Tiona (a sequel to "Vaz") (12 page)

Tiona said, “Let me make a list.” She looked up at her HUD; then started murmuring to her AI. After a minute she turned her gaze back to her father. “If it still works when they’re separated, we can try to insert probes and see if a field is being generated between the two membranes.”

“Yeah, add that to your list. We should also find out what happens to our efficiency if we make the membranes bigger or smaller.”

Tiona grinned at him, “We’ll need a set up to be able to precipitate bigger or smaller ones. Multilayer graphene is pretty hard to cut.”

“Can you precipitate some more membranes here in my lab, or will you have to go back to Chapel Hill?”

Tiona shrugged, “It depends on what kind of stuff you have in stock.”

They made a few more lists then headed downstairs to the basement to start trying to figure out what they had and what they would need to order. Once they’d placed their orders, they started trying to figure out what experiments they could do with the equipment that they already had on hand. The first and most obvious thing was for Tiona to drive to Chapel Hill and pick up all the different doped membranes she had made so far. Then they could see which of those were effective and if any particular doping scheme was much better than the others.

When Tiona returned with the folders full of membranes, her father turned to her with an excited look. “I peeled one of the membranes off of the acrylic disc and mounted it on another acrylic disc.”

Tiona laughed at herself when he said this because her initial reaction had been that he could have ripped the thin membrane trying to pull it off. But graphene was the strongest material known to man. He would have been much more likely to break the acrylic disc if the adhesive was strong enough. To her dad, she said, “What did you find with that?”

“I put the first one on top of the digital scale; then stacked paper on top of it then put the second one on. I get the most force for a given current when they’re about a centimeter apart. I’ve tried it with a centimeter thick sheet of acrylic and a centimeter thick sheet of aluminum between the membranes and I get exactly the same force so it doesn’t seem to depend on the kind of material that’s between them.”

Tiona said, “I’m going back up to my car. I brought some chemicals, copper sheeting, and other stuff to let us precipitate bigger and smaller discs. We can replace what we use that came from UNC out of the supplies we’ve ordered when they come in. I’ll just take it back when I go back to school in January.”

Vaz said, “We should try other shapes of membranes too. I can’t imagine why the effect would depend on shape, but we need to know for sure.”

Tiona frowned, “It seems to me that we should start by figuring out which dopants make the best membranes for… ‘the effect?’” She looked up at her dad, “We need a name for this effect.”

Vaz gave a sly grin and ducked his head as if a little embarrassed, “The Gettnor effect?”

Tiona snorted, “
That
would be the ultimate arrogance.
We
can’t name it Gettnor ourselves. It’d be okay if
somebody else
named it after us, but even
I’d
hate us if
we
named it after ourselves.”

“Let’s call it ‘thrust’ then. That’s what it is.”

“Thrust?” Tiona thought about it. The discs were pushing somewhere through space, so they were indeed generating thrust. She snorted, “You’re right. It’s thrust. I don’t know why I thought we had to have a fancy name for it.”

***

By the end of the afternoon, they had tested sample membranes of all of the different doping schemes that Tiona had tried so far. Though several of them produced faint thrust, only the lithium-copper membranes yielded significant force.

When Tiona got down to the lab the next morning, Vaz had set up precipitation stations on several of his benches. A very large dish was set up to precipitate lithium-copper doped graphene. He’d cut out copper templates for big discs and small discs, as well as several different shapes including squares, triangles and long slender rectangles. Two other stations were set up to precipitate doping combinations that Vaz thought might work, but that Tiona hadn’t tried since she didn’t expect they would make good superconductors. There was even one station that Vaz hadn’t planned anything for in the hopes that Tiona would have a suggestion for it.

Tiona didn’t have an idea at first, but by the time they had the other stations going Tiona suggested they try lithium-copper-titanium and they worked to set that up as well.

Once the precipitation was underway, Tiona stood up and stretched. “Well, there’s nothing to do until these new membranes are done. I’m ready for a day of vacation, how about you?”

Vaz looked at her, uneasily shifting from one foot to the other. After a moment, he hesitantly said, “I don’t have anything else to do. I’ll see if I can think of any other testing I could be doing while we’re waiting for the precipitations.”

Tiona laughed, “I’ve been having fun working with you. But, seriously,
I’m
going to go try to think of something else we could do that doesn’t involve science. How about a movie?”

“Um, on the big screen in the living room?” he asked, sounding a little apprehensive.

“No!” Tiona laughed again, “I’m trying to get you out of the house to do something different. Something social! We need to go to a theater.”

Vaz looked very uncomfortable, “Could we go to an afternoon matinee so it won’t be too crowded?”

Why do I feel like
I’m
the grownup?
Tiona wondered. Aloud, she said, “Sure. I’ll go see what’s on.”

***

The next morning, Tiona was stretching and thinking about getting out of bed when a gentle knock came on the door. “Yes?” she called.

The door creaked open and her mother stepped in. She walked over and sat down on the edge of Tiona’s bed. She said, “Feel like getting up?”

Tiona stretched again, “Thinking about it. Why? Is there a big rush?”

Lisanne grinned, “Your dad’s downstairs about to strip a gear. He won’t start on whatever big project you guys have been working on without you, but I swear he’s getting so anxious to do it that he looks like his head might explode at any moment. He’s made me coffee. He’s mixed up a batch of waffle mix, then been thinking up other little breakfast treats until we’re looking at a full size gourmet brunch down there. I don’t know
what
he’s going to make next if you don’t come down pretty soon!”

Tiona laughed, “Well, I guess I better get down there then, before we start having to invite the neighbors in to help us eat everything. Tell him to pour me a waffle. I’ll be down in five minutes.”

Lisanne stood back up, “You’re going to have to tell me how you managed to get him to go out to a movie and to dinner with us yesterday.” She winked, “You’re really improving our social life.”

Tiona got out of bed. “It takes a lot of serendipity,” she said mysteriously.

Vaz really had outdone himself with the breakfast. Tiona had a waffle with pecans and whipped cream, a couple of slices of crispy bacon, a small cup of fruit, and a large mug of hot chocolate. She reflected that it was a good thing she liked to run.

Vaz was finished eating long before she was. He sat on the edge of his seat, waiting to go downstairs. Tiona finally relented and said, “Do you want to go down and see what happened with our precipitations Dad?”

If Vaz had been a dog, his tail would have been thumping.

Tiona said, “Let’s clean up the kitchen so we can head on down.”

Lisanne laughed, “Don’t tease your father like that.
I’ll
clean up the kitchen; you guys go down and play in the basement.”

After a couple of hours of testing, Tiona and Vaz found themselves sitting and staring at their results. The lithium-copper-titanium disc had generated barely measurable thrust. The same was true for the two membranes Vaz had set up, pure copper doping and lithium-iron. On Tiona’s suggestion they had tried measuring force generation with pairs of discs that had nonmatching doping schemes, for instance, lithium-copper on top and lithium-yttrium on the bottom. The nonmatching schemes really hadn’t worked either, although a few had generated barely measurable force.

The small 2.5 centimeter discs had generated some force, though not much. Vaz had had the idea to try it with less than a one centimeter space between the membranes. The small discs generated more force with 2-3 millimeters between the membranes than they did at the one centimeter distance which had proved to be best for their standard 15 centimeter discs. Still, even with the distance between the membranes optimized, the force generated by the discs wasn’t linear to their area. The 15 centimeter discs had 36 times the area of the 2.5 centimeter discs but generated 42 times the force. Vaz’s large 30 centimeter discs had four times the area of the fifteen centimeter discs, worked best with 1.2 centimeters between them and generated 4.5 times the thrust.

Studying the numbers, Tiona said, “If we assume that the outer edge of the membrane discs don’t generate thrust, then it becomes much more linear to the area of the central portion.”

Vaz grunted. “But
how
are they generating thrust?”

Tiona shrugged.

Vaz said, “If you look at the power consumption numbers, you can see that the discs are using enough power to generate the thrust. I mean, they’re using more power than they’re turning into heat through resistance to current flow. The excess power is about the right amount to generate the thrust we’re measuring.” He turned to look at his daughter, “But,
how
is it generating thrust?!” He held up a finger, “The disc is not reacting to a magnetic field.” He held up another finger, “It isn’t reacting to an electrostatic field.” He held up a third finger, “It weighs the same before and after so it isn’t expelling matter to generate thrust according to Newton’s second and third laws. No equal and opposite reaction, eh?” He lifted one more finger, “It isn’t moving matter around itself like a propeller does or we’d feel the air blowing out the back side!”

Tiona shrugged again. She got a distant look in her eyes as she pondered the question. After a while, she lowered her head to her hands with her elbows propped on the bench top. Closing her eyes, she sat thinking.

Behind her, Vaz said, “I’m going to exercise. It clears my mind.” He stood looking at Tiona’s back as she leaned on the desk. He had hoped that she might decide to go out for a run. Vaz knew that running was the kind of exercise she preferred, and he wondered if running cleared her mind like sit-ups, push-ups, and pull-ups did for him. He didn’t really want to do his exercises in front of her, he found them embarrassing. However, she simply sat there unmoving. After a couple more moments, he turned to the pull-up bar. Instead of facing the wall like he usually did, he jumped up and grabbed the bar while facing out into the lab so that he could keep an eye on Tiona. If she started to turn around and look his way, he’d be able to drop off of the bar.

Tiona didn’t move, so Vaz started doing pull-ups. Instead of grunting a little like he normally did with each pull-up, he did them as silently as he possibly could.

Tiona still hadn’t moved when Vaz finished his forty pull-ups. He picked up the grips he used for his push-ups, eyed Tiona for a moment, then got down and started doing push-ups. Again he was careful not to make noise
although he started breathing hard by the time he’d gotten to his eightieth push-up. Tiona still hadn’t reacted, so he tucked his feet under the bench and started doing his sit-ups. He didn’t feel like he was about to get an endorphin release and started to worry. He really didn’t want to hit the heavy bag while Tiona was down there and could hear him doing it. Maybe he could just start over on the pull-ups?

At first, as Tiona sat there thinking about their experiments, she didn’t pay much attention to what her father said about exercising. However, despite her fixation on the results they’d gotten, she heard a faint repetitive squeaking as he started doing the pull-ups. She was about to sit up and turn around to see what was going on when she realized she could see him as a reflection on the flat shiny handle of the faucet on the lab sink.
He’s doing pull-ups!
When he started doing push-ups, he was down low and not visible on the faucet handle. Again Tiona started to turn but as she sat up a little straighter to do so, the angle of the reflection on the faucet let her see what he was doing. Bemusedly, she watched him do his sit-ups as well
. Holy crap! That’s a lot of pull-ups, push-ups, and sit-ups! I don’t think
I
know anybody that could do that many, even guys my age. I’m sure
some
people can, but who would have thought my dad was one of them!

Her dad stood up after he finished his sit-ups and seemed to be standing there looking at her. She could hear him breathing a little bit hard, but nothing like she would have expected. She saw him pick up something off of his bench and realized he was putting on the little lightweight boxing gloves he kept there. Then he stood and looked at Tiona again for a moment. She thought he was going to start hitting his punching bag, but instead he pulled the gloves off and jumped up onto his pull-up bar again.