More than 80 percent of the matter in
the universe consists of an unknown substance that cannot be seen
through any telescope nor detected in any lab. This invisible stuff
interacts with normal matter only through gravity, which is how
astronomers first inferred its existence. More recently, computer models
have demonstrated that dark matter is actually crucial to the visible
realm. Without it, galaxies never would have pulled together. There
would be no stars. There would be no people.
Although astronomers still do not know exactly what dark
matter is, in 2012 they learned a lot more about how it works. One team
traced the way it spreads its tentacles throughout the cosmos. And
another found hints that dark matter may not always be invisible after
all.
Last January, Ludovic van Waerbeke of the University of British Columbia and Catherine Heymans of the University of Edinburgh announced that they had mapped a web of dark matter
more than 1 billion light-years across. "That's the largest map ever
made of dark matter," Van Waerbeke says. Although the dark stuff cannot
be observed directly, its gravity bends light from any galaxies shining
through it. Measuring the amount of bending reveals how much dark matter
is present.
Van Waerbeke and Heymans collected data for more than five
years using the Canada-France-Hawaii Telescope atop Mauna Kea in
Hawaii. They then analyzed light from 10 million galaxies, noting
exactly where concentrations of dark matter distorted the galaxies'
appearance. The resulting map shows gigantic clumps and strands of dark
matter separated by enormous voids, with all the visible galaxies in the
universe embedded in the dark web. The structure closely resembles what
computer models predicted, but Van Waerbeke notes that the new map
covers less than 0.4 percent of the sky. "It doesn't mean we won't find
anything weird when we go to much larger coverage," he says.
Last summer, two astrophysicists from the University of
California, Irvine, took another step toward making sense of the dark
universe. They detected a stream of gamma rays
from the center of our galaxy, the Milky Way, and suggested the
radiation might be linked to dark matter. According to some theories,
dark matter consists of particles called WIMPs (weakly interacting
massive particles) that could destroy each other on contact. If so,
whenever dark particles collide, they would release a burst of
high-energy radiation.
Kevork Abazajian and Manoj Kaplinghat found the gamma-ray
signal in data collected by NASA’s Fermi Gamma-Ray Space Telescope. They
tried to account for it from known objects, but dark matter was also
consistent with the observations. The case is far from closed, though.
The center of the Milky Way is a violent place, and the sheer intensity
of radiation there leaves any interpretation open to question. Abazajian
and Kaplinghat continue to mine data from the Fermi telescope,
attempting to confirm their interpretation. If they are right, they are
seeing levels of reality that go even deeper than the mind-boggling
discoveries at the Large Hadron Collider.
"Dark matter is telling us there are fundamental things
that we don't understand about physics," says Van Waerbeke. "Maybe we
are at the beginning of a complete revolution."
Debut of the Mind-Controlled Robots
Using
a brain implant, a paralyzed stroke victim directed a robotic arm to
accomplish basic tasks. People who cannot control their limbs may soon
regain movement and independence.
John Donoghue, the director of the Institute for Brain Science at Brown University,
could not contain his excitement. For years he had been working on a
revolutionary method to pick up brain signals from paralyzed patients
and translate them into commands to move mechanical limbs. If all went
well in this experiment, Cathy Hutchinson, a 58-year-old woman who lost
the use of her limbs in a stroke, would control a robotic arm and hand
and use them to lift a bottle of coffee to her mouth—just by thinking.
"Guys," Donoghue told his collaborators, "buy the most expensive camera
we can afford and shoot this in high-definition. This is a historic
moment."
And so it was. Hutchinson sipped coffee from a bottle, the
first time she had served herself in 14 years and the first time a
person had ever guided a robotic limb with her thoughts. The achievement
was reported in a May 2012 Nature article.
In a sense Donoghue, 63, has been building up to this
moment all his life. As a child, he suffered from Leggs-Calvé-Perthes
disease, which prevented him from walking for two years. In his first
job after college, he worked at the Walter E. Fernald State School, an
institution for the mentally handicapped. "I was looking at brains in
the lab and then looking out the window at people who had brain diseases
that completely took away their humanity, their ability to interact,"
he says. "I've been trying to understand what the brain is doing because
to me the brain is the organ of our humanity. It gives us our mental
life, and that makes us what we are." DISCOVER senior editor Kevin
Berger spoke with Donoghue in his Brown University office.
You have found a way to help paralyzed people by
converting brain signals into computer code to maneuver a robotic arm.
How does that work?
Neurons in the brain create electric signals. When the
neurons are sufficiently tickled by inputs, they fire electrical
impulses called spikes. We have a simple tool to record those spikes,
the microelectrode, which has been around since the 1930s. EEG
[electroencephalography] electrodes record the neurons' activity from
outside the head or on top of the cortex, but the resolution is blurry.
It’s sort of like listening from the Goodyear blimp to a crowd in the
sports stadium. You need to drop the microphone right next to people's
mouths to really hear them.
So you created that neural microphone—a silicon
chip with 100 electrodes implanted in the brain—and connected it with
wires to a computer. Then what do you do?
Once I have the microelectrode array in your motor cortex,
the brain's command center for movement, you watch a cursor on a video
moving left and right. I then say, "Imagine you’re doing that by moving
your hand on a mouse." As you imagine doing this, and the cursor moves
to the right, I record the number of spikes, and it's five. And when the
cursor moves to the left, it’s two. So now I have a coding model. Five
means right, two means left.
You can tell what I want to do by recording a single neuron? But we have 100 billion neurons in our brain!
That's what's so remarkable. The brain operates over broad
networks. There's a tendency to think you've got one neuron that’s
saying "left." But if that one cell dies, it doesn’t make any
difference, because the message is distributed over many neurons. Of the
many million neurons in the motor cortex, most of them have some kind
of information about leftness. Now, the code for a single neuron is not
so simple. Sometimes imagining left might produce two spikes, sometimes
four. It's variable. So we average a set of neurons together. With [my
patient] Cathy, we were using a few dozen neurons, and the computer
decoded the likelihood that they were signaling "go left" or "go right."
How does that code then tell the robotic arm what to do?
The signal comes out of the computer, and it's converted
into electronic commands that the robot arm understands as: move a
little bit forward, back, up, down, go left, go right, or open or close
the hand.
That process sounds almost magical, controlling a
device with your thoughts. But the process wasn't instant or intuitive;
you needed the prerecorded sessions with Cathy Hutchinson to establish a
map of her brain signals for the computer, right?
Right. We play all the data through the computer, and it
gives the commands. Virtually 100 percent of people who hear Cathy's
story for the first time think that she’s learning how to control a
cursor or robotic arm. In reality, she doesn't learn anything. She tries
to control the arm by imagining she's controlling it. And we use the
neural data from her brain and the map of her brain signals we've
generated to understand what she's trying to do and make that happen.
Does that mean we are safe from thought police hacking into our brains to detect whether we're about to commit a crime?
I don't think we can go there. But what might happen is
that we could address schizophrenia, depression, or other psychiatric
diseases. I could imagine that with an electrode array in the right
location in the brain, we might learn to understand the differences in
neuronal spiking between normal and aberrant brains. It may be that a
disease forms aberrant patterns, and those patterns lead to the
psychosis. This is a little bit sci-fi, but it's in the realm of things
that could be done. Imagine you could deliver medication to the site in
the brain when it's upset. With hair-thin electrodes, it is now possible
to put a pump on the side of them and deliver drugs to the site when
there is aberrant activity, quiet it down.
You have said that your system could eventually be
wireless, with implants transmitting signals to a wearable device that
would steer the robotic limbs. Could paralyzed people then walk again,
using an exoskeleton frame?
Technically, yes, but we don't know a lot yet about the
source of leg signals. And the problem of walking is much harder. You
have to coordinate both limbs and balance. Another complication is the
cosmetic factor. Christopher Reeve once said, "I don’t want to look like
a robot." That goes for nearly everybody who is disabled. Also, today's
wheelchairs are pretty good. So our focus is the arms. If you can't
move your arms, it is extraordinarily debilitating. We want to give
paralyzed people back something that is extremely liberating.
Impatient Futurist: Your Domestic Robot Servant Has Finally Arrived (in a Fashion)
Like many people with limited social skills,
I’ve always wanted a robot. And I’ve never been the least put off by the
strict movie rule that having a robot can only result in its owner
being pushed down the stairs, sucked into the vacuum of outer space, or
enslaved with what’s left of humanity. I’m well aware that movie rules
are hardly ever wrong, but it hasn’t been fear of betrayal that’s kept
me from having a robot helper. It’s been the lack of their existence, in
spite of a century of big talk. And this has left me not only without
the sort of non–emotion-experiencing companion who could really
understand me but also with a lot more laundry, cooking, dirty dishes,
and child care than a technophilic citizen of the 21st century should
have to put up with.
Useful home robots have always been about 20
years in the future, according to experts—a discouraging estimate, since
the same experts assure me every other exciting technology under
development is only 5 years away. Yes, I know, you can drive over to
Walmart and pick up a carpet-vacuuming “robot” to keep your lawn-mowing
“robot” company. While you’re there, why don’t you also grab a “house”
in the camping department? I’ve got no interest in keeping company with
hundreds of dumb, whirring little things. Scampering scrubbers and
pot-stirrers are way too small and stupid to push me down the stairs
when I’m not looking.
I’m hardly more impressed with the current
small crop of machines that fall into the category of sticking a laptop
on a wheeled dress mannequin and calling it a robot. The best you’re
going to do there is Luna, a human-size “robot” that will soon be widely available from a company called RoboDynamics
in Santa Monica, California, for $3,000—incredibly cheap for a
humanoid, but incredibly expensive for a device that can’t do much more
than try not to bump into furniture and senior citizens as it
desultorily wheels itself around your home, toting a tray of drinks
you’ve carefully placed on its precarious, pipe-like “arms.” Don’t count
on much more than that from Ava, a forthcoming armless “robot” from iRobot (the Roomba folks) that replaces the laptop head with an iPad head. Please.
No, I’m holding out for something more along the lines of Personal Robot 2, or PR2 to its friends. Now there’s a robot I’d be proud to be enslaved by. Sold by Willow Garage
in Menlo Park, California, 2 doesn’t merely slink around your home, it
actually does useful stuff. Get this: PR2 can fold laundry, walk and
pick up after dogs, and cook a complete breakfast of Weisswurst
Frühstück. That’s probably a lot more than you do around the house,
assuming you’re not one of those Bavarian superspouses who try to make
the rest of us look bad.
And PR2 has viable competition for my enslavement: HERB
(a.k.a. Home Exploring Robotic Butler, in keeping with the
intergalactic law requiring all robot names to be colorless acronyms),
developed by the Personal Robotics Lab
at Carnegie Mellon University. HERB can, among many other things, fetch
beer, which is critical—any robot I buy that can’t do as much is going
straight back to Amazon. What’s more, HERB can pick up and carry around
mugs of coffee and later bring the empty mugs to the sink, and has been
enlisted at parties to do this all day long. This really impresses me,
because it’s what I do all day long, too, and it’s taken me quite a
while to get good at it.
So why don’t i consider myself to be
living in the age of home robots? I hate to go negative on my future
best friends/masters, but I feel obligated to point out their
shortcomings. PR2 can do cool things, but only under tightly controlled
conditions, and with uneven results. For example, the only laundry it
can fold is a towel, and it takes it six minutes to fold a single one
(bright sideishly, that’s down from 25 minutes in earlier versions).
Also PR2 costs $400,000. That would be a big drawback for me, too, if it
weren’t for the generous expense budget I get as a columnist. HERB is
similarly limited—it dropped eight mugs during the aforementioned
party—and would probably be at least as expensive if it were buyable.
Which it isn’t.
Firoz claims that at the mahurat of Power, Ajay saw his intended
leading lady and recoiled. "Anil, Ajay and Sanju were on stage when the
lady arrived. Ajay was very upset. After the mahurat, Sanju whom I am
very close to warned me that Ajay was unhappy. When I asked Santoshi
about Ajay's approval of the girl he laughed off my misgivings. A week
later Ajay said he was no more interested in doing Power. The project fell through. Logically and ethically, Santoshi should have returned my money for Power and proceeded to make Baba Jaan
with Abhishek. Instead Santoshi went to Abhishek with another project
for another producer. Abhishek being from a cultured family refused to
work on another project with Santoshi. Some days later Santoshi landed
up at my home and created a ruckus, screaming and ranting at me. I
requested him to calm down. Two days later he went to Filmistan to meet
Ajay and Sanju while they were shooting for Rascals. Over there
Santoshi created this entire drama about me threatening him. That drama
has not ended for four years. According to Santoshi I've no work except
to threaten him." 
On July 11, Firoz rang up Santoshi asking for a meeting. "Again Santoshi
evaded a meeting. I told him I am not a corporate house that can write
off crores as production deficit. Santoshi even told me that the money I
had given to Mr. Bachchan was not to be part of Santoshi's liabilities.
I told him to return my money or I'll ask my legal team to get into
action. He suggested we meet after 4-5 days. I insisted we meet and
offered to drive down to his home which is not even 5 minutes' distance
from my home. I got into my car and drove to Santoshi's home. Before I
could reach he called to say he wasn't home. I asked him what his
intention were and why was he cheating me. I insisted on waiting below
his home. However he persuaded me to return and I did. The next thing
that happened is, on July 22-11 days after my attempts to meet him-he
complained to the police that I had threatened him. He's telling
everyone I threatened to kill him and his family. Yeh sab kya hai? Could he please show any phone call or letter that I had threatened him?" 
Tens of thousands attended rallies in the run up to the elections
