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| '''Adiabatic quantum computation''' ('''AQC''') relies on the [[adiabatic theorem]] to do calculations<ref name="Farhi2000">
| | Real value stocks can be a fine investment, offering the investor both generous dividends and rising stock prices in the future. Some stock tips that look like bargains turn out to be losers, not value stocks.<br><br>I sure many of us have heard about this statement. It apply for stock trading and investment as well. Many of us [http://news.goldgrey.org/precious-metals/ gold eagles] get into the stock market wishing to make BIG BIG money at the FASTEST and SHORTEST time. That's a gambler mindset. Imagine this, you heard your friends, or your relatives talking about a specific stock counter, how fast it grows and how it make money. I am sure you will start to feel a bit greedy and like to involve in the game. Then, you follow their suggestion, call up your broker and place an order. Good, the stock started to grow, but suddenly it crashed. You ended up holding on to the stock with huge paper loss.<br><br>trading stocks is tricky if not extremely risky. However it can be very rewarding if you know what you are doing and be able to find trouble before it finds you. Some solid tips are to trade during transition times of banks opening and closing, around 3pm eastern to 7pm eastern. This will create a prime spot to trade amongst the US and Asian markets in a sideways trend. Don't expect a lot to happen here but a good chunk of change can be made and it does move up and down, just when it is in a sideways trend it doesn't move all that much, however sometimes it does. So prepare to benefit from that, or exit if need be.<br><br>Investment in stock market is not as risky a venture as laymen talk of it, provided, you are careful and do not lose your wits to greed. But before knowing what to do and what not to in the stock exchange, first know what stocks actually are. investing in stocks means that you are investing in a company, which invests the money in its business. As it earns profit from the business, it gives your share of profit to you. So, you only invest money in the business and the skills of the company and it works for you to earn profit for you.<br><br>The recovery is at a point now where sales and revenues must grow to achieve continued improvement. Companies can no longer cut expenses to make money. To grow they need to hire. The business just needs to be there.<br><br>The system uses a stop loss strategy. You will get rid of a stock that is not profitable so it will save you money. This is very important especially for beginners to know. |
| {{cite arXiv |author= [[Edward Farhi]], [[Jeffrey Goldstone]], [[Sam Gutmann]], [[Michael Sipser]] |eprint=quant-ph/0001106 |title=Quantum Computation by Adiabatic Evolution |year=2000 |version=v1 |accessdate=2007-11-26 }}</ref> and is closely related to [[quantum annealing]].<ref>T. Kadowaki and H. Nishimori, "Quantum annealing in the transverse Ising model" [http://pre.aps.org/abstract/PRE/v58/i5/p5355_1 Phys. Rev. E 58, 5355 (1998)]</ref><ref>A. B. Finilla, M. A. Gomez, C. Sebenik and D. J. Doll, "Quantum annealing: A new method for minimizing multidimensional functions" [http://www.sciencedirect.com/science/article/pii/0009261494001170 Chem. Phys. Lett. 219, 343 (1994)]</ref><ref>G. E. Santoro and E. Tosatti, "Optimization using quantum mechanics: quantum annealing through adiabatic evolution" [http://iopscience.iop.org/0305-4470/39/36/R01 J. Phys. A 39, R393 (2006)]</ref><ref>A. Das and B. K. Chakrabarti, "Colloquium: Quantum annealing and analog quantum computation" [http://rmp.aps.org/abstract/RMP/v80/i3/p1061_1 Rev. Mod. Phys. 80, 1061 (2008)]</ref> First, a complex [[Hamiltonian (quantum mechanics)|Hamiltonian]] is found whose ground state describes the solution to the problem of interest. Next, a system with a simple Hamiltonian is prepared and initialized to the ground state. Finally, the simple Hamiltonian is adiabatically evolved to the complex Hamiltonian. By the adiabatic theorem, the system remains in the ground state, so at the end the state of the system describes the solution to the problem.
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| AQC is a possible method to get around the problem of [[Quantum dissipation|energy relaxation]]. Since the quantum system is in the ground state, interference with the outside world cannot make it move to a lower state. If the energy of the outside world (that is, the "temperature of the bath") is kept lower than the energy gap between the ground state and the next higher energy state, the system has a proportionally lower probability of going to a higher energy state. Thus the system can stay in a single system eigenstate as long as needed.
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| Universality results in the adiabatic model are tied to quantum complexity and [[QMA]]-hard problems. The k-local Hamiltonian is QMA-complete for k ≥ 2.<ref>{{Cite journal | last1=Kempe | first1=Julia | last2=Kitaev | first2=Alexei | last3=Regev | first3=Oded | title=The Complexity of the Local Hamiltonian Problem | publisher=[[Society for Industrial and Applied Mathematics]] | location=Philadelphia | year=2006 | journal=SIAM Journal on Computing | issn=1095-7111 | volume=35 | issue=5 | pages=1070–1097 | arxiv=quant-ph/0406180v2 | doi=10.1137/S0097539704445226}}.</ref> QMA-hardness results are known for physically realistic [[lattice models]] of [[qubits]] such as <ref>{{Cite journal | last1=Biamonte | first1=Jacob | last2=Love | first2=Peter | title=Realizable Hamiltonians for Universal Adiabatic Quantum Computers | publisher=[[Physical Review]] | year=2008 | journal= Phys. Rev. A | volume=78 | issue=1 | pages=012352 | arxiv=arXiv:0704.1287 | doi=10.1103/PhysRevA.78.012352}}.</ref>
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| <math>
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| H = \sum_{i}h_i Z_i + \sum_{i<j}J^{ij}Z_iZ_i + \sum_{i<j}K^{ij}X_iX_i
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| </math>
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| where <math>Z, X</math> represent the [[Pauli matrices]] <math>\sigma_z, \sigma_x</math>. Such models are used for universal adiabatic quantum computation. The Hamiltonians for the QMA-complete problem can also be restricted to act on a two dimensional grid of [[qubits]]<ref>{{Cite arXiv
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| | last = Oliveira
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| | first = Roberto
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| | coauthors = Barbara M Terhal
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| | title = The complexity of quantum spin systems on a two-dimensional square lattice
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| | volume = 8
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| | number = 10
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| | pages = 0900-0924
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| | journal = Quant. Inf, Comp.
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| | eprint = quant-ph/0504050
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| | class=quant-ph
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| | date = 2008
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| }}</ref> or a line of quantum particles with 12 states per particle.<ref>{{Cite journal
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| | doi = 10.1007/s00220-008-0710-3
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| | volume = 287
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| | issue = 1
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| | pages = 41–65
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| | last = Aharonov
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| | first = Dorit
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| | coauthors = Daniel Gottesman, Sandy Irani, Julia Kempe
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| | title = The Power of Quantum Systems on a Line
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| | journal = Communications in Mathematical Physics
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| | date = 2009-04-01
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| }}</ref> and if such models were found to be physically realisable, they too could be used to form the building blocks of a universal adiabatic quantum computer.
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| In practice, there are problems during a computation. As the Hamiltonian is gradually changed, the interesting parts (quantum behaviour as opposed to classical) occur when multiple [[qubit]]s are close to a tipping point. It is exactly at this point when the ground state (one set of qubit orientations) gets very close to a first energy state (a different arrangement of orientations). Adding a slight amount of energy (from the external bath, or as a result of slowly changing the Hamiltonian) could take the system out of the ground state, and ruin the calculation. Trying to perform the calculation more quickly increases the external energy; scaling the number of qubits makes the energy gap at the tipping points smaller.
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| For a theoretical study of the performance of an adiabatic optimization processor see.<ref>Kamran Karimi, Neil .G. Dickson, Firas Hamze, et al., Investigating the Performance of an Adiabatic Quantum Optimization Processor, Quantum Information Processing, Volume 11, Number 1, 2012, http://arxiv.org/abs/1006.4147</ref>
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| ==D-Wave quantum processors==
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| The [[D-Wave One]] is an adiabatic quantum annealer made by a Canadian company [[D-Wave Systems]]. In 2011, [[Lockheed-Martin]] purchased one for about US$10 million; in May 2013, [[Google]] purchased a [[D-Wave Two]] with 512 qubits.<ref>{{cite web |url=http://www.nature.com/news/computing-the-quantum-company-1.13212 |title=Computing: The quantum company |last=Jones |first=Nicola |date=19 June 2013 |website=[[Nature (journal)|Nature]] |pages=286–288 |publisher=Nature Publishing Group |accessdate=2 January 2014}}</ref> As of now, the question of whether the D-Wave processors offer a speedup over a classical processor is still unanswered. Tests performed by researchers at [[University of Southern California|USC]], [[ETH Zurich]], and [[Google]] show that as of now, there is no evidence of a quantum advantage.<ref>{{cite journal|last=Boixo et. al.|title=Quantum annealing with more than one hundred qubits|date=April 2013|url=http://arxiv.org/abs/1304.4595}}</ref><ref>{{cite journal|last=Ronnow et. al.|title=Defining and detecting quantum speedup|date=January 2014|url=http://arxiv.org/abs/1401.2910}}</ref> | |
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| ==Notes==
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| {{Reflist}}
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| {{Quantum computing}}
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| [[Category:Quantum mechanics]]
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| [[Category:Physics theorems]]
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Real value stocks can be a fine investment, offering the investor both generous dividends and rising stock prices in the future. Some stock tips that look like bargains turn out to be losers, not value stocks.
I sure many of us have heard about this statement. It apply for stock trading and investment as well. Many of us gold eagles get into the stock market wishing to make BIG BIG money at the FASTEST and SHORTEST time. That's a gambler mindset. Imagine this, you heard your friends, or your relatives talking about a specific stock counter, how fast it grows and how it make money. I am sure you will start to feel a bit greedy and like to involve in the game. Then, you follow their suggestion, call up your broker and place an order. Good, the stock started to grow, but suddenly it crashed. You ended up holding on to the stock with huge paper loss.
trading stocks is tricky if not extremely risky. However it can be very rewarding if you know what you are doing and be able to find trouble before it finds you. Some solid tips are to trade during transition times of banks opening and closing, around 3pm eastern to 7pm eastern. This will create a prime spot to trade amongst the US and Asian markets in a sideways trend. Don't expect a lot to happen here but a good chunk of change can be made and it does move up and down, just when it is in a sideways trend it doesn't move all that much, however sometimes it does. So prepare to benefit from that, or exit if need be.
Investment in stock market is not as risky a venture as laymen talk of it, provided, you are careful and do not lose your wits to greed. But before knowing what to do and what not to in the stock exchange, first know what stocks actually are. investing in stocks means that you are investing in a company, which invests the money in its business. As it earns profit from the business, it gives your share of profit to you. So, you only invest money in the business and the skills of the company and it works for you to earn profit for you.
The recovery is at a point now where sales and revenues must grow to achieve continued improvement. Companies can no longer cut expenses to make money. To grow they need to hire. The business just needs to be there.
The system uses a stop loss strategy. You will get rid of a stock that is not profitable so it will save you money. This is very important especially for beginners to know.