Quantum Computer: Limit?

Electron microscope image
of a qubit from Hans Mooij's
research group at Delft
University of Technology













Quantum computers have the potential to do certain calculations faster
than any foreseeable classical computers, but their success will depend
on preserving complex coherent quantum states. A quantum computer
makes use of the fact that a quantum mechanical system can
simultaneously exist in two states. Normally one of the two states
disappears as soon as the system comes into contact with the outside
world, and it is at this point that coherence is lost. A number of recent
discoveries have shown how to avoid that. For details on this topic, you
may read this article in Physics Today (June 1999; It's old but great)
-- Battling Decoherence: The Fault-Tolerant Quantum Computer
by Caltech Physics Professor, John Preskill.

Theoretical physicists, from the Foundation for Fundamental Research
on Matter (FOM) and Leiden University in the Netherlands, have,
claimed that quantum computers, which store information in so-called
quantum bits (or qubits), will be confronted with a fundamental limitation.

Dutch researchers Jasper van Wezel, Jeroen van den Brink and Jan
Zaanen made this claim in an article in Physical Review Letters, 17 June
2005. The claim is based on their discovery that the coherence of a qubit
-- a property essential to keeping the quantum information intact long
enough for it to be processed -- spontaneously disappears over the course
of time. The stored information vanishes along with that. They discovered
that coherence tends to disappear spontaneously, even without external
influences. The coherence in some highly promising concepts for qubits
may disappear after about a second. And the smaller the qubits, the faster
that process occurs.

This appears to pose a fundamental limitation on the development of
qubits and of working quantum computers. We still need to wait for some
experimental confirmation that can demonstrate that this phenomenon
actually occurs. For details, visit www.lorentz.leidenuniv.nl.

High-end storage from EMC

EMC unveils 2 new high-end storage arrays that give users not only
better performance but higher capacity for business critical and
transaction-intensive applications.

The Symmetrix DMX3500 and DMX4500 have more than 3 times the
storage capacity of present EMC arrays and more cache memory and
throughput for high-performance. They are not meant to replace EMC's
Symmetrix DMX800, 1000, 2000 and 3000, but to complement them
by offering systems that perform better and faster.

In addition, the new Symmetrix's will have mirrored cache, a first for
EMC storage arrays. Mirroring of cache memory provides for system
redundancy and increased availability. Increasing the size of the cache
memory is important because the system is able to store more
information quickly at hand for use by business-critical applications such
as databases. Arrays from Hitachi Data Systems and IBM such as the
TagmaStore and TotalStorage DS8000 already have mirrored cache.

The new arrays are also modular - meaning they can scale incrementally
by adding more disk drives, memory or I/O. EMC first introduced
modular arrays with the DMX Series, announced in February of 2004.

The DMX3500 has an upper capacity of 4323 T-bytes; the DMX4500
supports 576 T-bytes of data. EMC's present DMX3000 supports 172
T-bytes [1,000 terabytes or 1 petabytes is enough space to store 250
million digital music files or 2 trillion telephone transaction records].

Windows Vista - That's the Name!

Once upon a time (in fact long long ago ...) we first heard a name
'Longhorn'. Today morning that name changed forever! Today morning
Microsoft announced its next generation operating system will
henceforth be called "Windows Vista" !!

The Windows Vista Web site has also been unveiled. The first beta testing
of the system will be targeted at developers and IT professionals. It will
be available by Aug. 3. Microsoft said that the new system will have
several improvements, including better security features, more
comprehensive search capabilities and a friendlier user interface. It is
expected to be released in late 2006.

100 Mbps Cable Broadband

A competing technology for Broadband access through TV cable is brewing
up. Finnish broadband equipment maker Teleste announced today a cost
efficient technology called "Ethernet to the Home" or EttH. This can allow
100 Mbps (Megabits a second) download speeds in as early as 2006. The
speed boost would be 50 times the speed of today's cable broadband.

The method is cheaper because it utilizes the cables that are already
there. Other companies can also do the same but they need fiber
networks. EttH will create an Ethernet connection directly from the
traditional cable line to the computer. Teleste calls this system Virtual
Fibre, which runs in the cable operator's facilities and interfaces with a
cable-based Ethernet connection in the home to deliver standard
Ethernet speeds along with a cable television signal.

According to Teleste, its competitors -- Scientific Atlanta and networking
giant Cisco Systems -- won't have their own version of the technology
available until the middle of 2007.

Wireless Router with MIMO

Linksys WRT54GX XXXXXXXXX Belkin Pre-N Router

About 2 years back the wireless networking gear 802.11g was introduced.
And now the time has arrived for MIMO-enhanced routers. MIMO stands
for multiple input multiple output. Using a single channel for multiple data
streams this technology enhances both the range and the throughput
substantially over that of standard Wi-Fi gears.

The pictures above show Belkin and Linksys routers which use Airgo's
MIMO chipset and use three external antennas to transmit and receive
data.

Other advantages of MIMO are: (i) It makes devices less susceptible to
interference, (ii) It interferes less with neighboring networks than other
performance-enhancing technologies, (iii) The MIMO-enabled products
are all backward compatible with 802.11b and 802.11g devices, which
basically means that you can use them with off-the-shelf Wi-Fi gear
from other makers.

One disadvantage with MIMO-enabled devices is worth noting. It is not
based on an 802.11 standard. This means that its performance benefits
of these devices probably cannot be exploited with 802.11n gear due out
in 2006. But as long as there are talented techies around, you can afford
to hope that some solution would come out before that.

Cell Phones: .mobi Domain

The Internet Corporation for Assigned Names and Numbers (ICANN)
has approved the ".mobi" domain suffix for the exclusive use of cell phone
users accessing the Internet. This is the 17th top level domain approved
by ICANN. They have, however, indicated their doubt that .mobi websites
will be available before 2006. In any case this will certainly pave the way
for widespread use of the Web by cell phone users.

There are 1.8 billion mobile users in the world but only 12 to 14 percent
have ever used the Web from their phones. Websites using the .mobi
domain suffix for the exclusive use of cell phone users are expected to be
a stopgap solution to fill the divide between today's small-memory mobile
phones and future devices with more robust memory and processors.

A joint venture of mobile technology companies, mTLD (Mobile Top Level
Domain), expects to start issuing Internet .mobi domain names in the 1st
half of next year. It has been contracted to provide the registry service for
.mobi for the next ten years. The company, which was formed by
Microsoft, Nokia, the GSM (Global System for Mobile Communications)
Association, Vodafone Group PLC and other heavy hitters, has completed
a contract with the ICANN that formalized the creation of the .mobi
domain. This initiative is also aimed at creating opportunities for content
providers, ISVs and ASPs to extend Internet-based services to their
customers.

IBM's Dual Core Processor

In an event in Tokyo last week IBM announced its new PowerPC 970MP
chip, the dual-core version of the PowerPC 970FX. Code-named Antares,
the 970MP yields more than double the performance of its predecessor.
Its target is customers are those who require 64-bit symmetric
multiprocessing (SMP) in a small, entry-level embedded system ranging
from 1.4 to 2.5 GHz.

Each of the two 64-bit PowerPC 970MP sockets, or cores, has its own
dedicated 1 MB L2 cache, making it much more powerful than the 970FX.
The PowerPC 970MP is designed to conserve energy despite its higher
performance levels. The frequency and voltage of both sockets can also
scale downward to reduce the power during periods of reduced workload.
Each socket can be placed in a state called "doze", which saves power
while the other core continues running. One of the cores can also be shut
down during periods of less traffic.

The dual-core technology provides tremendous performance increases
while only consuming the power of a single-socket processor. Dual core
chips have been popular in 2005 since AMD and Intel began trotting out
their offerings for PCs, servers, workstations and other devices.

IBM did not comment if Apple, which uses the 970FX in its Macintosh
computers running G5 chips, has been testing the PowerPC 970MP after
a recent pledge to work with Intel over IBM.

Computer Implant

Bill Gates commented in a Microsoft seminar in Singapore that
technological advances will one day allow computers to be implanted in
the human body and could help the blind see and the deaf hear.

He noted that cochlear implants and other medical implants were
already being used to treat hearing problems and some conditions that
cause constant pain, and were changing some people's lives dramatically.
Cochlear implants, which employ digital pulses that the brain interprets
as sound, can help profoundly deaf people hear. Advances were also being
made on implants that can help fix eyesight problems.

He cited author Ray Kurzweil, whom he called the best at predicting the
future of artificial intelligence, as believing that such computer-human
links would become mainstream -- though probably not for several
generations. Gates also predicted that the keyboard won't be replaced by
voice recognition software, and that the pen will make a comeback --
although without ink. The three would form the basic ways people will
interact with their computers in the future. He said when computer pen
technology -- scratching words onto a screen that a computer tries to read
-- gets more sophisticated it will do things like let people draw musical
notes and chemical signs, as well as recognize handwriting.

Meshing people directly with computers has been a science fiction subject
for years, from downloading memories onto computer chips to
replacement robotic limbs controlled by brain waves. The fantasy is now
coming closer to reality as advances in technology mean computers are
learning to interact with human characteristics such as voices, touch --
even smell.