CHAPTER 5

Peter had known Sarkar Muhammed since they’d both been teenagers. They’d lived on the same street, although Sarkar had gone to a private school. They had perhaps seemed unlikely prospects for friendship. Sarkar was heavily involved in athletics. Peter was on his school’s yearbook and newspaper staffs. Sarkar was devoutly Muslim. Peter wasn’t devoutly anything. But they’d hit it off shortly after Sarkar’s family moved into the neighborhood. Their senses of humor were similar, they both liked to read Agatha Christie, and they were both experts at Star Trek trivia. Also, of course, Peter didn’t drink, and that made Sarkar happy. Although Sarkar would eat in licensed restaurants, he avoided whenever possible sitting at a table with someone who was imbibing alcohol.

Sarkar had gone to the University of Waterloo to study computer science. Peter had studied biomedical engineering at U of T. They’d kept in touch all through university, swapping E-mail letters over the Internet. After a brief stint in Vancouver, Sarkar had ended up back in Toronto, running his own high-tech startup firm doing expert-systems design. Although Sarkar was married and had three children, Peter and he often dined out together, just the two of them.

Incongruously, dinner was always at Sonny Gotlieb’s, a deli at Bathurst and Lawrence, in the heart of Toronto’s Jewish district. Peter couldn’t stand Pakistani cuisine, despite Sarkar’s valiant efforts to broaden his palate, and Sarkar had to eat where he could get food that adhered to Islamic dietary laws — something which most kosher fare managed to do admirably. And so the two of them sat in their usual booth, surrounded by zaydes and bubbehs chatting away in Yiddish, Hebrew, and Russian.

After they had ordered, Sarkar asked Peter what was new. “Not much,” said Peter, his tone guarded. “What about you?”

Sarkar spoke for a couple of minutes about a contract his company had received to do expert-systems for the New Democratic Party of Ontario. They’d only been in power once, in the early 1990s, but were always hoping to make a comeback. Before Canadian socialist governments disappeared completely from living memory, they wanted to capture the knowledge of party members who had actually been in power back then.

Peter half listened to this. Ordinarily, he found Sarkar’s work fascinating, but tonight his mind was a million kilometers away. The waiter returned with a pitcher of Diet Coke for them, and a basket of assorted bagels.

Peter wanted to tell Sarkar about what had happened with Cathy. He opened his mouth a couple of times to say something, but always lost his nerve before the words got out. What would Sarkar think of him if he knew? What would he think of Cathy? He thought at first that he wasn’t telling Sarkar because of his religion; Sarkar’s family was prominent in the Toronto Muslim community and Peter knew that they still practiced arranged marriages. But that wasn’t it. He simply couldn’t bring himself to speak aloud to anyone — anyone — about what had happened.

Although he wasn’t really hungry, Peter took a poppy-seed bagel from the basket and spread a little jam on it.

“How is Catherine?” Sarkar asked, helping himself to a rye bagel.

Peter took advantage of having his mouth full to buy a few seconds to think. Finally, he said, “Fine. She’s fine.”

Sarkar nodded, accepting that.

A little later Sarkar asked, “How’s the second weekend in September sound for our trip up north?”

For six years now, Peter and Sarkar had been going away for a weekend of camping in the Kawarthas. “I — I’ll have to get back to you about that,” said Peter.

Sarkar helped himself to another bagel. “Okay.”

Peter loved those camping weekends. He wasn’t much of an outdoorsperson, but he enjoyed seeing the stars. He’d never really agreed to an annual excursion, but with Sarkar anything done twice instantly became an inviolable tradition.

Getting away would be good, thought Peter. Very good.

But—

He couldn’t go.

Not this year. Maybe not ever.

He couldn’t leave Cathy alone.

He couldn’t, because he couldn’t be sure that she would in fact be alone.

Dammit. God damn it.

“I’ll have to get back to you,” Peter said again.

Sarkar smiled. “You said that.”

Peter realized the whole evening would be a disaster if he didn’t get his mind on something else. “How’s that new brain scanner my company built for you working out?” Peter asked.

“Great. It’s going to really simplify our neural-net studies. Wonderful machine.”

“Glad to hear it,” said Peter. “I’ve been working on refining it, trying to get a higher level of resolution.”

“The current resolution is more than adequate for the kind of work I do,” said Sarkar. “Why would you want more?”

“Remember when I was doing my practicum at U of T? I told you about that transplant donor who woke up on the operating table?”

“Oh, yes.” Sarkar shivered. “You know my religion is suspicious of transplants. We feel the body should be returned to the Earth whole. Stories like that make me believe that even more.”

“Well, I still have nightmares about it. But I think I’m finally going to be able to put that demon to rest.”

“Oh?”

“That scanner we developed for your work was just a first-stage unit. I really wanted to develop a — a superEEG, if you will, that can detect any electrical activity at all in the brain.”

“Ah,” said Sarkar, his eyebrows lifting, “so you can tell when someone is really dead?”

“Precisely.”

The server arrived with their main courses. Peter had a stack of Montreal smoked meat and rye bread, accompanied by a little carousel rack of various mustards and a side order of latkes — what Sarkar referred to as Peter’s heart-attack kit. Sarkar had gefilte fish.

“That’s right,” said Peter. “I’ve been poking at this for years now, but I’ve finally had the breakthrough I needed. Signal-to-noise-ratio problems were killing me, but while scanning the net I found some algorithms created for radio astronomy that finally let me solve the problem. I’ve now got a working prototype superEEG.”

Sarkar put down his fork. “So you can see the last neural gasp, so to speak?”

“Exactly. You know how a standard EEG works: each of the brain’s billions of neurons is constantly receiving excitatory synaptic input, inhibitory input, or a combination of the two, right? The result is a constantly fluctuating membrane potential for each neuron. EEGs measure that potential.”

Sarkar nodded.

“But in a standard EEC, the sensor wires are much bigger in diameter than individual neurons. So, rather than measuring the membrane potential of any one neuron, they measure the combined potential for all the neurons in the part of the brain beneath the wire.”

“Right,” said Sarkar.

“Well, that coarseness is the source of the problem. If only one neuron, or a few dozen or even a few hundred are reacting to synaptic input, the voltage will be orders of magnitude below what an EEC can read. Even though the EEC shows a flat line, brain activity — and therefore life — may still be continuing.”

“A crisp problem,” said Sarkar. “Crisp” was his favorite word; he used it to mean anything from well-defined to delicate to appealing to complex. “So you say you’ve found the solution?”

“Yes,” said Peter. “Instead of the small number of wires used by a standard EEG, my superEEG uses over one billion nanotech sensors. Each sensor is as tiny as an individual neuron. The sensors blanket the skull, like a bathing cap. Unlike a standard EEG, which picks up the combined signal of all the neurons in a given area, these sensors are highly directional and pick up only the membrane potential from neurons directly beneath them.” Peter held up a hand. “Of course, a straight line drawn through the brain will intersect thousands of neurons, but by cross-referencing the signals from all the sensors, I can isolate the individual electrical activity of each and every neuron in the entire brain.”

Sarkar ate another fish ball. “I see why you were having signal-to-noise problems.”

“Exactly. But I’ve solved that now. With this equipment, I should be able to detect any electrical activity at all in the brain, even if it’s just one lone neuron firing.”

Sarkar looked impressed. “Have you tried it yet?”

Peter sighed. “On animals, yes. A few large dogs — I haven’t been able to make the scanning equipment small enough to use on a rat or rabbit yet.”

“So does this superEEG actually do what you want? Does it show the exact, crisp moment of actual death — the ultimate cessation of brain electrical activity?”

Peter sighed. “I don’t know. I’ve got gigabytes of recordings of Labrador retriever brain waves now, but I can’t get a permit to put any of them to sleep.” He spread some more mustard on his meat. “The only way to test it properly will be with a dying human being.”

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