Tag: Quantum
Quantum world
Quantum world
What is Quantum Computing?
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Matrix of Dreams and Illusions merge with Real and Genuine
Matrix of Dreams and Illusions merge with Real and Genuine
What is the Matrix? matrix for starters is a movie trilogy that was released into theaters in March of 1999, with part The s 2 &3 released in May and November of 2003. 1. At every stage of your life, you will be presented with various choices. Your life boils down to the choices which you make in the course of your life. You have to make the choices very carefully, so that you don’t regret them later on in life.
2. You have to believe firmly. If you believe that something will happen, and your belief is so damn strong and intense, then that “something” cant help but happen. So believe truly and firmly in all that you think and do.
3. Know that whatever events happen in your life happen for a purpose.You just need to know the purpose and learn whatever it has to offer.
Scales Nucleon to Hubbles
QUANTUM COMPUTERS
The theory of quantum computing was first introduced by Richard Feynman. A quantum computer exploits the particle-wave duality of matter and energy to perform operations on data. Quantum properties are used to represent data and to manipulate that data. Quantum computers can solve certain problems much faster than traditional computers. The foundation of a quantum computer is the qubit, which has the encoded quantum properties of an atom. This is fundamentally different from a traditional computer, which uses bits to store data.
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If quantum computing is ever going to become the standard, we need to develop better ways to control qubits, or quantum bits. Usually, the spin of these itty-bitty quantum computer building blocks is controlled with magnetic fields. Understandably, it’s hard to get this action to take place on a chip such as one would find in a computer. Now, a team of scientists at the Kavli Institute of Nanoscience at Delft University of Technology and Eindhoven University of Technology have come up with a way to manipulate qubits with electrical fields for the first time ever.
Qubits, like standard computer bits, can be in either a “0″ or a “1″ state. In qubits, the state is determined by the direction of the electron’s spin: spinning in one direction indicates a “0″ state while spinning in the other direction denotes the “1″ state. Figuring out how to spin the electrons with electricity rather than static is an important step forward in the development of super-fast quantum computers. But the team’s incredible advances don’t stop there: they also figured out how to embed the spinning qubits into super-tiny semiconductor nanowires, another important development in the race to build the mind-blowingly fast computers of the future.
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The bit that makes quantum mechanics useful in computers just happens to be what makes it so weird. It’s also why you can have it both ways, for a little while anyhow. It’s all to do with states of being. In quantum mechanics, particles (like electrons and photons) can exist in one state or another, or in two states at the same time. That means that different things about those particles can be true at once. For example, if you’re trying to work out the flight path of a photon or particular properties of an electron, you can’t – different answers are true at the same time. At least, that is, until you look at it. That’s because when you check to see what the final answer is, you force the particle to pick a definite state and all the other states vanish, never to come back.
Regular computers put things in states too. Everything you’ve got on a computer is made out of bits, which are just zeros and ones. Nothing else – each bit is one or the other. It’s called binary code. A computer combines bits of binary to store things in memory and moves them around to do calculations. This is where the researchers hope to bring the freaky particles of quantum mechanics into play. If a computer could work in a quantum way, then a bit could be a zero and a one at the same time!
That state of being both at the same time is called superposition, and you’d only need to use a small number of particles in superposition to work with a lot of information. Only 1000 particles could store all the numbers from 1 to – well, it won’t fit on this page but it’s about 300 digits long. Manipulate your particles with a few well-placed lasers and hang on tight, because you’re quantum computing my friend.
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Faster quantum computers
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For a quantum computer to solve important problems that are intractable today, the information carried by many quantum bits, or qubits, needs to be moved around in the processor. With ion qubits, this can be accomplished by physically moving the ions. In the past, moving ions took much longer than the duration of logic operations on the ions. Now these timescales are nearly equivalent. This reduces processing overhead, making it possible to move ions and prepare them for reuse much faster than before.
NIST researchers cooled trapped ions to their lowest quantum energy state of motion and, in separate experiments, transported one and two ions across hundreds of microns in a multi-zone trap. Rapid acceleration excites the ions’ oscillatory motion, which is undesirable, but researchers controlled the deceleration well enough to return the ions to their original quantum state when they came to a stop. A research group from Mainz, Germany, reports similar results.
The secret to the speed and control is custom electronics. NIST researcher Ryan Bowler used fast FPGA (field programmable gate array) technology to program the voltage levels and durations applied to various electrodes in the ion trap. The smooth voltage supply can move the ions very fast while also keeping them from getting too excited.
With advances in precision control, researchers think ions could be transported even more quickly and yet still return to their original quantum states when they stop. Researchers must also continue to work on the many practical challenges, such as suppressing unwanted heating of the ion motion from noisy electric fields in the environment.
The research is supported by the Intelligence Advanced Research Projects Activity, National Security Agency, Office of Naval Research, and Defense Advanced Research Projects Agency
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next goal is to combine pairs of quantum bits to create a two-qubit logic gate — the basic processing unit of a quantum computer.
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Quantum computing has made significant advances in recent years, but issues of cost and complexity have kept it mainly in the realm of research. A newly proposed system from a group of Air Force and Florida Atlantic University researchers isn’t likely to make quantum computing go mainstream, but it could bring the cost of building such systems down because it could use off-the-shelf components. The system would use photons in place of electrons, but photons don’t easily interact with each other and so don’t yield up useful information easily. The traditional fix is to use a tool called an inteferometer to manipulate the photons, but that solution is relatively expensive and the tools themselves are finicky — to say nothing of the fact that it requires “cascades” of them to build a quantum computer that utilizes photons.
The proposed solution is to simply transfer the work done by the inteferometer to a hologram permanently encoded on a pane of “OptiGrate” glass. It would solve the issue of having to calibrate inteferometers, but it would also remove that option entirely as the holograms would be unchangeable on the glass. In other words, the programming would have to be hard-coded. That doesn’t mean that a quantum computer built using this method couldn’t be useful for certain tasks like quantum error correction, but it does mean that it would be difficult to scale as the panes of glass would have to be rather large to carry out anything beyond “low-dimensional quantum computations” — though stacking the holographic plates could help.
The researchers say they are “well along in understanding these devices from a theoretical perspective,” but unfortunately there aren’t any prototypes built yet. Still, the system described here would be “resistant to environmental factors” and less expensive, so hopefully a prototype won’t be too far off…
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In life, most people try to avoid entanglement, be it with unsavory characters or alarmingly large balls of twine. In the quantum world, entanglement is a necessary step for the super-fast quantum computers of the future.
According to a study published by Nature today, physicists have successfully entangled 10 billion quantum bits, otherwise known qubits. But the most significant part of the research is where the entanglement happened–in silicon–because, given that most of modern-day computing is forged in the smithy of silicon technology, this means that researchers may have an easier time incorporating quantum computers into our current gadgets.
Quantum entanglement occurs when the quantum state of one particle is linked to the quantum state of another particle, so that you can’t measure one particle without also influencing the other. With this particular study, led by John Morton at the University of Oxford, UK, the researchers aligned the spins of electrons and phosphorus nuclei–that is, the particles were entangled.
“The key to generating entanglement was to first align all the spins by using high magnetic fields and low temperatures,” said Oxford’s Stephanie Simmons, who also worked on the team…. “Once this has been achieved, the spins can be made to interact with each other using carefully timed microwave and radiofrequency pulses in order to create the entanglement, and then prove that it has been made.” [Reuters]
If the current entanglement experiment were a cooking recipe, it would go something like this: First, embed a silicon crystal with 10 billion phosphorous atoms, cool it to close to absolute zero, and then apply a sequence of radio and microwave pulses. These pulses essentially toy with the spins of the phosphorus nuclei and their electrons until the spin of each nucleus matched the spin of one of its electrons. You end up with 10 billion entangled pairs that form a two-qubit system. It’s a major breakthrough, but the researchers aren’t stopping there:
“Creating 10 billion entangled pairs in silicon with high fidelity is an important step forward for us,” said John Morton of Britain’s Oxford University, who led the team…. We now need to deal with the challenge of coupling these pairs together to build a scalable quantum computer in silicon.” [Reuters]
Spinning particles are all well and nice, but what do they have to do with computing? How does a quantum computer actually compute?
To turn this into a silicon quantum computer, the team must create a “huge 2D grid of entanglement”, in which nuclei are entangled with other phosphorus nuclei, as well as electrons, says Morton. To achieve this, electrons will be shuttled through the structure, stitching entangled states together like a thread, he says. By measuring the electron spins in a certain order, computations could be performed. [New Scientist]
Such a quantum computer would run silicon circles around conventional ones. Unlike the device sitting on your desk, quantum computers aren’t limited by the 0′s and 1′s of binary bits. In the weird world of quantum mechanics, particles can exist in more that one state at a time–they can be placed in a “superposition” of several possible states. That means that the qubits in a quantum computer could hold several different values simultaneously.
It has been shown theoretically that by running calculations in parallel, using many quantum states in superposition, a quantum computer could solve problems that would take a classical computer an infinite amount of time, for example, running Shor’s algorithm, which factors large numbers into primes and could be used, for example, to crack the most powerful encryption algorithms on the Internet. [Nature News]
In short, a quantum computer would generate a computing power the likes of which the world has never seen, capable of running–as well as cracking–evermore complex algorithms.
While impressed by the quantum leaps made by this research, scientists are already considering the next hurdles in the quantum computing story.
“It’s nice, impressive work,” says Jeremy O’Brien, a quantum-computing specialist at the University of Bristol, UK. But what is really needed, he says, is the ability to do the additional nanofabrication to put electrodes on the silicon chip to address each individual nucleus and electron pair, a technology that will be needed to get more than two spins entangled together in silicon. “That would be really impressive,” he says. [Nature News]
Even though quantum computers have a ways to go before they wind up in your living room and in your every-day gadgets, thanks to successful silicon entanglement that day is getting closer.
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http://www.nature.com/news/2011/110119/full/news.2011.29.html
http://scienceblogs.com/pontiff/2008/08/21/selfcorrecting-quantum-compute/
http://physicsworld.com/cws/article/news/2011/nov/04/silicon-carbide-shows-promise-for-quantum-computing
http://www.nature.com/nature/journal/v479/n7371/full/nature10562.html
http://advanced-level-ict.blogspot.in/2011/10/quantum-computers-at-nano-scale.html
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IF A ‘DNA COMPUTER’ DID ALREADY EXIST, THEN WE SHOULD BE ABLE TO REBUILD IT!
Everybody loves gadgets. If the DNA molecule DID function as a super-advanced computer chip, then it would use simple, everyday principles of physics to work.
There would be nothing mysterious or impossible about it.
Ultimately it would be just a little machine, waiting to be analyzed and understood.
If that were the case, then we also should be able to discover the principles of this ‘computer’ and reverse-engineer it… so we can build gadgets and gizmos!
The earliest gadgets would obviously be much, much simpler than the DNA molecule… using only the most basic aspects of the ‘technology.’ Nonetheless they would work on similar principles.
HOW WOULD WE DO IT?
The DNA molecule is built up from single atoms that arrange into a double helix.
The ultimate “proof of concept” for our seemingly radical idea would be for scientists to design a computer circuit — out of nothing more than single atoms!
Now think of a catchy name for it. How about a “quantum computer?”
Fiction?
Fact!http://go.webassistant.com/wa/upload/users/u1001065/pages/0609-848564437digGNU7QCLo/dna3.html
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Now we’re in the second quarter century of Quantum Computing. “It is widely believed that a quantum computer will not become a reality for at least another 25 years,” says Professor Jeremy O’Brien, Director of the Centre for Quantum Photonics. “However, we believe, using our new [photon quantum random walk] technique, a quantum computer could, in less than ten years, be performing calculations that are outside the capabilities of conventional computers.”>>http://hplusmagazine.com/2010/09/21/new-route-quantum-computing-photons-quantum-walk-your-future/
http://en.wikipedia.org/wiki/Quantum_computer
http://news.discovery.com/tech/nobel-physics-quantum-computers-121009.html
http://blogs.economictimes.indiatimes.com/Sigma/entry/the-india-bit-in-quantum-computing
http://www.newscientist.com/topic/quantum-world
http://phys.org/physics-news/quantum-physics/
Quantum Mechanics Latest Visions
Courtesy : Quantum Mechanics
Quantum mechanics is a realm of
weirdness: electrons being linked to each
other even though the vastness of the
universe might separate them, things being
in two places at once, and, of course,
knowledge precluding knowledge. This last
is the standard bearer of quantum oddity:
measuring the momentum of an object
precludes precise knowledge of where that
object is. But I think I have found
something that is stranger than them all.
Researchers have suggested that it might be
possible to make measurements that trick a
photon into thinking it is, in fact, a crowd of
photons.
Let’s imagine that we want to introduce a
phase shift to one single photon through a
control photon. A phase shift is basically a
time delay. In traditional optics this delay is
applied through high-intensity light beams:
a high intensity pulse can modify the
refractive index of the medium through
which it propagates. Our signal photon
traveling through that medium will see that
different refractive index and either be
delayed or sped up.
The problem is that we want to do this all
with single photons, and just one photon
does not fit the definition of high intensity.
It seems a bit hopeless, right? However, in
quantum mechanics, things are not all that
they seem. One type of measurement in
particular—called a weak measurement—
can give very strange results. For instance,
if you measure the spin of an electron using
a weak measurement, you can be
reasonably certain that you haven’t
disturbed the spin state of the electron,
but, you might get a strange value.
Electrons only take on spin values of +1/2
or -1/2, but a weak measurement could
return something like 100. So, under the
right circumstances, that single electron can
behave as if it had the spin effect of 200
electrons.
In our case, we’re using two photons. A
single control photon goes through a beam
splitter where it gets the choice of going
through the medium with a signal photon—
the one we want to phase shift—or go
through a separate channel. These paths
are then recombined at another beam
splitter, but this beam splitter isn’t quite
balanced. In a perfectly balanced splitter,
the control photon will always exit the
beam splitter in the same direction, called
the bright port. In an unbalanced beam
splitter, it’s possible for a photon to
sometimes head off in a different direction,
called the dark port.
When you calculate the possible ways that a
photon could hit a detector looking at the
dark port, one of them is that there are
simply more photons traveling through the
medium with the signal photon than on the
path outside the medium. Even better, the
closer to balanced the detector is, the rarer
the clicks on the detector for the dark port
are. So, to get a click, you need a much
larger number of photons in the medium
with the signal photon . Even if you know
you only send in one photon at a time.
In other words, we are measuring the
number of photons, but getting an answer
that is wrong by several orders of
magnitude. The truly weird thing: nature
believes us rather than reality.
If we make a weak measurement on the
number of photons in the control photon
beam, then a single photon is misreported
as several hundred. And, if everything is set
up correctly—which, in this case, means
that we only look for phase shifts on the
signal photon when the dark port detector
clicks—that lone control photon will have a
much larger effect on the refractive index of
the medium. The end result is that the
phase of the signal photon is shifted by lot
more than would normally be expected.
The catch is that this is a work of theory.
And the phase shifts, even with this
amplification factor, may be really small.
Even so, I can imagine that if you chose
your medium correctly (say an alkali metal
gas), and your wavelengths correctly (right
on the edge of an absorption feature of the
gas), then it might well be possible to
observe the amplification of the phase shift.
Like the Bell inequalities and entanglement,
we will have to wait before this can be
tested. But, unlike some quantum
phenomena, it won’t be decades from
theory to experiment.
‘Quantum machine’ takes science breakthrough title – Sunday Mercury – Weird Science
Niels Henrik David Bohr
Source – Go “en.wikipedia.org/wiki/Niels_Bohr”
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922
Born: October 7, 1885, Copenhagen
Died: November 18, 1962, Copenhagen
Education: Trinity College, Cambridge, University of Copenhagen, University of Cambridge
Awards: Nobel Prize in Physics, Copley Medal, Franklin Medal
Thus Spoke Bohr :
Prediction is very difficult, especially if it’s about the future.
Your theory is crazy, but it’s not crazy enough to be true.
Einstein, stop telling God what to do!
It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we say about Nature.
An expert is a man who has made all the mistakes which can be made, in a narrow field.
We are all agreed that your theory is crazy. The question which divides us is whether it is crazy enough to have a chance of being correct. My own feeling is that it is not crazy enough.
A physicist is just an atom’s way of looking at itself.
If quantum mechanics hasn’t profoundly shocked you, you haven’t understood it yet.
How wonderful that we have met with a paradox. Now we have some hope of making progress.
Never express yourself more clearly than you are able to think
Everything we call real is made of things that cannot be regarded as real.
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it.
There are trivial truths and the great truths. The opposite of a trivial truth is plainly false. The opposite of a great truth is also true
When it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images.
Read more at http://www.brainyquote.com/quotes/authors/n/niels_bohr.html#GpzyEAsapmYg5fqY.99
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