult breathing. Trick out their costumes with insect-inspired microscale air pumps, compressors and molecular filters, combined with the fictional “Pym particle” technique, a voila ! Problem solved.
Anne Staples, bio engineer at Virginia Tech and her doctoral student Max Mikel-Stites first outlined breathing difficulties. Ant-Man and Wasp were likely to meet the insect size in a paper published this summer in the Fling Journal Superhero Science and Technology. (Can I just say, how happy I am, that this journal exists?) The group investigates respiration by microscope, using insects as models. They described their work at a meeting in the American Physical Society’s Division of Fluid Dynamics in Atlanta, Georgia.
Mikel-Stites, a fan of the Marvel Film Universe, stoke for Ant-Man and Wasp ] release. So one day in the last spring lab, the conversation of course turned out how difficult it would be for the superheroes to breathe when the insect size. Applying this perspective to Ant-Man and Wasp seemed like an easy thing to do, says Mikel-Stites, who admits that she is a bit nitpicky in terms of science in the movies. And he could not stop thinking about the breathing problems that our superheroes would inevitably encounter.
A. Klammer / M. Mikel-Stites
The smaller the animal, the less metabolically effective it is according to Kleiber’s law (named after biologist Max Kleiber). It is probably due to the fact that the ratio between surface and volume increases as objects become smaller. “Animals create heat in amounts that are proportional to the body’s volume, but release the heat in amounts proportional to the body’s surface,” says Staples. “So small animals that have large surface area to volume ratios, release the heat with high levels and can not stay warm.” To compensate for heat loss, they need higher metabolic rates. Small animals therefore give more heat and require more oxygen than larger.
Granted, it is not clear from the Marvel films if Antemans mass also scales down as he shrinks. “Sometimes it seems that he has a human mass – he falls and bursts a tile floor – and sometimes he seems to have the mass of an ant [when] as he drives a gunpipe and rides on Ant-Thony, his antagonist, says Staples.
“The subjective atmospheric density is experienced by a human who shrinks down to changes in insect size. “
They decided to assume that the masses of Ant-Man and Wasp were peeled off with eight magnitudes as they shrank down to insect size, meaning that their total metabolic rates would only decrease by six orders. This is converted into a per unit mas s 100 times greater than the super hero would have when they are human medium so they would need 100 times more oxygen to function.
“While the actual atmospheric density is the same for an insect and a human being, the subjective atmospheric density experienced by a person who shrinks down to changes in insect size, says Mikel-Stites. When Scott Lang inhale in his normal size, he breathes in a certain number of oxygen molecules. Shrink to ant size, but he still needs the same number of oxygen molecules, but accumulates much less with each breath.
It corresponds to the mountaineers on Mt. Everest’s experience at the summit is the infamous “death zone” of 7,998 meters above sea level. Most people respond to these conditions by breathing faster to get more oxygen, if only to avoid headache and dizziness that is common for altitude sickness.
A. Klammer / M. Mikel-Stites
Fortunately, microfluidic devices – the typical staples and her group develop – can help. Insects and humans developed very different breathing strategies because of the very different scales they live on. According to the staples, many insects collapse their tracheal pathways when they breathe. No two insects do it in exactly the same way, but it usually means abdominal contractions to trigger the collapse. “Sometimes the collapse spreads along the tracheal pathways in a constriction wave, and sometimes the collapses fall into separate places along the same tracheal pathway,” she says.
The Virginia Tech team units mimic different combinations of these three main features of insects breathe. By utilizing these strategies, the group has managed to build four (so far) insect-inspired small lab-on-chip machines that allow them to control fluids in small weights with great precision without having to choke valves. An essay on this work awaits publication, and Staple’s colleague Krishnashis Chatterjee describes some preliminary results at the conference.
So how can microfluidics help our superhero lovers to breathe in smaller sizes? To compensate for insufficient suction power to pull air into the helmet’s mask, it would be possible to pump the air with something called a “Knudsen pump”. This is due to differences in temperature to pump gases (like air) through nanoscale pores in many minerals. There would definitely be a temperature difference inside and outside Ant-Man and Wasp costumes.
A. Klammer / M. Mikel-Stites
Further, there would be some ways to compress air supply to achieve acid molecule densities at sea level level (as opposed to Everest’s high altitude death zone). This assumes Ant-Man and Wasp retain their human masses. “Compressing the air would allow them to get the same number of oxygen molecules in a lung-like air,” says Staples. “There are a number of microcalk compressor technologies available, such as microscale membrane compressors, which can be operated mechanically or electrostatically.”
Finally, addition of a molecular filter (as an H filter) can also help superheroes to cope with increased oxygen demand. Such a filter would remove smaller non-oxygen molecules from the air, which increases the relative oxygen content, utilizing the different diffusion timescales for molecules of different sizes. Combine these three with Pym particles, which are said to allow reduction or expansion in the distance between atoms and matter, as well as manipulate pulp – and you have a viable solution to breathing.
The staple group debated which superhero they should choose for their next depression in the comic book’s physics. Ever the Marvel fan, Mikel-Stites pushed to Dazzler, who has sonoluminescent powers (think the sonic shockwave produced by the powerful snap of a cloak of a mantis claw written great). But the student Student Afreen Khoja (and DC Comics) won: they will investigate Meras hydrokinetic powers Aquaman ‘s Princess of Atlantis.
DOI: Superhero Science and Technology 2018. 10.24413 / sst.2018.1.2474 (About DOIs).