noise in here, and among the noisiest were Joe Antoniadi and Mike Wetherbee. Joe, an Italian-American whose family had fled New York, was likable, friendly, easy to impress. Even as Zheng talked, Mike was cracking jokes in his broad Australian accent and making Joe laugh. Mike’s family were refugees from an almost entirely abandoned continent.
They reached their table. Zane had a laptop, and Holle dug her handheld out of her bag.
If the students had been indifferent to Holle, Liu Zheng didn’t so much as register her presence. He just carried on with what he was saying. “So how do you fly to the stars? Well, you engineer the space-time metric. You arrange it for spacetime to expand behind you, mimicking the inflationary conditions of the early universe. And you make spacetime collapse ahead of you, mimicking a black hole, say. Thus your spacetime bubble is pulled and pushed, driven ahead across the manifold. You are riding a propagating wave in spacetime.”
“Like surfing!”
“Yes, Mr. Meisel. Though I myself have never surfed.”
Holle thought she understood. The spacecraft would be embedded in spacetime like a toy insect in a block of glass. You didn’t transport the ship itself, but a whole chunk of the spacetime around it.
“This is the essence of the warp bubble. The transported spacetime must be large enough to keep you away from the regions of heavy curvature associated with the warp bubble itself—which would manifest, of course, like strong gravity fields. But what of travel faster than light? Einstein tells us that it is impossible to move faster than light-speed as measured against local landmarks. ” He emphasized the words heavily. “The trick is to carry those landmarks with you. The ship itself is not traveling at all relative to the spacetime bubble around it. It is the bubble itself that propagates at multiples of light speed, as desired. You are not traveling faster than light, because you are carrying the light with you . . .”
Zane was already working, paging through notes on his laptop. Holle arranged for the board’s contents to be downloaded to her handheld, and she made notes alongside Liu’s diagrams and equations. All around her the students chatted, argued, joked, and scrolled through what looked like entirely disparate bits of work. This was not like the mostly calm, mostly studious atmosphere she had got used to at the grade schools in Denver.
“The warp bubble as a method of transportation has some paradoxical properties. Because the ship is stationary relative to local landmarks, there are none of the effects we associate with special relativity: no time dilation, no Lorentz-Fitzgerald contraction. Clocks aboard the ship stay synchronized with those at the starting point, and indeed at the destination. And there will be no inertial effects.”
“What does that mean?” Holle whispered.
“You wouldn’t feel any acceleration,” Zane said. “The ship’s not moving compared to the spacetime it’s embedded in. So you don’t get squished against the back wall of your cockpit when you turn on the warp drive.”
“However, there are issues of control, for you run the risk of outrunning any signal sent forward to control your own bubble. Therefore, we think it likely that any piloted mission will have the parameters of bubble formation, propagation, dissipation and so on loaded by a remote station before launch; the crew of the starship inside the bubble will essentially be passengers.”
Joe and Mike burst into gales of laughter over some private joke.
Holle leaned over to Zane. “Is it always like this?”
“Like what?”
“Noisy. Everybody messing around.”
He shrugged. “There are no rules. They just put the material in front of you and expect you to make what you can of it.”
“And if you can’t cope with that,” said the boy next to Kelly, twisting back, “you can go back to the kiddie schools and play with the plastic bricks. There’s always
They reached their table. Zane had a laptop, and Holle dug her handheld out of her bag.
If the students had been indifferent to Holle, Liu Zheng didn’t so much as register her presence. He just carried on with what he was saying. “So how do you fly to the stars? Well, you engineer the space-time metric. You arrange it for spacetime to expand behind you, mimicking the inflationary conditions of the early universe. And you make spacetime collapse ahead of you, mimicking a black hole, say. Thus your spacetime bubble is pulled and pushed, driven ahead across the manifold. You are riding a propagating wave in spacetime.”
“Like surfing!”
“Yes, Mr. Meisel. Though I myself have never surfed.”
Holle thought she understood. The spacecraft would be embedded in spacetime like a toy insect in a block of glass. You didn’t transport the ship itself, but a whole chunk of the spacetime around it.
“This is the essence of the warp bubble. The transported spacetime must be large enough to keep you away from the regions of heavy curvature associated with the warp bubble itself—which would manifest, of course, like strong gravity fields. But what of travel faster than light? Einstein tells us that it is impossible to move faster than light-speed as measured against local landmarks. ” He emphasized the words heavily. “The trick is to carry those landmarks with you. The ship itself is not traveling at all relative to the spacetime bubble around it. It is the bubble itself that propagates at multiples of light speed, as desired. You are not traveling faster than light, because you are carrying the light with you . . .”
Zane was already working, paging through notes on his laptop. Holle arranged for the board’s contents to be downloaded to her handheld, and she made notes alongside Liu’s diagrams and equations. All around her the students chatted, argued, joked, and scrolled through what looked like entirely disparate bits of work. This was not like the mostly calm, mostly studious atmosphere she had got used to at the grade schools in Denver.
“The warp bubble as a method of transportation has some paradoxical properties. Because the ship is stationary relative to local landmarks, there are none of the effects we associate with special relativity: no time dilation, no Lorentz-Fitzgerald contraction. Clocks aboard the ship stay synchronized with those at the starting point, and indeed at the destination. And there will be no inertial effects.”
“What does that mean?” Holle whispered.
“You wouldn’t feel any acceleration,” Zane said. “The ship’s not moving compared to the spacetime it’s embedded in. So you don’t get squished against the back wall of your cockpit when you turn on the warp drive.”
“However, there are issues of control, for you run the risk of outrunning any signal sent forward to control your own bubble. Therefore, we think it likely that any piloted mission will have the parameters of bubble formation, propagation, dissipation and so on loaded by a remote station before launch; the crew of the starship inside the bubble will essentially be passengers.”
Joe and Mike burst into gales of laughter over some private joke.
Holle leaned over to Zane. “Is it always like this?”
“Like what?”
“Noisy. Everybody messing around.”
He shrugged. “There are no rules. They just put the material in front of you and expect you to make what you can of it.”
“And if you can’t cope with that,” said the boy next to Kelly, twisting back, “you can go back to the kiddie schools and play with the plastic bricks. There’s always
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